Strength of masonry blocks made with recycled concrete aggregates

NASA Astrophysics Data System (ADS)

Matar, Pierre; Dalati, Rouba El

The idea of recycling concrete of demolished buildings aims at preserving the environment. Indeed, the reuse of concrete as aggregate in new concrete mixes helped to reduce the expenses related to construction and demolition (C&D) waste management and, especially, to protect the environment by reducing the development rate of new quarries. This paper presents the results of an experimental study conducted on masonry blocks containing aggregates resulting from concrete recycling. The purpose of this study is to investigate the effect of recycled aggregates on compressive strength of concrete blocks. Tests were performed on series of concrete blocks: five series each made of different proportions of recycled aggregates, and one series of reference blocks exclusively composed of natural aggregates. Tests showed that using recycled aggregates with addition of cement allows the production of concrete blocks with compressive strengths comparable to those obtained on concrete blocks made exclusively of natural aggregates.

19 CFR 10.91 - Prototypes used exclusively for product development and testing.

Code of Federal Regulations, 2014 CFR

2014-04-01

... prototypes or any part(s) of the prototypes may be sold as scrap, waste, or for recycling, as prescribed in..., or for recycling. This includes a prototype or any part thereof that is incorporated into another product, as scrap, waste, or recycled material. If sold as scrap, waste, or for recycling, applicable duty...

19 CFR 10.91 - Prototypes used exclusively for product development and testing.

Code of Federal Regulations, 2011 CFR

2011-04-01

... prototypes or any part(s) of the prototypes may be sold as scrap, waste, or for recycling, as prescribed in..., or for recycling. This includes a prototype or any part thereof that is incorporated into another product, as scrap, waste, or recycled material. If sold as scrap, waste, or for recycling, applicable duty...

19 CFR 10.91 - Prototypes used exclusively for product development and testing.

Code of Federal Regulations, 2010 CFR

2010-04-01

... prototypes or any part(s) of the prototypes may be sold as scrap, waste, or for recycling, as prescribed in..., or for recycling. This includes a prototype or any part thereof that is incorporated into another product, as scrap, waste, or recycled material. If sold as scrap, waste, or for recycling, applicable duty...

19 CFR 10.91 - Prototypes used exclusively for product development and testing.

Code of Federal Regulations, 2012 CFR

2012-04-01

... prototypes or any part(s) of the prototypes may be sold as scrap, waste, or for recycling, as prescribed in..., or for recycling. This includes a prototype or any part thereof that is incorporated into another product, as scrap, waste, or recycled material. If sold as scrap, waste, or for recycling, applicable duty...

19 CFR 10.91 - Prototypes used exclusively for product development and testing.

Code of Federal Regulations, 2013 CFR

2013-04-01

... prototypes or any part(s) of the prototypes may be sold as scrap, waste, or for recycling, as prescribed in..., or for recycling. This includes a prototype or any part thereof that is incorporated into another product, as scrap, waste, or recycled material. If sold as scrap, waste, or for recycling, applicable duty...

Effect of Fly-Ash on Corrosion Resistance Characteristics of Rebar Embedded in Recycled Aggregate Concrete

NASA Astrophysics Data System (ADS)

Revathi, Purushothaman; Nikesh, P.

2018-04-01

In the frame of an extended research programme dealing with the utilization of recycled aggregate in concrete, the corrosion resistance characteristics of rebars embedded in recycled aggregate concrete is studied. Totally five series of concrete mixtures were prepared with fly-ash as replacement for cement in the levels of 10-30% by weight of cement. Corrosion studies by 90 days ponding test, linear polarization test and impressed voltage tests were carried out, in order to investigate whether corrosion behaviour of the rebars has improved due to the replacement of cement with fly-ash. Results showed that the replacement of cement with fly-ash in the range of 20-30% improves the corrosion resistance characteristics of recycled aggregate concrete.

Recycling attitudes and behavior among a clinic-based sample of low-income Hispanic women in southeast Texas.

PubMed

Pearson, Heidi C; Dawson, Lauren N; Radecki Breitkopf, Carmen

2012-01-01

We examined attitudes and behavior surrounding voluntary recycling in a population of low-income Hispanic women. Participants (N = 1,512) 18-55 years of age completed a self-report survey and responded to questions regarding household recycling behavior, recycling knowledge, recycling beliefs, potential barriers to recycling (transportation mode, time), acculturation, demographic characteristics (age, income, employment, marital status, education, number of children, birth country), and social desirability. Forty-six percent of participants (n = 810) indicated that they or someone else in their household recycled. In a logistic regression model controlling for social desirability, recycling behavior was related to increased age (P<0.05), lower acculturation (P<0.01), knowing what to recycle (P<0.01), knowing that recycling saves landfill space (P<0.05), and disagreeing that recycling takes too much time (P<0.001). A Sobel test revealed that acculturation mediated the relationship between recycling knowledge and recycling behavior (P<0.05). We offer new information on recycling behavior among Hispanic women and highlight the need for educational outreach and intervention strategies to increase recycling behavior within this understudied population.

Comparative assessment of different recycling methods of orthodontic brackets for clinical use.

PubMed

de Oliveira Correia, Ayla M; de Souza Matos, Felipe; Pilli Jóias, Renata; de Mello Rode, Sigmar; Cesar, Paulo F; Paranhos, Luiz R

2017-06-01

This study aimed to assess bond strength of the resin/bracket interface, under in-vitro shear stress, of metal brackets recycled by different clinical protocols. Sixty stainless steel orthodontic brackets were bonded on acrylic resin. The Transbond XT™ resin was applied at the base of the bracket aided by a matrix, obtaining 1 mm of thickness, and photoactivated with a LED device (40 s; 500 mW/cm2). Samples were randomly divided into four groups (N.=15) according to the reconditioning/recycling protocol: aluminum oxide (AO) 90 µm; hydrofluoric acid 60 s (HA60); hydrofluoric acid 120 s (HA120); hydrofluoric acid 60 s + silane (HA60S). After recycling, the resin was applied at the base of the bracket for shear testing in a universal testing machine (0.5 mm/min). After reconditioning/recycling, the surfaces were analyzed by Scanning Electron Microscopy. Data obtained after the shear test were subjected to ANOVA and Tukey's test (P<0.05). The AO group presented higher values of shear bond strength compared to the other reconditioning/recycling protocols (P<0.05). The HA120 and HA60S groups presented statistically similar results, but HA120 presented strength below the recommended limit. The recycling technique by aluminum oxide sandblasting was more effective for reconditioning orthodontic brackets when compared to the other protocols. The reconditioning technique with 10% hydrofluoric acid followed by the application of silane bonding agent may be used as an alternative protocol.

Quality control of recycled asphaltic concrete : final report.

DOT National Transportation Integrated Search

1982-07-01

This study examined the variations found in recycled asphaltic concrete mix based upon plant quality control data and verification testing. The data was collected from four recycled hot-mix projects constructed in 1981. All plant control and acceptan...

Recycled Coarse Aggregate Produced by Pulsed Discharge in Water

NASA Astrophysics Data System (ADS)

Namihira, Takao; Shigeishi, Mitsuhiro; Nakashima, Kazuyuki; Murakami, Akira; Kuroki, Kaori; Kiyan, Tsuyoshi; Tomoda, Yuichi; Sakugawa, Takashi; Katsuki, Sunao; Akiyama, Hidenori; Ohtsu, Masayasu

In Japan, the recycling ratio of concrete scraps has been kept over 98 % after the Law for the Recycling of Construction Materials was enforced in 2000. In the present, most of concrete scraps were recycled as the Lower Subbase Course Material. On the other hand, it is predicted to be difficult to keep this higher recycling ratio in the near future because concrete scraps increase rapidly and would reach to over 3 times of present situation in 2010. In addition, the demand of concrete scraps as the Lower Subbase Course Material has been decreased. Therefore, new way to reuse concrete scraps must be developed. Concrete scraps normally consist of 70 % of coarse aggregate, 19 % of water and 11 % of cement. To obtain the higher recycling ratio, the higher recycling ratio of coarse aggregate is desired. In this paper, a new method for recycling coarse aggregate from concrete scraps has been developed and demonstrated. The system includes a Marx generator and a point to hemisphere mesh electrode immersed in water. In the demonstration, the test piece of concrete scrap was located between the electrodes and was treated by the pulsed discharge. After discharge treatment of test piece, the recycling coarse aggregates were evaluated under JIS and TS and had enough quality for utilization as the coarse aggregate.

Full depth bituminous recycling of I-70, Thomas County, Kansas

DOT National Transportation Integrated Search

2004-01-01

In 1990, 13 full depth asphalt pavement test sections were built on a portion of I-70 in Thomas County, Kansas. Various combinations of hot mix and cold recycle mixes with different additives were used to build the test sections. Two of the test sect...

A Cryogen Recycler with Pulse Tube Cryocooler for Recondensing Helium and Nitrogen

NASA Astrophysics Data System (ADS)

Wang, C.; Lichtenwalter, B.

2015-12-01

We have developed a cryogen recycler using a 4 K pulse tube cryocooler for recondensing helium and nitrogen in a NMR magnet. The liquid helium cooled NMR magnet has a liquid nitrogen cooled radiation shield. The magnet boils off 0.84 L/day of liquid helium and 6 L/day of liquid nitrogen. The recycler is designed with both a liquid helium return tube and a liquid nitrogen return tube, which are inserted into the fill ports of liquid helium and nitrogen. Therefore the recycler forms closed loops for helium and nitrogen. A two-stage 4 K pulse tube cryocooler, Cryomech model PT407 (0.7W at 4.2 K), is selected for the recycler. The recycler was first tested with a Cryomech's test cryostat and resulted in the capacities of recondensing 8.2 L/day of nitrogen and liquefying 4 L/day of helium from room temperature gas. The recycler has been installed in the NMR magnet at University of Sydney since August, 2014 and continuously maintains a zero boil off for helium and nitrogen.

Leaching standards for mineral recycling materials--a harmonized regulatory concept for the upcoming German Recycling Decree.

PubMed

Susset, Bernd; Grathwohl, Peter

2011-02-01

In this contribution we give a first general overview of results of recent studies in Germany which focused on contaminant leaching from various materials and reactive solute transport in the unsaturated soil zone to identify the key factors for groundwater risk assessment. Based on these results we developed new and improved existing methods for groundwater risk assessment which are used to derive a new regulatory concept for the upcoming "Decree for the Requirements of the Use of Alternative Mineral Building Materials in Technical Constructions and for the Amendment of the Federal Soil Protection and Contaminated Sites Ordinance" of the German Federal Ministry of Environment. The new concept aims at a holistic and scientifically sound assessment of the use of mineral recycling materials (e.g., mineral waste, excavated soils, slag and ashes, recycling products, etc.) in technical constructions (e.g., road dams) and permanent applications (e.g., backfilling and landscaping) which is based on a mechanistic understanding of leaching and transport processes. Fundamental for risk assessment are leaching standards for the mineral recycling materials. For each application of mineral recycling materials specific maximum concentrations of a substance in the seepage water at the bottom of an application were calculated. Technical boundary conditions and policy conventions derived from the "German precautionary groundwater and soil protection policy" were accounted to prevent adverse environmental effects on the media soil and groundwater. This includes the concentration decline of highly soluble substances (e.g., chloride and sulphate), retardation or attenuation of solutes, accumulation of contaminants in sub-soils and the hydraulic properties of recycling materials used for specific applications. To decide whether the use of a mineral recycling material is possible in a specific application, the leaching qualities were evaluated based on column percolation tests with various samples and compared with application-specific maximum concentrations. In the upcoming federal decree this simplified concept is realized using detailed tables which classify the leaching quality of mineral recycling materials and demonstrate potential application. A quality assurance system will be mandatory which defines specific testing programs (material properties and limit concentrations to be tested, number and schedule of testing) for the different mineral recycling materials using standardized methods (column percolation test). Copyright © 2010 Elsevier Ltd. All rights reserved.

40 CFR 82.160 - Approved equipment testing organizations.

Code of Federal Regulations, 2011 CFR

2011-07-01

... PROGRAMS (CONTINUED) PROTECTION OF STRATOSPHERIC OZONE Recycling and Emissions Reduction § 82.160 Approved.... The application shall be mailed to: Section 608 Recycling Program Manager; Global Programs Division... verifying the performance of certified recycling and recovery equipment manufactured over the long term...

40 CFR 82.160 - Approved equipment testing organizations.

Code of Federal Regulations, 2010 CFR

2010-07-01

... PROGRAMS (CONTINUED) PROTECTION OF STRATOSPHERIC OZONE Recycling and Emissions Reduction § 82.160 Approved.... The application shall be mailed to: Section 608 Recycling Program Manager; Global Programs Division... verifying the performance of certified recycling and recovery equipment manufactured over the long term...

40 CFR 82.160 - Approved equipment testing organizations.

Code of Federal Regulations, 2014 CFR

2014-07-01

... PROGRAMS (CONTINUED) PROTECTION OF STRATOSPHERIC OZONE Recycling and Emissions Reduction § 82.160 Approved.... The application shall be mailed to: Section 608 Recycling Program Manager; Global Programs Division... verifying the performance of certified recycling and recovery equipment manufactured over the long term...

40 CFR 82.160 - Approved equipment testing organizations.

Code of Federal Regulations, 2012 CFR

2012-07-01

... PROGRAMS (CONTINUED) PROTECTION OF STRATOSPHERIC OZONE Recycling and Emissions Reduction § 82.160 Approved.... The application shall be mailed to: Section 608 Recycling Program Manager; Global Programs Division... verifying the performance of certified recycling and recovery equipment manufactured over the long term...

40 CFR 82.160 - Approved equipment testing organizations.

Code of Federal Regulations, 2013 CFR

2013-07-01

... PROGRAMS (CONTINUED) PROTECTION OF STRATOSPHERIC OZONE Recycling and Emissions Reduction § 82.160 Approved.... The application shall be mailed to: Section 608 Recycling Program Manager; Global Programs Division... verifying the performance of certified recycling and recovery equipment manufactured over the long term...

Recycling Attitudes and Behavior among a Clinic-Based Sample of Low-Income Hispanic Women in Southeast Texas

PubMed Central

Pearson, Heidi C.; Dawson, Lauren N.; Radecki Breitkopf, Carmen

2012-01-01

We examined attitudes and behavior surrounding voluntary recycling in a population of low-income Hispanic women. Participants (N = 1,512) 18–55 years of age completed a self-report survey and responded to questions regarding household recycling behavior, recycling knowledge, recycling beliefs, potential barriers to recycling (transportation mode, time), acculturation, demographic characteristics (age, income, employment, marital status, education, number of children, birth country), and social desirability. Forty-six percent of participants (n = 810) indicated that they or someone else in their household recycled. In a logistic regression model controlling for social desirability, recycling behavior was related to increased age (P<0.05), lower acculturation (P<0.01), knowing what to recycle (P<0.01), knowing that recycling saves landfill space (P<0.05), and disagreeing that recycling takes too much time (P<0.001). A Sobel test revealed that acculturation mediated the relationship between recycling knowledge and recycling behavior (P<0.05). We offer new information on recycling behavior among Hispanic women and highlight the need for educational outreach and intervention strategies to increase recycling behavior within this understudied population. PMID:22493693

Autoclaving and clinical recycling: effects on mechanical properties of orthodontic wires.

PubMed

Oshagh, M; Hematiyan, M R; Mohandes, Y; Oshagh, M R; Pishbin, L

2012-01-01

About half of the orthodontists recycle and reuse orthodontic wires because of their costs. So when talking about reuse and sterilization of wires, their effects on mechanical properties of wires should be clarified. The purpose of this study was to assess the effects of sterilization and clinical use on mechanical properties of stainless steel wires. Thirty stainless steel orthodontic wires were divided into three equal groups of control, autoclave (sterilized by autoclave), and recycle group (wires were used for orthodontic patients up to 4 weeks, cleaned by isopropyl alcohol and sterilized by autoclave). The mechanical properties (tensile test, three-point loading test for load-deflection curve) were determined. Fracture force, yield strength, stiffness and modulus of elasticity in recycle groups were significantly lower than the other groups (P < 0.05). Although recycle wires were softer than those of control group, relatively small differences and also various properties of available wires have obscured the clinical predictability of their application. There is seemingly no problem in terms of mechanical properties to recycle orthodontic wires.

Factors influencing the recycling rate under the volume-based waste fee system in South Korea.

PubMed

Park, Seejeen

2018-04-01

Since the early 2000s, the Republic of Korea (South Korea) has maintained its top-rank status for its municipal solid waste (MSW) recycling rate among OECD (Organization for Economic Cooperation and Development) member countries. The volume-based waste fee system (VWF) has been considered to be the major factor contributing to the high recycling performance, and extant research has verified the positive relationship between VWF adoption and the MSW recycling rate. Nevertheless, there exists a gap in the literature, as past research has focused more on testing the positive effects of VWF rather than on investigating the determinants of recycling rates after the adoption of VWF. The current study seeks to address this gap by investigating the various factors that affect recycling rates under the VWF system. More specifically, using data from 16 regions in South Korea over a period of 11 years, this study empirically tests the effects of VWF pricing, the citizen cost burden ratio for the VWF system, and pro-environmental behavior related to VWF on the recycling rate. The findings indicate that economic incentives such as cost savings on VWF plastic bag purchases and reduced burden from paying VWF expenses result in higher recycling rates. The findings also demonstrate that pro-environmental behavior in the VWF context positively affects the recycling rate. Copyright © 2018 Elsevier Ltd. All rights reserved.

The efficacy of a theory-based, participatory recycling intervention on a college campus.

PubMed

Largo-Wight, Erin; Johnston, Dedee DeLongpre; Wight, Jeff

2013-11-01

Recycling solid waste is an important primary prevention focus to protect environmental resources and human health. Recycling reduces energy consumption and emissions and the need to harvest raw material, which protects air, water, and land. In the study described in this article, the authors conducted an eight week field study to test the efficacy of an intervention aimed to increase can and bottle recycling on a college campus. Recycling volume was assessed in three campus buildings (two treatments and one control) over eight weeks. The control building had standard outdoor-only recycling. The treatment buildings had standard outdoor recycling plus four weeks with the treatment indoor recycling. Total can and bottle recycling volume increased 65%-250% in the treatment buildings compared to the control building. Recycling significantly increased in both the classroom (t = -2.9, p < .05) and administrative (t = -12.4, p < .001) treatment buildings compared to the control building (t = -.13, p = .91). Results suggest that convenience of receptacles alone, without education or additional promotion, resulted in significantly more recycling. Health promoters should prioritize efforts to make recycling easy and convenient.

Pre-Saturation Technique of the Recycled Aggregates: Solution to the Water Absorption Drawback in the Recycled Concrete Manufacture †

PubMed Central

García-González, Julia; Rodríguez-Robles, Desirée; Juan-Valdés, Andrés; Morán-del Pozo, Julia Mª; Guerra-Romero, M. Ignacio

2014-01-01

The replacement of natural aggregates by recycled aggregates in the concrete manufacturing has been spreading worldwide as a recycling method to counteract the large amount of construction and demolition waste. Although legislation in this field is still not well developed, many investigations demonstrate the possibilities of success of this trend given that concrete with satisfactory mechanical and durability properties could be achieved. However, recycled aggregates present a low quality compared to natural aggregates, the water absorption being their main drawback. When used untreated in concrete mix, the recycled aggregate absorb part of the water initially calculated for the cement hydration, which will adversely affect some characteristics of the recycled concrete. This article seeks to demonstrate that the technique of pre-saturation is able to solve the aforementioned problem. In order to do so, the water absorption of the aggregates was tested to determine the necessary period of soaking to bring the recycled aggregates into a state of suitable humidity for their incorporation into the mixture. Moreover, several concrete mixes were made with different replacement percentages of natural aggregate and various periods of pre-saturation. The consistency and compressive strength of the concrete mixes were tested to verify the feasibility of the proposed technique. PMID:28788188

SBS vs Inhouse Recycling Methods-An Invitro Evaluation

PubMed Central

Verma, Jaya Krishanan; Arun; Sundari, Shanta; Chandrasekhar, Shyamala; Kumar, Aravind

2015-01-01

Introduction In today’s world of economic crisis it is not feasible for an orthodontist to replace each and every debonded bracket with a new bracket- quest for an alternative thrives Orthodontist. The concept of recycling bracket for its reuse has evolved over a period of time. Orthodontist can send the brackets to various commercial recycling companies for recycling, but it’s impractical as these are complex procedures and require time and usage of a new bracket would seem more feasible. Thereby, in-house methods have been developed. The aim of the study was to determine the SBS (Shear Bond Strength) and to compare, evaluate the efficiency of in house recycling methods with that of the SBS of new brackets. Materials and Methods Five in–house-recycling procedures-Adhesive Grinding Method, Sandblasting Method, Thermal Flaming Method, Buchman method and Acid Bath Method were used in the present study. Initial part of the study included the use of UV/Vis spectrophotometer where in the absorption level of base of new stainless steel bracket is compared with the base of a recycled bracket. The difference seen in the UV absorbance can be attributed to the presence of adhesive remnant. For each recycling procedure the difference in UV absorption is calculated. New stainless steel brackets and recycled brackets were tested for its shear bond strength with Instron testing machine. Comparisons were made between shear bond strength of new brackets with that of recycled brackets. The last part of the study involved correlating the findings of UV/Vis spectrophotometer with the shear bond strength for each recycling procedure. Results Among the recycled brackets the Sandblasting technique showed the highest shear bond strength (19.789MPa) and the least was shown by the Adhesive Grinding method (13.809MPa). Conclusion The study concludes that sand blasting can be an effective choice among the 5 in house methods of recycling methods. PMID:26501002

Mechanical properties of concrete containing recycled concrete aggregate (RCA) and ceramic waste as coarse aggregate replacement

NASA Astrophysics Data System (ADS)

Khalid, Faisal Sheikh; Azmi, Nurul Bazilah; Sumandi, Khairul Azwa Syafiq Mohd; Mazenan, Puteri Natasya

2017-10-01

Many construction and development activities today consume large amounts of concrete. The amount of construction waste is also increasing because of the demolition process. Much of this waste can be recycled to produce new products and increase the sustainability of construction projects. As recyclable construction wastes, concrete and ceramic can replace the natural aggregate in concrete because of their hard and strong physical properties. This research used 25%, 35%, and 45% recycled concrete aggregate (RCA) and ceramic waste as coarse aggregate in producing concrete. Several tests, such as concrete cube compression and splitting tensile tests, were also performed to determine and compare the mechanical properties of the recycled concrete with those of the normal concrete that contains 100% natural aggregate. The concrete containing 35% RCA and 35% ceramic waste showed the best properties compared with the normal concrete.

Hanford Low-Activity Waste Processing: Demonstration of the Off-Gas Recycle Flowsheet - 13443

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ramsey, William G.; Esparza, Brian P.

2013-07-01

Vitrification of Hanford Low-Activity Waste (LAW) is nominally the thermal conversion and incorporation of sodium salts and radionuclides into borosilicate glass. One key radionuclide present in LAW is technetium-99. Technetium-99 is a low energy, long-lived beta emitting radionuclide present in the waste feed in concentrations on the order of 1-10 ppm. The long half-life combined with a high solubility in groundwater results in technetium-99 having considerable impact on performance modeling (as potential release to the environment) of both the waste glass and associated secondary waste products. The current Hanford Tank Waste Treatment and Immobilization Plant (WTP) process flowsheet calls formore » the recycle of vitrification process off-gas condensates to maximize the portion of technetium ultimately immobilized in the waste glass. This is required as technetium acts as a semi-volatile specie, i.e. considerable loss of the radionuclide to the process off-gas stream can occur during the vitrification process. To test the process flowsheet assumptions, a prototypic off-gas system with recycle capability was added to a laboratory melter (on the order of 1/200 scale) and testing performed. Key test goals included determination of the process mass balance for technetium, a non-radioactive surrogate (rhenium), and other soluble species (sulfate, halides, etc.) which are concentrated by recycling off-gas condensates. The studies performed are the initial demonstrations of process recycle for this type of liquid-fed melter system. This paper describes the process recycle system, the waste feeds processed, and experimental results. Comparisons between data gathered using process recycle and previous single pass melter testing as well as mathematical modeling simulations are also provided. (authors)« less

A comparison of the surface contaminants of handwritten recycled and printed electronic parenteral nutrition prescriptions and their transfer to bag surfaces during delivery to hospital wards.

PubMed

Austin, Peter David; Hand, Kieran Sean; Elia, Marinos

2014-02-01

Handwritten recycled paper prescription for parenteral nutrition (PN) may become a concentrated source of viable contaminants, including pathogens. This study examined the effect of using fresh printouts of electronic prescriptions on these contaminants. Cellulose sponge stick swabs with neutralizing buffer were used to sample the surfaces of PN prescriptions (n = 32 handwritten recycled; n = 32 printed electronic) on arrival to the pharmacy or following printing and PN prescriptions and bags packaged together during delivery (n = 38 handwritten recycled; n = 34 printed electronic) on arrival to hospital wards. Different media plates and standard microbiological procedures identified the type and number of contaminants. Staphylococcus aureus, fungi, and mold were infrequent contaminants. nonspecific aerobes more frequently contaminated handwritten recycled than printed electronic prescriptions (into pharmacy, 94% vs 44%, fisher exact test P .001; onto wards, 76% vs 50%, p = .028), with greater numbers of colony-forming units (CFU) (into pharmacy, median 130 [interquartile range (IQR), 65260] VS 0 [075], Mann-Whitney U test, P .001; onto wards, median 120 [15320] vs 10 [040], P = .001). packaging with handwritten recycled prescriptions led to more frequent nonspecific aerobic bag surface contamination (63% vs 41%, fisher exact test P = .097), with greater numbers of CFU (median 40 [IQR, 080] VS 0 [040], Mann-Whitney U test, P = .036). The use of printed electronic PN prescriptions can reduce microbial loads for contamination of surfaces that compromises aseptic techniques.

A study of drop-off recycling in Norman, Oklahoma: Behavior of recyclers and nonrecyclers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sims, J.L.; Everett, J.W.

The reality of growing negative public opinion to new landfills prompted a newfound popularity for recycling programs as an alternative to traditional waste management in municipalities. The purpose of this research is to examine the behavioral and attitudinal differences between recyclers and nonrecyclers. These differences were tested statistically based on recycling behavior data gathered through two independent questionnaire surveys, one administered through utility bill statements, the other administered directly by the first author. Data were collected on: contact with the recycling organization, demographics, participation, convenience, incentives, ideological agreement, and assessment rationale. Seven hypotheses were tested, addressing most aspects of themore » Environmental Collective Action model (ECA), first proposed by the second author in 1994. The surveys were administered to City of Norman, Oklahoma residents. Norman operates several drop-off centers within the city limits. The results of the analysis indicate that individuals do make the decision to participate based on the principles outlined in the model of participation. All seven hypotheses are supported by the data in both surveys.« less

Study on Effects of Different Replacement Rate on Bending Behavior of Big Recycled Aggregate Self Compacting Concrete

NASA Astrophysics Data System (ADS)

Li, Jing; Guo, Tiantian; Gao, Shuai; Jiang, Lin; Zhao, Zhijun; Wang, Yalin

2018-03-01

Big recycled aggregate self compacting concrete is a new type of recycled concrete, which has the advantages of low hydration heat and green environmental protection, but its bending behavior can be affected by different replacement rate. Therefor, in this paper, the research status of big Recycled aggregate self compacting concrete was systematically introduced, and the effect of different replacement rate of big recycled aggregate on failure mode, crack distribution and bending strength of the beam were studied through the bending behavior test of 4 big recycled aggregate self compacting concrete beams. The results show that: The crack distribution of the beam can be affected by the replacement rate; The failure modes of big recycled aggregate beams are the same as those of ordinary concrete; The plane section assumption is applicable to the big recycled aggregate self compacting concrete beam; The higher the replacement rate, the lower the bending strength of big recycled aggregate self compacting concrete beams.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aliaga, C., E-mail: caliaga@itene.com; Zhang, H.; Dobon, A.

Highlights: • Study of the influence of components of printed electronics in paper recycling. • Comparison between paper recycled with and without resistors, batteries and layouts. • Mechanical and optical properties are evaluated in paper handsheets obtained. • Tensile strength of recycled paper is slighted reduced by layouts. • Optical properties of recycled paper slightly varies with layouts and batteries. - Abstract: The aim of this paper is to analyse the effects of the presence of printed electronics on the paper waste streams and specifically on paper recyclability. The analysis is based on a case study focussed on envelopes formore » postal and courier services provided with these intelligent systems. The smart printed envelope of the study includes a combination of both conventional (thin flexible batteries and resistors) and printed electronic components (conductive track layout based on nanosilver ink). For this purpose, a comparison between envelopes with and without these components (batteries, resistors and conductive track layouts) was carried out through pilot scale paper recycling tests. The generation of rejects during the recycling process as well as the final quality of the recycled paper (mechanical and optical properties) were tested and quantitatively evaluated. The results show that resistors are retained during the screening process in the sieves and consequently they cannot end up in the final screened pulp. Therefore, mechanical and optical properties of the recycled paper are not affected. Nevertheless, inks from the conductive track layouts and batteries were partially dissolved in the process water. These substances were not totally retained in the sieving systems resulting in slight changes in the optical properties of the final recycled paper (variations are 7.2–7.5% in brightness, 8.5–10.7% in whiteness, 1.2–2.2% in L{sup ∗} values, 3.3–3.5% in opacity and 16.1–27% in yellowness). These variations are not in ranges able to cause problems in current paper recycling processes and restrict the use of recycled paper in current applications. Moreover, real impacts on industrial recycling are expected to be even significantly lower since the proportion of paper product with printed circuits in the current paper waste streams are much lower than the ones tested in this work. However, it should be underlined the fact that this situation may change over the next years due to the future developments in printed electronics and the gradual penetration of these types of devices in the market.« less

The influence of printed electronics on the recyclability of paper: a case study for smart envelopes in courier and postal services.

PubMed

Aliaga, C; Zhang, H; Dobon, A; Hortal, M; Beneventi, D

2015-04-01

The aim of this paper is to analyse the effects of the presence of printed electronics on the paper waste streams and specifically on paper recyclability. The analysis is based on a case study focussed on envelopes for postal and courier services provided with these intelligent systems. The smart printed envelope of the study includes a combination of both conventional (thin flexible batteries and resistors) and printed electronic components (conductive track layout based on nanosilver ink). For this purpose, a comparison between envelopes with and without these components (batteries, resistors and conductive track layouts) was carried out through pilot scale paper recycling tests. The generation of rejects during the recycling process as well as the final quality of the recycled paper (mechanical and optical properties) were tested and quantitatively evaluated. The results show that resistors are retained during the screening process in the sieves and consequently they cannot end up in the final screened pulp. Therefore, mechanical and optical properties of the recycled paper are not affected. Nevertheless, inks from the conductive track layouts and batteries were partially dissolved in the process water. These substances were not totally retained in the sieving systems resulting in slight changes in the optical properties of the final recycled paper (variations are 7.2-7.5% in brightness, 8.5-10.7% in whiteness, 1.2-2.2% in L(∗) values, 3.3-3.5% in opacity and 16.1-27% in yellowness). These variations are not in ranges able to cause problems in current paper recycling processes and restrict the use of recycled paper in current applications. Moreover, real impacts on industrial recycling are expected to be even significantly lower since the proportion of paper product with printed circuits in the current paper waste streams are much lower than the ones tested in this work. However, it should be underlined the fact that this situation may change over the next years due to the future developments in printed electronics and the gradual penetration of these types of devices in the market. Copyright © 2015 Elsevier Ltd. All rights reserved.

Evaluation of the effect of three innovative recyling methods on the shear bond strength of stainless steel brackets-an in vitro study.

PubMed

Gupta, Neeraj; Kumar, Dilip; Palla, Aparna

2017-04-01

Orthodontists are commonly faced with the decision of what to do with debonded or inaccurately positioned brackets. An economical option to this dilemma is to recycle the brackets. Many recycling methods have been proposed, but the optimal bond strength of these recycled brackets needs further evaluation. Objectives: To evaluate and compare the effect of three recycling methods: (i) Sandblasting (ii) Sandblasting / direct flaming (iii) Sandblasting /direct flaming /acid bath solution on shear bond strength (SBS) of stainless steel brackets. Eighty human premolars were bonded with premolar stainless steel brackets as per manufacturer's instructions. The teeth were divided into 4 groups (n=20): Recycling and initial debonding was not done in Control group (Group I). After initial bonding, the brackets in the rest of the three experimental groups were debonded and recycled by following methods: (i) Sandblasting (Group II) (ii) Sandblasting /direct flaming (Group III) (iii) Sandblasting /direct flaming /acid bath solution (Group IV). Further the recycled brackets were bonded. The specimens were then subjected to testing in a Universal machine. The evaluation of the variation of the shear bond strength (SBS) among test groups was done using one-way ANOVA test and inter-experimental group comparison was done by Newman-Keuls multiple post hoc procedure. Group I (8.6510±1.3943MPa) showed the highest bond strength followed by Group II (5.0185±0.9758MPa), Group IV (2.30±0.65MPa) and Group III (2.0455± 0.6196MPa). Statistically significant variations existed in the shear bond strength (SBS) in all groups analyzed except between Group III and Group IV. The following conclusions were drawn from the study: 1. Shear bond strength of new brackets is significantly higher than the recycled brackets. 2. Brackets sandblasted with 90µm aluminium oxide particle air-abrasion showed significantly higher shear bond strength compared to direct flaming/sandblasting and direct flaming/sandblasting/acid bath solution. 3. Sandblasting with 90µm aluminium oxide particle air-abrasion is the simplest, most efficient and hence, the preferred method of recycling debonded brackets. Key words: Orthodontic bracket, recycling, shear bond strength.

Multi-factor Effects on the Durability of Recycle Aggregate Concrete

NASA Astrophysics Data System (ADS)

Ma, Huan; Cui, Yu-Li; Zhu, Wen-Yu; Xie, Xian-Jie

2016-05-01

Recycled Aggregate Concrete (RAC) was prepared with different recycled aggregate replacement ratio, 0, 30%, 70% and 100% respectively. The performances of RAC were examined by the freeze-thaw cycle, carbonization and sulfate attack to assess the durability. Results show that test sequence has different effects on the durability of RAC; the durability is poorer when carbonation experiment was carried out firstly, and then other experiment was carried out again; the durability is better when recycled aggregate replacement ratio is 70%.

Viscoelastic behaviour of cold recycled asphalt mixes

NASA Astrophysics Data System (ADS)

Cizkova, Zuzana; Suda, Jan

2017-09-01

Behaviour of cold recycled mixes depends strongly on both the bituminous binder content (bituminous emulsion or foamed bitumen) and the hydraulic binder content (usually cement). In the case of cold recycled mixes rich in bitumen and with low hydraulic binder content, behaviour is close to the viscoelastic behaviour of traditional hot mix asphalt. With decreasing bituminous binder content together with increasing hydraulic binder content, mixes are characteristic with brittle behaviour, typical for concrete pavements or hydraulically bound layers. The behaviour of cold recycled mixes with low content of both types of binders is similar to behaviour of unbound materials. This paper is dedicated to analysing of the viscoelastic behaviour of the cold recycled mixes. Therefore, the tested mixes contained higher amount of the bituminous binder (both foamed bitumen and bituminous emulsion). The best way to characterize any viscoelastic material in a wide range of temperatures and frequencies is through the master curves. This paper includes interesting findings concerning the dependency of both parts of the complex modulus (elastic and viscous) on the testing frequency (which simulates the speed of heavy traffic passing) and on the testing temperature (which simulates the changing climate conditions a real pavement is subjected to).

40 CFR 82.169 - Suspension and revocation procedures.

Code of Federal Regulations, 2011 CFR

2011-07-01

... PROGRAMS (CONTINUED) PROTECTION OF STRATOSPHERIC OZONE Recycling and Emissions Reduction § 82.169... to act as a recovery/recycling equipment testing organization (under § 82.160), or reclaimer...

40 CFR 82.169 - Suspension and revocation procedures.

Code of Federal Regulations, 2010 CFR

2010-07-01

... PROGRAMS (CONTINUED) PROTECTION OF STRATOSPHERIC OZONE Recycling and Emissions Reduction § 82.169... to act as a recovery/recycling equipment testing organization (under § 82.160), or reclaimer...

40 CFR 82.169 - Suspension and revocation procedures.

Code of Federal Regulations, 2013 CFR

2013-07-01

... PROGRAMS (CONTINUED) PROTECTION OF STRATOSPHERIC OZONE Recycling and Emissions Reduction § 82.169... to act as a recovery/recycling equipment testing organization (under § 82.160), or reclaimer...

40 CFR 82.169 - Suspension and revocation procedures.

Code of Federal Regulations, 2012 CFR

2012-07-01

... PROGRAMS (CONTINUED) PROTECTION OF STRATOSPHERIC OZONE Recycling and Emissions Reduction § 82.169... to act as a recovery/recycling equipment testing organization (under § 82.160), or reclaimer...

40 CFR 82.169 - Suspension and revocation procedures.

Code of Federal Regulations, 2014 CFR

2014-07-01

... PROGRAMS (CONTINUED) PROTECTION OF STRATOSPHERIC OZONE Recycling and Emissions Reduction § 82.169... to act as a recovery/recycling equipment testing organization (under § 82.160), or reclaimer...

Laminated thermoplastic composite material from recycled high density polyethylene

NASA Technical Reports Server (NTRS)

Liu, Ping; Waskom, Tommy L.

1994-01-01

The design of a materials-science, educational experiment is presented. The student should understand the fundamentals of polymer processing and mechanical property testing of materials. The ability to use American Society for Testing and Materials (ASTM) standards is also necessary for designing material test specimens and testing procedures. The objectives of the experiment are (1) to understand the concept of laminated composite materials, processing, testing, and quality assurance of thermoplastic composites and (2) to observe an application example of recycled plastics.

Construction and demolition waste as a source of PVC for recycling.

PubMed

Prestes, Sabrina Moretto Darbello; Mancini, Sandro Donnini; Rodolfo, Antonio; Keiroglo, Raquel Carramillo

2012-02-01

Construction and demolition waste can contain considerable amounts of polyvinyl chloride (PVC). This paper describes a study of the recycling of PVC pipes collected from such waste materials. In a sorting facility for the specific disposal of construction and demolition waste, PVC was found to represent one-third of the plastics separated by workers. Pipes were sorted carefully to preclude any possible contamination by poly(ethylene terephthalate) (PET) found in the waste. The material was ground into two distinct particle sizes (final mesh of 12.7 and 8 mm), washed, dried and recycled. The average formulation of the pipes was determined based on ash content tests and used in the fabrication of a similar compound made mainly of virgin PVC. Samples of recycled pipes and of compound based on virgin material were subjected to tensile and impact tests and provided very similar results. These results are a good indication of the application potential of the recycled material and of the fact that longer grinding to obtain finer particles is not necessarily beneficial.

Developing effective messages about potable recycled water: The importance of message structure and content

NASA Astrophysics Data System (ADS)

Price, J.; Fielding, K. S.; Gardner, J.; Leviston, Z.; Green, M.

2015-04-01

Community opposition is a barrier to potable recycled water schemes. Effective communication strategies about such schemes are needed. Drawing on social psychological literature, two experimental studies are presented, which explore messages that improve public perceptions of potable recycled water. The Elaboration-Likelihood Model of information processing and attitude change is tested and supported. Study 1 (N = 415) premeasured support for recycled water, and trust in government information at Time 1. Messages varied in complexity and sidedness were presented at Time 2 (3 weeks later), and support and trust were remeasured. Support increased after receiving information, provided that participants received complex rather than simple information. Trust in government was also higher after receiving information. There was tentative evidence of this in response to two-sided messages rather than one-sided messages. Initial attitudes to recycled water moderated responses to information. Those initially neutral or ambivalent responded differently to simple and one-sided messages, compared to participants with positive or negative attitudes. Study 2 (N = 957) tested the effectiveness of information about the low relative risks, and/or benefits of potable recycled water, compared to control groups. Messages about the low risks resulted in higher support when the issue of recycled water was relevant. Messages about benefits resulted in higher perceived issue relevance, but did not translate into greater support. The results highlight the importance of understanding people's motivation to process information, and need to tailor communication to match attitudes and stage of recycled water schemes' development.

Fed-batch hydrolysate addition and cell separation by settling in high cell density lignocellulosic ethanol fermentations on AFEX™ corn stover in the Rapid Bioconversion with Integrated recycling Technology process.

PubMed

Sarks, Cory; Jin, Mingjie; Balan, Venkatesh; Dale, Bruce E

2017-09-01

The Rapid Bioconversion with Integrated recycling Technology (RaBIT) process uses enzyme and yeast recycling to improve cellulosic ethanol production economics. The previous versions of the RaBIT process exhibited decreased xylose consumption using cell recycle for a variety of different micro-organisms. Process changes were tested in an attempt to eliminate the xylose consumption decrease. Three different RaBIT process changes were evaluated in this work including (1) shortening the fermentation time, (2) fed-batch hydrolysate addition, and (3) selective cell recycling using a settling method. Shorting the RaBIT fermentation process to 11 h and introducing fed-batch hydrolysate addition eliminated any xylose consumption decrease over ten fermentation cycles; otherwise, decreased xylose consumption was apparent by the third cell recycle event. However, partial removal of yeast cells during recycle was not economical when compared to recycling all yeast cells.

Curing Effects on Interfacial Adhesion between Recycled Carbon Fiber and Epoxy Resin Heated by Microwave Irradiation

PubMed Central

Shimamoto, Daisuke; Hotta, Yuji

2018-01-01

The interfacial adhesion of recycled carbon fiber (CF) reinforced epoxy composite heated by microwave (MW) irradiation were investigated by changing the curing state of the epoxy resin. The recycled CF was recovered from the composite, which was prepared by vacuum-assisted resin transfer molding, by thermal degradation at 500 or 600 °C. Thermogravimetric analysis showed that the heating at 600 °C caused rough damage to the CF surface, whereas recycled CF recovered at 500 °C have few defects. The interfacial shear strength (IFSS) between recycled CF and epoxy resin was measured by a single-fiber fragmentation test. The test specimen was heated by MW after mixing the epoxy resin with a curing agent or pre-curing, in order to investigate the curing effects on the matrix resin. The IFSSs of the MW-irradiated samples were significantly varied by the curing state of the epoxy resin and the surface condition of recycled CF, resulting that they were 99.5 to 131.7% of oven heated samples Furthermore, rheological measurements showed that the viscosity and shrinking behaviors of epoxy resin were affected based on the curing state of epoxy resin before MW irradiation. PMID:29587422

Cyclic Behavior of Low Rise Concrete Shear Walls Containing Recycled Coarse and Fine Aggregates.

PubMed

Qiao, Qiyun; Cao, Wanlin; Qian, Zhiwei; Li, Xiangyu; Zhang, Wenwen; Liu, Wenchao

2017-12-07

In this study, the cyclic behaviors of low rise concrete shear walls using recycled coarse or fine aggregates were investigated. Eight low rise Recycled Aggregates Concrete (RAC) shear wall specimens were designed and tested under a cyclic loading. The following parameters were varied: replacement percentages of recycled coarse or fine aggregates, reinforcement ratio, axial force ratio and X-shaped rebars brace. The failure characteristics, hysteretic behavior, strength and deformation capacity, strain characteristics and stiffness were studied. Test results showed that the using of the Recycled Coarse Aggregates (RCA) and its replacement ratio had almost no influence on the mechanical behavior of the shear wall; however, the using of Recycled Fine Aggregates (RFA) had a certain influence on the ductility of the shear wall. When the reinforcement ratio increased, the strength and ductility also increased. By increasing the axial force ratio, the strength increased but the ductility decreased significantly. The encased brace had a significant effect on enhancing the RAC shear walls. The experimental maximum strengths were evaluated with existing design codes, it was indicated that the strength evaluation of the low rise RAC shear walls can follow the existing design codes of the conventional concrete shear walls.

Curing Effects on Interfacial Adhesion between Recycled Carbon Fiber and Epoxy Resin Heated by Microwave Irradiation.

PubMed

Tominaga, Yuichi; Shimamoto, Daisuke; Hotta, Yuji

2018-03-26

The interfacial adhesion of recycled carbon fiber (CF) reinforced epoxy composite heated by microwave (MW) irradiation were investigated by changing the curing state of the epoxy resin. The recycled CF was recovered from the composite, which was prepared by vacuum-assisted resin transfer molding, by thermal degradation at 500 or 600 °C. Thermogravimetric analysis showed that the heating at 600 °C caused rough damage to the CF surface, whereas recycled CF recovered at 500 °C have few defects. The interfacial shear strength (IFSS) between recycled CF and epoxy resin was measured by a single-fiber fragmentation test. The test specimen was heated by MW after mixing the epoxy resin with a curing agent or pre-curing, in order to investigate the curing effects on the matrix resin. The IFSSs of the MW-irradiated samples were significantly varied by the curing state of the epoxy resin and the surface condition of recycled CF, resulting that they were 99.5 to 131.7% of oven heated samples Furthermore, rheological measurements showed that the viscosity and shrinking behaviors of epoxy resin were affected based on the curing state of epoxy resin before MW irradiation.

Physical and thermal behavior of cement composites reinforced with recycled waste paper fibers

NASA Astrophysics Data System (ADS)

Hospodarova, Viola; Stevulova, Nadezda; Vaclavik, Vojtech; Dvorsky, Tomas

2017-07-01

In this study, three types of recycled waste paper fibers were used to manufacture cement composites reinforced with recycled cellulosic fibers. Waste cellulosic fibers in quantity of 0.2, 0.3, and 0.5 wt.% were added to cement mixtures. Physical properties such as density, water capillarity, water absorbability and thermal conductivity of fiber cement composites were studied after 28 days of hardening. However, durability of composites was tested after their water storage up to 90 days. Final results of tested properties of fiber cement composites were compared with cement reference sample without cellulosic fibers.

Potential applicability of stress wave velocity method on pavement base materials as a non-destructive testing technique

NASA Astrophysics Data System (ADS)

Mahedi, Masrur

Aggregates derived from natural sources have been used traditionally as the pavement base materials. But in recent times, the extraction of these natural aggregates has become more labor intensive and costly due to resource depletion and environmental concerns. Thus, the uses of recycled aggregates as the supplementary of natural aggregates are increasing considerably in pavement construction. Use of recycled aggregates such as recycled crushed concrete (RCA) and recycled asphalt pavement (RAP) reduces the rate of natural resource depletion, construction debris and cost. Although recycled aggregates could be used as a viable alternative of conventional base materials, strength characteristics and product variability limit their utility to a great extent. Hence, their applicability is needed to be evaluated extensively based on strength, stiffness and cost factors. But for extensive evaluation, traditionally practiced test methods are proven to be unreasonable in terms of time, cost, reliability and applicability. On the other hand, rapid non-destructive methods have the potential to be less time consuming and inexpensive along with the low variability of test results; therefore improving the reliability of estimated performance of the pavement. In this research work, the experimental program was designed to assess the potential application of stress wave velocity method as a non-destructive test in evaluating recycled base materials. Different combinations of cement treated recycled concrete aggregate (RAP) and recycled crushed concrete (RCA) were used to evaluate the applicability of stress wave velocity method. It was found that, stress wave velocity method is excellent in characterizing the strength and stiffness properties of cement treated base materials. Statistical models, based on P-wave velocity were derived for predicting the modulus of elasticity and compressive strength of different combinations of cement treated RAP, Grade-1 and Grade-2 materials. Two, three and four parameter modeling were also done for characterizing the resilient modulus response. It is anticipated that, derived correlations can be useful in estimating the strength and stiffness response of cement treated base materials with satisfactory level of confidence, if the P-wave velocity remains within the range of 500 ft/sec to 1500 ft/sec.

Interactive analysis of waste recycling and energy recovery program in a small-scale incinerator.

PubMed

Chen, Jeng-Chung; Chen, Wei-Hsin; Chang, Ni-Bin; Davila, Eric; Tsai, Cheng-Hsien

2005-09-01

Conflicting goals affecting solid waste management are explored in this paper to find the best implementation of resource recovery with a small-scale waste-to-energy process. Recycling paper and plastic material often leaves a shortage of thermal energy to support incineration that forces operators to supplement the process with auxiliary fuels. Although there are considerable profits to be made from material recovery, the increase of fuel usage causes conflict given that it is cost prohibitive. A series of trials performed on a small-scale 1.5-t/day incineration plant with a cyclone heat recovery system found that material recycling can impede performance. Experimental results are expressed as empirical regression formulas with regard to combustion temperature, energy transfer, and heat recovery. Process optimization is possible if the waste moisture content remains <30%. To test the robustness of the optimization analysis, a series of sensitivity analyses clarify the extent of material recycling needed with regard to plastic, paper, and metal. The experiments also test whether the moisture in the waste would decrease when recycling paper because of its exceptional capacity to absorb moisture. Results show that recycling paper is strongly recommended when the moisture content is >20%, whereas plastic recycling is not necessary at that moisture condition. Notably, plastic recovery reduces the heat needed to vaporize the water content of the solid waste, thus it is recommended only when the moisture content is <10%. For above-normal incineration temperatures, plastic recycling is encouraged, because it removes excess energy. Metal is confirmed as an overall priority in material recycling regardless of the moisture content of the incoming waste.

Design of a lamella settler for biomass recycling in continuous ethanol fermentation process.

PubMed

Tabera, J; Iznaola, M A

1989-04-20

The design and application of a settler to a continuous fermentation process with yeast recycle were studied. The compact lamella-type settler was chosen to avoid large volumes associated with conventional settling tanks. A rationale of the design method is covered. The sedimentation area was determined by classical batch settling rate tests and sedimentation capacity calculation. Limitations on the residence time of the microorganisms in the settler, rather than sludge thickening considerations, was the approach employed for volume calculation. Fermentation rate tests with yeast after different sedimentation periods were carried out to define a suitable residence time. Continuous cell recycle fermentation runs, performed with the old and new sedimentation devices, show that lamella settler improves biomass recycling efficiency, being the process able to operate at higher sugar concentrations and faster dilution rates.

Recycling and Self-Healing of Polybenzoxazines with Dynamic Sulfide Linkages.

PubMed

Arslan, Mustafa; Kiskan, Baris; Yagci, Yusuf

2017-07-12

In this work, a recycling and self-healing strategy for polybenzoxazines through both S-S bond cleavage-reformation reaction and supramolecular attractions is described. Both recyclable and self-healable polybenzoxazines can be prepared from low cost chemicals with a simple procedure in only 30 minutes. For this purpose, inverse vulcanization of poly(propylene oxide)benzoxazine (PPOB) and diallybenzoxazine (B-al) with elemental sulfur was performed at 185 °C. The obtained cross-linked polymer films exhibited thermally driven recycling ability up to 5 cycles. Moreover, the self-healing ability of a test specimen was shown. Spectral characterizations, thermal stability and fracture toughness of the films were investigated after each recycling.

An Empirical Test of an Expanded Version of the Theory of Planned Behavior in Predicting Recycling Behavior on Campus

ERIC Educational Resources Information Center

Largo-Wight, Erin; Bian, Hui; Lange, Lori

2012-01-01

Background: The study and promotion of environmental health behaviors, such as recycling, is an emerging focus in public health. Purpose: This study was designed to examine the determinants of recycling intention on a college campus. Methods: Undergraduate students (N=189) completed a 35-item web-based survey past findings and an expanded version…

Post-consumer contamination in high-density polyethylene (HDPE) milk bottles and the design of a bottle-to-bottle recycling process.

PubMed

Welle, F

2005-10-01

Six hundred conventional recycled HDPE flake samples, which were recollected and sorted in the UK, were screened for post-consumer contamination levels. Each analysed sample consisted of 40-50 individual flakes so that the amount of analysed individual containers was in the range 24,000-30,000 post-consumer milk bottles. Predominant contaminants in hot-washed flake samples were unsaturated oligomers, which can be also be found in virgin high-density polyethylene (HDPE) pellet samples used for milk bottle production. In addition, the flavour compound limonene, the degradation product of antioxidant additives di-tert-butylphenol and low amounts of saturated oligomers were found in higher concentrations in the post-consumer samples in comparison with virgin HDPE. However, the overall concentrations in post-consumer recycled samples were similar to or lower than concentration ranges in comparison with virgin HDPE. Contamination with other HDPE untypical compounds was rare and was in most cases related to non-milk bottles, which are <2.1% of the input material of the recycling process. The maximum concentration found in one sample of 1 g was estimated as 130 mg kg(-1), which corresponds to a contamination of 5200-6500 mg kg(-1) in the individual bottle. The recycling process investigated was based on an efficient sorting process, a hot-washing of the ground bottles, and a further deep-cleaning of the flakes with high temperatures and vacuum. Based on the fact that the contamination levels of post-consumer flake samples are similar to virgin HDPE and on the high cleaning efficiency of the super-clean recycling process especially for highly volatile compounds, the recycling process investigated is suitable for recycled post-consumer HDPE bottles for direct food-contact applications. However, hand-picking after automatically sorting is recommended to decrease the amount of non-milk bottles. The conclusions for suitability are valid, provided that the migration testing of recyclate contains milk bottles up to 100% and that both shelf-life testing and sensorial testing of the products are successful, which are topics of further investigations.

Evaluation of the effect of three innovative recyling methods on the shear bond strength of stainless steel brackets-an in vitro study

PubMed Central

Kumar, Dilip; Palla, Aparna

2017-01-01

Background Orthodontists are commonly faced with the decision of what to do with debonded or inaccurately positioned brackets. An economical option to this dilemma is to recycle the brackets. Many recycling methods have been proposed, but the optimal bond strength of these recycled brackets needs further evaluation. Objectives: To evaluate and compare the effect of three recycling methods: (i) Sandblasting (ii) Sandblasting / direct flaming (iii) Sandblasting /direct flaming /acid bath solution on shear bond strength (SBS) of stainless steel brackets. Material and Methods Eighty human premolars were bonded with premolar stainless steel brackets as per manufacturer’s instructions. The teeth were divided into 4 groups (n=20): Recycling and initial debonding was not done in Control group (Group I). After initial bonding, the brackets in the rest of the three experimental groups were debonded and recycled by following methods: (i) Sandblasting (Group II) (ii) Sandblasting /direct flaming (Group III) (iii) Sandblasting /direct flaming /acid bath solution (Group IV). Further the recycled brackets were bonded. The specimens were then subjected to testing in a Universal machine. The evaluation of the variation of the shear bond strength (SBS) among test groups was done using one-way ANOVA test and inter-experimental group comparison was done by Newman-Keuls multiple post hoc procedure. Results Group I (8.6510±1.3943MPa) showed the highest bond strength followed by Group II (5.0185±0.9758MPa), Group IV (2.30±0.65MPa) and Group III (2.0455± 0.6196MPa). Statistically significant variations existed in the shear bond strength (SBS) in all groups analyzed except between Group III and Group IV. Conclusions The following conclusions were drawn from the study: 1. Shear bond strength of new brackets is significantly higher than the recycled brackets. 2. Brackets sandblasted with 90µm aluminium oxide particle air-abrasion showed significantly higher shear bond strength compared to direct flaming/sandblasting and direct flaming/sandblasting/acid bath solution. 3. Sandblasting with 90µm aluminium oxide particle air-abrasion is the simplest, most efficient and hence, the preferred method of recycling debonded brackets. Key words:Orthodontic bracket, recycling, shear bond strength. PMID:28469821

Recycling cycle of materials applied to acrylonitrile-butadiene-styrene/policarbonate blends with styrene-butadiene-styrene copolymer addition

NASA Astrophysics Data System (ADS)

Cândido, L. H. A.; Ferreira, D. B.; Júnior, W. Kindlein; Demori, R.; Mauler, R. S.

2014-05-01

The scope of this research is the recycling of polymers from mobile phones hulls discarded and the performance evaluation when they are submitted to the Recycling Cycle of Materials (RCM). The studied material was the ABS/PC blend in a 70/30 proportion. Different compositions were evaluated adding virgin material, recycled material and using the copolymer SBS as impact modifier. In order to evaluate the properties of material's composition, the samples were characterized by TGA, FTIR, SEM, IZOD impact strength and tensile strength tests. At the first stage, the presented results suggest the composition containing 25% of recycled material and 5% of SBS combines good mechanical performance to the higher content of recycled material and lower content of impact modifier providing major benefits to recycling plans. Five cycles (RCM) were applied in the second stage; they evidenced a decrease trend considering the impact strength. At first and second cycle the impact strength was higher than reference material (ABS/PC blend) and from the fourth cycle it was lower. The superiority impact strength in the first and second cycles can be attributed to impact modifier effect. The thermal tests and the spectrometry didn't show the presence of degradation process in the material and the TGA curves demonstrated the process stability. The impact surface of each sample was observed at SEM. The microstructures are not homogeneous presenting voids and lamellar appearance, although the outer surface presents no defects, demonstrating good moldability. The present work aims to assess the life cycle of the material from the successive recycling processes.

Evaluation of recycled concrete aggregates for their suitability in construction activities: An experimental study.

PubMed

Puthussery, Joseph V; Kumar, Rakesh; Garg, Anurag

2017-02-01

Construction and demolition waste disposal is a major challenge in developing nations due to its ever increasing quantities. In this study, the recycling potential of waste concrete as aggregates in construction activities was studied. The metal leaching from the recycled concrete aggregates (RCA) collected from the demolition site of a 50year old building, was evaluated by performing three different leaching tests (compliance, availability and Toxic Characteristic Leaching Procedure). The metal leaching was found mostly within the permissible limit except for Hg. Several tests were performed to determine the physical and mechanical properties of the fine and coarse aggregates produced from recycled concrete. The properties of recycled aggregates were found to be satisfactory for their utilization in road construction activities. The suitability of using recycled fine and coarse aggregates with Portland pozzolanic cement to make a sustainable and environmental friendly concrete mix design was also analyzed. No significant difference was observed in the compressive strength of various concrete mixes prepared by natural and recycled aggregates. However, only the tensile strength of the mix prepared with 25% recycled fine aggregates was comparable to that of the control concrete. For other mixes, the tensile strength of the concrete was found to drop significantly. In summary, RCA should be considered seriously as a building material for road construction, mass concrete works, lightly reinforced sections, etc. The present work will be useful for the waste managers and policy makers particularly in developing nations where proper guidelines are still lacking. Copyright © 2016 Elsevier Ltd. All rights reserved.

Field Performance of Recycled Plastic Foundation for Pipeline

PubMed Central

Kim, Seongkyum; Lee, Kwanho

2015-01-01

The incidence of failure of embedded pipelines has increased in Korea due to the increasing applied load and the improper compaction of bedding and backfill materials. To overcome these problems, a prefabricated lightweight plastic foundation using recycled plastic was developed for sewer pipelines. A small scale laboratory chamber test and two field tests were conducted to verify its construction workability and performance. From the small scale laboratory chamber test, the applied loads at 2.5% and 5.0% of deformation were 3.45 kgf/cm2 and 5.85 kgf/cm2 for Case S1, and 4.42 kgf/cm2 and 6.43 kgf/cm2 for Case S2, respectively. From the first field test, the vertical deformation of the recycled plastic foundation (Case A2) was very small. According to the analysis based on the PE pipe deformation at the connection (CN) and at the center (CT), the pipe deformation at each part for Case A1 was larger than that for Case A2, which adopted the recycled lightweight plastic foundation. From the second field test, the measured maximum settlements of Case B1 and Case B2 were 1.05 cm and 0.54 cm, respectively. The use of a plastic foundation can reduce the settlement of an embedded pipeline and be an alternative construction method.

Recycled sand in lime-based mortars.

PubMed

Stefanidou, M; Anastasiou, E; Georgiadis Filikas, K

2014-12-01

The increasing awareness of the society about safe guarding heritage buildings and at the same time protecting the environment promotes strategies of combining principles of restoration with environmentally friendly materials and techniques. Along these lines, an experimental program was carried out in order to investigate the possibility of producing repair, lime-based mortars used in historic buildings incorporating secondary materials. The alternative material tested was recycled fine aggregates originating from mixed construction and demolition waste. Extensive tests on the raw materials have been performed and mortar mixtures were produced using different binding systems with natural, standard and recycled sand in order to compare their mechanical, physical and microstructure properties. The study reveals the improved behavior of lime mortars, even at early ages, due to the reaction of lime with the Al and Si constituents of the fine recycled sand. The role of the recycled sand was more beneficial in lime mortars rather than the lime-pozzolan or lime-pozzolan-cement mortars as a decrease in their performance was recorded in the latter cases due to the mortars' structure. Copyright © 2014 Elsevier Ltd. All rights reserved.

Recyclability of Concrete Pavement Incorporating High Volume of Fly Ash.

PubMed

Yoshitake, Isamu; Ishida, Takeo; Fukumoto, Sunao

2015-08-21

Recyclable concrete pavement was made from fly ash and crushed limestone sand and gravel as aggregates so that the concrete pavement could be recycled to raw materials for cement production. With the aim to use as much fly ash as possible for the sustainable development of society, while achieving adequate strength development, pavement concrete having a cement-replacement ratio of 40% by mass was experimentally investigated, focusing on the strength development at an early age. Limestone powder was added to improve the early strength; flexural strength at two days reached 3.5 MPa, the minimum strength for traffic service in Japan. The matured fly ash concrete made with a cement content of 200 kg/m3 achieved a flexural strength almost equal to that of the control concrete without fly ash. Additionally, Portland cement made from the tested fly ash concrete was tested to confirm recyclability, with the cement quality meeting the Japanese classification of ordinary Portland cement. Limestone-based recyclable fly ash concrete pavement is, thus, a preferred material in terms of sustainability.

Recyclability of Concrete Pavement Incorporating High Volume of Fly Ash

PubMed Central

Yoshitake, Isamu; Ishida, Takeo; Fukumoto, Sunao

2015-01-01

Recyclable concrete pavement was made from fly ash and crushed limestone sand and gravel as aggregates so that the concrete pavement could be recycled to raw materials for cement production. With the aim to use as much fly ash as possible for the sustainable development of society, while achieving adequate strength development, pavement concrete having a cement-replacement ratio of 40% by mass was experimentally investigated, focusing on the strength development at an early age. Limestone powder was added to improve the early strength; flexural strength at two days reached 3.5 MPa, the minimum strength for traffic service in Japan. The matured fly ash concrete made with a cement content of 200 kg/m3 achieved a flexural strength almost equal to that of the control concrete without fly ash. Additionally, Portland cement made from the tested fly ash concrete was tested to confirm recyclability, with the cement quality meeting the Japanese classification of ordinary Portland cement. Limestone-based recyclable fly ash concrete pavement is, thus, a preferred material in terms of sustainability. PMID:28793518

Testicular membrane lipid damage by complex mixture of leachate from municipal battery recycling site as indication of idiopathic male infertility in rat

PubMed Central

Oboh, Ganiyu; Akindahunsi, Akintunde A.

2013-01-01

Leachate from a municipal battery recycling site is a potent source of mixed-metal released into the environment. The present study investigated the degree at which mixed-metal exposure to the municipal auto-battery leachate (MABL) and to the Elewi Odo municipal auto-battery recycling site leachate (EOMABRL) affected the lipid membrane of the testes in in vitro experiment. The results showed elevated level of mixed-metals over the permissible levels in drinking water, as recommended by regulatory authorities. In the leachate samples, the levels of malondialdehyde (MDA), a biomarker of lipid damage, was significantly (p<0.05) increased in rat testes in a dose-dependent manner. MDA induced by the municipal auto-battery leachate (MABL) was significantly (p<0.05) higher than the leachate from Elewi Odo municipal auto-battery recycling site (EOMABRL). The testicular lipid membrane capacity was compromised following treatment with leachate from the municipal battery recycling site, implicating mixed-metal exposure as the causative agent of testicular damage and male infertility. PMID:24678257

Testicular membrane lipid damage by complex mixture of leachate from municipal battery recycling site as indication of idiopathic male infertility in rat.

