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1

Technical Notes: Multiple-Tank Aquarium System with Recirculating Water for Laboratory Studies of Freshwater Fishes  

Microsoft Academic Search

A recirculating-water aquarium system for laboratory studies of freshwater fishes is described. The system consists of 216 glass tanks (3.5 gal each), two particle filters, a multistage biofilter, two ultraviolet-light sterilizers, and a regenerative blower for auxiliary aeration. Each tank is connected separately to the recirculating-water supply through inflow and outflow manifold pipes. Water flow to individual tanks is adjustable

Roger W. Rottmann; Donald E. Campton

1989-01-01

2

Design and Evaluation of Recirculating Water Systems for Maintenance and Propagation of Freshwater Mussels  

Microsoft Academic Search

A complete system for culturing, rearing, and holding juvenile and adult freshwater mussels (Unionidae) was designed and evaluated for use at hatcheries and research facilities. The system includes air delivery, water conditioning and delivery, algal culturing and automated algal feed delivery, and air-driven water-recirculating units. These systems are appropriate for holding and conditioning adult mussels for spawning, as well as

William F. Henley; Lora L. Zimmerman; Richard J. Neves; Mark R. Kidd

2001-01-01

3

Ozonation of a recirculating rainbow trout culture system II. Effects on microscreen filtration and water quality  

Microsoft Academic Search

Ozone was added to water in a recirculating rainbow trout (Oncorhynchus mykiss) culture system just prior to the culture tanks in order to oxidize nitrite and organic material, improve overall water quality, and assist removal of solids across the microscreen filter. Data from four 8-week studies on ozonation and an 8-week no ozone control indicated that adding ozone reduced the

Steven T. Summerfelt; Joseph A. Hankins; Amy L. Weber; Martin D. Durant

1997-01-01

4

Improving Heating System Operations Using Water Re-Circulation  

E-print Network

In order to solve the imbalance problem of a heating system, brought about by consumer demand and regulation, and save the electricity energy consumed by a circulation pump, a water mixing and pressure difference control heating system is proposed...

Li, F.; Han, J.

2006-01-01

5

Observations on side-swimming rainbow trout Oncorhynchus mykiss in water recirculation aquaculture systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

During a controlled 6-month study using six replicated water recirculation aquaculture systems (WRAS), it was observed that rainbow trout Oncorhynchus mykiss in all WRAS exhibited a higher-than-normal prevalence of side-swimming (i.e. controlled, forward swimming, but with misaligned orientation suc...

6

Water quality and rainbow trout performance in a Danish Model Farm recirculating system: Comparison with a flow through system  

Microsoft Academic Search

The objective was to compare water quality and fish growth and mortality in a pilot scale recirculating system (RS) and a control tank in flow through system (FTS). The RS was designed after the Danish Model Trout Farm and operated with a make up water renewal rate of 9m3kg-1 of fish produced. RS water quality did not decrease significantly with

Emmanuelle Roque d’orbcastel; Jean-Paul Blancheton; Alain Belaud

2009-01-01

7

Flowing recirculated-water system for inducing laboratory spawning of sea lampreys  

USGS Publications Warehouse

We describe a water-recirculating system for inducing spawning of sea lampreys (Petromyzon marinus) held under laboratory conditions. Water temperature in the system was gradually increased to and maintained at 18 +/- 2 degrees C, the optimal temperature for spawning. About 10% freshwater was added daily to prevent buildup of waste products. Sea lampreys were provided substrate (approximately 3-6 cm in diameter) to build nests, and a water velocity of 0.2-0.3 m/s was maintained with an electric trolling motor. Sea lampreys held in this system exhibited characteristic spawning behavior. Prolarvae produced from artificial fertilization of gametes developed according to the standard timeline.

Fredricks, Kim T.; Seelye, James G.

1995-01-01

8

Exhaust gas recirculation system  

Microsoft Academic Search

An engine exhaust gas recirculation (EGR) system is provided in which a sonic flow EGR valve is moved to open positions to establish a different constant rate of flow at each open position of the EGR valve in response to air pressure acting on a servo means secured to the valve, the air pressure force being controlled by changes in

Rachedi

1983-01-01

9

The effects of ozone and water exchange rates on water quality and rainbow trout Oncorhynchus mykiss performance in replicated water recirculating systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

Rainbow trout Oncorhynchus mykiss performance and water quality were evaluated and compared within six replicated 9.5 cubic meter water recirculating aquaculture systems (WRAS) operated with and without ozone at various water exchange rates. Three separate studies were conducted: 1) low water exchan...

10

Principles of Water Recirculation and Filtration in Aquaculture 1  

E-print Network

designs for recirculating systems and most will work effectively if they accomplish: 1) aeration, 2FA12 Principles of Water Recirculation and Filtration in Aquaculture 1 Michael McGee and Charles/Institute of Food and Agricultural Sciences/University of Florida/Christine Taylor Waddill, Dean. Recirculating

Watson, Craig A.

11

Exhaust gas recirculation system  

SciTech Connect

An engine exhaust gas recirculation (EGR) system is provided in which a sonic flow EGR valve is moved to open positions to establish a different constant rate of flow at each open position of the EGR valve in response to air pressure acting on a servo means secured to the valve, the air pressure force being controlled by changes in a control vacuum opposing the air pressure force and modified by an air bleed device as a function of changes in engine exhaust gas backpressure levels, to provide an EGR valve movement that varies essentially in proportion to changes in engine air flow.

Rachedi, S.H.

1983-08-30

12

Fish Health Management Considerations in Recirculating Aquaculture Systems -Part 1  

E-print Network

Cir 120 Fish Health Management Considerations in Recirculating Aquaculture Systems - Part 1, Tropical Aquaculture Laboratory, Ruskin FL 33570, Program in Fisheries and Aquatic Sciences, School Cooperating. Nick T. Place , Dean Introduction Recirculating aquaculture systems, also known as water reuse

Watson, Craig A.

13

Disinfection of water in recirculating aquaculture systems with peracetic acid (PAA)  

Technology Transfer Automated Retrieval System (TEKTRAN)

The disinfection behaviour of peracetic acid (PAA) in recirculating aquaculture systems (RAS) was investigated. Peracetic acid is a strong oxidizing agent found in various concentrations in different products. Three Wofasteril PAA products (E400 (c), Lspecical; AC 150) were tested in vitro for the...

14

Microbial and physicochemical parameters associated with Legionella contamination in hot water recirculation systems.  

PubMed

Hot water recirculation systems (HWRS) in hotels and nursing homes, which are common in countries such as Spain, have been related to outbreaks of legionellosis. To establish the relationships of microbial and physicochemical parameters, especially protozoa, with the occurrence of Legionella in HWRS, 231 samples from hotels and nursing homes were analysed for Legionella, protozoa, heterotrophic plate counts (HPC) at 22 and 37 °C, Pseudomonas, metals, temperature and others. Legionella pneumophila was the dominant species isolated, and 22 % were sg. 1. The sampling method became particularly important in order to define which factors were involved on the occurrence of Legionella. Results showed that the bacteria and the accompanying microbiota were more abundant in the first flush water whose temperature was lower. The bacteria occurred in those samples with high HPC and were inversely correlated with high temperatures. Multivariate regression showed that a concentration above 1 × 10(5) CFU/100 mL of HPC at 37 °C, Fe above 0.095 ppm and the presence of protozoa increased significantly the risk of Legionella colonization, while univariant regression showed that the presence of Cu above 0.76 ppm and temperature above 55 °C diminished it. Therefore, to reduce the risk associated with Legionella occurrence in HWRS these parameters should be taken into consideration. PMID:23436060

Serrano-Suárez, Alejandra; Dellundé, Jordi; Salvadó, Humbert; Cervero-Aragó, Sílvia; Méndez, Javier; Canals, Oriol; Blanco, Silvia; Arcas, Antoni; Araujo, Rosa

2013-08-01

15

Is growth retardation present in Nile tilapia Oreochromis niloticus cultured in low water exchange recirculating aquaculture systems?  

Microsoft Academic Search

It has been suggested that fish cultured in recirculating aquaculture systems (RAS) grow less as compared with fish cultured in flow-through systems due to the accumulation of substances. In the Netherlands, the commercial culture of Nile tilapia Oreochromis niloticus in 300 and 600MT's systems is done exclusively in RAS operated at water exchange rates as low as 30L\\/kg feed\\/day due

Catarina I. M. Martins; Daniel Ochola; Stephan S. W. Ende; Ep H. Eding; Johan A. J. Verreth

2009-01-01

16

Combustion-gas recirculation system  

DOEpatents

A combustion-gas recirculation system has a mixing chamber with a mixing-chamber inlet and a mixing-chamber outlet. The combustion-gas recirculation system may further include a duct connected to the mixing-chamber inlet. Additionally, the combustion-gas recirculation system may include an open inlet channel with a solid outer wall. The open inlet channel may extend into the mixing chamber such that an end of the open inlet channel is disposed between the mixing-chamber inlet and the mixing-chamber outlet. Furthermore, air within the open inlet channel may be at a pressure near or below atmospheric pressure.

Baldwin, Darryl Dean (Lacon, IL)

2007-10-09

17

Effect of flow rate on water quality parameters and plant growth of water spinach (Ipomoea aquatica) in an aquaponic recirculating system  

Microsoft Academic Search

Recirculating aquaculture–hydroponic systems were designed to provide an artificial, controlled environment that optimizes the growth of fish (or other aquatic species) and soil-less plants, complete control of water quality, the production schedule and the fish product, while conserving water resources. Nutrients removal such as inorganic nitrogen and phosphate is essential for aquaculture wastewater treatment to protect receiving waters from eutrophication

Azizah Endut; Ahmad Jusoh; Nora’aini Ali; W. N. S. Wan Nik; Anuar Hassan

2009-01-01

18

Water Treatment and Performance Characteristics Evaluation of a Pilot-Scale Recirculating Aquaculture System  

Microsoft Academic Search

To minimize the impact on the environment and land requirements, a pilot-scale recirculating aquaculture system was engineered and investigated in a greenhouse. The system included a three-step particulates separation device, fluidized bed reactors (FBR), UV treatment and cooling. Japanese flounder (Paralichthys olivaceus) were raised from initial mean weight 4.9 plusmn 0.6g to final mean weight 35.8 plusmn 14.6g after 140

Yan Zaisheng; Liu Changfa; Wang Shihe; He Jie; Liu Yuan; Zhang Liyong; Zhang Junxin

2008-01-01

19

Observations on side-swimming rainbow trout in water recirculation aquaculture systems.  

PubMed

During a controlled 6-month study using six replicated water recirculation aquaculture systems (WRASs), it was observed that Rainbow Trout Oncorhynchus mykiss in all WRASs exhibited a higher-than-normal prevalence of side swimming (i.e., controlled, forward swimming but with misaligned orientation such that the fish's sagittal axis is approximately parallel to the horizontal plane). To further our understanding of this abnormality, a substudy was conducted wherein side swimmers and normally swimming fish were selectively sampled from each WRAS and growth performance (length, weight), processing attributes (fillet yield, visceral index, ventrum [i.e., thickness of the ventral "belly flap"] index), blood gas and chemistry parameters, and swim bladder morphology and positioning were compared. Side swimmers were found to be significantly smaller in length and weight and had less fillet yield but higher ventrum indices. Whole-blood analyses demonstrated that, among other things, side swimmers had significantly lower whole-blood pH and higher Pco2. Side swimmers typically exhibited swim bladder malformations, although the positive predictive value of this subjective assessment was only 73%. Overall, this study found several anatomical and physiological differences between side-swimming and normally swimming Rainbow Trout. Given the reduced weight and fillet yield of market-age side swimmers, producers would benefit from additional research to reduce side-swimming prevalence in their fish stocks. PMID:25250476

Good, Christopher; Davidson, John; Kinman, Christin; Kenney, P Brett; Bæverfjord, Grete; Summerfelt, Steven

2014-12-01

20

Observations on Side-Swimming Rainbow Trout in Water Recirculation Aquaculture Systems  

PubMed Central

Abstract During a controlled 6-month study using six replicated water recirculation aquaculture systems (WRASs), it was observed that Rainbow Trout Oncorhynchus mykiss in all WRASs exhibited a higher-than-normal prevalence of side swimming (i.e., controlled, forward swimming but with misaligned orientation such that the fish's sagittal axis is approximately parallel to the horizontal plane). To further our understanding of this abnormality, a substudy was conducted wherein side swimmers and normally swimming fish were selectively sampled from each WRAS and growth performance (length, weight), processing attributes (fillet yield, visceral index, ventrum [i.e., thickness of the ventral “belly flap”] index), blood gas and chemistry parameters, and swim bladder morphology and positioning were compared. Side swimmers were found to be significantly smaller in length and weight and had less fillet yield but higher ventrum indices. Whole-blood analyses demonstrated that, among other things, side swimmers had significantly lower whole-blood pH and higher Pco 2. Side swimmers typically exhibited swim bladder malformations, although the positive predictive value of this subjective assessment was only 73%. Overall, this study found several anatomical and physiological differences between side-swimming and normally swimming Rainbow Trout. Given the reduced weight and fillet yield of market-age side swimmers, producers would benefit from additional research to reduce side-swimming prevalence in their fish stocks. Received March 20, 2014; accepted May 20, 2014 PMID:25250476

Good, Christopher; Davidson, John; Kinman, Christin; Kenney, P. Brett; Bæverfjord, Grete; Summerfelt, Steven

2014-01-01

21

Evaluation of air-lift pump capabilities for water delivery, aeration, and degasification for application to recirculating aquaculture systems  

Microsoft Academic Search

A methodology is demonstrated for evaluating the feasibility of using air-lift pumps for water movement, aeration, and degasification in a recirculating aquaculture system. A set of empirical equations are presented modeling the performance of a 5.08-cm (2?) diameter air-lift submerged 91.44 cm (36?) with a 15.24-cm (6?) lift operated at 28–142 l min?1 (1–5 scfm) of air injection. A steady

J. Clay Loyless; Ronald F Malone

1998-01-01

22

A practical application for the chemical treatment of Southern California`s reclaimed, Title 22 water for use as makeup water for recirculating cooling water systems  

SciTech Connect

Pilot cooling water studies conducted at a Southern California landfill/cogeneration station demonstrated a successful chemical treatment program for recirculating cooling water that used unnitrified, reclaimed, Title 22 water as the primary makeup water source. The constituents in the reclaimed water are supplied by variety of residential and waste water sources resulting in a water quality that may vary to a greater degree than domestic water supplies. This water contains high concentrations of orthophosphate, ammonia, chlorides and suspended solids. The impact of which, under cycled conditions is calcium orthophosphate scaling, high corrosion of yellow metal and mild steel, stress cracking of copper alloys and stainless steel and rapidly growing biological activity. A mobile cooling water testing laboratory with two pilot recirculating water systems modeled the cogeneration station`s cooling tower operating conditions and parameters. The tube and shell, tube side cooling heat exchangers were fitted with 443 admiralty, 90/10 copper nickel, 316 stainless steel and 1202 mild steel heat exchanger tubes. Coupons and Corrater electrodes were also installed. A chemical treatment program consisting of 60/40 AA/AMPS copolymer for scale, deposits and dispersion, sodium tolyltriazole for yellow metal corrosion, and a bromination program to control the biological activity was utilized in the pilot systems. Recirculating water orthophosphate concentrations reached levels of 70 mg/L as PO, and ammonia concentrations reached levels of 35 mg/L, as total NH3. The study successfully demonstrated a chemical treatment program to control scale and deposition, minimize admiralty, 90/10 copper nickel and carbon steel corrosion rates, prevent non-heat transfer yellow metal and stainless steel stress cracking, and control the biological activity in this high nutrient water.

Zakrzewski, J. [Calgon Corp., Pittsburgh, PA (United States); Cosulich, J.; Bartling, E. [County Sanitation Districts of Los Angeles County, Whittier, CA (United States)

1998-12-31

23

Evaluation of ozonation on levels of the off-flavor compounds geosmin and 2-methylisoborneol in water and rainbow trout Oncorhynchus mykiss from water recirculation aquaculture systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

Common “off-flavors” in fish cultured in water recirculation aquaculture systems (WRAS) are “earthy” and “musty” due to the presence of the off-flavor metabolites geosmin and 2-methylisoborneol (MIB), respectively. Previously, ozone addition has been applied to WRAS at relatively low doses to break...

24

Hydraulic design of a re-circulating water cooling system of a combined cycle power plant in Thailand  

SciTech Connect

The paper describes the hydraulic design and hydraulic transient analysis of the re-circulating water cooling system of the combined cyclo Sipco power cogeneration plant in Thailand. The power plant of 450 MW total capacity is proposed to be built in two stages. Stage one will produce 300 MW of power and will consist of two gas turbine generators (GTG) and one steam turbine generator (STG). Stage two will produce 150 MW of power and will consist of one GTG and one STG. The cooling system will consist of one GTG and one STG. The cooling system will consist of cooling towers, a combined collecting basin and pump intake sump, pumps and motors, and separate conveyance systems and condensers for the generator units in the two stages. In a re-circulating water cooling system, cold water is pumped from the pump intake sump to the condensers through the conveyance system and hot water from the condensers is carried through the returning pipeline system to the cooling towers, whence the water after cooling is drained into the sump at the base of the towers. Total cooling water requirement for the system in stage one is estimated to be 112,000 gallons per minute (GPM), and that in stage two, 56,000 GPM. The sump is designed using the computer program HEC-2, developed by the US Army Corps of Engineers (COE) and the pump intake basin, following the recommendations of the Hydraulic Institute. The pumps were sized by computing the head loss in the system, and, the steady state and transient performances (during pump start-up and shut-down procedures and due to possible power or mechanical failure of one or all pumps) of the system were analyzed by mathematically modeling the system using the computer program WHAMO (Water Hammer nd Mass Oscillations), also developed by the COE.

Sarkar, C.K.; Pandit, D.R. [Parsons Infrastructure and Technology Group, Boston, MA (United States); Kwon, S.G. [Kolon Engineering and Construction Co., Ltd., Seoul (Korea, Republic of)

1998-12-31

25

In-tank aeration, a necessary compliment of loaded systems in an airlift recirculating aquaculture system  

Technology Transfer Automated Retrieval System (TEKTRAN)

Water treatment components in recirculating aquaculture systems in generally address solids removal, nitrification, circulation, aeration, and degasification. Airlift pumps in a recirculating aquaculture system can address water circulation, aeration, and degasification. Recent data indicates oxygen...

26

Future of recirculating systems in the US aquaculture industry  

Microsoft Academic Search

Recirculating systems consist of a culture unit, a recirculating pump, and a treatment block which facilitate extended re-use of water in the rearing of aquatic animals. As water re-use is extended from a few hours to months or even years, the complexity of the treatment block increases. Classified as either `open` with greater than 10 percent water replacement per day

Malone

1994-01-01

27

Multistage exhaust gas recirculation system  

Microsoft Academic Search

An automotive type exhaust gas recirculation (EGR) system has two modes of operation, a first one that regulates EGR flow at a constant percentage rate as a function of throttle valve position independently of exhaust gas backpressure changes, and a second one that provides a variable percentage rate of flow of EGR gases in response to changes in exhaust gas

D. C. Ahrns; S. H. Rachedi

1983-01-01

28

A nitrogen budget for a closed, recirculating mariculture system  

Microsoft Academic Search

Nitrogen dynamics were evaluated in a closed, recirculating mariculture system by constructing a mass and isotopic balance of all major nitrogen pools. The experimental system consisted of 12?238-l, closed, independent, recirculating systems, each containing red drum (Sciaenopsocellatus), a biological filter, water pump and subsurface aeration. The standard system used in our laboratory was compared to two treatments in order to

Eric S. Thoman; Ellery D. Ingall; D. Allen Davis; Connie R. Arnold

2001-01-01

29

Particle size distribution and removal efficiency for three types of clarifiers in a warm-water, low-salinity, recirculating aquaculture system for juvenile red drum culture  

Technology Transfer Automated Retrieval System (TEKTRAN)

Recirculating aquaculture systems offer a solution to declining natural finfish stocks while limiting nutrient outputs and eutrophication of effluent waters. Because water is reused in these systems, the solids must be efficiently removed by mechanical treatment devices otherwise the solids buildup...

30

Operation of a Water Recirculating Greenwater System for the Semi-Intensive Culture of Mixed-Sex and All-Male Nile Tilapia, Oreochromis niloticus  

Microsoft Academic Search

Recirculating greenwater aquaculture technology is an appropriate method for producing commercial quantities of tilapia in locations that have water scarcity. Greenwater systems achieve three major goals; higher fish production, maximum water recycling (> 98%) and nutrient utilization. Some nutrients are recycled back in this system to sustain the development of photosynthetic algae and nitrifying bacteria creating a “suspended growth treatment

Yousef S. Al-Hafedh; Aftab Alam

2005-01-01

31

Biological Treatment in Recirculating Aquaculture Systems1 William J. Golz  

E-print Network

Biological Treatment in Recirculating Aquaculture Systems1 William J. Golz Department of Civil. 1995. Biological Treatment in Recirculating Aquaculture Systems. In Recirculating aquaculture Treatment in Recirculating Aquaculture Systems 2 Heterotrophs grow very efficiently, doubling in population

32

Fundamental Aspects of Ozone Chemistry in Recirculating Cooling Water Systems — Data Evaluation Needs  

Microsoft Academic Search

Proposed uses of ozone for stand-alone cooling water treatment raise critical questions as to what happens chemically. These questions are of more significance to industrial cooling water systems, which typically have higher temperatures and cooling ranges than do comfort cooling systems. When applying ozone to cooling waters, it is very important for the user to understand many fundamental aspects of

Rip G. Rice; J. Fred Wilkes

1992-01-01

33

A low energy, bio-secure, 'hybrid' recirculation system incorporating air lift pumps for water circulation, aeration, and CO2 degassing  

Technology Transfer Automated Retrieval System (TEKTRAN)

A ‘Hybrid’ recirculating aquaculture system design utilizes elements of both a ‘Centralized’ design concept with a single water treatment system for a number of fish tanks and the ‘Modular’ design concept which employs a individual treatment system for each fish culture tank. The ‘Hybrid’ recirculat...

34

Preoperational test report, recirculation condenser cooling systems  

SciTech Connect

This represents a preoperational test report for Recirculation Condenser Systems, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The four system provide condenser cooling water for vapor space cooling of tanks AY1O1, AY102, AZ1O1, AZ102. Each system consists of a valved piping loop, a pair of redundant recirculation pumps, a closed-loop evaporative cooling tower, and supporting instrumentation; equipment is located outside the farm on concrete slabs. Piping is routed to the each ventilation condenser inside the farm via below-grade concrete trenches. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System.

Clifton, F.T.

1997-11-04

35

Effects of elevated atmospheric carbon dioxide concentrations on water and acid requirements of soybeans grown in a recirculating hydroponic system  

NASA Technical Reports Server (NTRS)

Establishing mass budgets of various crop needs, i.e. water and nutrients, in different environments is essential for the Controlled Ecological Life Support System (CELSS). The effects of CO2 (500 and 1000 umol mol (exp -1)) on water and acid use (for pH control) by soybeans in a recirculating hydroponic system were examined. Plants of cvs. McCall and Pixie were grown for 90 days using the nutrient film technique (NFT) and a nitrate based nutrient solution. System acid use for both CO2 levels peaked near 4 weeks during a phase of rapid vegetative growth, but acid use decreased more rapidly under 500 compared to 1000 umol mol (exp GR) CO2. Total system water use by 500 and 1000 umol mol (exp -1) plants was similar, leaving off at 5 weeks and declining as plants senesced (ca. 9 weeks). However, single leaf transpiration rates were consistently lower at 1000 umol mol (exp -1). The data suggest that high CO2 concentrations increase system acid (and nutrient) use because of increased vegetative growth, which in turn negates the benefit of reduced water use (lower transpiration rates) per unit leaf area.

Mackowiak, C. L.; Wheeler, R. M.; Lowery, W.; Sager, J. C.

1990-01-01

36

In-tank recirculating arsenic treatment system  

DOEpatents

A low-cost, water treatment system and method for reducing arsenic contamination in small community water storage tanks. Arsenic is removed by using a submersible pump, sitting at the bottom of the tank, which continuously recirculates (at a low flow rate) arsenic-contaminated water through an attached and enclosed filter bed containing arsenic-sorbing media. The pump and treatment column can be either placed inside the tank (In-Tank) by manually-lowering through an access hole, or attached to the outside of the tank (Out-of-Tank), for easy replacement of the sorption media.

Brady, Patrick V. (Albuquerque, NM); Dwyer, Brian P. (Albuquerque, NM); Krumhansl, James L. (Albuquerque, NM); Chwirka, Joseph D. (Tijeras, NM)

2009-04-07

37

Use of Produced Water in Recirculated Cooling Systems at Power Generating Facilities  

SciTech Connect

Tree ring studies indicate that, for the greater part of the last three decades, New Mexico has been relatively 'wet' compared to the long-term historical norm. However, during the last several years, New Mexico has experienced a severe drought. Some researchers are predicting a return of very dry weather over the next 30 to 40 years. Concern over the drought has spurred interest in evaluating the use of otherwise unusable saline waters to supplement current fresh water supplies for power plant operation and cooling and other uses. The U.S. Department of Energy's National Energy Technology Laboratory sponsored three related assessments of water supplies in the San Juan Basin area of the four-corner intersection of Utah, Colorado, Arizona, and New Mexico. These were (1) an assessment of using water produced with oil and gas as a supplemental supply for the San Juan Generating Station (SJGS); (2) a field evaluation of the wet-surface air cooling (WSAC) system at SJGS; and (3) the development of a ZeroNet systems analysis module and an application of the Watershed Risk Management Framework (WARMF) to evaluate a range of water shortage management plans. The study of the possible use of produced water at SJGS showed that produce water must be treated to justify its use in any reasonable quantity at SJGS. The study identified produced water volume and quality, the infrastructure needed to deliver it to SJGS, treatment requirements, and delivery and treatment economics. A number of produced water treatment alternatives that use off-the-shelf technology were evaluated along with the equipment needed for water treatment at SJGS. Wet surface air-cooling (WSAC) technology was tested at the San Juan Generating Station (SJGS) to determine its capacity to cool power plant circulating water using degraded water. WSAC is a commercial cooling technology and has been used for many years to cool and/or condense process fluids. The purpose of the pilot test was to determine if WSAC technology could cool process water at cycles of concentration considered highly scale forming for mechanical draft cooling towers. At the completion of testing, there was no visible scale on the heat transfer surfaces and cooling was sustained throughout the test period. The application of the WARMF decision framework to the San Juan Basis showed that drought and increased temperature impact water availability for all sectors (agriculture, energy, municipal, industry) and lead to critical shortages. WARMF-ZeroNet, as part of the integrated ZeroNet decision support system, offers stakeholders an integrated approach to long-term water management that balances competing needs of existing water users and economic growth under the constraints of limited supply and potential climate change.

C. McGowin; M. DiFilippo; L. Weintraub

2006-06-30

38

Effect of copper on the growth of shrimps Litopenaeus vannamei: water parameters and copper budget in a recirculating system  

NASA Astrophysics Data System (ADS)

Shrimps ( Litopenaeus vannamei) were intensively cultured in a recirculating aquaculture system for 98 days to investigate effects of 0.3 mg/L Cu on its performance, Cu budget, and Cu distribution. Shrimps in Cu-treated systems had greater mean final weight (11.10 vs 10.50 g), body length (107.23 vs 106.42 mm), survival rate (67.80% vs 66.40%), and yield (6.42 vs 5.99 kg/m3), and lower feed conversion ratio (1.20 vs 1.29) than those in control systems but the differences were not significant. Vibrio numbers remained stable (104-106 colony forming units/mL) in the rearing tanks of both control and treated systems. Total ammonium-N, nitrite-N, nitrate-N, pH, chemical oxygen demand, 5-day carbonaceous biochemical oxygen demand, and total suspended solids were similar in controls and treatments. Dissolved Cu concentration in the treated systems decreased from 0.284 to 0.089 mg/L while in the control systems it increased from 0.006 2 to 0.018 mg/L. The main sources of Cu in the treated systems were the artificially added component (75.7% of total input), shrimp feed (21.0%), water (2.06%), and shrimp biomass (1.22%). The major outputs of Cu occurred via the mechanical filter (41.7%), water renewal (15.6%), and draining of the sediment trap (15.1%). The foam fractionator removed only 0.69% of total Cu input. Harvested shrimp biomass accounted for 11.68% of Cu input. The Cu concentration of shrimps in the Cu-treated systems (30.70 mg/kg wet weight) was significantly higher than that in control systems (22.02 mg/kg). Both were below the maximum permissible concentration (50 mg/kg) for Cu in seafood for human consumption in China. Therefore, recirculating systems can be used for commercial on-growing of Litopenaeus vannamei without loss of shrimp quality, even in water polluted by 0.30 mg/L Cu. The mechanical filter is the main route for Cu removal.

Cheng, Bo; Liu, Ying; Yang, Hongsheng; Song, Yi; Li, Xian

2014-09-01

39

Use of Produced Water in Recirculating Cooling Systems at Power Generating Facilities  

SciTech Connect

The purpose of this study is to evaluate produced water as a supplemental source of water for the San Juan Generating Station (SJGS). This study incorporates elements that identify produced water volume and quality, infrastructure to deliver it to SJGS, treatment requirements to use it at the plant, delivery and treatment economics, etc. SJGS, which is operated by Public Service of New Mexico (PNM) is located about 15 miles northwest of Farmington, New Mexico. It has four units with a total generating capacity of about 1,800 MW. The plant uses 22,400 acre-feet of water per year from the San Juan River with most of its demand resulting from cooling tower make-up. The plant is a zero liquid discharge facility and, as such, is well practiced in efficient water use and reuse. For the past few years, New Mexico has been suffering from a severe drought. Climate researchers are predicting the return of very dry weather over the next 30 to 40 years. Concern over the drought has spurred interest in evaluating the use of otherwise unusable saline waters. This deliverable describes possible test configurations for produced water demonstration projects at SJGS. The ability to host demonstration projects would enable the testing and advancement of promising produced water treatment technologies. Testing is described for two scenarios: Scenario 1--PNM builds a produced water treatment system at SJGS and incorporates planned and future demonstration projects into the design of the system. Scenario 2--PNM forestalls or decides not to install a produced water treatment system and would either conduct limited testing at SJGS (produced water would have to be delivered by tanker trucked) or at a salt water disposal facility (SWD). Each scenario would accommodate demonstration projects differently and these differences are discussed in this deliverable. PNM will host a demonstration test of water-conserving cooling technology--Wet Surface Air Cooling (WSAC) using cooling tower blowdown from the existing SJGS Unit 3 tower--during the summer months of 2005. If successful, there may be follow-on testing using produced water. WSAC is discussed in this deliverable. Recall that Deliverable 4, Emerging Technology Testing, describes the pilot testing conducted at a salt water disposal facility (SWD) by the CeraMem Corporation. This filtration technology could be a candidate for future demonstration testing and is also discussed in this deliverable.