PubMed

Akintunde, Jacob K; Oboh, Ganiyu; Akindahunsi, Akintunde A

2013-12-01

Leachate from a municipal battery recycling site is a potent source of mixed-metal released into the environment. The present study investigated the degree at which mixed-metal exposure to the municipal auto-battery leachate (MABL) and to the Elewi Odo municipal auto-battery recycling site leachate (EOMABRL) affected the lipid membrane of the testes in in vitro experiment. The results showed elevated level of mixed-metals over the permissible levels in drinking water, as recommended by regulatory authorities. In the leachate samples, the levels of malondialdehyde (MDA), a biomarker of lipid damage, was significantly (p<0.05) increased in rat testes in a dose-dependent manner. MDA induced by the municipal auto-battery leachate (MABL) was significantly (p<0.05) higher than the leachate from Elewi Odo municipal auto-battery recycling site (EOMABRL). The testicular lipid membrane capacity was compromised following treatment with leachate from the municipal battery recycling site, implicating mixed-metal exposure as the causative agent of testicular damage and male infertility.

Quality Assessment of Mixed and Ceramic Recycled Aggregates from Construction and Demolition Wastes in the Concrete Manufacture According to the Spanish Standard.

PubMed

Rodríguez-Robles, Desirée; García-González, Julia; Juan-Valdés, Andrés; Morán-Del Pozo, Julia Mª; Guerra-Romero, Manuel I

2014-08-13

Construction and demolition waste (CDW) constitutes an increasingly significant problem in society due to the volume generated, rendering sustainable management and disposal problematic. The aim of this study is to identify a possible reuse option in the concrete manufacturing for recycled aggregates with a significant ceramic content: mixed recycled aggregates (MixRA) and ceramic recycled aggregates (CerRA). In order to do so, several tests are conducted in accordance with the Spanish Code on Structural Concrete (EHE-08) to determine the composition in weight and physic-mechanical characteristics (particle size distributions, fine content, sand equivalent, density, water absorption, flakiness index, and resistance to fragmentation) of the samples for the partial inclusion of the recycled aggregates in concrete mixes. The results of these tests clearly support the hypothesis that this type of material may be suitable for such partial replacements if simple pretreatment is carried out. Furthermore, this measure of reuse is in line with European, national, and regional policies on sustainable development, and presents a solution to the environmental problem caused by the generation of CDW.

Recycling of rubble from building demolition for low-shrinkage concretes.

PubMed

Corinaldesi, Valeria; Moriconi, Giacomo

2010-04-01

In this project concrete mixtures were prepared that were characterized by low ductility due to desiccation by using debris from building demolition, which after a suitable treatment was used as aggregate for partial replacement of natural aggregates. The recycled aggregate used came from a recycling plant, in which rubble from building demolition was selected, crushed, cleaned, sieved, and graded. Such aggregates are known to be more porous as indicated by the Saturated Surface Dry (SSD) moisture content. The recycled concrete used as aggregates were added to the concrete mixture in order to study their influence on the fresh and hardened concrete properties. They were added either after water pre-soaking or in dry condition, in order to evaluate the influence of moisture in aggregates on the performance of concrete containing recycled aggregate. In particular, the effect of internal curing, due to the use of such aggregates, was studied. Concrete behavior due to desiccation under dehydration was studied by means of both drying shrinkage test and German angle test, through which shrinkage under the restrained condition of early age concrete can be evaluated. Copyright 2009 Elsevier Ltd. All rights reserved.

Plastic Recycling Experiments in Materials Education

NASA Technical Reports Server (NTRS)

Liu, Ping; Waskom, Tommy L.

1996-01-01

The objective of this project was to introduce a series of plastic recycling experiments to students in materials-related courses such as materials science, material technology and materials testing. With the plastic recycling experiments, students not only can learn the fundamentals of plastic processing and properties as in conventional materials courses, but also can be exposed to the issue of materials life cycle and the impact on society and environment.

Analysis of Shear Bond Strength and Morphology of Er:YAG Laser-Recycled Ceramic Orthodontic Brackets.

PubMed

Han, Ruo-qiao; Yang, Kai; Ji, Ling-fei; Ling, Chen

2016-01-01

The aim of this study was to compare the recycling of deboned ceramic brackets via an Er:YAG laser or via the traditional chairside processing methods of flaming and sandblasting; shear bond strength and morphological changes were evaluated in recycled brackets versus new brackets. 3M Clarity Self-Ligating Ceramic Brackets with a microcrystalline base were divided into groups subjected to flaming, sandblasting, or exposure to an Er:YAG laser. New ceramic brackets served as a control group. Shear bond strengths were determined with an Electroforce test machine and tested for statistical significance through analysis of variance. Morphological examinations of the recycled ceramic bracket bases were conducted with scanning electron microscopy and confocal laser scanning microscopy. Residue on the bracket base was analyzed with Raman spectroscopy. Faded, dark adhesive was left on recycled bracket bases processed via flaming. Adhesive was thoroughly removed by both sandblasting and exposure to an Er:YAG laser. Compared with new brackets, shear bond strength was lower after sandblasting (p < 0.05), but not after exposure to an Er:YAG laser. The Er:YAG laser caused no damage to the bracket. Er:YAG lasers effectively remove adhesive from the bases of ceramic brackets without damaging them; thus, this method may be preferred over other recycling methods.

Characterization and Modeling of Recycled Pavement Sections

DOT National Transportation Integrated Search

2017-12-01

Because of its documented cost and environmental benefits, cold central plant recycling (CCPR) has attracted the interest of local and state departments of transportation. In 2015 two test pavement sections with CCPR as base layers were constructed a...

RFTA (Recycle Filter Tank Assembly) test fill

NASA Image and Video Library

2009-06-02

ISS020-E-005984 (2 June 2009) --- European Space Agency astronaut Frank De Winne, Expedition 20 flight engineer, works with the Water Recovery System Recycle Filter Tank Assembly (RFTA) in the Destiny laboratory of the International Space Station.

Durability assessment of recycled concrete aggregates for use in new concrete.

DOT National Transportation Integrated Search

2012-06-01

The primary goal of this research project was to investigate the long-term durability of concrete incorporating : recycled concrete aggregate (RCA) through accelerated laboratory testing. Overall it was found that modifications to : standard aggregat...

Migration of mineral oil from party plates of recycled paperboard into foods: 1. Is recycled paperboard fit for the purpose? 2. Adequate testing procedure.

PubMed

Dima, Giovanna; Verzera, Antonella; Grob, Koni

2011-11-01

Party plates made of recycled paperboard with a polyolefin film on the food contact surface (more often polypropylene than polyethylene) were tested for migration of mineral oil into various foods applying reasonable worst case conditions. The worst case was identified as a slice of fried meat placed onto the plate while hot and allowed to cool for 1 h. As it caused the acceptable daily intake (ADI) specified by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) to be exceeded, it is concluded that recycled paperboard is generally acceptable for party plates only when separated from the food by a functional barrier. Migration data obtained with oil as simulant at 70°C was compared to the migration into foods. A contact time of 30 min was found to reasonably cover the worst case determined in food.

Sequential recycling of enzymatic lipid-extracted hydrolysate in fermentations with a thraustochytrid.

PubMed

Lowrey, Joshua; Armenta, Roberto E; Brooks, Marianne S

2016-06-01

This study extends the findings of prior studies proposing and validating nutrient recycling for the heterotrophic microalgae, Thraustochytrium sp. (T18), grown in optimized fed-batch conditions. Sequential nutrient recycling of enzymatically-derived hydrolysate in fermentors succeeded at growing the tested thraustochytrid strain, with little evidence of inhibition or detrimental effects upon culture health. The average maximum biomass obtained in the recycled hydrolysate was 63.68±1.46gL(-1) in 90h the first recycle followed by 65.27±1.15gL(-1) in 90h in the subsequent recycle of the same material. These compared to 58.59gL(-1) and 64.92gL(-1) observed in fresh media in the same time. Lipid production was slightly impaired, however, with a maximum total fatty acid content of 62.2±0.30% in the recycled hydrolysate compared to 69.4% in fresh control media. Copyright © 2016 Elsevier Ltd. All rights reserved.

Recycling cellulases for cellulosic ethanol production at industrial relevant conditions: potential and temperature dependency at high solid processes.

PubMed

Lindedam, Jane; Haven, Mai Østergaard; Chylenski, Piotr; Jørgensen, Henning; Felby, Claus

2013-11-01

Different versions of two commercial cellulases were tested for their recyclability of enzymatic activity at high dry matter processes (12% or 25% DM). Recyclability was assessed by measuring remaining enzyme activity in fermentation broth and the ability of enzymes to hydrolyse fresh, pretreated wheat straw. Industrial conditions were used to study the impact of hydrolysis temperature (40 or 50°C) and residence time on recyclability. Enzyme recycling at 12% DM indicated that hydrolysis at 50°C, though ideal for ethanol yield, should be kept short or carried out at lower temperature to preserve enzymatic activity. Best results for enzyme recycling at 25% DM was 59% and 41% of original enzyme load for a Celluclast:Novozyme188 mixture and a modern cellulase preparation, respectively. However, issues with stability of enzymes and their strong adsorption to residual solids still pose a challenge for applicable methods in enzyme recycling. Copyright © 2013 Elsevier Ltd. All rights reserved.

Stripping in hot mix asphalt produced by aggregates from construction and demolition waste.

PubMed

Pérez, I; Pasandín, A R; Gallego, J

2012-01-01

This paper analyses the effect of water on the durability of hot asphalt mixtures made with recycled aggregates from construction and demolition debris. Indirect tensile stress tests were carried out to evaluate stripping behaviour. The mixtures tested were fabricated with 0, 20, 40 and 60% recycled aggregates. Two types of natural aggregates were used: schist and calcite dolomite. An increase in the percentage of recycled aggregates was found to produce a decrease in the tensile stress ratio of the hot asphalt mixtures. To study this phenomenon, two and three factor analyses of variance (ANOVA) were performed with indirect tensile stress being used as the dependent variable. The factors studied were the percentage of recycled aggregates (0, 20, 40 and 60%), the moisture state (dry, wet) and the type of natural aggregate (schist, calcite). On the basis of the ANOVA results, it was found that the most important factor affecting resistance was the moisture state (dry, wet) of the specimens. The percentage of recycled aggregate also affected indirect tensile stress, especially in the dry state. The type of natural aggregate did not have a significant effect on indirect tensile stress. The hot asphalt mixture specimens made with different percentages of recycled aggregates from construction and demolition debris and of natural quarry aggregates showed poor stripping behaviour. This stripping behaviour can be related to both the poor adhesion of the recycled aggregates and the high absorption of the mortar of cement adhered to them.

A 12 month clinical study of bond failures of recycled versus new stainless steel orthodontic brackets.

PubMed

Cacciafesta, Vittorio; Sfondrini, Maria Francesca; Melsen, Birte; Scribante, Andrea

2004-08-01

The purpose of this prospective longitudinal randomized study was to compare the clinical performance of recycled brackets with that of new stainless steel brackets (Orthos). Twenty patients treated with fixed appliances were included in the investigation. Using a 'split-mouth' design, the dentition of each patient was divided into four quadrants. In 11 randomly selected patients, the maxillary left and mandibular right quadrants were bonded with recycled brackets, and the remaining quadrants with new stainless steel brackets. In the other nine patients the quadrants were inverted. Three hundred and ten stainless steel brackets were examined: 156 were recycled and the remaining 154 were new. All the brackets were bonded with a self-cured resin-modified glass ionomer (GC Fuji Ortho). The number, cause, and date of bracket failures were recorded over 12 months. Statistical analysis was performed by means of a paired t-test, Kaplan-Meier survival estimates, and the log-rank test. No statistically significant differences were found between: (a) the total bond failure rate of recycled and new stainless steel brackets; (b) the upper and lower arches; (c) the anterior and posterior segments. These findings demonstrate that recycling metallic orthodontic brackets can be of benefit to the profession, both economically and ecologically, as long as the orthodontist is aware of the various aspects of the recycling methods, and that patients are informed about the type of bracket that will be used for their treatment.

Investigations on Fresh and Hardened Properties of Recycled Aggregate Self Compacting Concrete

NASA Astrophysics Data System (ADS)

Revathi, P.; Selvi, R. S.; Velin, S. S.

2013-09-01

In the recent years, construction and demolition waste management issues have attracted the attention from researchers around the world. In the present study, the potential usage of recycled aggregate obtained from crushed demolition waste for making self compacting concrete (SCC) was researched. The barriers in promoting the use of recycled material in new construction are also discussed. In addition, the results of an experimental study involving the use of recycled concrete aggregate as coarse aggregates for producing self-compacting concrete to study their flow and strength characteristics are also presented. Five series of mixture were prepared with 0, 25, 50, 75, and 100 % coarse recycled aggregate adopting Nan Su's mix proportioning method. The fresh concrete properties were evaluated through the slump flow, J-ring and V-funnel tests. Compressive and tensile strengths were also determined. The results obtained showed that SCC could be successfully developed by incorporating recycled aggregates.

Effect of IN718 Recycled Powder Reuse on Properties of Parts Manufactured by Means of Selective Laser Melting

NASA Astrophysics Data System (ADS)

Ardila, L. C.; Garciandia, F.; González-Díaz, J. B.; Álvarez, P.; Echeverria, A.; Petite, M. M.; Deffley, R.; Ochoa, J.

Powder quality control is essential to obtain parts with suitable mechanical properties in Selective Laser Melting manufacturing technique. One of the most important advantages of suchtechnique is that it allows an efficient use of the material, due to the possibility to recycle and reuse un-melted powder. Nevertheless, powder material properties may change due to repeated recycling, affecting this way the mechanicalbehavior of parts. In this paper the effect of powder reuse on its quality and on the mechanical properties of the resulting melted parts is studied via self-developed recycling methodology. The material considered for investigation was IN718, a nickel superalloy widely used in industry. After recycling powder up to 14 times, no significant changes were observed in powder and test parts properties. The results obtained in this work will help to validate powder recycling methodology for its use in current industrial Selective Laser Melting manufacturing.

40 CFR Appendix C to Subpart F of... - Method for Testing Recovery Devices for Use With Small Appliances

Code of Federal Regulations, 2014 CFR

2014-07-01

... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) PROTECTION OF STRATOSPHERIC OZONE Recycling... recycling rules promulgated pursuant to section 608 of the Clean Air Act Amendments of 1990) from small...

40 CFR Appendix C to Subpart F of... - Method for Testing Recovery Devices for Use With Small Appliances

Code of Federal Regulations, 2013 CFR

2013-07-01

... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) PROTECTION OF STRATOSPHERIC OZONE Recycling... recycling rules promulgated pursuant to section 608 of the Clean Air Act Amendments of 1990) from small...

40 CFR Appendix C to Subpart F of... - Method for Testing Recovery Devices for Use With Small Appliances

Code of Federal Regulations, 2012 CFR

2012-07-01

... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) PROTECTION OF STRATOSPHERIC OZONE Recycling... recycling rules promulgated pursuant to section 608 of the Clean Air Act Amendments of 1990) from small...

40 CFR Appendix C to Subpart F of... - Method for Testing Recovery Devices for Use With Small Appliances

Code of Federal Regulations, 2011 CFR

2011-07-01

... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) PROTECTION OF STRATOSPHERIC OZONE Recycling... recycling rules promulgated pursuant to section 608 of the Clean Air Act Amendments of 1990) from small...

Upscaling the pollutant emission from mixed recycled aggregates under compaction for civil applications.

PubMed

Galvín, Adela P; Ayuso, Jesús; Barbudo, Auxi; Cabrera, Manuel; López-Uceda, Antonio; Rosales, Julia

2017-12-27

In general terms, plant managers of sites producing construction wastes assess materials according to concise, legally recommended leaching tests that do not consider the compaction stage of the materials when they are applied on-site. Thus, the tests do not account for the real on-site physical conditions of the recycled aggregates used in civil works (e.g., roads or embankments). This leads to errors in estimating the pollutant potential of these materials. For that reason, in the present research, an experimental procedure is designed as a leaching test for construction materials under compaction. The aim of this laboratory test (designed specifically for the granular materials used in civil engineering infrastructures) is to evaluate the release of pollutant elements when the recycled aggregate is tested at its commercial grain-size distribution and when the material is compacted under on-site conditions. Two recycled aggregates with different gypsum contents (0.95 and 2.57%) were used in this study. In addition to the designed leaching laboratory test, the conventional compliance leaching test and the Dutch percolation test were performed. The results of the new leaching method were compared with the conventional leaching test results. After analysis, the chromium and sulphate levels obtained from the newly designed test were lower than those obtained from the conventional leaching test, and these were considered more seriously pollutant elements. This result confirms that when the leaching behaviour is evaluated for construction aggregates without density alteration, crushing the aggregate and using only the finest fraction, as is done in the conventional test (which is an unrealistic situation for aggregates that are applied under on-site conditions), the leaching behaviour is not accurately assessed.

LOFT. Mobile test building (TAN624) is recycled from ANP program ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

LOFT. Mobile test building (TAN-624) is recycled from ANP program for placement before LOFT containment building door. It has not yet been connected to containment building. Note borated water tank at right of dome. Narrow, vertical structure at right of door is shroud is shroud for air exhaust duct. Filter vaults lie between duct shroud and stack. Camera facing westerly. Date: 1974. INEEL negative no. 74-1072 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

Solving a product safety problem using a recycled high density polyethylene container

NASA Technical Reports Server (NTRS)

Liu, Ping; Waskom, T. L.

1993-01-01

The objectives are to introduce basic problem-solving techniques for product safety including problem identification, definition, solution criteria, test process and design, and data analysis. The students are given a recycled milk jug made of high density polyethylene (HDPE) by blow molding. The objectives are to design and perform proper material test(s) so they can evaluate the product safety if the milk jug is used in a certain way which is specified in the description of the procedure for this investigation.

Cryo-comminution of plastic waste.

PubMed

Gente, Vincenzo; La Marca, Floriana; Lucci, Federica; Massacci, Paolo; Pani, Eleonora

2004-01-01

Recycling of plastics is a big issue in terms of environmental sustainability and of waste management. The development of proper technologies for plastic recycling is recognised as a priority. To achieve this aim, the technologies applied in mineral processing can be adapted to recycling systems. In particular, the improvement of comminution technologies is one of the main actions to improve the quality of recycled plastics. The aim of this work is to point out suitable comminution processes for different types of plastic waste. Laboratory comminution tests have been carried out under different conditions of temperature and sample pre-conditioning adopting as refrigerant agents CO2 and liquid nitrogen. The temperature has been monitored by thermocouples placed in the milling chamber. Also different internal mill screens have been adopted. A proper procedure has been set up in order to obtain a selective comminution and a size reduction suitable for further separation treatment. Tests have been performed on plastics coming from medical plastic waste and from a plant for spent lead batteries recycling. Results coming from different mill devices have been compared taking into consideration different indexes for representative size distributions. The results of the performed tests show as cryo-comminution improves the effectiveness of size reduction of plastics, promotes liberation of constituents and increases specific surface size of comminuted particles in comparison to a comminution process carried out at room temperature. Copyright 2004 Elsevier Ltd.

The Rejuvenating Effect in Hot Asphalt Recycling by Mortar Transfer Ratio and Image Analysis.

PubMed

Wang, Fusong; Wang, Zipeng; Li, Chao; Xiao, Yue; Wu, Shaopeng; Pan, Pan

2017-05-24

Using a rejuvenator to improve the performance of asphalt pavement is an effective and economic way of hot asphalt recycling. This research analyzes the rejuvenating effect on aged asphalt by means of a Mortar Transfer Ratio (MTR) test, which concerns the ratio of asphalt mortar that moves from recycled aggregates (RAP aggregates) to fresh added aggregates when aged asphalt is treated with a regenerating agent and comes into contact with fresh aggregates. The proposed MTR test analyzes the regeneration in terms of the softening degree on aged asphalt when the rejuvenator is applied. The covered area ratio is studied with an image analyzing tool to understand the possibility of mortar transferring from RAP aggregates to fresh aggregates. Additionally, a micro-crack closure test is conducted and observed through a microscope. The repairing ability and diffusion characteristics of micro-cracks can therefore be analyzed. The test results demonstrate that the proposed mortar transfer ratio is a feasible way to evaluate rejuvenator diffusion during hot recycling. The mortar transfer ratio and uncovered area ratio on fresh aggregates are compatible, and can be used to quantify the contribution of the rejuvenator. Within a certain temperature range, the diffusing effect of the rejuvenator is better when the diffusing temperature is higher. The diffusion time of the rejuvenator is optimum when diffusion occurs for 4-8 h. When the rejuvenator is properly applied, the rough and cracking surface can be repaired, resulting in better covered aggregates. The micro-closure analysis visually indicates that rejuvenators can be used to repair the RAP aggregates during hot recycling.

The Rejuvenating Effect in Hot Asphalt Recycling by Mortar Transfer Ratio and Image Analysis

PubMed Central

Wang, Fusong; Wang, Zipeng; Li, Chao; Xiao, Yue; Wu, Shaopeng; Pan, Pan

2017-01-01

Using a rejuvenator to improve the performance of asphalt pavement is an effective and economic way of hot asphalt recycling. This research analyzes the rejuvenating effect on aged asphalt by means of a Mortar Transfer Ratio (MTR) test, which concerns the ratio of asphalt mortar that moves from recycled aggregates (RAP aggregates) to fresh added aggregates when aged asphalt is treated with a regenerating agent and comes into contact with fresh aggregates. The proposed MTR test analyzes the regeneration in terms of the softening degree on aged asphalt when the rejuvenator is applied. The covered area ratio is studied with an image analyzing tool to understand the possibility of mortar transferring from RAP aggregates to fresh aggregates. Additionally, a micro-crack closure test is conducted and observed through a microscope. The repairing ability and diffusion characteristics of micro-cracks can therefore be analyzed. The test results demonstrate that the proposed mortar transfer ratio is a feasible way to evaluate rejuvenator diffusion during hot recycling. The mortar transfer ratio and uncovered area ratio on fresh aggregates are compatible, and can be used to quantify the contribution of the rejuvenator. Within a certain temperature range, the diffusing effect of the rejuvenator is better when the diffusing temperature is higher. The diffusion time of the rejuvenator is optimum when diffusion occurs for 4–8 h. When the rejuvenator is properly applied, the rough and cracking surface can be repaired, resulting in better covered aggregates. The micro-closure analysis visually indicates that rejuvenators can be used to repair the RAP aggregates during hot recycling. PMID:28772935

Physical properties of recycled PET non-woven fabrics for buildings

NASA Astrophysics Data System (ADS)

Üstün Çetin, S.; Tayyar, A. E.

2017-10-01

Recycled fibers have been commonly used in non-woven production technology for engineering applications such as textile engineering and civil engineering. Nonwovens including recycled fibers can be utilized in insulation, roofing and floor separation applications. In this study, physical performance properties such as drape, bending resistance, tensile strength, and breaking elongation values of non-woven fabrics consisting of v-PET (virgin) and r-PET (recycled) fibers in five different blend ratios are examined comparatively. The test results indicated that r-PET can be used in non-wovens for civil engineering applications such as insulation, roofing and floor separation fulfilling the acceptable quality level values.

Analysis of Shear Bond Strength and Morphology of Er:YAG Laser-Recycled Ceramic Orthodontic Brackets

PubMed Central

Han, Ruo-qiao; Ji, Ling-fei; Ling, Chen

2016-01-01

Objective. The aim of this study was to compare the recycling of deboned ceramic brackets via an Er:YAG laser or via the traditional chairside processing methods of flaming and sandblasting; shear bond strength and morphological changes were evaluated in recycled brackets versus new brackets. Materials and Methods. 3M Clarity Self-Ligating Ceramic Brackets with a microcrystalline base were divided into groups subjected to flaming, sandblasting, or exposure to an Er:YAG laser. New ceramic brackets served as a control group. Shear bond strengths were determined with an Electroforce test machine and tested for statistical significance through analysis of variance. Morphological examinations of the recycled ceramic bracket bases were conducted with scanning electron microscopy and confocal laser scanning microscopy. Residue on the bracket base was analyzed with Raman spectroscopy. Results. Faded, dark adhesive was left on recycled bracket bases processed via flaming. Adhesive was thoroughly removed by both sandblasting and exposure to an Er:YAG laser. Compared with new brackets, shear bond strength was lower after sandblasting (p < 0.05), but not after exposure to an Er:YAG laser. The Er:YAG laser caused no damage to the bracket. Conclusion. Er:YAG lasers effectively remove adhesive from the bases of ceramic brackets without damaging them; thus, this method may be preferred over other recycling methods. PMID:27047964

Development of Low Cost Soil Stabilization Using Recycled Material

NASA Astrophysics Data System (ADS)

Ahmad, F.; Yahaya, A. S.; Safari, A.

2016-07-01

Recycled tyres have been used in many geotechnical engineering projects such as soil improvement, soil erosion and slope stability. Recycled tyres mainly in chip and shredded form are highly compressible under low and normal pressures. This characteristic would cause challenging problems in some applications of soil stabilization such as retaining wall and river bank projects. For high tensile stress and low tensile strain the use of fiberglass would be a good alternative for recycled tyre in some cases. To evaluate fiberglass as an alternative for recycled tyre, this paper focused on tests of tensile tests which have been carried out between fiberglass and recycled tyre strips. Fibreglass samples were produced from chopped strand fibre mat, a very low-cost type of fibreglass, which is cured by resin and hardener. Fibreglass samples in the thickness of 1 mm, 2 mm, 3 mm and 4 mm were developed 100 mm x 300 mm pieces. It was found that 3 mm fibreglass exhibited the maximum tensile load (MTL) and maximum tensile stress (MTS) greater than other samples. Statistical analysis on 3 mm fibreglass indicated that in the approximately equal MTL fibreglass samples experienced 2% while tyre samples experienced 33.9% ultimate tensile strain (UTST) respectively. The results also showed an approximately linear relationship between stress and strain for fibreglass samples and Young's modulus (E), ranging from 3581 MPa to 4728 MPa.

Long-term performance of a hot in-place recycling project final report.

DOT National Transportation Integrated Search

2016-08-01

This report documents the construction and long-term performance of a hot in-place recycled (HIPR) : project on SR 542. HIPR project selection, mix design, construction and testing are described. It was shown that : the HIPR process successfully reha...

Quality Assessment of Mixed and Ceramic Recycled Aggregates from Construction and Demolition Wastes in the Concrete Manufacture According to the Spanish Standard †

PubMed Central

Rodríguez-Robles, Desirée; García-González, Julia; Juan-Valdés, Andrés; Pozo, Julia Mª Morán-del; Guerra-Romero, Manuel I

2014-01-01

Construction and demolition waste (CDW) constitutes an increasingly significant problem in society due to the volume generated, rendering sustainable management and disposal problematic. The aim of this study is to identify a possible reuse option in the concrete manufacturing for recycled aggregates with a significant ceramic content: mixed recycled aggregates (MixRA) and ceramic recycled aggregates (CerRA). In order to do so, several tests are conducted in accordance with the Spanish Code on Structural Concrete (EHE-08) to determine the composition in weight and physic-mechanical characteristics (particle size distributions, fine content, sand equivalent, density, water absorption, flakiness index, and resistance to fragmentation) of the samples for the partial inclusion of the recycled aggregates in concrete mixes. The results of these tests clearly support the hypothesis that this type of material may be suitable for such partial replacements if simple pretreatment is carried out. Furthermore, this measure of reuse is in line with European, national, and regional policies on sustainable development, and presents a solution to the environmental problem caused by the generation of CDW. PMID:28788164

Influence of Rapid Freeze-Thaw Cycling on the Mechanical Properties of Sustainable Strain-Hardening Cement Composite (2SHCC)

PubMed Central

Jang, Seok-Joon; Rokugo, Keitetsu; Park, Wan-Shin; Yun, Hyun-Do

2014-01-01

This paper provides experimental results to investigate the mechanical properties of sustainable strain-hardening cement composite (2SHCC) for infrastructures after freeze-thaw actions. To improve the sustainability of SHCC materials in this study, high energy-consumptive components—silica sand, cement, and polyvinyl alcohol (PVA) fibers—in the conventional SHCC materials are partially replaced with recycled materials such as recycled sand, fly ash, and polyethylene terephthalate (PET) fibers, respectively. To investigate the mechanical properties of green SHCC that contains recycled materials, the cement, PVA fiber and silica sand were replaced with 10% fly ash, 25% PET fiber, and 10% recycled aggregate based on preliminary experimental results for the development of 2SHCC material, respectively. The dynamic modulus of elasticity and weight for 2SHCC material were measured at every 30 cycles of freeze-thaw. The effects of freeze-thaw cycles on the mechanical properties of sustainable SHCC are evaluated by conducting compressive tests, four-point flexural tests, direct tensile tests and prism splitting tests after 90, 180, and 300 cycles of rapid freeze-thaw. Freeze-thaw testing was conducted according to ASTM C 666 Procedure A. Test results show that after 300 cycles of freezing and thawing actions, the dynamic modulus of elasticity and mass loss of damaged 2SHCC were similar to those of virgin 2SHCC, while the freeze-thaw cycles influence mechanical properties of the 2SHCC material except for compressive behavior. PMID:28788522

Properties of concrete blocks prepared with low grade recycled aggregates.

PubMed

Poon, Chi-Sun; Kou, Shi-cong; Wan, Hui-wen; Etxeberria, Miren

2009-08-01

Low grade recycled aggregates obtained from a construction waste sorting facility were tested to assess the feasibility of using these in the production of concrete blocks. The characteristics of the sorted construction waste are significantly different from that of crushed concrete rubbles that are mostly derived from demolition waste streams. This is due to the presence of higher percentages of non-concrete components (e.g. >10% soil, brick, tiles etc.) in the sorted construction waste. In the study reported in this paper, three series of concrete block mixtures were prepared by using the low grade recycled aggregates to replace (i) natural coarse granite (10mm), and (ii) 0, 25, 50, 75 and 100% replacement levels of crushed stone fine (crushed natural granite <5mm) in the concrete blocks. Test results on properties such as density, compressive strength, transverse strength and drying shrinkage as well as strength reduction after exposure to 800 degrees C are presented below. The results show that the soil content in the recycled fine aggregate was an important factor in affecting the properties of the blocks produced and the mechanical strength deceased with increasing low grade recycled fine aggregate content. But the higher soil content in the recycled aggregates reduced the reduction of compressive strength of the blocks after exposure to high temperature due probably to the formation of a new crystalline phase. The results show that the low grade recycled aggregates obtained from the construction waste sorting facility has potential to be used as aggregates for making non-structural pre-cast concrete blocks.

PLA coated paper containing active inorganic nanoparticles: Material characterization and fate of nanoparticles in the paper recycling process.

PubMed

Zhang, Hai; Bussini, Daniele; Hortal, Mercedes; Elegir, Graziano; Mendes, Joana; Jordá Beneyto, Maria

2016-06-01

For paper and paperboard packaging, recyclability plays an important role in conserving the resources and reducing the environmental impacts. Therefore, when it comes to the nano-enabled paper packaging material, the recyclability issue should be properly addressed. This study represents our first report on the fate of nanomaterials in paper recycling process. The packaging material of concern is a PLA (Polylactic Acid) coated paper incorporating zinc oxide nanoparticles in the coating layer. The material was characterised and assessed in a lab-scale paper recycling line. The recyclability test was based on a method adapted from ATICELCA MC501-13, which enabled to recover over 99% of the solids material. The mass balance result indicates that 86-91% zinc oxide nanoparticles ended up in the rejected material stream, mostly embedded within the polymer coating; whereas 7-16% nanoparticles ended up in the accepted material stream. Besides, the tensile strength of the recycled handsheets suggests that the nano-enabled coating had no negative impacts on the recovered fibre quality. Copyright © 2016 Elsevier Ltd. All rights reserved.

Innovative Chemical Process for Recycling Thermosets Cured with Recyclamines® by Converting Bio-Epoxy Composites in Reusable Thermoplastic—An LCA Study

PubMed Central

Banatao, Diosdado R.; Pastine, Stefan J.

2018-01-01

An innovative recycling process for thermoset polymer composites developed by Connora Technologies (Hayward, CA, USA) was studied. The process efficacy has already been tested, and it is currently working at the plant level. The main aspect investigated in the present paper was the environmental impact by means of the Life Cycle Assessment (LCA) method. Because of the need to recycle and recover materials at their end of life, the Connora process creates a great innovation in the market of epoxy composites, as they are notoriously not recyclable. Connora Technologies developed a relatively gentle chemical recycling process that induces the conversion of thermosets into thermoplastics. The LCA demonstrated that low environmental burdens are associated with the process itself and, furthermore, impacts are avoided due to the recovery of the epoxy-composite constituents (fibres and matrix). A carbon fibre (CF) epoxy-composite panel was produced through Vacuum Resin Transfer Moulding (VRTM) and afterwards treated using the Connora recycling process. The LCA results of both the production and the recycling phases are reported. PMID:29495571

Effect of Er:YAG Laser and Sandblasting in Recycling of Ceramic Brackets.

PubMed

Yassaei, Soghra; Aghili, Hossein; Hosseinzadeh Firouzabadi, Azadeh; Meshkani, Hamidreza

2017-01-01

Introduction: This study was performed to determine the shear bond strength of rebonded mechanically retentive ceramic brackets after recycling with Erbium-Doped Yttrium Aluminum Garnet (Er:YAG) laser or sandblasting. Methods: Twenty-eight debonded ceramic brackets plus 14 intact new ceramic brackets were used in this study. Debonded brackets were randomly divided into 2 groups of 14. One group was treated by Er:YAG laser and the other with sandblasting. All the specimens were randomly bonded to 42 intact human upper premolars. The shear bond strength of all specimens was determined with a universal testing machine at a crosshead speed of 0.5 mm/min until bond failure occurred. The recycled bracket base surfaces were observed under a scanning electron microscope (SEM). Analysis of variance (ANOVA) and Tukey tests were used to compare the shear bond strength of the 3 groups. Fisher exact test was used to evaluate the differences in adhesive remnant index (ARI) scores. Results: The highest bond strength belonged to brackets recycled by Sandblasting (16.83 MPa). There was no significant difference between the shear bond strength of laser and control groups. SEM photographs showed differences in 2 recycling methods. The laser recycled bracket appeared to have as well-cleaned base as the new bracket. Although the sandblasted bracket photographs showed no remnant adhesives, remarkable micro-roughening of the base of the bracket was apparent. Conclusion: According to the results of this study, both Er:YAG laser and sandblasting were efficient to mechanically recondition retentive ceramic brackets. Also, Er:YAG laser did not change the design of bracket base while removing the remnant adhesives which might encourage its application in clinical practice.

Effect of Er:YAG Laser and Sandblasting in Recycling of Ceramic Brackets

PubMed Central

Yassaei, Soghra; Aghili, Hossein; Hosseinzadeh Firouzabadi, Azadeh; Meshkani, Hamidreza

2017-01-01

Introduction: This study was performed to determine the shear bond strength of rebonded mechanically retentive ceramic brackets after recycling with Erbium-Doped Yttrium Aluminum Garnet (Er:YAG) laser or sandblasting. Methods: Twenty-eight debonded ceramic brackets plus 14 intact new ceramic brackets were used in this study. Debonded brackets were randomly divided into 2 groups of 14. One group was treated by Er:YAG laser and the other with sandblasting. All the specimens were randomly bonded to 42 intact human upper premolars. The shear bond strength of all specimens was determined with a universal testing machine at a crosshead speed of 0.5 mm/min until bond failure occurred. The recycled bracket base surfaces were observed under a scanning electron microscope (SEM). Analysis of variance (ANOVA) and Tukey tests were used to compare the shear bond strength of the 3 groups. Fisher exact test was used to evaluate the differences in adhesive remnant index (ARI) scores. Results: The highest bond strength belonged to brackets recycled by Sandblasting (16.83 MPa). There was no significant difference between the shear bond strength of laser and control groups. SEM photographs showed differences in 2 recycling methods. The laser recycled bracket appeared to have as well-cleaned base as the new bracket. Although the sandblasted bracket photographs showed no remnant adhesives, remarkable micro-roughening of the base of the bracket was apparent. Conclusion: According to the results of this study, both Er:YAG laser and sandblasting were efficient to mechanically recondition retentive ceramic brackets. Also, Er:YAG laser did not change the design of bracket base while removing the remnant adhesives which might encourage its application in clinical practice. PMID:28912939

Tracking the Key Constituents of Concern of the WTP LAW Stream

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mabrouki, Ridha B.; Matlack, Keith S.; Abramowitz, Howard

The testing results presented in the present report were also obtained on a DM10 melter system operated with the primary WTP LAW offgas system components with recycle, as specified in the statement of work (SOW) [6] and detailed in the Test Plan for this work [7]. The primary offgas system components include the SBS, the WESP, and a recycle system that allows recycle of liquid effluents back to the melter, as in the present baseline for the WTP LAW vitrification. The partitioning of technetium and other key constituents between the glass waste form, the offgas system liquid effluents, the offgasmore » stream that exits the WESP, and the liquid condensate from the vacuum evaporator were quantified in this work. The tests employed three different LAW streams spanning a range of waste compositions anticipated for WTP. Modifications to the offgas system and operational strategy were made to expedite the approach to steady state concentrations of key constituents in the glass and offgas effluent solutions during each test.« less

PFC Decontamination of a Metal Surface and the Recycling of a Spent PFC Solution

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jung, C.H.; Won, H.J.; Oh, W.Z.

2006-07-01

PFC (per-fluorocarbon) ultrasonic decontamination behavior of loosely contaminated metal specimens such as a plate, pipe, welding and a crevice specimen in a mixed solution of PFC and an anionic surfactant was investigated. Perfluoroheptane (C{sub 7}F{sub 16}) was used as a PFC ultrasonic media. The contaminants were completely removed for almost all of the tested specimens except for the longest pipe length specimen. For the 6-cm long specimen, 98.5 % of the contaminants were removed. For the recycling of the PFC solution, a distillation test for the spent PFC solution was also performed. The results show that 97.5 % of themore » PFC was recycled without a loss of the decontamination efficiency. (authors)« less

Demonstrate a Low Biochemical Oxygen Demand Aircraft Deicing Fluid

DTIC Science & Technology

2013-03-01

Technologies International, LTD for collection and recycling of fluids. Spent fluid, diluted with any water, slush or snow removed from the aircraft or...Resistance Unmated only – some failures Voltage Withstand Testing Unmated only – some failures Plastic Windows Crazing Effect Pass The testing did result...At Joint Base McGuire-Dix-Lakehurst, however, waste PG is currently collected with a vacuum truck and recycled . Factors such as the market demand

Demonstrate a Low Biochemical Oxygen Demand Aircraft Deicing Fluid

DTIC Science & Technology

2013-03-04

Technologies International, LTD for collection and recycling of fluids. Spent fluid, diluted with any water, slush or snow removed from the aircraft or...Resistance Unmated only – some failures Voltage Withstand Testing Unmated only – some failures Plastic Windows Crazing Effect Pass The testing did result...At Joint Base McGuire-Dix-Lakehurst, however, waste PG is currently collected with a vacuum truck and recycled . Factors such as the market demand

Feasibility and Economics Study of the Treatment, Recycling and Disposal of Spent Abrasives

DTIC Science & Technology

1999-04-09

compression, and film stripping. The recycling performance testing plan is summarized in Table 2. (The test plan is discussed in detail in Appendix B: Law...D1188 Yes Yes Immersion Compression ................... ASTM C4867 Yes Yes Film Stripping................................... CalTrans 302 Yes Yes...from 10% to 20% for aluminum oxide abrasives, and 15% to 30% for garnet abrasives. 9 Data Intepretation SSPC-AB 1 requires that the conductivitiy of

Cryopolymers

NASA Technical Reports Server (NTRS)

1995-01-01

NASA's Technology Transfer Office (TTO) at Stennis Space Center worked with a small tire recycling company, Cryopolymers, Inc. in St. Francisville, La., to improve its process for recycling used tires. Stennis helped Cryopolymers make better use of the cryogens, or super-cold fluids, used in its recycling process. First, the tires are frozen, then broken down and made into a material called 'crumb,' which can be used in asphalt road beds, agricultural hoses, and truck bed liners. TTO based this assistance on NASA's experience using cryogens in the testing of Space Shuttle Main Engines.

Poly-paper: a sustainable material for packaging, based on recycled paper and recyclable with paper.

PubMed

Del Curto, Barbara; Barelli, Nadia; Profaizer, Mauro; Farè, Silvia; Tanzi, Maria Cristina; Cigada, Alberto; Ognibene, Giulia; Recca, Giuseppe; Cicala, Gianluca

2016-11-02

Until now, environmental sustainability issues are almost entirely unsolved for packaging materials. With the final aim of finding materials with a single recycling channel, cellulose fiber/poly(vinyl)alcohol composites were investigated. After extrusion and injection molding, samples of composite with different cellulose fiber content (30%, 50% and 70% w/w) were tested. Tensile mechanical tests exhibited an improvement in composite stiffness when the reinforcement content was increased together with a decrease in composite elongation. Solubility tests performed at room temperature and 45°C showed different behavior depending on the water-resistant film applied on the composite (50% cellulose fiber content). In particular, the uncoated composite showed complete solubility after 2 hours, whereas at the same time point, no solubility occurred when a non-water-soluble varnish was used. The proposed composites, named Poly-paper, appear to warrant further investigation as highly sustainable packaging.

Seismic performance of recycled concrete-filled square steel tube columns

NASA Astrophysics Data System (ADS)

Chen, Zongping; Jing, Chenggui; Xu, Jinjun; Zhang, Xianggang

2017-01-01

An experimental study on the seismic performance of recycled concrete-filled square steel tube (RCFST) columns is carried out. Six specimens were designed and tested under constant axial compression and cyclic lateral loading. Two parameters, replacement percentage of recycled coarse aggregate (RCA) and axial compression level, were considered in the test. Based on the experimental data, the hysteretic loops, skeleton curves, ductility, energy dissipation capacity and stiffness degradation of RCFST columns were analyzed. The test results indicate that the failure modes of RCFST columns are the local buckling of the steel tube at the bottom of the columns, and the hysteretic loops are full and their shapes are similar to normal CFST columns. Furthermore, the ductility coefficient of all specimens are close to 3.0, and the equivalent viscous damping coefficient corresponding to the ultimate lateral load ranges from 0.323 to 0.360, which demonstrates that RCFST columns exhibit remarkable seismic performance.

A long-term study on the effect of magnetite supplementation in continuous anaerobic digestion of dairy effluent - Magnetic separation and recycling of magnetite.

PubMed

Baek, Gahyun; Jung, Heejung; Kim, Jaai; Lee, Changsoo

2017-10-01

Promotion of direct interspecies electron transfer (DIET) between exoelectrogenic bacteria and electron-utilizing methanogens has recently been discussed as a new method for enhanced biomethanation. This study evaluated the effect of magnetite-promoted DIET in continuous anaerobic digestion of dairy effluent and tested the magnetic separation and recycling of magnetite to avoid continuous magnetite addition. The applied magnetite recycling method effectively supported enhanced DIET activity and biomethanation performance over a long period (>250days) without adding extra magnetite. DIET via magnetite particles as electrical conduits was likely the main mechanism for the enhanced biomethanation. Magnetite formed complex aggregate structures with microbes, and magnetite recycling also helped retain more biomass in the process. Methanosaeta was likely the major methanogen group responsible for DIET-based methanogenesis, in association with Proteobacteria and Chloroflexi populations as syntrophic partners. The recycling approach proved robust and effective, highlighting the potential of magnetite recycling for high-rate biomethanation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Recycling the liquid fraction of alkaline hydrogen peroxide in the pretreatment of corn stover.

PubMed

Alencar, Bárbara Ribeiro Alves; Reis, Alexandre Libanio Silva; de Souza, Raquel de Fatima Rodrigues; Morais, Marcos Antônio; Menezes, Rômulo Simões Cezar; Dutra, Emmanuel Damilano

2017-10-01

The aim of this study was to evaluate the influence of recycling the liquid fraction of pretreatment with alkaline hydrogen peroxide (AHP) on the hydrolysis of corn stover. Corn stover was pretreated in the traditional condition with 7.5% v/v H 2 O 2 . After pretreatment, the solids were separated from the liquid fraction and five successive reuse cycles of the liquid fraction were tested. The solid fraction from pretreatment in each recycle was submitted to enzymatic hydrolysis. The number of recycles had a linear negative effect (R 2 =0.98) on biomass delignification efficiency and also affected negatively the enzymatic conversion efficiency. Despite the decrease in efficiency after each recycling step, reuse of the liquid fraction leads to reduction in water, H 2 O 2 and NaOH consumption of up to 57.6%, 59.6% and 57.6%, respectively. These findings point to an efficient recycling technology, which may reduce costs and save water. Copyright © 2017 Elsevier Ltd. All rights reserved.

Incorporation of gypsum waste in ceramic block production: Proposal for a minimal battery of tests to evaluate technical and environmental viability of this recycling process.

PubMed

Godinho-Castro, Alcione P; Testolin, Renan C; Janke, Leandro; Corrêa, Albertina X R; Radetski, Claudemir M

2012-01-01

Civil engineering-related construction and demolition debris is an important source of waste disposed of in municipal solid waste landfills. After clay materials, gypsum waste is the second largest contributor to the residential construction waste stream. As demand for sustainable building practices grows, interest in recovering gypsum waste from construction and demolition debris is increasing, but there is a lack of standardized tests to evaluate the technical and environmental viability of this solid waste recycling process. By recycling gypsum waste, natural deposits of gypsum might be conserved and high amounts of the waste by-product could be reused in the civil construction industry. In this context, this paper investigates a physical property (i.e., resistance to axial compression), the chemical composition and the ecotoxicological potential of ceramic blocks constructed with different proportions of clay, cement and gypsum waste, and assesses the feasibility of using a minimal battery of tests to evaluate the viability of this recycling process. Consideration of the results for the resistance to axial compression tests together with production costs revealed that the best formulation was 35% of plastic clay, 35% of non-plastic clay, 10% of Portland cement and 20% of gypsum waste, which showed a mean resistance of 4.64MPa. Energy dispersive X-ray spectrometry showed calcium and sulfur to be the main elements, while quartz, gypsum, ettringite and nacrite were the main crystalline compounds found in this formulation. Ecotoxicity tests showed that leachate from this formulation is weakly toxic toward daphnids and bacteria (EC(20%)=69.0 and 75.0, respectively), while for algae and fish the leachate samples were not toxic at the EC(50%) level. Overall, these results show that the addition of 20% of gypsum waste to the ceramic blocks could provide a viable substitute for clay in the ceramics industry and the tests applied in this study proved to be a useful tool for the technical and environmental evaluation of this recycling process, bacterial and daphnid tests being more sensitive than algae and fish tests. Copyright © 2011 Elsevier Ltd. All rights reserved.

Evaluation of field-produced hot mix asphalt (HMA) mixtures with fractionated recycled asphalt pavement (RAP) : 2007 Illinois tollway field mix trials.

DOT National Transportation Integrated Search

2008-10-01

To test the fractionated recycled asphalt pavement (FRAP) materials, the Illinois Tollway, working through its : contractors and consultants, developed and conducted a project on the applicability and feasibility of using : increased RAP contents thr...

Characterization of Formaldehyde Emissions from Tire Crumb Rubber in Small Environmental Chambers - 2

EPA Science Inventory

Concerns have been raised about the safety of recycled rubber tire crumbs used in synthetic turf fields and playgrounds in the United States. To support federal efforts to better characterize recycled tire-derived surface materials, dynamic small chamber tests were conducted at...

Childhood Lead Exposure from Battery Recycling in Vietnam

PubMed Central

Van Tung, Lo; Wallace, Ryan M.; Havens, Deborah J.; Karr, Catherine J.; Bich Diep, Nguyen; Croteau, Gerry A.; Beaudet, Nancy J.; Duy Bao, Nguyen

2015-01-01

Background. Battery recycling facilities in developing countries can cause community lead exposure. Objective. To evaluate child lead exposure in a Vietnam battery recycling craft village after efforts to shift home-based recycling outside the village. Methods. This cross-sectional study evaluated 109 children in Dong Mai village, using blood lead level (BLL) measurement, parent interview, and household observation. Blood samples were analyzed with a LeadCare II field instrument; highest BLLs (≥45 μg/dL) were retested by laboratory analysis. Surface and soil lead were measured at 11 households and a school with X-ray fluorescence analyzer. Results. All children had high BLLs; 28% had BLL ≥45 μg/dL. Younger age, family recycling, and outside brick surfaces were associated with higher BLL. Surface and soil lead levels were high at all tested homes, even with no recycling history. Laboratory BLLs were lower than LeadCare BLLs, in 24 retested children. Discussion. In spite of improvements, lead exposure was still substantial and probably associated with continued home-based recycling, legacy contamination, and workplace take-home exposure pathways. There is a need for effective strategies to manage lead exposure from battery recycling in craft villages. These reported BLL values should be interpreted cautiously, although the observed field-laboratory discordance may reflect bias in laboratory results. PMID:26587532

Childhood Lead Exposure from Battery Recycling in Vietnam.

PubMed

Daniell, William E; Van Tung, Lo; Wallace, Ryan M; Havens, Deborah J; Karr, Catherine J; Bich Diep, Nguyen; Croteau, Gerry A; Beaudet, Nancy J; Duy Bao, Nguyen

2015-01-01

Battery recycling facilities in developing countries can cause community lead exposure. To evaluate child lead exposure in a Vietnam battery recycling craft village after efforts to shift home-based recycling outside the village. This cross-sectional study evaluated 109 children in Dong Mai village, using blood lead level (BLL) measurement, parent interview, and household observation. Blood samples were analyzed with a LeadCare II field instrument; highest BLLs (≥45 μg/dL) were retested by laboratory analysis. Surface and soil lead were measured at 11 households and a school with X-ray fluorescence analyzer. All children had high BLLs; 28% had BLL ≥45 μg/dL. Younger age, family recycling, and outside brick surfaces were associated with higher BLL. Surface and soil lead levels were high at all tested homes, even with no recycling history. Laboratory BLLs were lower than LeadCare BLLs, in 24 retested children. In spite of improvements, lead exposure was still substantial and probably associated with continued home-based recycling, legacy contamination, and workplace take-home exposure pathways. There is a need for effective strategies to manage lead exposure from battery recycling in craft villages. These reported BLL values should be interpreted cautiously, although the observed field-laboratory discordance may reflect bias in laboratory results.

Field test results for nitrogen removal by the constructed wetland component of an agricultural water recycling system

USDA-ARS?s Scientific Manuscript database

Wetland Reservoir Subirrigation Systems (WRSIS) are innovative agricultural water recycling systems that can provide economic and environmental benefits. A constructed wetland is a main component of WRSIS, and an important function of this constructed wetland is drainage water treatment of nitrog...

Recyclability of PET/WPI/PE Multilayer Films by Removal of Whey Protein Isolate-Based Coatings with Enzymatic Detergents.

PubMed

Cinelli, Patrizia; Schmid, Markus; Bugnicourt, Elodie; Coltelli, Maria Beatrice; Lazzeri, Andrea

2016-06-14

Multilayer plastic films provide a range of properties, which cannot be obtained from monolayer films but, at present, their recyclability is an open issue and should be improved. Research to date has shown the possibility of using whey protein as a layer material with the property of acting as an excellent barrier against oxygen and moisture, replacing petrochemical non-recyclable materials. The innovative approach of the present research was to achieve the recyclability of the substrate films by separating them, with a simple process compatible with industrial procedures, in order to promote recycling processes leading to obtain high value products that will beneficially impact the packaging and food industries. Hence, polyethyleneterephthalate (PET)/polyethylene (PE) multi-layer film was prepared based on PET coated with a whey protein layer, and then the previous structure was laminated with PE. Whey proteins, constituting the coating, can be degraded by enzymes so that the coating films can be washed off from the plastic substrate layer. Enzyme types, dosage, time, and temperature optima, which are compatible with procedures adopted in industrial waste recycling, were determined for a highly-efficient process. The washing of samples based on PET/whey and PET/whey/PE were efficient when performed with enzymatic detergent containing protease enzymes, as an alternative to conventional detergents used in recycling facilities. Different types of enzymatic detergents tested presented positive results in removing the protein layer from the PET substrate and from the PET/whey/PE multilayer films at room temperature. These results attested to the possibility of organizing the pre-treatment of the whey-based multilayer film by washing with different available commercial enzymatic detergents in order to separate PET and PE, thus allowing a better recycling of the two different polymers. Mechanical properties of the plastic substrate, such as stress at yield, stress and elongation at break, evaluated by tensile testing on films before and after cleaning, were are not significantly affected by washing with enzymatic detergents.

Properties of Concrete Paving Blocks and Hollow Tiles with Recycled Aggregate from Construction and Demolition Wastes.

PubMed

Rodríguez, Carlos; Miñano, Isabel; Aguilar, Miguel Ángel; Ortega, José Marcos; Parra, Carlos; Sánchez, Isidro

2017-11-30

In recent years there has been an increasing tendency to recycle the wastes generated by building companies in the construction industry, demolition wastes being the most important in terms of volume. The aim of this work is to study the possibility of using recycled aggregates from construction and demolition wastes in the preparation of precast non-structural concretes. To that purpose, two different percentages (15% and 30%) of natural aggregates were substituted by recycled aggregates in the manufacture of paving blocks and hollow tiles. Dosages used by the company have not been changed by the introduction of recycled aggregate. Precast elements have been tested by means of compressive and flexural strength, water absorption, density, abrasion, and slipping resistance. The results obtained show the possibility of using these wastes at an industrial scale, satisfying the requirements of the Spanish standards for these elements.

Properties of Concrete Paving Blocks and Hollow Tiles with Recycled Aggregate from Construction and Demolition Wastes

PubMed Central

Rodríguez, Carlos; Miñano, Isabel; Aguilar, Miguel Ángel; Parra, Carlos

2017-01-01

In recent years there has been an increasing tendency to recycle the wastes generated by building companies in the construction industry, demolition wastes being the most important in terms of volume. The aim of this work is to study the possibility of using recycled aggregates from construction and demolition wastes in the preparation of precast non-structural concretes. To that purpose, two different percentages (15% and 30%) of natural aggregates were substituted by recycled aggregates in the manufacture of paving blocks and hollow tiles. Dosages used by the company have not been changed by the introduction of recycled aggregate. Precast elements have been tested by means of compressive and flexural strength, water absorption, density, abrasion, and slipping resistance. The results obtained show the possibility of using these wastes at an industrial scale, satisfying the requirements of the Spanish standards for these elements. PMID:29189745

Joint investigation of working conditions, environmental and system performance at recycling centres--development of instruments and their usage.

PubMed

Engkvist, I-L; Eklund, J; Krook, J; Björkman, M; Sundin, E; Svensson, R; Eklund, M

2010-05-01

Recycling is a new and developing industry, which has only been researched to a limited extent. This article describes the development and use of instruments for data collection within a multidisciplinary research programme "Recycling centres in Sweden - working conditions, environmental and system performance". The overall purpose of the programme was to form a basis for improving the function of recycling centres with respect to these three perspectives and the disciplines of: ergonomics, safety, external environment, and production systems. A total of 10 instruments were developed for collecting data from employees, managers and visitors at recycling centres, including one instrument for observing visitors. Validation tests were performed in several steps. This, along with the quality of the collected data, and experience from the data collection, showed that the instruments and methodology used were valid and suitable for their purpose. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

Analyzing the success of the volume-based waste fee system in South Korea.

PubMed

Park, Seejeen; Lah, T J

2015-09-01

For more than a decade, South Korea has been ranked first among the OECD (Organization for Economic Cooperation and Development) members in their municipal solid waste (MSW) recycling rate. One of the major contributing factors for its outstanding MSW recycling performance is the volume-based waste fee (VWF) system implemented in 1995. Despite the perceived success of VWF, there has been few research conducted that has sought to demonstrate the success of the policy in an empirical manner. Research conducted currently on VWF in South Korea tends to have limitations in empirical approaches and identifying the intervention effect of VWF on recycling performance. This study attempts to empirically test whether the adoption of VWF positively affected recycling performance in Korea over time. The findings suggest that although there was a dramatic increase of the recycling rate with the introduction of VWF in 1995, Korea's MSW recycling performance settled back again and showed the constant pace after the intervention. No significant differences in recycling rate were found between before and after 1995 period. In conclusion, implications and suggestions for both research and practice are proposed. Copyright © 2015 Elsevier Ltd. All rights reserved.

Phosphorus and nitrogen recycle following algal bio-crude production via continuous hydrothermal liquefaction

DOE PAGES

Edmundson, S.; Huesemann, M.; Kruk, R.; ...

2017-07-25

Phosphorus and nitrogen are essential components of microalgal growth media. Critical to a wide range of biochemical processes, they commonly limit primary productivity. Recycling elemental phosphorus and fixed nitrogen after fuel conversion via hydrothermal liquefaction (HTL) of algae biomass reduces the need for mined phosphorus and synthetic nitrogen resources. We used scenedesmus obliquus DOE 0152.Z and Chlorella sorokiniana DOE1412 as test organisms in assessing nutrient recycle of phosphorus from filtered solids collected downstream of the HTL reactor and nitrogen collected from the aqueous phase after gravimetric biocrude separation. Maximum specific growth rates were measured in growth media using HTL wastemore » as the sole source of either phosphorus or nitrogen and were compared to an algal growth medium control (BG-11). The maximum specific growth rate of both organisms in the recycled phosphorus medium were nearly identical to rates observed in the control medium. Both organisms showed significantly reduced growth rates in the recycled nitrogen medium. C. sorokiniana DOE1412 adapted after several days of exposure whereas S. obliquus DOE0152.Z exhibited poor adaptability to the recycled nitrogen medium. After adaptation, growth rates observed with C. sorokiniana DOE1412 in the recycled nitrogen medium were 3.02 (± 0.13) day -1, 89% of the control medium (3.40 ± 0.21). We further tested maximum specific growth rates of C. sorokiniana DOE1412 in a medium derived entirely from HTL byproducts, completely replacing all components including nitrogen and phosphorus. In this medium we observed rates of 2.70 ± 0.05 day -1, 79% of the control. By adding trace metals to this recycled medium we improved growth rates significantly to 3.10 ± 0.10, 91% of the control, which indicates a critical element is lost in the conversion process. Recycling elemental resources such as phosphorus and nitrogen from the HTL biofuel conversion process can provide a significant reduction in media cost and improves the prospects for industrial scale, algae-based biofuels.« less

Phosphorus and nitrogen recycle following algal bio-crude production via continuous hydrothermal liquefaction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Edmundson, S.; Huesemann, M.; Kruk, R.

Phosphorus and nitrogen are essential components of microalgal growth media. Critical to a wide range of biochemical processes, they commonly limit primary productivity. Recycling elemental phosphorus and fixed nitrogen after fuel conversion via hydrothermal liquefaction (HTL) of algae biomass reduces the need for mined phosphorus and synthetic nitrogen resources. We used scenedesmus obliquus DOE 0152.Z and Chlorella sorokiniana DOE1412 as test organisms in assessing nutrient recycle of phosphorus from filtered solids collected downstream of the HTL reactor and nitrogen collected from the aqueous phase after gravimetric biocrude separation. Maximum specific growth rates were measured in growth media using HTL wastemore » as the sole source of either phosphorus or nitrogen and were compared to an algal growth medium control (BG-11). The maximum specific growth rate of both organisms in the recycled phosphorus medium were nearly identical to rates observed in the control medium. Both organisms showed significantly reduced growth rates in the recycled nitrogen medium. C. sorokiniana DOE1412 adapted after several days of exposure whereas S. obliquus DOE0152.Z exhibited poor adaptability to the recycled nitrogen medium. After adaptation, growth rates observed with C. sorokiniana DOE1412 in the recycled nitrogen medium were 3.02 (± 0.13) day -1, 89% of the control medium (3.40 ± 0.21). We further tested maximum specific growth rates of C. sorokiniana DOE1412 in a medium derived entirely from HTL byproducts, completely replacing all components including nitrogen and phosphorus. In this medium we observed rates of 2.70 ± 0.05 day -1, 79% of the control. By adding trace metals to this recycled medium we improved growth rates significantly to 3.10 ± 0.10, 91% of the control, which indicates a critical element is lost in the conversion process. Recycling elemental resources such as phosphorus and nitrogen from the HTL biofuel conversion process can provide a significant reduction in media cost and improves the prospects for industrial scale, algae-based biofuels.« less

Chemical sensors for space applications

NASA Technical Reports Server (NTRS)

Bonting, Sjoerd L.

1992-01-01

The payload of the Space Station Freedom will include sensors for frequent monitoring of the water recycling process and for measuring the many biochemical parameters related to onboard experiments. This paper describes the sensor technologies and the types of transducers and selectors considered for these sensors. Particular attention is given to such aspects of monitoring of the water recycling process as the types of water use, the sources of water and their hazards, the sensor systems for monitoring, microbial monitoring, and monitoring toxic metals and organics. An approach for monitoring water recycling is suggested, which includes microbial testing with a potentiometric device (which should be in first line of tests), the use of an ion-selective electrode for inorganic ion determinations, and the use of optic fiber techniques for the determination of total organic carbon.

Compact, ultra-low vibration, closed-cycle helium recycler for uninterrupted operation of MEG with SQUID magnetometers

NASA Astrophysics Data System (ADS)

Wang, Chao; Sun, Limin; Lichtenwalter, Ben; Zerkle, Brent; Okada, Yoshio

2016-06-01

A closed-cycle helium recycler was developed for continuous uninterrupted operation for magnetometer-based whole-head magnetoencephalography (MEG) systems. The recycler consists of a two stage 4 K pulse-tube cryocooler and is mounted on the roof of a magnetically shielded room (MSR). A flexible liquid helium (LHe) return line on the recycler is inserted into the fill port of the MEG system in the MSR through a slotted opening in the ceiling. The helium vapor is captured through a line that returns the gas to the top of the recycler assembly. A high-purity helium gas cylinder connected to the recycler assembly supplies the gas, which, after it is liquefied, increases the level of LHe in the MEG system during the start-up phase. No storage tank for evaporated helium gas nor a helium gas purifier is used. The recycler is capable of liquefying helium with a rate of ∼17 L/d after precooling the MEG system. It has provided a fully maintenance-free operation under computer control for 7 months without refill of helium. Although the recycler is used for single-orientation operation at this initial testing site, it is designed to operate at ±20° orientations, allowing the MEG system to be tilted for supine and reclining positions. Vibration of the recycler is dampened to an ultra-low level by using several vibration isolation methods, which enables uninterrupted operation during MEG measurements. Recyclers similar to this system may be quite useful even for MEG systems with 100% magnetometers.

Mechanical characterization and structural analysis of recycled fiber-reinforced-polymer resin-transfer-molded beams

NASA Astrophysics Data System (ADS)

Tan, Eugene Wie Loon

1999-09-01

The present investigation was focussed on the mechanical characterization and structural analysis of resin-transfer-molded beams containing recycled fiber-reinforced polymers. The beams were structurally reinforced with continuous unidirectional glass fibers. The reinforcing filler materials consisted entirely of recycled fiber-reinforced polymer wastes (trim and overspray). The principal resin was a 100-percent dicyclo-pentadiene unsaturated polyester specially formulated with very low viscosity for resin transfer molding. Variations of the resin transfer molding technique were employed to produce specimens for material characterization. The basic materials that constituted the structural beams, continuous-glass-fiber-reinforced, recycled-trim-filled and recycled-overspray-filled unsaturated polyesters, were fully characterized in axial and transverse compression and tension, and inplane and interlaminar shear, to ascertain their strengths, ultimate strains, elastic moduli and Poisson's ratios. Experimentally determined mechanical properties of the recycled-trim-filled and recycled-overspray-filled materials from the present investigation were superior to those of unsaturated polyester polymer concretes and Portland cement concretes. Mechanical testing and finite element analyses of flexure (1 x 1 x 20 in) and beam (2 x 4 x 40 in) specimens were conducted. These structurally-reinforced specimens were tested and analyzed in four-point, third-point flexure to determine their ultimate loads, maximum fiber stresses and mid-span deflections. The experimentally determined load capacities of these specimens were compared to those of equivalent steel-reinforced Portland cement concrete beams computed using reinforced concrete theory. Mechanics of materials beam theory was utilized to predict the ultimate loads and mid-span deflections of the flexure and beam specimens. However, these predictions proved to be severely inadequate. Finite element (fracture propagation) analyses of the flexure and beam specimens were also performed. These progressive failure analyses more closely approximated flexural behavior under actual testing conditions by reducing the elastic moduli of elements that were considered to have partially or totally failed. Individual element failures were predicted using the maximum stress, Tsai-Hill and Tsai-Wu failure criteria. Excellent predictions of flexural behavior were attributed to the progressive failure analyses combined with an appropriate failure criterion, and the reliable input material properties that were generated.