Kent Zammit; Michael N. DiFilippo

2005-07-01

40

The effects of carbon dioxide on performance and histopathology of rainbow trout Oncorhynchus mykiss in water recirculation aquaculture systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

Chronic exposure to elevated levels of dissolved carbon dioxide (CO2) has been linked to reduced growth, physiological disturbances and negative health outcomes in intensively reared fish. Although pumping to a degassing tower can lower concentrations of dissolved CO2 in water recirculation aquacult...

41

Future of recirculating systems in the US aquaculture industry  

SciTech Connect

Recirculating systems consist of a culture unit, a recirculating pump, and a treatment block which facilitate extended re-use of water in the rearing of aquatic animals. As water re-use is extended from a few hours to months or even years, the complexity of the treatment block increases. Classified as either `open` with greater than 10 percent water replacement per day or `closed` with less than 10 percent daily replacement, most recirculating systems include aerators, clarifiers, and biofilters as key core elements. The aquaculture industry is increasingly facing a variety of socio-economic issues which will dramatically influence its future development. These problems range from increased competition for water rights through price depression and foreign imports to predation by protected migratory birds. As water-use, environmental, and conservation conflicts grow, the cost differences between the flow-through and closed production technologies will narrow, increasing the industry`s use of recirculating systems.

Malone, R.F.

1994-08-01

42

Flavobacterium branchiophilum and F. succinicans associated with bacterial gill disease in rainbow trout Oncorhynchus mykiss (Walbaum) in water recirculation aquaculture systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

Raised rainbow trout Oncorhynchus mykiss in six replicated water recirculation aquaculture systems (WRAS), and manipulated environmental conditions to promote bacterial gill disease (BGD). For each episode of BGD, gill tissue was sampling from affected fish, unaffected fish within the same WRAS, and...

43

Comparing the effects of high vs. low nitrate on the health, performance, and welfare of juvenile rainbow trout Oncorhynchus mykiss within water recirculating aquaculture systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

Previous research indicates that rainbow trout (Oncorhynchus mykiss) begin to exhibit health and welfare problems when cultured within water recirculating aquaculture systems (WRAS) operated at low exchange (6.7 days hydraulic retention time) and a mean feed loading rate of 4.1 kg feed/m3 daily make...

44

Low-head saltwater recirculating aquaculture systems utilized for juvenile red drum production  

Technology Transfer Automated Retrieval System (TEKTRAN)

Recirculating aquaculture systems reuse water with mechanical and biological treatment between each use and thus require wastewater treatment techniques for continuous waste removal. However, the traditional techniques and equipment utilized in recirculating aquaculture systems are expensive. The d...

45

Water treatment and waste characterization evaluation of an intensive recirculating fish production system  

Microsoft Academic Search

A combination of two different technologies used for fish production was evaluated at the North Carolina State University (NCSU) F?ish Barn facility. The combined system included the ECOFISH? tank, developed at the Norwegian Hydrotechnical Laboratory (NHL) at SINTEF (Trondheim, Norway) and water treatment and recycle technology designed at NCSU. Approximately 2170 fingerling tilapia (Oreochromis niloticus, Oreochromis niloticus × Oreochromis aureus)

Joanna G. Twarowska; Philip W. Westerman; Thomas M. Losordo

1997-01-01

46

Processes to improve energy efficiency during pumping and aeration of recirculating water in circular tank systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

Conventional gas transfer technologies for aquaculture systems occupy a large amount of space, require considerable capital investment, and can contribute to high electricity demand. In addition, diffused aeration in a circular tank can interfere with the hydrodynamics of water rotation and the spee...

47

Denitrification in recirculating systems: Theory and applications  

Microsoft Academic Search

Profitability of recirculating systems depends in part on the ability to manage nutrient wastes. Nitrogenous wastes in these systems can be eliminated through nitrifying and denitrifying biofilters. While nitrifying filters are incorporated in most recirculating systems according to well-established protocols, denitrifying filters are still under development. By means of denitrification, oxidized inorganic nitrogen compounds, such as nitrite and nitrate are

Jaap van Rijn; Yossi Tal; Harold J. Schreier

2006-01-01

48

Water and Energy Savings using Demand Hot Water Recirculating Systems in Residential Homes: A Case Study of Five Homes in Palo Alto, California  

SciTech Connect

This report summarizes a preliminary study aimed at estimating the potential of saving potable water, (and the electrical energy used to heat it), that is presently lost directly to the drain while occupants wait for hot water to arrive at the faucet (point of use). Data were collected from five single-family homes in Palo Alto, California. Despite the small sample size in this study, the results make a compelling case for retrofitting homes with hot water recirculation systems to eliminate unnecessary wastage of water at the point of use. Technical as well as behavioral and attitudinal changes towards water conservation are necessary for a fulfilling and successful conservation effort. This report focuses on the technical issues, but behavioral issues are also noted, which may be factored into future studies involving local and state governments and utility companies.

Ally, M.R.

2002-11-14

49

USE OF PRODUCED WATER IN RECIRCULATING COOLING SYSTEMS AT POWER GENERATING FACILITIES  

SciTech Connect

The purpose of this study is to evaluate produced water as a supplemental source of water for the San Juan Generating Station (SJGS). This study incorporates elements that identify produced water volume and quality, infrastructure to deliver it to SJGS, treatment requirements to use it at the plant, delivery and treatment economics, etc. SJGS, which is operated by Public Service of New Mexico (PNM) is located about 15 miles northwest of Farmington, New Mexico. It has four units with a total generating capacity of about 1,800 MW. The plant uses 22,400 acre-feet of water per year from the San Juan River with most of its demand resulting from cooling tower make-up. The plant is a zero liquid discharge facility and, as such, is well practiced in efficient water use and reuse. For the past few years, New Mexico has been suffering from a severe drought. Climate researchers are predicting the return of very dry weather over the next 30 to 40 years. Concern over the drought has spurred interest in evaluating the use of otherwise unusable saline waters. Deliverable 1 presents a general assessment of produced water generation in the San Juan Basin in Four Corners Area of New Mexico. Oil and gas production, produced water handling and disposal, and produced water quantities and chemistry are discussed. Legislative efforts to enable the use of this water at SJGS are also described.

Michael N. DiFilippo

2004-08-01

50

USE OF PRODUCED WATER IN RECIRCULATING COOLING SYSTEMS AT POWER GENERATING FACILITIES  

SciTech Connect

The purpose of this study is to evaluate produced water as a supplemental source of water for the San Juan Generating Station (SJGS). This study incorporates elements that identify produced water volume and quality, infrastructure to deliver it to SJGS, treatment requirements to use it at the plant, delivery and treatment economics, etc. SJGS, which is operated by Public Service of New Mexico (PNM) is located about 15 miles northwest of Farmington, New Mexico. It has four units with a total generating capacity of about 1,800 MW. The plant uses 22,400 acre-feet of water per year from the San Juan River with most of its demand resulting from cooling tower make-up. The plant is a zero liquid discharge facility and, as such, is well practiced in efficient water use and reuse. For the past few years, New Mexico has been suffering from a severe drought. Climate researchers are predicting the return of very dry weather over the next 30 to 40 years. Concern over the drought has spurred interest in evaluating the use of otherwise unusable saline waters. Deliverable 2 focuses on transportation--the largest obstacle to produced water reuse in the San Juan Basin (the Basin). Most of the produced water in the Basin is stored in tanks at the well head and must be transported by truck to salt water disposal (SWD) facilities prior to injection. Produced water transportation requirements from the well head to SJGS and the availability of existing infrastructure to transport the water are discussed in this deliverable.

Michael N. DiFilippo

2004-08-01

51

USE OF PRODUCED WATER IN RECIRCULATING COOLING SYSTEMS AT POWER GENERATING FACILITIES  

SciTech Connect

The purpose of this study is to evaluate produced water as a supplemental source of water for the San Juan Generating Station (SJGS). This study incorporates elements that identify produced water volume and quality, infrastructure to deliver it to SJGS, treatment requirements to use it at the plant, delivery and treatment economics, etc. SJGS, which is operated by Public Service of New Mexico (PNM) is located about 15 miles northwest of Farmington, New Mexico. It has four units with a total generating capacity of about 1,800 MW. The plant uses 22,400 acre-feet of water per year from the San Juan River with most of its demand resulting from cooling tower make-up. The plant is a zero liquid discharge facility and, as such, is well practiced in efficient water use and reuse. For the past few years, New Mexico has been suffering from a severe drought. Climate researchers are predicting the return of very dry weather over the next 30 to 40 years. Concern over the drought has spurred interest in evaluating the use of otherwise unusable saline waters. Produced water is generated nationally as a byproduct of oil and gas production. Seven states generate 90 percent of the produced water in the continental US. About 37 percent of the sources documented in the US Geological Survey's (USGS) Produced Waters Database have a TDS of less than 30,000 mg/l. This is significant because produced water treatment for reuse in power plants was found to be very costly above 30,000 mg/l TDS. For the purposes of this report, produced water treatment was assessed using the technologies evaluated for the San Juan Generating Station (SJGS) in Deliverable 3, Treatment and Disposal Analysis. Also, a methodology was developed to readily estimate capital and operating costs for produced water treatment. Two examples are presented to show how the cost estimating methodology can be used to evaluate the cost of treatment of produced water at power plants close to oil and gas production.

Kent Zammit; Michael N. DiFilippo

2005-01-01

52

Design, loading, and water quality in recirculating systems for low salinity finfish species at the USDA /ARS Sustainable Marine Aquaculture Systems facility (Fort Pierce, FL)  

Technology Transfer Automated Retrieval System (TEKTRAN)

The USDA ARS Sustainable Marine Aquaculture System Facility was established by the USDA ARS in collaboration with Harbor Branch Oceanographic Institute / Florida Atlantic University to improve the efficiency and sustainability of inland warmwater marine fish culture in recirculating aquaculture syst...

53

Exhaust gas recirculation control system for internal combustion engine  

Microsoft Academic Search

An exhaust gas recirculation control system for controlling the amount of exhaust gas subjected to recirculation to the air inlet depending on the amount of inlet air of an internal combustion engine is described. This system comprises a control valve disposed in an exhaust gas recirculation passage, for controlling the amount of exhaust gas recirculation, an orifice disposed in the

T. Ito; T. Nishimiya; S. Numakura; M. Okumura

1980-01-01

54

Closed recirculating system for shrimp-mollusk polyculture  

Microsoft Academic Search

This paper deals with a new system of aquaculture, i.e., a closed recirculating system for shrimp-mollusk polyculture. The\\u000a culture system consisted of several shrimp ponds, a mollusk water-purifying pond and a reservoir. During the production cycle,\\u000a water circulated between the shrimp and mollusk ponds, and the reservoir compensated for water loss from seepage and evaporation.\\u000a Constricted tagelus,Sinonovacula constricta, was selected

Xiongfei Wu; Zhidong Zhao; Deshang Li; Kangmei Chang; Zhuanshang Tong; Liegang Si; Kaichong Xu; Bailin Ge

2005-01-01

55

Developments in recirculation systems for Mediterranean fish species  

Microsoft Academic Search

Nowadays, most European commercial hatcheries use recirculating water systems for all the different stages of Mediterranean fish rearing, from breeders to fingerlings several grams in weight. Despite a higher initial investment relative to flow-through systems, this technology reduces production costs mainly because much less energy is required for heating and the survival rate of the fingerlings is much higher. The

Jean Paul Blancheton

2000-01-01

56

A recirculating seawater aquarium system for inland laboratories  

Microsoft Academic Search

We have designed and installed a 7,500 l recirculating aquarium system for the purpose of maintaining marine gastropods in an inland laboratory. It is completely nonmetallic and can be adapted for any number of isolated living compartments. Vonvenient and efficient filtration is achieved by the use of disposable cartridge filters. The water temperature is regulated by a direct expansion cooling

M. E. Lickey; R. L. Emigh; F. R. Randle

1970-01-01

57

Production of cobia in recirculating systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

Only limited information exists with respect to rearing juvenile cobia Rachycentron canadum to stocker and marketable sizes using recirculating aquaculture systems (RAS). To investigate this topic, two rearing trials were conducted using commercial scale RAS. In Trial 1, juvenile cobia (29 g) we...

58

Fish Health Management Considerations in Recirculating Aquaculture Systems -Part 2: Pathogens1  

E-print Network

Cir 121 Fish Health Management Considerations in Recirculating Aquaculture Systems - Part 2 Aquaculture Laboratory, Ruskin FL 33570, Program in Fisheries and Aquatic Sciences, School of Forest Resources Introduction Recirculating aquaculture systems, also known as water reuse systems, have become more and more

Watson, Craig A.

59

Multi-stage exhaust gas recirculation system  

SciTech Connect

An automotive type exhaust gas recirculation (EGR) system has two modes of operation, a first one that regulates EGR flow at a constant percentage rate as a function of throttle valve position independently of exhaust gas backpressure changes, and a second one that provides a variable percentage rate of flow of EGR gases in response to changes in exhaust gas backpressures, both modes utilizing carburetor ported vacuum modified by an air bleed device as the EGR valve opening force.

Ahrns, D.C.; Rachedi, S.H.

1983-08-16

60

Developments in recirculating systems for Arctic char culture in North America  

Microsoft Academic Search

Arctic char (Salvelinus alpinus) tolerate high-density culture conditions, have an excellent fillet yield, are amenable to niche marketing, and are suitable for production within super-intensive recirculating systems. Much of the North American production of Arctic char has been within recirculating systems, which can provide more optimum water temperatures for fish growth and can also overcome limitations created by a lack

Steven T. Summerfelt; Gary Wilton; David Roberts; Tina Rimmerd; Kari Fonkalsrud

2004-01-01

61

Preoperational test report, recirculation ventilation systems  

SciTech Connect

This represents a preoperational test report for Recirculation Ventilation Systems, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The system provides vapor space cooling of tanks AY1O1, AY102, AZ1O1, AZ102 and supports the ability to exhaust air from each tank. Each system consists of a valved piping loop, a fan, condenser, and moisture separator; equipment is located inside each respective tank farm in its own hardened building. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System.

Clifton, F.T.

1997-11-11

62

The growth of New Guinea impatiens with controlled-release fertilizer in a recirculating subirrigation system  

E-print Network

With concerns increasing over the supply and quality of water, pressure on greenhouse growers to use water and fertilizers more efficiently is also increasing. Controlled-release fertilizers (CRF) and recirculating subordination systems...

Richards, Daphne Ladean

2012-06-07

63

The evaluation of oxygen and carbon dioxide transfer associated with airlifts in recirculating aquaculture systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

Airlifts in recirculating aquaculture systems (RAS) provide aeration, degasification, and water circulation. They allow the simplification of systems, and if designed properly, can reduce the capital costs and minimize operation and maintenance associated with alternative pumping systems. In order t...

64

Comparison of hydroponic crop production techniques in a recirculating fish culture system  

E-print Network

of the experimental recirculating aquaculture system. All major parts are described including the three experimental water treatments. Portion of System Total Water Units Volume (L) Flow (L/day) Retention T trna (hours) Media Surface Ar~a (m ) Aeration...COMPARISON OF HYDROPONIC CROP PRODUCTION TECHNIQUES IN A RECIRCULATING FISH CULTURE SYSTEM A Thesis by STEVEN WHITAKKR WREN Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree...

Wren, Steven Whitaker

2012-06-07

65

Exhaust gas recirculation system for an internal combustion engine  

SciTech Connect

An exhaust gas recirculation system for an internal combustion engine comprises an exhaust driven turbocharger having a low pressure turbine outlet in fluid communication with an exhaust gas conduit. The turbocharger also includes a low pressure compressor intake and a high pressure compressor outlet in communication with an intake air conduit. An exhaust gas recirculation conduit fluidly communicates with the exhaust gas conduit to divert a portion of exhaust gas to a low pressure exhaust gas recirculation branch extending between the exhaust gas recirculation conduit and an engine intake system for delivery of exhaust gas thereto. A high pressure exhaust gas recirculation branch extends between the exhaust gas recirculation conduit and the compressor intake and delivers exhaust gas to the compressor for mixing with a compressed intake charge for delivery to the intake system.

Wu, Ko-Jen

2013-05-21

66

Passive recirculation in the National Launch System's fuel feedlines  

NASA Technical Reports Server (NTRS)

This report contains the passive recirculation tests on the fuel feedline of the National Launch System (NLS). The majority of testing was performed in February 1992, at the National Institute of Standards and Technology in Boulder, CO. The primary objective was to characterize passive recirculation in the NLS fuel feedline. The objective was met by observing the passive recirculation in a one-fifth scale model of the feedline with clear glass sections. The testing was recorded on video tape and with photographs. A description of the testing apparatus and support equipment is included. The experiment indicates that passive recirculation was occurring; higher angles from the horizontal transfer more heat.

Wilson, W. R.; Holt, K. A.

1993-01-01

67

Design and performance characteristics of a low-head recirculating aquaculture tank system for low salinity finfish production  

Technology Transfer Automated Retrieval System (TEKTRAN)

Water treatment components of a recirculating aquaculture system (RAS) consist mainly of: solid removal devices, biofiltration, aeration, degassing units, and water distribution. For each component, multiple options are available and the selection is based on system volume, system hydrodynamics, fis...

68

Dynamics of water and nutrients in closed, recirculating cropping systems in glasshouse horticulture. With special attention to lettuce grown in irrigated sand beds  

Microsoft Academic Search

Due to the high leaching fractions commonly practised in glasshouse horticulture, environmental pollution is clearly a major concern. Switching from soil-based to closed, recirculating substrate-based cropping systems potentially offers a good solution to this problem. As an alternative to the usual trial-and-error method in designing these new systems and optimizing fertigation strategies, this thesis uses the approach of modelling processes

M. Heinen

1997-01-01

69

Distribution of Off-Flavor Compounds and Isolation of Geosmin-Producing Bacteria in a Series of Water Recirculating Systems for Rainbow Trout Culture  

Microsoft Academic Search

Preharvest off-flavor in aquaculture products results in large economic losses to producers due to delayed harvest. The common off flavors “earthy” and “musty” are due to the presence of geosmin and 2-methylisoborneol (MIB), respectively. Although certain species of cyanobacteria are responsible for these problems in pond-cultured fish, the microbial sources of geosmin and MIB in recirculating aquaculture systems (RASs) are

Kevin K. Schrader; Steven T. Summerfelt

2010-01-01

70

The design and construction of an open channel recirculating water tank for the study of biological hydrocarbons  

E-print Network

This project chronicles the design and construction of a small scale recirculating water tank for the purpose of studying biological hydrodynamics. Currently available systems were analyzed and studied prior to developing ...

Hennessey, Thomas V. (Thomas Vincent), III

2005-01-01

71

Performance of a Water Recirculation Loop Maintenance Device and Process for the Advanced Spacesuit Water Membrane Evaporator  

NASA Technical Reports Server (NTRS)

A water loop maintenance device and process to maintain the water quality of the Advanced Spacesuit Water Membrane Evaporation (SWME) water recirculation loop has been undergoing a performance evaluation. The SWME is a heat rejection device under development at the NASA Johnson Space Center to perform thermal control for advanced spacesuits. One advantage to this technology is the potential for a significantly greater degree of tolerance to contamination when compared to the existing Sublimator technology. The driver for the water recirculation maintenance device and process is to further enhance this advantage through the leveraging of fluid loop management lessons-learned from the International Space Station (ISS). A bed design that was developed for a Hamilton Sundstrand military application, and considered for a potential ISS application with the Urine Processor Assembly, provides a low pressure drop means for water maintenance in a recirculation loop. The bed design is coupled with high capacity ion exchange resins, organic adsorbents, and a cyclic methodology developed for the Extravehicular Mobility Unit (EMU) Transport Water loop. The maintenance process further leverages a sorbent developed for ISS that introduces a biocide in a microgravity-compatible manner for the Internal Active Thermal Control System (IATCS). The leveraging of these water maintenance technologies to the SWME recirculation loop is a unique demonstration of applying the valuable lessons learned on the ISS to the next generation of manned spaceflight Environmental Control and Life Support System (ECLSS) hardware. This

Rector, Tony; Steele, John W.; Bue, Grant C.; Campbell, Colin; Makinen, Janice

2012-01-01

72

Design and Evaluation of a Water Recirculation Loop Maintenance Device for the Advanced Spacesuit Water Membrane Evaporator  

NASA Technical Reports Server (NTRS)

A dual-bed device to maintain the water quality of the Advanced Spacesuit Water Membrane Evaporation (SWME) water recirculation loop has been designed and is undergoing testing. The SWME is a heat rejection device under development at the NASA Johnson Space Center to perform thermal control for advanced spacesuits. One advantage to this technology is the potential for a significantly greater degree of tolerance to contamination when compared to the existing sublimator technology. The driver for the development of a water recirculation maintenance device is to further enhance this advantage through the leveraging of fluid loop management lessons learned from the International Space Station (ISS). A bed design that was developed for a Hamilton Sundstrand military application, and considered for a potential ISS application with the Urine Processor Assembly, provides a low pressure drop means for water maintenance in a recirculation loop. The bed design is coupled with high-capacity ion exchange resins, organic adsorbents, and a cyclic methodology developed for the Extravehicular Mobility Unit Transport Water Loop. The bed design further leverages a sorbent developed for the ISS that introduces a biocide in a microgravity-compatible manner for the Internal Active Thermal Control System. The leveraging of these water maintenance technologies to the SWME recirculation loop is a unique demonstration of applying the valuable lessons learned on the ISS to the next generation of crewed spaceflight Environmental Control and Life Support System hardware.

Steele, John W.; Rector, Tony; Bue, Grant C.; Campbell, Colin; Makinen, Janice

2012-01-01

73

Design and Evaluation of a Water Recirculation Loop Maintenance Device for the Advanced Spacesuit Water Membrane Evaporator  

NASA Technical Reports Server (NTRS)

A dual-bed device to maintain the water quality of the Advanced Spacesuit Water Membrane Evaporation (SWME) water recirculation loop has been designed and is undergoing testing. The SWME is a heat rejection device under development at the NASA Johnson Space Center to perform thermal control for advanced spacesuits. One advantage to this technology is the potential for a significantly greater degree of tolerance to contamination when compared to the existing Sublimator technology. The driver for the development of a water recirculation maintenance device is to further enhance this advantage through the leveraging of fluid loop management lessons-learned from the International Space Station (ISS). A bed design that was developed for a Hamilton Sundstrand military application, and considered for a potential ISS application with the Urine Processor Assembly, provides a low pressure drop means for water maintenance in a recirculation loop. The bed design is coupled with high capacity ion exchange resins, organic adsorbents, and a cyclic methodology developed for the Extravehicular Mobility Unit (EMU) Transport Water loop. The bed design further leverages a sorbent developed for ISS that introduces a biocide in a microgravity-compatible manner for the Internal Active Thermal Control System (IATCS). The leveraging of these water maintenance technologies to the SWME recirculation loop is a clear demonstration of applying the valuable lessons learned on the ISS to the next generation of manned spaceflight Environmental Control and Life Support System (ECLSS) hardware.

Steele, John W.; Rector, Tony; Bue, Grant C.; Campbell, Colin; Makinen, Janice

2011-01-01

74

Application of airlift technology in recirculation aquaculture systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

Marine hatcheries implementing recirculating aquaculture technology require pristine water quality and must be designed to provide a disease free environment as much as possible to limit disease transmission. Given the aggressive nature of a variety of marine pathogens, design considerations with re...

75

Closed recirculating system for shrimp-mollusk polyculture  

NASA Astrophysics Data System (ADS)

This paper deals with a new system of aquaculture, i.e., a closed recirculating system for shrimp-mollusk polyculture. The culture system consisted of several shrimp ponds, a mollusk water-purifying pond and a reservoir. During the production cycle, water circulated between the shrimp and mollusk ponds, and the reservoir compensated for water loss from seepage and evaporation. Constricted tagelus, Sinonovacula constricta, was selected as the cultured mollusk, and Pacific white shrimp, Litopenaeus vannamei, as the cultured shrimp. The main managing measures during the production cycle were: setting and using the aerators; introducting the probiotic products timely into the shrimp ponds; adopting a “pen-closing” method for controlling shrimp viral epidemics; setting the flow diversion barriers in the mollusk pond to keep the circulating water flowing through the pond along a sine-like curve and serve as substrate for biofilm; no direct feeding was necessary for the cultured mollusk until the co-cultured shrimp was harvested; natural foods in the water from the shrimp ponds was used for their foods. Two sets of the system were used in the experiment in 2002 and satisfactory results were achieved. The average yield of the shrimp was 11 943.5 kg/hm2, and that of the mollusk was 16 965 kg/hm2. After converting the mollusk yield into shrimp yield at their market price ratio, the food coefficient of the entire system averaged at as low as 0.81. The water quality in the ponds was maintained at a desirable level and no viral epidemics were discovered during the production cycle.

Wu, Xiongfei; Zhao, Zhidong; Li, Deshang; Chang, Kangmei; Tong, Zhuanshang; Si, Liegang; Xu, Kaichong; Ge, Bailin

2005-12-01

76

The accumulation of substances in Recirculating Aquaculture Systems (RAS) affects embryonic and larval development in common carp Cyprinus carpio  

Microsoft Academic Search

The accumulation of substances in Recirculating Aquaculture Systems (RAS) may impair the growth and welfare of fish. To test the severity of contaminants accumulated in RAS, early-life stages of fish were used. Ultrafiltered water from two Recirculating Aquaculture Systems (RAS), one RAS with a high accumulation of substances (water exchange rate 30 L\\/kg feed\\/day) and one RAS with a low accumulation

Catarina I. M. Martins; Marco G. Pistrin; Stephan S. W. Ende; Ep H. Eding; Johan A. J. Verreth

2009-01-01

77

An Inexpensive Recirculating Aquaculture System with Multiple Use Capabilities.  

ERIC Educational Resources Information Center

Describes the construction of an inexpensive recirculating aquaculture system that can hold up to 46 pounds of fish, invertebrates, and mussels for classroom use. The system is versatile, requires little maintenance, and can be used for both teaching and research purposes. (WRM)

Scurlock, Gerald Don, Jr.; Cook, S. Bradford; Scurlock, Carrie Ann

1999-01-01

78

Culture of Penaeus monodon in a recirculating system  

Microsoft Academic Search

In this decade, the production of Penaeus monodon using the traditional open pond method decreased seriously due to disease that spread via seawater. In order to prevent the introduction of pathogenic micro-organisms from seawater, a recirculating system was constructed and tested in this study. This system includes culture tanks (CT), a lamella separator (LS), an aeration tank (AT), a submerged

Kuo-Feng Tseng; Huei-Meei Su; Mao-Sun Su

1998-01-01

79

Researchers evaluate low-energy recirculating system for inland production of marine finfish juveniles  

Technology Transfer Automated Retrieval System (TEKTRAN)

The low-energy recirculating aquaculture system consists of nine separate modules which utilize the double drain fish culture tank paired to a moving bed biofilter. The nine fiberglass tanks are five feet in diameter and normal water depth is about three feet for a total tank volume of approximately...

80

PERFORMANCE CHARACTERISTICS OF THE FLOATING BEAD BIOCLARIFIER IN A RECIRCULATING AQUACULTURE SYSTEM  

Technology Transfer Automated Retrieval System (TEKTRAN)

In a recirculating aquaculture production system an important requirement is an efficient and effective process for water treatment. The objective of this study was to evaluate the nitrification and solids removal performance of a propeller-wash floating media biofilters in a two-tank small-scale ti...

81

Management Ability and the Economics of Recirculating Aquaculture Production Systems  

Microsoft Academic Search

A bioeconomic model of fish growth in recirculating aquaculture systems was constructed by developing a bioenergetic model comprised of metabolic sub-models for growth, ammonia production, and oxygen consumption. Metabolite accumulations are determined by exogenous control variables for filtration and aeration and used to indirectly represent management ability. Numerical solutions to model parameters were obtained using a two point boundary shooting

Richard F. Kazmierczak Jr.; Rex H. Caffey

1995-01-01

82

Aeration Performance of Triangular Notch Weirs at Recirculating System  

Microsoft Academic Search

An adequate supply of dissolved oxygen is essential for the survival of aquatic organisms. Hydraulic structures can increase dissolved oxygen levels by creat- ing turbulent conditions, where small air bubbles are carried into the bulk of the flow. Plunging overfall jets from weirs at recirculating systems are a partic- ular instance of this. This paper seeks triangular notch weirs having

AHMET BAYLAR; TAMER BAGATUR; AHMET TUNA

83

Growth Performance of Walleye, Sander vitreus, in Recirculating Aquaculture Systems  

Microsoft Academic Search

Walleye, Sander vitreus, fingerlings were reared in two recirculating aquaculture systems (RAS) to compare growth performance at three stocking densities (11, 24, and 36 kg\\/m). There was a negative relationship between increasing stocking density and growth calculated as percent body weight (BW) gain\\/day, total length (mm) gain\\/day, specific growth rate (SGR) of weight (%\\/day), and SGR of total length (%\\/day).

Chester B. Zarnoch; Martin P. Schreibman; Richard T. Colesante; Michael B. Timmons

2010-01-01

84

DETERMINATION OF THE SOLIDS REMOVAL EFFICIENCY FOR SYSTEM COMPONENTS IN A RECIRCULATING AQUACULTURE SYSTEM USING PARTICLE SIEVE ANALYSIS  

Technology Transfer Automated Retrieval System (TEKTRAN)

A major target in the recirculating water treatment scheme of an aquaculture production system is removal of suspended solids. The large volumes of waste fish generate are highly organic in nature and contribute to filter clogging, ammonia production, oxygen consumption, and disease for systems empl...