Corrosion Behavior of Steel Reinforcement in Concrete with Recycled Aggregates, Fly Ash and Spent Cracking Catalyst.

PubMed

Gurdián, Hebé; García-Alcocel, Eva; Baeza-Brotons, Francisco; Garcés, Pedro; Zornoza, Emilio

2014-04-21

The main strategy to reduce the environmental impact of the concrete industry is to reuse the waste materials. This research has considered the combination of cement replacement by industrial by-products, and natural coarse aggregate substitution by recycled aggregate. The aim is to evaluate the behavior of concretes with a reduced impact on the environment by replacing a 50% of cement by industrial by-products (15% of spent fluid catalytic cracking catalyst and 35% of fly ash) and a 100% of natural coarse aggregate by recycled aggregate. The concretes prepared according to these considerations have been tested in terms of mechanical strengths and the protection offered against steel reinforcement corrosion under carbonation attack and chloride-contaminated environments. The proposed concrete combinations reduced the mechanical performance of concretes in terms of elastic modulus, compressive strength, and flexural strength. In addition, an increase in open porosity due to the presence of recycled aggregate was observed, which is coherent with the changes observed in mechanical tests. Regarding corrosion tests, no significant differences were observed in the case of the resistance of these types of concretes under a natural chloride attack. In the case of carbonation attack, although all concretes did not stand the highly aggressive conditions, those concretes with cement replacement behaved worse than Portland cement concretes.

Correlation analysis between sulphate content and leaching of sulphates in recycled aggregates from construction and demolition wastes.

PubMed

Barbudo, Auxi; Galvín, Adela P; Agrela, Francisco; Ayuso, Jesús; Jiménez, Jose Ramón

2012-06-01

In some recycled aggregates applications, such as component of new concrete or roads, the total content of soluble sulphates should be measured and controlled. Restrictions are usually motivated by the resistance or stability of the new structure, and in most cases, structural concerns can be remedied by the use of techniques such as sulphur-resistant cements. However, environmental risk assessment from recycling and reuse construction products is often forgotten. The purpose of this study is to analyse the content of soluble sulphate on eleven recycled aggregates and six samples prepared in laboratory by the addition of different gypsum percentages. As points of reference, two natural aggregates were tested. An analysis of the content of the leachable amount of heavy metals regulated by European regulation was included. As a result, the correlation between solubility and leachability data allow suggest a limiting gypsum amount of 4.4% on recycled aggregates. This limit satisfies EU Landfill Directive criteria, which is currently used as reference by public Spanish Government for recycled aggregates in construction works. Copyright © 2012 Elsevier Ltd. All rights reserved.

Virus fate and transport during recharge using recycled water at a research field site in the Montebello Forebay, Los Angeles County, California, 1997-2000

USGS Publications Warehouse

Anders, Robert; Yanko, William A.; Schroeder, Roy A.; Jackson, James L.

2004-01-01

Total and fecal coliform bacteria distributions in subsurface water samples collected at a research field site in Los Angeles County were found to increase from nondetectable levels immediately before artificial recharge using tertiary-treated municipal wastewater (recycled water). This rapid increase indicates that bacteria can move through the soil with the percolating recycled water over intervals of a few days and vertical and horizontal distances of about 3 meters. This conclusion formed the basis for three field-scale experiments using bacterial viruses (bacteriophage) MS2 and PRD1 as surrogates for human enteric viruses and bromide as a conservative tracer to determine the fate and transport of viruses in recycled water during subsurface transport under actual recharge conditions. The research field site consists of a test basin constructed adjacent to a large recharge facility (spreading grounds) located in the Montebello Forebay of Los Angeles County, California. The soil beneath the test basin is predominantly medium to coarse, moderately sorted, grayish-brown sand. The three tracer experiments were conducted during August 1997, August-September 1998, and August 2000. For each experiment, prepared solutions of bacteriophage and bromide were sprayed on the surface of the water in the test basin and injected, using peristaltic pumps, directly into the feed pipe delivering the recycled water to the test basin. Extensive data were obtained for water samples collected from the test basin itself and from depths of 0.3, 0.6, 1.0, 1.5, 3.0, and 7.6 meters below the bottom of the test basin. The rate of bacteriophage inactivation in the recycled water, independent of any processes occurring in the subsurface, was determined from measurements on water samples from the test basin. Regression analysis of the ratios of bacteriophage to bromide was used to determine the attenuation rates for MS2 and PRD1, defined as the logarithmic reduction in the ratio during each experiment. Although the inactivation rates increased during the third tracer experiment, they were nearly two orders of magnitude less than the attenuation rates. Therefore, adsorption, not inactivation, is the predominant removal mechanism for viruses during artificial recharge. Using the colloid-filtration model, the collision efficiency was determined for both bacteriophage during the second and third field-scale tracer experiments. The collision efficiency confirms that more favorable attachment conditions existed for PRD1, especially during the third tracer experiment. The different collision efficiencies between the second and third tracer experiments possibly were due to changing hydraulic conditions at the research field site during each experiment. The field data suggest that an optimal management scenario might exist to maximize the amount of recycled water that can be applied to the spreading grounds while still maintaining favorable attachment conditions for virus removal and thereby ensuring protection of the ground-water supply.

Advanced in-duct sorbent injection for SO{sub 2} control. Topical report No. 2, Subtask 2.2: Design optimization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rosenhoover, W.A.; Stouffer, M.R.; Withum, J.A.

1994-12-01

The objective of this research project is to develop second-generation duct injection technology as a cost-effective SO{sub 2} control option for the 1990 Clean Air Act Amendments. Research is focused on the Advanced Coolside process, which has shown the potential for achieving the performance targets of 90% SO{sub 2} removal and 60% sorbent utilization. In Subtask 2.2, Design Optimization, process improvement was sought by optimizing sorbent recycle and by optimizing process equipment for reduced cost. The pilot plant recycle testing showed that 90% SO{sub 2} removal could be achieved at sorbent utilizations up to 75%. This testing also showed thatmore » the Advanced Coolside process has the potential to achieve very high removal efficiency (90 to greater than 99%). Two alternative contactor designs were developed, tested and optimized through pilot plant testing; the improved designs will reduce process costs significantly, while maintaining operability and performance essential to the process. Also, sorbent recycle handling equipment was optimized to reduce cost.« less

Impact of recycling on the mechanical and thermo-mechanical properties of wood flour/high density polyethylene and wood flour/poly lactic acid composites

NASA Astrophysics Data System (ADS)

Bhattacharjee, Sujal

This research concentrates on the recyclability of two wood plastic composites (WPCs)--wood flour/HDPE and wood flour/PLA composites. Two different filler loadings (30 and 50 wt%) were considered for each polymer composite. Each composite formulation contained 3 wt% of a coupling agent, and was individually recycled up to six times by extrusion process. Samples for mechanical and thermo-mechanical tests were prepared by injection molding. All test results were statistically analyzed with a confidence level of 95%. Additional tests such as fiber length measurement, GPC, DSC, TGA, FTIR, and SEM were also performed at specific reprocessing cycles. After reprocessing six times, all formulations showed lower relative decrease in most stiffness properties but higher relative increase in most strain properties. In strength properties, both HDPE composites showed lower relative decrease after reprocessed six times; however, higher and lower filler PLA composites showed sharp decrease reprocessed at second and six times respectively.

Microstructure of Concrete with Aggregates from Construction and Demolition Waste Recycling Plants.

PubMed

Bravo, Miguel; Santos Silva, António; de Brito, Jorge; Evangelista, Luís

2016-02-01

This paper intends to analyze the microstructure of concrete with recycled aggregates (RA) from construction and demolition waste from various Portuguese recycling plants. To that effect, several scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) analyses were performed. Various concrete mixes were evaluated in order to analyze the influence of the RA's collection point and consequently of their composition on the mixes' characteristics. Afterward all the mixes were subjected to the capillary water absorption test in order to quantitatively evaluate their porosity. Results from the SEM/EDS analysis were compared with those from capillary water absorption test. The SEM/EDS analysis showed that the bond capacity of aggregates to the new cement paste is greatly influenced by the RA's nature. On the other hand, there was an increase in porosity with the incorporation of RA.

Consumer-mediated recycling and cascading trophic interactions.

PubMed

Leroux, Shawn J; Loreau, Michel

2010-07-01

Cascading trophic interactions mediated by consumers are complex phenomena, which encompass many direct and indirect effects. Nonetheless, most experiments and theory on the topic focus uniquely on the indirect, positive effects of predators on producers via regulation of herbivores. Empirical research in aquatic ecosystems, however, demonstrate that the indirect, positive effects of consumer-mediated recycling on primary producer stocks may be larger than the effects of herbivore regulation, particularly when predators have access to alternative prey. We derive an ecosystem model with both recipient- and donor-controlled trophic relationships to test the conditions of four hypotheses generated from recent empirical work on the role of consumer-mediated recycling in cascading trophic interactions. Our model predicts that predator regulation of herbivores will have larger, positive effects on producers than consumer-mediated recycling in most cases but that consumer-mediated recycling does generally have a positive effect on producer stocks. We demonstrate that herbivore recycling will have larger effects on producer biomass than predator recycling when turnover rates and recycling efficiencies are high and predators prefer local prey. In addition, predictions suggest that consumer-mediated recycling has the largest effects on primary producers when predators prefer allochthonous prey and predator attack rates are high. Finally, our model predicts that consumer-mediated recycling effects may not be largest when external nutrient loading is low. Our model predictions highlight predator and prey feeding relationships, turnover rates, and external nutrient loading rates as key determinants of the strength of cascading trophic interactions. We show that existing hypotheses from specific empirical systems do not occur under all conditions, which further exacerbates the need to consider a broad suite of mechanisms when investigating trophic cascades.

Recycling stainless steel orthodontic brackets with Er:YAG laser - An environmental scanning electron microscope and shear bond strength study.

PubMed

Chacko, Prince K; Kodoth, Jithesh; John, Jacob; Kumar, Kishore

2013-07-01

TO DETERMINE THE EFFICIENCY OF ERBIUM: Yttrium aluminum garnet (Er:YAG) laser with Environmental Scanning Electron Microscope (ESEM) and shear bond strength analysis as a method of recycling stainless steel orthodontic brackets and compare with other methods of recycling. Eighty samples of extracted premolar teeth bonded to SS brackets were tested for rebonded shear bond strength after recycling by four methods and compared with a control group of 20 samples. These 80 samples were randomized into four groups which were recycled by four methods, namely, sandblasting, thermal method, adhesive grinding by tungsten carbide bur, and Er: YAG laser method. After recycling, ESEM and shear bond strength analysis were used to analyze the efficiency of the recycling methods. ER: YAG laser group was found to be having the greatest bond strength among the recycled brackets (8.33±2.51 followed by the sandblasting at 6.12±1.12 MPa, thermal and electropolishing at 4.44±0.95 MPa, and lastly the adhesive grinding method at 3.08±1.07 MPa. The shear bond strength of Er: YAG laser group was found to be having no statistically significant difference with that of the control group (P>0.05 and had statistical signifance with sandblasting, thermal and electropolishing and adhesive grinding groups at P>0.001. ESEM analysis showed complete removal of adhesive from the brackets recycled with Er: YAG laser which mimicked that of the control group. ER: YAG laser (2940 nm) was found to be the most efficient method for recycling, followed by the sandblasting, thermal, and the tungsten carbide methods, which had the least shear bond strength value and is not fit for clinical usage.

Focussing on recycling attitudes of engineering students at UiTM Shah Alam - towards zero discharge

NASA Astrophysics Data System (ADS)

Sharifah, A. S. A. K.; Khamaruddin, P. F. M.; Mohamad, N. N.; Saharuddin, M. Q.

2018-03-01

The generation of municipal solid waste (MSW) in Malaysia over the past 10 years has increased by 95 percent due to rapid development in the urban areas. 16.76 million tonne of waste is expected to be generated by Malaysian in the year 2020. Presently, there are about 70 percent of waste produced reported to be collected and 95 percent of it are disposed in landfills with only 5 percent left are being recycled. A 40 percent reduction of waste disposed to landfill by year 2020, through recycling and intermediate treatments such as waste to energy, composting and material recovery is very much needed as opening new landfills are not socially attractive. It clearly shows the awareness in reducing waste through recycling is still at infancy among Malaysians. Hence, a proper solid waste management should be enhanced through education among youngsters to ensure an integrated solid waste management towards zero discharge is achievable. The purpose of the research is two-fold. Firstly, to determine the recycling practices awareness among engineering students through manual and on-line survey. Secondly, a study on the effectiveness of recycling bins at the engineering students’ centre. The data collected were analyzed using statistical analysis. Results show that there is significant relationship (p<0.05) between gender and knowledge on recycling using Chi square test. However, there is an insignificant relationship (p>0.05) between knowledge and awareness of students towards recycling using partial correlation. Nevertheless, it is important to note that recycling practices through the provision of well-designed recycling bins and continuous education will ensure a sound society upholding a Zero Discharge attitude in the future.

Life cycle assessment of post-consumer plastics production from waste electrical and electronic equipment (WEEE) treatment residues in a Central European plastics recycling plant.

PubMed

Wäger, Patrick A; Hischier, Roland

2015-10-01

Plastics play an increasingly important role in reaching the recovery and recycling rates defined in the European WEEE Directive. In a recent study we have determined the life cycle environmental impacts of post-consumer plastics production from mixed, plastics-rich WEEE treatment residues in the Central European plant of a market-leading plastics recycler, both from the perspective of the customers delivering the residues and the customers buying the obtained post-consumer recycled plastics. The results of our life cycle assessments, which were extensively tested with sensitivity analyses, show that from both perspectives plastics recycling is clearly superior to the alternatives considered in this study (i.e. municipal solid waste incineration (MSWI) and virgin plastics production). For the three ReCiPe endpoint damage categories, incineration in an MSWI plant results in an impact exceeding that of the examined plastics recycling facility each by about a factor of 4, and the production of virgin plastics has an impact exceeding that of the post-consumer recycled (PCR) plastics production each by a factor of 6-10. On a midpoint indicator level the picture is more differentiated, showing that the environmental impacts of the recycling options are lower by 50% and more for almost all impact factors. While this provides the necessary evidence for the environmental benefits of plastics recycling compared to existing alternatives, it can, however, not be taken as conclusive evidence. To be conclusive, future research will have to address the fate of hazardous substances in the outputs of such recycling systems in more detail. Copyright © 2015 Elsevier B.V. All rights reserved.

Effect of fly ash on the strength of porous concrete using recycled coarse aggregate to replace low-quality natural coarse aggregate

NASA Astrophysics Data System (ADS)

Arifi, Eva; Cahya, Evi Nur; Christin Remayanti, N.

2017-09-01

The performance of porous concrete made of recycled coarse aggregate was investigated. Fly ash was used as cement partial replacement. In this study, the strength of recycled aggregate was coMPared to low quality natural coarse aggregate which has high water absorption. Compression strength and tensile splitting strength test were conducted to evaluate the performance of porous concrete using fly ash as cement replacement. Results have shown that the utilization of recycled coarse aggregate up to 75% to replace low quality natural coarse aggregate with high water absorption increases compressive strength and splitting tensile strength of porous concrete. Using fly ash up to 25% as cement replacement improves compressive strength and splitting tensile strength of porous concrete.

Development of USPS Laboratory and pilot-scale testing protocols

Treesearch

Carl Houtman; Nancy Ross Sutherland; David Bormett; Donald Donermeyer

2000-01-01

The ultimate goal of the US Postal Service (USPS) Environmentally Benign Stamp Program is to develop stamp adhesives that can be removed by unit operations found in recycling mills. The maintenance of final product quality specifications for a recycling mill while loading the feedstock with a significant quantity of adhesive is the criterion for success of this program...

Recycled fiber quality from a laboratory-scale blade separator/blend

Treesearch

Bei-Hong Liang; Stephen M. Shaler; Laurence Mott; Leslie Groom

1994-01-01

A simple and inexpensive fiber separator/blender was developed to generate useful secondary fibers from hydropulped waste paper. Processing wet hydropulped fiber resulted in a furnish with no change in average fiber length in three out of four types of recycled fibers tested. In all cases, the Canadian Standard freeness increased after processing compared to...

The tensile testing of individual wood fibers using environmental scanning electron microscopy and video image analysis

Treesearch

Laurence Mott; Stephen M. Shaler; Leslie H. Groom; Bei-Hong Liang

1995-01-01

Relationships between virgin fiber types, fiber production techniques and mechanical properties are well understood and documented. For recycled fivers, however, these same relationships are confounded by unquantified degrees of further mechanical and chemical damage. To gain a more comprehensive understanding of the impact of recycling on secondary fibers, the...

Recycled fiber quality from a laboratory-scale blade separator/blender

Treesearch

Bei-Hong Liang; Stephen M. Shaler; Laurence Mott; Leslie Groom

1994-01-01

A simple and inexpensive fiber separator/blender was developed to generate useful secondary fibers from hydropulped waste paper. Processing wet hydropulped fiber resulted in a furnish with no change in average fiber length in three out of four types of recycled fibers tested. In all cases, the canadian standard freeness increased after processing compared to...

The tensile testing of individual wood fibers using environmental scanning electron microscopy and video image analysis

Treesearch

Laurence Mott; Stephen M. Shaler; Leslie H. Groom; Bei-Hong Liang

1995-01-01

Relationships between virgin fiber types, fiber production techniques and mechanical properties are well understood and documented. For recycled fibers, however, these same relationships are confounded by unquantified degrees of further mechanical and chemical damage. To gain a more comprehensive understanding of the impact of recycling on secondary fibers, the...

Compatibility of pressure sensitive adhesives with recycling unit operations

Treesearch

David Bormett; Carl Houtman; Said Abubakr; Joseph Peng

1999-01-01

Removal of pressure sensitive adhesives (PSAs) from recovered paper is a major problem facing the paper recycling industry. As a result of a United States Postal Service (USPS) initiative, which currently purchases about 12% of domestic PSA production, a team was formed consisting of representatives from the USPS, the Forest Products Laboratory, Springborn Testing and...

Measuring Individual Skills in Household Waste Recycling: Implications for Citizens' Education and Communication in Six Urban Contexts

ERIC Educational Resources Information Center

Passafaro, Paola; Bacciu, Anna; Caggianelli, Ilaria; Castaldi, Viviana; Fucci, Eleonora; Ritondale, Deborah; Trabalzini, Eleonora

2016-01-01

This article reports the analysis of six urban contexts in which a practical tool measuring individual skills concerning household waste recycling was tested. The tool is a structured questionnaire including a simulation task that assesses respondents' abilities to sort household waste adequately in a given context/municipality. Results indicate…

Study the complexity and control of the recycling-supply chain of China's color TVs market based on the government subsidy

NASA Astrophysics Data System (ADS)

Xie, Lei; Ma, Junhai

2016-09-01

In these days, as the recycling of household appliances becomes increasingly popular, the recycling network tends to be perfect in television industry. This paper focuses on the game among two recyclers and a processor in a Duopoly market of color TV recycling. We find that if the adjustment coefficients of the decision variables are changed abruptly, the system will fall into chaotic state. In order to avoid hazard of falling into a chaotic state, we adopt the method of delay control, providing the manufacturers with effective measures about chaos control. This paper analyzes the system's reactions to government decision, finding that when the parameters become beneficial for manufacturers, consumers and the environment, the system will fall into chaos and system's regional stability will reduce. Resulting from our analysis, this paper gives advice on the improvement of the environment and enhance in social welfare. Tested through the data we collected, this study is practical in both its theory and its applicability.

The Effects of Different Fine Recycled Concrete Aggregates on the Properties of Mortar

PubMed Central

Fan, Cheng-Chih; Huang, Ran; Hwang, Howard; Chao, Sao-Jeng

2015-01-01

The practical use of recycled concrete aggregate produced by crushing concrete waste reduces the consumption of natural aggregate and the amount of concrete waste that ends up in landfills. This study investigated two methods used in the production of fine recycled concrete aggregate: (1) a method that produces fine as well as coarse aggregate, and (2) a method that produces only fine aggregate. Mortar specimens were tested using a variety of mix proportions to determine how the characteristics of fine recycled concrete aggregate affect the physical and mechanical properties of the resulting mortars. Our results demonstrate the superiority of mortar produced using aggregate produced using the second of the two methods. Nonetheless, far more energy is required to render concrete into fine aggregate than is required to produce coarse as well as fine aggregate simultaneously. Thus, the performance benefits of using only fine recycled concrete aggregate must be balanced against the increased impact on the environment.

Testing of advanced liquefaction concepts in HTI Run ALC-1: Coal cleaning and recycle solvent treatment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Robbins, G.A.; Winschel, R.A.; Burke, F.P.

In 1991, the Department of Energy initiated the Advanced Liquefaction Concepts Program to promote the development of new and emerging technology that has potential to reduce the cost of producing liquid fuels by direct coal liquefaction. Laboratory research performed by researchers at CAER, CONSOL, Sandia, and LDP Associates in Phase I is being developed further and tested at the bench scale at HTI. HTI Run ALC-1, conducted in the spring of 1996, was the first of four planned tests. In Run ALC-1, feed coal ash reduction (coal cleaning) by oil agglomeration, and recycle solvent quality improvement through dewaxing and hydrotreatmentmore » of the recycle distillate were evaluated. HTI`s bench liquefaction Run ALC-1 consisted of 25 days of operation. Major accomplishments were: 1) oil agglomeration reduced the ash content of Black Thunder Mine coal by 40%, from 5.5% to 3.3%; 2) excellent coal conversion of 98% was obtained with oil agglomerated coal, about 3% higher than the raw Black Thunder Mine coal, increasing the potential product yield by 2-3% on an MAF coal basis; 3) agglomerates were liquefied with no handling problems; 4) fresh catalyst make-up rate was decreased by 30%, with no apparent detrimental operating characteristics, both when agglomerates were fed and when raw coal was fed (with solvent dewaxing and hydrotreating); 5) recycle solvent treatment by dewaxing and hydrotreating was demonstrated, but steady-state operation was not achieved; and 6) there was some success in achieving extinction recycle of the heaviest liquid products. Performance data have not been finalized; they will be available for full evaluation in the new future.« less

Recyclability of PET/WPI/PE Multilayer Films by Removal of Whey Protein Isolate-Based Coatings with Enzymatic Detergents

PubMed Central

Cinelli, Patrizia; Schmid, Markus; Bugnicourt, Elodie; Coltelli, Maria Beatrice; Lazzeri, Andrea

2016-01-01

Multilayer plastic films provide a range of properties, which cannot be obtained from monolayer films but, at present, their recyclability is an open issue and should be improved. Research to date has shown the possibility of using whey protein as a layer material with the property of acting as an excellent barrier against oxygen and moisture, replacing petrochemical non-recyclable materials. The innovative approach of the present research was to achieve the recyclability of the substrate films by separating them, with a simple process compatible with industrial procedures, in order to promote recycling processes leading to obtain high value products that will beneficially impact the packaging and food industries. Hence, polyethyleneterephthalate (PET)/polyethylene (PE) multi-layer film was prepared based on PET coated with a whey protein layer, and then the previous structure was laminated with PE. Whey proteins, constituting the coating, can be degraded by enzymes so that the coating films can be washed off from the plastic substrate layer. Enzyme types, dosage, time, and temperature optima, which are compatible with procedures adopted in industrial waste recycling, were determined for a highly-efficient process. The washing of samples based on PET/whey and PET/whey/PE were efficient when performed with enzymatic detergent containing protease enzymes, as an alternative to conventional detergents used in recycling facilities. Different types of enzymatic detergents tested presented positive results in removing the protein layer from the PET substrate and from the PET/whey/PE multilayer films at room temperature. These results attested to the possibility of organizing the pre-treatment of the whey-based multilayer film by washing with different available commercial enzymatic detergents in order to separate PET and PE, thus allowing a better recycling of the two different polymers. Mechanical properties of the plastic substrate, such as stress at yield, stress and elongation at break, evaluated by tensile testing on films before and after cleaning, were are not significantly affected by washing with enzymatic detergents. PMID:28773592

Safety evaluation of mechanical recycling processes used to produce polyethylene terephthalate (PET) intended for food contact applications.

PubMed

Barthélémy, E; Spyropoulos, D; Milana, M-R; Pfaff, K; Gontard, N; Lampi, E; Castle, L

2014-01-01

The development of a scheme for the safety evaluation of mechanical recycling processes for polyethylene terephthalate (PET) is described. The starting point is the adoption of a threshold of toxicological concern such that migration from the recycled PET should not give rise to a dietary exposure exceeding 0.0025 μg kg(-1) bw day(-1), the exposure threshold value for chemicals with structural alerts raising concern for potential genotoxicity, below which the risk to human health would be negligible. It is practically impossible to test every batch of incoming recovered PET and every production batch of recycled PET for all the different chemical contaminants that could theoretically arise. Consequently, the principle of the safety evaluation is to measure the cleaning efficiency of a recycling process by using a challenge test with surrogate contaminants. This cleaning efficiency is then applied to reduce a reference contamination level for post-consumer PET, conservatively set at 3 mg kg(-1) PET for a contaminant resulting from possible misuse by consumers. The resulting residual concentration of each contaminant in recycled PET is used in conservative migration models to calculate migration levels, which are then used along with food consumption data to give estimates of potential dietary exposure. The default scenario, when the recycled PET is intended for general use, is that of an infant weighing 5 kg and consuming every day powdered infant formula reconstituted with 0.75 L of water coming from water bottles manufactured with 100% recycled PET. According to this scenario, it can be derived that the highest concentration of a substance in water that would ensure that the dietary exposure of 0.0025 µg kg(-1) bw day(-1) is not exceeded, is 0.017 μg kg(-1) food. The maximum residual content that would comply with this migration limit depends on molecular weight and is in the range 0.09-0.32 mg kg(-1) PET for the typical surrogate contaminants.

Corrosion Behavior of Steel Reinforcement in Concrete with Recycled Aggregates, Fly Ash and Spent Cracking Catalyst

PubMed Central

Gurdián, Hebé; García-Alcocel, Eva; Baeza-Brotons, Francisco; Garcés, Pedro; Zornoza, Emilio

2014-01-01

The main strategy to reduce the environmental impact of the concrete industry is to reuse the waste materials. This research has considered the combination of cement replacement by industrial by-products, and natural coarse aggregate substitution by recycled aggregate. The aim is to evaluate the behavior of concretes with a reduced impact on the environment by replacing a 50% of cement by industrial by-products (15% of spent fluid catalytic cracking catalyst and 35% of fly ash) and a 100% of natural coarse aggregate by recycled aggregate. The concretes prepared according to these considerations have been tested in terms of mechanical strengths and the protection offered against steel reinforcement corrosion under carbonation attack and chloride-contaminated environments. The proposed concrete combinations reduced the mechanical performance of concretes in terms of elastic modulus, compressive strength, and flexural strength. In addition, an increase in open porosity due to the presence of recycled aggregate was observed, which is coherent with the changes observed in mechanical tests. Regarding corrosion tests, no significant differences were observed in the case of the resistance of these types of concretes under a natural chloride attack. In the case of carbonation attack, although all concretes did not stand the highly aggressive conditions, those concretes with cement replacement behaved worse than Portland cement concretes. PMID:28788613

Assessing the variables affecting on the rate of solid waste generation and recycling: An empirical analysis in Prespa Park.

PubMed

Grazhdani, Dorina

2016-02-01

Economic development, urbanization, and improved living standards increase the quantity and complexity of generated solid waste. Comprehensive study of the variables influencing household solid waste production and recycling rate is crucial and fundamental for exploring the generation mechanism and forecasting future dynamics of household solid waste. The present study is employed in the case study of Prespa Park. A model, based on the interrelationships of economic, demographic, housing structure and waste management policy variables influencing the rate of solid waste generation and recycling is developed and employed. The empirical analysis is based on the information derived from a field questionnaire survey conducted in Prespa Park villages for the year 2014. Another feature of this study is to test whether a household's waste generation can be decoupled from its population growth. Descriptive statistics, bivariate correlation analysis and F-tests are used to know the relationship between variables. One-way and two-way fixed effects models data analysis techniques are used to identify variables that determine the effectiveness of waste generation and recycling at household level in the study area. The results reveal that households with heterogeneous characteristics, such as education level, mean building age and income, present different challenges of waste reduction goals. Numerically, an increase of 1% in education level of population corresponds to a waste reduction of 3kg on the annual per capita basis. A village with older buildings, in the case of one year older of the median building age, corresponds to a waste generation increase of 12kg. Other economic and policy incentives such as the mean household income, pay-as-you-throw, percentage of population with access to curbside recycling, the number of drop-off recycling facilities available per 1000 persons and cumulative expenditures on recycling education per capita are also found to be effective measures in waste reduction. The mean expenditure for recycling education spent on a person for years 2010 and 2014 is 12 and 14 cents, respectively and it vary from 0 to €1. For years 2010 and 2014, the mean percentage of population with access to curbside recycling services is 38.6% and 40.3%, and the mean number of drop-off recycling centers per 1000 persons in the population is 0.29 and 0.32, respectively. Empirical evidence suggests that population growth did not necessarily result in increases in waste generation. The results provided are useful when planning, changing or implementing sustainable municipal solid waste management. Copyright © 2015 Elsevier Ltd. All rights reserved.

Nutrient recycling of lipid-extracted waste in the production of an oleaginous thraustochytrid.

PubMed

Lowrey, Joshua; Brooks, Marianne S; Armenta, Roberto E

2016-05-01

Improving the economics of microalgae production for the recovery of microbial oil requires a comprehensive exploration of the measures needed to improve productivity as well as to reduce the overall processing costs. One avenue for cost reduction involves recycling the effluent waste water remaining after lipid extraction. This study investigates the feasibility of recycling those wastes for growing thraustochytrid biomass, a heterotrophic microalgae, where wastes were generated from the enzymatic extraction of the lipids from the cell biomass. It was demonstrated that secondary cultures of the tested thraustochytrid grown in the recycled wastes performed favorably in terms of cell and oil production (20.48 g cells L(-1) and 40.9 % (w/w) lipid) compared to the control (13.63 g cells L(-1) and 56.8 % (w/w) lipid). Further, the significant uptake of solubilized cell material (in the form of amino acids) demonstrated that the recycled waste has the potential for offsetting the need for fresh medium components. These results indicate that the implementation of a nutrient recycling strategy for industrial microalgae production could be possible, with significant added benefits such as conserving water resources, improving production efficiency, and decreasing material inputs.

Preliminary result on the enhancement of Ufer electrodes using recycle additives materials

NASA Astrophysics Data System (ADS)

Zulkifli, Muhammad Haziq Aniq Bin; Ahmad, Hussein Bin

2016-11-01

Ground building pillars is to be used as ground rod. The pillars are design, fabricated, and formulated with new ground fillers. The additives will be used from recycle waste materials mainly from the palm oil plant process. Micro scale building pillars will be fabricated and install in the test ground at all of the location. Earth tester meter are used to measure and collect the data of the soil resistivity when the research is conducted. In collecting these data, 3-terminal methods are used to carry the measurements. This experiment will be conducted for 30 weeks and regular measurements at the test ground copper grids will be conducted to measure the ground electrode resistance. The study will mainly base on IEC 62503-3. The used of reinforcing rods and mixture of recycle additives could produce a better grounding system that are suitable and can be used in all kind of soil condition and large industries.

Fabrication of recyclable and durable superhydrophobic materials with wear/corrosion-resistance properties from kaolin and polyvinylchloride

NASA Astrophysics Data System (ADS)

Qu, Mengnan; Liu, Shanshan; He, Jinmei; Feng, Juan; Yao, Yali; Ma, Xuerui; Hou, Lingang; Liu, Xiangrong

2017-07-01

In this study, mechanically stable and recyclable superhydrophobic materials were prepared from polyvinylchloride (PVC) and kaolin nanoparticles modified by stearic acid using a simple and low-cost drop-coating. The obtained materials displayed liquid-repellent toward water and several other liquids of daily life (such as orange juice, coffee, milk, coca cola and ink). These superhydrophobic materials showed remarkable robustness against sandpaper abrasion, UV-irradiation and ultrasonication test, while retaining its superhydrophobicity even after 60 abrasion cycles loaded of 500 g with sandpaper, 7 days UV-irradiation or 120 min ultrasonication test. The excellent durability against complex conditions was attributed to the hierarchical structure and strong interfacial adhesion of the materials. More significantly, the materials used in the coating could be recycled and reconstructed without losing its superhydrophobicity. The current superhydrophobic materials tolerate rigorous environment, opening a new avenue to a variety of practical applications.

Experimental investigation of the quality characteristics of agricultural plastic wastes regarding their recycling and energy recovery potential

DOE Office of Scientific and Technical Information (OSTI.GOV)

Briassoulis, D., E-mail: briassou@aua.gr; Hiskakis, M.; Babou, E.

2012-06-15

Highlights: Black-Right-Pointing-Pointer Definition of parameters characterising agricultural plastic waste (APW) quality. Black-Right-Pointing-Pointer Analysis of samples to determine APW quality for recycling or energy recovery. Black-Right-Pointing-Pointer Majority of APW samples from various countries have very good quality for recycling. Black-Right-Pointing-Pointer Upper limit of 50% w/w soil contamination in APW acceptable for energy recovery. Black-Right-Pointing-Pointer Chlorine and heavy metals content in APW below the lowest limit for energy recovery. - Abstract: A holistic environmentally sound waste management scheme that transforms agricultural plastic waste (APW) streams into labelled guaranteed quality commodities freely traded in open market has been developed by the European researchmore » project LabelAgriWaste. The APW quality is defined by the APW material requirements, translated to technical specifications, for recycling or energy recovery. The present work investigates the characteristics of the APW quality and the key factors affecting it from the introduction of the virgin product to the market to the APW stream reaching the disposer. Samples of APW from different countries were traced from their application to the field through their storage phase and transportation to the final destination. The test results showed that the majority of APW retained their mechanical properties after their use preserving a 'very good quality' for recycling in terms of degradation. The degree of soil contamination concerning the APW recycling and energy recovery potential fluctuates depending on the agricultural plastic category and application. The chlorine and heavy metal content of the tested APW materials was much lower than the maximum acceptable limits for their potential use in cement industries.« less

Characterization of wood mulch and leachate/runoff from three wood recycling facilities.

PubMed

Kannepalli, Sarat; Strom, Peter F; Krogmann, Uta; Subroy, Vandana; Giménez, Daniel; Miskewitz, Robert

2016-11-01

Large-scale open storage of wood mulch is common practice at wood recycling facilities. During rain and snow melt, leachate with soluble compounds and suspended particles is released from mulch stockpiles. The objective of this study was to determine the quality of leachate/runoff from wood recycling facilities to evaluate its potential to contaminate receiving waterbodies. Wood mulch (n = 30) and leachate/runoff (n = 26) samples were collected over 1.5 years from three wood recycling facilities in New Jersey, USA. Differences by site were found (p < 0.05) for most of the 21 constituents tested in the solid wood mulch samples. Biochemical oxygen demand (range <20-3000 mg/L), chemical oxygen demand (134-6000 mg/L) and total suspended solids (69-401 mg/L) median concentrations of the leachate/runoff samples were comparable to those of untreated domestic wastewater. Total Kjeldahl N, total P and fecal coliform median values were slightly lower than typical wastewater values. Dose-response studies with leachate/runoff samples using zebrafish (Danio rerio) embryos showed that mortality and developmental defects typically did not occur even at the highest concentration tested, indicating low toxicity, although delayed development did occur. Based on this study, leachate/runoff from wood recycling facilities should not be released to surface waters as it is a potential source of organic contamination and low levels of nutrients. A study in which runoff from a controlled drainage area containing wood mulch of known properties is monitored would allow for better assessment of the potential impact of stormwater runoff from wood recycling facilities. Copyright © 2016 Elsevier Ltd. All rights reserved.

Characteristics of Recycled Concrete Aggregates from Precast Slab Block Buildings

NASA Astrophysics Data System (ADS)

Venkrbec, Václav; Nováková, Iveta; Henková, Svatava

2017-10-01

Precast slab block buildings (PSBB) typically and frequently occur in Central and Eastern Europe, as well as elsewhere in the world. Some of these buildings are currently used beyond their service life capacity. The utilization of recycled materials from these buildings with regard to applying the principles of sustainable construction and using recycled materials will probably be significant in the following years. Documentation from the manufacturing processes of prefabricated blocks for precast slab block buildings is not available, and also it is difficult to declare technological discipline during the construction of these buildings. Therefore, properties of recycled concrete aggregates (RCA) produced from construction and demolition waste (C&DW) of precast slab block buildings build between 1950s to 1990s are not sufficiently known. The demolition of these buildings is very rare today, but it can be assumed an increase in demolitions of these buildings in the future. The use of RCA in new concrete requires verification/testing of the geometrical and physical properties of RCA according to the EN 12 620+A1 standard. The aim of the contribution is to present a case study of the demolition of slab block building with emphasis on RCA usage. The paper presents the results of the tests according to European standards for determining selected geometrical and physical properties of the RCA. The paper describes and evaluates tests such as determination of particle size distribution - Sieve Analysis, content of fine particles, determination of density and water absorption. The results of the properties testing of RCA are compared with the properties of natural aggregate. The general boundary conditions of RCA particular tests are presented.

New Hampshire binder and mix review.

DOT National Transportation Integrated Search

2012-08-01

This review was initiated to compare relative rut testing and simple performance tests (now known as Asphalt Mix : Performance Tests) for the New Hampshire inch mix with 15% Recycled Asphalt Pavement (RAP). The tested mixes were : made from ...

Experimental investigation of the quality characteristics of agricultural plastic wastes regarding their recycling and energy recovery potential.

PubMed

Briassoulis, D; Hiskakis, M; Babou, E; Antiohos, S K; Papadi, C

2012-06-01

A holistic environmentally sound waste management scheme that transforms agricultural plastic waste (APW) streams into labelled guaranteed quality commodities freely traded in open market has been developed by the European research project LabelAgriWaste. The APW quality is defined by the APW material requirements, translated to technical specifications, for recycling or energy recovery. The present work investigates the characteristics of the APW quality and the key factors affecting it from the introduction of the virgin product to the market to the APW stream reaching the disposer. Samples of APW from different countries were traced from their application to the field through their storage phase and transportation to the final destination. The test results showed that the majority of APW retained their mechanical properties after their use preserving a "very good quality" for recycling in terms of degradation. The degree of soil contamination concerning the APW recycling and energy recovery potential fluctuates depending on the agricultural plastic category and application. The chlorine and heavy metal content of the tested APW materials was much lower than the maximum acceptable limits for their potential use in cement industries. Copyright © 2012 Elsevier Ltd. All rights reserved.

Interval linear programming model for long-term planning of vehicle recycling in the Republic of Serbia under uncertainty.

PubMed

Simic, Vladimir; Dimitrijevic, Branka

2015-02-01

An interval linear programming approach is used to formulate and comprehensively test a model for optimal long-term planning of vehicle recycling in the Republic of Serbia. The proposed model is applied to a numerical case study: a 4-year planning horizon (2013-2016) is considered, three legislative cases and three scrap metal price trends are analysed, availability of final destinations for sorted waste flows is explored. Potential and applicability of the developed model are fully illustrated. Detailed insights on profitability and eco-efficiency of the projected contemporary equipped vehicle recycling factory are presented. The influences of the ordinance on the management of end-of-life vehicles in the Republic of Serbia on the vehicle hulks procuring, sorting generated material fractions, sorted waste allocation and sorted metals allocation decisions are thoroughly examined. The validity of the waste management strategy for the period 2010-2019 is tested. The formulated model can create optimal plans for procuring vehicle hulks, sorting generated material fractions, allocating sorted waste flows and allocating sorted metals. Obtained results are valuable for supporting the construction and/or modernisation process of a vehicle recycling system in the Republic of Serbia. © The Author(s) 2015.

Recyclable thermosetting thermal pad using silicone-based polyurethane crosslinked by Diels-Alder adduct

NASA Astrophysics Data System (ADS)

Kim, Jong-Woong; Lee, Da Hee; Jeon, Hee-Jeong; Jang, Sung Il; Cho, Hyun Min; Kim, Youngmin

2018-01-01

The recyclable silicone-based thermoset was successfully synthesized by making use of a Diels-Alder (DA) adduct as a cross-linker. The incorporation of the furan-tethered diol 1 into the polymer backbones realized the crosslinking of polymers via the DA reaction. The thermosetting polymer was dissolved in DMF after the retro DA reaction which was monitored by 1H NMR spectroscopy. Due to the retro DA reaction, polymer showed the mendable behavior when it was scratched followed by being heated. This polymer was mixed with alumina powders to fabricate the thermal pad. The thermal resistance of this pad was measured to be 0.48 K/W by a thermal transient test. The thermosetting composite was recycled via the retro DA reaction. The thermal resistance of the recycled one was similar to that of the original one.

Recycling oil: a question of quality

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jacobs, M.

If all used U.S. petroleum products could be recycled, a saving of 70,000 barrels a day could be realized on U.S. imported oil. After the sludge, water, and other contaminants are removed from used oil, a satisfactory basestock product remains. The Energy Policy and Conservation Act of 1975 directed the National Bureau of Standards to develop test procedures that can be used to establish the substantial equivalency of recycled oil with virgin oil for each potential end use. The tasks being performed by NBS on recycled oil are discussed. The researchers are also looking at the polynuclear aromatic hydrocarbons foundmore » in used and re-refined lubricating oils. It is estimated that by 1985 some 125 companies will refine nearly 20 million barrels of oil yearly with a value of $1 billion. (MCW)« less

Microstructure and Mechanical Properties of Recycled Aggregate Concrete in Seawater Environment

PubMed Central

Yue, Pengjun; Tan, Zhuoying; Guo, Zhiying

2013-01-01

This study aims to conduct research about the microstructure and basic properties of recycled aggregate concrete under seawater corrosion. Concrete specimens were fabricated and tested with different replacement percentages of 0%, 30%, and 60% after immersing in seawater for 4, 8, 12, and 16 months, respectively. The basic properties of recycled aggregate concrete (RAC) including the compressive strength, the elastic modulus, and chloride penetration depth were explicitly investigated. And the microstructure of recycled concrete aggregate (RCA) was revealed to find the seawater corrosion by using scanning electron microscope (SEM). The results showed that higher amount of the RCA means more porosity and less strength, which could lower both the compressive strength and resistance to chloride penetration. This research could be a guide in theoretical and numerical analysis for the design of RAC structures. PMID:24453830

Characterization and recycling of cadmium from waste nickel-cadmium batteries.

PubMed

Huang, Kui; Li, Jia; Xu, Zhenming

2010-11-01

A severe threat was posed due to improper and inefficient recycling of waste batteries in China. The present work considered the fundamental aspects of the recycling of cadmium from waste nickel-cadmium batteries by means of vacuum metallurgy separation in scale-up. In the first stage of this work, the characterization of waste nickel-cadmium batteries was carried out. Five types of batteries from different brands and models were selected and their components were characterized in relation to their elemental chemical composition and main phase. In the second stage of this work, the parameters affecting the recycling of cadmium by means of vacuum metallurgy separation were investigated and a L(16) (4(4)) orthogonal design was applied to optimize the parameters. With the thermodynamics theory and numerical analysis, it can be seen that the orthogonal design is an effective tool for investigating the parameters affecting the recycling of cadmium. The optimum operating parameters for the recycling of cadmium obtained by orthogonal design and verification test were 1073 K (temperature), 2.5h (heating time), 2 wt.% (the addition of carbon powder), and 30 mm (the loaded height), respectively, with recycling efficiency approaching 99.98%. The XRD and ICP-AES analyzed results show that the condensed product was characterized as metallic cadmium, and cadmium purity was 99.99% under the optimum condition. Copyright © 2010. Published by Elsevier Ltd. All rights reserved.

Constitutive apical membrane recycling in Aplysia enterocytes.

PubMed

Keeton, Robert Aaron; Runge, Steven William; Moran, William Michael

2004-11-01

In Aplysia californica enterocytes, alanine-stimulated Na+ absorption increases both apical membrane exocytosis and fractional capacitance (fCa; a measure of relative apical membrane surface area). These increases are thought to reduce membrane tension during periods of nutrient absorption that cause the enterocytes to swell osmotically. In the absence of alanine, exocytosis and fCa are constant. These findings imply equal rates of constitutive endocytosis and exocytosis and constitutive recycling of the apical plasma membrane. Thus, the purpose of this study was to confirm and determine the relative extent of constitutive apical membrane recycling in Aplysia enterocytes. Biotinylated lectins are commonly used to label plasma membranes and to investigate plasma membrane recycling. Of fourteen biotinylated lectins tested, biotinylated wheat germ agglutinin (bWGA) bound preferentially to the enterocytes apical surface. Therefore, we used bWGA, avidin D (which binds tightly to biotin), and the UV fluorophore 7-amino-4-methylcoumarin-3-acetic acid (AMCA)-conjugated avidin D to assess the extent of constitutive apical membrane recycling. A temperature-dependent (20 vs. 4 degrees C) experimental protocol employed the use of two tissues from each of five snails and resulted in a approximately 60% difference in apical surface fluorescence intensity. Because the extent of membrane recycling is proportional to the difference in surface fluorescence intensity, this difference reveals a relatively high rate of constitutive apical membrane recycling in Aplysia enterocytes.

An incentive-based source separation model for sustainable municipal solid waste management in China.

PubMed

Xu, Wanying; Zhou, Chuanbin; Lan, Yajun; Jin, Jiasheng; Cao, Aixin

2015-05-01

Municipal solid waste (MSW) management (MSWM) is most important and challenging in large urban communities. Sound community-based waste management systems normally include waste reduction and material recycling elements, often entailing the separation of recyclable materials by the residents. To increase the efficiency of source separation and recycling, an incentive-based source separation model was designed and this model was tested in 76 households in Guiyang, a city of almost three million people in southwest China. This model embraced the concepts of rewarding households for sorting organic waste, government funds for waste reduction, and introducing small recycling enterprises for promoting source separation. Results show that after one year of operation, the waste reduction rate was 87.3%, and the comprehensive net benefit under the incentive-based source separation model increased by 18.3 CNY tonne(-1) (2.4 Euros tonne(-1)), compared to that under the normal model. The stakeholder analysis (SA) shows that the centralized MSW disposal enterprises had minimum interest and may oppose the start-up of a new recycling system, while small recycling enterprises had a primary interest in promoting the incentive-based source separation model, but they had the least ability to make any change to the current recycling system. The strategies for promoting this incentive-based source separation model are also discussed in this study. © The Author(s) 2015.

Data on optimum recycle aggregate content in production of new structural concrete.

PubMed

Paul, Suvash Chandra

2017-12-01

This data presented herein are the research summary of "mechanical behavior and durability performance of concrete containing recycled concrete aggregate" (Paul, 2011) [1]. The results reported in this article relate to an important parameter of optimum content of recycle concrete aggregate (RCA) in production of new concrete for both structural and non-structural applications. For the purpose of the research various types of physical, mechanical and durability tests are performed for concrete made with different percentages of RCA. Therefore, this data set can be a great help of the readers to understand the mechanism of RCA in relates to the concrete properties.

Human subjects concerns in ground based ECLSS testing - Managing uncertainty in closely recycled systems

NASA Technical Reports Server (NTRS)

Crump, William J.; Janik, Daniel S.; Thomas, L. Dale

1990-01-01

U.S. space missions have to this point used water either made on board or carried from earth and discarded after use. For Space Station Freedom, long duration life support will include air and water recycling using a series of physical-chemical subsystems. The Environmental Control and Life Support System (ECLSS) designed for this application must be tested extensively at all stages of hardware maturity. Human test subjects are required to conduct some of these tests, and the risks associated with the use of development hardware must be addressed. Federal guidelines for protection of human subjects require careful consideration of risks and potential benefits by an Institutional Review Board (IRB) before and during testing. This paper reviews the ethical principles guiding this consideration, details the problems and uncertainties inherent in current hardware testing, and presents an incremental approach to risk assessment for ECLSS testing.

Characterization and quality assessment of recycled post-consumption poly(ethylene terephthalate) (PET).

PubMed

Masmoudi, Fatma; Fenouillot, Françoise; Mehri, Afef; Jaziri, Mohamed; Ammar, Emna

2018-06-05

In the present study, the recycled post-consumption polyethylene terephthalate (PET) flakes were investigated as possible raw materials for the production of food packaging. After heating at 220 °C for 1 h, a steaming stage was conducted as a control test to assess the quality of the product. Different samples were characterized by 1 H-NMR, FT-IR, DSC/TGA analysis, viscosity index (VI), and trace metals analysis. The results showed that the recycled post-consumed PET flakes' properties were generally conform to the standard norms of PET except the color of some flakes turned to yellow. Subsequently, a complementary study was undertaken to assess whether the material could be possibly reused for food packaging. For this purpose, rheological, thermal, and mechanical characterizations were performed. The results of the comparative study between the virgin and the recycled PET flakes concluded that the PET recycling affected the rheological properties but did not have any significant effect on their thermal and mechanical characteristics. Hence, it was deduced that the post-consumed PET flakes could be reused as a packaging material except food products.

Enhanced mechanical properties of self-polymerized polydopamine-coated recycled PLA filament used in 3D printing

NASA Astrophysics Data System (ADS)

Zhao, Xing Guan; Hwang, Kyung-Jun; Lee, Dongoh; Kim, Taemin; Kim, Namsu

2018-05-01

Dopamine readily adsorbs onto almost all kinds of surfaces and develops cohesive strength through self-polymerization; hence, aqueous solutions of dopamine can be used as adhesives. These properties were used to prevent the degradation in the mechanical properties of recycled PLA fabricated by 3D printer. The mechanical properties of 3D printed PLA play a critical role in determining its applications. To reduce the manufacturing cost as well as environmental pollutants, recycling of 3D printed materials has attracted many attentions. However, recycling of polymeric materials causes the degradation of the mechanical properties. Our study is aimed at advancing the current knowledge on the adhesion behavior of polydopamine coatings on PLA pellets used in 3D printing process. Polydopamine was synthesized by oxidative polymerization and used to coat PLA specimens. The adhesion behavior and mechanical properties of the 3D printed specimens were evaluated by tensile tests. It was found that the mechanical properties of recycled specimen with polydopamine coating have been improved. Microstructural and chemical characterization of the coated specimens was carried out using FE-SEM, FTIR, and XPS analyses.

Environmental risk related to specific processes during scrap computer recycling and disposal.

PubMed

Li, Jinhui; Shi, Pixing; Shan, Hongshan; Xie, Yijun

2012-12-01

The purpose of this work was to achieve a better understanding of the generation of toxic chemicals related to specific processes in scrap computer recycling and disposal, such as thermal recycling of printed circuit boards (PCBs) and the landfilling or dumping of cathode ray tubes (CRTs). Tube furnace pyrolysis was carried out to simulate different thermal treatment conditions for the identification of the by-products and potential environmental risk from thermal recycling ofPCBs. The Toxicity Characteristic Leaching Procedure (TCLP) and a column test were used to study the leaching characteristics of lead from waste CRT glass, which is one of the most important environmental concerns arising from the disposal of e-waste. The results indicate that more attention should be paid to the benzene series when recycling PCBs under thermal conditions, especially for workers without any personal protection equipment. The impact of immersion on the leaching of lead from CRT leaded glass was more effective than the impact of washing only by acid rain. Thus when waste leaded glass has to be stored for some reason, the storage facility should be dry.

Conceptual design for spacelab two-phase flow experiments

NASA Technical Reports Server (NTRS)

Bradshaw, R. D.; King, C. D.

1977-01-01

KC-135 aircraft tests confirmed the gravity sensitivity of two phase flow correlations. The prime component of the apparatus is a 1.5 cm dia by 90 cm fused quartz tube test section selected for visual observation. The water-cabin air system with water recycle was a clear choice for a flow regime-pressure drop test since it was used satisfactorily on KC-135 tests. Freon-11 with either overboard dump or with liquid-recycle will be used for the heat transfer test. The two experiments use common hardware. The experimental plan covers 120 data points in six hours with mass velocities from 10 to 640 kg/sec-sq m and qualities 0.01 to 0.64. The apparatus with pump, separator, storage tank and controls is mounted in a double spacelab rack. Supporting hardware, procedures, measured variables and program costs are defined.

Recycled water sources influence the bioavailability of copper to earthworms.

PubMed

Kunhikrishnan, Anitha; Bolan, Nanthi S; Naidu, Ravi; Kim, Won-Il

2013-10-15

Re-use of wastewaters can overcome shortfalls in irrigation demand and mitigate environmental pollution. However, in an untreated or partially treated state, these water sources can introduce inorganic contaminants, including heavy metals, to soils that are irrigated. In this study, earthworms (Eisenia fetida) have been used to determine copper (Cu) bioavailability in two contrasting soils irrigated with farm dairy, piggery and winery effluents. Soils spiked with varying levels of Cu (0-1,000 mg/kg) were subsequently irrigated with recycled waters and Milli-Q (MQ) water and Cu bioavailability to earthworms determined by mortality and avoidance tests. Earthworms clearly avoided high Cu soils and the effect was more pronounced in the absence than presence of recycled water irrigation. At the highest Cu concentration (1,000 mg/kg), worm mortality was 100% when irrigated with MQ-water; however, when irrigated with recycled waters, mortality decreased by 30%. Accumulation of Cu in earthworms was significantly less in the presence of recycled water and was dependent on CaCl2-extractable free Cu(2+) concentration in the soil. Here, it is evident that organic carbon in recycled waters was effective in decreasing the toxic effects of Cu on earthworms, indicating that the metal-organic complexes decreased Cu bioavailability to earthworms. Copyright © 2012 Elsevier B.V. All rights reserved.

Recycling of end-of-life reverse osmosis membranes by oxidative treatment: a technical evaluation.

PubMed

Coutinho de Paula, Eduardo; Gomes, Júlia Célia Lima; Amaral, Míriam Cristina Santos

2017-07-01

The adverse impacts caused by the disposal of thousands of tonnes per annum of reverse osmosis (RO) membranes modules have grown dramatically around the world. The objective of this study was to evaluate the technical feasibility of recycling by chemical oxidation of end-of-life RO membranes for applications in other separation processes with specifications less rigorous. The recycling technique consisted in to cause a membrane exposition with oxidant solutions in order to remove its aromatic polyamide layer and subsequent conversion to a porous membrane. The recycling technique was evaluated by water permeability and salt rejection tests before and after the oxidative treatments. Initially, membranes' chemical cleaning and pretreatment procedures were assessed. Among factors evaluated, the oxidizing agent, its concentration and pH, associated with the oxidative treatment time, showed important influence on the oxidation of the membranes. Results showed that sodium hypochlorite and potassium permanganate are efficient agents for the membrane recycling. The great increased permeability and decreased salt rejection indicated changes on membranes' selective properties. Scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), atomic force microscopy (AFM), and contact angle characterization techniques revealed marked changes on the main membranes' physical-chemical properties, such as morphology, roughness and hydrophobicity. Reuse of produced effluents and fouling tendency of recycled membranes were also evaluated.

Optimal policies for aggregate recycling from decommissioned forest roads.

PubMed

Thompson, Matthew; Sessions, John

2008-08-01

To mitigate the adverse environmental impact of forest roads, especially degradation of endangered salmonid habitat, many public and private land managers in the western United States are actively decommissioning roads where practical and affordable. Road decommissioning is associated with reduced long-term environmental impact. When decommissioning a road, it may be possible to recover some aggregate (crushed rock) from the road surface. Aggregate is used on many low volume forest roads to reduce wheel stresses transferred to the subgrade, reduce erosion, reduce maintenance costs, and improve driver comfort. Previous studies have demonstrated the potential for aggregate to be recovered and used elsewhere on the road network, at a reduced cost compared to purchasing aggregate from a quarry. This article investigates the potential for aggregate recycling to provide an economic incentive to decommission additional roads by reducing transport distance and aggregate procurement costs for other actively used roads. Decommissioning additional roads may, in turn, result in improved aquatic habitat. We present real-world examples of aggregate recycling and discuss the advantages of doing so. Further, we present mixed integer formulations to determine optimal levels of aggregate recycling under economic and environmental objectives. Tested on an example road network, incorporation of aggregate recycling demonstrates substantial cost-savings relative to a baseline scenario without recycling, increasing the likelihood of road decommissioning and reduced habitat degradation. We find that aggregate recycling can result in up to 24% in cost savings (economic objective) and up to 890% in additional length of roads decommissioned (environmental objective).

Solid state recycling of aluminium alloys via a porthole die hot extrusion process: Scaling up to production

NASA Astrophysics Data System (ADS)

Paraskevas, Dimos; Kellens, Karel; Deng, Yelin; Dewulf, Wim; Kampen, Carlos; Duflou, Joost R.

2017-10-01

Whereas industrial symbiosis has led to increased energy and resource efficiency in process industries, this concept has not yet been applied in discrete product manufacturing. Metal scrap is first conventionally recycled, for which substantial energy and resource efficiency losses have been reported. Recent research has however proven the feasibility of `meltless' recycling of light metal scrap, yielding a first glimpse of potential industrial symbiosis. Various solid state recycling techniques (such as recycling via hot extrusion or Spark Plasma Sintering) have been proposed for scrap consolidation directly into bulk products or semis by physical disruption and dispersion of the oxide surface film by imposing significant plastic and shear strain. Solid State Recycling (SSR) methods can omit substantial material losses as they bypass the metallurgical recycling step. In this context the case of direct production of bulk aluminium profiles via hot extrusion at industrial scale is demonstrated within this paper. The extrusion tests were performed directly into the production line, highlighting the scaling up potentials and the industrial relevance of this research. A significant amount of machining chips were collected, chemically cleaned and cold compacted into chip based billets with ˜80% relative density. Afterwards the scrap consolidation was achieved by imposing significant plastic and shear deformation into the material during hot extrusion through a modified 2-porthole extrusion die-set. The production process sequence along with microstructural investigations and mechanical properties comparison of the cast based profile used as reference versus the chip based profile are presented.

Sustainable operation of submerged Anammox membrane bioreactor with recycling biogas sparging for alleviating membrane fouling.

PubMed

Li, Ziyin; Xu, Xindi; Xu, Xiaochen; Yang, FengLin; Zhang, ShuShen

2015-12-01

A submerged anaerobic ammonium oxidizing (Anammox) membrane bioreactor with recycling biogas sparging for alleviating membrane fouling has been successfully operated for 100d. Based on the batch tests, a recycling biogas sparging rate at 0.2m(3)h(-1) was fixed as an ultimate value for the sustainable operation. The mixed liquor volatile suspended solid (VSS) of the inoculum for the long operation was around 3000mgL(-1). With recycling biogas sparging rate increasing stepwise from 0 to 0.2m(3)h(-1), the reactor reached an influent total nitrogen (TN) up to 1.7gL(-1), a stable TN removal efficiency of 83% and a maximum specific Anammox activity (SAA) of 0.56kg TNkg(-1) VSSd(-1). With recycling biogas sparging rate at 0.2 m(3) h(-1) (corresponding to an aeration intensity of 118m(3)m(-2)h(-1)), the membrane operation circle could prolong by around 20 times compared to that without gas sparging. Furthermore, mechanism of membrane fouling was proposed. And with recycling biogas sparging, the VSS and EPS content increasing rate in cake layer were far less than the ones without biogas sparging. The TN removal performance and sustainable membrane operation of this system showed the appealing potential of the submerged Anammox MBR with recycling biogas sparging in treating high-strength nitrogen-containing wastewaters. Copyright © 2014 Elsevier Ltd. All rights reserved.

ENVIRONMENTAL TECHNOLOGY VERIFICATION: JOINT (NSF-EPA) VERIFICATION STATEMENT AND REPORT FOR THE REMOVAL OF MERCURY FROM DENTAL OFFICE WASTEWATER, DENTAL RECYCLING OF NORTH AMERICA (DRNA) MERCURY REMOVAL UNIT (MRU). - NSF 02/01/EPAWQPC-SWP

EPA Science Inventory

Verification testing of the Dental Recycling North America (DRNA) Mercury Removal Unit (MRU) was conducted over a seven week period, at a dental office in Michigan that had three operatory rooms and two hygiene rooms. The office operated four days per week and averaged approxiam...

Torsional Shear Device for Testing the Dynamic Properties of Recycled Material

NASA Astrophysics Data System (ADS)

Gabryś, Katarzyna; Sas, Wojciech; Soból, Emil; Głuchowski, Andrzej

2016-12-01

From the viewpoint of environmental preservation and effective utilization of resources, it is beneficial and necessary to reuse wastes, for example, concrete, as the recycled aggregates for new materials. In this work, the dynamic behavior of such aggregates under low frequency torsional loading is studied. Results show that the properties of such artificial soils match with those reported in the literature for specific natural soils.

Beneficial Reuse of Produced and Flowback Water

EPA Pesticide Factsheets

Water reuse and recycling is a significant issue in the development of oil and gas shale plays in the United StatesDrilling operations – 60,000 to 650,000 gallons per wellHydraulic fracturing operations – 3 million to 5 million gallons per wellDefinition of produced water and flowback waterInteractions of water quality constituents as they relate to water reuse and recyclingTesting criteria in the laboratory and field operations

Combined Effects of Non-Conforming Fly Ash and Recycled Masonry Aggregates on Mortar Properties

PubMed Central

Torres-Gómez, Ana Isabel; Ledesma, Enrique F.; Otero, Rocio; Fernández, José Maria; Jiménez, José Ramón; de Brito, Jorge

2016-01-01

This work evaluates the effects of using non-conforming fly ash (Nc-FA) generated in a thermoelectric power plant as filler material for mortars made with natural sand (NA) and recycled sand from masonry waste (FRMA). The incorporation of powdered recycled masonry filler (R-MF) is also tested as an alternative to siliceous filler (Si-F). Three families of mortars were designed to study: the effect of replacing Si-F with Nc-FA on mortars made with NA; the effect of replacing Si-F with Nc-FA on mortars made with 50% of NA and 50% of FRMA; and the effect of replacing Si-F with R-MF on mortars made with NA and FRMA. Replacing Si-F with Nc-FA is a viable alternative that increases the mechanical strength, the workability and durability properties and decreases the shrinkage. The use of FRMA and Nc-FA improved the mechanical strength of mortars, and it slightly increased the shrinkage. The replacement of Si-F with R-MF on mortars made with FRMA is not a good alternative, because it has a negative impact on all of the properties tested. This work can help both to reduce cement and natural resources’ consumption and to increase the recycling rate of Nc-FA and FRMA. PMID:28773849

Combined Effects of Non-Conforming Fly Ash and Recycled Masonry Aggregates on Mortar Properties.

PubMed

Torres-Gómez, Ana Isabel; Ledesma, Enrique F; Otero, Rocio; Fernández, José Maria; Jiménez, José Ramón; de Brito, Jorge

2016-08-25

This work evaluates the effects of using non-conforming fly ash (Nc-FA) generated in a thermoelectric power plant as filler material for mortars made with natural sand (NA) and recycled sand from masonry waste (FRMA). The incorporation of powdered recycled masonry filler (R-MF) is also tested as an alternative to siliceous filler (Si-F). Three families of mortars were designed to study: the effect of replacing Si-F with Nc-FA on mortars made with NA; the effect of replacing Si-F with Nc-FA on mortars made with 50% of NA and 50% of FRMA; and the effect of replacing Si-F with R-MF on mortars made with NA and FRMA. Replacing Si-F with Nc-FA is a viable alternative that increases the mechanical strength, the workability and durability properties and decreases the shrinkage. The use of FRMA and Nc-FA improved the mechanical strength of mortars, and it slightly increased the shrinkage. The replacement of Si-F with R-MF on mortars made with FRMA is not a good alternative, because it has a negative impact on all of the properties tested. This work can help both to reduce cement and natural resources' consumption and to increase the recycling rate of Nc-FA and FRMA.

Capture of Tritium Released from Cladding in the Zirconium Recycle Process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Spencer, Barry B.; Walker, T. B.; Bruffey, S. H.

2016-08-31

Zirconium may be recovered from the Zircaloy® cladding of used nuclear fuel (UNF) for recycle or to reduce the quantities of high-level waste destined for a geologic repository. Recovery of zirconium using a chlorination process is currently under development at the Oak Ridge National Laboratory. The approach is to treat the cladding with chlorine gas to convert the zirconium in the alloy (~98 wt % of the alloy mass) to zirconium tetrachloride. A significant fraction of the tritium (0–96%) produced in nuclear fuel during irradiation may be found in zirconium-based cladding and could be released from the cladding when themore » solid matrix is destroyed by the chlorination reaction. To prevent uncontrolled release of radioactive tritium to other parts of the plant or to the environment, a method to recover the tritium may be required. The focus of this effort was to (1) identify potential methods for the recovery of tritium from the off-gas of the zirconium recycle process, (2) perform scoping tests on selected recovery methods using nonradioactive gas simulants, and (3) select a process design appropriate for testing on radioactive gas streams generated by the engineering-scale zirconium recycle demonstrations on radioactive used cladding.« less

Capture of Tritium Released from Cladding in the Zirconium Recycle Process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Spencer, Barry B.; Walker, T. B.; Bruffey, Stephanie H.

2016-08-31

This report is issued as the first revision to FCRD-MRWFD-2016-000297. Zirconium may be recovered from the Zircaloy® cladding of used nuclear fuel (UNF) for recycle or to reduce the quantities of high-level waste destined for a geologic repository. Recovery of zirconium using a chlorination process is currently under development at the Oak Ridge National Laboratory. The approach is to treat the cladding with chlorine gas to convert the zirconium in the alloy (~98 wt % of the alloy mass) to zirconium tetrachloride. A significant fraction of the tritium (0–96%) produced in nuclear fuel during irradiation may be found in zirconium-basedmore » cladding and could be released from the cladding when the solid matrix is destroyed by the chlorination reaction. To prevent uncontrolled release of radioactive tritium to other parts of the plant or to the environment, a method to recover the tritium may be required. The focus of this effort was to (1) identify potential methods for the recovery of tritium from the off-gas of the zirconium recycle process, (2) perform scoping tests on selected recovery methods using non-radioactive gas simulants, and (3) select a process design appropriate for testing on radioactive gas streams generated by the engineering-scale zirconium recycle demonstrations on radioactive used cladding.« less

Neuronal ceroid lipofuscinoses (NCL)

MedlinePlus

... problems with the brain's ability to remove and recycle proteins. Lipofuscinoses are inherited as autosomal recessive traits. ... is recommended if your family has a known history of NCL. Prenatal tests, or a test called ...

Inactive Mineral Filler as a Stiffness Modulus Regulator in Foamed Bitumen-Modified Recycled Base Layers

NASA Astrophysics Data System (ADS)

Buczyński, Przemyslaw; Iwański, Marek

2017-10-01

The article presents the results of a cold recycled mix test with a foam bitumen including the addition of the inactive mineral filler as a dust of basalt. Basalt dust was derived from dedusting system by extraction of aggregates in the mine. Assessment of the impact of a basalt dust on the properties of a recycled base layer was carried out in terms of the amount of mineral filler (basalt) in the composition of the mineral mixture. This experiment involved a dosing of mineral filler in range from 5 to 20% with steps of 7.5% in the mineral mixture composition. The foamed bitumen was performed at optimum foaming process settings (ie. bitumen temperature, air pressure) and at 2.5% of the water content. The amount of a hydraulic binder as a Portland cement was 2.0%. The evaluation of rheological properties allowed to determine whether the addition of inactive mineral fillers can act as a stiffness modulus controller in the recycled base layer. The analysis of the rheological properties of a recycled base layer in terms of the amount of inactive fillers was performed in accordance with given standard EN 12697-26 Annex D. The study was carried out according to the direct tension-compression test methodology on cylindrical samples. The sample was subjected to the oscillatory sinusoidal strain ε0 < 25με. Studies carried out at a specific temperature set-points: - 7°C, 5°C, 13°C, 25°C and 40°C and at the frequency 0.1 Hz, 0.3 Hz, 1 Hz, 3 Hz, 10 Hz and 20 Hz. The obtained results allow to conclude that the use of an inactive filler can reduce the stiffness of an appropriate designed mixes of the cold recycled foundation. In addition, the analysis of the relation E‧-E″ showed a similar behaviour of a recycled base, regardless of the amount of inactive fillers in the mix composition, at high temperatures/high frequency of induced load.

Evaluation of drinking water treatment combined filter backwash water recycling technology based on comet and micronucleus assay.

PubMed

Chen, Ting; Xu, Yongpeng; Liu, Zhiquan; Zhu, Shijun; Shi, Wenxin; Cui, Fuyi

2016-04-01

Based on the fact that recycling of combined filter backwash water (CFBW) directly to drinking water treatment plants (WTP) is considered to be a feasible method to enhance pollutant removal efficiency, we were motivated to evaluate the genotoxicity of water samples from two pilot-scale drinking water treatment systems, one with recycling of combined backwash water, the other one with a conventional process. An integrated approach of the comet and micronucleus (MN) assays was used with zebrafish (Danio rerio) to investigate the water genotoxicity in this study. The total organic carbon (TOC), dissolved organic carbon (DOC), and trihalomethane formation potential (THMFP), of the recycling process were lower than that of the conventional process. All the results showed that there was no statistically significant difference (P>0.05) between the conventional and recycling processes, and indicated that the genotoxicity of water samples from the recycling process did not accumulate in 15 day continuous recycling trial. It was worth noting that there was correlation between the concentrations of TOC, DOC, UV254, and THMFPs in water and the DNA damage score, with corresponding R(2) values of 0.68, 0.63, 0.28, and 0.64. Nevertheless, both DNA strand breaks and MN frequency of all water samples after disinfection were higher than that of water samples from the two treatment units, which meant that the disinfection by-products (DBPs) formed by disinfection could increase the DNA damage. Both the comet and MN tests suggest that the recycling process did not increase the genotoxicity risk, compared to the traditional process. Copyright © 2015. Published by Elsevier B.V.

Recycling of asbestos tailings used as reinforcing fillers in polypropylene based composites.

PubMed

Zhai, Wensi; Wang, Yao; Deng, Yuan; Gao, Hongli; Lin, Zhen; Li, Mao

2014-04-15

In this work, asbestos tailings were recycled and used as reinforcing fillers to enhance the mechanical properties of polypropylene (PP). A silane coupling agent was used to chemically modify the asbestos tailings to increase the compatibility between asbestos tailings and polypropylene matrix. Both raw and chemically treated asbestos tailings with different loading levels (from 3 to 30 wt%) were utilized to fabricate composites. Mechanical properties of these composites have been investigated by dynamic mechanical analysis, tensile test and notched impact test. Results showed that hybridization of asbestos tailings in the composites enhanced the mechanical properties of neat PP evidently, and treated asbestos tailings/PP composites yielded even better mechanical properties compared with those of raw asbestos tailings/PP composites. This recycling method of asbestos tailings not only reduces disposal costs and avoids secondary pollution but also produces a new PP-based composite material with enhanced mechanical properties. Copyright © 2014 Elsevier B.V. All rights reserved.

Trends in biomarkers, biotic indices, and fish population size revealed contrasting long-term effects of recycled water on the ecological status of a Mediterranean river.

PubMed

Colin, Nicole; Maceda-Veiga, Alberto; Monroy, Mario; Ortega-Ribera, Martí; Llorente, Mireia; de Sostoa, Adolfo

2017-11-01

Recycled water is important for maintaining river flow in semi-arid regions. However, it has ecological risk, as suggested by comparison of habitat and white and red blood cell count in two wild fish species (Barbus meridionalis and Squalius laietanus) before and after an input of recycled water in Ripoll River (NE Spain) in 2009. Due to the lack of normal ranges for blood variables in wild fish, we surveyed seasonally the same river reaches in 2013 to test if blood alterations from 2009 compromised the viability of the fish populations. By examining other indicators of river health in baseline and polluted sites (fish abundance, mass-length relationships, and community indices in fish, diatoms and invertebrates), we tested for the superior utility of blood tests in biomonitoring. The comparison of water quality and scores of diatoms and invertebrate indices between polluted and reference sites showed that polluted sites improved from 2009 to 2013. The abundance of B. meridionalis also increased in polluted sites, but that of S. laietanus declined in 2013 compared to 2009. These results contrast with results of blood analyses in 2009, which suggested that B. meridionalis was more seriously affected by pollution than S. laietanus. The fish index did not reveal the risk of recycled water to fish health, whereas fish mass-length relationships suggested that S. laietanus individuals in 2013 had a better body condition in polluted than in reference sites. Given that the two fish species had opposite results in reference sites, and that the physical habitat was more suitable for B. meridionalis in polluted sites in 2013 than was for S. laietanus, trends in population size are not only explained by pollution. The role of phenology is suggested by peaks in blood disorders during the breeding season. However, more long-term studies combining indicators of river health at the individual and community scales are needed to fully assess the ecological risk of recycled water in this river. These studies will also help to develop blood tests as reliable health indicators in wild fish populations. Copyright © 2017 Elsevier Inc. All rights reserved.

Use of steel fibres recovered from waste tyres as reinforcement in concrete: pull-out behaviour, compressive and flexural strength.

PubMed

Aiello, M A; Leuzzi, F; Centonze, G; Maffezzoli, A

2009-06-01

The increasing amount of waste tyres worldwide makes the disposition of tyres a relevant problem to be solved. In the last years over three million tons of waste tyres were generated in the EU states [ETRA, 2006. Tyre Technology International - Trends in Tyre Recycling. http://www.etra-eu.org]; most of them were disposed into landfills. Since the European Union Landfill Directive (EU Landfill, 1999) aims to significantly reduce the landfill disposal of waste tyres, the development of new markets for the tyres becomes fundamental. Recently some research has been devoted to the use of granulated rubber and steel fibres recovered from waste tyres in concrete. In particular, the concrete obtained by adding recycled steel fibres evidenced a satisfactory improvement of the fragile matrix, mostly in terms of toughness and post-cracking behaviour. As a consequence RSFRC (recycled steel fibres reinforced concrete) appears a promising candidate for both structural and non-structural applications. Within this context a research project was undertaken at the University of Salento (Italy) aiming to investigate the mechanical behaviour of concrete reinforced with RSF (recycled steel fibres) recovered from waste tyres by a mechanical process. In the present paper results obtained by the experimental work performed up to now are reported. In order to evaluate the concrete-fibres bond characteristics and to determine the critical fibre length, pull-out tests were initially carried out. Furthermore compressive strength of concrete was evaluated for different volume ratios of added RSF and flexural tests were performed to analyze the post-cracking behaviour of RSFRC. For comparison purposes, samples reinforced with industrial steel fibres (ISF) were also considered. Satisfactory results were obtained regarding the bond between recycled steel fibres and concrete; on the other hand compressive strength of concrete seems unaffected by the presence of fibres despite their irregular geometric properties. Finally, flexural tests furnished in some cases results comparable to those obtained when using ISF as concerns the post-cracking behaviour.

Waste Treatment Technology Process Development Plan For Hanford Waste Treatment Plant Low Activity Waste Recycle

DOE Office of Scientific and Technical Information (OSTI.GOV)

McCabe, Daniel J.; Wilmarth, William R.; Nash, Charles A.

2013-08-29

The purpose of this Process Development Plan is to summarize the objectives and plans for the technology development activities for an alternative path for disposition of the recycle stream that will be generated in the Hanford Waste Treatment Plant Low Activity Waste (LAW) vitrification facility (LAW Recycle). This plan covers the first phase of the development activities. The baseline plan for disposition of this stream is to recycle it to the WTP Pretreatment Facility, where it will be concentrated by evaporation and returned to the LAW vitrification facility. Because this stream contains components that are volatile at melter temperatures andmore » are also problematic for the glass waste form, they accumulate in the Recycle stream, exacerbating their impact on the number of LAW glass containers. Approximately 32% of the sodium in Supplemental LAW comes from glass formers used to make the extra glass to dilute the halides to acceptable concentrations in the LAW glass, and reducing the halides in the Recycle is a key component of this work. Additionally, under possible scenarios where the LAW vitrification facility commences operation prior to the WTP Pretreatment facility, this stream does not have a proven disposition path, and resolving this gap becomes vitally important. This task seeks to examine the impact of potential future disposition of this stream in the Hanford tank farms, and to develop a process that will remove radionuclides from this stream and allow its diversion to another disposition path, greatly decreasing the LAW vitrification mission duration and quantity of glass waste. The origin of this LAW Recycle stream will be from the Submerged Bed Scrubber (SBS) and the Wet Electrostatic Precipitator (WESP) from the LAW melter off-gas system. The stream is expected to be a dilute salt solution with near neutral pH, and will likely contain some insoluble solids from melter carryover or precipitates of scrubbed components (e.g. carbonates). The soluble components are mostly sodium and ammonium salts of nitrate, chloride, and fluoride. This stream has not been generated yet, and will not be available until the WTP begins operation, causing uncertainty in its composition, particularly the radionuclide content. This plan will provide an estimate of the likely composition and the basis for it, assess likely treatment technologies, identify potential disposition paths, establish target treatment limits, and recommend the testing needed to show feasibility. Two primary disposition options are proposed for investigation, one is concentration for storage in the tank farms, and the other is treatment prior to disposition in the Effluent Treatment Facility. One of the radionuclides that is volatile and expected to be in high concentration in this LAW Recycle stream is Technetium-99 ({sup 99}Tc), a long-lived radionuclide with a half-life of 210,000 years. Technetium will not be removed from the aqueous waste in the Hanford Waste Treatment and Immobilization Plant (WTP), and will primarily end up immobilized in the LAW glass, which will be disposed in the Integrated Disposal Facility (IDF). Because {sup 99}Tc has a very long half-life and is highly mobile, it is the largest dose contributor to the Performance Assessment (PA) of the IDF. Other radionuclides that are also expected to be in appreciable concentration in the LAW Recycle are {sup 129}I, {sup 90}Sr, {sup 137}Cs, and {sup 241}Am. The concentrations of these radionuclides in this stream will be much lower than in the LAW, but they will still be higher than limits for some of the other disposition pathways currently available. Although the baseline process will recycle this stream to the Pretreatment Facility, if the LAW facility begins operation first, this stream will not have a disposition path internal to WTP. One potential solution is to return the stream to the tank farms where it can be evaporated in the 242-A evaporator, or perhaps deploy an auxiliary evaporator to concentrate it prior to return to the tank farms. In either case, testing is needed to evaluate if this stream is compatible with the evaporator and the other wastes in the tank farm. It should be noted that prior experience in evaporation of another melter off-gas stream, the Recycle Stream at the SRS Defense Waste Processing Facility, unexpectedly caused deleterious impacts on evaporator scaling and formation of aluminosilicate solids before controls were implemented. The compatibility of this stream with other wastes and components in the tank farms has not been fully investigated, whether it is sent for storage in AW-102 in preparation for evaporation in 242-A evaporator, or if it is pre-concentrated in an auxiliary evaporator. This stream is expected to be unusual because it will be very high in corrosive species that are volatile in the melter (chloride, fluoride, sulfur), will have high ammonia, and will contain carryover particulates of glass-former chemicals. These species have potential to cause corrosion, precipitation, flammable gases, and scale in the tank farm system. Testing is needed to demonstrate acceptable conditions and limits for these compounds in wastes sent to the tank farms. Alternate disposition of this LAW Recycle stream could beneficially impact WTP, and may also remove a sizeable fraction of the 99Tc from the source term at the IDF. The alternative radionuclide removal process envisioned for this stream parallels the Actinide Removal Process that has been successfully used at SRS for several years. In that process, Monosodium Titanate (MST) is added to the tank waste to adsorb 90Sr and actinides, and then the MST and radionuclides are removed by filtration. The process proposed for investigation for the Hanford WTP LAW Recycle stream would similarly add MST to remove 90Sr and actinides, along with other absorbents or precipitating agents for the remaining radionuclides. These include inorganic reducing agents for Tc, and zeolites for 137Cs. After treatment, disposition of the decontaminated Recycle stream may be suitable for the Effluent Treatment Facility, where it could be evaporated and solidified. The contaminated slurry stream containing the absorbents and radionuclides will be preliminarily characterized in this phase of the program to evaluate disposal options, and disposition routes will be tested in the next phase. The testing described herein will aid in selection of the best disposal pathway. Several research tasks have been identified that are needed for this initial phase: imulant formulation- Concentration of Recycle to reduce storage volume; Blending of concentrated Recycle with tank waste; Sorption of radionuclides; Precipitation of radionuclides. After this initial phase of testing, additional tasks are expected to be identified for development. These tasks likely include evaluation and testing of applicable solid-liquid separation technologies, slurry rheology measurements, composition variability testing and evaluations, corrosion and erosion testing, slurry storage and immobilization investigations, and decontaminated Recycle evaporation and solidification. Although there are a number of unknown parameters listed in the technical details of the concepts described here, many of these parameters have precedence and do not generally require fundamental new scientific breakthroughs. Many of the materials and processes described are already used in radioactive applications in the DOE complex, or have been tested previously in comparable conditions. Some of these materials and equipment are already used in High Level Waste applications, which are much more complex and aggressive conditions than the LAW Recycle stream. In some cases, the unknown parameters are simply extensions of already studied conditions, such as tank waste corrosion chemistry. The list of testing needs at first appears daunting, but virtually all have been done before, although there are potential issues with compatibility with this unique waste stream. It is anticipated that the challenge will be more in integrating the system and complying with process limitations than in developing entirely new technologies. Several assumptions have been made in this document about the acceptability of radionuclide decontamination and potential waste forms for disposal. These assumptions have been used to define acceptability criteria for feasibility studies on removal. These limits are not intended to define regulatory or facility limits, but rather provide a starting point for evaluating various technologies.« less

Technical specifications for mechanical recycling of agricultural plastic waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

Briassoulis, D., E-mail: briassou@aua.gr; Hiskakis, M.; Babou, E.

Highlights: • Technical specifications for agricultural plastic wastes (APWs) recycling proposed. • Specifications are the base for best economical and environmental APW valorisation. • Analysis of APW reveals inherent characteristics and constraints of APW streams. • Thorough survey on mechanical recycling processes and industry as it applies to APW. • Specifications for APW recycling tested, adjusted and verified through pilot trials. - Abstract: Technical specifications appropriate for the recycling of agricultural plastic wastes (APWs), widely accepted by the recycling industry were developed. The specifications establish quality standards to be met by the agricultural plastics producers, users and the agricultural plasticmore » waste management chain. They constitute the base for the best economical and environmental valorisation of the APW. The analysis of the APW streams conducted across Europe in the framework of the European project “LabelAgriWaste” revealed the inherent characteristics of the APW streams and the inherent constraints (technical or economical) of the APW. The APW stream properties related to its recycling potential and measured during pilot trials are presented and a subsequent universally accepted simplified and expanded list of APW recycling technical specifications is proposed and justified. The list includes two sets of specifications, applied to two different quality categories of recyclable APW: one for pellet production process (“Quality I”) and another one for plastic profile production process (“Quality II”). Parameters that are taken into consideration in the specifications include the APW physical characteristics, contamination, composition and degradation. The proposed specifications are focused on polyethylene based APW that represents the vast majority of the APW stream. However, the specifications can be adjusted to cover also APW of different materials (e.g. PP or PVC) that are found in very small quantities in protected cultivations in Europe. The adoption of the proposed specifications could transform this waste stream into a labelled commodity traded freely in the market and will constitute the base for the best economical and environmental valorisation of the APW.« less

Rehabilitation reliability of the road pavement structure with recycled base course with foamed bitumen

NASA Astrophysics Data System (ADS)

Buczyński, P.

2018-05-01

This article presents a new approach to reliability assessment of the road structure in which the base layer will be constructed in the process of cold deep recycling with foamed bitumen. In order to properly assess the reliability of the structure with the recycled base, it is necessary to determine the distribution of stress and strain in typical pavement layer systems. The true stress and strain values were established for particular structural layers using the complex modulus (E*) determined based on the master curves. The complex modulus was determined by the direct tension-compression test on cylindrical specimens (DTC-CY) at five temperatures (-7°C, 5°C, 13°C, 25°C, 40°C) and six loading times (0.1 Hz, 0.3 Hz, 1 Hz, 3 Hz, 10 Hz, 20 Hz) in accordance with EN 12697-26 in the linear viscoelasticity (LVE) range for small strains ranging from 25 to 50 με. The master curves of the complex modulus were constructed using the Richards model for the mixtures typically incorporated in structural layers, i.e., SMA11, AC16W, AC22P and MCAS. The values of the modulus characterizing particular layers were determined with temperature distribution in the structure taken into account, when the surface temperature was 40°C. The stress distribution was established for those calculation models. The stress values were used to evaluate the fatigue life under controlled stress conditions (IT-FT). This evaluation, with the controlled stress corresponding to that in the structure, facilitated the quality assessment of the rehabilitated recycled base course. Results showed that the recycled base mixtures having the indirect tensile strength (ITSDRY) similar to the stress in the structure under analysis needed an additional fatigue life evaluation in the indirect tensile test ITT. This approach to the recycled base quality assessment will allow eliminating the damage induced by overloading.

Programme on the recyclability of food-packaging materials with respect to food safety considerations: polyethylene terephthalate (PET), paper and board, and plastics covered by functional barriers.

PubMed

Franz, R

2002-01-01

Stimulated by new ecology-driven European and national regulations, news routes of recycling waste appear on the market. Since food packages represent a large percentage of the plastics consumption and since they have a short lifetime, an important approach consists in making new packages from post-consumer used packages. On the other hand, food-packaging regulations in Europe require that packaging materials must be safe. Therefore, potential mass transfer (migration) of harmful recycling-related substances to the food must be excluded and test methods to ensure the safety-in-use of recycled materials for food packaging are needled. As a consequence of this situation, a European research project FAIR-CT98-4318, with the acronym 'Recyclability', was initiated. The project consists of three sections each focusing on a different class of recycled materials: polyethylene terephthalate (PET), paper and board, and plastics covered by functional barriers. The project consortium consists of 28 project members from 11 EU countries. In addition, the project is during its lifetime in discussion with the US Food and Drug Administrations (FDA) to consider also US FDA regulatory viewpoints and to aim, as a consequence, to harmonizable conclusions and recommendations. The paper introduces the project and presents an overview of the project work progress.

Bench scale experiments for the remediation of Hanford Waste Treatment Plant low activity waste melter off-gas condensate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Taylor-Pashow, Kathryn M.L.; Poirier, Michael; McCabe, Daniel J.

The Low Activity Waste (LAW) vitrification facility at the Hanford Waste Treatment and Immobilization Plant (WTP) will generate an aqueous condensate recycle stream (LAW Off-Gas Condensate) from the off-gas system. The plan for disposition of this stream during baseline operations is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility again. The primary reason to recycle this stream is so that the semi-volatile 99Tc isotope eventually becomes incorporated into the glass. This stream also contains non-radioactive salt components that are problematic in the melter,more » so diversion of this stream to another process would eliminate recycling of these salts and would enable simplified operation of the LAW melter and the Pretreatment Facilities. This diversion from recycling this stream within WTP would have the effect of decreasing the LAW vitrification mission duration and quantity of glass waste. The concept being tested here involves removing the 99Tc so that the decontaminated aqueous stream, with the problematic salts, can be disposed elsewhere.« less

Investigation of variable compositions on the removal of technetium from Hanford Waste Treatment Plant low activity waste melter off-gas condensate simulant

DOE Office of Scientific and Technical Information (OSTI.GOV)

Taylor-Pashow, Kathryn M. L.; McCabe, Daniel J.; Pareizs, John M.

The Low Activity Waste (LAW) vitrification facility at the Hanford Waste Treatment and Immobilization Plant (WTP) will generate an aqueous condensate recycle stream (LAW Off-Gas Condensate) from the offgas system. The plan for disposition of this stream during baseline operations is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility again. The primary reason to recycle this stream is so that the semi-volatile 99Tc isotope eventually becomes incorporated into the glass. This stream also contains non-radioactive salt components that are problematic in the melter,more » so diversion of this stream to another process would eliminate recycling of these salts and would enable simplified operation of the LAW melter and the Pretreatment Facilities. This diversion from recycling this stream within WTP would have the effect of decreasing the LAW vitrification mission duration and quantity of glass waste. The concept being tested here involves removing the 99Tc so that the decontaminated aqueous stream, with the problematic salts, can be disposed elsewhere.« less

Chemical recycling of scrap composites

NASA Technical Reports Server (NTRS)

Allred, Ronald E.; Salas, Richard M.

1994-01-01

There are no well-developed technologies for recycling composite materials other than grinding to produce fillers. New approaches are needed to reclaim these valuable resources. Chemical or tertiary recycling, conversion of polymers into low molecular weight hydrocarbons for reuse as chemicals or fuels, is emerging as the most practical means for obtaining value from waste plastics and composites. Adherent Technologies is exploring a low-temperature catalytic process for recycling plastics and composites. Laboratory results show that all types of plastics, thermosets as well as thermoplastics, can be converted in high yields to valuable hydrocarbon products. This novel catalytic process runs at 200 C, conversion times are rapid, the process is closed and, thus, nonpolluting, and no highly toxic gas or liquid products have been observed so no negative environmental impact will result from its implementation. Tests on reclamation of composite materials show that epoxy, imide, and engineering thermoplastic matrices can be converted to low molecular weight hydrocarbons leaving behind the reinforcing fibers for reuse as composite reinforcements in secondary, lower-performance applications. Chemical recycling is also a means to dispose of sensitive or classified organic materials without incineration and provides a means to eliminate or reduce mixed hazardous wastes containing organic materials.

Membrane process treatment for greywater recycling: investigations on direct tubular nanofiltration.

PubMed

Hourlier, F; Massé, A; Jaouen, P; Lakel, A; Gérente, C; Faur, C; Cloirec, P Le

2010-01-01

On-site greywater recycling and reuse is one of the main ways to reduce potable water requirement in urban areas. Direct membrane filtration is a promising technology to recycle greywater on-site. This study aimed at selecting a tubular nanofiltration (NF) membrane and its operating conditions in order to treat and reuse greywater in buildings. To do so, a synthetic greywater (SGW) was reconstituted in order to conduct experiments on a reproducible effluent. Then, three PCI NF membranes (AFC30, AFC40 and AFC80) having distinct molecular weight cut-offs were tested to recycle this SGW with a constant concentration at 25°C at two different transmembrane pressures (20 and 35 bar). The best results were obtained with AFC80 at 35 bar: the flux was close to 50 L m⁻²  h⁻¹, retentions of 95% for chemical oxygen demand and anionic surfactants were observed, and no Enterococcus were detected in the permeate. The performances of AFC80 were also evaluated on a real greywater: fluxes and retentions were similar to those observed on SGW. These results demonstrate the effectiveness of direct nanofiltration to recycle and reuse greywater.

Multifunctional Single-Phase Photocatalysts: Extended Near Infrared Photoactivity and Reliable Magnetic Recyclability

NASA Astrophysics Data System (ADS)

Li, Xiaoning; Zhu, Zhu; Li, Feng; Huang, Yan; Hu, Xiang; Huang, Haoliang; Peng, Ranran; Zhai, Xiaofang; Fu, Zhengping; Lu, Yalin

2015-10-01

A practical photocatalyst should be able to integrate together various functions including the extended solar conversion, a feasible and economic recyclability, and above the room temperature operation potential, et al., in order to fulfill the spreading application needs in nowadays. In this report, a multifunctional single-phase photocatalyst which possesses a high photoactivity extended into the near infrared region, an easy magnetic recyclability and the high temperature stability was developed by doping Co into a new layer-structured Bi7Fe3Ti3O21 material. Light absorption and photocatalytic activity of the resulted Bi7Fe3-xCoxTi3O21 photocatalyst were extended to the long wavelength as far as 800 nm. Its strong ferromagnetism above the room temperature enables the nanopowders fully recyclable in viscous solutions simply with a magnet bar in an experimental demonstration. Furthermore, such photoactivity and magnetic recyclability were heavily tested under high-temperature and high-viscosity conditions, which was intended to simulate the actual industrial environments. This work brings the bright light to a full availability of a new multifunctional photocatalyst, via integrating the much enhanced ferromagnetic, ferroelectric, optoelectronic properties, most importantly, into a single-phase structure.

Influence of the grade on the variability of the mechanical properties of polypropylene waste.

PubMed

Jmal, Hamdi; Bahlouli, Nadia; Wagner-Kocher, Christiane; Leray, Dimitri; Ruch, Frédéric; Munsch, Jean-Nicolas; Nardin, Michel

2018-05-01

The prior properties of recycled polypropylene depend on the origin of waste deposits and its chemical constituents. To obtain specific properties with a predefine melt flow index of polypropylene, the suppliers of polymer introduce additives and fillers. However, the addition of additives and/or fillers can modify strongly the mechanical behaviour of recycled polypropylene. To understand the impact of the additives and fillers on the quasi-static mechanical behaviour, we consider, in this study, three different recycled polypropylenes with three different melt flow index obtained from different waste deposits. The chemical constituents of the additives and filler contents of the recycled polypropylenes are determined through thermo-physico-chemical analysis. Tensile and bending tests performed at different strain rates allow identifying the mechanical properties such as the elastic modulus, the yield stress, the maximum stress, and the failure mechanisms. The results obtained are compared with non-recycled polypropylene and with few researches to explain the combined effect of additives. Finally, a post-mortem analysis of the samples was carried out to make the link between the obtained mechanical properties and microstructure. Copyright © 2018 Elsevier Ltd. All rights reserved.

Migration kinetics of mineral oil hydrocarbons from recycled paperboard to dry food: monitoring of two real cases.

PubMed

Lorenzini, R; Biedermann, M; Grob, K; Garbini, D; Barbanera, M; Braschi, I

2013-01-01

Mineral oil hydrocarbons present in printing inks and recycled paper migrate from paper-based food packaging to foods primarily through the gas phase. Migration from two commercial products packed in recycled paperboard, i.e. muesli and egg pasta, was monitored up to the end of their shelf life (1 year) to study the influence of time, storage conditions, food packaging structure and temperature. Mineral oil saturated and aromatic hydrocarbons (MOSH and MOAH, respectively), and diisopropyl naphthalenes (DIPN) were monitored using online HPLC-GC/FID. Storage conditions were: free standing, shelved, and packed in transport boxes of corrugated board, to represent domestic, supermarket and warehouse storage, respectively. Migration to food whose packs were kept in transport boxes was the highest, especially after prolonged storage, followed by shelved and free-standing packs. Tested temperatures were representative of refrigeration, room temperature, storage in summer months and accelerated migration testing. Migration was strongly influenced by temperature: for egg pasta directly packed in paperboard, around 30 mg kg⁻¹ of MOSH migrated in 8 months at 20°C, but in only 1 week at 40°C. Muesli was contained into an internal polyethylene bag, which firstly adsorbed hydrocarbons and later released them partly towards the food. Differently, the external polypropylene bag, containing pasta and recycled paper tray, strongly limited the migration towards the atmosphere and gave rise to the highest level of food contamination. Tests at increased temperatures not only accelerated migration, but also widened the migration of hydrocarbons to higher molecular masses, highlighting thus a difficult interpretation of data from accelerated simulation.

Mechanical Behavior of Recycled Aggregate Concrete-Filled Steel Tubular Columns before and after Fire.

PubMed

Liu, Wenchao; Cao, Wanlin; Zhang, Jianwei; Wang, Ruwei; Ren, Lele

2017-03-09

Recycled aggregate concrete (RAC) is an environmentally friendly building material. This paper investigates the mechanical behavior of recycled aggregate concrete filled steel tube (RACFST) columns exposed to fire. Two groups of 12 columns were designed and tested, under axial compression, before and after fire, to evaluate the degradation of bearing capacity due to fire exposure. Six specimens were subjected to axial compression tests at room temperature and the other six specimens were subjected to axial compression tests after a fire exposure. The main parameters of the specimens include the wall thickness of the steel tube (steel content) and the type of concrete materials. Several parameters as obtained from the experimental results were compared and analyzed, including the load-bearing capacity, deformation capacity, and failure characteristics of the specimens. Meanwhile, rate of loss of bearing capacity of specimens exposed to fire were calculated based on the standards EC4 and CECS28:90. The results show that concrete material has a large influence on the rate of loss of bearing capacity in the case of a relatively lower steel ratio. While steel content has little effect on the rate of loss of bearing capacity of concrete-filled steel tube (CFST) columns after fire, it has a relatively large influence on the loss rate of bearing capacity of the RACFST columns. The loss of bearing capacity of the specimens from the experiment is more serious than that from the calculation. As the calculated values are less conservative, particular attention should be given to the application of recycled aggregate concrete in actual structures.

Mechanical Behavior of Recycled Aggregate Concrete-Filled Steel Tubular Columns before and after Fire

PubMed Central

Liu, Wenchao; Cao, Wanlin; Zhang, Jianwei; Wang, Ruwei; Ren, Lele

2017-01-01

Recycled aggregate concrete (RAC) is an environmentally friendly building material. This paper investigates the mechanical behavior of recycled aggregate concrete filled steel tube (RACFST) columns exposed to fire. Two groups of 12 columns were designed and tested, under axial compression, before and after fire, to evaluate the degradation of bearing capacity due to fire exposure. Six specimens were subjected to axial compression tests at room temperature and the other six specimens were subjected to axial compression tests after a fire exposure. The main parameters of the specimens include the wall thickness of the steel tube (steel content) and the type of concrete materials. Several parameters as obtained from the experimental results were compared and analyzed, including the load-bearing capacity, deformation capacity, and failure characteristics of the specimens. Meanwhile, rate of loss of bearing capacity of specimens exposed to fire were calculated based on the standards EC4 and CECS28:90. The results show that concrete material has a large influence on the rate of loss of bearing capacity in the case of a relatively lower steel ratio. While steel content has little effect on the rate of loss of bearing capacity of concrete-filled steel tube (CFST) columns after fire, it has a relatively large influence on the loss rate of bearing capacity of the RACFST columns. The loss of bearing capacity of the specimens from the experiment is more serious than that from the calculation. As the calculated values are less conservative, particular attention should be given to the application of recycled aggregate concrete in actual structures. PMID:28772634

Remote fabrication and irradiation test of recycled nuclear fuel prepared by the oxidation and reduction of spent oxide fuel

NASA Astrophysics Data System (ADS)

Jin Ryu, Ho; Chan Song, Kee; Il Park, Geun; Won Lee, Jung; Seung Yang, Myung

2005-02-01

A direct dry recycling process was developed in order to reuse spent pressurized light water reactor (LWR) nuclear fuel in CANDU reactors without the separation of sensitive nuclear materials such as plutonium. The benefits of the dry recycling process are the saving of uranium resources and the reduction of spent fuel accumulation as well as a higher proliferation resistance. In the process of direct dry recycling, fuel pellets separated from spent LWR fuel rods are oxidized from UO2 to U3O8 at 500 °C in an air atmosphere and reduced into UO2 at 700 °C in a hydrogen atmosphere, which is called OREOX (oxidation and reduction of oxide fuel). The pellets are pulverized during the oxidation and reduction processes due to the phase transformation between cubic UO2 and orthorhombic U3O8. Using the oxide powder prepared from the OREOX process, the compaction and sintering processes are performed in a remote manner in a shielded hot cell due to the high radioactivity of the spent fuel. Most of the fission gas and volatile fission products are removed during the OREOX and sintering processes. The mini-elements fabricated by the direct dry recycling process are irradiated in the HANARO research reactor for the performance evaluation of the recycled fuel pellets. Post-irradiation examination of the irradiated fuel showed that microstructural evolution and fission gas release behavior of the dry-recycled fuel were similar to high burnup UO2 fuel.

Organoclay nanocomposites of post-industrial waste poly(butylene terephthalate) from automotive parts.

PubMed

Quispe, Noe B; Fernandes, Elizabeth G; Zanata, Fernanda; Bartoli, Julio R; Souza, Diego H S; Ito, Edson N

2015-10-01

Polymeric nanocomposites are novel materials of huge interest owing to their favourable cost/performance ratio with low amount of nanofillers, improved thermal resistance, flame retardancy and mechanical properties in relation to their matrices. In this work, composites based on post-industrial waste or primary recycled poly(butylene terephthalate) and 5 wt.% of organic modified montmorillonite clays were melt compounded using a twin-screw extruder. A 2(2) factorial experimental design was used to study the compounding and processing variables: Organic modified montmorillonite with one or two hydrogenated tallow (initial basal spacing) and screw speed of the extruder. X-ray diffraction and transmission electron microscopy suggest that a partial exfoliation of the organoclay in the recycled poly(butylene terephthalate) matrix was achieved for organic modified montmorillonite with lower initial basal spacing. On the other hand, formulations containing organic modified montmorillonite with higher initial basal spacing showed only intercalated structure. The recycled poly(butylene terephthalate)-organic modified montmorillonite nanocomposites did not drip flaming material during burning tests. Storage of dynamic-mechanical, tensile and flexural moduli of the recycled poly(butylene terephthalate)-organic modified montmorillonite were improved when compared with both virgin and recycled poly(butylene terephthalate)s, mainly for nanocomposites formulated at a lower initial basal spacing organoclay. This could be related to a better diffusion of polymer into organic modified montmorillonite layers compared with the higher initial basal spacing organoclay. The improvements on the physical properties of recycled poly(butylene terephthalate) showed the feasibility to add value to primary recycled engineering thermoplastics with a very small amount of organic modified montmorillonite. © The Author(s) 2015.

Plant growth and mineral recycle trade-offs in different scenarios for a CELSS. [Closed Ecological Life Support System

NASA Technical Reports Server (NTRS)

Ballou, E. V.; Wydeven, T.; Spitze, L. A.

1982-01-01

Data for hydroponic plant growth in a manned system test is combined with nutritional recommendations to suport trade-off calculations for closed and partially closed life support system scenarios. Published data are used as guidelines for the masses of mineral nutrients needed for higher plant production. The results of calculations based on various scenarios are presented for various combinations of plant growth chamber utilization and fraction of mineral recycle. Estimates are made of the masses of material needed to meet human nutritional requirements in the various scenarios. It appears that food production from a plant growth chamber with mineral recycle is favorable to reduction of the total launch weight in missions exceeding 3 years.

Aspects of the tribological behaviour of powders recycled from rapid steel treated sub-zero

NASA Astrophysics Data System (ADS)

Radu, S.; Ciobanu, M.

2017-02-01

The recycling of high-alloyed steels represents a significant opportunity in Powder Metallurgy as it permits the use of raw materials with relatively low prices compared to the conventional methods. Recycling can be achieved by two methods: from spraying debris resulted from worn cutting tools and processes obtained from processing chip drilling and re-sharpening of tools. The research aims to confirm that wastes from rapid steels can become, by the successive processing, metal powders that can thereafter be used for cutting tools of lathe type removable plate. After pressing and sintering the recycling powder, cylindrical samples were obtained that were subsequently applied a subcritical annealing. Wear tests conducted on a tribometer type TRB-01-02541 confirmed that their wear resistance is superior to the same samples that were sintered, hardened and tempered in oil. This paper was accepted for publication in Proceedings after double peer reviewing process but was not presented at the Conference ROTRIB’16.

Recycling of Kinesin-1 Motors by Diffusion after Transport

PubMed Central

Blasius, T. Lynne; Reed, Nathan; Slepchenko, Boris M.; Verhey, Kristen J.

2013-01-01

Kinesin motors drive the long-distance anterograde transport of cellular components along microtubule tracks. Kinesin-dependent transport plays a critical role in neurogenesis and neuronal function due to the large distance separating the soma and nerve terminal. The fate of kinesin motors after delivery of their cargoes is unknown but has been postulated to involve degradation at the nerve terminal, recycling via retrograde motors, and/or recycling via diffusion. We set out to test these models concerning the fate of kinesin-1 motors after completion of transport in neuronal cells. We find that kinesin-1 motors are neither degraded nor returned by retrograde motors. By combining mathematical modeling and experimental analysis, we propose a model in which the distribution and recycling of kinesin-1 motors fits a “loose bucket brigade” where individual motors alter between periods of active transport and free diffusion within neuronal processes. These results suggest that individual kinesin-1 motors are utilized for multiple rounds of transport. PMID:24098765

Transesterification of Waste Activated Sludge for Biosolids Reduction and Biodiesel Production.

PubMed

Maeng, Min Ho; Cha, Daniel K

2018-02-01

  Transesterification of waste activated sludge (WAS) was evaluated as a cost-effective technique to reduce excess biosolids and recover biodiesel feedstock from activated sludge treatment processes. A laboratory-scale sequencing batch reactor (SBR) was operated with recycling transesterification-treated WAS back to the aeration basin. Seventy percent recycling of WAS resulted in a 48% reduction of excess biosolids in comparison with a conventional SBR, which was operated in parallel as the control SBR. Biodiesel recovery of 8.0% (dried weight basis) was achieved at an optimum transesterification condition using acidic methanol and xylene as cosolvent. Average effluent soluble chemical oxygen demand (COD) and total suspended solids (TSS) concentrations from the test SBR and control SBR were comparable, indicating that the recycling of transesterification-treated WAS did not have detrimental effect on the effluent quality. This study demonstrated that transesterification and recycling of WAS may be a feasible technique for reducing excess biosolids, while producing valuable biodiesel feedstock from the activated sludge process.

Application of RANS Simulations for Contact Time Predictions in Turbulent Reactor Tanks for Water Purification Process

NASA Astrophysics Data System (ADS)

Nickles, Cassandra; Goodman, Matthew; Saez, Jose; Issakhanian, Emin

2016-11-01

California's current drought has renewed public interest in recycled water from Water Reclamation Plants (WRPs). It is critical that the recycled water meets public health standards. This project consists of simulating the transport of an instantaneous conservative tracer through the WRP chlorine contact tanks. Local recycled water regulations stipulate a minimum 90-minute modal contact time during disinfection at peak dry weather design flow. In-situ testing is extremely difficult given flowrate dependence on real world sewage line supply and recycled water demand. Given as-built drawings and operation parameters, the chlorine contact tanks are modeled to simulate extreme situations, which may not meet regulatory standards. The turbulent flow solutions are used as the basis to model the transport of a turbulently diffusing conservative tracer added instantaneously to the inlet of the reactors. This tracer simulates the transport through advection and dispersion of chlorine in the WRPs. Previous work validated the models against experimental data. The current work shows the predictive value of the simulations.

Acoustic emission monitoring of recycled aggregate concrete under bending

NASA Astrophysics Data System (ADS)

Tsoumani, A. A.; Barkoula, N.-M.; Matikas, T. E.

2015-03-01

The amount of construction and demolition waste has increased considerably over the last few years, making desirable the reuse of this waste in the concrete industry. In the present study concrete specimens are subjected at the age of 28 days to four-point bending with concurrent monitoring of their acoustic emission (AE) activity. Several concrete mixtures prepared using recycled aggregates at various percentages of the total coarse aggregate and also a reference mix using natural aggregates, were included to investigate their influence of the recycled aggregates on the load bearing capacity, as well as on the fracture mechanisms. The results reveal that for low levels of substitution the influence of using recycled aggregates on the flexural strength is negligible while higher levels of substitution lead into its deterioration. The total AE activity, as well as the AE signals emitted during failure, was related to flexural strength. The results obtained during test processing were found to be in agreement with visual observation.

Mechanical Properties of Recycled Concrete in Marine Environment

PubMed Central

Wang, Jianxiu; Huang, Tianrong; Liu, Xiaotian; Wu, Pengcheng; Guo, Zhiying

2013-01-01

Experimental work was carried out to develop information about mechanical properties of recycled concrete (RC) in marine environment. By using the seawater and dry-wet circulation to simulate the marine environment, specimens of RC were tested with different replacement percentages of 0%, 30%, and 60% after immersing in seawater for 4, 8, 12, and 16 months, respectively. Based on the analysis of the stress-strain curves (SSCs) and compressive strength, it is revealed that RC' peak value and elastic modulus decreased with the increase of replacement percentage and corroding time in marine environment. And the failure of recycled concrete was speeded up with more obvious cracks and larger angles of 65° to 85° in the surface when compared with normal concrete. Finally, the grey model (GM) with equal time intervals was constructed to investigate the law of compressive strength of recycled concrete in marine environment, and it is found that the GM is accurate and feasible for the prediction of RC compressive strength in marine environment. PMID:23766707

Lead paste recycling based on conversion into battery grade oxides. Electrochemical tests and industrial production of new batteries

NASA Astrophysics Data System (ADS)

Fusillo, G.; Rosestolato, D.; Scura, F.; Cattarin, S.; Mattarozzi, L.; Guerriero, P.; Gambirasi, A.; Brianese, N.; Staiti, P.; Guerriero, R.; La Sala, G.

2018-03-01

We present the preparation and characterization of pure lead monoxide obtained through recycling of the lead paste recovered from exhausted lead acid batteries. The recycling is based on a hydrometallurgical procedure reported in a STC Patent, that includes simple chemical operations (desulphurisation, leaching, precipitation, filtration) and a final thermal conversion. Materials obtained by treatment at 600 °C consist predominantly of β-PbO. The electrochemical behaviour of Positive Active Mass (PAM) prepared from different materials (or mixtures) is then investigated and compared. An optimized oxide material, obtained by prolonged (8 h) thermal treatment at 600 °C, consists of pure β-PbO and appears suitable for preparation of battery elements, alone or in mixture with a small fraction (10%-30%) of traditional industrial leady oxide. The resulting battery performances are similar to those obtained from pure leady oxide. In comparison with traditional recycling processes, the proposed method guarantees lower energy consumption, limited environmental impact and reduced operating risk for industry workers.

Effect of oil palm empty fruit bunches fibers reinforced polymer recycled

NASA Astrophysics Data System (ADS)

Hermawan, B.; Nikmatin, S.; Sudaryanto; Alatas, H.; Sukaryo, S. G.

2017-07-01

The aim of this research is to process the OPEFB to become fiber with various sizes which will be used as a filler of polymer matrix recycled acrylonitrile butadiene styrene (ABS). Molecular analysis and mechanical test have been done to understand the influence of fiber size toward material capability to receive outer deformation. Single screw extruder formed a biocomposites granular continued with injection moulding to shaped test pieces. Maleic anhydride was added as coupling agent between filler and matrix. Filler concentration were 10 and 20% in fiber size respectively with constant additif. Two kind of fiber glass (10%) were used as comparator. In order to analyze the results of the mechanical test Fisher least significant difference (LSD) in ANOVA method was performed (-with α=0,05-).

Composite Material from By-products and Its Properties

NASA Astrophysics Data System (ADS)

Šeps, K.; Broukalová, I.; Vodička, J.

2017-09-01

The paper shows an example of utilization of specific textile admixture - fluffs of torn textiles from waste cars in production of composite with aggregate consisting entirely of unsorted recycled concrete. The admixture in the mixture of recycled concrete and cement binder fills the pores and voids in composite. The elaborated composite has working title STEREDconcrete. In the article, basic mechanical-physical properties of the composite are presented also the fire resistance of STEREDconcrete, which was determined in tests.

PLA recycling by hydrolysis at high temperature

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cristina, Annesini Maria; Rosaria, Augelletti; Sara, Frattari, E-mail: sara.frattari@uniroma1.it

In this work the process of PLA hydrolysis at high temperature was studied, in order to evaluate the possibility of chemical recycling of this polymer bio-based. In particular, the possibility to obtain the monomer of lactic acid from PLA degradation was investigated. The results of some preliminary tests, performed in a laboratory batch reactor at high temperature, are presented: the experimental results show that the complete degradation of PLA can be obtained in relatively low reaction times.

Diffusibility Enhancement of Rejuvenator by Epoxidized Soybean Oil and Its Influence on the Performance of Recycled Hot Mix Asphalt Mixtures

PubMed Central

Kuang, Dongliang; Jiao, Yuan; Ye, Zhou; Lu, Zaihong; Chen, Huaxin; Yu, Jianying; liu, Ning

2018-01-01

Epoxidized soybean oil (ESO) was employed as a novel penetrant cooperating with a conventional rejuvenator (CR) for the recycling of reclaimed asphalt pavement (RAP). The influence of ESO on the diffusibility and the regenerating effects of CR on RAP were investigated. The diffusibility testing result shows that the diffusibility of CR is enhanced by the addition of ESO because the epoxy group in ESO can facilitate asphaltene dispersion due to its high polarity, which simultaneously reduces the viscosity and improves the fluidity of aged bitumen so as to allow diffusion of the rejuvenator into the aged bitumen. Road performance testing of a recycled hot mix asphalt mixture (RHMA) indicates that the fatigue and cracking resistance properties as well as the water stability of RHMA containing CR can be improved by the addition of ESO due to the diffusibility enhancement of CR, which boosts the regenerating effect of CR on aged bitumen in RAP. The fatigue and cracking resistance properties as well as the water stability of the recycled hot mix asphalt mixture containing CR with 7 wt % ESO approximate those of the hot mix asphalt mixture composed of the same virgin aggregates and bitumen. Taking into account the rutting resistance decline versus the addition of ESO, the content of ESO should not exceed 7 wt % of the conventional rejuvenator. PMID:29783675

Diffusibility Enhancement of Rejuvenator by Epoxidized Soybean Oil and Its Influence on the Performance of Recycled Hot Mix Asphalt Mixtures.

PubMed

Kuang, Dongliang; Jiao, Yuan; Ye, Zhou; Lu, Zaihong; Chen, Huaxin; Yu, Jianying; Liu, Ning

2018-05-18

Epoxidized soybean oil (ESO) was employed as a novel penetrant cooperating with a conventional rejuvenator (CR) for the recycling of reclaimed asphalt pavement (RAP). The influence of ESO on the diffusibility and the regenerating effects of CR on RAP were investigated. The diffusibility testing result shows that the diffusibility of CR is enhanced by the addition of ESO because the epoxy group in ESO can facilitate asphaltene dispersion due to its high polarity, which simultaneously reduces the viscosity and improves the fluidity of aged bitumen so as to allow diffusion of the rejuvenator into the aged bitumen. Road performance testing of a recycled hot mix asphalt mixture (RHMA) indicates that the fatigue and cracking resistance properties as well as the water stability of RHMA containing CR can be improved by the addition of ESO due to the diffusibility enhancement of CR, which boosts the regenerating effect of CR on aged bitumen in RAP. The fatigue and cracking resistance properties as well as the water stability of the recycled hot mix asphalt mixture containing CR with 7 wt % ESO approximate those of the hot mix asphalt mixture composed of the same virgin aggregates and bitumen. Taking into account the rutting resistance decline versus the addition of ESO, the content of ESO should not exceed 7 wt % of the conventional rejuvenator.

Latex improvement of recycled asphalt pavement

NASA Astrophysics Data System (ADS)

Drennon, C.

1982-08-01

The performance of a single unmodified milled recycled asphalt concrete was compared to milled asphalt concrete modified by addition of three types of rubber latex. Latex was added at 2, 3, 5, and 8 percent latex by weight of asphalt in the asphalt concrete. Lattices used were a styrene butadiene (SBR), a natural rubber (NR), an acrylonitrile butadiene (NBR), and four varieties of out of specification SBR lattices. Marshall tests, while indecisive, showed a modest improvement in properties of SBR and NR added material at 3 and 5 percent latex. Addition of NBR latex caused deterioration in Marshall stability and flow over that of control. Repeated load tests were run using the indirect tensile test, analyzed by the VESYS program, which computes life of pavements. Repeated load tests showed improvement in asphalt concrete life when 3 and 5 percent SBR was added. Improvement was also shown by the out of specification SBR.

Risk assessment by percolation leaching tests of extensive green roofs with fine fraction of mixed recycled aggregates from construction and demolition waste.

PubMed

López-Uceda, Antonio; Galvín, Adela P; Ayuso, Jesús; Jiménez, José Ramón; Vanwalleghem, Tom; Peña, Adolfo

2018-03-19

Extensive green roofs are urban construction systems that provide thermal regulation and sound proofing for the buildings involved, in addition to providing an urban heat island mitigation or water retention. On the other hand, policies towards reduction of energy consumption, a circular economy and sustainability are core in the European Union. Motivated by this, an experimental study was carried out to evaluate the environmental risk assessment according to release levels of polluting elements on leachates of different green roof substrate mixtures based on recycled aggregates from construction and demolition waste through (i) the performance in laboratory of two procedures: compliance and percolation tests and (ii) an upscaled experimental leaching test for long-term on-site prediction. Four plots were built on a building roof and covered with autochthonous Mediterranean plants in Córdoba, South of Spain. As growing substrate, four mixtures were used of a commercial growing substrate with different proportions of a fine mixed recycled aggregate ranging from 0 to 75% by volume. The results show that these mixtures were classified as non-hazardous materials according to legal limits of the Landfill Directive 2003/33/CE. The release levels registered in extensive green roofs were lower compared to the laboratory test data. This shows how laboratory conditions can overestimate the potential pollutant effect of these materials compared to actual conditions.

Validation of laboratory-scale recycling test method of paper PSA label products

Treesearch

Carl Houtman; Karen Scallon; Richard Oldack

2008-01-01

Starting with test methods and a specification developed by the U.S. Postal Service (USPS) Environmentally Benign Pressure Sensitive Adhesive Postage Stamp Program, a laboratory-scale test method and a specification were developed and validated for pressure-sensitive adhesive labels, By comparing results from this new test method and pilot-scale tests, which have been...

Bond efficacy of recycled orthodontic brackets: A comparative in vitro evaluation of two methods.

PubMed

Shetty, Vikram; Shekatkar, Yash; Kumbhat, Neesu; Gautam, G; Karbelkar, Shalan; Vandekar, Meghna

2015-01-01

Recycling of orthodontic brackets in developing orthodontic economies is an extremely common procedure. Bonding protocols and reliability of these brackets is, however, questionable, and still the subject of research. The aim was to evaluate and compare the shear bond strength of brackets recycled with sandblasting and silicoating. Ninety extracted human premolars were bonded with 0.022" SS brackets (American Orthodontics, Sheboygan USA) and then debonded. The debonded brackets were divided into three groups of 30 each. Group I: Sandblasting with 50-μm aluminum oxide (control group) Group II: Sandblasting with 50-μm aluminum oxide followed by metal primer application Group III: Silicoating with 30-μm Cojet sand followed by silane application and rebonded with Transbond XT. The sandblasted brackets and silicoated brackets were viewed under the scanning electron microscope, immediately after surface conditioning before rebonding. The shear bond strength with each group was tested. One-way analysis of variance, post-hoc Scheffe multiple comparison tests. The results showed that sandblasting created more irregularities and deeper erosions while silica coating created superficial irregularities and shallow erosions.

Chemical and ecotoxicological analyses of sediments and elutriates of contaminated rivers due to e-waste recycling activities using a diverse battery of bioassays.

PubMed

Wang, F; Leung, A O W; Wu, S C; Yang, M S; Wong, M H

2009-07-01

A multi-trophic, multi-exposure phase assessment approach was applied to characterize the toxicity of sediments collected from two rivers in Guiyu, China, an e-waste recycling centre. Elutriate toxicity tests (bacterium Vibrio fischeri and microalga Selenastrum capricornutum) and whole sediment toxicity test (crustacean Heterocypris incongruens) showed that most sediments exhibited acute toxicity, due to elevated heavy metals and PAHs levels, and low pH caused by uncontrolled acid discharge. The survival rates of crustaceans were negatively (p < 0.05) correlated with total PAHs in sediments (411-1755 mg kg(-1)); EC50s of V. fischeri on the elutriates were significantly correlated with elutriate pH (p < 0.01). Significant (p < 0.05) correlations between the induction of hepatic metallothionein in tilapia (Oreochromis mossambicus) and metal concentrations (Cu, Zn, Pb) in sediments were also observed, when fish were fed with diets containing sediment. The results showed that uncontrolled e-waste recycling activities may bring adverse effects to local aquatic ecosystem.

Microbiological test results of the environmental control and life support systems vapors compression distillation subsystem recycle tank components following various pretreatment protocols

NASA Technical Reports Server (NTRS)

Huff, Tim

1993-01-01

Microbiological samples were collected from the recycle tank of the vapor compression distillation (VCD) subsystem of the water recovery test at NASA MSFC following a 68-day run. The recycle tank collects rejected urine brine that was pretreated with a commercially available oxidant (Oxone) and sulfuric acid and pumps it back to the processing component of the VCD. Samples collected included a water sample and two swab samples, one from the particulate filter surface and a second from material floating on the surface of the water. No bacteria were recovered from the water sample. Both swab samples contained a spore-forming bacterium, Bacillus insolitus. A filamentous fungus was isolated from the floating material. Approximately 1 month after the pretreatment chemicals were changed to sodium hypochlorite and sulfuric acid, a swab of the particulate filter was again analyzed for microbial content. One fungus was isolated, and spore-forming bacteria were observed. These results indicate the inability of these pretreatments to inhibit surface attachment. The implications of the presence of these organisms are discussed.

Biomarkers of mercury exposure at a mercury recycling facility in Ukraine.

PubMed

Gibb, Herman Jones; Kozlov, Kostj; Buckley, Jessie Poulin; Centeno, Jose; Jurgenson, Vera; Kolker, Allan; Conko, Kathryn; Landa, Edward; Panov, Boris; Panov, Yuri; Xu, Hanna

2008-08-01

This study evaluates biomarkers of occupational mercury exposure among workers at a mercury recycling operation in Gorlovka, Ukraine. The 29 study participants were divided into three occupational categories for analysis: (1) those who worked in the mercury recycling operation (Group A, n = 8), (2) those who worked at the facility but not in the yard where the recycling was done (Group B, n = 14), and (3) those who did not work at the facility (Group C, n = 7). Urine, blood, hair, and nail samples were collected from the participants, and a questionnaire was administered to obtain data on age, gender, occupational history, smoking, alcohol consumption, fish consumption, tattoos, dental amalgams, home heating system, education, source of drinking water, and family employment in the former mercury mine/smelter located on the site of the recycling facility. Each factor was tested in a univariate regression with total mercury in urine, blood, hair, and nails. Median biomarker concentrations were 4.04 microg/g-Cr (urine), 2.58 microg/L (blood), 3.95 microg/g (hair), and 1.16 microg/g (nails). Occupational category was significantly correlated (p < 0.001) with both blood and urinary mercury concentrations but not with hair or nail mercury. Four individuals had urinary mercury concentrations in a range previously found to be associated with subtle neurological and subjective symptoms (e.g., fatigue, loss of appetite, irritability), and one worker had a urinary mercury concentration in a range associated with a high probability of neurological effects and proteinuria. Comparison of results by occupational category found that workers directly involved with the recycling operation had the highest blood and urinary mercury levels. Those who worked at the facility but were not directly involved with the recycling operation had higher levels than those who did not work at the facility.

Stormwater harvesting for irrigation purposes: an investigation of chemical quality of water recycled in pervious pavement system.

PubMed

Nnadi, Ernest O; Newman, Alan P; Coupe, Stephen J; Mbanaso, Fredrick U

2015-01-01

Most available water resources in the world are used for agricultural irrigation. Whilst this level of water use is expected to increase due to rising world population and land use, available water resources are expected to become limited due to climate change and uneven rainfall distribution. Recycled stormwater has the potential to be used as an alternative source of irrigation water and part of sustainable water management strategy. This paper reports on a study to investigate whether a sustainable urban drainage system (SUDS) technique, known as the pervious pavements system (PPS) has the capability to recycle water that meets irrigation water quality standard. Furthermore, the experiment provided information on the impact of hydrocarbon (which was applied to simulate oil dripping from parked vehicles onto PPS), leaching of nutrients from different layers of the PPS and effects of nutrients (applied to enhance bioremediation) on the stormwater recycling efficiency of the PPS. A weekly dose of 6.23 × 10(-3) L of lubricating oil and single dose of 17.06 g of polymer coated controlled-release fertilizer granules were applied to the series of 710 mm × 360 mm model pervious pavement structure except the controls. Rainfall intensity of 7.4 mm/h was applied to the test models at the rate of 3 events per week. Analysis of the recycled water showed that PPS has the capability to recycle stormwater to a quality that meets the chemical standards for use in agricultural irrigation irrespective of the type of sub-base used. There is a potential benefit of nutrient availability in recycled water for plants, but care should be taken not to dispose of this water in natural water courses as it might result in eutrophication problems. Copyright © 2014 Elsevier Ltd. All rights reserved.

Comparative environmental assessment of natural and recycled aggregate concrete.

PubMed

Marinković, S; Radonjanin, V; Malešev, M; Ignjatović, I

2010-11-01

Constant and rapid increase in construction and demolition (C&D) waste generation and consumption of natural aggregate for concrete production became one of the biggest environmental problems in the construction industry. Recycling of C&D waste represents one way to convert a waste product into a resource but the environment benefits through energy consumption, emissions and fallouts reductions are not certain. The main purpose of this study is to determine the potentials of recycled aggregate concrete (concrete made with recycled concrete aggregate) for structural applications and to compare the environmental impact of the production of two types of ready-mixed concrete: natural aggregate concrete (NAC) made entirely with river aggregate and recycled aggregate concrete (RAC) made with natural fine and recycled coarse aggregate. Based on the analysis of up-to-date experimental evidence, including own tests results, it is concluded that utilization of RAC for low-to-middle strength structural concrete and non-aggressive exposure conditions is technically feasible. The Life Cycle Assessment (LCA) is performed for raw material extraction and material production part of the concrete life cycle including transport. Assessment is based on local LCI data and on typical conditions in Serbia. Results of this specific case study show that impacts of aggregate and cement production phases are slightly larger for RAC than for NAC but the total environmental impacts depend on the natural and recycled aggregates transport distances and on transport types. Limit natural aggregate transport distances above which the environmental impacts of RAC can be equal or even lower than the impacts of NAC are calculated for the specific case study. Copyright © 2010 Elsevier Ltd. All rights reserved.

Studying the rapid bioconversion of lignocellulosic sugars into ethanol using high cell density fermentations with cell recycle

PubMed Central

2014-01-01

Background The Rapid Bioconversion with Integrated recycle Technology (RaBIT) process reduces capital costs, processing times, and biocatalyst cost for biochemical conversion of cellulosic biomass to biofuels by reducing total bioprocessing time (enzymatic hydrolysis plus fermentation) to 48 h, increasing biofuel productivity (g/L/h) twofold, and recycling biocatalysts (enzymes and microbes) to the next cycle. To achieve these results, RaBIT utilizes 24-h high cell density fermentations along with cell recycling to solve the slow/incomplete xylose fermentation issue, which is critical for lignocellulosic biofuel fermentations. Previous studies utilizing similar fermentation conditions showed a decrease in xylose consumption when recycling cells into the next fermentation cycle. Eliminating this decrease is critical for RaBIT process effectiveness for high cycle counts. Results Nine different engineered microbial strains (including Saccharomyces cerevisiae strains, Scheffersomyces (Pichia) stipitis strains, Zymomonas mobilis 8b, and Escherichia coli KO11) were tested under RaBIT platform fermentations to determine their suitability for this platform. Fermentation conditions were then optimized for S. cerevisiae GLBRCY128. Three different nutrient sources (corn steep liquor, yeast extract, and wheat germ) were evaluated to improve xylose consumption by recycled cells. Capacitance readings were used to accurately measure viable cell mass profiles over five cycles. Conclusion The results showed that not all strains are capable of effectively performing the RaBIT process. Acceptable performance is largely correlated to the specific xylose consumption rate. Corn steep liquor was found to reduce the deleterious impacts of cell recycle and improve specific xylose consumption rates. The viable cell mass profiles indicated that reduction in specific xylose consumption rate, not a drop in viable cell mass, was the main cause for decreasing xylose consumption. PMID:24847379

In-Space Recycler Technology Demonstration

NASA Technical Reports Server (NTRS)

Hoyt, Rob; Werkheiser, NIKI; Kim, Tony

2016-01-01

In 2014, a 3D printer was installed and used successfully on the International Space Station (ISS), creating the first additively manufactured part in space. While additive manufacturing is a game changing technology for exploration missions, the process still requires raw feedstock material to fabricate parts. Without a recycling capability, a large supply of feedstock would need to be stored onboard, which negates the logistical benefits of these capabilities. Tethers Unlimited, Inc. (TUI), received a Small Business Innovation Research (SBIR) award to design and build the first In-space Recycler for demonstration aboard the ISS in 2017. To fully test this technology in microgravity, parts will be 3D printed, recycled into reusable filament, and then reprinted into new parts. Recycling scrap into printer filament is quite challenging in that a recycler must be able to handle a large variety of possible scrap configurations and densities. New challenges include: dealing with inevitable contamination of the scrap material, minimizing damage to the molecular structure of the plastic during reprocessing, managing a larger volume of hot liquid plastic, and exercising greater control over the cooling/resolidification of the material. TUI has developed an architecture that addresses these challenges by combining standard, proven technologies with novel, patented processes developed through this effort. Results show that the filament diameter achieved is more consistent than commercial filament, with only minimal degradation of material properties over recycling steps. In May 2016, TUI completed fabrication of a flight prototype, which will ultimately progress to the demonstration unit for the ISS as a testbed for future exploration missions. This capability will provide significant cost savings by reducing the launch mass and volume required for printer feedstock as well as reduce waste that must be stored or disposed.