85

Photocatalytic reactors for treating water pollution with solar illumination: A simplified analysis for n-steps flow reactors with recirculation  

Microsoft Academic Search

The concentration of dissolved oxygen in water, in equilibrium with atmospheric air (ca. 8ppm at 20°C), defines the limits of all practical oxidizing processes for removing pollutants in photocatalytic reactors. To solve this limitation, an alternative approach to that of a continuously aerated reactor is the use of a recirculating system with aeration performed after every cycle at the reactor

Gerd Sagawe; Rodolfo J. Brandi; Detlef Bahnemann; Alberto E. Cassano

2005-01-01

86

Soil nitrifying enrichments as biofilter starters in intensive recirculating saline water aquaculture  

E-print Network

aquaculture Abstract Intensive recirculating aquaculture relies on biofilters to sustain satisfactory water quality in the ponds. Establishment of new biofilters in aquaculture ponds without a start-up culture

Gross, Amit

87

Disinfection of Pythium-infested recirculation water by UV-oxidation technology.  

PubMed

Selective disinfection against Pythium aphanidermatum in recirculation water was tested with UV-irradiation and with UV-oxidation technology with the objective to reduce the electrical energy consumption per cubic meter treated water. UV-oxidation technology is based on injection of hydrogen peroxide in recirculation water, just before passage along a UV-lamp, thus creating hydroxyl radicals. Pythium aphanidermatum was applied artificially to recirculation water from tomatoes, grown, in rockwool and coconut fibre. Other parameters in this study were pH and transmission value (T10) of the infested recirculation water. Results indicated that the recommended UV-C dose of 100 mJ/cm2 for elimination of fungal pathogens in general can be lowered in case recirculation water is infected with Pythium aphanidermatum only. When UV-oxidation technology was applied with 1 mmol hydrogen peroxide per litre recirculation water, the UV-C dose could be reduced even more in comparison with merely UV irradiation. PMID:12425022

Runia, W T; Boonstra, S

2001-01-01

88

Recyclotron III, a recirculating plasma fusion system  

SciTech Connect

This patent describes a recyclotron nuclear fusion system comprising recyclotrons. Each recyclotron comprises cyclotron means for receiving and accelerating charged particles in spiral and work conservative pathways. An output means forms a beam from particles received from the cyclotron means; (i) the cyclotron means comprising (a) a channel shaped electromagnet having a pair of indented polefaces, oriented along an input axis and defining an input axis and defining an input magnetic well, (b) a pair of elongated linear electrodes centered along the input magnetic well arranged generally parallel to the input axis and having a gap therebetween, (c) tuned oscillator means connected to the electrodes for applying an oscillating electric potential thereto, (ii) the output means comprising (e) inverter means comprising an electromagnet having a polarity opposite that of the channel shaped electromagnet oriented contigously therealong for extracting fully accelerated particles from the cyclotron means, and (f) reinverter means comprising an electromagnet having a polarity the same as that of the channel shaped electromagnet for correcting the flightpath of the extracted particles.

Jarnagin, W.S.

1987-01-27

89

Growth and Culture of Larval and Juvenile Tautogs in a Closed Recirculating-Seawater System  

Microsoft Academic Search

Field-captured and laboratory-held adult tautogs Tautoga onitis were allowed to spawn naturally under laboratory conditions. Embryos were cultured to hatching and raised successfully through the larval stage to 490-d-old posthatch juveniles. A large (8,500-L), closed, recirculating-seawater system, designed with a biological filter containing air diffusers that passed a strong air?water mixture through a high-surface-area substrate, was used to culture the

Dean M. Perry; Renee Mercaldo-Allen; Stacy Burgh

2001-01-01

90

Evaluation of the impact of nitrate-nitrogen levels in recirculating aquaculture systems on concentrations of the off-flavor compounds geosmin and 2-methylisoborneol in water and rainbow trout (Oncorhynchus mykiss)  

Technology Transfer Automated Retrieval System (TEKTRAN)

Aquatic animals raised in recirculating aquaculture systems (RAS) can develop preharvest “off-flavors” such as “earthy” or “musty” which are caused by the bioaccumulation of the odorous compounds geosmin or 2-methylisoborneol (MIB), respectively, in their flesh. Tainted aquatic products cause large...

91

Inactivation of bacteria using ultraviolet irradiation in a recirculating salmonid culture system  

Technology Transfer Automated Retrieval System (TEKTRAN)

The objective of this research was to determine the ultraviolet (UV) irradiation dosages required to inactivate bacteria in a commercial-scale recirculating salmonid culture system. Research was conducted in the commercial-scale recirculating system used for Arctic char growout at the Conservation ...

92

NITRIFICATION PERFORMANCE OF A PROPELLER-WASHED BEAD CLARIFIER SUPPORTING A FLUIDIZED SAND BIOFILTER IN A RECIRCULATING WARMWATER FISH SYSTEM  

Technology Transfer Automated Retrieval System (TEKTRAN)

A propeller-wash bead filter (PWBF) and a fluidized sand filter (FSF) on a 28 m3 recirculating system stocked with tilapia maintained favorable water quality at five different feed rates, ranging from 0.9 to 4.5 kg feed per day. TAN removal rates ranged up to about 200 g TAN per m3 of media per day ...

93

Handheld recirculation system and customized media for microfluidic cell culture.  

PubMed

A palm-sized microfluidic recirculation system and customized media enable simplified long-term culture and imaging of cells. The combination of bare Braille display modules, a leveled monolithic surface for complete chip mounting, and a transparent heater improved portability, mechanical stability and optical accessibility. Modification of basal culture media with Leibovitz's L-15 medium enabled an incubator-free culture of carbonate-dependent cells by eliminating the need for exogenous carbon dioxide. This capability is demonstrated through time-lapse recording of proliferation of C2C12 myoblasts and MC3T3-E1 osteoblasts for over 2 weeks in ambient atmosphere without medium exchange. The method opens up new possibilities for portable cell culture and for long-term continuous visual monitoring of cells. PMID:16372083

Futai, Nobuyuki; Gu, Wei; Song, Jonathan W; Takayama, Shuichi

2006-01-01

94

EVALUATING THE IMPACT OF WATER CHEMISTRY ON CUPROSOLVENCY AND COPPER CORROSION BY-PRODUCT USING A SIMPLE COPPER PIPE RECIRCULATING LOOP SYSTEM  

EPA Science Inventory

1991, EPA publicized the Lead and Copper Rule (LCR),which set regulations to minimize the amount of lead copper in drinking water. The LCR set the copper action level at 1.3 mg/L in more then 10% of customer?s first-draw taps sampled. Potential health effects of copper include vo...

95

Power plant including an exhaust gas recirculation system for injecting recirculated exhaust gases in the fuel and compressed air of a gas turbine engine  

DOEpatents

A power plant is provided and includes a gas turbine engine having a combustor in which compressed gas and fuel are mixed and combusted, first and second supply lines respectively coupled to the combustor and respectively configured to supply the compressed gas and the fuel to the combustor and an exhaust gas recirculation (EGR) system to re-circulate exhaust gas produced by the gas turbine engine toward the combustor. The EGR system is coupled to the first and second supply lines and configured to combine first and second portions of the re-circulated exhaust gas with the compressed gas and the fuel at the first and second supply lines, respectively.

Anand, Ashok Kumar; Nagarjuna Reddy, Thirumala Reddy; Shaffer, Jason Brian; York, William David

2014-05-13

96

Performance of the prototype gas recirculation system with built-in RGA for INO RPC system  

NASA Astrophysics Data System (ADS)

An open loop gas recovery and recirculation system has been developed for the INO RPC system. The gas mixture coming from RPC exhaust is first desiccated by passing through molecular sieve (3 Å+4 Å). Subsequent scrubbing over basic active alumina removes toxic and acidic contaminants. The Isobutane and Freon are then separated by diffusion and liquefied by fractional condensation by cooling up to -26C. A Residual Gas Analyser (RGA) is being used in the loop to study the performance of the recirculation system. The results of the RGA analysis will be discussed.

Bhuyan, M.; Datar, V. M.; Joshi, A.; Kalmani, S. D.; Mondal, N. K.; Rahman, M. A.; Satyanarayana, B.; Verma, P.

2012-01-01

97

Fish Health Management Considerations in Recirculating Aquaculture systems -Part 3: General  

E-print Network

Cir 122 Fish Health Management Considerations in Recirculating Aquaculture systems -Part 3: General Professor, Tropical Aquaculture Laboratory, Ruskin FL 33570, Department of Fisheries and Aquatic Sciences commonly used in aquaculture facilities, wholesale and retail tropical fish facilities, and public aquaria

Watson, Craig A.

98

TO RATING FIXED-FILM BIOFILTERS USED IN RECIRCULATING AQUACULTURE SYSTEMS  

Technology Transfer Automated Retrieval System (TEKTRAN)

A standardized methodology for evaluating and rating biofilters is proposed to simplify design of recirculating systems. This methodology will allow engineers to compare biofilters options and accurately predict performance before construction. The methodology is based upon an increasing recognized ...

99

Design and installation of a high Reynolds number recirculating water tunnel  

NASA Astrophysics Data System (ADS)

The High-Reynolds Number Fluid Mechanics Laboratory has recently been established at Oklahoma State University (OSU). The three primary components of the laboratory are 1) a recirculating water tunnel, 2) a multiphase pipe flow facility, and 3) a multi-scale flow visualization system. This thesis focuses on the design and fabrication of the water tunnel, which will be used for high-Reynolds number turbulent boundary layer research. Two main design criteria for the water tunnel were to achieve a momentum thickness based Reynolds number in excess of 104 and to have high optical access to the flow surfaces in the test section. This is being achieved with a 1 m. long test section and a maximum flow speed of 10 m/s. This Reynolds number was targeted to bridge the gap between typical university water tunnels (103) and the world's largest water tunnel facilities (105). The water tunnel is powered by a 150 hp motor and a 4500 gpm capacity centrifugal pump. The water tunnel is designed for a maximum operating pressure of 40 psi. This will make the facility a low cost option to perform high-Reynolds number aerodynamic and hydrodynamic tests. Improved flow imaging capability is a major advantage to liquid based fluid facilities because of the increased density for seeding and reduced field-of-view for equivalent Reynolds number. The laboratory's state-of-the-art flow visualization system can be used for time-resolved and phase averaged stereo- particle-image-velocimetry (sPIV), laser-induced-fluorescence, and high-speed imaging. Design provisions are also made to allow a multi-phase loop to share the pump and motor configuration of this water tunnel facility. The major design decisions that went into the design of the water tunnel facility are discussed. The design considerations that were taken into account for the test section, flow conditioning sections and the entire flow loop are discussed in greater detail. The final configuration and the technical drawings of the water tunnel flow loop, the test section, the contraction and diffuser sections are also provided. The installation procedure that will be utilized to install the water tunnel in the High Reynolds Number Fluid Mechanics Laboratory is also discussed.

Daniel, Libin

100

Temporal and spatial pore water pressure distribution surrounding a vertical landfill leachate recirculation well.  

PubMed

Addition of liquids into landfilled waste can result in an increase in pore water pressure, and this in turn may increase concerns with respect to geotechnical stability of the landfilled waste mass. While the impact of vertical well leachate recirculation on landfill pore water pressures has been mathematically modeled, measurements of these systems in operating landfills have not been reported. Pressure readings from vibrating wire piezometers placed in the waste surrounding a liquids addition well at a full-scale operating landfill in Florida were recorded over a 2-year period. Prior to the addition of liquids, measured pore pressures were found to increase with landfill depth, an indication of gas pressure increase and decreasing waste permeability with depth. When liquid addition commenced, piezometers located closer to either the leachate injection well or the landfill surface responded more rapidly to leachate addition relative to those far from the well and those at deeper locations. After liquid addition stopped, measured pore pressures did not immediately drop, but slowly decreased with time. Despite the large pressures present at the bottom of the liquid addition well, much smaller pressures were measured in the surrounding waste. The spatial variation of the pressures recorded in this study suggests that waste permeability is anisotropic and decreases with depth. PMID:21655145

Kadambala, Ravi; Townsend, Timothy G; Jain, Pradeep; Singh, Karamjit

2011-05-01

101

Temporal and Spatial Pore Water Pressure Distribution Surrounding a Vertical Landfill Leachate Recirculation Well  

PubMed Central

Addition of liquids into landfilled waste can result in an increase in pore water pressure, and this in turn may increase concerns with respect to geotechnical stability of the landfilled waste mass. While the impact of vertical well leachate recirculation on landfill pore water pressures has been mathematically modeled, measurements of these systems in operating landfills have not been reported. Pressure readings from vibrating wire piezometers placed in the waste surrounding a liquids addition well at a full-scale operating landfill in Florida were recorded over a 2-year period. Prior to the addition of liquids, measured pore pressures were found to increase with landfill depth, an indication of gas pressure increase and decreasing waste permeability with depth. When liquid addition commenced, piezometers located closer to either the leachate injection well or the landfill surface responded more rapidly to leachate addition relative to those far from the well and those at deeper locations. After liquid addition stopped, measured pore pressures did not immediately drop, but slowly decreased with time. Despite the large pressures present at the bottom of the liquid addition well, much smaller pressures were measured in the surrounding waste. The spatial variation of the pressures recorded in this study suggests that waste permeability is anisotropic and decreases with depth. PMID:21655145

Kadambala, Ravi; Townsend, Timothy G.; Jain, Pradeep; Singh, Karamjit

2011-01-01

102

Culture of selected organisms in recirculating and flow-through systems using thermal effluent  

E-print Network

of. 1~&STER OF SCIENCE August. 1978 Najor Subject: Wildlife and Fisheries Sciences CULTURE OF SELECTED ORGANISMS IN RECIRCULATING AND FLOW-THROUGH SYSTEMS USING THERMAL EFFLUENT A Thesis by TERRI LAYNE BERRY Approved as to style and content... by: (Chairman of Commit ) Head of Department Member Member August, l978 443161 ABSTRACT Culture of Selected Organism. in Recirculating and Flow-Through Systems Using Thermal Effle nt. (August 1978) Terri Layne Berry, B. S. , Texas A...

Berry, Terri Layne

2012-06-07

103

Full-scale demonstration of in situ cometabolic biodegradation of trichloroethylene in groundwater 1. Dynamics of a recirculating well system  

NASA Astrophysics Data System (ADS)

Recirculating well systems provide an engine for the in situ treatment of subsurface contaminants. Although numerous recirculating wells have been installed in the field, for such systems, there is a paucity of comprehensive monitoring data and models constrained to data appearing in the research literature. Here we present an extensive data set combined with detailed inverse and simulation analyses for a two-well groundwater recirculation system used for in situ bioremediation at Edwards Air Force Base in southern California. The ``conveyor belt'' flow system, which was established for in situ treatment of trichloroethylene (TCE) in two bioactive zones, was created by pumping water upward in one well and downward in another well, each well being screened in both the upper and lower aquifers. A bromide tracer test was conducted and extensively monitored for 60 days. Combined inverse analysis was conducted on hydraulic heads from 38 monitoring wells, 32 bromide concentration histories, and a constraint on the degree of recirculation that was based on TCE concentration data. Four different formulations involving alternative weighting schemes used in a nonlinear weighted least squares simulation-regression analysis were explored. The best formulation provided parameter estimates with tight bounds on estimated covariances, suggesting that the model provides a reasonable description of the hydrogeologic system. Our investigation indicates the geometry of the recirculation zone and the degree of recirculation under two different sets of operating conditions. Surprisingly, our analysis suggests that the effects of aquifer heterogeneity are not significant at this site under the conditions of forced recirculation. Furthermore, anomalous flow through an open monitoring well created significant vertical short-circuiting between the generally insulated aquifers. Flow through this small open conduit was equivalent to as much as 33% of the flow through the pumping wells. Using the model as a guide, we treated the aquifer system and bioactive zones as an equivalent mixed reactor to develop simple expressions relating effluent concentrations to influent concentrations. We demonstrate how these expressions are useful in predicting the removal of TCE that had undergone in situ bioremediation in the recirculatory treatment well system. The finite element model developed in this work serves as the foundation for a reactive transport simulator that we developed to analyze bioremediation which occurred during a 444 day experiment [Gandhi et al., 2002].

Gandhi, Rahul K.; Hopkins, Gary D.; Goltz, Mark N.; Gorelick, Steven M.; McCarty, Perry L.

2002-04-01

104

Electron recirculation in electrostatic multicusp systems: II. System performance scaling of one-dimensional rollover wells  

Microsoft Academic Search

In an earlier paper a comprehensive study was made of the recirculation and losses of electrons in their flow through simple inverse power-law potential wells bounded by similarly inverse power-law dependent magnetic fields. This study examined electron flow and loss behavior in the simplest approximation invoked to describe Polywell confinement systems. The importance of this study, and of the present

R. W. Bussard; K. E. King

1992-01-01

105

Low frequency ultrasound and UV-C for elimination of pathogens in recirculating aquaculture systems.  

PubMed

Low frequency ultrasound (LFUS) was evaluated as a novel disinfection technique within recirculating aquaculture systems both individually and combined with UV-C. Dose-dependent inactivation rates were determined for the total viable counts and model organisms representing different taxa of common fish parasites: the ciliate Paramecium sp., second larval stage (L2) of the nematode Anguillicola crassus and metanauplii of Artemia sp. Application of LFUS up to 19 kJ/L did not reduce the number of colony forming units (CFU), whilst UV-C irradiation was highly effective. Pre-treatment with LFUS reduced the mean size of suspended solids in aquaculture water and thus increased the germicidal effect of UV-C by up to 0.6 log units. LFUS was effective against the eukaryotic organisms, and the dose-dependent inactivation could be well described by functions of an exponential decay. However, the efficiency of LFUS differed greatly between species. A LFUS dose of 1.9 kJ/L (consumed energy) was sufficient to inactivate Artemia by 99%, but a ten times higher dose was necessary to inactivate 95% and 81% of Paramecium and Anguillicola larvae, respectively. In clear water, the energetic efficiency of UV-C (emitted by a low pressure lamp) against Paramecium and Anguillicola larvae was higher compared to LFUS, but LFUS was more efficient against Artemia. However, the efficiency of LFUS against ciliates or nematode larvae would be similar or even higher than UV-C in highly turbid water or if less efficient medium pressure lamps are used. This study shows that LFUS can be applied safely at energy densities that are effective against a wide range of parasites like ciliates, nematodes and crustaceans. The combination of LFUS and UV-C could provide an appropriate water treatment with regards to all relevant pathogens in recirculating aquaculture systems. PMID:23434531

Bazyar Lakeh, Amir Abbas; Kloas, Werner; Jung, Rainer; Ariav, Ra'anan; Knopf, Klaus

2013-09-01

106

Performance characteristics of fluidised bed biofilters in a novel laboratory-scale recirculation system for rainbow trout: nitrification rates, oxygen consumption and sludge collection  

Microsoft Academic Search

A laboratory-scale recirculating aquaculture system for fluidised bed biofilter evaluation was engineered. The design included all components found in typical full-scale commercial production systems. The system included two identical units each with oxygenation, UV treatment, cooling, biofiltration and a particulates separation device. Water from the two systems was mixed in a degassing unit. A 1 month test period after biofilter

J Skjølstrup; P. H Nielsen; J.-O Frier; E McLean

1998-01-01

107

Comparison of aerobically-treated and untreated crop residue as a source of recycled nutrients in a recirculating hydroponic system  

Microsoft Academic Search

This study compared the growth of potato plants on nutrients recycled from inedible potato biomass. Plants were grown for 105 days in recirculating, thin-film hydroponic systems containing four separate nutrient solution treatments: 1) modified half-strength Hoagland's (control), 2) liquid effluent from a bioreactor containing inedible potato biomass, 3) filtered (0.2 ?m) effluent, and 4) the water soluble fraction of inedible

C. L. Mackowiak; J. L. Garland; R. F. Strayer; B. W. Finger; R. M. Wheeler

1996-01-01

108

Design of a computerized, temperature-controlled, recirculating aquaria system  

E-print Network

temperature fluctuations up to 10 8C. A LabVIEW program compared the temperature recorded by thermocouples in fish tanks to a desired set temperature and then calculated the amount of hot or cold water to add temperature of the input water and ensured that all fish tanks had the same turnover rate. The system

Bonar, Scott A.

109

Research on the water purification for reclaimed water resource supply-type lakes by the method of recirculation filtration  

Microsoft Academic Search

Based on the result of suitable filter screening9ÿ A recirculation filtration process with multi-medias was applied to investigate the reactor performance in treating reclaimed water resource supply-type lake water. The results showed that the pollutant removal capabilities for single species packing filter was in the following order: activated carbon> composite inorganic medium>volcanic rock>quartz sand>gravel. A pilot scale test has been

Rihong Liao; Yingjie Shen; Nan Zhan; Cao Liu; Yunfang Huang

2011-01-01

110

Intensive mass production of Artemia in a recirculated system  

Microsoft Academic Search

An outdoor closed system for intensive Artemia biomass production was evaluated. The system integrates the use of inexpensive agro-techno products and photosynthesis to create an improved diet for culturing adult Artemia. The diet in the initial days of culture consists of microalgae, followed by a mixture of torula yeast and soy protein. No water or solids are discharged from the

Odi Zmora; Muki Shpigel

2006-01-01

111

Internal dust recirculation system for a fluidized bed heat exchanger  

DOEpatents

A fluidized bed heat exchanger in which air is passed through a bed of particulate material containing fuel disposed in a housing. A steam/water natural circulation system is provided in a heat exchange relation to the bed and includes a steam drum disposed adjacent the bed and a tube bank extending between the steam drum and a water drum. The tube bank is located in the path of the effluent gases exiting from the bed and a baffle system is provided to separate the solid particulate matter from the effluent gases. The particulate matter is collected and injected back into the fluidized bed.

Gamble, Robert L. (Wayne, NJ); Garcia-Mallol, Juan A. (Morristown, NJ)

1981-01-01

112

A recirculating hydroponic system for studying peanut (Arachis hypogaea L.)  

NASA Technical Reports Server (NTRS)

Peanut (Arachis hypogaea L.) plants were grown hydroponically, using continuously recirculating nutrient solution. Two culture tray designs were tested; one tray design used only nutrient solution, while the other used a sphagnum-filled pod development compartment just beneath the cover and above the nutrient solution. Both trays were fitted with slotted covers to allow developing gynophores to reach the root zone. Peanut seed yields averaged 350 gm-2 dry mass, regardless of tray design, suggesting that substrate is not required for hydroponic peanut production.

Mackowiak, C. L.; Wheeler, R. M.; Stutte, G. W.; Yorio, N. C.; Ruffe, L. M.; Sager, J. C. (Principal Investigator)

1998-01-01

113

Demonstration of a Highly Efficient Solid Oxide Fuel Cell Power System Using Adiabatic Steam Reforming and Anode Gas Recirculation  

SciTech Connect

Solid oxide fuel cells (SOFC) are currently being developed for a wide variety of applications because of their high efficiency at multiple power levels. Applications for SOFCs encompass a large range of power levels including 1-2 kW residential combined heat and power applications, 100-250 kW sized systems for distributed generation and grid extension, and MW-scale power plants utilizing coal. This paper reports on the development of a highly efficient, small-scale SOFC power system operating on methane. The system uses adiabatic steam reforming of methane and anode gas recirculation to achieve high net electrical efficiency. The anode exit gas is recirculated and all of the heat and water required for the endothermic reforming reaction are provided by the anode gas emerging from the SOFC stack. Although the single-pass fuel utilization is only about 55%, because of the anode gas recirculation the overall fuel utilization is up to 93%. The demonstrated system achieved gross power output of 1650 to 2150 watts with a maximum net LHV efficiency of 56.7% at 1720 watts. Overall system efficiency could be further improved to over 60% with use of properly sized blowers.

Powell, Michael R.; Meinhardt, Kerry D.; Sprenkle, Vincent L.; Chick, Lawrence A.; Mcvay, Gary L.

2012-05-01

114

Off-flavors in salmonids raised in recirculating aquaculture systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

Producers of aquaculture products will typically verify the flavor quality of their product by sensory evaluation (flavor testing) before harvesting the crop for market. “Off-flavors” detected in the product may require holding the fish in a purging system containing fresh, clean water to depurate ...

115

Applying rotary jet heads for mixing and mass transfer in a forced recirculation tank reactor system  

Microsoft Academic Search

An approximation to an ideally mixed tank reactor can be obtained by vigorous stirring with mechanical mixers. For an aerated reactor the gas dispersion contributes to the mixing process. Mixing can also be achieved by recirculation of a portion of the liquid through either an internal or an external loop.In this study, we determine mixing times in water and CMC

Mikkel Nordkvist; Thomas Grotkjær; Jan S. Hummer; John Villadsen

2003-01-01

116

Prototype recirculating aquaculture system design for juvenile red drum production as part of the Florida Fish and Wildlife Conservation commission’s Hatchery Network Initative  

Technology Transfer Automated Retrieval System (TEKTRAN)

A prototype recirculating aquaculture system for the production of red drum (Sciaenops ocellatus) includes four 10-foot diameter by four foot height tanks for a tank volume of approximately 300 ft3 each (2200 gallons). Water flow for the system is provided for by a low head propeller pump which prov...

117

Oxygen mass balance in a recirculation aquaculture system for raising European Wels (Silurus glanis L.)  

Microsoft Academic Search

The growth of the European Wels or sheat-fish (Silurus glanis L.) was eva- luated in a recirculation aquaculture system situated in a greenhouse. Recir- culation aquaculture system components were evaluated in terms of oxygen use and generation. Oxygen gradients revealed the main fault of the originally constructed system elements - mechanical and biological filters. The influen- ce of organic matter

Viktoras Mongirdas; Albinas Kusta

2006-01-01

118

Growth and survival of larval and juvenile cobia Rachycentron canadum in a recirculating raceway system  

Microsoft Academic Search

Cobia Rachycentron canadum is a fast-growing, pelagic marine species that has recently attracted aquaculturists in both the research and commercial sectors. The typical method of grow-out for this species is in outdoor systems where production is limited to locations and seasons conducive for adequate growth and survival. Expanding the culture of cobia to indoor recirculating aquaculture systems (RAS) would allow

Cynthia K. Faulk; Jeffrey B. Kaiser; G. Joan Holt

2007-01-01

119

PERFORMANCE OF A ROTATING BIOLOGICAL CONTRACTOR IN TILAPIA RECIRCULATING AQUACULTURE SYSTEM  

Technology Transfer Automated Retrieval System (TEKTRAN)

This paper describes the performance characteristics of an industrial-scale air-driven rotating biological contactor (RBC) installed in a recirculating aquaculture system (RAS) rearing tilapia at 28 oC. This 3-staged RBC system was configured with stages 1 and 2 possessing approximately the same to...

120

Fulminant hepatic failure following marijuana drug abuse: Molecular adsorbent recirculation system therapy  

PubMed Central

Marijuana is used for psychoactive and recreational purpose. We report a case of fulminant hepatic failure following marijuana drug abuse who recovered following artificial support systems for acute liver failure. There is no published literature of management of marijuana intoxication with molecular adsorbent recirculation system (MARS). MARS is effective and safe in patients with fulminant hepatic failure following marijuana intoxication. PMID:24049281

Swarnalatha, G.; Pai, S.; Ram, R.; Dakshinamurty, K. V.

2013-01-01

121

Fulminant hepatic failure following marijuana drug abuse: Molecular adsorbent recirculation system therapy.  

PubMed

Marijuana is used for psychoactive and recreational purpose. We report a case of fulminant hepatic failure following marijuana drug abuse who recovered following artificial support systems for acute liver failure. There is no published literature of management of marijuana intoxication with molecular adsorbent recirculation system (MARS). MARS is effective and safe in patients with fulminant hepatic failure following marijuana intoxication. PMID:24049281

Swarnalatha, G; Pai, S; Ram, R; Dakshinamurty, K V

2013-09-01

122

Production characteristics of body composition of Florida pompano reared to market size at two different densities in low salinity recirculating aquaculture systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

The effect of culture density on production characteristics and body composition of Florida pompano Trachinotus carolinus reared to market size using recirculating aquaculture systems (RAS) at a salinity of 5 g/L was evaluated in a 110 day growth trial (water temperature, 27.0-28.5 C). Juvenile pom...

123

Evaluation of depuration procedures to mitigate off-flavor from harvest size Atlantic Salmon Salmo Salar cultured in a land-based recirculating aquaculture system  

Technology Transfer Automated Retrieval System (TEKTRAN)

Fish cultured within water recirculating aquaculture systems (RAS) can develop “earthy” or “musty” off-flavors in their flesh due to the bioaccumulation of the compounds geosmin and 2-methylisoborenol (MIB), respectively, that are produced by certain bacteria (e.g., actinomycetes). These bacteria an...

124

Evaluation of commercial marine fish feeds for production of juvenile cobia in recirculating aquaculture systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

The effect of feeding three commercially available diets manufactured by three U.S. feed companies on production characteristics and body composition of juvenile cobia Rachycentron canadum reared in recirculating aquaculture systems (RAS) was evaluated in a 57 d growth trial. Juvenile cobia (26.7 +...

125

On thermoelectric power conversion from heat re-circulating combustion systems F. J. Weinberg  

E-print Network

On thermoelectric power conversion from heat re-circulating combustion systems F. J. Weinberg Fax: 4420 7594 5604 Word count: 3750 Diags. equivalent: 1600 5350 #12;On thermoelectric power the absolute maximum efficiency of energy conversion by thermoelectric devices that operate as part of the heat

126

RECIRCULATING AQUACULTURE SYSTEM FOR MARINE FINFISH RESEARCH AT HARBOR BRANCH OCEANOGRAPHIC INSTITUTION  

Technology Transfer Automated Retrieval System (TEKTRAN)

Recirculating aquaculture systems (RAS,) for both commercial and experimental uses, has been under development in many parts of the world in response to several driving forces. With regards to sites for coastal aquaculture, the scarcity of affordable land has driven aquaculture endeavors for marine ...