Recycling of Reinforced Plastics

NASA Astrophysics Data System (ADS)

Adams, R. D.; Collins, Andrew; Cooper, Duncan; Wingfield-Digby, Mark; Watts-Farmer, Archibald; Laurence, Anna; Patel, Kayur; Stevens, Mark; Watkins, Rhodri

2014-02-01

This work has shown is that it is possible to recycle continuous and short fibre reinforced thermosetting resins while keeping almost the whole of the original material, both fibres and matrix, within the recyclate. By splitting, crushing hot or cold, and hot forming, it is possible to create a recyclable material, which we designate a Remat, which can then be used to remanufacture other shapes, examples of plates and tubes being demonstrated. Not only can remanufacturing be done, but it has been shown that over 50 % of the original mechanical properties, such as the E modulus, tensile strength, and interlaminar shear strength, can be retained. Four different forms of composite were investigated, a random mat Glass Fibre Reinforced Plastic (GFRP) bathroom component and boat hull, woven glass and carbon fibre cloth impregnated with an epoxy resin, and unidirectional carbon fibre pre-preg. One of the main factors found to affect composite recyclability was the type of resin matrix used in the composite. Thermoset resins tested were shown to have a temperature range around the Glass Transition Temperature (Tg) where they exhibit ductile behaviour, hence aiding reforming of the material. The high-grade carbon fibre prepreg was found to be less easy to recycle than the woven of random fibre laminates. One method of remanufacturing was by heating the Remat to above its glass transition temperature, bending it to shape, and then cooling it. However, unless precautions are taken, the geometric form may revert. This does not happen with the crushed material.

Preliminary experimental results of gas recycling subsystems except carbon dioxide concentration

NASA Astrophysics Data System (ADS)

Otsuji, K.; Sawada, T.; Satoh, S.; Kanda, S.; Matsumura, H.; Kondo, S.; Otsubo, K.

Oxygen concentration and separation is an essential factor for air recycling in a CELSS. Furthermore, if the value of the plant assimilatory quotient is not coincident with that of the animal respiratory quotient, the recovery of O2 from the concentrated CO2 through chemical methods will become necessary to balance the gas contents in a CELSS. Therefore, oxygen concentration and separation equipment using Salcomine and O2 recovery equipment, such as Sabatier and Bosch reactors, were experimentally developed and tested.

A hybrid froth flotation-filtration system as a pretreatment for oil sands tailings pond recycle water management: Bench- and pilot-scale studies.

PubMed

Loganathan, Kavithaa; Bromley, David; Chelme-Ayala, Pamela; Gamal El-Din, Mohamed

2015-09-15

Through sustainable water management, oil sands companies are working to reduce their reliance on fresh water by minimizing the amount of water required for their operations and by recycling water from tailings ponds. This study was the first pilot-scale testing of a hybrid technology consisting of froth flotation combined with filtration through precoated submerged stainless steel membranes used to treat recycle water from an oil sands facility. The results indicated that the most important factor affecting the performance of the hybrid system was the influent water quality. Any rise in the levels of suspended solids or total organic carbon of the feed water resulted in changes of chemical consumption rates, flux rates, and operating cycle durations. The selections of chemical type and dosing rates were critical in achieving optimal performance. In particular, the froth application rate heavily affected the overall recovery of the hybrid system as well as the performance of the flotation process. Optimum surfactant usage to generate froth (per liter of treated water) was 0.25 mL/L at approximately 2000 NTU of influent turbidity and 0.015 mL/L at approximately 200 NTU of influent turbidity. At the tested conditions, the optimal coagulant dose was 80 mg/L (as Al) at approximately 2000 NTU of influent turbidity and <40 mg/L (as Al) at approximately 200 NTU of influent turbidity. Precoat loading per unit membrane surface area tested during the pilot study was approximately 30 g/m(2). The results of this study indicated that this hybrid technology can potentially be considered as a pre-treatment step for reverse osmosis treatment of recycle water. Copyright © 2015 Elsevier Ltd. All rights reserved.

Recycling of petroleum-contaminated sand.

PubMed

Taha, R; Ba-Omar, M; Pillay, A E; Roos, G; al-Hamdi, A

2001-08-01

The environmental impact of using petroleum-contaminated sand (PCS) as a substitute in asphalt paving mixtures was examined. An appreciable component of PCS is oily sludge, which is found as the dregs in oil storage tanks and is also produced as a result of oil spills on clean sand. The current method for the disposal of oily sludge is land farming. However, this method has not been successful as an oil content of < 1% w/w is required, and difficulty was encountered in reaching this target. The reuse of the sludge in asphalt paving mixtures was therefore considered as an alternative. Standard tests and environmental studies were conducted to establish the integrity of the materials containing the recycled sludge. These included physical and chemical characterization of the sludge itself, and an assessment of the mechanical properties of materials containing 0%, 5%, 22% and 50% oily sludge. The blended mixtures were subjected to special tests, such as Marshall testing and the determination of stability and flow properties. The experimental results indicated that mixtures containing up to 22% oily sludge could meet the necessary criteria for a specific asphalt concrete wearing course or bituminous base course. To maximize the assay from the recycled material, the environmental assessment was restricted to the 50% oily sludge mixture. Leachates associated with this particular mixture were assayed for total organic residue and certain hazardous metal contaminants. The results revealed that the organics were negligible, and the concentrations of the metals were not significant. Thus, no adverse environmental impact should be anticipated from the use of the recycled product. Our research showed that the disposal of oily sludge in asphalt paving mixtures could possibly yield considerable savings per tonne of asphalt concrete, and concurrently minimize any direct impact on the environment.

Leaching assessment of concrete made of recycled coarse aggregate: physical and environmental characterisation of aggregates and hardened concrete.

PubMed

Galvín, A P; Agrela, F; Ayuso, J; Beltrán, M G; Barbudo, A

2014-09-01

Each year, millions of tonnes of waste are generated worldwide, partially through the construction and demolition of buildings. Recycling the resulting waste could reduce the amount of materials that need to be manufactured. Accordingly, the present work has analysed the potential reuse of construction waste in concrete manufacturing by replacing the natural aggregate with recycled concrete coarse aggregate. However, incorporating alternative materials in concrete manufacturing may increase the pollutant potential of the product, presenting an environmental risk via ground water contamination. The present work has tested two types of concrete batches that were manufactured with different replacement percentages. The experimental procedure analyses not only the effect of the portion of recycled aggregate on the physical properties of concrete but also on the leaching behaviour as indicative of the contamination degree. Thus, parameters such as slump, density, porosity and absorption of hardened concrete, were studied. Leaching behaviour was evaluated based on the availability test performed to three aggregates (raw materials of the concrete batches) and on the diffusion test performed to all concrete. From an environmental point of view, the question of whether the cumulative amount of heavy metals that are released by diffusion reaches the availability threshold was answered. The analysis of concentration levels allowed the establishment of different groups of metals according to the observed behaviour, the analysis of the role of pH and the identification of the main release mechanisms. Finally, through a statistical analysis, physical parameters and diffusion data were interrelated. It allowed estimating the relevance of porosity, density and absorption of hardened concrete on diffusion release of the metals in study. Copyright © 2014 Elsevier Ltd. All rights reserved.

Production of xylanases by mangrove fungi from the Philippines and their application in enzymatic pretreatment of recycled paper pulps.

PubMed

Torres, Jeremy Martin O; Dela Cruz, Thomas Edison E

2013-04-01

Mangrove fungi are vastly unexplored for enzymes with industrial application. This study aimed to assess the biocatalytic activity of mangrove fungal xylanases on recycled paper pulp. Forty-four mangrove fungal (MF) isolates were initially screened for xylanolytic activity in minimal medium with corn cob xylan as the sole carbon source. Eight MF were further cultivated under submerged fermentation for the production of crude xylanases. These crude enzymes were then characterized and tested for the pretreatment of recycled paper pulps. Results showed that 93 % of the tested MF isolates exhibited xylanolytic activity in solid medium. In submerged fermentation, salinity improved the growth of the fungal isolates but did not influence xylanase production. The crude xylanases were mostly optimally active at 50 °C and pH 7. Changes in pH had a greater effect on xylanase stability than temperature. More than half of the activity was lost at pH 9 for majority of the crude enzymes. However, two thermophilic xylanases from Fusarium sp. KAWIT-A and Aureobasidium sp. 2LIPA-M and one alkaliphilic xylanase from Phomopsis sp. MACA-J were also produced. All crude enzymes exhibited cellulase activities ranging from 4 to 21 U/ml. Enzymatic pretreatment of recycled paper pulps with 5 % consistency produced 70-650 mg of reducing sugars per gram of pulp at 50 °C after 60 min. The release of high amounts of reducing sugars showed the potential of mangrove fungal crude xylanases in the local paper and pulp industry. The diverse properties shown by the tested crude enzymes also indicate its potential applications to other enzyme-requiring industries.

Experimental Study on the Seismic Performance of Recycled Concrete Brick Walls Embedded with Vertical Reinforcement.

PubMed

Cao, Wanlin; Zhang, Yongbo; Dong, Hongying; Zhou, Zhongyi; Qiao, Qiyun

2014-08-19

Recycled concrete brick (RCB) is manufactured by recycled aggregate processed from discarded concrete blocks arising from the demolishing of existing buildings. This paper presents research on the seismic performance of RCB masonry walls to assess the applicability of RCB for use in rural low-rise constructions. The seismic performance of a masonry wall is closely related to the vertical load applied to the wall. Thus, the compressive performance of RCB masonry was investigated firstly by constructing and testing eighteen RCB masonry compressive specimens with different mortar strengths. The load-bearing capacity, deformation and failure characteristic were analyzed, as well. Then, a quasi-static test was carried out to study the seismic behavior of RCB walls by eight RCB masonry walls subjected to an axial compressive load and a reversed cyclic lateral load. Based on the test results, equations for predicting the compressive strength of RCB masonry and the lateral ultimate strength of an RCB masonry wall were proposed. Experimental values were found to be in good agreement with the predicted values. Meanwhile, finite element analysis (FEA) and parametric analysis of the RCB walls were carried out using ABAQUS software. The elastic-plastic deformation characteristics and the lateral load-displacement relations were studied.

Experimental Study on the Seismic Performance of Recycled Concrete Brick Walls Embedded with Vertical Reinforcement

PubMed Central

Cao, Wanlin; Zhang, Yongbo; Dong, Hongying; Zhou, Zhongyi; Qiao, Qiyun

2014-01-01

Recycled concrete brick (RCB) is manufactured by recycled aggregate processed from discarded concrete blocks arising from the demolishing of existing buildings. This paper presents research on the seismic performance of RCB masonry walls to assess the applicability of RCB for use in rural low-rise constructions. The seismic performance of a masonry wall is closely related to the vertical load applied to the wall. Thus, the compressive performance of RCB masonry was investigated firstly by constructing and testing eighteen RCB masonry compressive specimens with different mortar strengths. The load-bearing capacity, deformation and failure characteristic were analyzed, as well. Then, a quasi-static test was carried out to study the seismic behavior of RCB walls by eight RCB masonry walls subjected to an axial compressive load and a reversed cyclic lateral load. Based on the test results, equations for predicting the compressive strength of RCB masonry and the lateral ultimate strength of an RCB masonry wall were proposed. Experimental values were found to be in good agreement with the predicted values. Meanwhile, finite element analysis (FEA) and parametric analysis of the RCB walls were carried out using ABAQUS software. The elastic-plastic deformation characteristics and the lateral load-displacement relations were studied. PMID:28788170

Ceramic ware waste as coarse aggregate for structural concrete production.

PubMed

García-González, Julia; Rodríguez-Robles, Desirée; Juan-Valdés, Andrés; Morán-Del Pozo, Julia M; Guerra-Romero, M Ignacio

2015-01-01

The manufacture of any kind of product inevitably entails the production of waste. The quantity of waste generated by the ceramic industry, a very important sector in Spain, is between 5% and 8% of the final output and it is therefore necessary to find an effective waste recovery method. The aim of the study reported in the present article was to seek a sustainable means of managing waste from the ceramic industry through the incorporation of this type of waste in the total replacement of conventional aggregate (gravel) used in structural concrete. Having verified that the recycled ceramic aggregates met all the technical requirements imposed by current Spanish legislation, established in the Code on Structural Concrete (EHE-08), then it is prepared a control concrete mix and the recycled concrete mix using 100% recycled ceramic aggregate instead of coarse natural aggregate. The concretes obtained were subjected to the appropriate tests in order to conduct a comparison of their mechanical properties. The results show that the concretes made using ceramic sanitary ware aggregate possessed the same mechanical properties as those made with conventional aggregate. It is therefore possible to conclude that the reuse of recycled ceramic aggregate to produce recycled concrete is a feasible alternative for the sustainable management of this waste.

Microalgae recycling improves biomass recovery from wastewater treatment high rate algal ponds.

PubMed

Gutiérrez, Raquel; Ferrer, Ivet; González-Molina, Andrés; Salvadó, Humbert; García, Joan; Uggetti, Enrica

2016-12-01

Microalgal biomass harvesting by inducing spontaneous flocculation (bioflocculation) sets an attractive approach, since neither chemicals nor energy are needed. Indeed, bioflocculation may be promoted by recycling part of the harvested microalgal biomass to the photobioreactor in order to increase the predominance of rapidly settling microalgae species. The aim of the present study was to improve the recovery of microalgal biomass produced in wastewater treatment high rate algal ponds (HRAPs) by recycling part of the harvested microalgal biomass. The recirculation of 2% and 10% (dry weight) of the HRAPs microalgal biomass was tested over one year in an experimental HRAP treating real urban wastewater. Results indicated that biomass recycling had a positive effect on the harvesting efficiency, obtaining higher biomass recovery in the HRAP with recycling (R-HRAP) (92-94%) than in the control HRAP without recycling (C-HRAP) (75-89%). Microalgal biomass production was similar in both systems, ranging between 3.3 and 25.8 g TSS/m 2 d, depending on the weather conditions. Concerning the microalgae species, Chlorella sp. was dominant overall the experimental period in both HRAPs (abundance >60%). However, when the recycling rate was increased to 10%, Chlorella sp. dominance decreased from 97.6 to 88.1%; while increasing the abundance of rapidly settling species such as Stigeoclonium sp. (16.8%, only present in the HRAP with biomass recycling) and diatoms (from 0.7 to 7.3%). Concerning the secondary treatment of the HRAPs, high removals of COD (80%) and N-NH 4 + (97%) were found in both HRAPs. Moreover, by increasing the biomass recovery in the R-HRAP the effluent total suspended solids (TSS) concentration was decreased to less than 35 mg/L, meeting effluent quality requirements for discharge. This study shows that microalgal biomass recycling (10% dry weight) increases biomass recovery up to 94% by selecting the most rapidly settling microalgae species without compromising the biomass production and improving the wastewater treatment in terms of TSS removal. Copyright © 2016 Elsevier Ltd. All rights reserved.

Structural study of cold central plant recycling sections at the National Center for Asphalt Technology (NCAT) test track.

DOT National Transportation Integrated Search

2016-01-01

In 2012, the Virginia Department of Transportation (VDOT) contracted with the National Center for Asphalt Technology (NCAT) to install, instrument, and monitor three pavement test sections at the NCAT Test Track during the 2012-2014 track cycle. The ...

16 CFR 311.4 - Testing.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Testing. 311.4 Section 311.4 Commercial... STANDARDS FOR RECYCLED OIL § 311.4 Testing. To determine the substantial equivalency of processed used oil... were reported to the Commission by the National Institutes of Standards and Technology (“NIST”) on July...

Design, fabrication and testing of a dual catalyst ammonia removal system for a urine VCD unit

NASA Technical Reports Server (NTRS)

Budinikas, P.

1980-01-01

A three-man capacity catalytic system for the recovery of water from urine was designed, constructed, and tested, it was designed to operate with feed streams containing high concentrations of urine vapor and only 5 to 7% of oxygen for the oxidation of ammonia and volatile organic vapor.It can operate either in a flow-through or a recycle mode and is capable of accepting the urine vapor produced by a vapor compression distillation evaporator. Testing consisted of short preliminary and optimization test, an endurance test of 74 hours continuous operation, and recycle tests using both air and oxygen. The system was designed for a urine processing rate of 0.86 liters/hr; however, it was tested at rates up to 1.2 liter/hr. Untreated urine evaporated by an electrically heated evaporator was used. The quality of the recovered water meets the U.S. Drinking Water Standards, with the exception of a low pH. Accumulation of solids in the urine sludge is reduced to approximately 65% of the anticipated value.

GENERIC VERIFICATION PROTOCOL FOR AQUEOUS CLEANER RECYCLING TECHNOLOGIES

EPA Science Inventory

This generic verification protocol has been structured based on a format developed for ETV-MF projects. This document describes the intended approach and explain plans for testing with respect to areas such as test methodology, procedures, parameters, and instrumentation. Also ...

Recycling of woven carbon-fibre-reinforced polymer composites using supercritical water.

PubMed

Knight, Chase C; Zeng, Changchun; Zhang, Chuck; Wang, Ben

2012-01-01

Over the past few years, there has been great deal of interest in recycling carbon-fibre-reinforced polymer composites. One method that has shown promising results involves the use of supercritical fluids to achieve separation between matrix and fibres by effectively degrading the resin into lower molecular weight compounds. In addition, the solvents used are environmentally benign and can also be recovered and reused. In this study, supercritical water with 0.05 M KOH as the catalyst was used for the recycling of an aerospace-grade high-performance epoxy carbon fibre composite (Hexcel 8552/IM7). The morphology of the reclaimed fibres was observed by scanning electron microscopy, and the tensile properties of the fibres were measured by single filament testing. The effects of processing time on the resin elimination efficiency and fibre property retention were investigated. With the process developed in this research, as much as 99.2 wt% resin elimination was achieved, resulting in the recovery of clean, undamaged fibres. The reclaimed fibres retained the original tensile strength. The feasibility of recycling multiple layer composites was also explored.

Characterization of Fine Metal Particles Derived from Shredded WEEE Using a Hyperspectral Image System: Preliminary Results

PubMed Central

Candiani, Gabriele; Picone, Nicoletta; Pompilio, Loredana; Pepe, Monica; Colledani, Marcello

2017-01-01

Waste of electric and electronic equipment (WEEE) is the fastest-growing waste stream in Europe. The large amount of electric and electronic products introduced every year in the market makes WEEE disposal a relevant problem. On the other hand, the high abundance of key metals included in WEEE has increased the industrial interest in WEEE recycling. However, the high variability of materials used to produce electric and electronic equipment makes key metals’ recovery a complex task: the separation process requires flexible systems, which are not currently implemented in recycling plants. In this context, hyperspectral sensors and imaging systems represent a suitable technology to improve WEEE recycling rates and the quality of the output products. This work introduces the preliminary tests using a hyperspectral system, integrated in an automatic WEEE recycling pilot plant, for the characterization of mixtures of fine particles derived from WEEE shredding. Several combinations of classification algorithms and techniques for signal enhancement of reflectance spectra were implemented and compared. The methodology introduced in this study has shown characterization accuracies greater than 95%. PMID:28505070

Expression and localization of exocytic and recycling Rabs from Magnaporthe oryzae in mammalian cells

PubMed Central

Qi, Yaoyao; Marlin, M. Caleb; Liang, Zhimin; Zhang, Dongmei; Zhou, Jie; Wang, Zonghua; Lu, Guodong; Li, Guangpu

2018-01-01

Rab GTPases are master regulators of intracellular membrane trafficking along endocytic and exocytic pathways. In this chapter, we began to characterize the exocytic and recycling Rabs from the filamentous fungus Magnaporthe oryzae (M. oryzae) that causes the rice blast disease. Among the 11 putative Rabs identified from the M. oryzae genome database (MoRabs), MoRab1, MoRab8, and MoRab11 appear orthologs of mammalian Rab1, Rab8, and Rab11 and likely function in exocytosis and endosomal recycling. To test this contention, we cloned, expressed, and determined intracellular localization of the three MoRabs in mammalian cells, in comparison to their human counterparts (hRabs). The MoRabs were well expressed as GFP fusion proteins and colocalized with the tdTomato-labeled hRabs on exocytic and recycling organelles, as determined by immunoblot analysis and confocal fluorescence microscopy. The colocalization supports the contention that the MoRabs are indeed Rab orthologs and may play important roles in the development and pathogenicity of M. oryzae. PMID:26360026

Biomass recycle as a means to improve the energy efficiency of CELSS algal culture systems

NASA Technical Reports Server (NTRS)

Radmer, R.; Cox, J.; Lieberman, D.; Behrens, P.; Arnett, K.

1987-01-01

Algal cultures can be very rapid and efficient means to generate biomass and regenerate the atmosphere for closed environmental life support systems. However, as in the case of most higher plants, a significant fraction of the biomass produced by most algae cannot be directly converted to a useful food product by standard food technology procedures. This waste biomass will serve as an energy drain on the overall system unless it can be efficiently recycled without a significant loss of its energy content. Experiments are reported in which cultures of the alga Scenedesmus obliquus were grown in the light and at the expense of an added carbon source, which either replaced or supplemented the actinic light. As part of these experiments, hydrolyzed waste biomass from these same algae were tested to determine whether the algae themselves could be made part of the biological recycling process. Results indicate that hydrolyzed algal (and plant) biomass can serve as carbon and energy sources for the growth of these algae, suggesting that the efficiency of the closed system could be significantly improved using this recycling process.

Efficient prepreg recycling at low temperatures

NASA Astrophysics Data System (ADS)

Pannkoke, Kord; Oethe, Marcus; Busse, Jürgen

When manufacturing fibre reinforced plastics engineers are still confronted with a lack of experience concerning efficient recycling methods for prepreg cutting waste. Normally, the prepregs are cured and subsequently milled to use them as a filler material for polymers. However, this method is expensive and it is difficult to find applications for the milled FRP. An alternative method to recycle CFRP prepregs will be presented in this paper. Cutting the uncured prepreg waste was done by means of a saw mill which was cooled down to low temperatures. Working temperatures of -30°C are sufficient to harden the uncured resin and to achieve cuttable prepregs. Furthermore, post-curing during the cutting process is avoided with this technique. The result is a `cotton'-like matted structure with random fibre orientation and fibre length distribution. Subsequent curing was done by means of a press and an autoclave, respectively. It will be shown by means of tension and bending tests that low-temperature cutting of uncured prepregs is a way to partly conserve the high valuation of FRP during recycling. Furthermore, it offers possibilities for various applications.

Chromium release from new stainless steel, recycled and nickel-free orthodontic brackets.

PubMed

Sfondrini, Maria Francesca; Cacciafesta, Vittorio; Maffia, Elena; Massironi, Sarah; Scribante, Andrea; Alberti, Giancarla; Biesuz, Raffaela; Klersy, Catherine

2009-03-01

To test the hypothesis that there is no difference in the amounts of chromium released from new stainless steel brackets, recycled stainless steel brackets, and nickel-free (Ni-free) orthodontic brackets. This in vitro study was performed using a classic batch procedure by immersion of the samples in artificial saliva at various acidities (pH 4.2, 6.5, and 7.6) over an extended time interval (t(1) = 0.25 h, t(2) = 1 h, t(3) = 24 h, t(4) = 48 h, t(5) = 120 h). The amount of chromium release was determined using an atomic absorption spectrophotometer and an inductively coupled plasma atomic emission spectrometer. Statistical analysis included a linear regression model for repeated measures, with calculation of Huber-White robust standard errors to account for intrabracket correlation of data. For post hoc comparisons the Bonferroni correction was applied. The greatest amount of chromium was released from new stainless steel brackets (0.52 +/- 1.083 microg/g), whereas the recycled brackets released 0.27 +/- 0.38 microg/g. The smallest release was measured with Ni-free brackets (0.21 +/- 0.51 microg/g). The difference between recycled brackets and Ni-free brackets was not statistically significant (P = .13). For all brackets, the greatest release (P = .000) was measured at pH 4.2, and a significant increase was reported between all time intervals (P < .002). The hypothesis is rejected, but the amount of chromium released in all test solutions was well below the daily dietary intake level.

Optimisation of industrial wastes reuse as construction materials.

PubMed

Collivignarelli, C; Sorlini, S

2001-12-01

This study concerns the reuse of two inorganic wastes, foundry residues and fly ashes from municipal solid waste incineration, as "recycled aggregate" in concrete production. This kind of reuse was optimised by waste treatment with the following steps: waste washing with water; waste stabilisation-solidification treatment with inorganic reagents; final grinding of the stabilised waste after curing for about 10-20 days. Both the treated wastes were reused in concrete production with different mix-designs. Concrete specimens were characterised by means of conventional physical-mechanical tests (compression, elasticity modulus, shrinkage) and different leaching tests. Experimental results showed that a good structural and environmental quality of "recycled concrete" is due both to a correct waste treatment and to a correct mix-design for concrete mixture.

Recycle of Zirconium from Used Nuclear Fuel Cladding: A Major Element of Waste Reduction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Collins, Emory D; DelCul, Guillermo D; Terekhov, Dmitri

2011-01-01

Feasibility tests were initiated to determine if the zirconium in commercial used nuclear fuel (UNF) cladding can be recovered in sufficient purity to permit re-use, and if the recovery process can be operated economically. Initial tests are being performed with unirradiated, non-radioactive samples of various types of Zircaloy materials that are used in UNF cladding to develop the recovery process and determine the degree of purification that can be obtained. Early results indicate that quantitative recovery can be accomplished and product contamination with alloy constituents can be controlled sufficiently to meet purification requirements. Future tests with actual radioactive UNF claddingmore » are planned. The objective of current research is to determine the feasibility of recovery and recycle of zirconium from used fuel cladding wastes. Zircaloy cladding, which contains 98+% of hafnium-free zirconium, is the second largest mass, on average {approx}25 wt %, of the components in used U.S. light-water-reactor fuel assemblies. Therefore, recovery and recycle of the zirconium would enable a large reduction in geologic waste disposal for advanced fuel cycles. Current practice is to compact or grout the cladding waste and store it for subsequent disposal in a geologic repository. This paper describes results of initial tests being performed with unirradiated, non-radioactive samples of various types of Zircaloy materials that are used in UNF cladding to develop the recovery process and determine the degree of purification that can be obtained. Future tests with actual radioactive UNF cladding are planned.« less

Research on Durability of Recycled Ceramic Powder Concrete

NASA Astrophysics Data System (ADS)

Chen, M. C.; Fang, W.; Xu, K. C.; Xie, L.

2017-06-01

Ceramic was ground into powder with 325 mesh and used to prepare for concrete. Basic mechanical properties, carbonation and chloride ion penetration of the concrete tests were conducted. In addition, 6-hour electric fluxes of recycled ceramic powder concrete were measured under loading. The results showed that the age strength of ceramics powder concrete is higher than that of the ordinary concrete and the fly ash concrete. The ceramic powder used as admixture would reduce the strength of concrete under no consideration of its impact factor; under consideration of the impact factor for ceramic powder as admixture, the carbonation resistance of ceramic powder concrete was significantly improved, and the 28 day carbonation depth of the ceramic powder concrete was only 31.5% of ordinary concrete. The anti-chloride-permeability of recycled ceramic powder concrete was excellent.

Separation and collection of coarse aggregate from waste concrete by electric pulsed power

NASA Astrophysics Data System (ADS)

Shigeishi, Mitsuhiro

2017-09-01

Waste concrete accounts for a substantial fraction of construction waste, and the recycling of waste concrete as concrete aggregate for construction is an important challenge associated with the rapid increase in the amount of waste concrete and the tight supply of natural aggregate. In this study, we propose a technique based on the use of high-voltage pulsed electric discharge into concrete underwater for separating and collecting aggregate from waste concrete with minimal deterioration of quality. By using this technique, the quality of the coarse aggregate separated and collected from concrete test specimens is comparable to that of coarse aggregate recycled by heating and grinding methods, thus satisfying the criteria in Japan Industrial Standard (JIS) A 5021 for the oven-dry density and the water absorption of coarse aggregate by advanced recycling.

Understanding the impact of flow rate and recycle on the conversion of a complex biorefinery stream using a flow-through microbial electrolysis cell

DOE PAGES

Lewis, Alex J.; Borole, Abhijeet P.

2016-06-16

We investigated the effect of flow rate and recycle on the conversion of a biomass-derived pyrolysis aqueous phase in amicrobial electrolysis cell (MEC) to demonstrate production of renewable hydrogen in biorefinery. A continuous MEC operation was investigated under one-pass and recycle conditions usingthe complex, biomass-derived, fermentable, mixed substrate feed at a constant concentration of 0.026 g/L,while testing flow rates ranging from 0.19 to 3.6 mL/min. This corresponds to an organic loading rate (OLR) of 0.54₋10 g/L-day. Mass transfer issues observed at low flow rates were alleviated using high flow rates.Increasing the flow rate to 3.6 mL/min (3.7 min HRT) duringmore » one-pass operation increased the hydrogen productivity 3-fold, but anode conversion efficiency (ACE) decreased from 57.9% to 9.9%. Recycle of the anode liquid helped to alleviate kinetic limitations and the ACE increased by 1.8-fold and the hydrogen productivity by 1.2-fold compared to the one-pass condition at the flow rate of 3.6 mL/min (10 g/L-d OLR). High COD removal was also achieved under recycle conditions, reaching 74.2 1.1%, with hydrogen production rate of 2.92 ± 0.51 L/L-day. This study demonstrates the advantages of combining faster flow rates with a recycle process to improve rate of hydrogen production from a switchgrass-derived stream in the biorefinery.« less

Neuron recycling for learning the alphabetic principles.

PubMed

Scliar-Cabral, Leonor

2014-01-01

The main purpose of this paper is to discuss an approach to the phonic method of learning-teaching early literacy development, namely that the visual neurons must be recycled to recognize the small differences among pertinent letter features. In addition to the challenge of segmenting the speech chain and the syllable for learning the alphabetic principles, neuroscience has demonstrated another major challenge: neurons in mammals are programmed to process visual signals symmetrically. In order to develop early literacy, visual neurons must be recycled to overcome this initial programming together with phonological awareness, expanding it with the ability to delimit words, including clitics, as well as assigning stress to words. To achieve this goal, Scliar's Early Literacy Development System was proposed and tested. Sixteen subjects (10 girls and 6 boys) comprised the experimental group (mean age 6.02 years), and 16 subjects (7 girls and 9 boys) formed the control group (mean age 6.10 years). The research instruments were a psychosociolinguistic questionnaire to reveal the subjects' profile and a post-test battery of tests. At the beginning of the experiment, the experimental group was submitted to an intervention program based on Scliar's Early Literacy Development System. One of the tests is discussed in this paper, the grapheme-phoneme test: subjects had to read aloud a pseudoword with 4 graphemes, signaled by the experimenter and designed to assess the subject's ability to convert a grapheme into its correspondent phoneme. The average value for the test group was 25.0 correct answers (SD = 11.4); the control group had an average of 14.3 correct answers (SD = 10.6): The difference was significant. The experimental results validate Scliar's Early Literacy Development System and indicate the need to redesign early literacy development methods. © 2014 S. Karger AG, Basel.

Recycling potential of post-consumer plastic packaging waste in Finland.

PubMed

Dahlbo, Helena; Poliakova, Valeria; Mylläri, Ville; Sahimaa, Olli; Anderson, Reetta

2018-01-01

Recycling of plastics is urged by the need for closing material loops to maintain our natural resources when striving towards circular economy, but also by the concern raced by observations of plastic scrap in oceans and lakes. Packaging industry is the sector using the largest share of plastics, hence packaging dominates in the plastic waste flow. The aim of this paper was to sum up the recycling potential of post-consumer plastic packaging waste in Finland. This potential was evaluated based on the quantity, composition and mechanical quality of the plastic packaging waste generated by consumers and collected as a source-separated fraction, within the mixed municipal solid waste (MSW) or within energy waste. Based on the assessment 86,000-117,000 tons (18 kg/person/a) of post-consumer plastic packaging waste was generated in Finland in 2014. The majority, 84% of the waste was in the mixed MSW flow in 2014. Due to the launching of new sorting facilities and separate collections for post-consumer plastic packaging in 2016, almost 40% of the post-consumer plastic packaging could become available for recycling. However, a 50% recycling rate for post-consumer plastic packaging (other than PET bottles) would be needed to increase the overall MSW recycling rate from the current 41% by around two percentage points. The share of monotype plastics in the overall MSW plastics fraction was 80%, hence by volume the recycling potential of MSW plastics is high. Polypropylene (PP) and low density polyethylene (LDPE) were the most common plastic types present in mixed MSW, followed by polyethylene terephthalate (PET), polystyrene (PS) and high density polyethylene (HDPE). If all the Finnish plastic packaging waste collected through the three collection types would be available for recycling, then 19,000-25,000 tons of recycled PP and 6000-8000 tons of recycled HDPE would be available on the local market. However, this assessment includes uncertainties due to performing the composition study only on mixed MSW plastic fraction. In order to obtain more precise figures of the recycling potential of post-consumer plastic packaging, more studies should be performed on both the quantities and the qualities of plastic wastes. The mechanical and rheological test results indicated that even plastic wastes originating from the mixed MSW, can be useful raw materials. Recycled HDPE showed a smaller decline in the mechanical properties than recycled PP. The origin and processing method of waste plastic seemed to have less effect on the mechanical quality than the type of plastic. The applicability of a plastic waste for a product needs to be assessed case by case, due to product specific quality requirements. In addition to mechanical properties, the chemical composition of plastic wastes is of major importance, in order to be able to restrict hazardous substances from being circulated undesirably. In addition to quantity and quality of plastic wastes, the sustainability of the whole recycling chain needs to be assessed prior to launching operations so that the chain can be optimized to generate both environmental and economic benefits to society and operators. Copyright © 2017 Elsevier Ltd. All rights reserved.

Caustic Recycling Pilot Unit to Separate Sodium from LLW at Hanford Site - 12279

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pendleton, Justin; Bhavaraju, Sai; Priday, George

As part of the Department of Energy (DOE) sponsored Advanced Remediation Technologies initiative, a scheme was developed to combine Continuous Sludge Leaching (CSL), Near-Tank Cesium Removal (NTCR), and Caustic Recycling Unit (CRU) using Ceramatec technology, into a single system known as the Pilot Near-Tank Treatment System (PNTTS). The Cesium (Cs) decontaminated effluent from the NTCR process will be sent to the caustic recycle process for recovery of the caustic which will be reused in another cycle of caustic leaching in the CSL process. Such an integrated mobile technology demonstration will give DOE the option to insert this process for sodiummore » management at various sites in Hanford, and will minimize the addition of further sodium into the waste tanks. This allows for recycling of the caustic used to remove aluminum during sludge washing as a pretreatment step in the vitrification of radioactive waste which will decrease the Low Level Waste (LLW) volume by as much as 39%. The CRU pilot process was designed to recycle sodium in the form of pure sodium hydroxide. The basis for the design of the 1/4 scale pilot caustic recycling unit was to demonstrate the efficient operation of a larger scale system to recycle caustic from the NTCR effluent stream from the Parsons process. The CRU was designed to process 0.28 liter/minute of NTCR effluent, and generate 10 M concentration of 'usable' sodium hydroxide. The proposed process operates at 40 deg. C to provide additional aluminum solubility and then recover the sodium hydroxide to the point where the aluminum is saturated at 40 deg. C. A system was developed to safely separate and vent the gases generated during operation of the CRU with the production of 10 M sodium hydroxide. Caustic was produced at a rate between 1.9 to 9.3 kg/hr. The CRU was located inside an ISO container to allow for moving of the unit close to tank locations to process the LLW stream. Actual tests were conducted with the NTCR effluent simulant from the Parsons process in the CRU. The modular CRU is easily scalable as a standalone system for caustic recycling, or for NTTS integration or for use as an In-Tank Treatment System to process sodium bearing waste to meet LLW processing needs at the Hanford site. The standalone pilot operation of the CRU to recycle sodium from NTCR effluent places the technology demonstration at TRL level 6. Multiple operations were performed with the CRU to process up to 500 gallons of the NTCR effluent and demonstrate an efficient separation of up to 70 % of the sodium without solids precipitation while producing 10 M caustic. Batch mode operation was conducted to study the effects of chemistry variation, establish the processing rate, and optimize the process operating conditions to recycle caustic from the NTCR effluent. The performance of the CRU was monitored by tracking the density parameter to control the concentration of caustic produced. Different levels of sodium were separated in tests from the effluent at a fixed operating current density and temperature. The voltage of the modules remained stable during the unit operation which demonstrated steady operation to separate sodium from the NTCR effluent. The sodium transfer current efficiency was measured in testing based on the concentration of caustic produced. Measurements showed a current efficiency of 99.8% for sodium transfer from the NTCR effluent to make sodium hydroxide. The sodium and hydroxide contents of the anolyte (NTCR feed) and catholyte (caustic product) were measured before and after each batch test. In two separate batch tests, samples were taken at different levels of sodium separation and analyzed to determine the stability of the NTCR effluent after sodium separation. The stability characteristics and changes in physical and chemical properties of the NTCR effluent chemistry after separation of sodium hydroxide as a function of storage time were evaluated. Parameters such as level of precipitated alumina, total alkalinity, analysis of Al, Na, K, Cs, Fe, OH, nitrate, nitrite, total dissolved and undissolved solids, viscosity, density, and other parameters of the NTCR effluent were measured. Changes in rheology and properties of NTCR stream to support downstream handling of the effluent after sodium separation was the basis for the analysis. The results show that the NTCR effluent is stable without the precipitation of aluminum hydroxide after 70% of the sodium was separated from the effluent. (authors)« less

TECHNETIUM RETENTION IN WTP LAW GLASS WITH RECYCLE FLOW-SHEET DM10 MELTER TESTING VSL-12R2640-1 REV 0

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abramowitz, Howard; Brandys, Marek; Cecil, Richard

2012-12-11

Melter tests were conducted to determine the retention of technetium and other volatiles in glass while processing simulated Low Activity Waste (LAW) streams through a DM10 melter equipped with a prototypical off-gas system that concentrates and recycles fluid effiuents back to the melter feed. To support these tests, an existing DM10 system installed at Vitreous State Laboratory (VSL) was modified to add the required recycle loop. Based on the Hanford Tank Waste Treatment and Immobilization Plant (WTP) LAW off-gas system design, suitably scaled versions of the Submerged Bed Scrubber (SBS), Wet Electrostatic Precipitator (WESP), and TLP vacuum evaporator were designed,more » built, and installed into the DM10 system. Process modeling was used to support this design effort and to ensure that issues associated with the short half life of the {sup 99m}Tc radioisotope that was used in this work were properly addressed and that the system would be capable of meeting the test objectives. In particular, this required that the overall time constant for the system was sufficiently short that a reasonable approach to steady state could be achieved before the {sup 99m}Tc activity dropped below the analytical limits of detection. The conceptual design, detailed design, flow sheet development, process model development, Piping and Instrumentation Diagram (P&ID) development, control system design, software design and development, system fabrication, installation, procedure development, operator training, and Test Plan development for the new system were all conducted during this project. The new system was commissioned and subjected to a series of shake-down tests before embarking on the planned test program. Various system performance issues that arose during testing were addressed through a series of modifications in order to improve the performance and reliability of the system. The resulting system provided a robust and reliable platform to address the test objectives.« less

Recycling of car tires by means of Waterjet technologies

NASA Astrophysics Data System (ADS)

Holka, Henryk; Jarzyna, Tomasz

2017-03-01

An increasing number of used car tires poses a threat to the environment. Therefore they need to be recycled. In this work a decomposition method that involves applying a stream of water at very high pressure (to 600MPa) is presented. This method is based on the authors' own patent from 2010 and the results have been provided from two year-long tests and calculations This study includes many diagrams, images and calculations that have been used to develop the discussed method which is competitive for currently used ones.

Active monitoring as cognitive control of grinders design

NASA Astrophysics Data System (ADS)

Flizikowski, Jozef B.; Mrozinski, Adam; Tomporowski, Andrzej

2017-03-01

A general monitoring methodology applicable to plastics recyclates grinding processes development for energy engineering, has been presented in this work. The method includes two beings: mathematical aiding an invention and working of a novelty. The common set is composed of characteristics, structure, relationships of knowledge about states and transformations, effectiveness and progress of the devices and machinery engineering, e.g. breaking up in the energy-materials recycling process. This innovations theory is identified by the valuation, estimation, testing and creative archiving the elaborated character and structure of the invention and grinders construction development.

Preliminary experimental results of gas recycling subsystems except carbon dioxide concentration

NASA Technical Reports Server (NTRS)

Otsuji, K.; Sawada, T.; Satoh, S.; Kanda, S.; Matsumura, H.; Kondo, S.; Otsubo, K.

1987-01-01

Oxygen concentration and separation is an essential factor for air recycling in a controlled ecological life support system (CELSS). Furthermore, if the value of the plant assimilatory quotient is not coincident with that of the animal respiratory quotient, the recovery of oxygen from the concentrated CO2 through chemical methods will become necessary to balance the gas contents in a CELSS. Therefore, oxygen concentration and separation equipment using Salcomine and O2 recovery equipment, such as Sabatier and Bosch reactors, were experimentally developed and tested.

High-Tech, Low-Temp Insulation

NASA Technical Reports Server (NTRS)

1998-01-01

Under an SBIR (Small Business Innovative Research) contract with Ames, S.D. Miller & Associates developed new manufacturing methods for multi-layer metal spacecraft insulation that could significantly reduce launch weight and launch costs. The new honeycomb structure is more efficient than fibers for insulation. Honeycombs can be made from metals for high temperature uses, even plastic insulation from recycled milk bottles. Under development are blankets made from recycled milk bottles which will be field tested by the Red Cross and ambulance companies. Currently available are honeycomb mittens based on the same technology.

Discharge runaway in high power impulse magnetron sputtering of carbon: the effect of gas pressure, composition and target peak voltage

NASA Astrophysics Data System (ADS)

Vitelaru, Catalin; Aijaz, Asim; Constantina Parau, Anca; Kiss, Adrian Emil; Sobetkii, Arcadie; Kubart, Tomas

2018-04-01

Pressure and target voltage driven discharge runaway from low to high discharge current density regimes in high power impulse magnetron sputtering of carbon is investigated. The main purpose is to provide a meaningful insight of the discharge dynamics, with the ultimate goal to establish a correlation between discharge properties and process parameters to control the film growth. This is achieved by examining a wide range of pressures (2–20 mTorr) and target voltages (700–850 V) and measuring ion saturation current density at the substrate position. We show that the minimum plasma impedance is an important parameter identifying the discharge transition as well as establishing a stable operating condition. Using the formalism of generalized recycling model, we introduce a new parameter, ‘recycling ratio’, to quantify the process gas recycling for specific process conditions. The model takes into account the ion flux to the target, the amount of gas available, and the amount of gas required for sustaining the discharge. We show that this parameter describes the relation between the gas recycling and the discharge current density. As a test case, we discuss the pressure and voltage driven transitions by changing the gas composition when adding Ne into the discharge. We propose that standard Ar HiPIMS discharges operated with significant gas recycling do not require Ne to increase the carbon ionization.

Progress in donor assisted coal liquefaction: Hydroaromatic compound formation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kottenstette, R.J.; Stephens, H.P.

1993-12-31

The role of hydrogen donor compounds in coal liquefaction has been extensively investigated since the mid 1960`s using model compounds and process derived hydrogen donor solvents. Our recent research and that of other investigators have shown that two model compounds in particular have great efficacy in solvating low rank coals. 1,2,3,10b tetrahydrofluoranthene (H{sub 4}Fl) and 1,2,3,6,7,8 hexahydropyrene (H{sub 6}Py) have been used to dissolve Wyodak coal to > 95% soluble material as measured by tetrahydrofuran (THF). Although these hydrogen donors are very effective, they may not be found in any significant concentrations in actual liquefaction process recycle solvents. Therefore, studiesmore » with process derived recycle materials are necessary to understand donor solvent chemistry. The objective of this paper is to present results of solvent hydrogenation experiments using heavy distillate solvents produced during testing at the Wilsonville Advanced Coal Liquefaction Test Facility. We evaluated the impact of hydrogenation conditions upon hydrogen donor formation in process derived distillates and compared these process derived solvents with the highly effective H{sub 4}Fl and H{sub 6}Py donors in coal liquefaction tests. This paper presents data on reaction conditions used for distillate hydrotreating and subsequent coal liquefaction, with an aim toward understanding the relationship between reaction conditions and donor solvent quality in recycle distillates.« less

Evaluation of Pollutant Leaching Potential of Coal Ashes for Recycling

NASA Astrophysics Data System (ADS)

Park, D.; Woo, N. C.; Kim, H.; Yoon, H.; Chung, D.

2011-12-01

By 2009, coal ashes produced from coal-based power plants in Korea have been reused as cement supplement materials; however, the rest is mostly disposed in landfills inside the plant properties. Continuous production of coal ashes and limited landfill sites require more recycles of coal ashes as base materials, specifically in constructions of roads and of huge industrial complex. Previous researches showed that coal ashes could contain various metals such as arsenic(As), chromium(Cr), lead(Pb), nickel(Ni), selenium(Se), etc. In this study, we collected four types of bottom ashes and two of fly ashes from four coal-based power plants. These ash samples were tested with distilled water through the column leaching process in oxidized conditions. The column test results were compared with those of total digestion, sequential extraction processes and TCLP. Concentrations of metals in outflows from columns are generally greater in fly ashes than in bottom ashes, specifically for As, Se, B, Sr and SO4. Only one fly ash (J2-F) shows high concentrations of arsenic and selenium in leachate. Sequential extraction results indicate that these metals are in readily soluble forms, such as adsorbed, carbonated, and reducible forms. Results of TCLP analysis indicate no potential contaminants leached from the ashes. In conclusion, recycling of coal combustion ashes could be encouraged with proper tests such as sequential and leaching experiments.

Biomarkers of mercury exposure at a mercury recycling facility in Ukraine

USGS Publications Warehouse

Gibb, H.J.; Kozlov, K.; Buckley, J.P.; Centeno, J.; Jurgenson, V.; Kolker, A.; Conko, K.; Landa, E.; Panov, B.; Panov, Y.; Xu, H.

2008-01-01

This study evaluates biomarkers of occupational mercury exposure among workers at a mercury recycling operation in Gorlovka, Ukraine. The 29 study participants were divided into three occupational categories for analysis: (1) those who worked in the mercury recycling operation (Group A, n = 8), (2) those who worked at the facility but not in the yard where the recycling was done (Group B, n = 14), and (3) those who did not work at the facility (Group C, n = 7). Urine, blood, hair, and nail samples were collected from the participants, and a questionnaire was administered to obtain data on age, gender, occupational history, smoking, alcohol consumption, fish consumption, tattoos, dental amalgams, home heating system, education, source of drinking water, and family employment in the former mercury mine/smelter located on the site of the recycling facility. Each factor was tested in a univariate regression with total mercury in urine, blood, hair, and nails. Median biomarker concentrations were 4.04 ??g/g-Cr (urine), 2.58 ??g/L (blood), 3.95 ??g/g (hair), and 1.16 ??g/g (nails). Occupational category was significantly correlated (p < 0.001) with both blood and urinary mercury concentrations but not with hair or nail mercury. Four individuals had urinary mercury concentrations in a range previously found to be associated with subtle neurological and subjective symptoms (e.g., fatigue, loss of appetite, irritability), and one worker had a urinary mercury concentration in a range associated with a high probability of neurological effects and proteinuria. Comparison of results by occupational category found that workers directly involved with the recycling operation had the highest blood and urinary mercury levels. Those who worked at the facility but were not directly involved with the recycling operation had higher levels than those who did not work at the facility. Copyright ?? 2008 JOEH, LLC.

Forest Thrives In Sludge Application Tests

Treesearch

Dale G. Brockway

1988-01-01

A six-year, state and federal research-demonstration project to recycle treated municipal wastewater sludge on forest lands has resulted in dramatic growth increase of trees, groundcover and wildlife populations.

Safety evaluation for packaging (onsite) plutonium recycle test reactor graphite cask

DOE Office of Scientific and Technical Information (OSTI.GOV)

Romano, T.

This safety evaluation for packaging (SEP) provides the evaluation necessary to demonstrate that the Plutonium Recycle Test Reactor (PRTR) Graphite Cask meets the requirements of WHC-CM-2-14, Hazardous Material Packaging and Shipping, for transfer of Type B, fissile, non-highway route controlled quantities of radioactive material within the 300 Area of the Hanford Site. The scope of this SEP includes risk, shieldling, criticality, and.tiedown analyses to demonstrate that onsite transportation safety requirements are satisfied. This SEP also establishes operational and maintenance guidelines to ensure that transport of the PRTR Graphite Cask is performed safely in accordance with WHC-CM-2-14. This SEP is validmore » until October 1, 1999. After this date, an update or upgrade to this document is required.« less

Revisiting synaptic vesicle pool localization in the Drosophila neuromuscular junction

PubMed Central

Denker, Annette; Kröhnert, Katharina; Rizzoli, Silvio O

2009-01-01

The synaptic vesicles are organized in distinct populations or ‘pools’: the readily releasable pool (the first vesicles released upon stimulation), the recycling pool (which maintains release under moderate stimulation) and the reserve pool (which is called into action only upon strong, often unphysiological stimulation). A major question in the field is whether the pools consist of biochemically different vesicles or whether the pool tag is a spatial one (with the recycling vesicles found next to the release sites, and the reserve ones farther away). A strong and stable spatial segregation has been proposed in the last decade in the Drosophila larval neuromuscular junction – albeit based solely on light microscopy experiments. We have tested here this hypothesis using electron microscopy (EM) photoconversion. We found the recycling and reserve pools to be thoroughly intermixed at the EM level, indicating that spatial location is irrelevant for the functional properties of the vesicle. PMID:19403600

Mechanisms of Phosphorus Removal by Recycled Crushed Concrete.

PubMed

Deng, Yihuan; Wheatley, Andrew

2018-02-17

Due to urbanisation, there are large amounts of waste concrete, particularly in rapidly industrialising countries. Currently, demolished concrete is mainly recycled as aggregate for reconstruction. This study has shown that larger sizes (2-5 mm) of recycled concrete aggregate (RCA) removed more than 90% of P from effluent when at pH 5. Analysis of the data, using equilibrium models, indicated a best fit with the Langmuir which predicated an adsorption capacity of 6.88 mg/g. Kinetic analysis indicated the equilibrium adsorption time was 12 h, with pseudo second-order as the best fit. The thermal dynamic tests showed that the adsorption was spontaneous and, together with the evidence from the sequential extraction and desorption experiments, indicated the initial mechanism was physical attraction to the surface followed by chemical reactions which prevented re-release. These results suggested that RCA could be used for both wastewater treatment and P recovery.

Electrochemical disinfection of repeatedly recycled blackwater in a free-standing, additive-free toilet.

PubMed

Hawkins, Brian T; Sellgren, Katelyn L; Klem, Ethan J D; Piascik, Jeffrey R; Stoner, Brian R

2017-11-01

Decentralized, energy-efficient waste water treatment technologies enabling water reuse are needed to sustainably address sanitation needs in water- and energy-scarce environments. Here, we describe the effects of repeated recycling of disinfected blackwater (as flush liquid) on the energy required to achieve full disinfection with an electrochemical process in a prototype toilet system. The recycled liquid rapidly reached a steady state with total solids reliably ranging between 0.50 and 0.65% and conductivity between 20 and 23 mS/cm through many flush cycles over 15 weeks. The increase in accumulated solids was associated with increased energy demand and wide variation in the free chlorine contact time required to achieve complete disinfection. Further studies on the system at steady state revealed that running at higher voltage modestly improves energy efficiency, and established running parameters that reliably achieve disinfection at fixed run times. These results will guide prototype testing in the field.

Recycling and characterization of carbon fibers from carbon fiber reinforced epoxy matrix composites by a novel super-heated-steam method.

PubMed

Kim, Kwan-Woo; Lee, Hye-Min; An, Jeong-Hun; Chung, Dong-Chul; An, Kay-Hyeok; Kim, Byung-Joo

2017-12-01

In order to manufacture high quality recycled carbon fibers (R-CFs), carbon fiber-reinforced composite wastes were pyrolysed with super-heated steam at 550 °C in a fixed bed reactor for varying reaction times. The mechanical and surface properties of the R-CFs were characterized with a single fiber tensile test, interface shear strength (IFSS), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The surface analysis showed that there was no matrix char residue on the fiber surfaces. The tensile strength and IFSS values of the R-CFs were 90% and 115% compared to those of virgin carbon fibers (V-CFs), respectively. The recycling efficiency of the R-CFs from the composites were strongly dependent on the pyrolysis temperature, reaction time, and super-heated steam feeding rate. Copyright © 2017 Elsevier Ltd. All rights reserved.

Influence of Na+, K+, Mn2+, Fe2+ and Zn2+ ions on the electrodeposition of Ni-Co alloys: Implications for the recycling of Ni-MH batteries

NASA Astrophysics Data System (ADS)

Blanco, S.; Orta-Rodriguez, R.; Delvasto, P.

2017-01-01

A hydrometallurgical recycling procedure for the recovery of a mixed rare earths sulfate and an electrodeposited Ni-Co alloy has been described. The latter step was found to be complex, due to the presence of several ions in the battery electrode materials. Electrochemical evaluation of the influence of the ions on the Ni-Co alloy deposition was carried out by cyclic voltammetry test. It was found that ions such as K+, Fe2+ and Mn2+ improved the current efficiency for the Ni-Co deposition process on a copper surface. On the other hand, Na+ and Zn2+ ions exhibited a deleterious behaviour, minimizing the values of the reduction current. The results were used to suggest the inclusion of additional steps in the process flow diagram of the recycling operation, in order to eliminate deleterious ions from the electroplating solution.

Green Composites Based on Blends of Polypropylene with Liquid Wood Reinforced with Hemp Fibers: Thermomechanical Properties and the Effect of Recycling Cycles.

PubMed

Cicala, Gianluca; Tosto, Claudio; Latteri, Alberta; La Rosa, Angela Daniela; Blanco, Ignazio; Elsabbagh, Ahmed; Russo, Pietro; Ziegmann, Gerhard

2017-08-26

Green composites from polypropylene and lignin-based natural material were manufactured using a melt extrusion process. The lignin-based material used was the so called "liquid wood". The PP/"Liquid Wood" blends were extruded with "liquid wood" content varying from 20 wt % to 80 wt %. The blends were thoroughly characterized by flexural, impact, and dynamic mechanical testing. The addition of the Liquid Wood resulted in a great improvement in terms of both the flexural modulus and strength but, on the other hand, a reduction of the impact strength was observed. For one blend composition, the composites reinforced with hemp fibers were also studied. The addition of hemp allowed us to further improve the mechanical properties. The composite with 20 wt % of hemp, subjected to up to three recycling cycles, showed good mechanical property retention and thermal stability after recycling.

Palladium Nanoparticle-Loaded Cellulose Paper: A Highly Efficient, Robust, and Recyclable Self-Assembled Composite Catalytic System.

PubMed

Zheng, Guangchao; Kaefer, Katharina; Mourdikoudis, Stefanos; Polavarapu, Lakshminarayana; Vaz, Belén; Cartmell, Samantha E; Bouleghlimat, Azzedine; Buurma, Niklaas J; Yate, Luis; de Lera, Ángel R; Liz-Marzán, Luis M; Pastoriza-Santos, Isabel; Pérez-Juste, Jorge

2015-01-15

We present a novel strategy based on the immobilization of palladium nanoparticles (Pd NPs) on filter paper for development of a catalytic system with high efficiency and recyclability. Oleylamine-capped Pd nanoparticles, dispersed in an organic solvent, strongly adsorb on cellulose filter paper, which shows a great ability to wick fluids due to its microfiber structure. Strong van der Waals forces and hydrophobic interactions between the particles and the substrate lead to nanoparticle immobilization, with no desorption upon further immersion in any solvent. The prepared Pd NP-loaded paper substrates were tested for several model reactions such as the oxidative homocoupling of arylboronic acids, the Suzuki cross-coupling reaction, and nitro-to-amine reduction, and they display efficient catalytic activity and excellent recyclability and reusability. This approach of using NP-loaded paper substrates as reusable catalysts is expected to open doors for new types of catalytic support for practical applications.

Mechanisms of Phosphorus Removal by Recycled Crushed Concrete

PubMed Central

Wheatley, Andrew

2018-01-01

Due to urbanisation, there are large amounts of waste concrete, particularly in rapidly industrialising countries. Currently, demolished concrete is mainly recycled as aggregate for reconstruction. This study has shown that larger sizes (2–5 mm) of recycled concrete aggregate (RCA) removed more than 90% of P from effluent when at pH 5. Analysis of the data, using equilibrium models, indicated a best fit with the Langmuir which predicated an adsorption capacity of 6.88 mg/g. Kinetic analysis indicated the equilibrium adsorption time was 12 h, with pseudo second-order as the best fit. The thermal dynamic tests showed that the adsorption was spontaneous and, together with the evidence from the sequential extraction and desorption experiments, indicated the initial mechanism was physical attraction to the surface followed by chemical reactions which prevented re-release. These results suggested that RCA could be used for both wastewater treatment and P recovery. PMID:29462987

Pilot trial on separation conditions for diaper recycling.

PubMed

Kim, Kyung-Shin; Cho, Hee-Sun

2017-09-01

By utilizing laboratory-scale tests, the optimal separation conditions for diaper recycling were identified, and then, these conditions were validated by a pilot trial. In this research, we determined the mass balances derived during various processing steps and identified the most feasible procedures to use for separating each material in the output flow. The results showed that drum screening was not able to remove all the fiber and super absorbent particles (SAP) in the plastic-rich fraction and that cellulose enzyme treatment can be a good solution. To achieve better separation of fibers and SAP, slot screening followed by a cleaner is a potential option. A feasible diaper recycling process was recommended based on these results. This process involves screening and enzymatic treatment for the plastic fraction, and screening, cleaning, and thickening for the fiber fraction. Treatment procedures were also proposed for the SAP fraction and rejected materials. Copyright © 2017. Published by Elsevier Ltd.

Complex permittivity measurements during high temperature recycling of space shuttle antenna window and dielectric heat shield materials

NASA Technical Reports Server (NTRS)

Bassett, H. L.; Bomar, S. H., Jr.

1973-01-01

The research performed and the data obtained on candidate space shuttle antenna window and heat shield materials are presented. The measurement technique employs a free-space focused beam microwave bridge for obtaining RF transmission data, and a device which rotates a sample holder which is heated on one side by natural gas-air flames. The surface temperature of each sample is monitored by IR pyrometry; embedded and rear surface thermocouples are also used in obtaining temperature data. The surface of the sample undergoing test is subjected to approximately the same temperature/time profile that occurs at a proposed antenna position on the space shuttle as it re-enters. The samples are cycled through ten of these temperature profiles to determine the recycling effects. Very little change was noted in the materials due to the recycling.

Green Composites Based on Blends of Polypropylene with Liquid Wood Reinforced with Hemp Fibers: Thermomechanical Properties and the Effect of Recycling Cycles

PubMed Central

Latteri, Alberta; La Rosa, Angela Daniela; Elsabbagh, Ahmed; Ziegmann, Gerhard

2017-01-01

Green composites from polypropylene and lignin-based natural material were manufactured using a melt extrusion process. The lignin-based material used was the so called “liquid wood”. The PP/“Liquid Wood” blends were extruded with “liquid wood” content varying from 20 wt % to 80 wt %. The blends were thoroughly characterized by flexural, impact, and dynamic mechanical testing. The addition of the Liquid Wood resulted in a great improvement in terms of both the flexural modulus and strength but, on the other hand, a reduction of the impact strength was observed. For one blend composition, the composites reinforced with hemp fibers were also studied. The addition of hemp allowed us to further improve the mechanical properties. The composite with 20 wt % of hemp, subjected to up to three recycling cycles, showed good mechanical property retention and thermal stability after recycling. PMID:28846607

The relationship between magnetic parameters and heavy metal contents of indoor dust in e-waste recycling impacted area, Southeast China.

PubMed

Zhu, Zongmin; Han, Zhixuan; Bi, Xiangyang; Yang, Wenlin

2012-09-01

Environmental contamination due to uncontrolled e-waste recycling is an emerging global problem. The aim of this study is to test the applicability of magnetic methods for detecting the metal pollutants emitted from e-waste recycling activities. Dust samples collected from a typical e-waste recycling region in Guiyu, Guangdong Province, China, were investigated using magnetic, geochemical, micro-morphological and mineralogical analysis. The values of mass-specific susceptibility (χ) and saturation isothermal remanent magnetization (SIRM) in dusts from e-waste recycling impacted areas ranged from 101 to 636×10(-8) m(3) kg(-1) and from 10.5 to 85.2×10(-3) Am(2) kg(-1), respectively. There was a significant correlation between SIRM and χ (r(2)=0.747, p<0.001), indicating that ferrimagnetic minerals were dominating χ in the dust samples. The values of χ(fd)% varied from 2.6 to 4.6% with a mean of 3.4%, which suggested that magnetic carriers in the dusts are predominately coarse-grained particles. Two shapes of magnetic particles, spherule (10-150 μm) and angular-shaped particles (30-300 μm), were identified by scanning electron microscope (SEM) and energy dispersive X-ray spectrometer (EDX) analyses. κ-T curves, magnetic hysteresis loops and X-ray diffraction (XRD) analysis indicated that these magnetic particles were magnetite and goethite. There were significant correlations between SIRM and heavy metals (especially Cd, Co, Fe, Ni and Zn) as well as the Tomlinson pollution load index (PLI) of the dust, indicating that SIRM can be used as an efficient proxy for metal pollution in the e-waste recycling impacted area. Copyright © 2012 Elsevier B.V. All rights reserved.

Life Support Goals Including High Closure and Low Mass Should Be Reconsidered Using Systems Analysis

NASA Technical Reports Server (NTRS)

Jones, Harry W.

2017-01-01

Recycling space life support systems have been built and tested since the 1960s and have operated on the International Space Station (ISS) since the mid 2000s. The development of space life support has been guided by a general consensus focused on two important related goals, increasing system closure and reducing launch mass. High closure is achieved by recycling crew waste products such as carbon dioxide and condensed humidity. Recycling directly reduces the mass of oxygen and water for the crew that must be launched from Earth. The launch mass of life support can be further reduced by developing recycling systems with lower hardware mass and reduced power. The life support consensus has also favored using biological systems. The goal of increasing closure using biological systems suggests that food should be grown in space and that biological processors be used for air, water, and waste recycling. The goal of reducing launch mass led to use of Equivalent System Mass (ESM) in life support advocacy and technology selection. The recent consensus assumes that the recycling systems architecture developed in the 1960s and implemented on ISS will be used on all future long missions. NASA and other project organizations use the standard systems engineering process to guide hardware development. The systems process was used to develop ISS life support, but it has been less emphasized in planning future systems for the moon and Mars. Since such missions are far in the future, there has been less immediate need for systems engineering analysis to consider trade-offs, reliability, and Life Cycle Cost (LCC). Preliminary systems analysis suggests that the life support consensus concepts should be revised to reflect systems engineering requirements.

Take-home lead exposure among children with relatives employed at a battery recycling facility - Puerto Rico, 2011.

PubMed

2012-11-30

The recycling of lead has increased during the past 20 years, with more workers and their families potentially being exposed to lead from recycling facilities, including facilities that recycle lead-acid batteries. During November 2010-May 2011, four voluntary blood lead screening clinics for children of employees of a battery recycling facility in Puerto Rico were conducted. A total of 227 persons from 78 families had blood lead tests. Among 68 children aged <6 years, 11 (16%) had confirmed blood lead levels (BLLs) ≥10 µg/dL, the BLL at which CDC recommended individual intervention to reduce BLLs in 2010, and 39 (57%) children aged <6 years had venous or capillary BLLs ≥5 µg/dL, the reference value for elevated BLLs in children established by CDC in 2012. To determine whether take-home lead exposure contributed to the children's BLLs of ≥10 µg/dL, vehicle and household environmental samples were collected and analyzed. Eighty-five percent of vehicle dust samples and 49% of home dust samples exceeded the U.S. Environmental Protection Agency (EPA) level of concern of ≥40 µg/ft² (430.6 µg/m²) [corrected]. EPA began clean-up of employee homes and vehicles, focusing first on homes with children with BLLs ≥10 µg/dL. EPA also required that the company set up shower facilities, shoe washes, and clean changing areas at the battery recycling facility. Lastly, CDC assigned a case manager to provide education, environmental follow-up, and case management of all children with BLLs ≥5 µg/dL. On average, children's BLLs have decreased 9.9 µg/dL since being enrolled in case management.

The Functions of Auxilin and Rab11 in Drosophila Suggest That the Fundamental Role of Ligand Endocytosis in Notch Signaling Cells Is Not Recycling

PubMed Central

Bilder, David; Fischer, Janice A.

2011-01-01

Notch signaling requires ligand internalization by the signal sending cells. Two endocytic proteins, epsin and auxilin, are essential for ligand internalization and signaling. Epsin promotes clathrin-coated vesicle formation, and auxilin uncoats clathrin from newly internalized vesicles. Two hypotheses have been advanced to explain the requirement for ligand endocytosis. One idea is that after ligand/receptor binding, ligand endocytosis leads to receptor activation by pulling on the receptor, which either exposes a cleavage site on the extracellular domain, or dissociates two receptor subunits. Alternatively, ligand internalization prior to receptor binding, followed by trafficking through an endosomal pathway and recycling to the plasma membrane may enable ligand activation. Activation could mean ligand modification or ligand transcytosis to a membrane environment conducive to signaling. A key piece of evidence supporting the recycling model is the requirement in signaling cells for Rab11, which encodes a GTPase critical for endosomal recycling. Here, we use Drosophila Rab11 and auxilin mutants to test the ligand recycling hypothesis. First, we find that Rab11 is dispensable for several Notch signaling events in the eye disc. Second, we find that Drosophila female germline cells, the one cell type known to signal without clathrin, also do not require auxilin to signal. Third, we find that much of the requirement for auxilin in Notch signaling was bypassed by overexpression of both clathrin heavy chain and epsin. Thus, the main role of auxilin in Notch signaling is not to produce uncoated ligand-containing vesicles, but to maintain the pool of free clathrin. Taken together, these results argue strongly that at least in some cell types, the primary function of Notch ligand endocytosis is not for ligand recycling. PMID:21448287

NASA tests composters for space

NASA Technical Reports Server (NTRS)

Atkinson, C.

1997-01-01

For long term missions, composters may be an integral part of a life support system that provides edible food crops, extracts nutrients from plant biomass and removes contaminants from the recycling stream.

Reduce, Reuse, Recycle: The Longitudinal Value of Local Cut Scores Using State Test Data

ERIC Educational Resources Information Center

Nelson, Peter M.; Van Norman, Ethan R.; VanDerHeyden, Amanda

2017-01-01

We used existing reading (n = 1,498) and math (n = 2,260) data to evaluate state test scores for screening middle school students. In Phase 1, state test data were used to create a research-derived cut score that was optimal for predicting state test performance the following year. In Phase 2, those cut scores were applied with future cohorts.…

Comparison of recycling outcomes in three types of recycling collection units.

PubMed

Andrews, Ashley; Gregoire, Mary; Rasmussen, Heather; Witowich, Gretchen

2013-03-01

Commercial institutions have many factors to consider when implementing an effective recycling program. This study examined the effectiveness of three different types of recycling bins on recycling accuracy by determining the percent weight of recyclable material placed in the recycling bins, comparing the percent weight of recyclable material by type of container used, and examining whether a change in signage increased recycling accuracy. Data were collected over 6 weeks totaling 30 days from 3 different recycling bin types at a Midwest University medical center. Five bin locations for each bin type were used. Bags from these bins were collected, sorted into recyclable and non-recyclable material, and weighed. The percent recyclable material was calculated using these weights. Common contaminates found in the bins were napkins and paper towels, plastic food wrapping, plastic bags, and coffee cups. The results showed a significant difference in percent recyclable material between bin types and bin locations. Bin type 2 was found to have one bin location to be statistically different (p=0.048), which may have been due to lack of a trash bin next to the recycling bin in that location. Bin type 3 had significantly lower percent recyclable material (p<0.001), which may have been due to lack of a trash bin next to the recycling bin and increased contamination due to the combination of commingled and paper into one bag. There was no significant change in percent recyclable material in recycling bins post signage change. These results suggest a signage change may not be an effective way, when used alone, to increase recycling compliance and accuracy. This study showed two or three-compartment bins located next to a trash bin may be the best bin type for recycling accuracy. Copyright © 2012 Elsevier Ltd. All rights reserved.

Monitoring household waste recycling centres performance using mean bin weight analyses.

PubMed

Maynard, Sarah; Cherrett, Tom; Waterson, Ben

2009-02-01

This paper describes a modelling approach used to investigate the significance of key factors (vehicle type, compaction type, site design, temporal effects) in influencing the variability in observed nett amenity bin weights produced by household waste recycling centres (HWRCs). This new method can help to quickly identify sites that are producing significantly lighter bins, enabling detailed back-end analyses to be efficiently targeted and best practice in HWRC operation identified. Tested on weigh ticket data from nine HWRCs across West Sussex, UK, the model suggests that compaction technique, vehicle type, month and site design explained 76% of the variability in the observed nett amenity weights. For each factor, a weighting coefficient was calculated to generate a predicted nett weight for each bin transaction and three sites were subsequently identified as having similar characteristics but returned significantly different mean nett bin weights. Waste and site audits were then conducted at the three sites to try and determine the possible sources of the remaining variability. Significant differences were identified in the proportions of contained waste (bagged), wood, and dry recyclables entering the amenity waste stream, particularly at one site where significantly less contaminated waste and dry recyclables were observed.

Immobilization of metals in contaminated soil from E-waste recycling site by dairy-manure-derived biochar.

PubMed

Chen, Zhiliang; Zhang, Jianqiang; Liu, Minchao; Wu, Yingxin; Yuan, Zhihui

2017-08-24

E-waste is a growing concern around the world and varieties of abandoned E-waste recycling sites, especially in urban area, need to remediate immediately. The impacts of dairy-manure-derived biochars (BCs) on the amelioration of soil properties, the changes in the morphologies as well as the mobility of metals were studied to test their efficacy in immobilization of metals for a potential restoration of vegetation landscape in abandoned E-waste recycling site. The amendment with BCs produced positive effects on bioavailability and mobility reduction for Pb, Cd, Zn and Cu depending on BC ratio and incubation time. The BCs promoted the transformation of species of heavy metals to a more stable fraction, and the metals concentrations in Toxicity Characteristic Leaching Procedure extract declined significantly, especially Pb and Cu. Besides, the BCs ameliorated the substrate with increasing the soil pH, cations exchangeable capacity and available phosphorous, which suggested BC as a potential amendment material for abandoned E-waste recycling sites before restoration of vegetation landscape. Generally, the BC modified by alkaline treatment has a higher efficacy, probably due to increase of specific surface area and porosity as well as the functional groups after alkaline treatment.

Photovoltaic solar panels of crystalline silicon: Characterization and separation.

PubMed

Dias, Pablo Ribeiro; Benevit, Mariana Gonçalves; Veit, Hugo Marcelo

2016-03-01

Photovoltaic panels have a limited lifespan and estimates show large amounts of solar modules will be discarded as electronic waste in a near future. In order to retrieve important raw materials, reduce production costs and environmental impacts, recycling such devices is important. Initially, this article investigates which silicon photovoltaic module's components are recyclable through their characterization using X-ray fluorescence, X-ray diffraction, energy dispersion spectroscopy and atomic absorption spectroscopy. Next, different separation methods are tested to favour further recycling processes. The glass was identified as soda-lime glass, the metallic filaments were identified as tin-lead coated copper, the panel cells were made of silicon and had silver filaments attached to it and the modules' frames were identified as aluminium, all of which are recyclable. Moreover, three different components segregation methods have been studied. Mechanical milling followed by sieving was able to separate silver from copper while chemical separation using sulphuric acid was able to detach the semiconductor material. A thermo gravimetric analysis was performed to evaluate the use of a pyrolysis step prior to the component's removal. The analysis showed all polymeric fractions present degrade at 500 °C. © The Author(s) 2016.

Molecular Monte Carlo Simulations Using Graphics Processing Units: To Waste Recycle or Not?

PubMed

Kim, Jihan; Rodgers, Jocelyn M; Athènes, Manuel; Smit, Berend

2011-10-11

In the waste recycling Monte Carlo (WRMC) algorithm, (1) multiple trial states may be simultaneously generated and utilized during Monte Carlo moves to improve the statistical accuracy of the simulations, suggesting that such an algorithm may be well posed for implementation in parallel on graphics processing units (GPUs). In this paper, we implement two waste recycling Monte Carlo algorithms in CUDA (Compute Unified Device Architecture) using uniformly distributed random trial states and trial states based on displacement random-walk steps, and we test the methods on a methane-zeolite MFI framework system to evaluate their utility. We discuss the specific implementation details of the waste recycling GPU algorithm and compare the methods to other parallel algorithms optimized for the framework system. We analyze the relationship between the statistical accuracy of our simulations and the CUDA block size to determine the efficient allocation of the GPU hardware resources. We make comparisons between the GPU and the serial CPU Monte Carlo implementations to assess speedup over conventional microprocessors. Finally, we apply our optimized GPU algorithms to the important problem of determining free energy landscapes, in this case for molecular motion through the zeolite LTA.

Regulation of endocytic recycling by C. elegans Rab35 and its regulator RME-4, a coated-pit protein

PubMed Central

Sato, Miyuki; Sato, Ken; Liou, Willisa; Pant, Saumya; Harada, Akihiro; Grant, Barth D

2008-01-01

Using Caenorhabditis elegans genetic screens, we identified receptor-mediated endocytosis (RME)-4 and RME-5/RAB-35 as important regulators of yolk endocytosis in vivo. In rme-4 and rab-35 mutants, yolk receptors do not accumulate on the plasma membrane as would be expected in an internalization mutant, rather the receptors are lost from cortical endosomes and accumulate in dispersed small vesicles, suggesting a defect in receptor recycling. Consistent with this, genetic tests indicate the RME-4 and RAB-35 function downstream of clathrin, upstream of RAB-7, and act synergistically with recycling regulators RAB-11 and RME-1. We find that RME-4 is a conserved DENN domain protein that binds to RAB-35 in its GDP-loaded conformation. GFP–RME-4 also physically interacts with AP-2, is enriched on clathrin-coated pits, and requires clathrin but not RAB-5 for cortical association. GFP–RAB-35 localizes to the plasma membrane and early endocytic compartments but is lost from endosomes in rme-4 mutants. We propose that RME-4 functions on coated pits and/or vesicles to recruit RAB-35, which in turn functions in the endosome to promote receptor recycling. PMID:18354496

Proposal of a new model to improve the collection of small WEEE: a pilot project for the recovery and recycling of toys.

PubMed

Solé, Miquel; Watson, Jenna; Puig, Rita; Fullana-i-Palmer, Pere

2012-11-01

A new collection model was designed and tested in Catalonia (Spain) to foster the separate collection and recycling of electrical and electronic toys, with the participation of selected primary and secondary schools, as well as waste collection points and municipalities. This project approach is very original and important because small household WEEE has low rates of collection (16-21% WEEE within the EU or 5-7% WEEE in Spain) and no research on new approaches to enhance the collection of small WEEE is found in the literature. The project was successful in achieving enhanced toys collection and recycling rates, which went up from the national Spanish average of 0.5% toys before the project to 1.9 and 6% toys during the two project years, respectively. The environmental benefits of the campaign were calculated through a life-cycle approach, accounting for the avoided impact afforded by the reuse of the toys and the recycling of the valuable materials contained therein (such as metals, batteries and circuit boards) and subtracting the additional environmental burdens associated with the establishment of the collection campaign.

Experimental Study on Thermal Conductivity of Self-Compacting Concrete with Recycled Aggregate

PubMed Central

Fenollera, María; Míguez, José Luis; Goicoechea, Itziar; Lorenzo, Jaime

2015-01-01

The research focuses on the use of recycled aggregate (RA), from waste pieces generated during production in precast plants for self-compacting concrete (SCC) manufactured with a double sustainable goal: recycle manufacturing waste (consumption) and improvement of the thermal properties of the manufactured product (energy efficiency). For this purpose, a mechanical study to ensure technical feasibility of the concrete obtained has been conducted, as well as a thermal analysis of recycled SCC specimens of 50 N/mm2 resistance, with different RA doses (0%, 20%, 50% and 100%). The main parameters that characterize a SCC in both states, fresh (slump-flow) and hard (compressive strength), have been tested; also, a qualitative analysis of the thermal conductivity using infrared thermography (IRT) and quantitative analysis with heat flow meter at three temperatures 20 °C, 25 °C and 30 °C have been performed. The results suggest the existence of two different thermal behaviors: concretes with 0% and 20% of RA, and on the other hand concretes with 50% and 100% of RA. It has also demonstrated the validity of the IRT as sampling technique in estimating the thermal behavior of materials having reduced range of variation in parameters. PMID:28793449

Experimental Study on Thermal Conductivity of Self-Compacting Concrete with Recycled Aggregate.

PubMed

Fenollera, María; Míguez, José Luis; Goicoechea, Itziar; Lorenzo, Jaime

2015-07-20

The research focuses on the use of recycled aggregate (RA), from waste pieces generated during production in precast plants for self-compacting concrete (SCC) manufactured with a double sustainable goal: recycle manufacturing waste (consumption) and improvement of the thermal properties of the manufactured product (energy efficiency). For this purpose, a mechanical study to ensure technical feasibility of the concrete obtained has been conducted, as well as a thermal analysis of recycled SCC specimens of 50 N/mm² resistance, with different RA doses (0%, 20%, 50% and 100%). The main parameters that characterize a SCC in both states, fresh (slump-flow) and hard (compressive strength), have been tested; also, a qualitative analysis of the thermal conductivity using infrared thermography (IRT) and quantitative analysis with heat flow meter at three temperatures 20 °C, 25 °C and 30 °C have been performed. The results suggest the existence of two different thermal behaviors: concretes with 0% and 20% of RA, and on the other hand concretes with 50% and 100% of RA. It has also demonstrated the validity of the IRT as sampling technique in estimating the thermal behavior of materials having reduced range of variation in parameters.

Recycling energy to restore impaired ankle function during human walking.

PubMed

Collins, Steven H; Kuo, Arthur D

2010-02-17

Humans normally dissipate significant energy during walking, largely at the transitions between steps. The ankle then acts to restore energy during push-off, which may be the reason that ankle impairment nearly always leads to poorer walking economy. The replacement of lost energy is necessary for steady gait, in which mechanical energy is constant on average, external dissipation is negligible, and no net work is performed over a stride. However, dissipation and replacement by muscles might not be necessary if energy were instead captured and reused by an assistive device. We developed a microprocessor-controlled artificial foot that captures some of the energy that is normally dissipated by the leg and "recycles" it as positive ankle work. In tests on subjects walking with an artificially-impaired ankle, a conventional prosthesis reduced ankle push-off work and increased net metabolic energy expenditure by 23% compared to normal walking. Energy recycling restored ankle push-off to normal and reduced the net metabolic energy penalty to 14%. These results suggest that reduced ankle push-off contributes to the increased metabolic energy expenditure accompanying ankle impairments, and demonstrate that energy recycling can be used to reduce such cost.

Eco-Balance analysis of the disused lead-acid-batteries recycling technology

NASA Astrophysics Data System (ADS)

Kamińska, Ewa; Kamiński, Tomasz

2017-10-01

The article presents the results of the eco-balance analysis of the disused lead-acid batteries recycling process. Test-dedicated technology offers the possibility to recover other elements, for example, polypropylene of the battery case or to obtain crystalline sodium sulphate. The life cycle assessment was made using ReCiPe and IMPACT2002 + methods. The results are shown as environmental points [Pt]. The results are shown in the environmental categories, specific for each of the methods grouped in the impact categories. 1 Mg of the processed srap was a dopted as the functional unit. The results of the analyses indicate that recycling processes may provide the environmental impact of recycling technology less harmful. Repeated use of lead causes that its original sources are not explored. Similarly, the use of granule production-dedicated polypropylene extracted from battery casings that are used in the plastics industry, has environmental benefits. Due to the widespread use of lead-acid batteries, the attention should be paid to their proper utilization, especially in terms of heavy metals, especially lead. According to the calculations, the highest level of environmental benefits from the use of lead from secondary sources in the production of new products, was observed in the refining process.

Cold in-place recycling using solventless emulsion - phase IV (emulsion qualification and long-term field performance).

DOT National Transportation Integrated Search

2016-05-01

This report looks into how a successful Cold In-Place solventless emulsion behaves and how the emulsion : break test developed in Phase III of this project demonstrates that behavior. Modifications to the test have been : made to improve the consiste...

Auditing an intensive care unit recycling program.

PubMed

Kubicki, Mark A; McGain, Forbes; O'Shea, Catherine J; Bates, Samantha

2015-06-01

The provision of health care has significant direct environmental effects such as energy and water use and waste production, and indirect effects, including manufacturing and transport of drugs and equipment. Recycling of hospital waste is one strategy to reduce waste disposed of as landfill, preserve resources, reduce greenhouse gas emissions, and potentially remain fiscally responsible. We began an intensive care unit recycling program, because a significant proportion of ICU waste was known to be recyclable. To determine the weight and proportion of ICU waste recycled, the proportion of incorrect waste disposal (including infectious waste contamination), the opportunity for further recycling and the financial effects of the recycling program. We weighed all waste and recyclables from an 11-bed ICU in an Australian metropolitan hospital for 7 non-consecutive days. As part of routine care, ICU waste was separated into general, infectious and recycling streams. Recycling streams were paper and cardboard, three plastics streams (polypropylene, mixed plastics and polyvinylchloride [PVC]) and commingled waste (steel, aluminium and some plastics). ICU waste from the waste and recycling bins was sorted into those five recycling streams, general waste and infectious waste. After sorting, the waste was weighed and examined. Recycling was classified as achieved (actual), potential and total. Potential recycling was defined as being acceptable to hospital protocol and local recycling programs. Direct and indirect financial costs, excluding labour, were examined. During the 7-day period, the total ICU waste was 505 kg: general waste, 222 kg (44%); infectious waste, 138 kg (27%); potentially recyclable waste, 145 kg (28%). Of the potentially recyclable waste, 70 kg (49%) was actually recycled (14% of the total ICU waste). In the infectious waste bins, 82% was truly infectious. There was no infectious contamination of the recycling streams. The PVC waste was 37% contaminated (primarily by other plastics), but there was less than 1% contamination of other recycling streams. The estimated cost of the recycling program was about an additional $1000/year. In our 11-bed ICU, we recycled 14% of the total waste produced over 7-days, which was nearly half of the potentially recyclable waste. There was no infectious contamination of recyclables and minimal contamination with other waste streams, except for the PVC plastic. The estimated annual cost of the recycling program was $1000, reflecting the greater cost of disposal of some recyclables (paper and cardboard v most plastic types).

Applying the three R's: Reduce, reuse, and recycle in the chemical industry.

PubMed

Mostafa, Mohamed K; Peters, Robert W

2017-03-01

Pollution prevention (P2) assessment was conducted by applying the three R's, reduce, reuse, and recycle, in a chemical industry for the purpose of reducing the amount of wastewater generated, reusing paint wastewater in the manufacture of cement bricks, recycling cooling water, and improving water usage efficiency. The results of this study showed that the annual wastewater flow generated from the paint manufacturing can be reduced from 1,100 m 3 to 488.4 m 3 (44.4% reduction) when a high-pressure hose is used. Two mixtures were prepared. The first mixture (A) contains cement, coarse aggregate, fine aggregate, Addicrete BVF, and clean water. The second mixture (B) contains the same components used in the first mixture, except that paint wastewater was used instead of the clean water. The prepared samples were tested for water absorption, toxicity, reactivity, compressive strength, ignitability, and corrosion. The tests results indicated that using paint wastewater in the manufacture of the cement bricks improved the mechanical properties of the bricks. The toxicity test results showed that the metals concentration in the bricks did not exceed the U.S. EPA limits. This company achieved the goal of zero liquid discharge (ZLD), especially after recycling 2,800 m 3 of cooling water. The total annual saving could reach $42,570 with a payback period of 41 days. This research focused on improving the water usage efficiency, reducing the quantity of wastewater generated, and potentially reusing wastewater in the manufacture of cement bricks. Reusing paint wastewater in the manufacture of the bricks prevents the hazardous pollutants in the wastewater (calcium carbonate, styrene acrylic resins, colored pigments, and titanium dioxide) from entering and polluting the surface water and the environment. We think that this paper will help to find the most efficient and cost-effective way to manage paint wastewater and conserve fresh water resources. We also believe that this paper provides a rich agenda for future research in water conservation and industrial wastewater reuse subjects.

Materials Recycling: The Virtue of Necessity. Worldwatch Paper 56.

ERIC Educational Resources Information Center

Chandler, William U.

This report focuses on the necessity and advantages of recycling. Following an introduction, the report is divided into five sections, addressing respectively: the necessity of recycling; waste paper recycling; aluminum recycling; iron and steel recycling; and three steps to a "recycling society." These steps include: (1) requiring that consumers…

50 Simple Things Kids Can Do To Recycle. California Edition.

ERIC Educational Resources Information Center

Javna, John

This book provides 50 recycling ideas for children and features Recycle Rex, the state of California's "spokesdinosaur" for recycling. An introduction contains recycling background information on waste disposal options and reducing, reusing, and recycling. Recycling suggestions are divided into nine sections: (1) "Learn What You Can…

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cozzi, Alex D.; McCabe, Daniel J.

The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream (LAW Melter Off-Gas Condensate) from the off-gas system. The baseline plan for disposition of this stream during full WTP operations is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility. However, during the Direct Feed LAW (DFLAW) scenario, planned disposition of this stream is to evaporate it in a new evaporator in the Effluent Management Facility (EMF) and then return it to themore » LAW melter. It is important to understand the composition of the effluents from the melter and new evaporator so that the disposition of these streams can be accurately planned and accommodated. Furthermore, alternate disposition of this stream would eliminate recycling of problematic components, and would enable less integrated operation of the LAW melter and the Pretreatment Facilities. Alternate disposition would also eliminate this stream from recycling within WTP when it begins operations and would decrease the LAW vitrification mission duration and quantity of glass waste. This LAW Melter Off-Gas Condensate stream will contain components that are volatile at melter temperatures and are problematic for the glass waste form, such as halides and sulfate, along with entrained, volatile, and semi-volatile metals, such as Hg, As, and Se. Because this stream will recycle within WTP, these components accumulate in the Melter Condensate stream, exacerbating their impact on the number of LAW glass containers that must be produced. Diverting the stream reduces the halides and sulfate that get recycled to the melter, and is a key objective of this work. This overall program examines the potential treatment and immobilization of this stream to enable alternative disposal. The objective of earlier tasks was to formulate and prepare a simulant of the LAW Melter Off-gas Condensate expected during DFLAW operations and use it in evaporator testing to predict the composition of the effluents from the Effluent Management Facility (EMF) evaporator to aid in planning for their disposition. The objective of this task was to test immobilization options for this evaporator bottoms aqueous stream. This document describes the method used to formulate a simulant of this EMF evaporator bottoms stream, immobilize it, and determine if the immobilized waste forms meet disposal criteria.« less

Motivation recycling: pre-recycling case study in Minsk, Belarus.

PubMed

Miafodzyeva, Sviatlana; Brandt, Nils; Olsson, Monika

2010-04-01

Given the aim of motivating householders to behave in a recycling-friendly manner, there is a need to understand consumers' recycling behaviour. This paper documents and analyses acceptability and awareness of a pre-recycling society, through a survey carried out in the region of Minsk, Belarus. The results show a large number of people have no strong awareness about separate collection of household waste for recycling. By analysing the pre-recycling behaviour of Minsk citizens and substantive comparison with literature studies of a more mature recycling society such as Sweden, we indicate common sociodemographic variables for both cases and determine that these sociodemographic characteristics will directly influence recycling behaviour in countries like Belarus. It is also noted that the lack of recycling habit cannot directly predict subsequent recycling behaviour on the stage of implementation the recycling system.

Research of waste heat energy efficiency for absorption heat pump recycling thermal power plant circulating water

NASA Astrophysics Data System (ADS)

Zhang, Li; Zhang, Yu; Zhou, Liansheng; E, Zhijun; Wang, Kun; Wang, Ziyue; Li, Guohao; Qu, Bin

2018-02-01

The waste heat energy efficiency for absorption heat pump recycling thermal power plant circulating water has been analyzed. After the operation of heat pump, the influences on power generation and heat generation of unit were taken into account. In the light of the characteristics of heat pump in different operation stages, the energy efficiency of heat pump was evaluated comprehensively on both sides of benefits belonging to electricity and benefits belonging to heat, which adopted the method of contrast test. Thus, the reference of energy efficiency for same type projects was provided.

Toxicity tests of soil contaminated by recycling of scrap plastics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wong, M.H.; Chui, V.W.

The present investigation studied the toxicity of soil contaminated by untreated discharge from a factory that recycles used plastics. The nearby agricultural areas and freshwater fish ponds were polluted with high concentrations of Cu, Ni, and Mn. Water extracts from the contaminated soil retarded root growth of Brassica chinensis (Chinese white cabbage) and Cynodon dactylon (Bermuda grass) where their seeds were obtained commercially. The contaminated populations of C. dactylon, Panicum repen (panic grass), and Imperata cylindrica (wooly grass) were able to withstand higher concentrations of Cu, Ni, and Mn, especially C. dactylon, when compared with their uncontaminated counterparts.

Expedition 19 crew tests water from Recycling system

NASA Image and Video Library

2009-05-20

ISS019-E-018483 (20 May 2009) --- After NASA's Mission Control gave the Expedition 19 astronaut crew aboard the International Space Station a "go" to drink water that the station's new recycling system has purified, the three celebrated with a ?toast? that also involved Mission Control, Houston, and the Payload Operations Center at Marshall Space Flight Center in Huntsville, Ala., which led development of the Water Recovery System. Pictured are Expedition 19 Commander Gennady Padalka (center) and Flight Engineers Mike Barratt (right) and Koichi Wakata, holding drink bags with special commemorative labels in the Destiny laboratory.

Expedition 19 crew tests water from Recycling system

NASA Image and Video Library

2009-05-20

ISS019-E-018486 (20 May 2009) --- After NASA's Mission Control gave the Expedition 19 astronaut crew aboard the International Space Station a "go" to drink water that the station's new recycling system has purified, the three celebrated with a ?toast? that also involved Mission Control, Houston, and the Payload Operations Center at Marshall Space Flight Center in Huntsville, Ala., which led development of the Water Recovery System. Pictured are Expedition 19 Commander Gennady Padalka (center) and Flight Engineers Mike Barratt (right) and Koichi Wakata, holding drink bags with special commemorative labels in the Destiny laboratory.

Involvement of citizens in hazardous waste management and use of recycling centres in the city of Madrid (Spain).

PubMed

Díaz, María José; Martínez, Elvira; Piñeiro, Concepción; Palavecinos, Mireya; Benayas, Javier; Toribio, M Angeles

2012-07-01

In Spain, hazardous household waste management by citizens occurs via fixed recycling centres (FRC) and mobile recycling centres (MRC) which usually depend on local governments. This paper addresses a request by the Madrid City Council, in an attempt to improve the service it provides to the city of Madrid. The aim of the study involved analysing the information people possess in relation to hazardous waste and to the use of available equipment, and conducting a post-evaluation of the effectiveness of an environmental communication campaign conducted by the Madrid City Council and aimed at providing awareness of the existence of new FRCs and MRCs. To this end, a questionnaire was conducted with 5644 inhabitants of the city of Madrid. Qualitative data was categorized using content analysis followed by chi-squared tests, considering some socio-demographic characteristics of the sample, such as age or place of residence (district). Communication campaigns influenced citizen awareness of what constituted hazardous waste, of how to properly separate waste and of the existence of FRCs and MRCs. However, few citizens actually used FRCs or MRC (18% across four districts), a fact that might be related to a lack of knowledge of downstream waste treatment issues, or to self-limiting hindrances to householders, such as distance to recycling centres. It is recommended that future communication campaigns investigate householder needs and pre-conceptions in relation to recycling, as well as tailored education aimed at addressing the barriers, perceived or otherwise, facing citizens.

Parameters for assessing recycled aggregate and their correlation.

PubMed

Tam, Vivian W Y; Tam, C M

2009-02-01

Construction and demolition (C&D) waste has consumed a large portion of the landfill areas in Hong Kong. Among them, concrete occupies more than 70% of the total C&D waste by volume. Thus it is necessary to recycle concrete waste to preserve landfill areas. Various governmental departments of the Hong Kong Special Administrative Region (HKSAR) are encouraging the use of recycled aggregate (RA) in the Hong Kong construction industry by issuing various guidelines and specifications. Owing to uncertainty in their properties, however, practitioners are sceptical in using it as a substitute. In this study, an attempt has been made to look at relations among six main parameters that describe the behaviour of RA: (1) particle size distribution; (2) particle density; (3) porosity and absorption; (4) particle shape; (5) strength and toughness; and (6) chloride and sulphate contents. RA samples were obtained from nine demolition sites with service lives ranging from 10 to 40 years and another set of samples was collected from the Tuen Mun Area 38 recycling plant. The behaviour of these samples was compared with that of normal aggregate samples. This study revealed that there is a strong correlation among various parameters, and by measuring three of them: either 'particle density' or 'porosity and absorption' or 'particle shape', and 'strength and toughness', and 'chloride and sulphate contents', it is possible to assess the behaviour of RA. This can significantly help by reducing RA testing time and cost before using it as recycled aggregate concrete.

Comparing urban solid waste recycling from the viewpoint of urban metabolism based on physical input-output model: A case of Suzhou in China.

PubMed

Liang, Sai; Zhang, Tianzhu

2012-01-01

Investigating impacts of urban solid waste recycling on urban metabolism contributes to sustainable urban solid waste management and urban sustainability. Using a physical input-output model and scenario analysis, urban metabolism of Suzhou in 2015 is predicted and impacts of four categories of solid waste recycling on urban metabolism are illustrated: scrap tire recycling, food waste recycling, fly ash recycling and sludge recycling. Sludge recycling has positive effects on reducing all material flows. Thus, sludge recycling for biogas is regarded as an accepted method. Moreover, technical levels of scrap tire recycling and food waste recycling should be improved to produce positive effects on reducing more material flows. Fly ash recycling for cement production has negative effects on reducing all material flows except solid wastes. Thus, other fly ash utilization methods should be exploited. In addition, the utilization and treatment of secondary wastes from food waste recycling and sludge recycling should be concerned. Copyright © 2011 Elsevier Ltd. All rights reserved.

Improving information recognition and performance of recycling chimneys.

PubMed

Durugbo, Christopher

2013-01-01

The aim of this study was to assess and improve how recyclers (individuals carrying out the task of recycling) make use of visual cues to carryout recycling tasks in relation to 'recycling chimneys' (repositories for recycled waste). An initial task analysis was conducted through an activity sampling study and an eye tracking experiment using a mobile eye tracker to capture fixations of recyclers during recycling tasks. Following data collection using the eye tracker, a set of recommendations for improving information representation were then identified using the widely researched skills, rules, knowledge framework, and for a comparative study to assess the performance of improved interfaces for recycling chimneys based on Ecological Interface Design principles. Information representation on recycling chimneys determines how we recycle waste. This study describes an eco-ergonomics-based approach to improve the design of interfaces for recycling chimneys. The results are valuable for improving the performance of waste collection processes in terms of minimising contamination and increasing the quantity of recyclables.

Solid waste recycling in Rajshahi city of Bangladesh.

PubMed

Bari, Q Hamidul; Hassan, K Mahbub; Haque, M Ehsanul

2012-11-01

Efficient recycling of solid wastes is now a global concern for a sustainable and environmentally sound management. In this study, traditional recycling pattern of solid waste was investigated in Rajshahi municipality which is the fourth largest city of Bangladesh. A questionnaire survey had been carried out in various recycle shops during April 2010 to January 2011. There were 140 recycle shops and most of them were located in the vicinity of Stadium market in Rajshahi. About 1906 people were found to be involved in recycling activities of the city. The major fraction of recycled wastes were sent to capital city Dhaka for further manufacture of different new products. Only a small amount of wastes, specially plastics, were processed in local recycle factories to produce small washing pots and bottle caps. Everyday, an estimated 28.13 tons of recycled solid wastes were handled in Rajshahi city area. This recycled portion accounted for 8.25% of the daily total generated wastes (341 ton d(-1)), 54.6% of total recyclable wastes (51.49 ton d(-1)) and 68.29% of readily recyclable wastes (41.19 ton d(-1)). Major recycled materials were found to be iron, glass, plastic, and papers. Only five factories were involved in preliminary processing of recyclable wastes. Collecting and processing secondary materials, manufacturing recycled-content products, and then buying recycled products created a circle or loop that ensured the overall success of recycling and generated a host of financial, environmental, and social returns. Copyright © 2012 Elsevier Ltd. All rights reserved.

75 FR 19311 - Ocean Dumping; Guam Ocean Dredged Material Disposal Site Designation

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-14

..., landfill daily cover, and recycling into commercial products such as construction aggregate, ceramic tiles... subject its sediments to a battery of physical, chemical, and biological tests to determine suitability...

Multifunctional co-poly(amic acid): A new binder for Si-based micro-composite anode of lithium-ion battery

NASA Astrophysics Data System (ADS)

Lin, Che-Tseng; Huang, Tzu-Yang; Huang, Jau-Jiun; Wu, Nae-Lih; Leung, Man-kit

2016-10-01

Multifunctional co-poly(amic acid) (PAmA) containing pyrene and carboxylic acid side-chains is developed as a binder for the recycled kerf-loss Si-Ni-SiC composite anode. The capacity retention performance of the lithium-ion battery can be apparently enhanced. In a long-cycle test of 300 lithiation/delithiation cycles, 79% of capacity retention is achieved. In considering that the recycled kerf-loss Si sample contains 38 wt% inactive micro-sized SiC abrasive particles, the achieved capacity of 648 mAh g-1 is reasonably high in comparison to other reported values. Small anode thickness expansion of 43% is found in a 100 cycle test, reflecting that the use of the PAmA binder can create strong interconnection among the silicon particles, conductive carbons and copper electrode.

Demonstration of landfill gas enhancement techniques in landfill simulators

NASA Astrophysics Data System (ADS)

Walsh, J. J.; Vogt, W. G.

1982-02-01

Various techniques to enhance gas production in sanitary landfills were applied to landfill simulators. These techniques include (1) accelerated moisture addition, (2) leachate recycling, (3) buffer addition, (4) nutrient addition, and (5) combinations of the above. Results are compiled through on-going operation and monitoring of sixteen landfill simulators. These test cells contain about 380 kg of municipal solid waste. Quantities of buffer and nutrient materials were placed in selected cells at the time of loading. Water is added to all test cells on a monthly basis; leachate is withdrawn from all cells (and recycled on selected cells) also on a monthly basis. Daily monitoring of gas volumes and refuse temperatures is performed. Gas and leachate samples are collected and analyzed on a monthly basis. Leachate and gas quality and quantity reslts are presented for the first 18 months of operation.

Deformation Behavior of Recycled Concrete Aggregate during Cyclic and Dynamic Loading Laboratory Tests

PubMed Central

Sas, Wojciech; Głuchowski, Andrzej; Gabryś, Katarzyna; Soból, Emil; Szymański, Alojzy

2016-01-01

Recycled concrete aggregate (RCA) is a relatively new construction material, whose applications can replace natural aggregates. To do so, extensive studies on its mechanical behavior and deformation characteristics are still necessary. RCA is currently used as a subbase material in the construction of roads, which are subject to high settlements due to traffic loading. The deformation characteristics of RCA must, therefore, be established to find the possible fatigue and damage behavior for this new material. In this article, a series of triaxial cyclic loading and resonant column tests is used to characterize fatigue in RCA as a function of applied deviator stress after long-term cyclic loading. A description of the shakedown phenomenon occurring in the RCA and calculations of its resilient modulus (Mr) as a function of fatigue are also presented. Test result analysis with the stress-life method on the Wohler S-N diagram shows the RCA behavior in accordance with the Basquin law. PMID:28773905

Laboratory and Field Evaluation of In-Place Asphalt Recycling Technologies for Small Airfield Repair

DTIC Science & Technology

2013-06-01

Mariely Mejías-Santiago and William D. Carruth Geotechnical and Structures Laboratory US Army Engineer Research and Development Center 3909 Halls...24. Pavement structure at Test Site 1. ....................................................................................... 28  Figure 25. Pavement... structure at ERDC test site. ................................................................................ 30  Figure 26. Heatwurx HWX-30 electric

Industrial plastics waste: Identification and segregation

NASA Technical Reports Server (NTRS)

Widener, Edward L.

1990-01-01

Throwaway plastic products, mainly packaging, are inundating our landfills and incinerators. Most are ethenic thermoplastics, which can be recycled as new products or fossil-fuels. Lab experiments are described, involving destructive and non-destructive tests for identifying and using plastics. The burn-test, with simple apparatus and familiar samples, is recommended as quick, cheap and effective.

Effect of Recycling and Autoclave Sterilization on the Unloading Forces of NiTi Closed-Coil Springs: An In Vitro Study.

PubMed

Momeni Danaei, Sh; Oshagh, M; Khozaei, A

2013-12-01

Clinicians use the NiTi coil springs frequently for its appropriate mechanical properties. The aim of this study was to determine the effect of recycling and autoclave sterilization on the unloading forces of NiTi closed coil springs. Fourteen NiTi closed coil spring with the length of 9mm were selected. Each coil was stretched to a peak extension of 12 mm. A universal testing machine was used to acquire load/deflection curve of the coil springs at 25±2°C. The influence of thermocycling (1000 cycles,5-55°C), autoclaving (134°C, 32PSI, 3min) and mechanical strain (9mm extension) which simulated the oral condition, were considered. Data were statistically analyzed by adopting Repeated Measures MANOVA Paired t-Test. Autoclaving in the 1, 4, 6 steps increased the force levels of coil springs about 2-5gf (p< 0.01). Thermocycling reduced their force levels about 4-6gf. Prolonged strain at 3, 5 steps decreased the magnitude of forces levels about 3-4gf. Concerning all the limitations; according to the results of this study; it is possible to recycle Ni-Ti closed-coil springs without significant reduction in their force levels.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eric S. Peterson; Jessica Trudeau; Bill Cleary

An active-surface membrane technology was used to separate a die lube manufacturing wastewater stream consisting of various oils, hydrocarbons, heavy metals, and silicones. The ultrafiltration membranes reduced organics from initial oil and grease contents by 20–25X, carbon oxygen demand (COD) by 1.5 to 2X, and total organic carbon (TOC) by 0.6, while the biological oxygen demand (BOD) remained constant. The active-surface membranes were not fouled as badly as non-active-surface systems and the active-surface membrane flux levels were consistently higher and more stable than those of the non-active-surface membranes tested. Field testing demonstrated that the rotary microfilter can concentrate the diemore » lube, i.e. remove the glycerin component, and produce a die lube suitable for recycling. The recycling system operated for six weeks with only seven cleaning cycles and no mechanical or electrical failures. Test data and quality records indicate that the die casting scrap was reduced from 8.4 to 7.8%. There is no doubt that this test yielded tremendous results. This separation process presents significant opportunities that can be evaluated further.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peterson, E. S.; Trudeau, J.; Cleary, B.

An active-surface membrane technology was used to separate a die lube manufacturing wastewater stream consisting of various oils, hydrocarbons, heavy metals, and silicones. The ultrafiltration membranes reduced organics from initial oil and grease contents by 20-25X, carbon oxygen demand (COD) by 1.5 to 2X, and total organic carbon (TOC) by 0.6, while the biological oxygen demand (BOD) remained constant. The active-surface membranes were not fouled as badly as non-active-surface systems and the active-surface membrane flux levels were consistently higher and more stable than those of the non-active-surface membranes tested. Field testing demonstrated that the rotary microfilter can concentrate the diemore » lube, i.e. remove the glycerin component, and produce a die lube suitable for recycling. The recycling system operated for six weeks with only seven cleaning cycles and no mechanical or electrical failures. Test data and quality records indicate that the die casting scrap was reduced from 8.4 to 7.8%. There is no doubt that this test yielded tremendous results. This separation process presents significant opportunities that can be evaluated further.« less

Recycling in 1998: States moving forward to reach higher goals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Heumann, J.M.; Egan, K.

1998-08-01

As the end of the decade--and century--approaches, the US still is working to push the recycling envelope. The US as a whole has reached its higher recycling rate ever--27%, according to the US EPA, and individual states are striving to meet and surpass their own recycling goals. Yet, it is difficult to compare rates and goals and budgets of individual states to one another, and come up with the nationwide trend in terms of recycling. Comparing recycling programs from state to state is like comparing apples and oranges. Individual states recycle a different amount of material, include a range ofmore » materials in their recycling-rate calculations, and have a variety of costs associated with performing these activities. Recycling in New York City is nothing like recycling in Boise, Idaho, for instance. This article presents information from all 50 states and the District of Columbia on their recycling rates, goals, waste generation rates, and the resources they have allocated toward recycling efforts.« less

The effects of rare earth elements on an anaerobic hydrogen producing microorganism

NASA Astrophysics Data System (ADS)

Fujita, Y.; St Jeor, J. D.; Reed, D. W.

2016-12-01

Rapid growth of new energy technologies and consumer electronics is leading to increased fluxes of rare earth elements (REE), during the phases of resource extraction, product usage, recycling, and disposal. However, little is known about the impacts of these increased REE fluxes on environmental ecosystems, whether natural or engineered (e.g., biological waste treatment systems). We have been evaluating the effects of europium and yttrium on hydrogen production by an anaerobic fermenting microorganism, Sporacetigenium mesophilum, originally isolated from an anaerobic digester at a wastewater treatment plant.1 Europium and yttrium are important components of phosphors used in fluorescent lighting, and are expected to be recycled in larger quantities in the future. Also tested was the compound tributyl phosphate (TBP), a widely used complexing agent in lanthanide and actinide separations. TBP and related compounds may be used in recycling processes for REE. S. mesophilumcultures were amended with Eu at 100 ppb, 1 ppm and 10 ppm and hydrogen production was measured. While the lowest Eu concentration had minimal effect on hydrogen production compared to the no Eu control, the two higher Eu amendment levels appeared to enhance hydrogen production. TBP at 0.1 g/L completely inhibited hydrogen production. Measurements of aqueous Eu concentrations indicated that >85% of the added Eu remained soluble at all three of the Eu addition levels tested. Experiments to ascertain whether enhancement (or inhibition) occurs at even higher Eu concentrations are underway, as are corresponding experiments with yttrium. This work contributes to the assessment of the potential impacts of increased REE recycling and processing on ecosystems, and supports decision making with respect to disposal of wastewaters generated during these industrial practices. 1Chen, S., Song, L. and X. Dong. Int J. Syst. Evol. Microbiol. 56, 721-725, doi: 10.1099/ijs.0.63686-0 (2006).

Structural strength assessment of the reconstructed road structure in terms of the loading time and yield criterion

NASA Astrophysics Data System (ADS)

Mazurek, Grzegorz; Iwański, Marek

2018-05-01

This article reports the results of numerical simulations of the stress-strain states in the rebuilt road structure compared to the solutions contained in the Polish Catalogue, with the true characteristics of the layer materials taken into account. In the case analysed, a cold-recycled base layer with foamed bitumen as a recycling agent was used. The presented analysis is complementary to the mandatory in Poland procedure of mechanistic pavement design based on a linear elastic model. The temperature distribution in the road structure was analysed at the reference temperature of 40°C on the asphalt layer surface. The loading time was included in the computer simulations through the use of the classic generalized Maxwell model and thus the stiffness-time history of the layers had to be determined. For this purpose, the dynamic modulus E* tests of the loading time frequency from 0.1 Hz to 20 Hz were carried out, and the yield point was modelled using the Coulomb-Mohr failure criterion calculated on the basis of triaxial compression tests. The analytical solution to the problem was found with ABAQUS. The results demonstrate that the high temperature of asphalt layers and long loading time noticeably reduces the stiffness modulus in those layers. That reduction changes the principal stress levels, which significantly influences the shear stress both in the recycled base layer and in the subgrade soil. Should the yield point be exceeded rapidly in the recycled layer, the horizontal stresses in the asphalt layers will increase and adversely affect the durability of the reconstructed road pavement structure, especially in the zones of slow heavy vehicle traffic.

Comparing urban solid waste recycling from the viewpoint of urban metabolism based on physical input-output model: A case of Suzhou in China

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liang Sai, E-mail: liangsai09@gmail.com; Zhang Tianzhu, E-mail: zhangtz@mail.tsinghua.edu.cn

Highlights: Black-Right-Pointing-Pointer Impacts of solid waste recycling on Suzhou's urban metabolism in 2015 are analyzed. Black-Right-Pointing-Pointer Sludge recycling for biogas is regarded as an accepted method. Black-Right-Pointing-Pointer Technical levels of reusing scrap tires and food wastes should be improved. Black-Right-Pointing-Pointer Other fly ash utilization methods should be exploited. Black-Right-Pointing-Pointer Secondary wastes from reusing food wastes and sludge should be concerned. - Abstract: Investigating impacts of urban solid waste recycling on urban metabolism contributes to sustainable urban solid waste management and urban sustainability. Using a physical input-output model and scenario analysis, urban metabolism of Suzhou in 2015 is predicted and impactsmore » of four categories of solid waste recycling on urban metabolism are illustrated: scrap tire recycling, food waste recycling, fly ash recycling and sludge recycling. Sludge recycling has positive effects on reducing all material flows. Thus, sludge recycling for biogas is regarded as an accepted method. Moreover, technical levels of scrap tire recycling and food waste recycling should be improved to produce positive effects on reducing more material flows. Fly ash recycling for cement production has negative effects on reducing all material flows except solid wastes. Thus, other fly ash utilization methods should be exploited. In addition, the utilization and treatment of secondary wastes from food waste recycling and sludge recycling should be concerned.« less

PRESENT CONDITION OF FOOD WASTE RECYCLING LOOP BASED ON RECYCLING PROJECT CERTIFICATION OF THE FOOD WASTE RECYCLING LAW

NASA Astrophysics Data System (ADS)

Kita, Tomoko; Kanaya, Ken

Purpose of this research is to clear present condition of food waste recycling loops based on recycling project certification of the Food Waste Recycling Law. Method of this research is questionnaire survey to companies constituting the loops. Findings of this research are as follows: 1. Proponents of the loop is most often the recycling companies. 2. Food waste recycling rate is 61% for the food retailing industry and 81% for the food service industry. These values are higher than the national average in 2006. The effect of the revision of recycling project certification is suggested.

3 CFR 8601 - Proclamation 8601 of November 15, 2010. America Recycles Day, 2010

Code of Federal Regulations, 2011 CFR

2011-01-01

... planet, participating in curbside recycling and community composting programs, and expanding their use of recyclable and recycled materials. Recycling not only preserves our environment by conserving precious... development. This billion-dollar industry employs thousands of workers nationwide, and evolving our recycling...

Rab15 Effector Protein: A Novel Protein for Receptor Recycling from the Endocytic Recycling CompartmentD⃞

PubMed Central

Strick, David J.; Elferink, Lisa A.

2005-01-01

Sorting endosomes and the endocytic recycling compartment are critical intracellular stores for the rapid recycling of internalized membrane receptors to the cell surface in multiple cell types. However, the molecular mechanisms distinguishing fast receptor recycling from sorting endosomes and slow receptor recycling from the endocytic recycling compartment remain poorly understood. We previously reported that Rab15 differentially regulates transferrin receptor trafficking through sorting endosomes and the endocytic recycling compartment, suggesting a role for distinct Rab15-effector interactions at these endocytic compartments. In this study, we identified the novel protein Rab15 effector protein (REP15) as a binding partner for Rab15-GTP. REP15 is compartment specific, colocalizing with Rab15 and Rab11 on the endocytic recycling compartment but not with Rab15, Rab4, or early endosome antigen 1 on sorting endosomes. REP15 interacts directly with Rab15-GTP but not with Rab5 or Rab11. Consistent with its localization, REP15 overexpression and small interfering RNA-mediated depletion inhibited transferrin receptor recycling from the endocytic recycling compartment, without affecting receptor entry into or recycling from sorting endosomes. Our data identify REP15 as a compartment-specific protein for receptor recycling from the endocytic recycling compartment, highlighting that the rapid and slow modes of transferrin receptor recycling are mechanistically distinct pathways. PMID:16195351

Microbiological Tests Performed During the Design of the International Space Station ECLSS: Part 1, Bulk Phase Water and Wastewater

NASA Technical Reports Server (NTRS)

Roman, Monsi C.; Mittelman, Marc W.

2010-01-01

This slide presentation summarizes the studies performed to assess the bulk phase microbial community during the Space Station Water Recover Tests (WRT) from 1990-1998. These tests show that it is possible to recycle water from different sources including urine, and produce water that can exceed the quality of municpally produced tap water.

Utilizing Lab Tests to Predict Asphalt Concrete Overlay Performance

DOT National Transportation Integrated Search

2017-12-01

A series of five experimental projects and three demonstration projects were constructed to better understand the performance of pavement overlays using various levels of asphalt binder replacement (ABR) from reclaimed asphalt pavement (RAP), recycle...

Recycling research progress at the Forest Products Laboratory.

Treesearch

1995-01-01

This document summarizes accomplishments of USDA Forest Service researchers in the area of recycling. Specifically, it describes work in economic assessment, paper recycling, recycled housing and industrial applications of recycled materials, other recycling applications, and technology transfer. The literature list includes the references cited in the text and...

Recycling Lesson Plan

ERIC Educational Resources Information Center

Okaz, Abeer Ali

2013-01-01

This lesson plan designed for grade 2 students has the goal of teaching students about the environmental practice of recycling. Children will learn language words related to recycling such as: "we can recycle"/"we can't recycle" and how to avoid littering with such words as: "recycle paper" and/or "don't throw…

EFFECTS OF NUMBER AND LOCATION OF BINS ON PLASTIC RECYCLING AT A UNIVERSITY

PubMed Central

O'Connor, Ryan T; Lerman, Dorothea C; Fritz, Jennifer N; Hodde, Henry B

2010-01-01

The proportion of plastic bottles that consumers placed in appropriate recycling receptacles rather than trash bins was examined across 3 buildings on a university campus. We extended previous research on interventions to increase recycling by controlling the number of recycling receptacles across conditions and by examining receptacle location without the use of posted signs. Manipulating the appearance or number of recycling bins in common areas did not increase recycling. Consumers recycled substantially more plastic bottles when the recycling bins were located in classrooms. PMID:21541154

Effects of number and location of bins on plastic recycling at a university.

PubMed

O'Connor, Ryan T; Lerman, Dorothea C; Fritz, Jennifer N; Hodde, Henry B

2010-01-01

The proportion of plastic bottles that consumers placed in appropriate recycling receptacles rather than trash bins was examined across 3 buildings on a university campus. We extended previous research on interventions to increase recycling by controlling the number of recycling receptacles across conditions and by examining receptacle location without the use of posted signs. Manipulating the appearance or number of recycling bins in common areas did not increase recycling. Consumers recycled substantially more plastic bottles when the recycling bins were located in classrooms.

Experimental research on durability of recycled aggregate concrete under freeze- thaw cycles

NASA Astrophysics Data System (ADS)

Cheng, Yanqiu; Shang, Xiaoyu; Zhang, Youjia

2017-07-01

The freeze-thaw durability of recycled aggregate concrete has significance for the concrete buildings in the cold region. In this paper, the rapid freezing and thawing cycles experience on recycle aggregate concrete was conducted to study on the effects of recycle aggregate amount, water-binder ratio and fly ash on freeze-thaw durability of recycle aggregate concrete. The results indicates that recycle aggregate amount makes the significant influence on the freeze-thaw durability. With the increase of recycled aggregates amount, the freeze-thaw resistance for recycled aggregate concrete decreases. Recycled aggregate concrete with lower water cement ratio demonstrates better performance of freeze-thaw durability. It is advised that the amount of fly ash is less than 30% for admixture of recycled aggregates in the cold region.

Comparisons of four categories of waste recycling in China's paper industry based on physical input-output life-cycle assessment model.

PubMed

Liang, Sai; Zhang, Tianzhu; Xu, Yijian

2012-03-01

Waste recycling for paper production is an important component of waste management. This study constructs a physical input-output life-cycle assessment (PIO-LCA) model. The PIO-LCA model is used to investigate environmental impacts of four categories of waste recycling in China's paper industry: crop straws, bagasse, textile wastes and scrap paper. Crop straw recycling and wood utilization for paper production have small total intensity of environmental impacts. Moreover, environmental impacts reduction of crop straw recycling and wood utilization benefits the most from technology development. Thus, using crop straws and wood (including wood wastes) for paper production should be promoted. Technology development has small effects on environmental impacts reduction of bagasse recycling, textile waste recycling and scrap paper recycling. In addition, bagasse recycling and textile waste recycling have big total intensity of environmental impacts. Thus, the development of bagasse recycling and textile waste recycling should be properly limited. Other pathways for reusing bagasse and textile wastes should be explored and evaluated. Moreover, imports of scrap paper should be encouraged to reduce large indirect impacts of scrap paper recycling on domestic environment. Copyright © 2011 Elsevier Ltd. All rights reserved.

Educating T-Shaped professionals to meet substitution challenges and developing business models for substitution and recycling

NASA Astrophysics Data System (ADS)

Arroyo, Ana; Mendibil Eguiluz, Javier; Sánchez Cupido, Laura

2018-03-01

One strategy to overcome the challenges related to critical raw materials (CRMs) is their substitution and recycling. However, the bright scientific idea, proof of concept or laboratory demonstration need to cross the valley of death in order to become stated as ‘a substitute’ instead of ‘a potential substitute’. Most PhD students and Post Docs specialize within a given thematic area; for example on specific materials or on substitution in a certain application. This specialization could limit the ability to generate innovations and profitable business models if there are not enough tools and skills to transform new knowledge and research results into an appealing value proposition towards customers and to a business opportunity for the current markets. The project proposes a framework for developing substitution and recycling related cross-sectorial skills and tools. These are applied for training business-related competences e.g. teamwork, management, communication, value proposition and business models design, especially within RTOs and industries. The proposed learning itinerary can radically improve the path from scientific proof of concept into innovation and lean start up or industrial market launch. The developed framework is tested by a pilot group having several topics within the areas of substitution and recycling of critical raw materials.

Recycling of plastic wastes with poly (ethylene-co-methacrylic acid) copolymer as compatibilizer and their conversion into high-end product.

PubMed

Rajasekaran, Divya; Maji, Pradip K

2018-04-01

This paper deals with the utilization of plastic wastes to a useful product. The major plastic pollutants that are considered to be in maximum use i.e. PET bottle and PE bags have been taken for consideration for recycling. As these two plastic wastes are not compatible, poly (ethylene-co-methacrylic acid) copolymer has been used as compatibilizer to process these two plastic wastes. Effect of dose of poly (ethylene-co-methacrylic acid) copolymer as compatibilizer has been studied here. It has been shown that only 3 wt% of poly (ethylene-co-methacrylic acid) copolymer is sufficient to make 3:1 mass ratio of PET bottle and polyethylene bags compatible. Compatibility has been examined through mechanical testing, thermal and morphological analysis. After analysing the property of recyclates, better mechanical and thermal property has been observed. Almost 500% of tensile property has been improved by addition of 3 wt% of poly (ethylene-co-methacrylic acid) copolymer in 3:1 mass ratio blend of PET bottle and PE bags than that of pristine blend. Morphological analysis by FESEM and AFM has also confirmed the compatibility of the blend. Experimental data showed better performance than available recycling process. Copyright © 2018 Elsevier Ltd. All rights reserved.

Effect of crumb rubber on the mechanical properties of crushed recycled pavement materials.

PubMed

Li, Jie; Saberian, Mohammad; Nguyen, Bao Thach

2018-07-15

The low-carbon footprint of using recycled construction and demolition (C&D) aggregates in civil engineering infrastructure applications has been considered to be a significant solution for the replacement of conventional pavement aggregates. Investigations regarding the use of crumb rubber in the base and subbase layers of pavement have been well documented. However, information on the effects of crumb rubber and its size within C&D aggregates as the base/subbase layers is still very limited. In this study, crumb rubber with particle sizes ranging from 400 to 600 μm (fine) to 10-15 mm (coarse), 20 mm recycled crushed concrete (RCC), and 20 mm crushed rock (CR) were used. The crumb rubber was added to the two groups of C&D aggregates at 0.5, 1 and 2% by weight percentages of the aggregates. The effect of crumb rubber on the mechanical properties (such as California bearing ratio, unconfined compressive strength, aggregate crushing value, dynamic lightweight cone penetrometer, Clegg impact value, Los Angeles abrasion values, and resilient modulus) of the C&D aggregates was then examined. Based on the experimental test results, it was found that crumb rubber can be recycled as a waste material for the base and subbase layers in the pavement. Copyright © 2018 Elsevier Ltd. All rights reserved.

Light weight and high strength materials made of recycled steel and aluminum

NASA Astrophysics Data System (ADS)

Nounezi, Thomas

Recycling has proven not only to address today's economical, environmental and social issues, but also to be imperative for the sustainability of human technology. The current thesis has investigated the feasibility of a new philosophy for Recycling (Alloying-Recycling) using steel 1020 and aluminum 6061T6. The study was limited to the metallurgical aspects only and has highlighted the potential of recycled alloys made of recycled aluminum and steel to exhibit substantially increased wear resistance and strength-to-weight ratio as compared to initial primary materials. Three alloy-mixtures are considered: TN3 (5wt% 1020 +95wt% 6061T6); TN5 (0.7wt% 1020 + 99.3wt% 6061T6); and TN4 (10wt% 6061T6 + 90wt% 1020). A Tucker induction power supply system (3kW; 135-400 kHz) is used to melt the alloy mixtures for casting in graphite crucibles. Heat treatment of the cast samples is done using a radiation box furnace. Microscopy, Vickers hardness and pin-on-disc abrasive wear tests are performed. Casting destroyed the initial microstructures of the alloys leading to a hardness reduction in the as-cast and solution heat-treated aluminum rich samples to 60 Hv from 140 Hv. Ageing slightly increased the hardness of the cast samples and provided a wear resistance two times higher than that of the initial 6061T6 material. On the steel rich side, the hardness of the as-cast TN4 was 480 Hv, which is more than twice as high as the initial hardness of steel 1020 of 202 Hv; this hints to strong internal and residual stress, probably martensite formation during fast cooling following casting. Solution heat treatment lowered the hardness to the original value of steel 1020, but provided about ten (10) times higher wear resistance; this suggests higher ductility and toughness of normalised TN4 as compared to 1020. In addition, TN4 exhibits about 25% weight reduction as compared to 1020. The actual recycling process and the effect of non-metallic impurities shall be investigated in future works. Also, the casting and heat treatment processes need to be improved.

Wee Recyclers. An Activity Guide for Ages 3-5.

ERIC Educational Resources Information Center

Wisconsin State Dept. of Natural Resources, Madison.

Recycling and reusing are skills that can be developed in early child care programs. This activity guide is intended to help teach children (ages 3-5) about recycling using simple, hands-on activities. Teacher-directed activities involve setting up a recycling center, sorting recyclable items, landfills, litter, a recycling alphabet, and ways that…

Sorting Recycled Trash: An Activity for Earth Day 2007

ERIC Educational Resources Information Center

Harris, Mary E.; Harris, Harold H.

2007-01-01

Middle or high school students celebrate Earth Day on April 22, 2007 by participating in the activity to separate commingled recyclable trash to simulate sorting in a recycling center. Students would gain an appreciation for recyclable trash, after it is taken to a recycling center and learn about properties of recyclables.

Crucial role of neuron-enriched endosomal protein of 21 kDa in sorting between degradation and recycling of internalized G-protein-coupled receptors.

PubMed

Debaigt, Colin; Hirling, Harald; Steiner, Pascal; Vincent, Jean-Pierre; Mazella, Jean

2004-08-20

Recycling of endocytosed G-protein-coupled receptors involves a series of molecular events through early and recycling endosomes. The purpose of this work was to study the role of neuron-enriched endosomal protein of 21 kDa (NEEP21) in the recycling process of neurotensin receptors-1 and -2. Here we showed that suppression of NEEP21 expression does not modify the internalization rate of both receptors but strongly inhibited the recycling of the neurotensin receptor-2. In contrast, overexpression of NEEP21 changes the behavior of the neurotensin receptor-1 from a non-recycling to a recycling state. Recycling of the neurotensin receptor-2 involves both the phosphatidylinositol 3-kinase and the recycling endosome pathways, whereas recycling of the neurotensin receptor-1 induced by overexpression of NEEP21 only occurs by the phosphatidylinositol 3-kinase-dependent pathway. Taken together, these results confirm the essential role of NEEP21 in the recycling mechanism and show that this protein acts at the level of early endosomes to promote sorting of receptors toward a recycling pathway.

A Factorial Design Approach to Analyse the Effect of Coarse Recycled Concrete Aggregates on the Properties of Hot Mix Asphalt

NASA Astrophysics Data System (ADS)

Tanty, Kiranbala; Mukharjee, Bibhuti Bhusan; Das, Sudhanshu Shekhar

2018-06-01

The present study investigates the effect of replacement of coarse fraction of natural aggregates by recycled concrete aggregates on the properties of hot mix asphalt (HMA) using general factorial design approach. For this two factors i.e. recycled coarse aggregates percentage [RCA (%)] and bitumen content percentage [BC (%)] are considered. Tests have been carried out on the HMA type bituminous concrete, prepared with varying RCA (%) and BC (%). Analysis of variance has been performed on the experimental data to determine the effect of the chosen factors on various parameters such as stability, flow, air void, void mineral aggregate, void filled with bitumen and bulk density. The study depicts that RCA (%) and BC (%) have significant effect on the selected responses as p value is less than the chosen significance level. In addition to above, the outcomes of the statistical analysis indicate that interaction between factors have significant effects on void mineral aggregate and bulk density of bituminous concrete.

Electrochemical disinfection of repeatedly recycled blackwater in a free‐standing, additive‐free toilet

PubMed Central

Sellgren, Katelyn L.; Klem, Ethan J. D.; Piascik, Jeffrey R.; Stoner, Brian R.