127

Low-head recirculating aquaculture system for juvenile red drum production  

Technology Transfer Automated Retrieval System (TEKTRAN)

The USDA Agricultural Research Service and the Center for Aquaculture and Stock Enhancement at Harbor Branch Oceanographic Institute-FAU (HBOI-FAU) are collaborating to evaluate low-head recirculating aquaculture system designs to intensively produce red drum juveniles as part of the Florida Fish an...

128

Geosmin causes off-flavour in arctic charr in recirculating aquaculture systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

The “earthy” and “muddy” off-flavors in pond-reared fish are due to the presence of geosmin or 2-methylisoborneol (MIB) in the flesh of the fish. Similar off-flavors have been reported in fish raised in recirculating aquaculture systems (RAS); however, little information is available regarding the ...

129

Experimental Bleaching of a Reef-Building Coral Using a Simplified Recirculating Laboratory Exposure System  

EPA Science Inventory

Determining stressor-response relationships in reef building corals is a critical need for researchers because of global declines in coral reef ecosystems. A simplified recirculating coral exposure system for laboratory testing of a diversity of species and morphologies of reef b...

130

Field evaluation of a horizontal well recirculation system for groundwater treatment: Pilot test at the Clean Test Site Portsmouth Gaseous Diffusion Plant, Piketon, Ohio  

SciTech Connect

This report presents the results of field testing a horizontal well recirculation system at the Portsmouth Gaseous Diffusion Plant (PORTS). The recirculation system uses a pair of horizontal wells, one for groundwater extraction and treatment and the other for reinjection of treated groundwater, to set up a recirculation flow field. The induced flow field from the injection well to the extraction well establishes a sweeping action for the removal and treatment of groundwater contaminants. The overall purpose of this project is to study treatment of mixed groundwater contaminants that occur in a thin water-bearing zone not easily targeted by traditional vertical wells. The project involves several research elements, including treatment-process evaluation, hydrodynamic flow and transport modeling, pilot testing at an uncontaminated site, and pilot testing at a contaminated site. The results of the pilot test at an uncontaminated site, the Clean Test Site (CTS), are presented in this report.

Muck, M.T.; Kearl, P.M.; Siegrist, R.L. [and others] [and others

1998-08-01

131

A study on the optimal hydraulic loading rate and plant ratios in recirculation aquaponic system.  

PubMed

The growths of the African catfish (Clarias gariepinus) and water spinach (Ipomoea aquatica) were evaluated in recirculation aquaponic system (RAS). Fish production performance, plant growth and nutrient removal were measured and their dependence on hydraulic loading rate (HLR) was assessed. Fish production did not differ significantly between hydraulic loading rates. In contrast to the fish production, the water spinach yield was significantly higher in the lower hydraulic loading rate. Fish production, plant growth and percentage nutrient removal were highest at hydraulic loading rate of 1.28 m/day. The ratio of fish to plant production has been calculated to balance nutrient generation from fish with nutrient removal by plants and the optimum ratio was 15-42 gram of fish feed/m(2) of plant growing area. Each unit in RAS was evaluated in terms of oxygen demand. Using specified feeding regime, mass balance equations were applied to quantify the waste discharges from rearing tanks and treatment units. The waste discharged was found to be strongly dependent on hydraulic loading rate. PMID:19819130

Endut, Azizah; Jusoh, A; Ali, N; Wan Nik, W B; Hassan, A

2010-03-01

132

Formation of disinfection byproducts in a recirculating mariculture system: emerging concerns.  

PubMed

Disinfection is commonly employed in recirculating mariculture systems (RMS) to control animal diseases and improve seawater quality; however, little is known about the occurrence of disinfection byproducts (DBPs) formed in such RMS. Beijing Aquarium is a typical RMS with artificially prepared seawater and mainly adopts a decentralized treatment strategy for different animal tanks, including sand filtration, foam fractionation, and disinfection (O3, UV, and O3/ClO2). This study reveals that the adopted disinfection processes were highly effective in controlling marine heterotrophic bacteria; however, some concerns were raised on the formation of various kinds of DBPs, including secondary oxidants, inorganic oxyanions, and hazardous organic species. Free chlorine and free bromine were generated from ozonation at health-relevant concentrations. High concentrations of BrO3(-) and ClO3(-) were formed in mammal tanks, which exceeded the USEPA-regulated maximum contaminant level (MCL) for drinking water by 19-25 and 52-54 times, respectively. Extremely high concentrations of NO3(-) were detected in mammal tanks, which considerably exceeded the MCL regulated by the Sea Water Quality Standard of China for the mariculture industry (Class II) by about 1100 times. Undoubtedly, the presence of various DBPs poses serious health threats to aquarium animals. To solve these problems, potential control measures for DBPs are proposed. PMID:25573452

Qiang, Zhimin; Zhang, Haiting; Dong, Huiyu; Adams, Craig; Luan, Gang; Wang, Lei

2015-02-11

133

Evaluation of submerged surface flow (SSF) constructed wetlands for recirculating tilapia production systems  

Microsoft Academic Search

A recirculating aquaculture system (RAS) treating tilapia production wastewaters used a two-step process combining a simple clarifier and a submerged surface flow (SSF) constructed wetlands for suspended solids removal and removal of nitrogenous compounds. This system successfully supported a commercial scale level of production (>35kg\\/m3) for over 36 months of operation. The innovative SSF wetland design incorporated a high hydraulic

W ZACHRITZII; A. T. Hanson; J. A. Sauceda; K. M. Fitzsimmons

2008-01-01

134

Integrated exhaust gas recirculation and charge cooling system  

DOEpatents

An intake system for an internal combustion engine comprises an exhaust driven turbocharger configured to deliver compressed intake charge, comprising exhaust gas from the exhaust system and ambient air, through an intake charge conduit and to cylinders of the internal combustion engine. An intake charge cooler is in fluid communication with the intake charge conduit. A cooling system, independent of the cooling system for the internal combustion engine, is in fluid communication with the intake charge cooler through a cooling system conduit. A coolant pump delivers a low temperature cooling medium from the cooling system to and through the intake charge cooler for the transfer of heat from the compressed intake charge thereto. A low temperature cooler receives the heated cooling medium through the cooling system conduit for the transfer or heat therefrom.

Wu, Ko-Jen

2013-12-10

135

Florfenicol residues in Rainbow Trout after oral dosing in recirculating and flow-through culture systems  

USGS Publications Warehouse

Aquaflor is a feed premix for fish containing the broad spectrum antibacterial agent florfenicol (FFC) incorporated at a ratio of 50% (w/w). To enhance the effectiveness of FFC for salmonids infected with certain isolates of Flavobacterium psychrophilum causing coldwater disease, the FFC dose must be increased from the standard 10 mg·kg?1 body weight (BW)·d?1 for 10 consecutive days. A residue depletion study was conducted to determine whether FFC residues remaining in the fillet tissue after treating fish at an increased dose would be safe for human consumption. Groups of Rainbow Trout Oncorhynchus mykiss (total n = 144; weight range, 126–617 g) were treated with FFC at 20 mg·kg?1 BW·d?1 for 10 d in a flow-through system (FTS) and a recirculating aquaculture system (RAS) each with a water temperature of ?13°C. The two-tank RAS included a nontreated tank containing 77 fish. Fish were taken from each tank (treated tank, n = 16; nontreated tank, n = 8) at 6, 12, 24, 48, 72, 120, 240, 360, and 480 h posttreatment. Florfenicol amine (FFA) concentrations (the FFC marker residue) in skin-on fillets from treated fish were greatest at 12 h posttreatment (11.58 ?g/g) in the RAS and were greatest at 6 h posttreatment (11.09 ?g/g) in the FTS. The half-lives for FFA in skin-on fillets from the RAS and FTS were 20.3 and 19.7 h, respectively. Assimilation of FFC residues in the fillets of nontreated fish sharing the RAS with FFC-treated fish was minimal. Florfenicol water concentrations peaked in the RAS-treated tank and nontreated tanks at 10 h (453 ?g/L) and 11 h (442 ?g/L) posttreatment, respectively. Monitoring of nitrite concentrations throughout the study indicated the nitrogen oxidation efficiency of the RAS biofilter was minimally impacted by the FFC treatment.

Meinertz, Jeffery R.; Hess, Karina R.; Bernady, Jeffry A.; Gaikowski, M. P.; Whitsel, Melissa; Endris, R. G.

2014-01-01

136

Nitrification performance of nitrifiers immobilized in PVA (polyvinyl alcohol) for a marine recirculating aquarium system  

Microsoft Academic Search

Characteristics of the nitrification processes with immobilized nitrifier consortium were evaluated for the development of the marine recirculating aquarium system. In order to evaluate the activity of the nitrifiers, a 45 l airlift reactor was used for the determination of ammonia removal rate for 40 days of operation. The ammonia removal efficiency rate was 98% with 23 g ammonia-N\\/m3\\/day, respectively.

Jae-Koan Seo; Il-Hyong Jung; Mi-Ryung Kim; Byong Jin Kim; Soo-Wan Nam; Sung-Koo Kim

2001-01-01

137

An evaluation of commercially available biological filters for recirculating aquaculture systems  

Microsoft Academic Search

Three different commercially available biological filters were evaluated in triplicate on a 60m3 tank-based Tilapia system under commercial warmwater growout conditions. The study was performed at the North Carolina State University Fish Barn—a commercial scale research and demonstration recirculating aquaculture facility operated by the department of Biological and Agricultural Engineering. Total ammoniacal nitrogen (TAN) removal rates were determined for the

Todd C. Guerdat; Thomas M. Losordo; John J. Classen; Jason A. Osborne; Dennis P. DeLong

2010-01-01

138

Investigations into the reproductive performance and larval rearing of the Brown shrimp, Farfantepenaeus aztecus, using closed recirculating systems  

E-print Network

The effects of unilateral eyestalk ablation, diets and sex ratios were evaluated on two wild populations of Farfantepenaeus aztecus in a closed recirculating maturation system. Ovarian development and spawning frequencies of ablated females in both...

Gandy, Ryan Leighton

2005-02-17

139

Optimization and evaluation of a bottom substrate denitrification tank for nitrate removal from a recirculating aquaculture system.  

PubMed

A bottom substrate denitrification tank for a recirculating aquaculture system was developed. The laboratory scale denitrification tank was an 8 L tank (0.04 m2 tank surface area), packed to a depth of 5 cm with a bottom substrate for natural denitrifying bacteria. An aquarium pump was used for gentle water mixing in the tank; the dissolved oxygen in the water was maintained in aerobic conditions (e.g. > 2 mg/L) while anoxic conditions predominated only at the bottom substrate layer. The results showed that, among the four substrates tested (soil, sand, pumice stone and vermiculite), pumice was the most preferable material. Comparing carbon supplementation using methanol and molasses, methanol was chosen as the carbon source because it provided a higher denitrification rate than molasses. When methanol was applied at the optimal COD:N ratio of 5:1, a nitrate removal rate of 4591 +/- 133 mg-N/m2 tank bottom area/day was achieved. Finally, nitrate removal using an 80 L denitrification tank was evaluated with a 610 L recirculating tilapia culture system. Nitrate treatment was performed by batch transferring high nitrate water from the nitrification tank into the denitrification tank and mixing with methanol at a COD:N ratio of 5:1. The results from five batches of nitrate treatment revealed that nitrate was successfully removed from water without the accumulation of nitrite and ammonia. The average nitrate removal efficiency was 85.17% and the average denitrification rate of the denitrification tank was 6311 +/- 945 mg-N/m2 tank bottom area/day or 126 +/- 18 mg-N/L of pumice packing volume/day. PMID:24520693

Pungrasmi, Wiboonluk; Playchoom, Cholticha; Powtongsook, Sorawit

2013-08-01

140

Production Characteristics and Body Composition of Florida Pompano Reared to Market Size at Two Different Densities in Low-Salinity Recirculating Aquaculture Systems  

Microsoft Academic Search

The effect of culture density on production characteristics and body composition of Florida pompano Trachinotus carolinus reared to market size using recirculating aquaculture systems (RASs) maintained at a salinity of 5‰ was evaluated in a 110-d growth trial (water temperature = 27.0–28.5°C). Juvenile Florida pompano (mean weight ± SE = 259.0 ± 3.0 g) were stocked into two tanks from

Charles R. Weirich; Paul S. Wills; Richard M. Baptiste; Peter N. Woodward; Marty A. Riche

2009-01-01

141

Bacterial diversity, community structure and function associated with biofilm development in a biological aerated filter in a recirculating marine aquaculture system  

Microsoft Academic Search

A biological aerated filter (100 l), filled with bamboo ball media, was set up for treatment of low ammonia-containing recirculating\\u000a water in a marine aquaculture system. Chemical analysis showed that it took 70 days to establish a stable efficiency, at which\\u000a more than 30% of the ammonia was removed. During the biofilm development, bacterial diversity and community structure were\\u000a determined by construction

Xi-Yan Gao; Yang Xu; Ying Liu; Zhi-Pei Liu

142

Argon purification studies and a novel liquid argon re-circulation system  

NASA Astrophysics Data System (ADS)

Future giant liquid argon (LAr) time projection chambers (TPCs) require a purity of better than 0.1 parts per billion (ppb) to allow the ionised electrons to drift without significant capture by any electronegative impurities. We present a comprehensive study of the effects of electronegative impurity on gaseous and liquid argon scintillation light, an analysis of the efficiency of various purification chemicals, as well as the Liverpool LAr setup, which utilises a novel re-circulation purification system. Of the impurities tested - Air, O2, H2O, N2 and CO2 in the range of between 0.01 ppm to 1000 ppm - H2O was found to have the most profound effect on gaseous argon scintillation light, and N2 was found to have the least. Additionally, a correlation between the slow component decay time and the total energy deposited with 0.01 ppm - 100 ppm O2 contamination levels in liquid argon has been established. The superiority of molecular sieves over anhydrous complexes at absorbing Ar gas, N2 gas and H2O vapour has been quantified using BET isotherm analysis. The efficiency of Cu and P2O5 at removing O2 and H2O impurities from 1 bar N6 argon gas at both room temperature and -130 °C was investigated and found to be high. A novel, highly scalable LAr re-circulation system has been developed. The complete system, consisting of a motorised bellows pump operating in liquid and a purification cartridge, were designed and built in-house. The system was operated successfully over many days and achieved a re-circulation rate of 27 litres/hour and high purity.

Mavrokoridis, K.; Calland, R. G.; Coleman, J.; Lightfoot, P. K.; McCauley, N.; McCormick, K. J.; Touramanis, C.

2011-08-01

143

Development and design of a fluidized bed/upflow sand filter configuration for use in recirculating aquaculture systems  

SciTech Connect

A fluidized bed/upflow sand filter configuration, was developed and designed for utilization in recirculating aquaculture system, specifically the soft-shell crab and soft-shell crawfish industries. These filters were selected and designed because of their ability to withstand clogging and still maintain high levels of water quality for aquaculture production. The effectiveness of sand grain size was used to evaluate fluidized bed filter performance with filter loadings ranging from 16 to 1285 pounds of crawfish per cubic foot of filter sand. A coarse sand grain size was recommended as a filter media because of it's ability to shear excessive biofilm growth from the and, thus prohibiting clogging from occurring within the filter bed. The fluidized bed/upflow sand filter combination was evaluated in terms of nitrification and oxygen consumption when used with a recirculating crab shedding system. The filter combination's carrying capacity (700 crabs per cubic foot of sand media) exceeded that observed with the submerged rock filter by more than 20 times and was largely explained by the filter's solids removal ability which significantly reduced the filter's oxygen loading rate (OLR). Nitrification rates with the filter combination were extremely high as total ammonia and nitrite levels remained below 1.0 mg-N/l. Verification of a volumetric loading criteria (150 pounds per cubic foot) for this filter combination was further established with performance data obtained from a commercial soft-shell crawfish facility. Water quality monitoring results indicated that the filters maintained total ammonia and nitrite levels below 1.0 mg-N/l under typical operating conditions. Shock loading, pH control, and over-feeding, rather than filter capacity, dominated water quality fluctuations, thereby indicating that the loading criteria was sufficient for commercial operation.

Burden, D.G.

1988-01-01

144

Recirculation anaesthesia for laboratory fish  

Microsoft Academic Search

Summary An economic reliable long-term recirculation anaesthesia system for laboratory fish is des- cribed. Anaesthesia of channel catfish (\\/ctalurus punctatus Rafinesque) was induced within 60 s and was maintained for up to 40 min using tricaine methanesulphonate; recovery occurred within 30-60 s. Various surgical procedures were performed on the fish. No deaths were recorded. All water-quality parameters tested over 19

L. A. Brown

1987-01-01

145

Florfenicol Residues in Rainbow Trout after Oral Dosing in Recirculating and Flow-through Culture Systems.  

PubMed

Abstract Aquaflor is a feed premix for fish containing the broad spectrum antibacterial agent florfenicol (FFC) incorporated at a ratio of 50% (w/w). To enhance the effectiveness of FFC for salmonids infected with certain isolates of Flavobacterium psychrophilum causing coldwater disease, the FFC dose must be increased from the standard 10 mg·kg(-1) body weight (BW)·d(-1) for 10 consecutive days. A residue depletion study was conducted to determine whether FFC residues remaining in the fillet tissue after treating fish at an increased dose would be safe for human consumption. Groups of Rainbow Trout Oncorhynchus mykiss (total n = 144; weight range, 126-617 g) were treated with FFC at 20 mg·kg(-1) BW·d(-1) for 10 d in a flow-through system (FTS) and a recirculating aquaculture system (RAS) each with a water temperature of ?13°C. The two-tank RAS included a nontreated tank containing 77 fish. Fish were taken from each tank (treated tank, n = 16; nontreated tank, n = 8) at 6, 12, 24, 48, 72, 120, 240, 360, and 480 h posttreatment. Florfenicol amine (FFA) concentrations (the FFC marker residue) in skin-on fillets from treated fish were greatest at 12 h posttreatment (11.58 ?g/g) in the RAS and were greatest at 6 h posttreatment (11.09 ?g/g) in the FTS. The half-lives for FFA in skin-on fillets from the RAS and FTS were 20.3 and 19.7 h, respectively. Assimilation of FFC residues in the fillets of nontreated fish sharing the RAS with FFC-treated fish was minimal. Florfenicol water concentrations peaked in the RAS-treated tank and nontreated tanks at 10 h (453 ?g/L) and 11 h (442 ?g/L) posttreatment, respectively. Monitoring of nitrite concentrations throughout the study indicated the nitrogen oxidation efficiency of the RAS biofilter was minimally impacted by the FFC treatment. Received January 8, 2014; accepted July 7, 2014. PMID:25321636

Meinertz, J R; Hess, K R; Bernardy, J A; Gaikowski, M P; Whitsel, M; Endris, R G

2014-12-01

146

Advanced water iodinating system. [for potable water aboard manned spacecraft  

NASA Technical Reports Server (NTRS)

Potable water stores aboard manned spacecraft must remain sterile. Suitable sterilization techniques are needed to prevent microbial growth. The development of an advanced water iodinating system for possible application to the shuttle orbiter and other advanced spacecraft, is considered. The AWIS provides a means of automatically dispensing iodine and controlling iodination levels in potable water stores. In a recirculation mode test, simulating application of the AWIS to a water management system of a long term six man capacity space mission, noniodinated feed water flowing at 32.2 cu cm min was iodinated to 5 + or - ppm concentrations after it was mixed with previously iodinated water recirculating through a potable water storage tank. Also, the AWIS was used to successfully demonstrate its capability to maintain potable water at a desired I2 concentration level while circulating through the water storage tank, but without the addition of noniodinated water.

Davenport, R. J.; Schubert, F. H.; Wynveen, R. A.

1975-01-01

147

Treatment of fishpond water by recirculating horizontal and vertical flow constructed wetlands in the tropics  

Microsoft Academic Search

Common practice of aquaculture in Vietnam and other countries in South East Asia involves frequent discharge of polluted water into rivers which results in eutrophication and degradation of receiving water bodies. There is therefore a need to develop improved aquaculture systems which have a more efficient use of water and less environmental impact. The aim of this study was to

Dennis Konnerup; Ngo Thuy Diem Trang; Hans Brix

2011-01-01

148

Electron recirculation in electrostatic multicusp systems: II. System performance scaling of one-dimensional rollover wells  

SciTech Connect

In an earlier paper a comprehensive study was made of the recirculation and losses of electrons in their flow through simple inverse power-law potential wells bounded by similarly inverse power-law dependent magnetic fields. This study examined electron flow and loss behavior in the simplest approximation invoked to describe Polywell confinement systems. The importance of this study, and of the present paper, is that the power balance in Polywell systems is determined entirely by the rate of electron losses; if these are large, then the system can not yield net power. Thus it is of interest to determine those conditions that results in small losses, and to design experiments and systems to attempt to achieve and operate at these most favorable conditions, in order to test and prove the efficacy of the system for the generation of net power from fusion reactions. The outline and summary of this problem presented is generally repeated here, with some modifications to clarify particular physics issues of most concern, in order to avoid having to refer to the earlier document for this general description. As noted, a large body of work has been undertaken over the past 35 or so years in the study of general cusp confinement of plasmas. Nearly all of this has examined single particle electron (or ion) motion or the motion of particles in neutral plasmas within cusped magnetic systems, generally without internal electric potential fields.**INVALID KEYWORDS: controlled nuclear fusion, electron flux, plasma devices, confinement, performance, engineering, scaling factor, multicusp systems, polywell systems

Bussard, R.W.; King, K.E.

1992-01-01

149

Anoxic gas recirculation system for fouling control in anoxic membrane reactor.  

PubMed

Anoxic gas recirculation system was applied to control the membrane fouling in pilot-scale 4-stage anoxic membrane bioreactor (MBR). In the anaerobic-anoxic-anoxic-aerobic flow scheme, hydrophilic polytetrafluoroethylene (PTFE) membrane (0.2 ?m, 7.2 m(2)/module) was submerged in the second anoxic zone. During 8 months operation, the average flux of the membrane was 21.3 L/(m(2)·hr). Chemical cleaning of the membrane was conducted only once with sodium hydroxide and sodium hypochlorite. Dissolved oxygen (DO) concentration in the second anoxic zone was maintained with an average of 0.19 ± 0.05 mg/L. Gas chromatography analysis showed that the headspace gas in the second anoxic reactor was mainly consisted of N2 (93.0% ± 2.5%), O2 (3.8% ± 0.6%), and CO2 (3.0% ± 0.5%), where the saturation DO concentration in liquid phase was 1.57 mg/L. Atmospheric O2 content (20.5% ± 0.8%) was significantly reduced in the anoxic gas. The average pH in the reactor was 7.2 ± 0.4. As a result, the recirculation of the anoxic gas was successfully applied to control the membrane fouling in the anoxic MBR. PMID:25079838

Lee, Hansaem; Lee, Daeju; Hong, Seongwan; Yun, Geum Hee; Kim, Sungpyo; Hwang, Jung Ki; Lee, Woojae; Yun, Zuwhan

2014-06-01

150

Effect of stocking density on performances of juvenile turbot ( Scophthalmus maximus) in recirculating aquaculture systems  

NASA Astrophysics Data System (ADS)

Limited information has been available about the influence of loading density on the performances of Scophthalmus maximus, especially in recirculating aquaculture systems (RAS). In this study, turbot (13.84±2.74 g; average weight±SD) were reared at four different initial densities (low 0.66, medium 1.26, sub-high 2.56, high 4.00 kg/m2) for 10 weeks in RAS at 23±1°C. Final densities were 4.67, 7.25, 14.16, and 17.47 kg/m2, respectively, which translate to 82, 108, 214, and 282 percent coverage of the tank bottom. Density had both negative and independent impacts on growth. The final mean weight, specific growth rate (SGR), and voluntary feed intake significantly decreased and the coefficient of variation (CV) of final body weight increased with increase in stocking density. The medium and sub-high density groups did not differ significantly in SGR, mean weight, CV, food conversion rate (FCR), feed intake, blood parameters, and digestive enzymes. The protease activities of the digestive tract at pH 7, 8.5, 9, and 10 were significantly higher for the highest density group, but tended to be lower (not significantly) at pH 4 and 8.5 for the lowest density group. The intensity of protease activity was inversely related to feed intake at the different densities. Catalase activity was higher (but not significantly) at the highest density, perhaps because high density started to induce an oxidative effect in turbot. In conclusion, turbot can be cultured in RAS at a density of less than 17.47 kg/m2. With good water quality and no feed limitation, initial density between 1.26 and 2.56 kg/m2 (final: 7.25 and 14.16 kg/m2) would not negatively affect the turbot cultured in RAS. For culture at higher density, multi-level feeding devices are suggested to ease feeding competition.

Li, Xian; Liu, Ying; Blancheton, Jean-Paul

2013-05-01

151

A Mathematical Model of Solute Coupled Water Transport in Toad Intestine Incorporating Recirculation of the Actively Transported Solute  

PubMed Central

A mathematical model of an absorbing leaky epithelium is developed for analysis of solute coupled water transport. The non-charged driving solute diffuses into cells and is pumped from cells into the lateral intercellular space (lis). All membranes contain water channels with the solute passing those of tight junction and interspace basement membrane by convection-diffusion. With solute permeability of paracellular pathway large relative to paracellular water flow, the paracellular flux ratio of the solute (influx/outflux) is small (2–4) in agreement with experiments. The virtual solute concentration of fluid emerging from lis is then significantly larger than the concentration in lis. Thus, in absence of external driving forces the model generates isotonic transport provided a component of the solute flux emerging downstream lis is taken up by cells through the serosal membrane and pumped back into lis, i.e., the solute would have to be recirculated. With input variables from toad intestine (Nedergaard, S., E.H. Larsen, and H.H. Ussing, J. Membr. Biol. 168:241–251), computations predict that 60–80% of the pumped flux stems from serosal bath in agreement with the experimental estimate of the recirculation flux. Robust solutions are obtained with realistic concentrations and pressures of lis, and with the following features. Rate of fluid absorption is governed by the solute permeability of mucosal membrane. Maximum fluid flow is governed by density of pumps on lis-membranes. Energetic efficiency increases with hydraulic conductance of the pathway carrying water from mucosal solution into lis. Uphill water transport is accomplished, but with high hydraulic conductance of cell membranes strength of transport is obscured by water flow through cells. Anomalous solvent drag occurs when back flux of water through cells exceeds inward water flux between cells. Molecules moving along the paracellular pathway are driven by a translateral flow of water, i.e., the model generates pseudo-solvent drag. The associated flux-ratio equation is derived. PMID:10919860

Larsen, Erik Hviid; Sørensen, Jakob Balslev; Sørensen, Jens Nørkær

2000-01-01

152

Characterization of the microbial community and nitrogen transformation processes associated with moving bed bioreactors in a closed recirculated mariculture system  

Microsoft Academic Search

The microbial consortium of a moving bed bioreactor (MBB) connected to a marine recirculating aquaculture system was examined by denaturing gradient gel electrophoresis (DGGE) of amplified 16S rRNA gene fragments. Both ammonia and nitrite oxidizers, Nitrosomonas cryotolerans and Nitrospira marina, respectively, were found associated with the marine system as well as a number of heterotrophic bacteria, including Pseudomonas sp. and

Yossi Tal; Joy E. M. Watts; Susan B. Schreier; Kevin R. Sowers; Harold J. Schreier

2003-01-01

153

Design and function of a closed, recirculating seawater system with denitrification for the culture of black tiger shrimp broodstock  

Microsoft Academic Search

A closed, recirculating seawater system with a denitrification process was designed for the culture of black tiger shrimp broodstock. The system comprised a circular rearing tank (9 m3 volume), a nitrifying biofilter (6 m3 volume) and denitrification process. The denitrification process comprised a deoxygenation column, a bacterial substrate column (143 L volume) and a re-aeration column connected to the biofilter.

Piamsak Menasveta; Tanya Panritdam; Pakitsin Sihanonth; Sorawit Powtongsook; Benjamas Chuntapa; Phillip Lee

2001-01-01

154

Performance of a closed recirculating system with foam separation, nitrification and denitrification units for intensive culture of eel: towards zero emission  

Microsoft Academic Search

The development of a closed recirculating aquaculture system that does not discharge effluents would reduce a large amount of pollutant load on aquatic bodies. In this study, eel were reared in a closed recirculating system, which consisted of a rearing tank, a foam separation unit, a nitrification unit and a denitrification unit. The foam separation unit has an inhalation-type aerator

Yoshihiro Suzuki; Toshiroh Maruyama; Hiroyuki Numata; Hajime Sato; Makio Asakawa

2003-01-01

155

Comparison of aerobically-treated and untreated crop residue as a source of recycled nutrients in a recirculating hydroponic system  

NASA Technical Reports Server (NTRS)

This study compared the growth of potato plants on nutrients recycled from inedible potato biomass. Plants were grown for 105 days in recirculating, thin-film hydroponic systems containing four separate nutrient solution treatments: (1) modified half-strength Hoagland's (control), 2) liquid effluent from a bioreactor containing inedible potato biomass, 3) filtered (0.2 micrometer) effluent, and 4) the water soluble fraction of inedible potato biomass (leachate). Approximately 50% of the total nutrient requirement in treatments 2-4 were provided (recycled) from the potato biomass. Leachate had an inhibitory effect on leaf conductance, photosynthetic rate, and growth (50% reduction in plant height and 60% reduction in tuber yield). Plants grown on bioreactor effluent (filtered or unfiltered) were similar to the control plants. These results indicated that rapidly degraded, water soluble organic material contained in the inedible biomass, i.e., material in leachate, brought about phytotoxicity in the hydroponic culture of potato. Recalcitrant, water soluble organic material accumulated in all nutrient recycling treatments (650% increase after 105 days), but no increase in rhizosphere microbial numbers was observed.

Mackowiak, C. L.; Garland, J. L.; Strayer, R. F.; Finger, B. W.; Wheeler, R. M.