2017-01-01

Abstract Decentralized, energy‐efficient waste water treatment technologies enabling water reuse are needed to sustainably address sanitation needs in water‐ and energy‐scarce environments. Here, we describe the effects of repeated recycling of disinfected blackwater (as flush liquid) on the energy required to achieve full disinfection with an electrochemical process in a prototype toilet system. The recycled liquid rapidly reached a steady state with total solids reliably ranging between 0.50 and 0.65% and conductivity between 20 and 23 mS/cm through many flush cycles over 15 weeks. The increase in accumulated solids was associated with increased energy demand and wide variation in the free chlorine contact time required to achieve complete disinfection. Further studies on the system at steady state revealed that running at higher voltage modestly improves energy efficiency, and established running parameters that reliably achieve disinfection at fixed run times. These results will guide prototype testing in the field. PMID:29242713

A Factorial Design Approach to Analyse the Effect of Coarse Recycled Concrete Aggregates on the Properties of Hot Mix Asphalt

NASA Astrophysics Data System (ADS)

Tanty, Kiranbala; Mukharjee, Bibhuti Bhusan; Das, Sudhanshu Shekhar

2018-02-01

The present study investigates the effect of replacement of coarse fraction of natural aggregates by recycled concrete aggregates on the properties of hot mix asphalt (HMA) using general factorial design approach. For this two factors i.e. recycled coarse aggregates percentage [RCA (%)] and bitumen content percentage [BC (%)] are considered. Tests have been carried out on the HMA type bituminous concrete, prepared with varying RCA (%) and BC (%). Analysis of variance has been performed on the experimental data to determine the effect of the chosen factors on various parameters such as stability, flow, air void, void mineral aggregate, void filled with bitumen and bulk density. The study depicts that RCA (%) and BC (%) have significant effect on the selected responses as p value is less than the chosen significance level. In addition to above, the outcomes of the statistical analysis indicate that interaction between factors have significant effects on void mineral aggregate and bulk density of bituminous concrete.

Design of mechanical arm for an automatic sorting system of recyclable cans

NASA Astrophysics Data System (ADS)

Resti, Y.; Mohruni, A. S.; Burlian, F.; Yani, I.; Amran, A.

2018-04-01

The use of a mechanical arm for an automatic sorting system of used cans should be designed carefully. The right design will result in a high precision sorting rate and a short sorting time. The design includes first; design manipulator,second; determine link and joint specifications, and third; build mechanical systems and control systems. This study aims to design the mechanical arm as a hardware system for automatic cans sorting system. The material used for the manipulator is the aluminum plate. The manipulator is designed using 6 links and 6 join where the 6th link is the end effectorand the 6th join is the gripper. As a driving motor used servo motor, while as a microcontroller used Arduino Uno which is connected with Matlab programming language. Based on testing, a mechanical arm designed for this recyclable canned recycling system has a precision sorting rate at 93%, where the average total time required for sorting is 10.82 seconds.

Montmorillonite-supported Ag/TiO(2) nanoparticles: an efficient visible-light bacteria photodegradation material.

PubMed

Wu, Tong-Shun; Wang, Kai-Xue; Li, Guo-Dong; Sun, Shi-Yang; Sun, Jian; Chen, Jie-Sheng

2010-02-01

Montmorillonite (MMT)-supported Ag/TiO(2) composite (Ag/TiO(2)/MMT) has been prepared through a one-step, low-temperature solvothermal technique. Powder X-ray diffraction (XRD) and transmission electron microscopy (TEM) reveal that the Ag particles coated with TiO(2) nanoparticles are well-dispersed on the surface of MMT in the composite. As a support for the Ag/TiO(2) composite, the MMT prevents the loss of the catalyst during recycling test. This Ag/TiO(2)/MMT composite exhibits high photocatalytic activity and good recycling performance in the degradation of E. coli under visible light. The high visible-light photocatalytic activity of the Ag/TiO(2)/MMT composite is ascribed to the increase in surface active centers and the localized surface plasmon effect of the Ag nanoparticles. The Ag/TiO(2)/MMT materials with excellent stability, recyclability, and bactericidal activities are promising photocatalysts for application in decontamination.

Performance of high-recovery recycling reverse osmosis with wash water

NASA Technical Reports Server (NTRS)

Herrmann, Cal C.

1993-01-01

Inclusion of a recycling loop for partially-desalted water from second-stage reverse-osmosis permeate has been shown useful for achieving high-recovery at moderate applied pressures. This approach has now been applied to simulated wash waters, to obtain data on retention by the membranes of solutes in a mixture comparable to anticipated spacecraft hygiene wastewaters, and to generate an estimate of the maximum concentration that can be expected without causing membrane fouling. A first experiment set provides selectivity information from a single membrane and an Igepon detergent, as a function of final concentration. A reject concentration of 3.1% Total Organic Carbon has been reached, at a pressure of 1.4 Mega Pascals, without membrane fouling. Further experiments have generated selectivity values for the recycle configuration from two washwater simulations, as a function of applied pump pressure. Reverse osmosis removal has also been tested for washwater containing detergent formulated for plant growth compatibility (containing nitrogen, phosphorous and potassium functional groups.)

Soldering mask laser removal from printed circuit boards aiming copper recycling.

PubMed

Raele, Marcus Paulo; De Pretto, Lucas Ramos; Zezell, Denise Maria

2017-10-01

Management of waste of electric and electronic equipment (WEEE) is a key issue for modern societies; furthermore, it contains valuable materials that can be recycled, especially in printed circuit boards (PCB), which have approximately one-third of their weight in copper. In this study we demonstrated the use of laser to strip the covering soldering mask on PCB's, thus exposing the copper underneath so that extraction techniques may take place. Using a Q-Switched Nd:YAG laser operating at 1064nm and 532nm we tested the procedure under different energy conditions. The laser stripping of the soldering mask was achieved with satisfactory results by irradiation with 225mJ at 1064nm. However, when using similar parameters at 532nm the process of the coating ejection was not promoted properly, leading to a faulty detachment. Infrared laser PCB stripping presents itself to be technically viable and environmental friendly, since it uses no chemicals inputs, offering one more option to WEEE treatment and recycling. Copyright © 2017 Elsevier Ltd. All rights reserved.

Auditing Operating Room Recycling: A Management Case Report.

PubMed

McGain, Forbes; Jarosz, Katherine Maria; Nguyen, Martin Ngoc Hoai Huong; Bates, Samantha; O'Shea, Catherine Jane

2015-08-01

Much waste arises from operating rooms (ORs). We estimated the practical and financial feasibility of an OR recycling program, weighing all waste from 6 ORs in Melbourne, Australia. Over 1 week, 237 operations produced 1265 kg in total: general waste 570 kg (45%), infectious waste 410 kg (32%), and recyclables 285 kg (23%). The achieved recycling had no infectious contamination. The achieved recycling/potential recycling rate was 285 kg/517 kg (55%). The average waste disposal costs were similar for general waste and recycling. OR recycling rates of 20%-25% total waste were achievable without compromising infection control or financial constraints.

Characterization of plastic blends made from mixed plastics waste of different sources.

PubMed

Turku, Irina; Kärki, Timo; Rinne, Kimmo; Puurtinen, Ari

2017-02-01

This paper studies the recyclability of construction and household plastic waste collected from local landfills. Samples were processed from mixed plastic waste by injection moulding. In addition, blends of pure plastics, polypropylene and polyethylene were processed as a reference set. Reference samples with known plastic ratio were used as the calibration set for quantitative analysis of plastic fractions in recycled blends. The samples were tested for the tensile properties; scanning electron microscope-energy-dispersive X-ray spectroscopy was used for elemental analysis of the blend surfaces and Fourier transform infrared (FTIR) analysis was used for the quantification of plastics contents.

Beyond the Egg Carton Alligator: To Recycle Is To Recall and Restore.

ERIC Educational Resources Information Center

Congdon, Kristin G.

2000-01-01

States that the art of recycling has more to do with connecting people with objects, traditions, and rituals than sustaining the natural environment. Discusses some lessons learned in four categories: (1) recycling as self-sufficiency; (2) recycling as renewal; (3) recycling as a spiritual activity; and (4) recycling as aesthetic transformation.…

QuEST: Qualifying Environmentally Sustainable Technologies

NASA Technical Reports Server (NTRS)

Lewis, Pattie

2012-01-01

Articles in this issue inlude: (1) Foundation of Technology Evaluation for Environmental Risk Mitigation Principal Center (TEERM) Technology Evaluation is Testing and Qualification, (2) Materials Management and Substitution Efforts, (3 Recycling and Pollution Control Efforts, and (4) Remediation Efforts

Heat release rate of wood-plastic composites

Treesearch

N. M. Stark; R. H. White; C. M. Clemons

1997-01-01

Wood-plastic composites are becoming more important as a material that fulfills recycling needs. In this study, fire performance tests were conducted on several compositions of wood and plastic materials using the Ohio State University rate of heat release apparatus. Test results included five-minute average heat release rate in kW/m2 (HRR avg) and maximum heat release...

Methane Post-Processor Development to Increase Oxygen Recovery beyond State-of-the-Art Carbon Dioxide Reduction Technology

NASA Technical Reports Server (NTRS)

Abney, Morgan; Miller, Lee; Greenwood, Zach; Iannantuono, Michelle; Jones, Kenny

2013-01-01

State-of-the-art life support carbon dioxide (CO2) reduction technology, based on the Sabatier reaction, is theoretically capable of 50% recovery of oxygen from metabolic CO2. This recovery is constrained by the limited availability of reactant hydrogen. Post-processing of the methane byproduct from the Sabatier reactor results in hydrogen recycle and a subsequent increase in oxygen recovery. For this purpose, a Methane Post-Processor Assembly containing three sub-systems has been developed and tested. The assembly includes a Methane Purification Assembly (MePA) to remove residual CO2 and water vapor from the Sabatier product stream, a Plasma Pyrolysis Assembly (PPA) to partially pyrolyze methane into hydrogen and acetylene, and an Acetylene Separation Assembly (ASepA) to purify the hydrogen product for recycle. The results of partially integrated testing of the sub-systems are reported.

Methane Post-Processor Development to Increase Oxygen Recovery beyond State-of-the-Art Carbon Dioxide Reduction Technology

NASA Technical Reports Server (NTRS)

Abney, Morgan B.; Greenwood, Zachary; Miller, Lee A.; Alvarez, Giraldo; Iannantuono, Michelle; Jones, Kenny

2013-01-01

State-of-the-art life support carbon dioxide (CO2) reduction technology, based on the Sabatier reaction, is theoretically capable of 50% recovery of oxygen from metabolic CO2. This recovery is constrained by the limited availability of reactant hydrogen. Post-processing of the methane byproduct from the Sabatier reactor results in hydrogen recycle and a subsequent increase in oxygen recovery. For this purpose, a Methane Post-Processor Assembly containing three sub-systems has been developed and tested. The assembly includes a Methane Purification Assembly (MePA) to remove residual CO2 and water vapor from the Sabatier product stream, a Plasma Pyrolysis Assembly (PPA) to partially pyrolyze methane into hydrogen and acetylene, and an Acetylene Separation Assembly (ASepA) to purify the hydrogen product for recycle. The results of partially integrated testing of the sub-systems are reported

Complex deformation routes for direct recycling aluminium alloy scrap via industrial hot extrusion

NASA Astrophysics Data System (ADS)

Paraskevas, Dimos; Kellens, Karel; Kampen, Carlos; Mohammadi, Amirahmad; Duflou, Joost R.

2018-05-01

This paper presents the final results of an industrial project, aiming for direct hot extrusion of wrought aluminium alloy scrap at an industrial scale. Two types of complex deformation/extrusion routes were tested for the production of the same profile, starting from AA6060 scrap in form of machining chips. More specifically scrap-based billets were extruded through: a 2-porthole and a 4-porthole die-set, modified for enhanced scrap consolidation and grain refinement. For comparison reasons, cast billets of the same alloy were extruded through the modified 2-porthole die set. The tensile testing results as well as microstructural investigations show that the 4-porthole extrusion route further improves scrap consolidation compared to the 2-porthole die output. The successful implementation of solid state recycling, directly at industrial level, indicates the technological readiness level of this research.

Biofilms and the survival of opportunistic pathogens in recycled water

NASA Technical Reports Server (NTRS)

Boyle, M.; Ford, T.; Maki, J. S.; Mitchell, R.

1991-01-01

Microorganisms are likely to develop an organic film on pipes, water reservoirs and filters used for waste water reclamation during extended missions in space. These biofilms can serve to protect and concentrate potentially pathogenic microorganisms. Our investigation has emphasized the survival strategy of opportunistic pathogenic bacteria in distilled water. Pseudomonas aeruginosa and Staphylococcus aureus were used as test organisms. Cultures were incubated at 10 degrees, 25 degrees, and 37 degrees C. No viable Staphylococcus cells were detected after the first week of incubation. P. aeruginosa, however, survived in distilled water up to 5 months at all three temperatures tested. The starved cells were able to form a biofilm layer on stainless steel. The cells exhibited a negative surface charge. The charge may be involved in the adhesion of this bacterium to metal substrata. We are currently investigating the importance of adhesion in the survival of this and other potential human pathogens found in water recycling systems.

Case study: apparel industry waste management: a focus on recycling in South Africa.

PubMed

Larney, M; van Aardt, A M

2010-01-01

The need for effective apparel waste management is motivated by the increasing cost and decreasing availability of landfill space and the dwindling of natural resources. The aim of this study was to identify the current solid waste disposal and recycling practices of the apparel industry in South Africa and to determine their attitude and willingness towards recycling, their perception of the feasibility thereof, barriers to recycling and marketing strategies that would be appropriate for products made from recycled materials. A structured questionnaire was mailed to apparel manufacturers in South Africa. The results indicated that most apparel manufacturers use landfills to dispose of their waste, while approximately half recycle some of the waste. They are fairly positive towards recycling, with consideration of economical feasibility. Phi-coefficients show no practically significant relationship between company size and the use of recycled materials. The most important barriers to recycling are lack of equipment and technology, lack of material to recycle and lack of consumer awareness. Marketing strategies for recycled products are recommended. It is concluded that consumer awareness and knowledge regarding recycled apparel products should be developed in order to ensure a market and that apparel manufacturers should be encouraged to recycle more extensively, in order to ensure that resources will not be exhausted unnecessarily and the environment will be preserved optimally.

16 CFR 300.18 - Use of name of specialty fiber.

Code of Federal Regulations, 2013 CFR

2013-01-01

... designation permitted under this rule: 55% Alpaca—45% Camel Hair 50% Recycled Camel Hair—50% Wool 60% Recycled Alpaca—40% Rayon 35% Recycled Llama—35% Recycled Vicuna—30% Cotton 60% Cotton—40% Recycled Llama. (b...

16 CFR 300.18 - Use of name of specialty fiber.

Code of Federal Regulations, 2014 CFR

2014-01-01

... designation permitted under this rule: 55% Alpaca—45% Camel Hair 50% Recycled Camel Hair—50% Wool 60% Recycled Alpaca—40% Rayon 35% Recycled Llama—35% Recycled Vicuna—30% Cotton 60% Cotton—40% Recycled Llama. (b...

16 CFR 300.18 - Use of name of specialty fiber.

Code of Federal Regulations, 2010 CFR

2010-01-01

... designation permitted under this rule: 55% Alpaca—45% Camel Hair 50% Recycled Camel Hair—50% Wool 60% Recycled Alpaca—40% Rayon 35% Recycled Llama—35% Recycled Vicuna—30% Cotton 60% Cotton—40% Recycled Llama. (b...

16 CFR 300.18 - Use of name of specialty fiber.

Code of Federal Regulations, 2012 CFR

2012-01-01

... designation permitted under this rule: 55% Alpaca—45% Camel Hair 50% Recycled Camel Hair—50% Wool 60% Recycled Alpaca—40% Rayon 35% Recycled Llama—35% Recycled Vicuna—30% Cotton 60% Cotton—40% Recycled Llama. (b...

Analyzing effective municipal solid waste recycling programs: the case of county-level MSW recycling performance in Florida, USA.

PubMed

Park, Seejeen; Berry, Frances S

2013-09-01

Municipal solid waste (MSW) recycling performance, both nationally and in Florida, USA, has shown little improvement during the past decade. This research examines variations in the MSW recycling program performance in Florida counties in an attempt to identify effective recycling programs. After reviewing trends in the MSW management literature, we conducted an empirical analysis using cross-sectional multiple regression analysis. The findings suggest that the convenience-based hypothesis was supported by showing that curbside recycling had a positive effect on MSW recycling performance. Financial (cost-saving) incentive-based hypotheses were partially supported meaning that individual level incentives can influence recycling performance. Citizen environmental concern was found to positively affect the amount of county recycling, while education and political affiliation yielded no significant results. In conclusion, this article discusses the implications of the findings for both academic research and practice of MSW recycling programs.

The development and prospects of the end-of-life vehicle recycling system in Taiwan.

PubMed

Chen, Kuan-chung; Huang, Shih-han; Lian, I-wei

2010-01-01

Automobiles usually contain toxic substances, such as lubricants, acid solutions and coolants. Therefore, inappropriate handling of end-of-life vehicles (ELVs) will result in environmental pollution. ELV parts, which include metallic and non-metallic substances, are increasingly gaining recycling value due to the recent global shortage of raw materials. Hence, the establishment of a proper recycling system for ELVs will not only reduce the impact on the environment during the recycling process, but it will also facilitate the effective reuse of recycled resources. Prior to 1994, the recycling of ELVs in Taiwan was performed by related operators in the industry. Since the publishing of the "End-of-life vehicle recycling guidelines" under the authority of the Waste Disposal Act by the Environmental Protection Administration (EPA) in 1994, the recycling of ELVs in Taiwan has gradually become systematic. Subsequently, the Recycling Fund Management Board (RFMB) of the EPA was established in 1998 to collect a Collection-Disposal-Treatment Fee (recycling fee) from responsible enterprises for recycling and related tasks. Since then, the recycling channels, processing equipment, and techniques for ELVs in Taiwan have gradually become established. This paper reviews the establishment of the ELV recycling system, analyzes the current system and its performance, and provides some recommendations for future development. The reduction of auto shredder residue (ASR) is a key factor in maximizing the resource recovery rate and recycling efficiency. The RFMB needs to provide strong economic incentives to further increase the recycling rate and to encourage the automobile industry to design and market greener cars. 2010 Elsevier Ltd. All rights reserved.

Recycling Lesson Plans.

ERIC Educational Resources Information Center

Pennsylvania State Dept. of Environmental Resources, Harrisburg.

This document contains lesson plans about recycling for teachers in grades K-12. Titles include: (1) "Waste--Where Does It Come From? Where Does It Go?" (2) "Litter Detectives," (3) "Classroom Paper Recycling," (4) "Recycling Survey," (5) "Disposal and Recycling Costs," (6) "Composting…

Recycling at Penn State's Beaver Stadium. "Recycle on the Go" Success Story

ERIC Educational Resources Information Center

US Environmental Protection Agency, 2009

2009-01-01

With a 13-year-old recycling program, The Pennsylvania State University's (Penn State) Beaver Stadium in the past diverted nearly 30 tons of recyclables per year from local landfills. A new initiative to promote recycling in the stadium's tailgating area has helped Penn State more than triple its old recycling record, collecting 112 tons in 2008.…

Probabilistic Analysis of Structural Member from Recycled Aggregate Concrete

NASA Astrophysics Data System (ADS)

Broukalová, I.; Šeps, K.

2017-09-01

The paper aims at the topic of sustainable building concerning recycling of waste rubble concrete from demolition. Considering demands of maximising recycled aggregate use and minimising of cement consumption, composite from recycled concrete aggregate was proposed. The objective of the presented investigations was to verify feasibility of the recycled aggregate cement based fibre reinforced composite in a structural member. Reliability of wall from recycled aggregate fibre reinforced composite was assessed in a probabilistic analysis of a load-bearing capacity of the wall. The applicability of recycled aggregate fibre reinforced concrete in structural applications was demonstrated. The outcomes refer to issue of high scatter of material parameters of recycled aggregate concretes.

North of the 46° parallel: Obstacles and challenges to recycling in Ontario's rural and northern communities.

PubMed

Lakhan, Calvin

2015-10-01

This study examines the economic challenges of recycling in Ontario's rural and northern areas. Specifically, this study quantifies the economic and diversion impact of operating recycling programs in these regions. Using a systems based cost model, focus is placed on analyzing: (1) What would happen to provincial recycling costs and diversion levels if recycling programs were eliminated in "high cost" northern and rural communities? (2) Is it possible to increase the provincial recycling rate by focusing investments in low cost, high performance regions (while simultaneously eliminating recycling programs in rural and northern areas)? (3) How would the mix of material recovered change if recycling programs were eliminated in rural and northern areas? The results of this analysis show that eliminating recycling programs in high cost regions significantly decreased system costs without negatively impacting overall recycling rates. This study also found that it was possible to increase the provincial recycling rate while simultaneously reducing program costs by targeting specific regions for recovery. The findings of this study suggest that Ontario reevaluate whether rural and northern municipalities be legislatively required to operate household recycling programs. Copyright © 2015 Elsevier Ltd. All rights reserved.

Electric vehicle recycling 2020: Key component power electronics.

PubMed

Bulach, Winfried; Schüler, Doris; Sellin, Guido; Elwert, Tobias; Schmid, Dieter; Goldmann, Daniel; Buchert, Matthias; Kammer, Ulrich

2018-04-01

Electromobility will play a key role in order to reach the specified ambitious greenhouse gas reduction targets in the German transport sector of 42% between 1990 and 2030. Subsequently, a significant rise in the sale of electric vehicles (EVs) is to be anticipated in future. The amount of EVs to be recycled will rise correspondingly after a delay. This includes the recyclable power electronics modules which are incorporated in every EV as an important component for energy management. Current recycling methods using car shredders and subsequent post shredder technologies show high recycling rates for the bulk metals but are still associated with high losses of precious and strategic metals such as gold, silver, platinum, palladium and tantalum. For this reason, the project 'Electric vehicle recycling 2020 - key component power electronics' developed an optimised recycling route for recycling power electronics modules from EVs which is also practicable in series production and can be implemented using standardised technology. This 'WEEE recycling route' involves the disassembly of the power electronics from the vehicle and a subsequent recycling in an electronic end-of-life equipment recycling plant. The developed recycling process is economical under the current conditions and raw material prices, even though it involves considerably higher costs than recycling using the car shredder. The life cycle assessment shows basically good results, both for the traditional car shredder route and the developed WEEE recycling route: the latter provides additional benefits from some higher recovery rates and corresponding credits.

Comparison of shear bond strength of brackets recycled using micro sandblasting and industrial methods.

PubMed

Montero, Manuela M Haro; Vicente, Ascensión; Alfonso-Hernández, Noelia; Jiménez-López, Manuel; Bravo-González, Luis-Alberto

2015-05-01

To evaluate in vitro the shear bond strength of brackets recycled by sandblasting with aluminum oxide particles of different sizes or reconditioned industrially after successive rebonding. Eighty brackets were bonded and debonded sequentially three times. After the first debonding, brackets were divided into four groups: (group 1) sandblasting with aluminum oxide particles of 25 μ, (group 2) 50 μ, and (group 3) 110 μ, and (group 4) industrial recycling. Bond strength and adhesive material remaining on debonded bracket bases were evaluated for each successive debond. No significant differences were detected between the four groups following the first recycle (P > .05). After the second recycle, bond strength was significantly greater for the industrially recycled group than the other groups (P < .016). When shear bond strength was compared within each recycling method, the bond strength of sandblasted brackets decreased with the increase of particle size and with each recycle; for the industrially recycled group, no significant differences were detected between the three sequences (P > .016). In the evaluation of bond material remnant, the industrially recycled group left significantly less bond material after successive recycling than the other groups did (P < .016). Within each recycling method, the adhesive remnant decreased significantly after successive debond (P < .016). Industrial recycling obtained better results than sandblasting after three successive debondings. The brackets' shear bond strength decreased as the size of the aluminum oxide particle used for sandblasting increased and as recycling was repeated.

Comparisons of four categories of waste recycling in China's paper industry based on physical input-output life-cycle assessment model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liang Sai; Zhang, Tianzhu, E-mail: zhangtz@mail.tsinghua.edu.cn; Xu Yijian

Highlights: Black-Right-Pointing-Pointer Using crop straws and wood wastes for paper production should be promoted. Black-Right-Pointing-Pointer Bagasse and textile waste recycling should be properly limited. Black-Right-Pointing-Pointer Imports of scrap paper should be encouraged. Black-Right-Pointing-Pointer Sensitivity analysis, uncertainties and policy implications are discussed. - Abstract: Waste recycling for paper production is an important component of waste management. This study constructs a physical input-output life-cycle assessment (PIO-LCA) model. The PIO-LCA model is used to investigate environmental impacts of four categories of waste recycling in China's paper industry: crop straws, bagasse, textile wastes and scrap paper. Crop straw recycling and wood utilization for papermore » production have small total intensity of environmental impacts. Moreover, environmental impacts reduction of crop straw recycling and wood utilization benefits the most from technology development. Thus, using crop straws and wood (including wood wastes) for paper production should be promoted. Technology development has small effects on environmental impacts reduction of bagasse recycling, textile waste recycling and scrap paper recycling. In addition, bagasse recycling and textile waste recycling have big total intensity of environmental impacts. Thus, the development of bagasse recycling and textile waste recycling should be properly limited. Other pathways for reusing bagasse and textile wastes should be explored and evaluated. Moreover, imports of scrap paper should be encouraged to reduce large indirect impacts of scrap paper recycling on domestic environment.« less

Contribution of cooperative sector recycling to greenhouse gas emissions reduction: A case study of Ribeirão Pires, Brazil

DOE Office of Scientific and Technical Information (OSTI.GOV)

King, Megan F., E-mail: mfking@uvic.ca; Gutberlet, Jutta, E-mail: gutber@uvic.ca

Highlights: • Cooperative recycling achieves environmental, economic and social objectives. • We calculate GHG emissions reduction for a recycling cooperative in São Paulo, Brazil. • The cooperative merits consideration as a Clean Development Mechanism (CDM) project. • A CDM project would enhance the achievements of the recycling cooperative. • National and local waste management policies support the recycling cooperative. - Abstract: Solid waste, including municipal waste and its management, is a major challenge for most cities and among the key contributors to climate change. Greenhouse gas emissions can be reduced through recovery and recycling of resources from the municipal solidmore » waste stream. In São Paulo, Brazil, recycling cooperatives play a crucial role in providing recycling services including collection, separation, cleaning, stocking, and sale of recyclable resources. The present research attempts to measure the greenhouse gas emission reductions achieved by the recycling cooperative Cooperpires, as well as highlight its socioeconomic benefits. Methods include participant observation, structured interviews, questionnaire application, and greenhouse gas accounting of recycling using a Clean Development Mechanism methodology. The results show that recycling cooperatives can achieve important energy savings and reductions in greenhouse gas emissions, and suggest there is an opportunity for Cooperpires and other similar recycling groups to participate in the carbon credit market. Based on these findings, the authors created a simple greenhouse gas accounting calculator for recyclers to estimate their emissions reductions.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jaech, J.L.

The use of a pooling technique in leak testing Plutonium Recycle Test Reactor fuel elements to reduce the number of tests is discussed. Since the proportion of defectives in this case is small, application of the method would suggest that the group size be large. It was suggested that additional savings might be introduced by subgrouping the originally grouped items in the event of a positive result, rather than testing them individually. An investigation was made to determine optimum subgrouping sizes. (M.C.G.)

Guide to conducting state recycling economic development finance workshops

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1996-12-31

The objective of this project was to demonstrate a two-pronged program for educating economic development and recycling officials about recycling business development opportunities. The project consisted of conducting a stat recycling finance workshop in each of three Northeastern states, as well as recycling economic development finance training program for the region`s economic development and recycling officials. The goal of the project is to facilitate the expansion of recycling businesses in the Northeast. The guide details seven steps to conducting a recycling economic development finance workshop: (1) establish a workshop planning committee, (2) select the target audience, (3) develop the workshopmore » message, (4) identify the message deliverer, (5) choose workshop topics and structure the workshop, (6) attract the audience, and (7) Conduct follow-up. In the process of planning and conducting the three state workshops for this project, NERC learned several important lessons: (1) Conduct workshops that are specific to the recycling and economic development programs in the state. (2) Include recycling business case studies on the workshop agenda. (3) Enhance the workshop with recycling economic development finance training. Develop a comprehensive marketing strategy.« less

An exploratory study of lead recovery in lead-acid battery lifecycle in US market: an evidence-based approach.

PubMed

Genaidy, A M; Sequeira, R; Tolaymat, T; Kohler, J; Rinder, M

2008-12-15

This research examines lead recovery and recycling in lead-acid batteries (LAB) which account for 88% of US lead consumption. We explore strategies to maximize lead recovery and recycling in the LAB lifecycle. Currently, there is limited information on recycling rates for LAB in the published literature and is derived from a single source. Therefore, its recycling efforts in the US has been unclear so as to determine the maximum opportunities for metal recovery and recycling in the face of significant demands for LAB particularly in the auto industry. The research utilizes an evidence-based approach to: (1) determine recycling rates for lead recovery in the LAB product lifecycle for the US market; and (2) quantify and identify opportunities where lead recovery and recycling can be improved. A comprehensive electronic search of the published literature was conducted to gather information on different LAB recycling models and actual data used to calculate recycling rates based on product lifecycle for the US market to identify strategies for increasing lead recovery and recycling. The electronic search yielded five models for calculating LAB recycling rates. The description of evidence was documented for each model. Furthermore, an integrated model was developed to identify and quantify the maximum opportunities for lead recovery and recycling. Results showed that recycling rates declined during the period spanning from 1999 to 2006. Opportunities were identified for recovery and recycling of lead in the LAB product lifecycle. One can deduce the following from the analyses undertaken in this report: (1) lead recovery and recycling has been stable between 1999 and 2006; (2) lead consumption has increased at an annual rate of 2.25%, thus, the values derived in this study for opportunities dealing with lead recovery and recycling underestimate the amount of lead in scrap and waste generated; and (3) the opportunities for maximizing lead recovery and recycling are centered on spent batteries left with consumers, mishandled LAB sent to auto wreckers, slag resulting from recycling technology process inefficiencies, and lead lost in municipal waste.

16 CFR 260.12 - Recyclable claims.

Code of Federal Regulations, 2013 CFR

2013-01-01

... established recycling program for reuse or use in manufacturing or assembling another item. (b) Marketers... the availability of recycling programs and collection sites to consumers. (1) When recycling..., means at least 60 percent. (2) When recycling facilities are available to less than a substantial...

16 CFR 260.12 - Recyclable claims.

Code of Federal Regulations, 2014 CFR

2014-01-01

... established recycling program for reuse or use in manufacturing or assembling another item. (b) Marketers... the availability of recycling programs and collection sites to consumers. (1) When recycling..., means at least 60 percent. (2) When recycling facilities are available to less than a substantial...

Testing and evaluation of recovered traction sanding material.

DOT National Transportation Integrated Search

2013-04-01

The Montana Department of Transportation (MDT) is searching for a solution to the accumulation of traction sand that is applied to Montana highways every winter. An analysis of reuse and recycle options for salvaged traction sand was conducted using ...

Performance of high RAP pavement sections in NH.

DOT National Transportation Integrated Search

2015-06-01

This report summarizes the University of New Hampshire (UNH) results of test pavements used to : determine the effect of using higher amounts of Recycled Asphalt Pavement (RAP) in Hot Mix Asphalt : (HMA). : The New Hampshire Department of Transportat...

Evaluation of the engineering characteristics of RAP/Aggregate blends.

DOT National Transportation Integrated Search

2005-07-01

"This report describes results from a research program that was structured to evaluate the : suitability of using reclaimed and recycled asphalt pavement (RAP) as an additive to crushed : angular aggregate or pit run granular soils. Research and test...

Glasphalt test sections in Virginia.

DOT National Transportation Integrated Search

1997-01-01

There is an effort to utilize waste materials in construction processes to diminish the amount placed in landfills. Mixed-color glass, which is not recyclable in the glass industry, has been used in asphalt, but there have been reservations about the...

Antimony recycling in the United States in 2000

USGS Publications Warehouse

Carlin, James F.

2006-01-01

The importance of recycling has become more obvious as concerns about the environment and import dependence have grown in recent years. When materials are recycled, fewer natural resources are consumed, and less waste products go to landfills or pollute the water and air. This study, one of a series of reports on metals recycling in 2000, discusses the flow of antimony from mining through its uses and disposal with emphasis on recycling. In 2000, the recycling efficiency for antimony was estimated to be 89 percent, and the recycling rate was about 20 percent.

Magnesium recycling in the United States in 1998

USGS Publications Warehouse

Kramer, Deborah A.

2001-01-01

As concern for the environment has grown in recent years, the importance of recycling has become more evident. The more materials that are recycled, the fewer natural resources will be consumed and the fewer waste products will end up in landfills, in the water, and in the air. As one of a series of reports on metals recycling, this report discusses the 1998 flow of magnesium from extraction through its uses with particular emphasis on recycling. In 1998, the recycling rate for magnesium was estimated to be 33 percent?almost 60 percent of the magnesium that was recycled came from new scrap, primarily waste from diecasting operations. The principal source of old scrap was recycled aluminum beverage cans.

"This is public health: recycling counts!" Description of a pilot health communications campaign.

PubMed

L Chase, Nancy; Dominick, Gregory M; Trepal, Amy; Bailey, Leanne S; Friedman, Daniela B

2009-12-01

This paper describes the development, implementation, and evaluation of a pilot recycling campaign. The goal of the campaign was to increase people's awareness and knowledge about recycling and the link between a healthy environment and the public's health. A total of 258 individuals attended campaign week events and completed an initial survey. Results identified inconvenience of recycling facility locations as a key barrier to recycling. Post-campaign survey results revealed increased recycling of paper, plastic, glass, and cans (p < 0.05). The majority of participants "agreed" or "strongly agreed" that as a result of campaign messages they had greater awareness about recycling (88.4%) and their recycling efforts increased (61.6%).

You're a "What"? Recycling Coordinator

ERIC Educational Resources Information Center

Torpey, Elka Maria

2011-01-01

Recycling coordinators supervise curbside and dropoff recycling programs for municipal governments or private firms. Today, recycling is mandatory in many communities. And advancements in collection and processing methods have helped to increase the quantity of materials for which the recycling coordinator is responsible. In some communities,…

Resource Efficient Metal and Material Recycling

NASA Astrophysics Data System (ADS)

Reuter, Markus A.; van Schaik, Antoinette

Metals enable sustainability through their use and their recyclability. However, various factors can affect the Resource Efficiency of Metal Processing and Recycling. Some typical factors that enable Resource Efficiency include and arranged under the drivers of sustainability: Environment (Maximize Resource Efficiency — Energy, Recyclates, Materials, Water, Sludges, Emissions, Land); Economic Feasibility (BAT & Recycling Systems Simulation / Digitalization, Product vis-à-vis Material Centric Recycling); and Social — Licence to Operate (Legislation, consumer, policy, theft, manual labour.). In order to realize this primary production has to be linked systemically with typical actors in the recycling chain such as Original Equipment Manufacturers (OEMs), Recyclers & Collection, Physical separation specialists as well as process metallurgical operations that produce high value metals, compounds and products that recycle back to products. This is best done with deep knowledge of multi-physics, technology, product & system design, process control, market, life cycle management, policy, to name a few. The combination of these will be discussed as Design for Sustainability (DfS) and Design for Recycling (DfR) applications.

Response to waste electrical and electronic equipments in China: legislation, recycling system, and advanced integrated process.

PubMed

Zhou, Lei; Xu, Zhenming

2012-05-01

Over the past 30 years, China has been suffering from negative environmental impacts from distempered waste electrical and electronic equipments (WEEE) recycling activities. For the purpose of environmental protection and resource reusing, China made a great effort to improve WEEE recycling. This article reviews progresses of three major fields in the development of China's WEEE recycling industry: legal system, formal recycling system, and advanced integrated process. Related laws concerning electronic waste (e-waste) management and renewable resource recycling are analyzed from aspects of improvements and loopholes. The outcomes and challenges for existing formal recycling systems are also discussed. The advantage and deficiency related to advanced integrated recycling processes for typical e-wastes are evaluated respectively. Finally, in order to achieve high disposal rates of WEEE, high-quantify separation of different materials in WEEE and high added value final products produced by separated materials from WEEE, an idea of integrated WEEE recycling system is proposed to point future development of WEEE recycling industry. © 2012 American Chemical Society

Solid-shape energy fuels from recyclable municipal solid waste and plastics

NASA Astrophysics Data System (ADS)

Gug, Jeongin

Diversion of waste streams, such as plastics, wood and paper, from municipal landfills and extraction of useful materials from landfills is an area of increasing interest across the country, especially in densely populated areas. One promising technology for recycling MSW (municipal solid waste) is to burn the high energy content components in standard coal boilers. This research seeks to reform wastes into briquette that are compatible with typical coal combustion processes. In order to comply with the standards of coal-fired power plants, the feedstock must be mechanically robust, moisture resistance, and retain high fuel value. Household waste with high paper and fibers content was used as the base material for this study. It was combined with recyclable plastics such as PE, PP, PET and PS for enhanced binding and energy efficiency. Fuel pellets were processed using a compression molding technique. The resulting moisture absorption, proximate analysis from burning, and mechanical properties were investigated after sample production and then compared with reference data for commercial coals and biomass briquettes. The effects of moisture content, compression pressure and processing temperature were studied to identify the optimal processing conditions with water uptake tests for the durability of samples under humid conditions and burning tests to examine the composition of samples. Lastly, mechanical testing revealed the structural stability of solid fuels. The properties of fuel briquettes produced from waste and recycled plastics improved with higher processing temperature but without charring the material. Optimization of moisture content and removal of air bubbles increased the density, stability and mechanical strength. The sample composition was found to be more similar to biomass fuels than coals because the majority of the starting material was paper-based solid waste. According to the proximate analysis results, the waste fuels can be expected to have low temperature ignition, less char formation and reduced CO2 emission with the high heating energy value similar to coal. It is concluded that solid fuels from paper based waste and plastics can be a good energy resource as an alternative and sustainable fuel, which may help to alleviate the environmental problems related to landfill space at the same time.

40 CFR Appendix C to Subpart B of... - SAE J2788 Standard for Recovery/Recycle and Recovery/Recycle/Recharging Equipment for HFC-134a...

Code of Federal Regulations, 2012 CFR

2012-07-01

... requirements for the recovery/recycling of HFC-134a that has been directly removed from, and is intended for reuse in, mobile air-conditioning systems and recovery/recycling and system recharging of recycled... requirements for recovery and recycling of HFC-134a that has been directly removed from, and is intended for...

40 CFR Appendix C to Subpart B of... - SAE J2788 Standard for Recovery/Recycle and Recovery/Recycle/Recharging Equipment for HFC-134a...

Code of Federal Regulations, 2013 CFR

2013-07-01

... requirements for the recovery/recycling of HFC-134a that has been directly removed from, and is intended for reuse in, mobile air-conditioning systems and recovery/recycling and system recharging of recycled... requirements for recovery and recycling of HFC-134a that has been directly removed from, and is intended for...

40 CFR Appendix C to Subpart B of... - SAE J2788 Standard for Recovery/Recycle and Recovery/Recycle/Recharging Equipment for HFC-134a...

Code of Federal Regulations, 2011 CFR

2011-07-01

... requirements for the recovery/recycling of HFC-134a that has been directly removed from, and is intended for reuse in, mobile air-conditioning systems and recovery/recycling and system recharging of recycled... requirements for recovery and recycling of HFC-134a that has been directly removed from, and is intended for...

Management status of end-of-life vehicles and development strategies of used automotive electronic control components recycling industry in China.

PubMed

Wang, Junjun; Chen, Ming

2012-11-01

Recycling companies play a leading role in the system of end-of-life vehicles (ELVs) in China. Automotive manufacturers in China are rarely involved in recycling ELVs, and they seldom provide dismantling information for recycling companies. In addition, no professional shredding plant is available. The used automotive electronic control components recycling industry in China has yet to take shape because of the lack of supporting technology and profitable models. Given the rapid growth of the vehicle population and electronic control units in automotives in China, the used automotive electronic control components recycling industry requires immediate development. This paper analyses the current recycling system of ELVs in China and introduces the automotive product recycling technology roadmap as well as the recycling industry development goals. The strengths, weaknesses, opportunities and challenges of the current used automotive electronic control components recycling industry in China are analysed comprehensively based on the 'strengths, weaknesses, opportunities and threats' (SWOT) method. The results of the analysis indicate that this recycling industry responds well to all the factors and has good opportunities for development. Based on the analysis, new development strategies for the used automotive electronic control components recycling industry in accordance with the actual conditions of China are presented.

Mechanical and chemical recycling of solid plastic waste.

PubMed

Ragaert, Kim; Delva, Laurens; Van Geem, Kevin

2017-11-01

This review presents a comprehensive description of the current pathways for recycling of polymers, via both mechanical and chemical recycling. The principles of these recycling pathways are framed against current-day industrial reality, by discussing predominant industrial technologies, design strategies and recycling examples of specific waste streams. Starting with an overview on types of solid plastic waste (SPW) and their origins, the manuscript continues with a discussion on the different valorisation options for SPW. The section on mechanical recycling contains an overview of current sorting technologies, specific challenges for mechanical recycling such as thermo-mechanical or lifetime degradation and the immiscibility of polymer blends. It also includes some industrial examples such as polyethylene terephthalate (PET) recycling, and SPW from post-consumer packaging, end-of-life vehicles or electr(on)ic devices. A separate section is dedicated to the relationship between design and recycling, emphasizing the role of concepts such as Design from Recycling. The section on chemical recycling collects a state-of-the-art on techniques such as chemolysis, pyrolysis, fluid catalytic cracking, hydrogen techniques and gasification. Additionally, this review discusses the main challenges (and some potential remedies) to these recycling strategies and ground them in the relevant polymer science, thus providing an academic angle as well as an applied one. Copyright © 2017 Elsevier Ltd. All rights reserved.

Quantitative Analysis of Endocytic Recycling of Membrane Proteins by Monoclonal Antibody-Based Recycling Assays.

PubMed

Blagojević Zagorac, Gordana; Mahmutefendić, Hana; Maćešić, Senka; Karleuša, Ljerka; Lučin, Pero

2017-03-01

In this report, we present an analysis of several recycling protocols based on labeling of membrane proteins with specific monoclonal antibodies (mAbs). We analyzed recycling of membrane proteins that are internalized by clathrin-dependent endocytosis, represented by the transferrin receptor, and by clathrin-independent endocytosis, represented by the Major Histocompatibility Class I molecules. Cell surface membrane proteins were labeled with mAbs and recycling of mAb:protein complexes was determined by several approaches. Our study demonstrates that direct and indirect detection of recycled mAb:protein complexes at the cell surface underestimate the recycling pool, especially for clathrin-dependent membrane proteins that are rapidly reinternalized after recycling. Recycling protocols based on the capture of recycled mAb:protein complexes require the use of the Alexa Fluor 488 conjugated secondary antibodies or FITC-conjugated secondary antibodies in combination with inhibitors of endosomal acidification and degradation. Finally, protocols based on the capture of recycled proteins that are labeled with Alexa Fluor 488 conjugated primary antibodies and quenching of fluorescence by the anti-Alexa Fluor 488 displayed the same quantitative assessment of recycling as the antibody-capture protocols. J. Cell. Physiol. 232: 463-476, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Are scarce metals in cars functionally recycled?

PubMed

Andersson, Magnus; Ljunggren Söderman, Maria; Sandén, Björn A

2017-02-01

Improved recycling of end-of-life vehicles (ELVs) may serve as an important strategy to address resource security risks related to increased global demand for scarce metals. However, in-depth knowledge of the magnitude and fate of such metals entering ELV recycling is lacking. This paper quantifies input of 25 scarce metals to Swedish ELV recycling, and estimates the extent to which they are recycled to material streams where their metal properties are utilised, i.e. are functionally recycled. Methodologically, scarce metals are mapped to main types of applications within newly produced Swedish car models and subsequently, material flow analysis of ELV waste streams is used as basis for identifying pathways of these applications and assessing whether contained metals are functionally recycled. Results indicate that, of the scarce metals, only platinum may be functionally recycled in its main application. Cobalt, gold, manganese, molybdenum, palladium, rhodium and silver may be functionally recycled depending on application and pathways taken. For remaining 17 metals, functional recycling is absent. Consequently, despite high overall ELV recycling rates of materials in general, there is considerable risk of losing ELV scarce metals to carrier metals, construction materials, backfilling materials and landfills. Given differences in the application of metals and identified pathways, prospects for increasing functional recycling are discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Three Rs: Reduce, Reuse, Recycle.

ERIC Educational Resources Information Center

Science Activities, 1991

1991-01-01

A student hand-out for a recycling unit defines the terms reduce, recycle, and reuse as they relate to solid waste management. Presents the characteristics of recyclable items such as yard wastes, metals, glass, and paper. Lists organizations through which more information about recycling can be obtained. (MCO)

Milestone Report - M4FT-14OR0312022 - Co-absorption studies - Design system complete/test plan complete

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bruffey, Stephanie H.; Spencer, Barry B.; Jubin, Robert Thomas

2013-12-01

The objective of this test plan is to describe research that will determine the effectiveness of silver mordenite and molecular sieve beds to remove iodine and water (tritium) from off-gas streams arising from used nuclear fuel recycling processes, and to demonstrate that the iodine and water can be recovered separately from one another.

Fate and Transport of Bacteriophage (MS2 and PRD1) During Field-Scale Infiltration at a Research Site in Los Angeles County, CA

NASA Astrophysics Data System (ADS)

Anders, R.; Chrysikopoulos, C. V.

2003-12-01

As the use of tertiary-treated municipal wastewater (recycled water) for replenishment purposes continues to increase, provisions are being established to protect ground-water resources by ensuring that adequate soil-retention time and distance requirements are met for pathogen removal. However, many of the factors controlling virus fate and transport (e.g. hydraulic conditions, ground-water chemistry, and sediment mineralogy) are interrelated and poorly understood. Therefore, conducting field-scale experiments using surrogates for human enteric viruses at an actual recharge basin that uses recycled water may represent the best approach for establishing adequate setback requirements. Three field-scale infiltration experiments were conducted at such a basin using bacterial viruses (bacteriophage) MS2 and PRD1 as surrogates for human viruses, bromide as a conservative tracer, and recycled water. The specific research site consists of a test basin constructed adjacent to a large recharge facility (spreading grounds) located in the Montebello Forebay of Los Angeles County, California. The soil beneath the test basin is predominantly medium to coarse, moderately sorted, grayish-brown sand. The first experiment was conducted over a 2-day period to determine the feasibility of conducting field-scale infiltration experiments using recycled water seeded with high concentrations of bacteriophage and bromide as tracers. Based on the results of the first experiment, a second experiment was completed when similar hydraulic conditions existed at the test basin. The third infiltration experiment was conducted to confirm the results obtained from the second experiment. Data were obtained for samples collected during the second and third field-scale infiltration experiments from the test basin itself and from depths of 0.3, 0.6, 1.0, 1.5, 3.0, and 7.6 m below the bottom of the test basin. These field-scale tracer experiments indicate bacteriophage are attenuated by removal and (or) inactivation during subsurface transport. To simulate the transport and fate of viruses during infiltration, a nonlinear least-squares regression program was used to fit a one-dimensional virus transport model to the experimental data. The model simulates virus transport in homogeneous, saturated porous media with first-order adsorption (or filtration) and inactivation. Furthermore, the model obtains a semi-analytical solution for the special case of a broad pulse and time-dependent source concentration using the principle of superposition. The fitted parameters include the clogging and declogging rate constants and the inactivation constants of suspended and adsorbed viruses. Preliminary results show a reasonable match of the first arrival of bacteriophage and bromide.

Construction technique of disposable bin from sludge cake and its environmental risk.

PubMed

Kongmuang, Udomsak; Kiykaew, Duangta; Morioka, Ikuharu

2015-01-01

Now, a lot of researchers have tried to make recycled rigid materials from the sludge cake produced in paper mill industries for the purpose of decreasing its volume. In this study, the researchers tried to make economically a disposable bin and to examine whether it is toxic or not to the outside environment. To make a disposable bin, the researchers used the sludge cake, a plastic basket, as a fixed mold, white cloth or newspaper, as a removable supporter for wrapping around the mold, and latex or plaster, as a binder. The strength of the samples was measured by tensile-stress testing. The water absorption was evaluated by Cobb test. As toxicological tests, leaching test and seed germination test were selected. It was possible to form the disposal bin from the cleaned sludge cake. They seemed safe to carry garbage in the industry judging from the results of tensile-stress testing. Some of them showed less water absorptiveness (higher water resistance) in the results of Cobb test. The results of leaching test showed small values of three heavy metals, lead, nickel and copper, in the leachate. The seed germination test suggested no adverse effects of the bins in the clay and sand on the tomato growth. The results of these tests suggest that the bins have good strength, sufficient water resistance and no toxicological effect on the environment. This new recycled bin has the possibility to solve the environmental and health problems at disposing the sludge cake.

Green Science: Revisiting Recycling

ERIC Educational Resources Information Center

Palliser, Janna

2011-01-01

Recycling has been around for a long time--people have reused materials and refashioned them into needed items for thousands of years. More recently, war efforts encouraged conservation and reuse of materials, and in the 1970s recycling got its official start when recycling centers were created. Now, curbside recycling programs and recycling…

78 FR 69531 - America Recycles Day, 2013

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-19

.... Recycling not only reduces pollution, but also saves energy, preserves valuable raw materials, and reduces... recycling a part of our daily lives. We should reuse or donate when possible, and recycle or compost as much as we are able. Students can get involved by championing waste-free lunches, recycling programs, and...

Quantify the energy and environmental effects of using recycled asphalt and recycled concrete for pavement construction phase I : final report.

DOT National Transportation Integrated Search

2009-08-01

The objective of this study is to quantify the energy and environment impacts from using recycled materials : for highway construction. Specifically, when recycled asphalt pavement is re-used for producing hot mix : asphalt or when recycled concrete ...

Recycling steel. Conducting a waste audit.

PubMed

Crawford, G

1996-01-01

This is the second in a series of three articles regarding steel can recycling from foodservice operations of healthcare facilities. This article highlights the basic methods of recycling steel cans, and includes information on conducting a waste audit and negotiating with a hauler regarding the benefits of recycling. The previous article discussed how steel is recycled across the country. The next article will convey a case history of actual foodservice recycling practice from a healthcare facility.

Magnesium recycling in the United States in 1998

USGS Publications Warehouse

Kramer, Deborah A.

2002-01-01

As concern for the environment has grown in recent years, the importance of recycling has become more evident. The more materials that are recycled, the fewer natural resources will be consumed and the fewer waste products will end up in landfills, the water, and the air. As one of a series of reports on metals recycling, this report discusses the 1998 flow of magnesium in the United States from extraction through its uses with particular emphasis on recycling. In 1998, the recycling efficiency for magnesium was estimated to be 33 percent--almost 60 percent of the magnesium that was recycled came from new scrap, primarily waste from die-casting operations. The principal source of old scrap was recycled aluminum beverage cans.

Sustaining the environment through recycling: an empirical study.

PubMed

Ramayah, T; Lee, Jason Wai Chow; Lim, Shuwen

2012-07-15

This paper examines the determinants of recycling behaviour among 200 university students from the perspective of the theory of planned behaviour (TPB). Data was analysed using Structural Equation Modelling technique. Findings indicate that environmental awareness was significantly related to attitude towards recycling, whilst attitude and social norms had significant impact on recycling behaviour. However, convenience and cost of recycling were not significant reasons for recycling. The study has enhanced the understanding of the determinants of recycling behaviour and has implications for schools and governmental agencies in educating and encouraging positive recycling behaviour. It also confirms the appropriateness of the TPB in examining studies of this nature. Further suggestions for future research are offered. Copyright © 2012 Elsevier Ltd. All rights reserved.

“This Is Public Health: Recycling Counts!” Description of a Pilot Health Communications Campaign

PubMed Central

L.Chase, Nancy; Dominick, Gregory M.; Trepal, Amy; Bailey, Leanne S.; Friedman, Daniela B.

2009-01-01

This paper describes the development, implementation, and evaluation of a pilot recycling campaign. The goal of the campaign was to increase people’s awareness and knowledge about recycling and the link between a healthy environment and the public’s health. A total of 258 individuals attended campaign week events and completed an initial survey. Results identified inconvenience of recycling facility locations as a key barrier to recycling. Post-campaign survey results revealed increased recycling of paper, plastic, glass, and cans (p < 0.05). The majority of participants “agreed” or “strongly agreed” that as a result of campaign messages they had greater awareness about recycling (88.4%) and their recycling efforts increased (61.6%). PMID:20049239

Recycling carbon fibre reinforced polymers for structural applications: technology review and market outlook.

PubMed

Pimenta, Soraia; Pinho, Silvestre T

2011-02-01

Both environmental and economic factors have driven the development of recycling routes for the increasing amount of carbon fibre reinforced polymer (CFRP) waste generated. This paper presents a review of the current status and outlook of CFRP recycling operations, focusing on state-of-the-art fibre reclamation and re-manufacturing processes, and on the commercialisation and potential applications of recycled products. It is shown that several recycling and re-manufacturing processes are reaching a mature stage, with implementations at commercial scales in operation, production of recycled CFRPs having competitive structural performances, and demonstrator components having been manufactured. The major challenges for the sound establishment of a CFRP recycling industry and the development of markets for the recyclates are summarised; the potential for introducing recycled CFRPs in structural components is discussed, and likely promising applications are investigated. Copyright © 2010 Elsevier Ltd. All rights reserved.

Aluminum recycling in the United States in 2000

USGS Publications Warehouse

Plunkert, Patricia A.

2006-01-01

As one of a series of reports on metals recycling, this report discusses the flow of aluminum from production through its uses with particular emphasis on the recycling of industrial scrap (new scrap) and used products (old scrap) in 2000. This materials flow study includes a description of aluminum supply and demand factors for the United States to illustrate the extent of aluminum recycling and to identify recycling trends. Understanding the system of materials flow from source to ultimate disposition can assist in improving the management of natural resources in a manner that is compatible with sound environmental practices. In 2000, the old scrap recycling efficiency for aluminum was estimated to be 42 percent. Almost 60 percent of the aluminum that was recycled in 2000 came from new scrap, and the recycling rate was estimated to be 36 percent. The principal source of old scrap was recycled aluminum beverage cans.

Manganese recycling in the United States in 1998

USGS Publications Warehouse

Jones, Thomas S.

2001-01-01

This report describes the flow and processing of manganese within the U.S. economy in 1998 with emphasis on the extent to which manganese is recycled. Manganese was used mostly as an alloying agent in alloys in which it was a minor component. Manganese was recycled mostly within scrap of iron and steel. A small amount was recycled within aluminum used beverage cans. Very little manganese was recycled from materials being recovered specifically for their manganese content. For the United States in 1998, 218,000 metric tons of manganese was estimated to have been recycled from old scrap, of which 96% was from iron and steel scrap. Efficiency of recycling was estimated as 53% and recycling rate as 37%. Metallurgical loss of manganese was estimated to be about 1.7 times that recycled. This loss was mostly into slags from iron and steel production, from which recovery of manganese has yet to be shown economically feasible.

The Recycling Endosome of Madin-Darby Canine Kidney Cells Is a Mildly Acidic Compartment Rich in Raft Components

PubMed Central

Gagescu, Raluca; Demaurex, Nicolas; Parton, Robert G.; Hunziker, Walter; Huber, Lukas A.; Gruenberg, Jean

2000-01-01

We present a biochemical and morphological characterization of recycling endosomes containing the transferrin receptor in the epithelial Madin-Darby canine kidney cell line. We find that recycling endosomes are enriched in molecules known to regulate transferrin recycling but lack proteins involved in early endosome membrane dynamics, indicating that recycling endosomes are distinct from conventional early endosomes. We also find that recycling endosomes are less acidic than early endosomes because they lack a functional vacuolar ATPase. Furthermore, we show that recycling endosomes can be reached by apically internalized tracers, confirming that the apical endocytic pathway intersects the transferrin pathway. Strikingly, recycling endosomes are enriched in the raft lipids sphingomyelin and cholesterol as well as in the raft-associated proteins caveolin-1 and flotillin-1. These observations may suggest that a lipid-based sorting mechanism operates along the Madin-Darby canine kidney recycling pathway, contributing to the maintenance of cell polarity. Altogether, our data indicate that recycling endosomes and early endosomes differ functionally and biochemically and thus that different molecular mechanisms regulate protein sorting and membrane traffic at each step of the receptor recycling pathway. PMID:10930469

Recycling production designs: the value of coordination and flexibility in aluminum recycling operations

NASA Astrophysics Data System (ADS)

Brommer, Tracey H.

The growing motivation for aluminum recycling has prompted interest in recycling alternative and more challenging secondary materials. The nature of these alternative secondary materials necessitates the development of an intermediate recycling facility that can reprocess the secondary materials into a liquid product Two downstream aluminum remelters will incorporate the liquid products into their aluminum alloy production schedules. Energy and environmental benefits result from delivering the products as liquid but coordination challenges persist because of the energy cost to maintain the liquid. Further coordination challenges result from the necessity to establish a long term recycling production plan in the presence of long term downstream aluminum remelter production uncertainty and inherent variation in the daily order schedule of the downstream aluminum remelters. In this context a fundamental question arises, considering the metallurgical complexities of dross reprocessing, what is the value of operating a coordinated set of by-product reprocessing plants and remelting cast houses? A methodology is presented to calculate the optimal recycling center production parameters including 1) the number of recycled products, 2) the volume of recycled products, 3) allocation of recycled materials across recycled products, 4) allocation of recycled products across finished alloys, 4) the level of flexibility for the recycling center to operate. The methods implemented include, 1) an optimization model to describe the long term operations of the recycling center, 2) an uncertainty simulation tool, 3) a simulation optimization method, 4) a dynamic simulation tool with four embedded daily production optimization models of varying degrees of flexibility. This methodology is used to quantify the performance of several recycling center production designs of varying levels of coordination and flexibility. This analysis allowed the identification of the optimal recycling center production design based on maximizing liquid recycled product incorporation and minimizing cast sows. The long term production optimization model was used to evaluate the theoretical viability of the proposed two stage scrap and aluminum dross reprocessing operation including the impact of reducing coordination on model performance. Reducing the coordination between the recycling center and downstream remelters by reducing the number of recycled products from ten to five resulted in only 1.3% less secondary materials incorporated into downstream production. The dynamic simulation tool was used to evaluate the performance of the calculated recycling center production plan when resolved on a daily timeframe for varying levels of operational flexibility. The dynamic simulation revealed the optimal performance corresponded to the fixed recipe with flexible production daily optimization model formulation. Calculating recycled product characteristics using the proposed simulation optimization method increased profitability in cases of uncertain downstream remelter production and expensive aluminum dross and post-consumed secondary materials. (Copies available exclusively from MIT Libraries, libraries.mit.edu/docs - docs@mit.edu)

HTGR fuels and core development program. Quarterly progress report for the period ending August 31, 1975

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

1975-09-30

Studies of reactions between core materials and coolant impurities, basic fission product transport mechanisms, core graphite development and testing, the development and testing of recyclable fuel systems, and physics and fuel management studies are described. Materials studies include irradiation capsule tests of both fuel and graphite. Experimental procedures and results are discussed and, where appropriate, the data are presented in tables, graphs, and photographs. (auth)

DOE Office of Scientific and Technical Information (OSTI.GOV)

SAMS TL; GUILLOT S

Scoping laboratory scale tests were performed at the Chemical Engineering Department of the Georgia Institute of Technology (Georgia Tech), and the Hanford 222-S Laboratory, involving double-shell tank (DST) and single-shell tank (SST) Hanford waste simulants. These tests established the viability of the Lithium Hydrotalcite precipitation process as a solution to remove aluminum and recycle sodium hydroxide from the Hanford tank waste, and set the basis of a validation test campaign to demonstrate a Technology Readiness Level of 3.

Construction and testing of crumb rubber modified hot mix asphalt pavement.

DOT National Transportation Integrated Search

1999-12-01

This research project was structured toward addressing that portion of ISTEA which directs the individual states to conduct studies on the recyclability of crumb rubber modified : (CRM) hot mix asphalt (HMA) and the technical performance of CRMHMA pa...

Fundamental evaluation of the interaction between RAS/RAP and virgin asphalt binders.

DOT National Transportation Integrated Search

2017-08-01

A comprehensive laboratory testing program was conducted in this research project to examine the blending between reclaimed asphalt pavement (RAP)/recycled asphalt shingles (RAS) and virgin asphalt binders and to evaluate the factors that may affect ...

Study of the Technical Feasibility of Increasing the Amount of Recycled Concrete Waste Used in Ready-Mix Concrete Production

PubMed Central

Ferreiro-Cabello, Javier; López-González, Luis M.

2017-01-01

The construction industry generates a considerable amount of waste. Faced with this undesirable situation, the ready-mix concrete sector, in particular, has invested energy and resources into reusing its own waste in its production process as it works towards the goal of more sustainable construction. This study examines the feasibility of incorporating two types of concrete waste, which currently end up in landfill, into the production process of ready-mix concrete: the waste generated during the initial production stage (ready-mix concrete waste), and waste created when demolition waste is treated to obtain artificial aggregate. The first phase of the study’s methodology corroborates the suitability of the recycled aggregate through characterization tests. After this phase, the impact of incorporating different percentages of recycled coarse aggregate is evaluated by examining the performance of the produced concrete. The replacement rate varied between 15% and 50%. The results indicate that recycled aggregates are, indeed, suitable to be incorporated into ready-mix concrete production. The impact on the final product’s performance is different for the two cases examined herein. Incorporating aggregates from generic concrete blocks led to a 20% decrease in the produced concrete’s strength performance. On the other hand, using recycled aggregates made from the demolition waste led to a smaller decrease in the concrete’s performance: about 8%. The results indicate that with adequate management and prior treatment, the waste from these plants can be re-incorporated into their production processes. If concrete waste is re-used, concrete production, in general, becomes more sustainable for two reasons: less waste ends up as landfill and the consumption of natural aggregates is also reduced. PMID:28773183

Mass Lead Intoxication from Informal Used Lead-Acid Battery Recycling in Dakar, Senegal

PubMed Central

Haefliger, Pascal; Mathieu-Nolf, Monique; Lociciro, Stephanie; Ndiaye, Cheikh; Coly, Malang; Diouf, Amadou; Faye, Absa Lam; Sow, Aminata; Tempowski, Joanna; Pronczuk, Jenny; Junior, Antonio Pedro Filipe; Bertollini, Roberto; Neira, Maria

2009-01-01

Background and objectives Between November 2007 and March 2008, 18 children died from a rapidly progressive central nervous system disease of unexplained origin in a community involved in the recycling of used lead-acid batteries (ULAB) in the suburbs of Dakar, Senegal. We investigated the cause of these deaths. Methods Because autopsies were not possible, the investigation centered on clinical and laboratory assessments performed on 32 siblings of deceased children and 23 mothers and on 18 children and 8 adults living in the same area, complemented by environmental health investigations. Results All 81 individuals investigated were poisoned with lead, some of them severely. The blood lead level of the 50 children tested ranged from 39.8 to 613.9 μg/dL with a mean of 129.5 μg/dL. Seventeen children showed severe neurologic features of toxicity. Homes and soil in surrounding areas were heavily contaminated with lead (indoors, up to 14,000 mg/kg; outdoors, up to 302,000 mg/kg) as a result of informal ULAB recycling. Conclusions Our investigations revealed a mass lead intoxication that occurred through inhalation and ingestion of soil and dust heavily contaminated with lead as a result of informal and unsafe ULAB recycling. Circumstantial evidence suggested that most or all of the 18 deaths were due to encephalopathy resulting from severe lead intoxication. Findings also suggest that most habitants of the contaminated area, estimated at 950, are also likely to be poisoned. This highlights the severe health risks posed by informal ULAB recycling, in particular in developing countries, and emphasizes the need to strengthen national and international efforts to address this global public health problem. PMID:20019903

Mass lead intoxication from informal used lead-acid battery recycling in dakar, senegal.