1996-01-01

156

Comparison of aerobically-treated and untreated crop residue as a source of recycled nutrients in a recirculating hydroponic system  

NASA Astrophysics Data System (ADS)

This study compared the growth of potato plants on nutrients recycled from inedible potato biomass. Plants were grown for 105 days in recirculating, thin-film hydroponic systems containing four separate nutrient solution treatments: 1) modified half-strength Hoagland's (control), 2) liquid effluent from a bioreactor containing inedible potato biomass, 3) filtered (0.2 ?m) effluent, and 4) the water soluble fraction of inedible potato biomass (leachate). Approximately 50% of the total nutrient requirement in treatments 2 - 4 were provided (recycled) from the potato biomass. Leachate had an inhibitory effect on leaf conductance, photosynthetic rate, and growth (50% reduction in plant height and 60% reduction in tuber yield). Plants grown on bioreactor effluent (filtered or unfiltered) were similar to the control plants. These results indicated that rapidly degraded, water soluble organic material contained in the inedible biomass, i.e., material in leachate, brought about phytotoxicity in the hydroponic culture of potato. Recalcitrant, water soluble organic material accumulated in all nutrient recycling treatments (650% increase after 105 days), but no increase in rhizosphere microbial numbers was observed.

Mackowiak, C. L.; Garland, J. L.; Strayer, R. F.; Finger, B. W.; Wheeler, R. M.

1996-01-01

157

Evaluation of a low-head recirculating aquaculture system used for rearing Florida pompano to market size  

Technology Transfer Automated Retrieval System (TEKTRAN)

A low-head recirculating aquaculture system (RAS) was evaluated for the production Florida pompano Trachinotus carolinus from juvenile to market size. The RAS consisted of three dual-drain, 3-m diameter culture tanks of 7.8 m3 volume each, two 0.7-m3 moving bed bioreactors filled 67% with K1 kaldnes...

158

Dynamic Control of Engine NOx Emissions: Characterization and Improvement of the Transient Response of an Exhaust Gas Recirculation System  

Microsoft Academic Search

An effective method for reducing NOx emissions from automotive engines is to use exhaust gas recirculation (EGR) to dilute the inducted air-fuel charge. Previous work has shown that degraded propagation delay and rise time characteristics of an EGR system can result in increases in NOx emissions for engine operation over dynamic rpm\\/torque versus time trajectories as exemplified by the Federal

M. J. Throop; D. R. Hamburg

1985-01-01

159

Preliminary studies on the depuration of common off-flavors from fish raised in recirculating aquaculture systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

“Off-flavor” problems can adversely impact the growth of the aquaculture industry. Fish raised in recirculating systems have the potential to develop the common off-flavors “earthy” and “musty” due to accumulation of the microbial metabolites geosmin and 2-methylisoborneol (MIB) in the fish flesh. ...

160

High ratio recirculating gas compressor  

DOEpatents

A high ratio positive displacement recirculating rotary compressor is disclosed. The compressor includes an integral heat exchanger and recirculation conduits for returning cooled, high pressure discharge gas to the compressor housing to reducing heating of the compressor and enable higher pressure ratios to be sustained. The compressor features a recirculation system which results in continuous and uninterrupted flow of recirculation gas to the compressor with no direct leakage to either the discharge port or the intake port of the compressor, resulting in a capability of higher sustained pressure ratios without overheating of the compressor.

Weinbrecht, John F. (601 Oakwood Pl., NE., Albuquerque, NM 87123)

1989-01-01

161

High ratio recirculating gas compressor  

DOEpatents

A high ratio positive displacement recirculating rotary compressor is disclosed. The compressor includes an integral heat exchanger and recirculation conduits for returning cooled, high pressure discharge gas to the compressor housing to reducing heating of the compressor and enable higher pressure ratios to be sustained. The compressor features a recirculation system which results in continuous and uninterrupted flow of recirculation gas to the compressor with no direct leakage to either the discharge port or the intake port of the compressor, resulting in a capability of higher sustained pressure ratios without overheating of the compressor. 10 figs.

Weinbrecht, J.F.

1989-08-22

162

Optimal white water and broke recirculation policies in paper mills via jump linear quadratic control  

Microsoft Academic Search

With the increasing closure of white water circuits in paper mills, breaks in the sheet of paper have become a system-wide disturbance. Upon recognizing that such breaks can be modeled as a Markov chain type of process which, when interacting with the continuous mill dynamics, yields a jump Markov model, jump linear theory is proposed as a means of constructing

Maryam Khanbaghi; Roland P. Malhamé; Michel Perrier

2002-01-01

163

Optimization of two-phase thermophilic anaerobic digestion of biowaste for hydrogen and methane production through reject water recirculation.  

PubMed

The optimization of a two-phase thermophilic anaerobic process treating biowaste for hydrogen and methane production was carried out at pilot scale using two stirred reactors (CSTRs) and without any physical/chemical pre-treatment of inoculum. During the experiment the hydrogen production at low hydraulic retention time (3d) was tested, both with and without reject water recirculation and at two organic loading rate (16 and 21 kgTVS/m3 d). The better yields were obtained with recirculation where the pH reached an optimal value (5.5) thanks to the buffering capacity of the recycle stream. The specific gas production of the first reactor was 51 l/kgVS(fed) and H2 content in biogas 37%. The mixture of gas obtained from the two reactors met the standards for the biohythane mix only when lower loading rate were applied to the first reactor, with a composition of 6.7% H2, 40.1% CO2 and 52.3% CH4 the overall SGP being 0.78 m3/kgVS(fed). PMID:21511465

Cavinato, C; Bolzonella, D; Fatone, F; Cecchi, F; Pavan, P

2011-09-01

164

Depletion of florfenicol amine in tilapia (Oreochromis sp.) maintained in a recirculating aquaculture system following Aquaflor®-medicated feed therapy  

USGS Publications Warehouse

Aquaflor® [50% w w?1 florfenicol (FFC)], is approved for use in freshwater-reared warmwater finfish which include tilapia Oreochromis spp. in the United States to control mortality from Streptococcus iniae. The depletion of florfenicol amine (FFA), the marker residue of FFC, was evaluated after feeding FFC-medicated feed to deliver a nominal 20 mg FFC kg?1 BW d?1 dose (1.33× the label use of 15 mg FFC kg?1 BW d?1) to Nile tilapia O. niloticus and hybrid tilapia O. niloticus × O. aureus held in a recirculating aquaculture system (RAS) at production-scale holding densities. Florfenicol amine concentrations were determined in fillets taken from 10 fish before dosing and from 20 fish at nine time points after dosing (from 1 to 240 h post-dosing). Water samples were assayed for FFC before, during and after the dosing period. Parameters monitored included daily feed consumption and biofilter function (levels of ammonia, nitrite and nitrate). Mean fillet FFA concentration decreased from 13.77 ?g g?1 at 1-h post dosing to 0.39 ?g g?1 at 240-h post dosing. Water FFC concentration decreased from a maximum of 1400 ng mL?1 at 1 day post-dosing to 847 ng mL?1 at 240 h post-dosing. There were no adverse effects noted on fish, feed consumption or biofilter function associated with FFC-medicated feed administration to tilapia.

Gaikowski, Mark P.; Whitsel, Melissa K.; Charles, Shawn; Schleis, Susan M.; Crouch, Louis S.; Endris, Richard G.

2013-01-01

165

Application of CFD modeling to hydrodynamics of CycloBio fluidized sand bed in recirculating aquaculture systems  

NASA Astrophysics Data System (ADS)

To improve the efficiency of a CycloBio fluidized sand bed (CB FSB) in removal of dissolved wastes in recirculating aquaculture systems, the hydrodynamics of solid-liquid flow was investigated using computational fluid dynamics (CFD) modeling tools. The dynamic characteristics of silica sand within the CB FSB were determined using three-dimensional, unsteady-state simulations with the granular Eulerian multiphase approach and the RNG k-? turbulence model, and the simulation results were validated using available lab-scale measurements. The bed expansion of CB FSB increased with the increase in water inflow rate in numerical simulations. Upon validation, the simulation involving 0.55 mm particles, the Gidaspow correlation for drag coefficient model and the Syamlal-O'Brien correlation for kinetic granular viscosity showed the closest match to the experimental results. The volume fraction of numerical simulations peaked as the wall was approached. The hydrodynamics of a pilot-scale CB FSB was simulated in order to predict the range of water flow to avoid the silica sand overflowing. The numerical simulations were in agreement with the experimental results qualitatively and quantitatively, and thus can be used to study the hydrodynamics of solid-liquid multiphase flow in CB FSB, which is of importance to the design, optimization, and amplification of CB FSBs.

Liu, Yao; Song, Xiefa; Liang, Zhenlin; Peng, Lei

2013-11-01

166

Review article Disinfestation of recirculating nutrient solutions  

E-print Network

Review article Disinfestation of recirculating nutrient solutions in greenhouse horticulture David) Abstract ­ Recirculating nutrient systems offer a good method to control nutrient leaching from greenhouses of recirculating nutrient systems by the greenhouse industry. This review discusses and compares five broadly

Boyer, Edmond

167

Graywater processing in recirculating hydroponic systems: phytotoxicity, surfactant degradation, and bacterial dynamics  

Microsoft Academic Search

Incorporation of human hygiene water (graywater) into hydroponic plant production systems, and subsequent recovery of the water transpired by the plants, is one potential means for water purification and recycling in bioregenerative life support systems under development for long duration space missions. Surfactant phytotoxicity and the potential for growth of human-associated microorganisms were assessed in studies of wheat and lettuce

J. L Garland; L. H Levine; N. C Yorio; J. L Adams; K. L Cook

2000-01-01

168

Advanced Horizontal Well Recirculation Systems for Geothermal Energy Recovery in Sedimentary Formations  

SciTech Connect

There is increased recognition that geothermal energy resources are more widespread than previously thought, with potential for providing a significant amount of sustainable clean energy worldwide. Recent advances in drilling, completion, and production technology from the oil and gas industry can now be applied to unlock vast new geothermal resources, with some estimates for potential electricity generation from geothermal energy now on the order of 2 million megawatts. Terralog USA, in collaboration with the University of California, Irvine (UCI), are currently investigating advanced design concepts for paired horizontal well recirculation systems, optimally configured for geothermal energy recovery in permeable sedimentary and crystalline formations of varying structure and material properties. This two-year research project, funded by the US Department of Energy, includes combined efforts for: 1) Resource characterization; 2) Small and large scale laboratory investigations; 3) Numerical simulation at both the laboratory and field scale; and 4) Engineering feasibility studies and economic evaluations. The research project is currently in its early stages. This paper summarizes our technical approach and preliminary findings related to potential resources, small-scale laboratory simulation, and supporting numerical simulation efforts.

Mike Bruno; Russell L. Detwiler; Kang Lao; Vahid Serajian; Jean Elkhoury; Julia Diessl; Nicky White

2012-09-30

169

Utilization of waste from a marine recirculating fish culture system as a feed source for the polychaete worm, Nereis virens  

Microsoft Academic Search

Two experiments were conducted to test the effect of feeding the polychaete worm Nereis virens with solid wastes collected from a marine recirculating system. In experiment 1, worms with an initial mean weight of 0.37g were fed for 80days with a commercial worm diet (CD), halibut fecal waste (FW), uneaten halibut feed pellets (PW) or a 1:1 mixture of fecal

Nicholas Brown; Stephen Eddy; Stefanie Plaud

170

Effects of Biofilter\\/Culture Tank Volume Ratios on Productivity of a Recirculating Fish\\/Vegetable Co-Culture System  

Microsoft Academic Search

The effects of four biofilter volume (BFV)\\/culture tank volume ratios (0.67\\/1, 1.00\\/1, 1.50\\/1, and 2.25\\/1) on biofilter function were examined in a recirculating fish\\/vegetable production system in a greenhouse. Sand beds served as biofilters, as substrate for vegetable growth, and as location for decomposition of waste solids. No fertilizer was used. Three experiments were conducted over the course of one

M. R. McMurtry; D. C. Sanders; J. D. Cure; R. G. Hodson

1997-01-01

171

Commissioning the Domestic Hot Water System on a Large University Campus: A Case Study  

E-print Network

distance of several miles from either). It is aerated to cool and remove dissolved gases at the TAMU Wellfield water treatment facility. Water is then chlorinated and pumped approximately 7 miles to campus. DHW is made in the central utilities plant... strategies for domestic hot water recirculation systems?. ASHRAE Transactions, v 105, pt 1, 1999, p 1030-1048. Killmeier, E., F., 1998. ?Domestic hot water balancing?. TAB Journal, Winter, 1998, p 4-6. Penny, D., S., 1990. ?Balancing domestic recirculated...

Chen, H.; Bensouda, N.; Claridge, D.; Bruner, H.

2004-01-01

172

Design keys of a recent recirculating facility built in Chile operating with fluidized bed biofilters  

Microsoft Academic Search

The fast evolution of recirculation systems for salmonids has challenged the engineering companies to develop new and better design and engineering practices, to improve the water quality and system flexibility. One of the major factors that affect the water quality parameters is the total suspended solids produced within the system. The design of water flow from the water inlet into

Rafael I. Morey

2009-01-01

173

Exhaust gas recirculation control  

Microsoft Academic Search

A transducer regulates an operating pressure which positions an exhaust gas recirculation control valve pintle to provide exhaust gas recirculation at rates which maintain the pressure in the recirculation passage upstream of the valve pintle equal to a reference pressure; exhaust gas recirculation thus varies with engine exhaust backpressure and accordingly is substantially proportional to induction air flow. The transducer

Haka

1979-01-01

174

Colwellia aquaemaris sp. nov., isolated from the Cynoglossus semilaevis culture tank in a recirculating mariculture system.  

PubMed

A Gram-staining-negative, heterotrophic, facultatively anaerobic bacterium, designated S1(T), was isolated from the Cynoglossus semilaevis culture pond in a recirculating mariculture system in Tianjin, China. The taxonomy of strain S1(T) was studied by using a polyphasic approach. Cells of strain S1(T) were non-spore-forming, curved rods, 0.4-0.6 µm wide and 1.2-2.0 µm long, and motile by means of a single polar flagellum. The strain was positive for oxidase and catalase activities. Strain S1(T) was able to grow at 4-30 °C (optimum, 25 °C), at pH 5.5-10.0 (optimum, pH 6.5-7.5) and in the presence of 1-5?% (w/v) NaCl (optimum, 2?%). Strain S1(T) contained Q-8 as the sole respiratory quinone and C16?:?1?7c/C16?:?1?6c and C16?:?0 as the predominant cellular fatty acids. The genomic DNA G+C content was 40.1 mol% (Tm). Phylogenetic analysis based on 16S rRNA gene sequences placed strain S1(T) in the genus Colwellia, and it formed a distinct lineage in the phylogenetic tree together with Colwellia meonggei MA1-3(T), Colwellia aestuarii SMK-10(T), Colwellia polaris 537(T) and Colwellia chukchiensis BCw111(T), with 97.7, 96.1, 95.9 and 95.0?% 16S rRNA gene sequence similarity to these strains, respectively. DNA-DNA relatedness of strain S1(T) to Colwellia meonggei MA1-3(T) was 23.5±3.6?%. On the basis of the phylogenetic and phenotypic evidence, strain S1(T) is considered to represent a novel species of the genus Colwellia, for which the name Colwellia aquaemaris sp. nov. is proposed. The type strain is S1(T) (?=?CGMCC 1.12165(T)?=?JCM 18479(T)). PMID:25201915

Liu, Ying; Liu, Liang-Zi; Zhong, Zhi-Ping; Zhou, Yu-Guang; Liu, Ying; Liu, Zhi-Pei

2014-12-01

175

Soil nitrifying enrichments as biofilter starters in intensive recirculating saline water aquaculture  

E-print Network

aquaculture Amit Grossa , Anna Nemirovskya , Dina Zilbergb , Anna Khaimova , Asher Brennerc , Eviatar Snird aquaculture relies on biofilters to sustain satisfactory water quality in the ponds. Establishment of new biofilters in aquaculture ponds without a start-up culture requires a long period of time and may therefore

Gross, Amit

176

Bacterially mediated removal of phosphorus and cycling of nitrate and sulfate in the waste stream of a "zero-discharge" recirculating mariculture system.  

PubMed

Simultaneous removal of nitrogen and phosphorus by microbial biofilters has been used in a variety of water treatment systems including treatment systems in aquaculture. In this study, phosphorus, nitrate and sulfate cycling in the anaerobic loop of a zero-discharge, recirculating mariculture system was investigated using detailed geochemical measurements in the sludge layer of the digestion basin. High concentrations of nitrate and sulfate, circulating in the overlying water (?15 mM), were removed by microbial respiration in the sludge resulting in a sulfide accumulation of up to 3 mM. Modelling of the observed S and O isotopic ratios in the surface sludge suggested that, with time, major respiration processes shifted from heterotrophic nitrate and sulfate reduction to autotrophic nitrate reduction. The much higher inorganic P content of the sludge relative to the fish feces is attributed to conversion of organic P to authigenic apatite. This conclusion is supported by: (a) X-ray diffraction analyses, which pointed to an accumulation of a calcium phosphate mineral phase that was different from P phases found in the feces, (b) the calculation that the pore waters of the sludge were highly oversaturated with respect to hydroxyapatite (saturation index = 4.87) and (c) there was a decrease in phosphate (and in the Ca/Na molar ratio) in the pore waters simultaneous with an increase in ammonia showing there had to be an additional P removal process at the same time as the heterotrophic breakdown of organic matter. PMID:24657541

Krom, M D; Ben David, A; Ingall, E D; Benning, L G; Clerici, S; Bottrell, S; Davies, C; Potts, N J; Mortimer, R J G; van Rijn, J

2014-06-01

177

Anaerobic Ammonium-Oxidizing (Anammox) Bacteria and Associated Activity in Fixed-Film Biofilters of a Marine Recirculating Aquaculture System  

PubMed Central

Microbial communities in the biological filter and waste sludge compartments of a marine recirculating aquaculture system were examined to determine the presence and activity of anaerobic ammonium-oxidizing (anammox) bacteria. Community DNA was extracted from aerobic and anaerobic fixed-film biofilters and the anaerobic sludge waste collection tank and was analyzed by amplifying 16S rRNA genes by PCR using anammox-selective and universal GC-clamped primers. Separation of amplified PCR products by denaturing gradient gel electrophoresis and sequencing of the different phylotypes revealed a diverse biofilter microbial community. While Planctomycetales were found in all three communities, the anaerobic denitrifying biofilters contained one clone that exhibited high levels of sequence similarity to known anammox bacteria. Fluorescence in situ hybridization studies using an anammox-specific probe confirmed the presence of anammox Planctomycetales in the microbial biofilm from the denitrifying biofilters, and anammox activity was observed in these biofilters, as detected by the ability to simultaneously consume ammonia and nitrite. To our knowledge, this is the first identification of anammox-related sequences in a marine recirculating aquaculture filtration system, and our findings provide a foundation for incorporating this important pathway for complete nitrogen removal in such systems. PMID:16597996

Tal, Yossi; Watts, Joy E. M.; Schreier, Harold J.

2006-01-01

178

Phosphatase activity and specific methanogenic activity in an anaerobic reactor treating sludge from a brackish recirculation aquaculture system.  

PubMed

Anaerobic treatment of high salinity sludge from marine/brackish recirculation aquaculture systems is potentially limited by inhibition of enzymatic activities and cell lysis resulting from high osmotic pressures. To further address these limitations the following investigations were conducted: effect of salinity on phosphatase activity (PA), soluble microbial products (SMP) production, and presence of extracellular polymeric substances (EPS); effect of iron (III) chloride (FeCl3) on PA and specific methanogenic activity (SMA); effect of addition of the compatible solute glycine betaine (GB) and potassium on PA, as well as on SMP and EPS production, all under saline conditions. The results show that salinity has different effects on PA of anaerobes under starvation and feeding conditions. FeCl3 increased the SMA of the sludge by 22.5% at 100 mg FeCl3/L compared with a control group (0 mg FeCl3/L). Furthermore, results of analysis of variance tests show that betaine increased the polysaccharide content of EPS and polypeptide content of SMP. However, addition of 1 mM potassium chloride did not show a significant effect on EPS and SMP composition. In conclusion, anaerobic digestion of salty sludges from a brackish aquaculture recirculation system may not be negatively affected by FeCl3 addition to concentrate waste streams, whereas GB boosts the production of SMP and EPS. PMID:23863432

Zhang, Xuedong; Ferreira, Rui B; Spanjers, Henri; van Lier, Jules B

2013-01-01

179

Effect of the molecular adsorbent recirculating system and Prometheus devices on systemic haemodynamics and vasoactive agents in patients with acute-on-chronic alcoholic liver failure  

Microsoft Academic Search

INTRODUCTION: Patients with acute-on-chronic liver failure show an aggravated hyperdynamic circulation. We evaluated, in a controlled manner, potential changes in systemic haemodynamics induced by the molecular adsorbent recirculating system (MARS) and the Prometheus system liver detoxification devices in a group of patients with acute-on-chronic liver failure. METHODS: Eighteen patients (51.2 ± 2.3 years old; Child–Pugh score, 12.5 ± 0.2; Maddrey

Wim Laleman; Alexander Wilmer; Pieter Evenepoel; Ingrid Vander Elst; Marcel Zeegers; Zahur Zaman; Chris Verslype; Johan Fevery; Frederik Nevens

2006-01-01

180

Optimum design of cooling water systems for energy and water conservation  

Microsoft Academic Search

Re-circulating cooling water systems (RCWSs) are widely used to reject waste process heat to the environment, conserve fresh water and reduce thermal pollution relative to once-through systems. Research on RCWS has mostly focused on individual components, cooling tower and heat-exchanger network. Kim and Smith [Kim, J.K. and Smith, R., 2001, Cooling water system design, Chem Eng Sci, 56(12): 3641–3658] developed

M. H. Panjeshahi; A. Ataei; M. Gharaie; R. Parand

2009-01-01

181

Impact of depuration of earthy-musty off-flavors on fillet quality of Atlantic salmon, Salmo salar, cultured in a recirculating system  

Technology Transfer Automated Retrieval System (TEKTRAN)

Over the past decade in the United States, there has been increased interest in the establishment and use of land-based, closed-containment systems [e.g., recirculating aquaculture system (RAS)] for salmonid culture. These culture systems have unique challenges compared to net pen culture of salmon...

182

Exhaust gas recirculation control  

SciTech Connect

In an internal combustion engine, recirculation of exhaust gases is controlled to maintain the control pressure in a zone of the recirculation passage proportional to a reference pressure and thus to provide exhaust gas recirculation as a proportion of induction air flow. A duty cycle modulated valve controls an exhaust backpressure port and an atmospheric pressure port to create the reference pressure, whereby the proportion of exhaust gases recirculated is established by the duty cycle and is independent of the induction air flow.

Stoltman, D.D.

1983-08-23

183

Exhaust gas recirculation control  

Microsoft Academic Search

In an internal combustion engine, recirculation of exhaust gases is controlled to maintain the control pressure in a zone of the recirculation passage proportional to a reference pressure and thus to provide exhaust gas recirculation as a proportion of induction air flow. A duty cycle modulated valve controls an exhaust backpressure port and an atmospheric pressure port to create the

Stoltman

1983-01-01

184

Exhaust gas recirculation control  

Microsoft Academic Search

A transducer creates an operating pressure that positions a control valve to provide exhaust gas recirculation at rates which maintain the control pressure in the recirculation passage between the valve and an orifice equal to a reference pressure; exhaust gas recirculation thus varies with engine exhaust backpressure and accordingly is substantially proportional to induction air flow. The transducer also varies

Vogelsberg

1979-01-01

185

Exhaust gas recirculation control  

Microsoft Academic Search

A regulating unit senses the pressures in two zones of a recirculation passage to create a control pressure, and a transducer regulates an operating pressure which positions a control valve to provide exhaust gas recirculation at rates which establish the pressures in the zones necessary to maintain the control pressure equal to a reference pressure. Exhaust gas recirculation thus varies

Stoltman

1980-01-01

186

Role of Hot Water System Design on Factors Influential to Pathogen Regrowth: Temperature, Chlorine Residual, Hydrogen Evolution, and Sediment  

PubMed Central

Abstract Residential water heating is linked to growth of pathogens in premise plumbing, which is the primary source of waterborne disease in the United States. Temperature and disinfectant residual are critical factors controlling increased concentration of pathogens, but understanding of how each factor varies in different water heater configurations is lacking. A direct comparative study of electric water heater systems was conducted to evaluate temporal variations in temperature and water quality parameters including dissolved oxygen levels, hydrogen evolution, total and soluble metal concentrations, and disinfectant decay. Recirculation tanks had much greater volumes of water at temperature ranges with potential for increased pathogen growth when set at 49°C compared with standard tank systems without recirculation. In contrast, when set at the higher end of acceptable ranges (i.e., 60°C), this relationship was reversed and recirculation systems had less volume of water at risk for pathogen growth compared with conventional systems. Recirculation tanks also tended to have much lower levels of disinfectant residual (standard systems had 40–600% higher residual), 4–6 times as much hydrogen, and 3–20 times more sediment compared with standard tanks without recirculation. On demand tankless systems had very small volumes of water at risk and relatively high levels of disinfectant residual. Recirculation systems may have distinct advantages in controlling pathogens via thermal disinfection if set at 60°C, but these systems have lower levels of disinfectant residual and greater volumes at risk if set at lower temperatures. PMID:24170969

Brazeau, Randi H.; Edwards, Marc A.

2013-01-01

187

Comparative performance of CO2 measuring methods: marine aquaculture recirculation system application  

USGS Publications Warehouse

Many methods are available for the measurement of dissolved carbon dioxide in an aqueous environment. Standard titration is the typical field method for measuring dissolved CO2 in aquaculture systems. However, titrimetric determination of dissolved CO2 in marine water aquaculture systems is unsuitable because of the high dissolved solids, silicates, and other dissolved minerals that interfere with the determination. Other methods used to measure dissolved carbon dioxide in an aquaculture water included use of a wetted CO2 probe analyzer, standard nomographic methods, and calculation by direct measurements of the water's pH, temperature, and alkalinity. The determination of dissolved CO2 in saltwater based on partial pressure measurements and non-dispersive infra-red (NDIR) techniques with a CO2 gas analyzer are widely employed for oceanic surveys of surface ocean CO2 flux and are similar to the techniques employed with the head space unit (HSU) in this study. Dissolved carbon dioxide (DC) determination with the HSU using a infra-red gas analyzer (IRGA) was compared with titrimetric, nomographic, calculated, and probe measurements of CO2 in freshwater and in saltwater with a salinity ranging from 5.0 to 30 ppt, and a CO2 range from 8 to 50 mg/L. Differences in CO2 measurements between duplicate HSUs (0.1–0.2 mg/L) were not statistically significant different. The coefficient of variation for the HSU readings averaged 1.85% which was better than the CO2 probe (4.09%) and that for the titrimetric method (5.84%). In all low, medium and high salinity level trials HSU precision was good, averaging 3.39%. Differences existed between comparison testing of the CO2 probe and HSU measurements with the CO2 probe readings, on average, providing DC estimates that were higher than HSU estimates. Differences between HSU and titration based estimates of DC increased with salinity and reached a maximum at 32.2 ppt. These differences were statistically significant (P < 0.05) at all salinity levels greater than 0.3 ppt. Results indicated reliable replicated results from the head space unit with varying salinity and dissolved carbon dioxide concentrations.

Pfeiffer, T.J.; Summerfelt, S.T.; Watten, B.J.

2011-01-01

188

Exhaust gas recirculation control  

SciTech Connect

A regulating unit senses the pressures in two zones of a recirculation passage to create a control pressure, and a transducer regulates an operating pressure which positions a control valve to provide exhaust gas recirculation at rates which establish the pressures in the zones necessary to maintain the control pressure equal to a reference pressure. Exhaust gas recirculation thus varies with engine exhaust backpressure and accordingly is a proportion of induction air flow with the proportion being ruled by the regulating unit.

Stoltman, D.D.

1980-04-08

189

Comparison of a fuel-driven and steam-driven ejector in solid oxide fuel cell systems with anode off-gas recirculation: Part-load behavior  

NASA Astrophysics Data System (ADS)

This paper investigates the use of ejectors for recirculating anode off-gas in an SOFC system, focusing on the part-load capability of two different systems. In the first system, recirculation was enabled by a fuel-driven ejector. The part-load threshold of this system was determined by carbon formation and was 77.8% assuming a fuel utilization of 70% and suitable ejector geometry. The second system was based on a steam-driven ejector. The simulation results for this system showed an improved part-load capability of 37.8% as well as a slightly improved electrical efficiency. Here, the minimal part load was determined by the condensation temperature of the condenser used in the system.

Engelbracht, Maximilian; Peters, Roland; Blum, Ludger; Stolten, Detlef

2015-03-01

190

Water Systems  

NSDL National Science Digital Library

Water cycle concepts and basics including the distribution of water on the planet in oceans, rivers and lakes, glaciers and atmosphere. Defines basic terms: states of water, evaporation, transpiration, condensation, precipitation, melting. Good illustrations, maps and photos. Excellent list itemizes human uses and impacts on water and the water cycle. Links to more detailed references are provided, case studies illustrate current concerns and issues in Ontario, Canada.

191

Association of Mycobacteria in Recirculating Aquaculture Systems and Mycobacterial Disease in Fish  

E-print Network

, to their resistance to disinfectants (Taylor et al. 2000) and ability to grow in potable waters of low organic matter­2% NaCl) waters (George et al. 1980) allow these slowly growing bacteria to persist and grow in pipes

Watson, Craig A.

192

Exhaust gas recirculation control  

Microsoft Academic Search

A switching member simultaneously establishes a reference pressure and selects the pressure in one of two zones of a recirculation passage to create a control pressure, and a transducer regulates an operating pressure which positions a control valve to provide exhaust gas recirculation at rates which establish the pressures in the zones necessary to maintain the control pressure equal to

R. J. Haka; D. D. Stoltman

1980-01-01

193

Inland marine fish culture in low-salinity recirculating aquaculture systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

Expansion of marine aquaculture is challenged by the high cost and limited availability of coastal land and water resources, effluent concerns, high production costs, restricted growing seasons, lack of quality seedstock, and inadequate regulatory and permitting processes. Many of these constraints...

194

Exhaust gas recirculation control  

SciTech Connect

A switching member simultaneously establishes a reference pressure and selects the pressure in one of two zones of a recirculation passage to create a control pressure, and a transducer regulates an operating pressure which positions a control valve to provide exhaust gas recirculation at rates which establish the pressures in the zones necessary to maintain the control pressure equal to the reference pressure. Exhaust gas recirculation thus varies with engine exhaust backpressure and accordingly is a proportion of induction air flow with the proportion being ruled by the switching member.

Haka, R. J.; Stoltman, D. D.

1980-02-05

195

Performance of the seaweeds Gracilaria salicornia and Caulerpa lentillifera as biofilters in a hatchery scale recirculating aquaculture system for juvenile spotted babylons ( Babylonia areolata )  

Microsoft Academic Search

This study was conducted to determine the feasibility of using seaweeds as biofilters in a hatchery scale recirculating aquaculture\\u000a system for juvenile spotted babylons (Babylonia areolata). Two seaweeds Gracilaria salicornia and Caulerpa lentillifera were used with three initial biomass levels of each species (280, 560 and 840 g wet weight m?3). Spotted babylon with an average initial shell length of 1.32 ± 0.01 cm and body weight

Nilnaj Chaitanawisuti; Wannanee Santhaweesuk; Sirusa Kritsanapuntu

196

Development of zooplankton culture subsystem for a closed ecological recirculating aquaculture system (CERAS)  

NASA Astrophysics Data System (ADS)

Ten parthenogenetic females of Moina macrocopa were placed in small cells with different flow conditions. The cells were opened after three-days of cultivation, and the water fleas in each cell were counted. It appeared that M. macrocopa were cultured effectively in a relatively slow current, 10 cm/min., but the population growth was not significantly influenced by the difference in flow direction. Subsequent, filtration efficiencies of filters with various pore sizes were compared. Four available porous hollow-fiber membrane modules, ACP-1010, AHP-1010, PSP-103, and PMP-102 (Asahi-Kasei Corp.), were tested. The module with the larger pore size initially filtered a greater amount of water but clogged up sooner. ACP-1010, which has the smallest pores, was considered to be suitable to filter condensed algal water due to its durability and stable filtration. An improved zooplankton culture device (IZCD) was designed and constructed based on these examinations. IZCD is a 13.2L airtight device characterized by a short and thick rearing tank and alternate filtration with paired fine hollow-fiber membrane modules. It must be tested and revised to be used in research into the optimal conditions for a zooplankton culture in a closed environment.

Omori, Katsunori; Oguchi, Mitsuo; Takeuchi, Toshio

2006-01-01

197

Effects of non-uniform root zone salinity on water use, Na+ recirculation, and Na+ and H+ flux in cotton  

PubMed Central

A new split-root system was established through grafting to study cotton response to non-uniform salinity. Each root half was treated with either uniform (100/100?mM) or non-uniform NaCl concentrations (0/200 and 50/150?mM). In contrast to uniform control, non-uniform salinity treatment improved plant growth and water use, with more water absorbed from the non- and low salinity side. Non-uniform treatments decreased Na+ concentrations in leaves. The [Na+] in the ‘0’ side roots of the 0/200 treatment was significantly higher than that in either side of the 0/0 control, but greatly decreased when the ‘0’ side phloem was girdled, suggesting that the increased [Na+] in the ‘0’ side roots was possibly due to transportation of foliar Na+ to roots through phloem. Plants under non-uniform salinity extruded more Na+ from the root than those under uniform salinity. Root Na+ efflux in the low salinity side was greatly enhanced by the higher salinity side. NaCl-induced Na+ efflux and H+ influx were inhibited by amiloride and sodium orthovanadate, suggesting that root Na+ extrusion was probably due to active Na+/H+ antiport across the plasma membrane. Improved plant growth under non-uniform salinity was thus attributed to increased water use, reduced leaf Na+ concentration, transport of excessive foliar Na+ to the low salinity side, and enhanced Na+ efflux from the low salinity root. PMID:22200663

Kong, Xiangqiang; Luo, Zhen; Dong, Hezhong; Eneji, A. Egrinya

2012-01-01

198

Recirculating rotary gas compressor  

DOEpatents

A positive displacement, recirculating Roots-type rotary gas compressor which operates on the basis of flow work compression. The compressor includes a pair of large diameter recirculation conduits (24 and 26) which return compressed discharge gas to the compressor housing (14), where it is mixed with low pressure inlet gas, thereby minimizing adiabatic heating of the gas. The compressor includes a pair of involutely lobed impellers (10 and 12) and an associated port configuration which together result in uninterrupted flow of recirculation gas. The large diameter recirculation conduits equalize gas flow velocities within the compressor and minimize gas flow losses. The compressor is particularly suited to applications requiring sustained operation at higher gas compression ratios than have previously been feasible with rotary pumps, and is particularly applicable to refrigeration or other applications requiring condensation of a vapor.

Weinbrecht, John F. (601 Oakwood Loop, NE., Albuquerque, NM 87123)

1992-01-01

199

Electron recirculation in electrostatic multicusp systems: 1. Confinement and losses in simple power law wells  

Microsoft Academic Search

A large body of work over the past 35 years has been devoted to the study of cusp confinement of electrons, ions, and plasmas. Nearly all of this has examined single particle electron (or ion) motion or the motion of particles in neutral plasmas within cusped magnetic systems, generally without internal electric potential fields. In this note the problem of

R. W. Bussard; K. E. King

1991-01-01

200

Root Media Materials for Cucumber Production in Closed Recirculated Hydroponic Systems  

Microsoft Academic Search

Cucumber (Cucumis sativus L. cv. Rawa) was grown in hydroponics .for two successive seasons under glasshouse conditions to test materials in the gullies of the nutrient film technique (NFT) system. Treatments were: date-palm fibers (Leef); dried shredded date-plam leaflets (Karena), nylon threads (NT); 3-inch- PVC pipes (pipe); rock wool (RW) and the control. The Leef and Karena treatments exceeded the

M. A. Medany; M. M. Hafez; A. F. Abou-Hadid; A. S. El-Beltagy

1995-01-01

201

Improvement of multiple organ functions in hepatorenal syndrome during albumin dialysis with the molecular adsorbent recirculating system.  

PubMed

Recently, significant improvement of renal function and prolongation of survival were reported in hepatorenal syndrome (HRS) patients treated with the Molecular Adsorbent Recirculating System (MARS). As no impact on extrarenal organ function was documented, this trial looked into multiple organ function changes during MARS in HRS patients. Eight HRS patients (4 male, mean age 42.1 years, range 30-58, all United Network for Organ Sharing [UNOS] status 2A) were treated intermittendly 4-14 times (total 47, mean 5.9 +/- 3.4) between 4 and 8 h/single treatment. The following changes were observed pre- and posttreatment: bilirubin 466 +/- 146 to 284 +/- 134 micromol/L, creatinine 380 +/- 182 to 163 +/- 119 micromol/L, urea 26.4 +/- 10.3 to 12.9 +/- 4.9 mmol/L, plasma sodium 127.5 +/- 7.7 to 137.5 +/- 4.8 mmol/L (all p < 0.01). Mean arterial pressure (MAP) increased from 71.9 +/- 12.8 to 95.6 +/- 7.8 Torr (p < 0.001). Oliguria or anuria, present in all patients, was successfully reverted. Ascites, present in all patients, was not detectable after the treatment period. The hepatic encephalopathy grade decreased from 2.8 +/- 0.8 to 0.8 +/- 0.7 (p < 0.0001). Child-Index decreased from 13.25 +/- 1.3 to 9.4 +/- 1.8 (p < 0.001). The hospital survival rate was 62%. One man underwent successful liver transplantation 18 months after the treatment. We conclude that MARS can improve multiple organ functions in patients with HRS. PMID:11778928

Mitzner, S R; Klammt, S; Peszynski, P; Hickstein, H; Korten, G; Stange, J; Schmidt, R

2001-10-01

202

Systems and methods for reactive distillation with recirculation of light components  

DOEpatents

Systems and methods for producing gas-to-liquids products using reactive distillation are provided. The method for producing gas-to-liquids products can include reacting a feedstock in a column having a distillation zone and a reaction zone to provide a bottoms stream and an overhead stream. A first portion of the overhead stream can be recycled to the column at the top of the reaction zone and second portion of the overhead stream can be recycled to the column at the bottom of the reaction zone.

Stickney, Michael J. (Nassau Bay, TX); Jones, Jr., Edward M. (Friendswood, TX)

2011-07-26

203

Relevance of Nitrospira for nitrite oxidation in a marine recirculation aquaculture system and physiological features of a Nitrospira marina-like isolate.  

PubMed

In biofilters of recirculation aquaculture systems (RAS), nitrification by lithoautotrophic microorganisms is essential to prevent the cultivated organisms from intoxication with ammonium and nitrite. In moving-bed biofilters nitrifying microorganisms are immobilized together with heterotrophic bacteria in dense biofilms on carrier elements like plastic beads. Analyses of fatty acid profiles of these biofilms from a marine biofilter revealed a high abundance of Nitrospira-related lipid markers (8-12% of total fatty acids). Further results of a labeling experiment with (13) C-bicarbonate in mineral salts medium with 3 mM nitrite confirmed that Nitrospira is the major autotrophic nitrite oxidizer in the biofilter system. According to 16S rRNA gene sequence analyses the nitrite-oxidizing community in the biofilter consisted of at least two different representatives of Nitrospira, one of which could be successfully isolated. The marine isolate 'Ecomares 2.1' belongs to cluster IVa and showed 98.8% 16S rRNA gene sequence similarity to Nitrospira marina, whereas the enrichment 'M1 marine' is only distantly related (94.0% 16S rRNA gene sequence similarity to N. marina). In laboratory experiments, the isolate exhibited remarkable tolerances against high substrate and product concentrations (30 mM nitrite and 80 mM nitrate) as well as ammonium (50 mM). During the isolation process a strong tendency of this strain to develop biofilms became apparent. Thus, Ecomares 2.1 seems to be well adapted to the attached lifestyle in biofilters and the nitrogenous load prevailing in the effluent waters of RAS. Both members of Nitrospira could be detected by PCR-based methods in environmental samples of marine and brackish RAS biofilters and are therefore considered to be characteristic for these engineered ecosystems. PMID:21812886

Keuter, Sabine; Kruse, Myriam; Lipski, André; Spieck, Eva

2011-09-01

204

Containment system for supercritical water oxidation reactor  

DOEpatents

A system for containment of a supercritical water oxidation reactor in the event of a rupture of the reactor. The system includes a containment for housing the reaction vessel and a communicating chamber for holding a volume of coolant, such as water. The coolant is recirculated and sprayed to entrain and cool any reactants that might have escaped from the reaction vessel. Baffles at the entrance to the chamber prevent the sprayed coolant from contacting the reaction vessel. An impact-absorbing layer is positioned between the vessel and the containment to at least partially absorb momentum of any fragments propelled by the rupturing vessel. Remote, quick-disconnecting fittings exterior to the containment, in cooperation with shut-off valves, enable the vessel to be isolated and the system safely taken off-line. Normally-closed orifices throughout the containment and chamber enable decontamination of interior surfaces when necessary.

Chastagner, Philippe (3134 Natalie Cir., Augusta, GA 30909-2748)

1994-01-01

205

Containment system for supercritical water oxidation reactor  

DOEpatents

A system is described for containment of a supercritical water oxidation reactor in the event of a rupture of the reactor. The system includes a containment for housing the reaction vessel and a communicating chamber for holding a volume of coolant, such as water. The coolant is recirculated and sprayed to entrain and cool any reactants that might have escaped from the reaction vessel. Baffles at the entrance to the chamber prevent the sprayed coolant from contacting the reaction vessel. An impact-absorbing layer is positioned between the vessel and the containment to at least partially absorb momentum of any fragments propelled by the rupturing vessel. Remote, quick-disconnecting fittings exterior to the containment, in cooperation with shut-off valves, enable the vessel to be isolated and the system safely taken off-line. Normally-closed orifices throughout the containment and chamber enable decontamination of interior surfaces when necessary. 2 figures.

Chastagner, P.

1994-07-05

206

Estimated Costs and Returns for Catfish Farms with Recirculating Ponds Along the Upper Texas Coast.  

E-print Network

. The paddle wheels are included in the analysis as a risk reduction measure. I Aside from the paddle wheels, substantial aeration and mixing are provided by the recirculating water in each system. All farms are supplied with equipment to distrib LIte... of the recirculating system. Each pond is equipped with a 7.46 kW (10 hp) electric paddle wheel. During the summer growing season, all ponds are monitored daily for dissolved oxygen deficiency dur ?ng the early morning hours. CATSIM applies aeration if pond...

Lambregts, J.A.D.; Griffin, W.L.; Lacewell R.D.; Davis, J.T.; Clary, G.M.

1992-01-01

207

Na+ recirculation and isosmotic transport.  

PubMed

The Na(+) recirculation theory for solute-coupled fluid absorption is an expansion of the local osmosis concept introduced by Curran and analyzed by Diamond & Bossert. Based on studies on small intestine the theory assumes that the observed recirculation of Na(+) serves regulation of the osmolarity of the absorbate. Mathematical modeling reproducing bioelectric and hydrosmotic properties of small intestine and proximal tubule, respectively, predicts a significant range of observations such as isosmotic transport, hyposmotic transport, solvent drag, anomalous solvent drag, the residual hydraulic permeability in proximal tubule of AQP1 (-/-) mice, and the inverse relationship between hydraulic permeability and the concentration difference needed to reverse transepithelial water flow. The model reproduces the volume responses of cells and lateral intercellular space (lis) following replacement of luminal NaCl by sucrose as well as the linear dependence of volume absorption on luminal NaCl concentration. Analysis of solvent drag on Na(+) in tight junctions provides explanation for the surprisingly high metabolic efficiency of Na(+) reabsorption. The model predicts and explains low metabolic efficiency in diluted external baths. Hyperosmolarity of lis is governed by the hydraulic permeability of the apical plasma membrane and tight junction with 6-7 mOsm in small intestine and < or = 1 mOsm in proximal tubule. Truly isosmotic transport demands a Na(+) recirculation of 50-70% in small intestine but might be barely measurable in proximal tubule. The model fails to reproduce a certain type of observations: The reduced volume absorption at transepithelial osmotic equilibrium in AQP1 knockout mice, and the stimulated water absorption by gallbladder in diluted external solutions. Thus, it indicates cellular regulation of apical Na(+) uptake, which is not included in the mathematical treatment. PMID:17206513

Larsen, E H; Møbjerg, N

2006-01-01

208

Energy conservation by partial recirculation of peanut drying air  

SciTech Connect

Conventional, recirculating, and intermittent type peanut dryers were compared in a three-year study. Comparisons indicate that partial recirculation of peanut drying air may reduce energy consumption per unit of water removed by approximately 25% while also reducing required drying time and maintaining high quality.

Young, J.H.

1983-06-01

209

Toluene removal in membrane bioreactors under recirculating and non-recirculating liquid conditions  

Microsoft Academic Search

A single-, dual- and multiple-tube dense phase silicone rubber membrane bioreactor were investigated for control of toluene-contaminated\\u000a air under circulating and non-recirculating liquid conditions. A mathematical model was developed to describe the system.\\u000a The reactors were seeded with a mixed bacterial consortium isolated from activated sludge and capable of aromatic biodegradation.\\u000a After operating with recirculating liquid nutrient solution, the reactors

Ellen England; Mark W. Fitch; Melanie Mormile; Michael Roberts

2005-01-01

210

Biodiversity of N-cycle bacteria in nitrogen removing moving bed biofilters for freshwater recirculating aquaculture systems  

Microsoft Academic Search

Maintenance of optimal water quality and removal of nitrogen compounds pose challenges to aquaculture worldwide. Presence and activity of different bacteria involved in nitrogen cycling in the biofilm of a moving bed biofilm reactor (MBBR) connected to a Koi carp tank were investigated experimentally. For this MBBR system, a nitrogen removing rate of 3.5g nitrogen per day was found in

Maartje A. H. J. van Kessel; Harry R. Harhangi; Katinka van de Pas-Schoonen; J. L. C. M. van de Vossenberg; Gert Flik; Mike S. M. Jetten; Peter H. M. Klaren

2010-01-01

211

Wash water recovery system  

NASA Technical Reports Server (NTRS)

The Wash Water Recovery System (WWRS) is intended for use in processing shower bath water onboard a spacecraft. The WWRS utilizes flash evaporation, vapor compression, and pyrolytic reaction to process the wash water to allow recovery of potable water. Wash water flashing and foaming characteristics, are evaluated physical properties, of concentrated wash water are determined, and a long term feasibility study on the system is performed. In addition, a computer analysis of the system and a detail design of a 10 lb/hr vortex-type water vapor compressor were completed. The computer analysis also sized remaining system components on the basis of the new vortex compressor design.

Deckman, G.; Rousseau, J. (editor)

1973-01-01

212

Effect of Water pH on Yield and Nutritional Status of Greenhouse Cucumber Grown in Recirculating Hydroponics  

Microsoft Academic Search

Cucumbers are produced in integrated hydroponic and aquaculture systems (aquaponics). Aquaponics balances pH for plants, fish, and nitrifying bacteria. Nitrification prevents buildup of toxic waste ammonia by conversion to nitrate (NO3 - nitrogen (N). The pH for hydroponic cucumbers (5.5–6.0) and nitrification (7.5–9.0) requires reconciliation to improve systems integration. Cucumbers were grown at pH of 5.0, 6.0, 7.0, and 8.0

R. V. Tyson; E. H. Simonne; D. D. Treadwell; M. Davis; J. M. White

2008-01-01

213

Economic values of growth and feed efficiency for fish farming in recirculating aquaculture system with density and nitrogen output limitations: a case study with African catfish (Clarias gariepinus).  

PubMed

In fish farming, economic values (EV) of breeding goal traits are lacking, even though they are key parameters when defining selection objectives. The aim of this study was to develop a bioeconomic model to estimate EV of 2 traits representing production performances in fish farming: the thermal growth coefficient (TGC) and the feed conversion ratio (FCR). This approach was applied to a farm producing African catfish (Clarias gariepinus) in a recirculating aquaculture system (RAS). In the RAS, 2 factors could limit production level: the nitrogen treatment capacity of the biofilter or the fish density in rearing tanks at harvest. Profit calculation includes revenue from fish sales, cost of juveniles, cost of feed, cost of waste water treatment, and fixed costs. In the reference scenario, profit was modeled to zero. EV were calculated as the difference in profit per kilogram of fish between the current population mean for both traits (µt) and the next generation of selective breeding (µt + ?t) for either TGC or FCR. EV of TGC and FCR were calculated for three generations of hypothetical selection on either TGC or FCR (respectively 6.8% and 7.6% improvement per generation). The results show that changes in TGC and FCR can affect both the number of fish that can be stocked (number of batches per year and number of fish per batch) and the factor limiting production. The EV of TGC and FCR vary and depend on the limiting factors. When dissolved NH3-N is the limiting factor for both µt and µt + ?t, increasing TGC decreases the number of fish that can be stocked but increases the number of batches that can be grown. As a result, profit remains constant and EVTGC is zero. Increasing FCR, however, increases the number of fish stocked and the ratio of fish produced per kilogram of feed consumed ("economic efficiency"). The EVFCR is 0.14 €/kg of fish, and profit per kilogram of fish increases by about 10%. When density is the limiting factor for both µt and µt + ?t, the number of fish stocked per batch is fixed; therefore, extra profit is obtained by increasing either TGC, which increases the annual number of batches, or by decreasing FCR, which decreases annual feed consumption. EVTGC is 0.03 €/kg of fish and EVFCR is 0.05-0.06 €/kg of fish. These results emphasize the importance of calculating economic values in the right context to develop efficient future breeding programs in aquaculture. PMID:25414104

Besson, M; Komen, H; Aubin, J; de Boer, I J M; Poelman, M; Quillet, E; Vancoillie, C; Vandeputte, M; van Arendonk, J A M

2014-12-01

214

Performance Evaluation of Hot Water Efficiency Plumbing System Using Thermal Valve  

E-print Network

hot water piping system, Thermo controlled valve, Circulation, Mixing water pipe, Recirculation water pipe INTRODUCTION Finding ways to conserve energy while heating a building?s water supply can be approached from a number of angles. Still...?s disadvantage is that so much water is wasted until the optimal tap temperature is reached.(6) We tried to solve this problem by developing a water-saving hot water plumbing system that utilizes a thermo-controlled valve. The goal was to not allow...

Cha, K. S.; Park, M. S.; Seo, H. Y.

215

The Role of Water Chemistry in Marine Aquarium Design: A Model System for a General Chemistry Class  

ERIC Educational Resources Information Center

Water chemistry is central to aquarium design, and it provides many potential applications for discussion in undergraduate chemistry and engineering courses. Marine aquaria and their life support systems feature many chemical processes. A life support system consists of the entire recirculation system, as well as the habitat tank and all ancillary…

Keaffaber, Jeffrey J.; Palma, Ramiro; Williams, Kathryn R.

2008-01-01

216

Effect of hydraulic loading rate on the efficiency of effluent treatment in a recirculating puffer aquaculture system coupled with constructed wetlands  

NASA Astrophysics Data System (ADS)

Constructed wetlands (CWs) were integrated into an indoor recirculating aquaculture system of obscure puffer (Takifugu obscurus) for effluent treatment. The effect of hydraulic loading rate (HLR) on the efficiency of effluent treatment by CWs was examined for over a month. The CWs were operated under brackish conditions (salinity 7.4-7.6) at 3 different HLRs (0.762, 0.633, and 0.458 m d-1) 3 times, 10 days each. Overall, the CWs exhibited high efficiency in removal of total ammonium nitrogen (by 81.03-92.81%) and nitrite nitrogen (by 99.40%-99.68%). The efficiency of CWs in removal of total ammonium nitrogen, nitrate nitrogen, total Kjeldahl nitrogen, total phosphorous, and total suspended solids (TSS) increased with the decrease of HLR. The CWs operated at the 3 HLRs in a decreasing trend proves to be effective, providing a useful method for effluent treatment in commercial puffer aquaculture systems.

Xu, Jiabo; Shi, Yonghai; Zhang, Genyu; Liu, Jianzhong; Zhu, Yazhu

2013-11-01

217

DESIGN CHARACTERISTICS OF THE USDA/ARS-HBOI SUSTAINABLE TANK AQUACULTURE RECIRCULATING RESEARCH (STARR) FACILITY FOR LOW-SALINITY FINFISH PRODUCTION  

Technology Transfer Automated Retrieval System (TEKTRAN)

Water treatment components of a recirculating aquaculture system (RAS) consist mainly of: solid removal devices, biofiltration, aeration and degassing units, and water distribution mechanisms. For each component, multiple options are available and the selection is based on system volume and hydrodyn...

218

Options for transpiration water removal in a crop growth system under zero gravity conditions  

NASA Technical Reports Server (NTRS)

The operation of a microgravity crop-growth system is a critical feature of NASA's Closed Ecological Life Support System (CELSS) development program. Transpiration-evolved water must be removed from the air that is recirculated in such a system, perhaps supplying potable water in the process. The present consideration of candidate systems for CELSS water removal gives attention to energy considerations and to a mechanical, inertial-operation water-separation system that was chosen due to the depth of current understanding of its operation.

Blackwell, C. C.; Kliss, M.; Yendler, B.; Borchers, B.; Yendler, Boris S.; Nguyen, Thoi K.; Waleh, Ahmad

1991-01-01

219

Recirculating Air Filtration Significantly Reduces Exposure to Airborne Nanoparticles  

PubMed Central

Background Airborne nanoparticles from vehicle emissions have been associated with adverse effects in people with pulmonary and cardiovascular disease, and toxicologic studies have shown that nanoparticles can be more hazardous than their larger-scale counterparts. Recirculating air filtration in automobiles and houses may provide a low-cost solution to reducing exposures in many cases, thus reducing possible health risks. Objectives We investigated the effectiveness of recirculating air filtration on reducing exposure to incidental and intentionally produced airborne nanoparticles under two scenarios while driving in traffic, and while generating nanomaterials using gas-phase synthesis. Methods We tested the recirculating air filtration in two commercial vehicles when driving in traffic, as well as in a nonventilation room with a nanoparticle generator, simulating a nanomaterial production facility. We also measured the time-resolved aerosol size distribution during the in-car recirculation to investigate how recirculating air filtration affects particles of different sizes. We developed a recirculation model to describe the aerosol concentration change during recirculation. Results The use of inexpensive, low-efficiency filters in recirculation systems is shown to reduce nanoparticle concentrations to below levels found in a typical office within 3 min while driving through heavy traffic, and within 20 min in a simulated nanomaterial production facility. Conclusions Development and application of this technology could lead to significant reductions in airborne nanoparticle exposure, reducing possible risks to health and providing solutions for generating nanomaterials safely. PMID:18629306

Pui, David Y.H.; Qi, Chaolong; Stanley, Nick; Oberdörster, Günter; Maynard, Andrew

2008-01-01

220

Water Purification Systems  

NASA Technical Reports Server (NTRS)

A water purification/recycling system developed by Photo-Catalytics, Inc. (PCI) for NASA is commercially available. The system cleanses and recycles water, using a "photo-catalysis" process in which light or radiant energy sparks a chemical reaction. Chemically stable semiconductor powders are added to organically polluted water. The powder absorbs ultraviolet light, and pollutants are oxidized and converted to carbon dioxide. Potential markets for the system include research and pharmaceutical manufacturing applications, as well as microchip manufacture and wastewater cleansing.

1992-01-01

221

Recirculation-aeration: Bibliography for aquaculture. Bibliographies and literature of agriculture (Final)  

Microsoft Academic Search

The bibliography includes literature citations through 1992 related to water recirculation and aeration in aquaculture. The focus is on filtration, aeration, and circulation techniques in various aquaculture situations.

P. W. Perschbacher; R. V. Powell; D. W. Freeman; W. J. Lorio; D. T. Hanfman

1993-01-01

222

Recirculation-aeration: Bibliography for aquaculture. Bibliographies and literature of agriculture (Final)  

SciTech Connect

The bibliography includes literature citations through 1992 related to water recirculation and aeration in aquaculture. The focus is on filtration, aeration, and circulation techniques in various aquaculture situations.

Perschbacher, P.W.; Powell, R.V.; Freeman, D.W.; Lorio, W.J.; Hanfman, D.T.

1993-08-01

223

Feasible use of rock oyster (Crassostrea commercialis) and seaweeds (Gracilaria salicornia and Caulerpa lentillife) as biofilter in a laboratory - scale closed recirculating system for juveniles spotted babylon (Babylonia areolata)  

Microsoft Academic Search

This study was conducted to assess the feasible use of rock oyster (Crassostrea commercialis) in biofiltration and two seaweeds (Gracilaria salicornia and Caulerpa lentillife) as nutrient absorbant in a laboratory - scale recirculating system for growing of juveniles spotted babylon (Babylonia areolata). The experiment was carried out in triplicates over a period of 90 days. The experiment was a complete

Nilnaj Chaitanawisuti; Wannanee Santhaweesuk; Sirusa Kritsanapuntu; Phya Thai

2011-01-01

224

Mineral nutrient concentration and uptake by tomato irrigated with recirculating aquaculture water as influenced by quantity of fish waste products supplied  

Microsoft Academic Search

Fish and tomato (Lycopersicon esculentum Mill.) production were linked in a recirculaing water system. Fish (tilapia) were fed a commercial diet with 32% protein. Tomato cultivars ‘Laura’ and ‘Kewalo’ were grown during summer 1988 and spring 1989, respectively, in a Raleigh, NC greenhouse. Plants were grown in biofilters at 4 plants\\/m and surface irrigated 8 times daily with water pumped

M. R. McMurtry; D. C. Sanders; P. V. Nelson; A. Nash

1993-01-01

225

Automatic water heater systems  

SciTech Connect

A heat trap is described which can be connected to the flue exhaust outlet of an automatic gas water heating system in which heat can be entrapped that would otherwise be lost via hot flue gases passing up through the flue exhaust and out of a chimney. The heat trap comprises a tank containing therein vertically extending serpentine heat tubes. The lower ends of the heat tubes are connected to a common exhaust inlet which is directly fastened to the exhaust outlet of the automatic gas water heating system. The upper end of the heat tubes are connected to an exhaust outlet of the heat trap which is connected to the chimney. The heat trap also comprises a cold water inlet and a heated water outlet which connects to the cold water inlet of the automatic gas water heating system. The heat trap maintains a separate water supply in the heat trap tank to be delivered through the cold water inlet of the automatic gas water heating system as water is required to replenish water supply of the system.

Wilhelm, R.O. Jr.

1987-03-31

226

Reactor water cleanup system  

DOEpatents

A reactor water cleanup system includes a reactor pressure vessel containing a reactor core submerged in reactor water. First and second parallel cleanup trains are provided for extracting portions of the reactor water from the pressure vessel, cleaning the extracted water, and returning the cleaned water to the pressure vessel. Each of the cleanup trains includes a heat exchanger for cooling the reactor water, and a cleaner for cleaning the cooled reactor water. A return line is disposed between the cleaner and the pressure vessel for channeling the cleaned water thereto in a first mode of operation. A portion of the cooled water is bypassed around the cleaner during a second mode of operation and returned through the pressure vessel for shutdown cooling. 1 figure.

Gluntz, D.M.; Taft, W.E.

1994-12-20

227

Reactor water cleanup system  

DOEpatents

A reactor water cleanup system includes a reactor pressure vessel containing a reactor core submerged in reactor water. First and second parallel cleanup trains are provided for extracting portions of the reactor water from the pressure vessel, cleaning the extracted water, and returning the cleaned water to the pressure vessel. Each of the cleanup trains includes a heat exchanger for cooling the reactor water, and a cleaner for cleaning the cooled reactor water. A return line is disposed between the cleaner and the pressure vessel for channeling the cleaned water thereto in a first mode of operation. A portion of the cooled water is bypassed around the cleaner during a second mode of operation and returned through the pressure vessel for shutdown cooling.

Gluntz, Douglas M. (San Jose, CA); Taft, William E. (Los Gatos, CA)

1994-01-01

228

Purge water management system  

DOEpatents

A purge water management system is described for effectively eliminating the production of purge water when obtaining a groundwater sample from a monitoring well. In its preferred embodiment, the purge water management system comprises an expandable container, a transportation system, and a return system. The purge water management system is connected to a wellhead sampling configuration, typically permanently installed at the well site. A pump, positioned with the monitoring well, pumps groundwater through the transportation system into the expandable container, which expands in direct proportion with volume of groundwater introduced, usually three or four well volumes, yet prevents the groundwater from coming into contact with the oxygen in the air. After this quantity of groundwater has been removed from the well, a sample is taken from a sampling port, after which the groundwater in the expandable container can be returned to the monitoring well through the return system. The purge water management system prevents the purge water from coming in contact with the outside environment, especially oxygen, which might cause the constituents of the groundwater to oxidize. Therefore, by introducing the purge water back into the monitoring well, the necessity of dealing with the purge water as a hazardous waste under the Resource Conservation and Recovery Act is eliminated.