PubMed

Haefliger, Pascal; Mathieu-Nolf, Monique; Lociciro, Stephanie; Ndiaye, Cheikh; Coly, Malang; Diouf, Amadou; Faye, Absa Lam; Sow, Aminata; Tempowski, Joanna; Pronczuk, Jenny; Filipe Junior, Antonio Pedro; Bertollini, Roberto; Neira, Maria

2009-10-01

Between November 2007 and March 2008, 18 children died from a rapidly progressive central nervous system disease of unexplained origin in a community involved in the recycling of used lead-acid batteries (ULAB) in the suburbs of Dakar, Senegal. We investigated the cause of these deaths. Because autopsies were not possible, the investigation centered on clinical and laboratory assessments performed on 32 siblings of deceased children and 23 mothers and on 18 children and 8 adults living in the same area, complemented by environmental health investigations. All 81 individuals investigated were poisoned with lead, some of them severely. The blood lead level of the 50 children tested ranged from 39.8 to 613.9 microg/dL with a mean of 129.5 microg/dL. Seventeen children showed severe neurologic features of toxicity. Homes and soil in surrounding areas were heavily contaminated with lead (indoors, up to 14,000 mg/kg; outdoors, up to 302,000 mg/kg) as a result of informal ULAB recycling. Our investigations revealed a mass lead intoxication that occurred through inhalation and ingestion of soil and dust heavily contaminated with lead as a result of informal and unsafe ULAB recycling. Circumstantial evidence suggested that most or all of the 18 deaths were due to encephalopathy resulting from severe lead intoxication. Findings also suggest that most habitants of the contaminated area, estimated at 950, are also likely to be poisoned. This highlights the severe health risks posed by informal ULAB recycling, in particular in developing countries, and emphasizes the need to strengthen national and international efforts to address this global public health problem.

Study of the Technical Feasibility of Increasing the Amount of Recycled Concrete Waste Used in Ready-Mix Concrete Production.

PubMed

Fraile-Garcia, Esteban; Ferreiro-Cabello, Javier; López-Ochoa, Luis M; López-González, Luis M

2017-07-18

The construction industry generates a considerable amount of waste. Faced with this undesirable situation, the ready-mix concrete sector, in particular, has invested energy and resources into reusing its own waste in its production process as it works towards the goal of more sustainable construction. This study examines the feasibility of incorporating two types of concrete waste, which currently end up in landfill, into the production process of ready-mix concrete: the waste generated during the initial production stage (ready-mix concrete waste), and waste created when demolition waste is treated to obtain artificial aggregate. The first phase of the study's methodology corroborates the suitability of the recycled aggregate through characterization tests. After this phase, the impact of incorporating different percentages of recycled coarse aggregate is evaluated by examining the performance of the produced concrete. The replacement rate varied between 15% and 50%. The results indicate that recycled aggregates are, indeed, suitable to be incorporated into ready-mix concrete production. The impact on the final product's performance is different for the two cases examined herein. Incorporating aggregates from generic concrete blocks led to a 20% decrease in the produced concrete's strength performance. On the other hand, using recycled aggregates made from the demolition waste led to a smaller decrease in the concrete's performance: about 8%. The results indicate that with adequate management and prior treatment, the waste from these plants can be re-incorporated into their production processes. If concrete waste is re-used, concrete production, in general, becomes more sustainable for two reasons: less waste ends up as landfill and the consumption of natural aggregates is also reduced.

Recycling of high purity selenium from CIGS solar cell waste materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gustafsson, Anna M.K., E-mail: anna.gustafsson@chalmers.se; Foreman, Mark R.StJ.; Ekberg, Christian

Highlights: • A new method for recycling of selenium from CIGS solar cell materials is presented. • Separation of selenium as selenium dioxide after heating in oxygen atmosphere. • Complete selenium separation after oxidation of <63 μm particles at 800 °C for 1 h. • After reduction of selenium dioxide the selenium purity was higher than 99.999 wt%. - Abstract: Copper indium gallium diselenide (CIGS) is a promising material in thin film solar cell production. To make CIGS solar cells more competitive, both economically and environmentally, in comparison to other energy sources, methods for recycling are needed. In addition tomore » the generally high price of the material, significant amounts of the metals are lost in the manufacturing process. The feasibility of recycling selenium from CIGS through oxidation at elevated temperatures was therefore examined. During oxidation gaseous selenium dioxide was formed and could be separated from the other elements, which remained in solid state. Upon cooling, the selenium dioxide sublimes and can be collected as crystals. After oxidation for 1 h at 800 °C all of the selenium was separated from the CIGS material. Two different reduction methods for reduction of the selenium dioxide to selenium were tested. In the first reduction method an organic molecule was used as the reducing agent in a Riley reaction. In the second reduction method sulphur dioxide gas was used. Both methods resulted in high purity selenium. This proves that the studied selenium separation method could be the first step in a recycling process aimed at the complete separation and recovery of high purity elements from CIGS.« less

Evaluation of concrete recycling system efficiency for ready-mix concrete plants.

PubMed

Vieira, Luiz de Brito Prado; Figueiredo, Antonio Domingues de

2016-10-01

The volume of waste generated annually in concrete plants is quite large and has important environmental and economic consequences. The use of fresh concrete recyclers is an interesting way for the reuse of aggregates and water in new concrete production. This paper presents a study carried out for over one year by one of the largest ready-mix concrete producers in Brazil. This study focused on the evaluation of two recyclers with distinct material separation systems, herein referred to as drum-type and rotary sieve-type equipment. They were evaluated through characterization and monitoring test programs to verify the behaviour of recovered materials (aggregates, water, and slurry). The applicability of the recovered materials (water and aggregates) was also evaluated in the laboratory and at an industrial scale. The results obtained with the two types of recyclers used were equivalent and showed no significant differences. The only exception was in terms of workability. The drum-type recycler generated fewer cases that required increased pumping pressure. The analysis concluded that the use of untreated slurry is unfeasible because of its intense negative effects on the strength and workability of concrete. The reclaimed water, pre-treated to ensure that its density is less than 1.03g/cm(3), can be used on an industrial scale without causing any harm to the concrete. The use of recovered aggregates consequently induces an increase in water demand and cement consumption to ensure the workability conditions of concrete that is proportional to the concrete strength level. Therefore, the viability of their use is restricted to concretes with characteristic strengths lower than 25MPa. Copyright © 2016 Elsevier Ltd. All rights reserved.

Monitoring of lead load and its effect on neonatal behavioral neurological assessment scores in Guiyu, an electronic waste recycling town in China.

PubMed

Li, Yan; Xu, Xijin; Wu, Kusheng; Chen, Gangjian; Liu, Junxiao; Chen, Songjian; Gu, Chengwu; Zhang, Bao; Zheng, Liangkai; Zheng, Minghao; Huo, Xia

2008-10-01

Guiyu is the major electronic waste (e-waste) recycling town in China. The primary purpose of this study was to measure the lead levels in neonates and examine the correlation between lead levels and neurobehavioral development. One hundred full-term neonates from Guiyu and fifty-two neonates from neighboring towns (control group) in the late summer of 2006 were selected for study. The lead levels in the umbilical cord blood (CBPb) and lead levels in meconium (MPb) of neonates were determined with atomic absorption spectrophotometry. The neonatal behavioral neurological assessment (NBNA) was conducted on all neonates. A questionnaire related to the exposure to lead of pregnant women was used as a survey of the neonates' mothers. Compared with the control group, neonates in Guiyu had significantly higher levels of lead (P < 0.01), and the mean CBPb and MPb were 113.28 microg L(-1) and 2.50 microg g(-1), respectively. The relatively high lead levels in the neonates of the Guiyu group were found to correlate with their maternal occupation in relation to e-waste recycling. Neonates with high levels of lead load have lower NBNA scores (P < 0.01). There was a statistically significant difference in NBNA scores between the Guiyu group and the control group by t test (P < 0.05). No correlation was found between CBPb and NBNA scores; however, a negative correlation was found between MPb and NBNA scores (P < 0.01). There is a correlation between relatively high lead levels in the umbilical cord blood and meconium in neonates and the local e-waste recycling activities related to lead contamination. This study suggests that environmental lead contamination due to e-waste recycling have an impact on neurobehavioral development of neonates in Guiyu.

Detection of recycled marine sediment components in crater lake fluids using 129I

NASA Astrophysics Data System (ADS)

Fehn, U.; Snyder, G. T.; Varekamp, J. C.

2002-06-01

Crater lakes provide time-integrated samples of volcanic fluids, which may carry information on source components. We tested under what circumstances 129I concentrations can be used for the detection of a signal derived from the recycling of marine sediments in subduction zone magmatism. The 129I system has been successfully used to determine origin and pathways in other volcanic fluids, but the application of this system to crater lakes is complicated by the presence of anthropogenic 129I, related to recent nuclear activities. Results are reported from four crater lakes, associated with subducting crust varying in age between 23 and 98 Ma. The 129I/I ratios determined for Copahue, Argentina, (129I/I=700×10-15) and White Island, New Zealand, (129I/I=284×10-15) demonstrate the presence of iodine in the crater lakes that was derived from recycled marine sediments. A comparison to the ages of the subducted sediments in these two cases indicates that the ratios likely reflect iodine remobilization from the entire sediment column that was undergoing subduction. While the 129I signals in Poás and Rincón de la Vieja, Costa Rica also demonstrate the presence of recycled iodine, the relatively high percentage of meteoric water in these lakes prevents a reliable determination of source ages. The observed high concentrations of iodine and 129I/I ratios substantially below current surface values strongly argue for the presence of recycled marine components in the arc magmas of all four cases. Components from subducted marine sediments can be quantified and related to specific parts of the sediment column in cases where the iodine concentration in the lake waters exceeds 5 μM.

Model-Based Diagnosis and Prognosis of a Water Recycling System

NASA Technical Reports Server (NTRS)

Roychoudhury, Indranil; Hafiychuk, Vasyl; Goebel, Kai Frank

2013-01-01

A water recycling system (WRS) deployed at NASA Ames Research Center s Sustainability Base (an energy efficient office building that integrates some novel technologies developed for space applications) will serve as a testbed for long duration testing of next generation spacecraft water recycling systems for future human spaceflight missions. This system cleans graywater (waste water collected from sinks and showers) and recycles it into clean water. Like all engineered systems, the WRS is prone to standard degradation due to regular use, as well as other faults. Diagnostic and prognostic applications will be deployed on the WRS to ensure its safe, efficient, and correct operation. The diagnostic and prognostic results can be used to enable condition-based maintenance to avoid unplanned outages, and perhaps extend the useful life of the WRS. Diagnosis involves detecting when a fault occurs, isolating the root cause of the fault, and identifying the extent of damage. Prognosis involves predicting when the system will reach its end of life irrespective of whether an abnormal condition is present or not. In this paper, first, we develop a physics model of both nominal and faulty system behavior of the WRS. Then, we apply an integrated model-based diagnosis and prognosis framework to the simulation model of the WRS for several different fault scenarios to detect, isolate, and identify faults, and predict the end of life in each fault scenario, and present the experimental results.

A case for closed-loop recycling of post-consumer PET for automotive foams.

PubMed

Bedell, Matthew; Brown, Matthew; Kiziltas, Alper; Mielewski, Deborah; Mukerjee, Shakti; Tabor, Rick

2018-01-01

Striving to utilize sustainable material sources, polyester polyols made via glycolysis and esterification of recycled polyethylene terephthalate (rPET) scrap were used to synthesize flexible polyurethane (PU) foams typically found in automotive interior applications. The objective of this endeavor was to ascertain if a closed-loop model could be established with the discarded PET feedstock. In five separate formulations, up to 50% of the total polyol content (traditionally derived from petroleum-based feedstock) was replaced with the afore-mentioned sustainable recycled polyols. These foams underwent mechanical, thermal, morphological, and physical characterization testing to determine feasibility for use in an automotive interior. Young's modulus, tensile stress at maximum load, tear resistance, and compression modulus all increased by combined averages of 121%, 67%, 32%, and 150% over the control petroleum-based formulation, respectively, in foams possessing 50% rPET polyol content. Thermal stability also increased with sustainable polyol content; thermogravimetric analysis showed that 50% mass loss temperature increased by an average of 20 °C in foams containing 30% recycled polyol. Properties of density and SAG factor remained within 5% of the control petroleum-based reference foams. After comparing these findings to traditional polyols, a compelling argument can be made for the use of post-consumer automotive and industrial feedstocks in developing high-performing interior automotive PU foams. Copyright © 2017 Elsevier Ltd. All rights reserved.

Asphalt recycling technology: Literature review and research plan

NASA Astrophysics Data System (ADS)

Newcomb, D. E.; Epps, J. A.

1981-06-01

A review of current technology for the rehabilitation and maintenance of pavement surfaces by recycling was conducted. While the primary concern was asphalt concrete recycling, a brief review of portland cement concrete recycling is included. Reports of cases involving recycling technology and lessons learned are reviewed. Recommendations are presented outlining research required to advance the state-of-the-art in a manner that will permit the U.S. Air Force to fully attain the benefits of recycling technology.

The Life Cycle Cost (LCC) of Life Support Recycling and Resupply

NASA Technical Reports Server (NTRS)

Jones, Harry W.

2015-01-01

Brief human space missions supply all the crew's water and oxygen from Earth. The multiyear International Space Station (ISS) program instead uses physicochemical life support systems to recycle water and oxygen. This paper compares the Life Cycle Cost (LCC) of recycling to the LCC of resupply for potential future long duration human space missions. Recycling systems have high initial development costs but relatively low durationdependent support costs. This means that recycling is more cost effective for longer missions. Resupplying all the water and oxygen requires little initial development cost but has a much higher launch mass and launch cost. The cost of resupply increases as the mission duration increases. Resupply is therefore more cost effective than recycling for shorter missions. A recycling system pays for itself when the resupply LCC grows greater over time than the recycling LCC. The time when this occurs is called the recycling breakeven date. Recycling will cost very much less than resupply for long duration missions within the Earth-Moon system, such as a future space station or Moon base. But recycling would cost about the same as resupply for long duration deep space missions, such as a Mars trip. Because it is not possible to provide emergency supplies or quick return options on the way to Mars, more expensive redundant recycling systems will be needed.

Cost effectiveness of recycling: A systems model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tonjes, David J., E-mail: david.tonjes@stonybrook.edu; Waste Reduction and Management Institute, School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY 11794-5000; Center for Bioenergy Research and Development, Advanced Energy Research and Technology Center, Stony Brook University, 1000 Innovation Rd., Stony Brook, NY 11794-6044

Highlights: • Curbside collection of recyclables reduces overall system costs over a range of conditions. • When avoided costs for recyclables are large, even high collection costs are supported. • When avoided costs for recyclables are not great, there are reduced opportunities for savings. • For common waste compositions, maximizing curbside recyclables collection always saves money. - Abstract: Financial analytical models of waste management systems have often found that recycling costs exceed direct benefits, and in order to economically justify recycling activities, externalities such as household expenses or environmental impacts must be invoked. Certain more empirically based studies have alsomore » found that recycling is more expensive than disposal. Other work, both through models and surveys, have found differently. Here we present an empirical systems model, largely drawn from a suburban Long Island municipality. The model accounts for changes in distribution of effort as recycling tonnages displace disposal tonnages, and the seven different cases examined all show that curbside collection programs that manage up to between 31% and 37% of the waste stream should result in overall system savings. These savings accrue partially because of assumed cost differences in tip fees for recyclables and disposed wastes, and also because recycling can result in a more efficient, cost-effective collection program. These results imply that increases in recycling are justifiable due to cost-savings alone, not on more difficult to measure factors that may not impact program budgets.« less

Recycle Alaska: Reduce, Reuse, Recycle. Activities Handbook, Teacher's Guide, and Student Worksheets.

ERIC Educational Resources Information Center

Alaska State Dept. of Education, Juneau.

Recycling is a very important aspect of conserving the environment for future generations. This guide addresses the topic of litter prevention for the Alaskan environment and contains 42 activities. Activity topics covered include Natural Cycles, Human Interruption of Natural Cycles, Reduce, Reuse, Recycle and Recycled Classroom. Grade level,…

Contribution of cooperative sector recycling to greenhouse gas emissions reduction: a case study of Ribeirão Pires, Brazil.

PubMed

King, Megan F; Gutberlet, Jutta

2013-12-01

Solid waste, including municipal waste and its management, is a major challenge for most cities and among the key contributors to climate change. Greenhouse gas emissions can be reduced through recovery and recycling of resources from the municipal solid waste stream. In São Paulo, Brazil, recycling cooperatives play a crucial role in providing recycling services including collection, separation, cleaning, stocking, and sale of recyclable resources. The present research attempts to measure the greenhouse gas emission reductions achieved by the recycling cooperative Cooperpires, as well as highlight its socioeconomic benefits. Methods include participant observation, structured interviews, questionnaire application, and greenhouse gas accounting of recycling using a Clean Development Mechanism methodology. The results show that recycling cooperatives can achieve important energy savings and reductions in greenhouse gas emissions, and suggest there is an opportunity for Cooperpires and other similar recycling groups to participate in the carbon credit market. Based on these findings, the authors created a simple greenhouse gas accounting calculator for recyclers to estimate their emissions reductions. Copyright © 2013 Elsevier Ltd. All rights reserved.

Src regulates sequence-dependent beta-2 adrenergic receptor recycling via cortactin phosphorylation*

PubMed Central

Vistein, Rachel; Puthenveedu, Manojkumar A.

2014-01-01

The recycling of internalized signaling receptors, which has direct functional consequences, is subject to multiple sequence and biochemical requirements. Why signaling receptors recycle via a specialized pathway, unlike many other proteins that recycle by bulk, is a fundamental unanswered question. Here we show that these specialized pathways allow selective control of signaling receptor recycling by heterologous signaling. Using assays to visualize receptor recycling in living cells, we show that the recycling of the beta-2 adrenergic receptor (B2AR), a prototypic signaling receptor, is regulated by Src family kinases. The target of Src is cortactin, an essential factor for B2AR sorting into specialized recycling microdomains on the endosome. Phosphorylation of a single cortactin residue, Y466, regulates the rate of fission of B2AR recycling vesicles from these microdomains, and, therefore, the rate of delivery of B2AR to the cell surface. Together, our results indicate that actin-stabilized microdomains that mediate signaling receptor recycling can serve as a functional point of convergence for crosstalk between signaling pathways. PMID:25077552

The fast-recycling receptor Megalin defines the apical recycling pathway of epithelial cells

PubMed Central

Perez Bay, Andres E.; Schreiner, Ryan; Benedicto, Ignacio; Paz Marzolo, Maria; Banfelder, Jason; Weinstein, Alan M.; Rodriguez-Boulan, Enrique J.

2016-01-01

The basolateral recycling and transcytotic pathways of epithelial cells were previously defined using markers such as transferrin (TfR) and polymeric IgA (pIgR) receptors. In contrast, our knowledge of the apical recycling pathway remains fragmentary. Here we utilize quantitative live-imaging and mathematical modelling to outline the recycling pathway of Megalin (LRP-2), an apical receptor with key developmental and renal functions, in MDCK cells. We show that, like TfR, Megalin is a long-lived and fast-recycling receptor. Megalin enters polarized MDCK cells through segregated apical sorting endosomes and subsequently intersects the TfR and pIgR pathways at a perinuclear Rab11-negative compartment termed common recycling endosomes (CRE). Whereas TfR recycles to the basolateral membrane from CRE, Megalin, like pIgR, traffics to subapical Rab11-positive apical recycling endosomes (ARE) and reaches the apical membrane in a microtubule- and Rab11-dependent manner. Hence, Megalin defines the apical recycling pathway of epithelia, with CRE as its apical sorting station. PMID:27180806

Synaptic activity regulates AMPA receptor trafficking through different recycling pathways

PubMed Central

Zheng, Ning; Jeyifous, Okunola; Munro, Charlotte; Montgomery, Johanna M; Green, William N

2015-01-01

Changes in glutamatergic synaptic strength in brain are dependent on AMPA-type glutamate receptor (AMPAR) recycling, which is assumed to occur through a single local pathway. In this study, we present evidence that AMPAR recycling occurs through different pathways regulated by synaptic activity. Without synaptic stimulation, most AMPARs recycled in dynamin-independent endosomes containing the GTPase, Arf6. Few AMPARs recycled in dynamin-dependent endosomes labeled by transferrin receptors (TfRs). AMPAR recycling was blocked by alterations in the GTPase, TC10, which co-localized with Arf6 endosomes. TC10 mutants that reduced AMPAR recycling had no effect on increased AMPAR levels with long-term potentiation (LTP) and little effect on decreased AMPAR levels with long-term depression. However, internalized AMPAR levels in TfR-containing recycling endosomes increased after LTP, indicating increased AMPAR recycling through the dynamin-dependent pathway with synaptic plasticity. LTP-induced AMPAR endocytosis is inconsistent with local recycling as a source of increased surface receptors, suggesting AMPARs are trafficked from other sites. DOI: http://dx.doi.org/10.7554/eLife.06878.001 PMID:25970033

Behaviour of Recycled Coarse Aggregate Concrete: Age and Successive Recycling

NASA Astrophysics Data System (ADS)

Sahoo, Kirtikanta; Pathappilly, Robin Davis; Sarkar, Pradip

2016-06-01

Recycled Coarse Aggregate (RCA) concrete construction technique can be called as `green concrete', as it minimizes the environmental hazard of the concrete waste disposal. Indian standard recommends target mean compressive strength of the conventional concrete in terms of water cement ratio ( w/ c). The present work is an attempt to study the behaviour of RCA concrete from two samples of parent concrete having different age group with regard to the relationship of compressive strength with water cement ratios. Number of recycling may influence the mechanical properties of RCA concrete. The influence of age and successive recycling on the properties such as capillary water absorption, drying shrinkage strain, air content, flexural strength and tensile splitting strength of the RCA concrete are examined. The relationship between compressive strength at different w/ c ratios obtained experimentally is investigated for the two parameters such as age of parent concrete and successive recycling. The recycled concrete using older recycled aggregate shows poor quality. While the compressive strength reduces with successive recycling gradually, the capillary water absorption increases abruptly, which leads to the conclusion that further recycling may not be advisable.

Gender perspective on the factors predicting recycling behavior: Implications from the theory of planned behavior.

PubMed

Oztekin, Ceren; Teksöz, Gaye; Pamuk, Savas; Sahin, Elvan; Kilic, Dilek Sultan

2017-04-01

This study aimed to assess the role of some socio-psychological attributes in explaining recycling behavior of Turkish university community from a gender perspective within the context of the theory of planned behavior with an additional variable (past experience). The recycling behavior of whole sample, females and males, has been examined in 3 sessions -depending on the arguments that explain gendered pattern of private and public environmental behavior and sticking to the fact why females' stronger environmental values, beliefs, and attitudes do not translate consistently into greater engagement in public behavior. As a result of model runs, different variables shaping intention for behavior have been found, namely perceived behavior control for females and past behavior for males. Due to the low percent of the variance in explaining recycling behavior of females, they have been identified as the ones who do not carry out intentions (non-recyclers). Since intentions alone are capable of identifying recyclers accurately but not non-recyclers, there may be other factors to be considered to understand the reason for females not carrying out the intentions. The results of descriptive statistics supported the identification by attitudes toward recycling. Female attitudes were innate (recycling is good, necessary, useful and sensitive), whereas those of males were learnt (recycling is healthy, valuable and correct). Thus, it has been concluded that males' intention for recycling is shaped by their past behavior and the conclusion is supported by males having learnt attitude toward recycling whereas females' lack of intention for recycling is shaped by their perceived behavior control and is supported by their innate attitude for recycling. All in all, the results of the present study provide further support for the utility of the TPB as a model of behavioral prediction and concur with other studies examining the utility of the TPB in the context of recycling. Copyright © 2016 Elsevier Ltd. All rights reserved.

Steel can recycling: how to cut costs and support the environment.

PubMed

Crawford, G

1995-01-01

This is the first in a series of three articles regarding steel can recycling from foodservice operations of healthcare facilities. This article highlights the benefits of recycling and how steel is recycled across the country; the second will focus on the basic methods of recycling steel cans, and will include information on conducting a waste audit and negotiating with a hauler; the final article will convey a case history of actual foodservice recycling practice from a healthcare facility.

Life cycle assessment of a household solid waste source separation programme: a Swedish case study.

PubMed

Bernstad, Anna; la Cour Jansen, Jes; Aspegren, Henrik

2011-10-01

The environmental impact of an extended property close source-separation system for solid household waste (i.e., a systems for collection of recyclables from domestic properties) is investigated in a residential area in southern Sweden. Since 2001, households have been able to source-separate waste into six fractions of dry recyclables and food waste sorting. The current system was evaluated using the EASEWASTE life cycle assessment tool. Current status is compared with an ideal scenario in which households display perfect source-separation behaviour and a scenario without any material recycling. Results show that current recycling provides substantial environmental benefits compared to a non-recycling alternative. The environmental benefit varies greatly between recyclable fractions, and the recyclables currently most frequently source-separated by households are often not the most beneficial from an environmental perspective. With optimal source-separation of all recyclables, the current net contribution to global warming could be changed to a net-avoidance while current avoidance of nutrient enrichment, acidification and photochemical ozone formation could be doubled. Sensitivity analyses show that the type of energy substituted by incineration of non-recycled waste, as well as energy used in recycling processes and in the production of materials substituted by waste recycling, is of high relevance for the attained results.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chi Xinwen, E-mail: x.chi@pgrad.unimelb.edu.au; Streicher-Porte, Martin; Wang, Mark Y.L.

Informal recycling is a new and expanding low cost recycling practice in managing Waste Electrical and Electronic Equipment (WEEE or e-waste). It occurs in many developing countries, including China, where current gaps in environmental management, high demand for second-hand electronic appliances and the norm of selling e-waste to individual collectors encourage the growth of a strong informal recycling sector. This paper gathers information on informal e-waste management, takes a look at its particular manifestations in China and identifies some of the main difficulties of the current Chinese approach. Informal e-waste recycling is not only associated with serious environmental and healthmore » impacts, but also the supply deficiency of formal recyclers and the safety problems of remanufactured electronic products. Experiences already show that simply prohibiting or competing with the informal collectors and informal recyclers is not an effective solution. New formal e-waste recycling systems should take existing informal sectors into account, and more policies need to be made to improve recycling rates, working conditions and the efficiency of involved informal players. A key issue for China's e-waste management is how to set up incentives for informal recyclers so as to reduce improper recycling activities and to divert more e-waste flow into the formal recycling sector.« less

Experimental investigation of photocatalytic effects of concrete in air purification adopting entire concrete waste reuse model.

PubMed

Xu, Yidong; Chen, Wei; Jin, Ruoyu; Shen, Jiansheng; Smallbone, Kirsty; Yan, Chunyang; Hu, Lei

2018-07-05

This research investigated the capacities of recycled aggregate concrete adopting entire concrete waste reuse model in degrading NO 2. Two major issues within environmental sustainability were addressed: concrete waste reuse rate and mitigation of hazards substances in the polluted air. The study consisted of two stages: identification of proper replacement rates of recycled concrete wastes in new concrete mixture design, and the evaluation of photocatalytic performance of recycled aggregate concrete in degrading NO 2 . It was found that replacement rates up to 3%, 30%, and 50% for recycled power, recycled fine aggregate, and recycled coarse aggregate respectively could be applied in concrete mixture design without deteriorating concrete strength. Recycled aggregates contained both positive attributes ("internal curing") and negative effects (e.g., lower hardness) to concrete properties. It was found that 30%-50% of natural coarse aggregate replaced by recycled coarse aggregates coated with TiO 2 would significantly improve the photocatalytic performance of concrete measured by degradation rate of NO 2 . Micro-structures of recycled aggregates observed under microscope indicated that soaking recycled aggregates in TiO 2 solution resulted in whiskers that filled the porosity within recycled aggregates which enhanced concrete strength. Copyright © 2018 Elsevier B.V. All rights reserved.

Recycling Mentors: an intergenerational, service-learning program to promote recycling and environmental awareness.

PubMed

D'abundo, Michelle L; Fugate-Whitlock, Elizabeth I; Fiala, Kelly A

2011-01-01

The purpose of Recycling Mentors was to implement an intergenerational, service-learning program focused on promoting recycling and environmental awareness among students enrolled in Community Health (HEA 301) and Current Issues in Gerontology (GRN 440/540) and adults older than 60 years. Recycling Mentors was conducted in New Hanover County (NHC), North Carolina, where a moderate climate and coastal location attracts many tourists, retirees, and college students. A community like NHC is a good place to implement service-learning that educates both students and older adults about the benefits of recycling to individual health and the environment. During the Fall 2009 semester, undergraduate and graduate students completed institutional review board training and then conducted the program with older adults. The education component of Recycling Mentors included a pre/post survey, brochure, and scheduled visits. Overall, Recycling Mentors was positive service-learning experience with students identifying salient outcomes such as learning about recycling and the environment and working with older adults. In addition, teaching the education component of Recycling Mentors was good practice for students who will be the future health professionals. While service-learning and environmentally themed projects are common, a program that combines the 2 like Recycling Mentors is unique and has the potential to motivate individual change while positively impacting the local community and the environment.

Multi-stakeholder policy modeling for collection and recycling of spent portable battery waste.

PubMed

Gupta, Vimal Kumar; Kaushal, Rajendra Kumar; Shukla, Sheo Prasad

2018-06-01

Policies have been structured for collection and recycling of spent portable battery waste within a framework of stakeholders (recycling council body, producer, recycler and consumer) especially for those battery units that are discarded worldwide because of their expensive cost of recycling. Applicability of stakeholders' policies in their coalition framework have been reviewed and critically analyzed using the Shapley value of cooperative game theory models. Coalition models for 'manufacturer and recycler' indicated the dominating role of manufacturers over the recyclers, and waste management is highly influenced by producer responsibility. But, the take-back policy enables recyclers' dominance role in the management and yields maximum benefit to both recyclers and consumers. The polluter pays principle has been implemented in formulating policies to key stakeholders, 'manufacturers' as well as 'consumers', of battery products by the introduction of penalties to encourage their willingness to join the Environment, Health and Safety program. Results indicated that the policies of the framework have the potential to be implemented within a marginal rise in battery price by 12% to 14.3% in the range of recycling cost per tonne of US$2000 to US$5000. The policy of the stakeholders' framework presented in the study could be an important aid to achieve high collection and recycling rates of spent portable batteries.

Research and Development of a New Waste Collection Bin to Facilitate Education in Plastic Recycling

ERIC Educational Resources Information Center

Chow, Cheuk-fai; So, Wing-Mui Winnie; Cheung, Tsz-Yan

2016-01-01

Plastic recycling has been an alternative method for solid waste management apart from landfill and incineration. However, recycling quality is affected when all plastics are discarded into a single recycling bin that increases cross contaminations and operation cost to the recycling industry. Following the engineering design process, a new…

A Model Recycling Program: UNC Takes Action as Landfill Space Shrinks and Costs Rise.

ERIC Educational Resources Information Center

Sherman, Rhonda L.

1991-01-01

The University of North Carolina responded to escalating waste disposal costs and shrinking landfill space with a structured program of recycling, including a mobile recycling drop, student family housing recycling, a newspaper drop-off site, high-volume glass pick-up, high-volume newspaper pick-up, and cardboard recycling. Campus-wide cooperation…

40 CFR 260.43 - Legitimate recycling of hazardous secondary materials regulated under § 260.34, § 261.2(a)(2)(ii...

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 26 2011-07-01 2011-07-01 false Legitimate recycling of hazardous... (CONTINUED) HAZARDOUS WASTE MANAGEMENT SYSTEM: GENERAL Rulemaking Petitions § 260.43 Legitimate recycling of... demonstrate that the recycling is legitimate. Hazardous secondary material that is not legitimately recycled...

40 CFR 260.43 - Legitimate recycling of hazardous secondary materials regulated under § 260.34, § 261.2(a)(2)(ii...

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 27 2013-07-01 2013-07-01 false Legitimate recycling of hazardous... (CONTINUED) HAZARDOUS WASTE MANAGEMENT SYSTEM: GENERAL Rulemaking Petitions § 260.43 Legitimate recycling of... demonstrate that the recycling is legitimate. Hazardous secondary material that is not legitimately recycled...

40 CFR 260.43 - Legitimate recycling of hazardous secondary materials regulated under § 260.34, § 261.2(a)(2)(ii...

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 27 2012-07-01 2012-07-01 false Legitimate recycling of hazardous... (CONTINUED) HAZARDOUS WASTE MANAGEMENT SYSTEM: GENERAL Rulemaking Petitions § 260.43 Legitimate recycling of... demonstrate that the recycling is legitimate. Hazardous secondary material that is not legitimately recycled...

40 CFR 260.43 - Legitimate recycling of hazardous secondary materials regulated under § 260.34, § 261.2(a)(2)(ii...

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 26 2014-07-01 2014-07-01 false Legitimate recycling of hazardous... (CONTINUED) HAZARDOUS WASTE MANAGEMENT SYSTEM: GENERAL Rulemaking Petitions § 260.43 Legitimate recycling of... demonstrate that the recycling is legitimate. Hazardous secondary material that is not legitimately recycled...

40 CFR 260.43 - Legitimate recycling of hazardous secondary materials regulated under § 260.34, § 261.2(a)(2)(ii...

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Legitimate recycling of hazardous... (CONTINUED) HAZARDOUS WASTE MANAGEMENT SYSTEM: GENERAL Rulemaking Petitions § 260.43 Legitimate recycling of... demonstrate that the recycling is legitimate. Hazardous secondary material that is not legitimately recycled...

An investigation of sustainable and recyclable composites for structural applications

NASA Astrophysics Data System (ADS)

Moller, Johannes Paul

Motivated by the need for more sustainable materials in general and the issues concerning the life cycle of wind turbine blades in particular, the focus of this research work is to better understand what is needed to create high-performance bio-epoxy composites, and to explore their repair and recycling. To further these ends, glass fiber reinforced composites were manufactured using an epoxidized linseed oil (ELO) based matrix cured with various anhydride curatives and catalysts. Based on mechanical properties measurements of these materials, ELO cured with methyltetrahydrophthalic anhydride (MTHPA) and catalyzed with 2-ethyl-4-methylimidazole (2E4MI) yielded the best performance among all fou iulations tested, and avoided the void foiniation issues associated with the use of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) as a catalyst. In addition to the mechanical characterization of the composite, the applicability and processability of a range of bio-epoxy formulations was evaluated in the context of for vacuum-assisted resin transfer molding (VARTM). In particular, a new methodology for assessing the infusability of a resin was developed and the bioepoxy formulations were demonstrated to be more amenable to resin infusion than a conventional control. Having demonstrated the potential for bio-based resins to produce more sustainable high-performance composites, further studies were carried out to address end-of-life issues. Here different approaches for healing and recycling of epoxy vitrimers (epoxies rendered reworkable by the inclusion of a transesterification catalyst) and their composites were introduced and proof-of-concept experiments were performed. By exposing a fractured glass fiber epoxy vitrimer composite to elevated temperatures and pressure for times on the order often minutes, a healing efficiency of 55% was achieved. Additionally, two different recycling approaches were explored. First, mechnical recycling (grinding followed by reconsolidation via compression molding) was successfully demonstrated for epoxy vitrimers and epoxy vitrimer composites. Dynamic thermomechanical and quasi-static tensile data vs. particle size indicate that the finest powder yielded the best results. In addition to mechanical recycling, a new approach to chemical recycling via fiber reclamation was introduced. Here, removal of the matrix was achieved via high temperature transesterification of the resin in a large excess of an alcohol solvent, and new continuously reinforced composites were succesfully prepared from the reclaimed fibers.

Formulation and preparation of Hanford Waste Treatment Plant direct feed low activity waste Effluent Management Facility core simulant

DOE Office of Scientific and Technical Information (OSTI.GOV)

McCabe, Daniel J.; Nash, Charles A.; Adamson, Duane J.

The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream (LAW Melter Off-Gas Condensate, LMOGC) from the off-gas system. The baseline plan for disposition of this stream during full WTP operations is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility. However, during the Direct Feed LAW (DFLAW) scenario, planned disposition of this stream is to evaporate it in a new evaporator in the Effluent Management Facility (EMF) and then return it tomore » the LAW melter. It is important to understand the composition of the effluents from the melter and new evaporator so that the disposition of these streams can be accurately planned and accommodated. Furthermore, alternate disposition of the LMOGC stream would eliminate recycling of problematic components, and would enable less integrated operation of the LAW melter and the Pretreatment Facilities. Alternate disposition would also eliminate this stream from recycling within WTP when it begins operations and would decrease the LAW vitrification mission duration and quantity of glass waste, amongst the other problems such a recycle stream present. This LAW Melter Off-Gas Condensate stream will contain components that are volatile at melter temperatures and are problematic for the glass waste form, such as halides and sulfate. Because this stream will recycle within WTP, these components accumulate in the Melter Condensate stream, exacerbating their impact on the number of LAW glass containers that must be produced. Diverting the stream reduces the halides and sulfate in the recycled Condensate and is a key outcome of this work. This overall program examines the potential treatment and immobilization of this stream to enable alternative disposal. The objective of this task was to formulate and prepare a simulant of the LAW Melter Off-gas Condensate expected during DFLAW operations. That simulant can be used in evaporator testing to predict the composition of the effluents from the Effluent Management Facility (EMF) evaporator to aid in planning for their disposition. This document describes the method used to formulate a simulant of this LAW Melter Off-Gas Condensate stream, which, after pH adjustment, is the feed to the evaporator in the EMF.« less

Looking North at Uranium recovery Recycle Tanks in Red Room ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Looking North at Uranium recovery Recycle Tanks in Red Room in Recycle Recovery Building - Hematite Fuel Fabrication Facility, Recycle Recovery Building, 3300 State Road P, Festus, Jefferson County, MO

40 CFR Appendix J to Subpart G of... - Substitutes listed in the January 29, 2002 Final Rule, effective April 1, 2002

Code of Federal Regulations, 2012 CFR

2012-07-01

... from the fire protection system in conjunction with testing or servicing, and recycled for later use or... protective equipment (e.g., respiratory protection), fire protection, hazard communication, worker training...

40 CFR Appendix J to Subpart G of... - Substitutes listed in the January 29, 2002 Final Rule, effective April 1, 2002

Code of Federal Regulations, 2013 CFR

2013-07-01

... from the fire protection system in conjunction with testing or servicing, and recycled for later use or... protective equipment (e.g., respiratory protection), fire protection, hazard communication, worker training...

40 CFR Appendix J to Subpart G of... - Substitutes listed in the January 29, 2002 Final Rule, effective April 1, 2002

Code of Federal Regulations, 2014 CFR

2014-07-01

... from the fire protection system in conjunction with testing or servicing, and recycled for later use or... protective equipment (e.g., respiratory protection), fire protection, hazard communication, worker training...

Evaluation of waste concrete road materials for use in oyster aquaculture.

DOT National Transportation Integrated Search

2013-02-01

The primary objective of this study was to determine the suitability of recycled concrete : aggregate (RCA) from road projects as bottom conditioning material for on-bottom oyster : aquaculture in the Chesapeake Bay. The testing was designed to (1) e...

Testing protocols to ensure performance of high asphalt binder replacement mixes using RAP and RAS.

DOT National Transportation Integrated Search

2015-12-01

The use of reclaimed asphalt pavement (RAP) and recycled asphalt shingles (RAS) in asphalt concrete (AC) mixtures can reduce demand for virgin aggregates and asphalt binder, bringing environmental and economic benefits. However, replacing virgin asph...

Pricing Models for Dual-channel Reverse Supply Chain Considering Regional Differences under “Internet Recycling” Mode in China

NASA Astrophysics Data System (ADS)

Wu, Di; Li, Peng; Chen, Juhong

2018-01-01

In recent years, the Internet technology has been deeply influencing recycling industry to make it more intelligent and interconnected. However, most existing papers on “Internet Recycling” neglected the problem of pricing strategy under online and offline channels for different levels of recyclers. Moreover, the effect of regional differences has been emphasized a lot in dual-channel forward supply chain, but recycling field has seldom been concerned about it. In this paper, a recycling system consisting of one recycling center and several third-party recyclers (TPR) was investigated based on traditional mode and dual-channel mode. The dual-channel reverse supply chain model is transformed from traditional mode by the introduction of online channel. It involves two recycling modes, as recycling centre for online recovery and “Recycling center+TPR” for offline recovery. By establishing pricing strategies based on Stackelberg game model, the impacts of regional differences were analysed. Finally, numerical analysis was given to illustrate the effectiveness of the pricing mechanisms and strategies.

Attitudes toward text recycling in academic writing across disciplines.

PubMed

Hall, Susanne; Moskovitz, Cary; Pemberton, Michael A

2018-01-01

Text recycling, the reuse of material from one's own previously published writing in a new text without attribution, is a common academic writing practice that is not yet well understood. While some studies of text recycling in academic writing have been published, no previous study has focused on scholars' attitudes toward text recycling. This article presents results from a survey of over 300 journal editors and editorial board members from 86 top English-language journals in 16 different academic fields regarding text recycling in scholarly articles. Responses indicate that a large majority of academic gatekeepers believe text recycling is allowable in some circumstances; however, there is a lack of clear consensus about when text recycling is or is not appropriate. Opinions varied according to the source of the recycled material, its structural location and rhetorical purpose, and conditions of authorship conditions-as well as by the level of experience as a journal editor. Our study suggests the need for further research on text recycling utilizing focus groups and interviews.

Study on Consumer Opposition to Exporting Recyclable Wastes

NASA Astrophysics Data System (ADS)

Suzuki, Yoshiyuki; Koizumi, Kunishige; Zhou, Weisheng

Trans-boundary trade from Japan to China of recyclable wastes such as waste copper has increased rapidly, because of resource demands through economic growth. These wastes are recycled at high rates thanks to the Chinese manual recycling process by a lot of low wage migrant workers from rural districts. China benefits by supplying jobs to many migrant workers and getting cheap resources. Although, Japanese consumers may have some opposition to exporting end-of-pipe home appliance wastes to foreign countries. From the results of the path-analysis from the questionnaire to Japanese consumers, it became clear that their reluctance came from anxiety about illegal dumping, the labor environment at the import country and the destruction of the ecosystem. Through conjoint analysis, willingness to pay the recycling fee decreases - 1,625 yen (equal to 34% of the current recycling fee of 4,630 yen) when choosing global recycling as opposed to domestic recycling, hypothesizing that consumers would rather recycle domestically instead of globally.

A survey of recycling behaviour in households in Dhaka, Bangladesh.

PubMed

Afroz, Rafia; Hanaki, Keisuke; Tuddin, Rabaah; Ayupp, Kartinah; Ayup, Kartinah

2010-06-01

This paper examines the factors that might influence recycling behaviour of the households in Dhaka city, Bangladesh. Information on recycling activity, socio-economic characteristics, and attitudes of the households towards recycling were obtained from interviews with 456 households in Dhaka. Logistic regression analysis was used to determine the dominant factors that might influence the recycling behaviour of the households. The results showed that environmental consciousness, the availability of storage space, and age (25-35 years) are significant positive predictors of recycling behaviour (at the 1% level). Another variable Income 2 (TK3,000-15,000) is also positively correlated with recycling (at the 5% level). Establishment of a recycling programme could be an effective strategy in implementing sustainable waste management in Bangladesh. For this strategy to succeed, however, active partnership between households and the waste management service department is required. The households' attitudes toward recycling should, therefore, be taken into consideration as should the results of this study, which are important indicators of households' positive attitudes toward sustainable waste management in Dhaka.

Recycled material availability in Maryland - a synthesis study.

DOT National Transportation Integrated Search

2016-10-01

There is growing interest in using recycled materials in highway construction nationwide. The research study focused : on four types of recycled materials: recycled concrete aggregate (RCA), reclaimed asphalt pavement (RAP), dredged : materials, and ...

Feasibility of recycling rubber-modified paving materials.

DOT National Transportation Integrated Search

2005-02-01

Recycling has proved to be a sound, economical method of conserving and reusing scarce material resources used in AC pavement construction. Considerable experience with recycling conventional AC mixtures indicates that the resulting recycled pavement...

Recycling.

ERIC Educational Resources Information Center

Sinker, Barbara

1986-01-01

Discusses the range of benefits resulting from recycling efforts and projects. Presents information and data related to the recycling of metals, cans, paper, fans, and plastics. Suggestions for motivating and involving youth in recycling programs are also offered. (ML)

Additive Manufacturing of Syntactic Foams: Part 1: Development, Properties, and Recycling Potential of Filaments

NASA Astrophysics Data System (ADS)

Singh, Ashish Kumar; Patil, Balu; Hoffmann, Niklas; Saltonstall, Brooks; Doddamani, Mrityunjay; Gupta, Nikhil

2018-03-01

This work focuses on developing filaments of high-density polyethylene (HDPE) and their hollow particle-filled syntactic foams for commercial three-dimensional (3D) printers based on fused filament fabrication technology. Hollow fly-ash cenospheres were blended by 40 wt.% in a HDPE matrix to produce syntactic foam (HDPE40) filaments. Further, the recycling potential was studied by pelletizing the filaments again to extrude twice (2×) and three times (3×). The filaments were tensile tested at 10-4 s-1, 10-3 s-1, and 10-2 s-1 strain rates. HDPE40 filaments show an increasing trend in modulus and strength with the strain rate. Higher density and modulus were noticed for 2× filaments compared to 1× filaments because of the crushing of some cenospheres in the extrusion cycle. However, 2× and 3× filament densities are nearly the same, showing potential for recycling them. The filaments show better properties than the same materials processed by conventional injection molding. Micro-CT scans show a uniform dispersion of cenospheres in all filaments.

Co-recycling of acrylonitrile-butadiene-styrene waste plastic and nonmetal particles from waste printed circuit boards to manufacture reproduction composites.

PubMed

Sun, Zhixing; Shen, Zhigang; Zhang, Xiaojing; Ma, Shulin

2015-01-01

This study investigated the feasibility of using acrylonitrile-butadiene-styrene (ABS) waste plastic and nonmetal particles from waste printed circuit boards (WPCB) to manufacture reproduction composites (RC), with the aim of co-recycling these two waste resources. The composites were prepared in a twin-crew extruder and investigated by means of mechanical testing, in situ flexural observation, thermogravimatric analysis, and dimensional stability evaluation. The results showed that the presence of nonmetal particles significantly improved the mechanical properties and the physical performance of the RC. A loading of 30 wt% nonmetal particles could achieve a flexural strength of 72.6 MPa, a flexural modulus of 3.57 GPa, and an impact strength of 15.5 kJ/m2. Moreover, it was found that the application of maleic anhydride-grafted ABS as compatilizer could effectively promote the interfacial adhesion between the ABS plastic and the nonmetal particles. This research provides a novel method to reuse waste ABS and WPCB nonmetals for manufacturing high value-added product, which represents a promising way for waste recycling and resolving the environmental problem.

Durability of recycled aggregate concrete using pozzolanic materials.

PubMed

Ann, K Y; Moon, H Y; Kim, Y B; Ryou, J

2008-01-01

In this study, pulverized fuel ash (PFA) and ground granulated blast furnace slag (GGBS) were used to compensate for the loss of strength and durability of concrete containing recycled aggregate. As a result, 30% PFA and 65% GGBS concretes increased the compressive strength to the level of control specimens cast with natural granite gravel, but the tensile strength was still lowered at 28 days. Replacement with PFA and GGBS was effective in raising the resistance to chloride ion penetrability into the concrete body, measured by a rapid chloride ion penetration test based on ASTM C 1202-91. It was found that the corrosion rate of 30% PFA and 65% GGBS concretes was kept at a lower level after corrosion initiation, compared to the control specimens, presumably due to the restriction of oxygen and water access. However, it was less effective in increasing the chloride threshold level for steel corrosion. Hence, it is expected that the corrosion time for 30% PFA and 65% GGBS concrete containing recycled aggregate mostly equates to the corrosion-free life of control specimens.

Health risks of polycyclic aromatic hydrocarbons via fish consumption in Haimen bay (China), downstream of an e-waste recycling site (Guiyu).

PubMed

Shi, Jingchun; Zheng, Gene Jin-Shu; Wong, Ming-Hung; Liang, Hong; Li, Yuelin; Wu, Yinglin; Li, Ping; Liu, Wenhua

2016-05-01

Guiyu, China has been one of the largest e-waste recycling sites of the world for more than 20 years. Abundant data show that local dwellers there suffered from severe health risks from e-waste contaminants. In this study, polycyclic aromatic hydrocarbons (PAHs) were used as candidates to test the contamination levels and their possible adverse effects on residents in Haimen Bay, the estuary of Lian River (less than 30km from Guiyu), which has been totally neglected. The concentrations of 16PAHs were determined in collected marine fish with a median ΣPAH concentration of 1478ng/g (wet weight), and the contamination may be mainly influenced by Lian River runoff, specifically from Guiyu. The lifetime excess cancer risk for local dwellers was much higher than the serious risk level (10(-4)). More seriously, outflows of PAHs from the e-waste recycling site (Guiyu) seemed to exert health risks of a much larger scale of population downstream. Copyright © 2016 Elsevier Inc. All rights reserved.

Optimization of coagulation-flocculation treatment on paper-recycling wastewater: Application of response surface methodology.

PubMed

Birjandi, Noushin; Younesi, Habibollah; Bahramifar, Nader; Ghafari, Shahin; Zinatizadeh, Ali Akbar; Sethupathi, Sumathi

2013-01-01

The application of coagulation-flocculation (CF) process for treating the paper-recycling wastewater in jar-test experiment was employed. The purpose of the study was aimed to examine the efficiency of alum and poly aluminum chloride (PACl) in combination with a cationic polyacrylamide (C-PAM) in removal of chemical oxygen demand (COD) and turbidity from paper-recycling wastewater. Optimization of CF process were performed by varying independent parameters (coagulants dosage, flocculants dosage, initial COD and pH) using a central composite design (CCD) under response surface methodology (RSM). Maximum set required 4.5 as pH, 40 mg/L coagulants dosage and 4.5 mg/L flocculants dosage at which gave 92% reduction of turbidity, 97% of COD removal and SVI 80 mL/g. The best coagulant and flocculants were alum and chemfloc 3876 at dose of 41 and 7.52 mg/L, respectively, correspondingly at pH of 6.85. These conditions gave 91.30% COD and 95.82% turbidity removals and 12 mL/g SVI.

A prototype knowledge-based decision support system for industrial waste management. Part 2: Application to a Trinidadian industrial estate case study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boyle, C.A.; Baetz, B.W.

1998-09-01

A knowledge-based decision support system (KBDSS) has been developed to examine the potentials for reuse, co-treatment, recycling and disposal of wastes from different industrial facilities. Four plants on the Point Lisas Industrial Estate in Trinidad were selected to test this KBDSS; a gas processing plant, a methanol plant, a fertilizer/ammonia plant and a steel processing plant. A total of 77 wastes were produced by the plants (51,481,500 t year{sup {minus}1}) with the majority being released into the ocean or emitted into the air. Seventeen wastes were already being recycled off-site so were not included in the database. Using a knowledgemore » base of 25 possible treatment processes, the KBDSS generated over 4,600 treatment train options for managing the plant wastes. The developed system was able to determine treatment options for the wastes which would minimize the number of treatments and the amount of secondary wastes produced and maximize the potential for reuse, recycling and co-treatment of wastes.« less

Comparison of different methods to include recycling in LCAs of aluminium cans and disposable polystyrene cups.

PubMed

van der Harst, Eugenie; Potting, José; Kroeze, Carolien

2016-02-01

Many methods have been reported and used to include recycling in life cycle assessments (LCAs). This paper evaluates six widely used methods: three substitution methods (i.e. substitution based on equal quality, a correction factor, and alternative material), allocation based on the number of recycling loops, the recycled-content method, and the equal-share method. These six methods were first compared, with an assumed hypothetical 100% recycling rate, for an aluminium can and a disposable polystyrene (PS) cup. The substitution and recycled-content method were next applied with actual rates for recycling, incineration and landfilling for both product systems in selected countries. The six methods differ in their approaches to credit recycling. The three substitution methods stimulate the recyclability of the product and assign credits for the obtained recycled material. The choice to either apply a correction factor, or to account for alternative substituted material has a considerable influence on the LCA results, and is debatable. Nevertheless, we prefer incorporating quality reduction of the recycled material by either a correction factor or an alternative substituted material over simply ignoring quality loss. The allocation-on-number-of-recycling-loops method focusses on the life expectancy of material itself, rather than on a specific separate product. The recycled-content method stimulates the use of recycled material, i.e. credits the use of recycled material in products and ignores the recyclability of the products. The equal-share method is a compromise between the substitution methods and the recycled-content method. The results for the aluminium can follow the underlying philosophies of the methods. The results for the PS cup are additionally influenced by the correction factor or credits for the alternative material accounting for the drop in PS quality, the waste treatment management (recycling rate, incineration rate, landfilling rate), and the source of avoided electricity in case of waste incineration. The results for the PS cup, which are less dominated by production of virgin material than aluminium can, furthermore depend on the environmental impact categories. This stresses the importance to consider other impact categories besides the most commonly used global warming impact. The multitude of available methods complicates the choice of an appropriate method for the LCA practitioner. New guidelines keep appearing and industries also suggest their own preferred method. Unambiguous ISO guidelines, particularly related to sensitivity analysis, would be a great step forward in making more robust LCAs. Copyright © 2015 Elsevier Ltd. All rights reserved.

Information Technology Support in the 8000 Directorate

NASA Technical Reports Server (NTRS)

2004-01-01

My summer internship was spent supporting various projects within the Environmental Management Office and Glenn Safety Office. Mentored by Eli Abumeri, I was trained in areas of Information Technology such as: Servers, printers, scanners, CAD systems, Web, Programming, and Database Management, ODIN (networking, computers, and phones). I worked closely with the Chemical Sampling and Analysis Team (CSAT) to redesign a database to more efficiently manage and maintain data collected for the Drinking Water Program. This Program has been established for over fifteen years here at the Glenn Research Center. It involves the continued testing and retesting of all drinking water dispensers. The quality of the drinking water is of great importance and is determined by comparing the concentration of contaminants in the water with specifications set forth by the Environmental Protection Agency (EPA) in the Safe Drinking Water Act (SDWA) and its 1986 and 1991 amendments. The Drinking Water Program consists of periodic testing of all drinking water fountains and sinks. Each is tested at least once every 2 years for contaminants and naturally occurring species. The EPA's protocol is to collect an initial and a 5 minute draw from each dispenser. The 5 minute draw is what is used for the maximum contaminant level. However, the CS&AT has added a 30 second draw since most individuals do not run the water 5 minutes prior to drinking. This data is then entered into a relational Microsoft Access database. The database allows for the quick retrieval of any test@) done on any dispenser. The data can be queried by building number, date or test type, and test results are documented in an analytical report for employees to read. To aid with the tracking of recycled materials within the lab, my help was enlisted to create a database that could make this process less cumbersome and more efficient. The date of pickup, type of material, weight received, and unit cost per recyclable. This information could then calculate the dollar amount generated by the recycling of certain materials. This database will ultimately prove useful in determining the amounts of materials consumed by the lab and will help serve as an indicator potential overuse.

Organic compounds in concrete from demolition works.

PubMed

Van Praagh, M; Modin, H; Trygg, J

2015-11-01

This study aims to verify the effect of physically removing the outer surface of contaminated concrete on total contents and on potential mobility of pollutants by means of leaching tests. Reclaimed concrete from 3 industrial sites in Sweden were included: A tar impregnated military storage, a military tar track-depot, as well as concrete constructions used for disposing of pesticide production surplus and residues. Solid materials and leachates from batch and column leaching tests were analysed for metals, Cl, F, SO4, DOC and contents of suspected organic compounds (polycyclic aromatic hydrocarbons, PAH, and pesticides/substances for pesticide production such as phenoxy acids, chlorophenols and chlorocresols, respectively). In case of PAH contaminated concrete, results indicate that removing 1 or 5 mm of the surface lead to total concentrations below the Swedish guidelines for recycling of aggregates and soil in groundwork constructions. 3 out of 4 concrete samples contaminated with pesticides fulfilled Swedish guidelines for contaminated soil. Results from batch and column leaching tests indicated, however, that concentrations above environmental quality standards for certain PAH and phenoxy acids, respectively, might occur at site when the crushed concrete is recycled in groundwork constructions. As leaching tests engaged in the study deviated from leaching test standards with a limited number of samples, the potential impact of the leaching tests' equipment on measured PAH and pesticide leachate concentrations has to be evaluated in future work. Copyright © 2015. Published by Elsevier Ltd.

40 CFR Appendix C to Subpart B of... - SAE J2788 Standard for Recovery/Recycle and Recovery/Recycle/Recharging Equipment for HFC-134a...

Code of Federal Regulations, 2014 CFR

2014-07-01

... requirements for the recovery/recycling of HFC-134a that has been directly removed from, and is intended for reuse in, mobile air-conditioning systems and recovery/recycling and system recharging of recycled... The purpose of this SAE Standard is to establish the specific minimum equipment performance...

Cell phone recycling experiences in the United States and potential recycling options in Brazil.

PubMed

Silveira, Geraldo T R; Chang, Shoou-Yuh

2010-11-01

This paper presents an overview of cell phone recycling programs currently available in the United States. At the same time, it also provides analyses of the current recycling situation and possible recycling alternatives for Brazil. Although there are several recycling options in the United States, collection rates are still only 10% of all potential devices because customers are not aware of these possibilities. The whole system is financially based on reselling refurbished cell phones and recycled materials to developing countries which represent an effective and strong market. Several recyclers offer funds to collection partners who are either charities or who work with charities while obtaining the materials that they need in order to run their operations. A mobile phone recycling system for Brazil considering the United States experience and the Extended Producer Responsibility (EPR) principle is suggested. A deposit/refund/advance-recycling fee is proposed which might be implemented as a voluntary industrial initiative managed by PRO Brazil, a producer responsibility organization. One widespread public-private agreement will integrate all mobile phone stakeholders, and environmental education actions and promotional events will promote citizen's participation. Copyright © 2010 Elsevier Ltd. All rights reserved.

Investigation of the recycling of tires to elastomeric requirements by techniques of thermal compression

NASA Astrophysics Data System (ADS)

Nadal Gisbert, Antonio V.

In this work is investigated the recycling of tires to elastomeric requirements by thermal compression. The production of recycled products is carried out starting from the powder, of elastomeric nature, coming from the grinding of used tires denominated GTR (Ground Tire Rubber) of different grain size, although the fundamental objective is the recycling of powder of 0,2mm grain size. The process of forming used for obtaining the recycled product is thermal compression, due to its simplicity and low cost. The composition of the powder has been analyzed and also the influence, on the elastomeric characteristics of the recycled product, of different parameters: Grain size, compact pressure, temperature, time, thickness of the recycled product and combination of sizes. At last we give an hypothesis that justifies the mechanism that gives cohesion to the powder GTR and allows their recycling. We also have carried out an analysis of the investigation lines, at the present, on the recycling of tires in general and an economic study of the viability of the recycled product in front of present products in the market, agglomerated with polyurethane, that have their application in using it in different types of floors.

Disposing and recycling waste printed circuit boards: disconnecting, resource recovery, and pollution control.

PubMed

Wang, Jianbo; Xu, Zhenming

2015-01-20

Over the past decades, China has been suffering from negative environmental impacts from distempered e-waste recycling activities. After a decade of effort, disassembly and raw materials recycling of environmentally friendly e-waste have been realized in specialized companies, in China, and law enforcement for illegal activities of e-waste recycling has also been made more and more strict. So up to now, the e-waste recycling in China should be developed toward more depth and refinement to promote industrial production of e-waste resource recovery. Waste printed circuit boards (WPCBs), which are the most complex, hazardous, and valuable components of e-waste, are selected as one typical example in this article that reviews the status of related regulations and technologies of WPCBs recycling, then optimizes, and integrates the proper approaches in existence, while the bottlenecks in the WPCBs recycling system are analyzed, and some preliminary experiments of pinch technologies are also conducted. Finally, in order to provide directional guidance for future development of WPCBs recycling, some key points in the WPCBs recycling system are proposed to point towards a future trend in the e-waste recycling industry.

An Optimization Model for Expired Drug Recycling Logistics Networks and Government Subsidy Policy Design Based on Tri-level Programming

PubMed Central

Huang, Hui; Li, Yuyu; Huang, Bo; Pi, Xing

2015-01-01

In order to recycle and dispose of all people’s expired drugs, the government should design a subsidy policy to stimulate users to return their expired drugs, and drug-stores should take the responsibility of recycling expired drugs, in other words, to be recycling stations. For this purpose it is necessary for the government to select the right recycling stations and treatment stations to optimize the expired drug recycling logistics network and minimize the total costs of recycling and disposal. This paper establishes a tri-level programming model to study how the government can optimize an expired drug recycling logistics network and the appropriate subsidy policies. Furthermore, a Hybrid Genetic Simulated Annealing Algorithm (HGSAA) is proposed to search for the optimal solution of the model. An experiment is discussed to illustrate the good quality of the recycling logistics network and government subsides obtained by the HGSAA. The HGSAA is proven to have the ability to converge on the global optimal solution, and to act as an effective algorithm for solving the optimization problem of expired drug recycling logistics network and government subsidies. PMID:26184252

An Optimization Model for Expired Drug Recycling Logistics Networks and Government Subsidy Policy Design Based on Tri-level Programming.

PubMed

Huang, Hui; Li, Yuyu; Huang, Bo; Pi, Xing

2015-07-09

In order to recycle and dispose of all people's expired drugs, the government should design a subsidy policy to stimulate users to return their expired drugs, and drug-stores should take the responsibility of recycling expired drugs, in other words, to be recycling stations. For this purpose it is necessary for the government to select the right recycling stations and treatment stations to optimize the expired drug recycling logistics network and minimize the total costs of recycling and disposal. This paper establishes a tri-level programming model to study how the government can optimize an expired drug recycling logistics network and the appropriate subsidy policies. Furthermore, a Hybrid Genetic Simulated Annealing Algorithm (HGSAA) is proposed to search for the optimal solution of the model. An experiment is discussed to illustrate the good quality of the recycling logistics network and government subsides obtained by the HGSAA. The HGSAA is proven to have the ability to converge on the global optimal solution, and to act as an effective algorithm for solving the optimization problem of expired drug recycling logistics network and government subsidies.

The potential of financial incentives to enhance householders' kerbside recycling behaviour.

PubMed

Shaw, P J; Maynard, S J

2008-01-01

Although the successful enhancement of householders' participation in kerbside recycling schemes is essential for household waste recycling schemes to reach their desired levels of achievement, our understanding of householders' responses to the various incentives available to waste managers is incomplete. In particular, whether and how the recycling behaviour of householders may be favourably altered through imposition of financial penalties or rewards is not fully understood. Surveys of householders' attitudes in the London Borough of Havering, served by a kerbside co-mingled survival bag recycling scheme, showed they might be better encouraged to recycle more through improvements to structural and promotional aspects of the recycling scheme than through imposition of financial incentives. If financial incentives were to be imposed to enhance kerbside recycling, householders preferred: (1) rewards to penalties, and (2) community-based rewards and local taxation rebates to other or individual rewards. Given the attitudes of householders and the resources that would be needed to monitor their recycling behaviour as a basis for delivering financial incentives, it is suggested that the priority for enhancing recycling should be to make appropriate improvements in the infrastructure and support of the kerbside scheme and service.

Effect of simulated mechanical recycling processes on the structure and properties of poly(lactic acid).

PubMed

Beltrán, F R; Lorenzo, V; Acosta, J; de la Orden, M U; Martínez Urreaga, J

2018-06-15

The aim of this work is to study the effects of different simulated mechanical recycling processes on the structure and properties of PLA. A commercial grade of PLA was melt compounded and compression molded, then subjected to two different recycling processes. The first recycling process consisted of an accelerated ageing and a second melt processing step, while the other recycling process included an accelerated ageing, a demanding washing process and a second melt processing step. The intrinsic viscosity measurements indicate that both recycling processes produce a degradation in PLA, which is more pronounced in the sample subjected to the washing process. DSC results suggest an increase in the mobility of the polymer chains in the recycled materials; however the degree of crystallinity of PLA seems unchanged. The optical, mechanical and gas barrier properties of PLA do not seem to be largely affected by the degradation suffered during the different recycling processes. These results suggest that, despite the degradation of PLA, the impact of the different simulated mechanical recycling processes on the final properties is limited. Thus, the potential use of recycled PLA in packaging applications is not jeopardized. Copyright © 2017 Elsevier Ltd. All rights reserved.