Cardoso-Neto, J.E.; Williams, D.W.

1995-01-01

229

Purge water management system  

DOEpatents

A purge water management system for effectively eliminating the production of purge water when obtaining a groundwater sample from a monitoring well. In its preferred embodiment, the purge water management system comprises an expandable container, a transportation system, and a return system. The purge water management system is connected to a wellhead sampling configuration, typically permanently installed at the well site. A pump, positioned with the monitoring well, pumps groundwater through the transportation system into the expandable container, which expands in direct proportion with volume of groundwater introduced, usually three or four well volumes, yet prevents the groundwater from coming into contact with the oxygen in the air. After this quantity of groundwater has been removed from the well, a sample is taken from a sampling port, after which the groundwater in the expandable container can be returned to the monitoring well through the return system. The purge water management system prevents the purge water from coming in contact with the outside environment, especially oxygen, which might cause the constituents of the groundwater to oxidize. Therefore, by introducing the purge water back into the monitoring well, the necessity of dealing with the purge water as a hazardous waste under the Resource Conservation and Recovery Act is eliminated.

Cardoso-Neto, Joao E. (North Augusta, SC); Williams, Daniel W. (Aiken, SC)

1996-01-01

230

SELECTED METABOLIC ASPECTS OF PIKEPERCH, STIZOSTEDION LUCIOPERCA (L.) REARED IN A WATER RECIRCULATION SYSTEM  

Microsoft Academic Search

The aim of the present study was to evaluate the effect of fish size (BW 11.7 g in the PS group, and 28.1 g in the PL group), feeding (SDA effect), and starvation (4, 13, 19 or 26 days in the PS-S group, and 4 or 13 days in the PL-S group) on oxygen consumption (OC ,m g O2 kg

Krystyna Demska-Zakêœ; Piotr Karczewski; Andrzej Karpiñski

231

Evaluating Domestic Hot Water Distribution System Options With Validated Analysis Models  

SciTech Connect

A developing body of work is forming that collects data on domestic hot water consumption, water use behaviors, and energy efficiency of various distribution systems. A full distribution system developed in TRNSYS has been validated using field monitoring data and then exercised in a number of climates to understand climate impact on performance. This study builds upon previous analysis modelling work to evaluate differing distribution systems and the sensitivities of water heating energy and water use efficiency to variations of climate, load, distribution type, insulation and compact plumbing practices. Overall 124 different TRNSYS models were simulated. Of the configurations evaluated, distribution losses account for 13-29% of the total water heating energy use and water use efficiency ranges from 11-22%. The base case, an uninsulated trunk and branch system sees the most improvement in energy consumption by insulating and locating the water heater central to all fixtures. Demand recirculation systems are not projected to provide significant energy savings and in some cases increase energy consumption. Water use is most efficient with demand recirculation systems, followed by the insulated trunk and branch system with a central water heater. Compact plumbing practices and insulation have the most impact on energy consumption (2-6% for insulation and 3-4% per 10 gallons of enclosed volume reduced). The results of this work are useful in informing future development of water heating best practices guides as well as more accurate (and simulation time efficient) distribution models for annual whole house simulation programs.

Weitzel, E.; Hoeschele, M.

2014-09-01

232

Water system virus detection  

NASA Technical Reports Server (NTRS)

The performance of a waste water reclamation system is monitored by introducing a non-pathogenic marker virus, bacteriophage F2, into the waste-water prior to treatment and, thereafter, testing the reclaimed water for the presence of the marker virus. A test sample is first concentrated by absorbing any marker virus onto a cellulose acetate filter in the presence of a trivalent cation at low pH and then flushing the filter with a limited quantity of a glycine buffer solution to desorb any marker virus present on the filter. Photo-optical detection of indirect passive immune agglutination by polystyrene beads indicates the performance of the water reclamation system in removing the marker virus. A closed system provides for concentrating any marker virus, initiating and monitoring the passive immune agglutination reaction, and then flushing the system to prepare for another sample.

Fraser, A. S.; Wells, A. F.; Tenoso, H. J. (inventors)

1978-01-01

233

Cooling Water System Optimization  

E-print Network

During summer months, many manufacturing plants have to cut back in rates because the cooling water system is not providing sufficient cooling to support higher production rates. There are many low/no-cost techniques available to improve tower...

Aegerter, R.

2005-01-01

234

The design, fabrication, operation and maintenance of D0 prototype 1/2 H. P. 170 S. C. F. H. gas recirculating-filtration-blending system  

SciTech Connect

Fermi National Accelerator Laboratory (Fermilab) D{null} collider, E-740, uses 150 proportional drift tube (P.D.T.) modules connected to a common multiple header to supply clean low pressure gas. A second multiple header returns the gas to the mixing area and exhausts it to the atmosphere. To test and debug the major construction problems associated with a large and long term experiment, a small cosmic ray test stand was constructed in the Wilson Hall ground floor Physics area. The first four P.D.T.'s that were constructed at FNAL's lab 5 Assembly area were installed in an 110 ton cosmic ray test stand. Two P.D.T.'s were installed above the double 50 ton magnet toroids and two were installed below. A prototype gas system was fabricated for the purpose of conducting development of a recirculating, filtering, and blending system for gas components as called upon by daily requirements set by the current needs of a collider experiment.

Sellberg, G.; Rapp, P.

1991-10-01

235

Coke-free dry reforming of model diesel fuel by a pulsed spark plasma at low temperatures using an exhaust gas recirculation (EGR) system  

NASA Astrophysics Data System (ADS)

Dry reforming of diesel fuel, an endothermic reaction, is an attractive process for on-board hydrogen/syngas production to increase energy efficiency. For operating this dry reforming process in a vehicle, we can use the exhaust gas from an exhaust gas recirculation (EGR) system as a source of carbon dioxide. Catalytic dry reforming of heavy hydrocarbon is a very difficult reaction due to the high accumulation of carbon on the catalyst. Therefore, we attempted to use a non-equilibrium pulsed plasma for the dry reforming of model diesel fuel without a catalyst. We investigated dry reforming of model diesel fuel (n-dodecane) with a low-energy pulsed spark plasma, which is a kind of non-equilibrium plasma at a low temperature of 523 K. Through the reaction, we were able to obtain syngas (hydrogen and carbon monoxide) and a small amount of C2 hydrocarbon without coke formation at a ratio of CO2/Cfuel = 1.5 or higher. The reaction can be conducted at very low temperatures such as 523 K. Therefore, it is anticipated as a novel and effective process for on-board syngas production from diesel fuel using an EGR system.

Sekine, Yasushi; Furukawa, Naotsugu; Matsukata, Masahiko; Kikuchi, Eiichi

2011-07-01

236

Optimal mixing in recirculation zones  

Microsoft Academic Search

Coarse-scale mixing in a recirculation zone is described with a simple vortex model. Time-dependent forcing is employed to change the vortex motion and mixing properties. An optimal mixing problem is defined in which the flux across the recirculation region shall be maximized under the side-constraints of bounded vortex motion and bounded actuation. Concepts of control theory and chaotic advection are

Bernd R. Noack; Igor Mezic; Gilead Tadmor; Andrzej Banaszuk

2004-01-01

237

Recirculation of municipal landfill leachate  

E-print Network

RECIRCULATION OF MUNICIPAL LANDFILL LEACHATE A Thesis by BRIAN JUDE PINKO4ISKI Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE May 1987 Major Subject...: Civil Engineering RECIRCULATION OF MUNICIPAL LANDFILL LEACHATE A Thesis by BRIAN JUDE PINKOWSKI Approved as to style and content by: Charles P. Giammona (Chair of Committee) Roy . Harm, (Member) Kirk W. Brown (Member) Donald A. Maxwel...

Pinkowski, Brian Jude

2012-06-07

238

Heat recirculating cooler for fluid stream pollutant removal  

DOEpatents

A process by which heat is removed from a reactant fluid to reach the operating temperature of a known pollutant removal method and said heat is recirculated to raise the temperature of the product fluid. The process can be utilized whenever an intermediate step reaction requires a lower reaction temperature than the prior and next steps. The benefits of a heat-recirculating cooler include the ability to use known pollutant removal methods and increased thermal efficiency of the system.

Richards, George A. (Morgantown, WV); Berry, David A. (Morgantown, WV)

2008-10-28

239

Application of chemical coagulation aids for the removal of suspended solids (TSS) and phosphorus from the microscreen effluent discharge of an intensive recirculating aquaculture system  

USGS Publications Warehouse

An evaluation of two commonly used coagulation-flocculation aids (alum and ferric chloride) was conducted to determine optimum conditions for treating the backwash effluent from microscreen filters in an intensive recirculating aquaculture system. Tests were carried out to evaluate the dosages and conditions (mixing and flocculation stirring speeds, durations, and settling times) required to achieve optimum waste capture. The orthophosphate removal efficiency for alum and ferric chloride were greater than 90% at a dosage of 60 mg/L. Optimum turbidity removal was achieved with a 60-mg/L dosage for both alum and ferric chloride. Both alum and ferric chloride demonstrated excellent removal of suspended solids from initial total suspended solid values of approximately 320 mg/L to approximately 10 mg/L at a dosage of 60 mg/L. Flocculation and mixing speed and duration played only a minor role in the removal efficiencies for both orthophosphates and suspended solids. Both coagulation-flocculation aids also exhibited excellent settling characteristics, with the majority of the floc quickly settling out in the first 5 min.

Ebeling, J.M.; Ogden, S.R.; Sibrell, P.L.; Rishel, K.L.

2004-01-01

240

Effects of spectral composition, photoperiod and light intensity on the gonadal development of Atlantic salmon Salmo salar in recirculating aquaculture systems (RAS)  

NASA Astrophysics Data System (ADS)

Artificial lighting regimes have been successfully used to inhibit sexual maturity of Atlantic salmon in confinement. However, when these operations are applied in commercial recirculating aquaculture systems (RAS) using standard lighting technology, sexual maturation is not suppressed. In this study, an L9 (33) orthogonal design was used to determine the effects of three factors (spectral composition, photoperiod, and light intensity) on the gonadal development of Atlantic salmon in RAS. We demonstrated that the photoperiod at the tested levels had a much greater effect on the gonadosomatic index and female Fulton condition factor than spectral composition and light intensity. The photoperiod had a significant effect on the secretion of sex steroids and melatonin ( P<0.05), and a short photoperiod delayed sex steroid and melatonin level increases. The three test factors had no significant effects on the survival rate, specific growth rate, relative weight gain, and male Fulton condition factor ( P>0.05). The optimum lighting levels in female and male Atlantic salmon were LD 8:16, 455 nm (or 625 nm), 8.60 W/m2; and LD 8:16, 8.60 W/m2, 455 nm respectively. These conditions not only delayed gonadal development, but also had no negative effects on Atlantic salmon growth in RAS. These results demonstrate that a combination of spectral composition, photoperiod and light intensity is effective at delaying the gonadal development of both male and female salmon in RAS.

Qiu, Denggao; Xu, Shihong; Song, Changbin; Chi, Liang; Li, Xian; Sun, Guoxiang; Liu, Baoliang; Liu, Ying

2015-01-01

241

Effects of spectral composition, photoperiod and light intensity on the gonadal development of Atlantic salmon Salmo salar in recirculating aquaculture systems (RAS)  

NASA Astrophysics Data System (ADS)

Artificial lighting regimes have been successfully used to inhibit sexual maturity of Atlantic salmon in confinement. However, when these operations are applied in commercial recirculating aquaculture systems (RAS) using standard lighting technology, sexual maturation is not suppressed. In this study, an L9 (33) orthogonal design was used to determine the effects of three factors (spectral composition, photoperiod, and light intensity) on the gonadal development of Atlantic salmon in RAS. We demonstrated that the photoperiod at the tested levels had a much greater effect on the gonadosomatic index and female Fulton condition factor than spectral composition and light intensity. The photoperiod had a significant effect on the secretion of sex steroids and melatonin (P<0.05), and a short photoperiod delayed sex steroid and melatonin level increases. The three test factors had no significant effects on the survival rate, specific growth rate, relative weight gain, and male Fulton condition factor (P>0.05). The optimum lighting levels in female and male Atlantic salmon were LD 8:16, 455 nm (or 625 nm), 8.60 W/m2; and LD 8:16, 8.60 W/m2, 455 nm respectively. These conditions not only delayed gonadal development, but also had no negative effects on Atlantic salmon growth in RAS. These results demonstrate that a combination of spectral composition, photoperiod and light intensity is effective at delaying the gonadal development of both male and female salmon in RAS.

Qiu, Denggao; Xu, Shihong; Song, Changbin; Chi, Liang; Li, Xian; Sun, Guoxiang; Liu, Baoliang; Liu, Ying

2014-10-01

242

Greenhouse Tomato Production with High Saline Nutrient Solution Simulating a Re-circulating Irrigation System without Environmental Discharge  

E-print Network

transpiration is a very important physiological process for plant growth. It serves as the driving force significantly increased % Brix, acidity, and firmness, while transpiration regime seems to have no effect organs and fruits, is dependent on the environmental conditions that govern plant water status, nutrient

Fay, Noah

243

Solar heating and hot water system installed at Arlington Raquetball Club, Arlington, Virginia  

NASA Technical Reports Server (NTRS)

A solar space and water heating system is described. The solar energy system consists of 2,520 sq. ft. of flat plate solar collectors and a 4,000 gallon solar storage tank. The transfer medium in the forced closed loop is a nontoxic antifreeze solution (50 percent water, 50 percent propylene glycol). The service hot water system consists of a preheat coil (60 ft. of 1 1/4 in copper tubing) located in the upper third of the solar storage tank and a recirculation loop between the preheat coil and the existing electric water heaters. The space heating system consists of two separate water to air heat exchangers located in the ducts of the existing space heating/cooling systems. The heating water is supplied from the solar storage tank. Extracts from site files, specification references for solar modifications to existing building heating and hot water systems, and installation, operation and maintenance instructions are included.

1981-01-01

244

Water Purification Systems  

NASA Technical Reports Server (NTRS)

Clearwater Pool Technologies employs NASA-developed silver/copper ionization to purify turtle and dolphin tanks, cooling towers, spas, water recycling systems, etc. The pool purifier consists of a microcomputer to monitor water conditions, a pair of metallic electrodes, and a rheostat controller. Ions are generated by passing a low voltage current through the electrodes; the silver ions kill the bacteria, and the copper ions kill algae. This technology has found broad application because it offers an alternative to chemical disinfectants. It was originally developed to purify water on Apollo spacecraft. Caribbean Clear has been using NASA's silver ionization technology for water purification for more than a decade. Two new products incorporate advancements of the basic technology. One is the AquaKing, a system designed for areas with no source of acceptable drinking water. Another is the Caribbean Clear Controller, designed for commercial pool and water park applications where sanitizing is combined with feedback control of pH and an oxidizer, chlorine or bromine. The technology was originally developed to purify water on Apollo spacecraft.

1994-01-01

245

Effect of Dietary Supplementation of Brewer's Yeast and GroBiotic®-A on Growth, Immune Responses, and Low-Salinity Tolerance of Pacific White Shrimp Litopenaeus vannamei Cultured in Recirculating Systems  

Microsoft Academic Search

Two separate trials were conducted in clean recirculating systems at salinities of 32.9 (optimal) and 2 ppt (low-salinity challenge) to evaluate brewer's yeast and GroBiotic®-A, a commercial prebiotic, as dietary supplements for growth and health management of Pacific white shrimp Litopenaeus vannamei. The growth-promoting influences of brewer's yeast or GroBiotic®-A previously observed with fish were not demonstrated in these trials

Peng Li; Xiaoxue Wang; Shivananda Murthy; Delbert M. Gatlin III; Frank L. Castille; Addison L. Lawrence

2009-01-01

246

Aeration recirculation in air and high purity oxygen systems for control of VOC emissions from wastewater aeration basins  

Microsoft Academic Search

A steady state circulating aeration system (CAS) model has been used to study the effects of volatility and degradability on the fate of VOCs in both air and high purity oxygen (HPO) systems. With an increase of the circulating ratio in an air CAS, air emissions by stripping can be significantly reduced for compounds of low degradability and high volatility.

H. Zhu; T. C. Keener; P. L. Bishop; T. L. Orton; M. Wang; K. F. Siddiqui

2009-01-01

247

Safety system consideration of a supercritical-water cooled fast reactor with simplified PSA  

Microsoft Academic Search

The probabilistic safety of the supercritical-water cooled fast reactor (SCFR) is evaluated with the simplified probabilistic safety assessment (PSA) methodology. SCFR has a once-through direct cycle where all feedwater flows through the core to the turbine at supercritical pressure. There are no recirculation loops in the once-through direct cycle system, which is the most important difference from the current light

J. H Lee; Y Oka; S Koshizuka

1999-01-01

248

Water system virus detection  

NASA Technical Reports Server (NTRS)

A monitoring system developed to test the capability of a water recovery system to reject the passage of viruses into the recovered water is described. A nonpathogenic marker virus, bacteriophage F2, is fed into the process stream before the recovery unit and the reclaimed water is assayed for its presence. Detection of the marker virus consists of two major components, concentration and isolation of the marker virus, and detection of the marker virus. The concentration system involves adsorption of virus to cellulose acetate filters in the presence of trivalent cations and low pH with subsequent desorption of the virus using volumes of high pH buffer. The detection of the virus is performed by a passive immune agglutination test utilizing specially prepared polystyrene particles. An engineering preliminary design was performed as a parallel effort to the laboratory development of the marker virus test system. Engineering schematics and drawings of a fully functional laboratory prototype capable of zero-G operation are presented. The instrument consists of reagent pump/metering system, reagent storage containers, a filter concentrator, an incubation/detector system, and an electronic readout and control system.

Fraser, A. S.; Wells, A. F.; Tenoso, H. J.

1975-01-01

249

Spacesuit Water Membrane Evaporator; An Enhanced Evaporative Cooling Systems for the Advanced Extravehicular Mobility Unit Portable Life Support System  

NASA Technical Reports Server (NTRS)

Spacesuit Water Membrane Evaporator - Baseline heat rejection technology for the Portable Life Support System of the Advanced EMU center dot Replaces sublimator in the current EMU center dot Contamination insensitive center dot Can work with Lithium Chloride Absorber Radiator in Spacesuit Evaporator Absorber Radiator (SEAR) to reject heat and reuse evaporated water The Spacesuit Water Membrane Evaporator (SWME) is being developed to replace the sublimator for future generation spacesuits. Water in LCVG absorbs body heat while circulating center dot Warm water pumped through SWME center dot SWME evaporates water vapor, while maintaining liquid water - Cools water center dot Cooled water is then recirculated through LCVG. center dot LCVG water lost due to evaporation (cooling) is replaced from feedwater The Independent TCV Manifold reduces design complexity and manufacturing difficulty of the SWME End Cap. center dot The offset motor for the new BPV reduces the volume profile of the SWME by laying the motor flat on the End Cap alongside the TCV.

Bue, Grant C.; Makinen, Janice V.; Miller, Sean.; Campbell, Colin; Lynch, Bill; Vogel, Matt; Craft, Jesse; Petty, Brian

2014-01-01

250

Automatic water heater systems  

Microsoft Academic Search

A heat trap is described which can be connected to the flue exhaust outlet of an automatic gas water heating system in which heat can be entrapped that would otherwise be lost via hot flue gases passing up through the flue exhaust and out of a chimney. The heat trap comprises a tank containing therein vertically extending serpentine heat tubes.

R. O. Jr

1987-01-01

251

Water-quality modeling of Klamath Straits Drain recirculation, a Klamath River wetland, and 2011 conditions for the Link River to Keno Dam reach of the Klamath River, Oregon  

USGS Publications Warehouse

The upper Klamath River and adjacent Lost River are interconnected basins in south-central Oregon and northern California. Both basins have impaired water quality with Total Maximum Daily Loads (TMDLs) in progress or approved. In cooperation with the Bureau of Reclamation, the U.S. Geological Survey (USGS) and Watercourse Engineering, Inc., have conducted modeling and research to inform management of these basins for multiple purposes, including agriculture, endangered species protection, wildlife refuges, and adjacent and downstream water users. A water-quality and hydrodynamic model (CE-QUAL-W2) of the Link River to Keno Dam reach of the Klamath River for 2006–09 is one of the tools used in this work. The model can simulate stage, flow, water velocity, ice cover, water temperature, specific conductance, suspended sediment, nutrients, organic matter in bed sediment and the water column, three algal groups, three macrophyte groups, dissolved oxygen, and pH. This report documents two model scenarios and a test of the existing model applied to year 2011, which had exceptional water quality. The first scenario examined the water-quality effects of recirculating Klamath Straits Drain flows into the Ady Canal, to conserve water and to decrease flows from the Klamath Straits Drain to the Klamath River. The second scenario explicitly incorporated a 2.73×106 m2 (675 acre) off-channel connected wetland into the CE-QUAL-W2 framework, with the wetland operating from May 1 through October 31. The wetland represented a managed treatment feature to decrease organic matter loads and process nutrients. Finally, the summer of 2011 showed substantially higher dissolved-oxygen concentrations in the Link-Keno reach than in other recent years, so the Link-Keno model (originally developed for 2006–09) was run with 2011 data as a test of model parameters and rates and to develop insights regarding the reasons for the improved water-quality conditions.

Sullivan, Annett B.; Sogutlugil, I. Ertugrul; Deas, Michael L.; Rounds, Stewart A.

2014-01-01

252

Growth performance, fillet quality, and reproductive maturity of rainbow trout (Oncorhynchus mykiss) cultured to 5 kilograms within freshwater recirculating systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

Rainbow trout are commonly cultured within aquaculture systems to one pound or less and marketed as pan-sized fillets. Production of larger rainbow trout provides a distinguishable product. Research that describes the growth performance and fillet quality of large rainbow trout is limited, particula...

253

Development of a Vertical Recirculation Well System for the A/M Area of the Savannah River Site  

SciTech Connect

The objective of this work is to examine and develop a remediation scenario to provide long term hydraulic control and remediation of the dissolved chlorinated solvent plume within the Western and Southern Sectors of the A/M Area. This scope includes the development and siting of a remediation system that will contain the 500 part per billion trichloroethylene isoconcentration contour within each sector.

Jackson, D.G. Jr. [Westinghouse Savannah River Company, AIKEN, SC (United States); Looney, B.B.

1996-09-13

254

Identification and origin of plant pathogenic microorganisms in recirculating nutrient solutions.  

PubMed

Avoidance of root-infecting microorganisms was originally considered one of the advantages of cultivation of crops in a soilless, recirculating nutrient solution. However, to date, four viral, three bacterial and 21 fungal pathogens have been identified as causal agents of root disease in hydroponically-grown crops. Root-infecting fungi, particularly those which produce a motile stage known as a zoospore, have been the primary pathogens associated with extensive crop losses. Documented sources of these root pathogens in hydroponic systems include peat, surface water such as rivers and streams, and insects. The severity of disease caused by these introduced root pathogens is primarily governed by the genetic susceptibility of each crop and the temperature of the recirculating nutrient solution. PMID:11540205

Stanghellini, M E; Rasmussen, S L

1994-11-01

255

Dietary supplementation of short-chain fructooligosaccharides influences gastrointestinal microbiota composition and immunity characteristics of Pacific white shrimp, Litopenaeus vannamei, cultured in a recirculating system.  

PubMed

Supplementation of prebiotic compounds, including short-chain fructooligosaccharides (scFOS) has been shown to confer benefits on nutrient utilization, growth, and disease resistance of various animal species through improved gastrointestinal (GI) microbiota. However, potential uses of prebiotics for shrimp have not been defined. A 6-wk feeding trial was conducted in a recirculating system to determine the effects of scFOS supplementation on growth performance, immune functions, and GI microbiota composition of Pacific white shrimp (Litopenaeus vannamei). scFOS was supplemented in a nutritionally complete diet (35% crude protein) at 0.025, 0.0500, 0.075, 0.100, 0.200, 0.400, and 0.800% by weight. After 6 wk of feeding, shrimp fed 0, 0.1, and 0.8% scFOS were sampled for assays of immune function and GI microbiota. Dietary supplementation of scFOS did not improve weight gain, feed conversion ratio, or survival of shrimp. Denaturing gradient gel electrophoresis analysis suggested the intestinal tract microbial community from shrimp fed the basal diet was different from that of shrimp fed the scFOS diets [similarity coefficient (SC) = 74.9%)], although the intestinal tract microbial community from shrimp fed the scFOS-supplemented diets was very similar (SC = 92.3%). All the bacterial species contributing to the GI microbial differences were identified, although most of them are uncultured species. Both total hemocyte count and hemocyte respiratory burst increased (P < 0.05) by incremental dietary supplementation of scFOS (0-0.8%). This study is the first to our knowledge to show that dietary scFOS can selectively support growth of certain bacterial species in the GI tract of shrimp and enhance immunity, which may facilitate development of alternative strategies, including novel probiotics and synbiotics, for shrimp growth and health management. PMID:18029496

Li, Peng; Burr, Gary S; Gatlin, Delbert M; Hume, Michael E; Patnaik, Susmita; Castille, Frank L; Lawrence, Addison L

2007-12-01

256

Chilled water system optimization  

SciTech Connect

There are several questions that the engineer responsible for efficiently operating or designing the controls for a large chilled water (CHW) system needs to answer: What is the optimum combination of chillers to operate Should he start the chiller that will operate more fully loaded or the nominally most efficient chiller What is the optimum condenser water temperature for the system at different loads and outdoor conditions Should he try to use the maximum surface area of his cooling towers Can he reduce the flow to a cell too much Should he increase condenser water pump power to achieve a decrease in chiller power What is the offsetting effect on cooling tower performance These and other questions were answered during the design of a CHW plant automation and optimization project at a major pharmaceutical company's North Carolina manufacturing facility. This article includes a description of the performance of individual pieces of equipment, an analysis of the integrated system, and the preferred sequences of operation. Although the analysis is specific for this application, the evaluation procedure can be adapted to any system.

Austin, S.B. (Burroughs Wellcome Co., Greenville, NC (United States). Engineering Facilities and Utilities Dept.)

1993-07-01

257

Smart Water: Energy-Water Optimization in Drinking Water Systems  

EPA Science Inventory

This project aims to develop and commercialize a Smart Water Platform ? Sensor-based Data-driven Energy-Water Optimization technology in drinking water systems. The key technological advances rely on cross-platform data acquisition and management system, model-based real-time sys...

258

THERMOSYPHON BATCH AND REGENERATIVE TURBINE RECIRCULATING 18 O(P,N) 18 F WATER TARGETS FOR OPERATION AT HIGH BEAM POWER  

Microsoft Academic Search

AIMS: Improved boiling water target designs and body materials for the production of ( 18 F)fluoride ion have evolved steadily over the last two decades (1), and reliable operation at beam power up to one kilowatt has been achieved. Our goal is to extend this beam power limit to two kW for boiling water targets through use of the thermosyphon

BW Wieland; BC Wright; GT Bida; CD Illan; JM Doster; JC Clark; RC Runkle

259

Recirculating immunomagnetic separation and optimal enrichment conditions for enhanced detection and recovery of low levels of Escherichia coli O157:H7 from fresh leafy produce and surface water.  

PubMed

The objective of this study was to develop a rapid, simple method for enhanced detection and isolation of low levels of Escherichia coli O157:H7 from leafy produce and surface water using recirculating immunomagnetic separation (RIMS) coupled with real-time PCR and a standard culture method. The optimal enrichment conditions for the method also were determined. Analysis of real-time PCR data (C(T) values) suggested that incubation of lettuce and spinach leaves rather than rinsates provides better enrichment of E. coli O157:H7. Enrichment of lettuce or spinach leaves at 42 degrees C for 5 h provided better detection than enrichment at 37 degrees C. Extended incubation of surface water for 20 h at 42 degrees C did not improve the detection. The optimized enrichment conditions were also employed with modified Moore swabs, which were used to sample flowing water sites. Positive isolation rates and real-time PCR results indicated an increased recovery of E. coli O157:H7 from all samples following the application of RIMS. Under these conditions, the method provided detection and/or isolation of E. coli O157:H7 at levels as low as 0.07 CFU/g of lettuce, 0.1 CFU/g of spinach, 6 CFU/100 ml of surface water, and 9 CFU per modified Moore swab. During a 6-month field study, modified Moore swabs yielded high isolation rates when deployed in natural watershed sites. The method used in this study was effective for monitoring E. coli O157:H7 in the farm environment, during postharvest processing, and in foodborne outbreak investigations. PMID:18095422

Himathongkham, Sunee; Dodd, Mary Lee; Yee, Jenny K; Lau, David K; Bryant, Raymond G; Badoiu, Alexandru S; Lau, Henry K; Guthertz, Linda S; Crawford-Miksza, Leta; Soliman, Mary A

2007-12-01

260

Integrated Planning for Water and Energy Systems  

E-print Network

of water in a specific location. #12;Water Extraction & Conveyance Water Treatment End-Use Agricultural Residential Commercial Industrial Water Distribution Wastewater Treatment Wastewater Collection Wastewater Discharge Recycled Water Treatment Recycled Water Distribution Source Source Energy Inputs to Water Systems

Keller, Arturo A.

261

Automated Water-Purification System  

NASA Technical Reports Server (NTRS)

Reverse-osmosis system operates and maintains itself with minimal human attention, using programmable controller. In purifier, membranes surround hollow cores through which clean product water flows out of reverse-osmosis unit. No chemical reactions or phase changes involved. Reject water, in which dissolved solids concentrated, emerges from outer membrane material on same side water entered. Flow controls maintain ratio of 50 percent product water and 50 percent reject water. Membranes expected to last from 3 to 15 years.

Ahlstrom, Harlow G.; Hames, Peter S.; Menninger, Fredrick J.

1988-01-01

262

Evaluation of three types of structured floating plastic media in moving bed biofilters for total ammonia nitrogen removal in a low salinity hatchery recirculating aquaculture system  

Technology Transfer Automated Retrieval System (TEKTRAN)

Three different commercially available structural plastic media were evaluated in triplicate in moving bed toriod filters under low salinity (11-12 ppt) warm water culture conditions and two different feed loading rates. The culture system consisted of nine separate modules that include a double dra...

263

Field evaluation of a horizontal well recirculation system for groundwater treatment: Field demonstration at X-701B Portsmouth Gaseous Diffusion Plant, Piketon, Ohio  

SciTech Connect

This report describes the field-scale demonstration performed as part of the project, In Situ Treatment of Mixed Contaminants in Groundwater. This project was a 3{1/2} year effort comprised of laboratory work performed at Oak Ridge National Laboratory and fieldwork performed at the US Department of Energy (DOE) Portsmouth Gaseous Diffusion Plant (PORTS). The overall goal of the project was to evaluate in situ treatment of groundwater using horizontal recirculation coupled with treatment modules. Specifically, horizontal recirculation was tested because of its application to thin, interbedded aquifer zones. Mixed contaminants were targeted because of their prominence at DOE sites and because they cannot be treated with conventional methods. The project involved several research elements, including treatment process evaluation, hydrodynamic flow and transport modeling, pilot testing at an uncontaminated site, and full-scale testing at a contaminated site. This report presents the results of the work at the contaminated site, X-701B at PORTS. Groundwater contamination at X-701B consists of trichloroethene (TCE) (concentrations up to 1800 mg/L) and technetium-998 (Tc{sup 99}) (activities up to 926 pCi/L).

Korte, N.; Muck, M.; Kearl, P.; Siegrist, R.; Schlosser, R.; Zutman, J. [Oak Ridge National Lab., TN (United States)] [Oak Ridge National Lab., TN (United States); Houk, T. [Lockheed Martin Energy Systems, Piketon, OH (United States). Portsmouth Gaseous Diffusion Plant] [Lockheed Martin Energy Systems, Piketon, OH (United States). Portsmouth Gaseous Diffusion Plant

1998-08-01

264

10 Commercially Feasible Urban Recirculating Aquaculture: Addressing the Marine Sector  

Microsoft Academic Search

With the global collapse of marine fisheries and the environmental issues associated with net-pen aquaculture practices, there is a pressing need to develop fully contained and environmentally sus- tainable approaches to producing seafood. Recirculating aquaculture systems (RAS), which provide this approach, have been widely used over the last two decades to farm freshwater species. However, the cost associated with the

Yonathan Zohar; Yossi Tal; Harold Schreier; Colin Steven; John Stubblefield

265

Recirculation in multiple wave conversions  

SciTech Connect

A one-dimensional multiple wave-conversion model is constructed that allows energy recirculation in ray phase space. Using a modular eikonal approach, the connection coefficients for this model are calculated by ray phase-space methods. Analytical results (confirmed numerically) show that all connection coefficients exhibit interference effects that depend on an interference phase, calculated from the coupling constants and the area enclosed by the intersecting rays. This conceptual model, which focuses on the topology of intersecting rays in phase space, is used to investigate how mode conversion between primary and secondary waves is modified by the presence of a tertiary wave.

Kaufman, A. N.; Brizard, A.J.; Kaufman, A.N.; Tracy, E.R.

2008-07-30

266

Recirculation in multiple wave conversions  

SciTech Connect

A one-dimensional multiple wave-conversion model is constructed that allows energy recirculation in ray phase space. Using a modular eikonal approach, the connection coefficients for this model are calculated by ray phase-space methods. Analytical results (confirmed numerically) show that all connection coefficients exhibit interference effects that depend on an interference phase, calculated from the coupling constants and the area enclosed by the intersecting rays. This conceptual model, which focuses on the topology of intersecting rays in phase space, is used to investigate how mode conversion between primary and secondary waves is modified by the presence of a tertiary wave.

Brizard, A. J. [Department of Chemistry and Physics, Saint Michael's College, Colchester, Vermont 05439 (United States); Kaufman, A. N. [Department of Physics and Lawrence Berkeley National Laboratory, University of California, Berkeley, California 94720 (United States); Tracy, E. R. [Department of Physics, College of William and Mary, Williamsburg, Virginia 23187-8795 (United States)

2008-08-15

267

In Situ Biotreatment of TBA with Recirculation/Oxygenation.  

PubMed

The potential for in situ biodegradation of tert-butyl alcohol (TBA) by creation of aerobic conditions in the subsurface with recirculating well pairs was investigated in two field studies conducted at Vandenberg Air Force Base (VAFB). In the first experiment, a single recirculating well pair with bromide tracer and oxygen amendment successfully delivered oxygen to the subsurface for 42 days. TBA concentrations were reduced from approximately 500 ?g/L to below the detection limit within the treatment zone and the treated water was detected in a monitoring transect several meters downgradient. In the second experiment, a site-calibrated model was used to design a double recirculating well pair with oxygen amendment, which successfully delivered oxygen to the subsurface for 291 days and also decreased TBA concentrations to below the detection limit. Methylibium petroleiphilum strain PM1, a known TBA-degrading bacterium, was detectable at the study site but addition of oxygen had little impact on the already low baseline population densities, suggesting that there was not enough carbon within the groundwater plume to support significant new growth in the PM1 population. Given favorable hydrogeologic and geochemical conditions, the use of recirculating well pairs to introduce dissolved oxygen into the subsurface is a viable method to stimulate in situ biodegradation of TBA or other aerobically-degradable aquifer contaminants. PMID:23358537

North, Katharine P; Mackay, Douglas M; Kayne, Julian S; Petersen, Daniel; Rasa, Ehsan; Rastegarzadeh, Laleh; Holland, Reef B; Scow, Kate M

2012-01-01

268

In Situ Biotreatment of TBA with Recirculation/Oxygenation  

PubMed Central

The potential for in situ biodegradation of tert-butyl alcohol (TBA) by creation of aerobic conditions in the subsurface with recirculating well pairs was investigated in two field studies conducted at Vandenberg Air Force Base (VAFB). In the first experiment, a single recirculating well pair with bromide tracer and oxygen amendment successfully delivered oxygen to the subsurface for 42 days. TBA concentrations were reduced from approximately 500 ?g/L to below the detection limit within the treatment zone and the treated water was detected in a monitoring transect several meters downgradient. In the second experiment, a site-calibrated model was used to design a double recirculating well pair with oxygen amendment, which successfully delivered oxygen to the subsurface for 291 days and also decreased TBA concentrations to below the detection limit. Methylibium petroleiphilum strain PM1, a known TBA-degrading bacterium, was detectable at the study site but addition of oxygen had little impact on the already low baseline population densities, suggesting that there was not enough carbon within the groundwater plume to support significant new growth in the PM1 population. Given favorable hydrogeologic and geochemical conditions, the use of recirculating well pairs to introduce dissolved oxygen into the subsurface is a viable method to stimulate in situ biodegradation of TBA or other aerobically-degradable aquifer contaminants. PMID:23358537

North, Katharine P.; Mackay, Douglas M.; Kayne, Julian S.; Petersen, Daniel; Rasa, Ehsan; Rastegarzadeh, Laleh; Holland, Reef B.; Scow, Kate M.

2012-01-01

269

Compromise between ventilation, filtration strategies and recirculation rates for the design and operation of air-conditioned facilities in the tropics  

Microsoft Academic Search

This study examines the impact of filtration, ventilation and recirculation rate on concentration of condensed-phase, ozone (of outdoor origin)-derived oxidation products (secondary organic aerosols (SOA)) in a model room with a ventilation system that recirculates a large percentage (90%) of its supply air. Additionally, it critically evaluates the potential approach for filtering recirculated air and also avoiding the negative consequence

Moshood Olawale Fadeyi

2012-01-01

270

Gas recirculator for acyclic machines  

NASA Astrophysics Data System (ADS)

The present invention relates to acyclic machines of the type using liquid metal collectors, and more particularly to an improvement for retaining the liquid metal in such machines. Radial type acyclic motors and generators generally include a metallic disk rotor rotating on a shaft between electromagnetic stator poles excited by field coils wound concentric with the shaft. Instead of solid brush, current collectors at the rotor periphery, liquid metal collectors are sometimes used to close the electrical current loop between the shaft and the rotor, and an inert pressurized cover gas fills the gaps between the rotating components and the stationary housing. A cover has recirculator in an acyclic generator having liquid metal collectors for reducing entrainment of the liquid metal in the gas. Radial passages in the stator housing provide natural recirculating paths for the cover gas to flow radially outward along the sides of the rotor and return inwardly through the passages. Scoops or lips located inward of the liquid metal collector divert the outward gas flow into the passages to minimize contact of the gas with the liquid metal.

Balsa, T. F.

1985-05-01

271

Evaluation of three types of structured floating plastic media in moving bed biofilters for total ammonia nitrogen removal in a low salinity hatchery recirculating aquaculture system  

Microsoft Academic Search

Three different commercially available structural plastic media were evaluated in triplicate in moving bed biofilters under low salinity (11–12 ppt) warm water culture conditions and two different feed loading rates. The culture system consisted of nine separate modules that include a double drain fish culture tank paired to a moving bed biofilter. The biofilters were filled with 0.11m3 of one

Timothy J. Pfeiffer; Paul S. Wills

2011-01-01

272

COMMUNITY WATER SYSTEM SURVEY (CWSS)  

EPA Science Inventory

Resource Purpose: The CWSS is a national random sample of approximately 2,000 community water systems. The primary purpose of the CWSS is to provide OGWDW with data on the financial and operating characteristics of water systems. This information is used to support the o...

273

Water Treatment Technology - Distribution Systems.  

ERIC Educational Resources Information Center

One of twelve water treatment technology units, this student manual on distribution systems provides instructional materials for six competencies. (The twelve units are designed for a continuing education training course for public water supply operators.) The competencies focus on the following areas: types of pipe for distribution systems, types…

Ross-Harrington, Melinda; Kincaid, G. David

274

Industrial Energy Conservation, Forced Internal Recirculation Burner  

SciTech Connect

The overall objective of this research project is to develop and evaluate an industrial low NOx burner for existing and new gas-fired combustion systems for intermediate temperature (1400 degree to 2000 degree F) industrial heating devices such as watertube boilers and process fluid heaters. A multi-phase effort is being pursued with decision points to determine advisability of continuance. The current contract over Phases II and III of this work. The objectives of each phase are as follows. Phase II - to design, fabricate, and evaluate prototype burners based on the Forced Internal Recirculation (FIR) concept. Phase III - to evaluate the performance of an FIR burner under actual operating conditions in a full-scale field test and establish the performance necessary for subsequent commercialization

Joseph Rabovitser

2003-06-19

275

Dynamic simulation of large boilers with natural recirculation  

Microsoft Academic Search

This paper presents a dynamic simulator of water-in-tube boilers with natural recirculation, the kind of equipment widely used in industries for steam generation either as a source of power or for providing heating capabilities in process plants. The development is based on a combination of two non-linear models, one for the evaporation in the vertical tubes and the other for

E. J. Adam; J. L. Marchetti

1999-01-01

276

Water-based intumescent paint  

NASA Technical Reports Server (NTRS)

Article discusses fire-resistant water-based paints made by adding intumescing agents to fluorocarbon coatings. Since these paints are water-based, they do not pollute atmosphere as they dry and can be used in closed-loop air-recirculation system in spacecraft and submarines.

Sauers, D. G.; Nannelli, P.

1979-01-01

277

Semi-continuous anaerobic co-digestion of cow manure and steam-exploded Salix with recirculation of liquid digestate.  

PubMed

The effects of recirculating the liquid fraction of the digestate during mesophilic anaerobic co-digestion of steam-exploded Salix and cow manure were investigated in laboratory-scale continuously stirred tank reactors. An average organic loading rate of 2.6 g VS L(-1) d(-1) and a hydraulic retention time (HRT) of 30 days were employed. Co-digestion of Salix and manure gave better methane yields than digestion of manure alone. Also, a 16% increase in the methane yield was achieved when digestate was recirculated and used instead of water to dilute the feedstock (1:1 dilution ratio). The reactor in which the larger fraction of digestate was recirculated (1:3 dilution ratio) gave the highest methane yields. Ammonia and volatile fatty acids did not reach inhibitory levels, and some potentially inhibitory compounds released during steam explosion (i.e., furfural and 5-hydroxy methyl furfural) were only detected at trace levels throughout the entire study period. However, accumulation of solids, which was more pronounced in the recycling reactors, led to decreased methane yields in those systems after three HRTs. Refraining from the use of fresh water to dilute biomass with a high-solids content and obtaining a final digestate with increased dry matter content might offer important economic benefits in full-scale processes. To ensure long-term stability in such an approach, it would be necessary to optimize separation of the fraction of digestate to be recirculated and also perform proper monitoring to avoid accumulation of solids. PMID:24534902

Estevez, Maria M; Sapci, Zehra; Linjordet, Roar; Schnürer, Anna; Morken, John

2014-04-01

278

The Exploration Water Recovery System  

NASA Technical Reports Server (NTRS)

The Exploration Water Recovery System is designed towards fulfillment of NASA s Vision for Space Exploration, which will require elevation of existing technologies to higher levels of optimization. This new system, designed for application to the Exploration infrastructure, presents a novel combination of proven air and water purification technologies. The integration of unit operations is modified from that of the current state-of-the-art water recovery system so as to optimize treatment of the various waste water streams, contaminant loads, and flow rates. Optimization is achieved primarily through the removal of volatile organic contaminants from the vapor phase prior to their absorption into the liquid phase. In the current state-of-the-art system, the water vapor in the cabin atmosphere is condensed, and the volatile organic contaminants present in that atmosphere are absorbed into the aqueous phase. Removal of contaminants the5 occurs via catalytic oxidation in the liquid phase. Oxidation kinetics, however, dictate that removal of volatile organic contaminants from the vapor phase can inherently be more efficient than their removal from the aqueous phase. Taking advantage of this efficiency reduces the complexity of the water recovery system. This reduction in system complexity is accompanied by reductions in the weight, volume, power, and resupply requirements of the system. Vapor compression distillation technology is used to treat the urine, condensate, and hygiene waste streams. This contributes to the reduction in resupply, as incorporation of vapor compression distillation technology at this point in the process reduces reliance on the expendable ion exchange and adsorption media used in the current state-of-the-art water recovery system. Other proven technologies that are incorporated into the Exploration Water Recovery System include the Trace Contaminant Control System and the Volatile Removal Assembly.

ORourke, Mary Jane E.; Carter, Layne; Holder, Donald W.; Tomes, Kristin M.

2006-01-01

279

CASE FOR DRINKING WATER SYSTEMS  

EPA Science Inventory

The purpose of the study was to present a tool useful to water utilities that not only could analyze historical distribution system reliability data, but also provide a flexible and expandable mechanism for record-keeping enabling overall management of water work's facilities and...

280

SMALL DRINKING WATER SYSTEMS RESEARCH  

EPA Science Inventory

There are 159,796 Community Water Systems (CWSs) in the United States. Ninety-three percent of CWSs are considered very small to medium-sized systems that serve roughly 19% of the CWS population. In contrast, large to very large systems comprise just 7% of CWSs, but serve 81% of ...

281

Cyclone reactor with internal separation and axial recirculation  

DOEpatents

A cyclone combustor apparatus contains a circular partition plate containing a central circular aperture is described. The partition plate divides the apparatus into a cylindrical precombustor chamber and a combustor chamber. A coal-water slurry is passed axially into the inlet end of the precombustor chamber, and primary air is passed tangentially into said chamber to establish a cyclonic air flow. Combustion products pass through the partition plate aperture and into the combustor chamber. Secondary air may also be passed tangentially into the combustor chamber adjacent the partition plate to maintain the cyclonic flow. Flue gas is passed axially out of the combustor chamber at the outlet end and ash is withdrawn tangentially from the combustor chamber at the outlet end. A first mixture of flue gas and ash may be tangentially withdrawn from the combustor chamber at the outlet end and recirculated to the axial inlet of the precombustor chamber with the coal-water slurry. A second mixture may be tangentially withdrawn from the outlet end and passed to a heat exchanger for cooling. Cooled second mixture is then recirculated to the axial inlet of the precombustor chamber. In another embodiment a single cyclone combustor chamber is provided with both the recirculation streams of the first mixture and the second mixture. 10 figs.

Becker, F.E.; Smolensky, L.A.

1988-07-19

282

Cyclone reactor with internal separation and axial recirculation  

DOEpatents

A cyclone combustor apparatus contains a circular partition plate containing a central circular aperture. The partition plate divides the apparatus into a cylindrical precombustor chamber and a combustor chamber. A coal-water slurry is passed axially into the inlet end of the precombustor chamber, and primary air is passed tangentially into said chamber to establish a cyclonic air flow. Combustion products pass through the partition plate aperture and into the combustor chamber. Secondary air may also be passed tangentially into the combustor chamber adjacent the partition plate to maintain the cyclonic flow. Flue gas is passed axially out of the combustor chamber at the outlet end and ash is withdrawn tangentially from the combuston chamber at the outlet end. A first mixture of flue gas and ash may be tangentially withdrawn from the combustor chamber at the outlet end and recirculated to the axial inlet of the precombustor chamber with the coal-water slurry. A second mixture of flue gas and ash may be tangentially withdrawn from the outlet end of the combustor chamber and passed to a heat exchanger for cooling. Cooled second mixture is then recirculated to the axial inlet of the precombustor chamber. In another embodiment a single cyclone combustor chamber is provided with both the recirculation streams of the first mixture and the second mixture.

Becker, Frederick E. (Reading, MA); Smolensky, Leo A. (Concord, MA)

1989-01-01

283

Research on leachate recirculation from different types of landfills  

SciTech Connect

Landfills can produce a great amount of leachate containing highly concentrated organic matter. This is especially true for the initial leachate from landfilled municipal solid wastes (MSW) that generally has concentrations of COD{sub Cr} and BOD{sub 5} up to 80,000 and 50,000 mg/L, respectively. The leachate could be disposed by means of recirculating technique, which decomposes the organics through the action of proliferating microorganisms and thereby purifies the leachate, and simultaneously accelerates organic decomposition through water saturation control. Data from experimental results indicated that leachate recirculating could reduce the organic concentration considerably, with a maximum reduction rate of COD{sub Cr} over 95%; and, using a semi-aerobic process, NH{sub 3}-N concentration of treated leachate could be under 10 mg/L. In addition, the organic concentration in MSW decreased greatly.

Wang Qi [Research Institute of Solid Waste Management, Chinese Research Academy of Environmental Sciences, No. 8 of Dayangfang, Chaoyang District, Beijing 100012 (China) and Faculty of Engineering, Fukuoka University, 8-19-1 Nanakuma, Johnan-ku, Fukuoka 814-0180 (Japan)]. E-mail: wangqi@craes.org.cn; Matsufuji, Yasushi [Faculty of Engineering, Fukuoka University, 8-19-1 Nanakuma, Johnan-ku, Fukuoka 814-0180 (Japan); Dong Lu [Research Institute of Solid Waste Management, Chinese Research Academy of Environmental Sciences, No. 8 of Dayangfang, Chaoyang District, Beijing 100012 (China); Huang Qifei [Research Institute of Solid Waste Management, Chinese Research Academy of Environmental Sciences, No. 8 of Dayangfang, Chaoyang District, Beijing 100012 (China); Hirano, Fumiaki [Faculty of Engineering, Fukuoka University, 8-19-1 Nanakuma, Johnan-ku, Fukuoka 814-0180 (Japan); Tanaka, Ayako [Faculty of Engineering, Fukuoka University, 8-19-1 Nanakuma, Johnan-ku, Fukuoka 814-0180 (Japan)

2006-07-01

284

Systems and Components Fuel Delivery System, Water Delivery System, ...  

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

Systems and Components - Fuel Delivery System, Water Delivery System, Derrick Crane System, and Crane System Details - Marshall Space Flight Center, F-1 Engine Static Test Stand, On Route 565 between Huntsville and Decatur, Huntsville, Madison County, AL

285

TANK MIXING STUDY WITH FLOW RECIRCULATION  

SciTech Connect

The primary objective of this work is to quantify the mixing time when two miscible fluids are mixed by one recirculation pump and to evaluate adequacy of 2.5 hours of pump recirculation to be considered well mixed in SRS tanks, JT-71/72. The work scope described here consists of two modeling analyses. They are the steady state flow pattern analysis during pump recirculation operation of the tank liquid and transient species transport calculations based on the initial steady state flow patterns. The modeling calculations for the mixing time are performed by using the 99% homogeneity criterion for the entire domain of the tank contents.

Lee, S.

2014-06-25

286

Picosecond Pulse Recirculation for High Average Brightness Thomson Scattering-based Gamma-ray Sources  

SciTech Connect

Pulse recirculation has been successfully demonstrated with the interaction laser system of LLNL's Thomson-Radiated Extreme X-ray (T-REX) source. The recirculation increased twenty-eight times the intensity of the light coming out of the laser system, demonstrating the capability of increasing the gamma-ray flux emitted by T-REX. The technical approach demonstrated could conceivably increase the average gamma-ray flux output by up to a hundred times.

Semenov, V

2009-05-28

287

Clean Water Systems in Mexico  

NSDL National Science Digital Library

In this video segment adapted from Rx for Survival, learn about the importance of clean water and sanitation systems. Hear the story of how, in the early 1990s, Mexico's entry into a North American trade agreement was threatened by a cholera epidemic. Find out how the Mexican government rebuilt the water and sanitation system to stop the spread of the disease and how the investment in clean water helped the country win the trade agreement. A background essay, discussion questions, and standards correlations are also provided.

2010-08-31

288

Ephesus Municipal Water System Analysis  

NSDL National Science Digital Library

This project examines the entire water system of an ancient city, including supply, distribution, use, and drainage. Until now, individual water system elements have been studied as archaeological objects, but infrequently subjected to analysis by such disciplines as fluids engineering and urban history. This work is part of two larger long-term studies, the first concerning the relationship between physical setting and urban growth in the Greco-Roman world, and the second a comparative study of Old and New World water management techniques in the pre-modern period.

Crouch, Dora P.; Ortloff, Charles

1997-12-05

289

Recirculation, urea disequilibrium, and dialysis efficiency: peripheral arteriovenous versus central venovenous vascular access.  

PubMed

When accurate, non-urea-based methods of measuring recirculation are used, recirculation is usually absent in arteriovenous (AV) accesses. When urea-based methods are used to measure recirculation in AV accesses, falsely elevated recirculation rates are common. These errors are due to AV and venovenous disequilibrium (peripheral vein method), delayed systemic sampling (two-needle methods), and errors in urea measurement (all methods). The literature suggests that recirculation in central venovenous (CV) catheters is approximately 5%. The methods used for these determinations have all been urea based. However, there are few theoretical problems in using urea-based measurements for measuring recirculation in this setting, making it more likely that these values are accurate. When hemodialysis via CV and AV accesses are compared, equilibrated Kt/V values differ significantly for the same single-pool Kt/V when 15-second postdialysis blood urea nitrogen values are used for modeling, but differ minimally when 2-minute postdialysis samples are used. The impact of transient retrograde blood flow in the superior vena cava on recirculation and whether dialysis efficiency is influenced by the exact site of CV catheter placement (superior vena cava v right atrium) is uncertain. PMID:9100035

Sherman, R A; Kapoian, T

1997-04-01

290

Ultrapure Water System for Hemodialysis Therapy  

ClinicalTrials.gov

The Change of Biomarkers CRP, CBC With the Use of Ultra Pure Water System for; Hemodialysis.; The Rate of Adverse Events Such as Hypotension During Hemodialysis Therapy With Ultra Pure Water; System as Compared to Conventional Water System.

2011-07-21

291

Water in clay-water systems (1) Philip F. LOW  

E-print Network

Water in clay-water systems (1) Philip F. LOW Department of Agronomy, Purdue University. Agric. Exp. Stn., West Lafayette, IN 47907, U.S.A. SUMMARY The swelling of clay-water systems and the thermodynamic, hydrodynamic and spectroscopic properties of water in these systems are discussed. The swelling

Paris-Sud XI, Université de

292

Thermoelectric power systems and the energy-water nexus  

NASA Astrophysics Data System (ADS)

The goal of this Thesis is the development of a comprehensive methodology to evaluate the total cost of water use in the recirculating cooling loops of thermoelectric power plants. This methodology expands upon the work presented in the literature to improve estimations of the economic impact of condenser fouling. The methods developed in this Thesis are incorporated into a user friendly Combined Cost Model (CCM) interface that will allow future researchers, students and plant personnel to perform the same comparative analyses presented herein. The objective of this Thesis is the application of the CCM to determine the economic viability of treated municipal wastewater (MWW) use to replace freshwater for cooling in power plants with recirculating cooling systems. To accomplish this objective, a set of case study evaluations are included to (1) evaluate the sensitivity of the economic impact of fouling to condenser design and operation, (2) determine the cost of treated MWW use in pulverized coal power plants, and (3) compare the relative cost of degraded water use in advanced power systems such as IGCC and oxy-combustion. The results of these evaluations show that current freshwater prices do not provide an economic incentive to switch to the use of treated MWW water. However, results indicate that the breakeven differential price of freshwater, at which the total costs of using freshwater and treated MWW are equal, is only 0.52 /1000Gal. (USD 2009). In addition, the use of treated MWW for cooling is shown to be a better economic alternative to dry air cooling technology (DACT) for the conservation of freshwater resources. Cost-to-conservation estimates of treated MWW use are 1.1 /1000 Gal., in contrast to 5.6 $/1000 Gal. for DACT. This Thesis also presents a novel, hybrid coal conversion concept, the dry gasification oxy-combustion (DGOC) power cycle. This process is similar to oxy-combustion, in that it maintains a concentrated CO2 flue stream and does not utilize a complex separation step. However, coal conversion and sulfur removal are performed within a gasification unit. It is estimated to achieve CCS goals with a higher efficiency than the leading alternative strategies.

Walker, Michael Edward

293

Recirculating cross-correlation detector  

DOEpatents

A digital cross-correlation detector is provided in which two time-varying signals are correlated by repetitively comparing data samples stored in digital form to detect correlation between the two signals. The signals are sampled at a selected rate converted to digital form, and stored in separate locations in separate memories. When the memories are filled, the data samples from each memory are first fed word-by-word through a multiplier and summing circuit and each result is compared to the last in a peak memory circuit and if larger than the last is retained in the peak memory. Then the address line to leading signal memory is offset by one byte to affect one sample period delay of a known amount in that memory and the data in the two memories are then multiplied word-by-word once again and summed. If a new result is larger than a former sum, it is saved in the peak memory together with the time delay. The recirculating process continues with the address of the one memory being offset one additional byte each cycle until the address is shifted through the length of the memory. The correlation between the two signals is indicated by the peak signal stored in the peak memory together with the delay time at which the peak occurred. The circuit is faster and considerably less expensive than comparable accuracy correlation detectors.

Andrews, W.H. Jr.; Roberts, M.J.

1985-01-18

294

The global water systems project  

NASA Astrophysics Data System (ADS)

The Global Water System (GWS) plays a central and integrative role in the dynamics of the Earth system. It is a regulator of biogeophysical and biogeochemical processes, and it is also is essential for sustenance of human societies. The GWS is increasingly modified by humans and through climate effects (facets of it have moved well outside the range of natural variability), without adequate understanding of how the system works. For understanding the changes, feedbacks and potentially critical thresholds within the Earth system, and eventually for better managing the GWS, new synthetic knowledge is required. The Global Water System Project (GWSP) is a new activity being undertaken jointly by the World Climate Research Programme (WCRP), International Geophshere-Biosphere Program (IGBP), International Human Dimensions Program (IHP), and Diversitas. It will address the GWS in a comprehensive fashion at the global scale, building upon the emerging new consolidated Earth systems data sets, global monitoring tools, and predictive and coupled modeling capabilities. The central scientific question that motivates the GWSP is: "How are humans changing the global water cycle, the associated biogeochemical cycles, and the biological components of the GWS, and what are the social feedbacks arising from these changes?" GWSP will be structured around three "framing questions": a) What are the relative magnitudes of global-scale changes in the global water system that are attributable to changing human activities, and to environmental factors such as climate variability and change?; b) What are the main mechanisms by which human activities are affecting the global water system; and c) To what extent is the global water system resilient to global change? Examples of issues that might be addressed under each of these questions are provided.

Hoff, H.; Jaeger, C.; Leveque, C.; Lettenmaier, D.; Lins, H.; Meybeck, M.; Niasse, M.; Vorosmarty, C.

2003-04-01

295

Gilthead seabream (Sparus aurata) response to three music stimuli (Mozart-"Eine Kleine Nachtmusik," Anonymous-"Romanza," Bach-"Violin Concerto No. 1") and white noise under recirculating water conditions.  

PubMed

This study presents the results of the response of Sparus aurata to three different musical stimuli, derived from the transmission (4 h per day, 5 days per week) of particular music pieces by Mozart, Romanza and Bach (140 dBrms re 1 ?Pa), compared to the same transmission level of white noise, while the underwater ambient noise in all the experimental tanks was 121 dBrms re 1 ?Pa. Using recirculating sea water facilities, 10 groups, 2 for each treatment, of 20 specimens of 11.2 ± 0.02 g (S.E.), were reared for 94 days, under 150 ± 10 l× 12L-12D, and were fed an artificial diet three times per day. Fish body weight showed significant differences after 55 days, while its maximum level was observed after the 69th day until the end of the experiment, the highest value demonstrated in Mozart (M) groups, followed by those of Romanza (R), Bach (B), control (C) and white noise (WN). SGR (M = B), %WG (M = B) and FCR (all groups fed same % b.w.) were also improved for M group. Brain neurotransmitters results exhibited significant differences in DA-dopamine, (M > B), 5HIAA (C > B), 5HIAA:5HT (WN > R), DOPAC (M > B), DOPAC:DA and (DOPAC + HVA):DA, (C > M), while no significant differences were observed in 5HT, NA, HVA and HVA:DA. No differences were observed in biometric measurements, protease activity, % fatty acids of fillet, visceral fat and liver, while differences were observed regarding carbohydrase activity and the amount (mg/g w.w.) of some fatty acids in liver, fillet and visceral fat. In conclusion, present results confirm those reported for S. aurata, concerning the observed relaxing influence-due to its brain neurotransmitters action-of the transmission of Mozart music (compared to R and B), which resulted in the achievement of maximum growth rate, body weight and improved FCR. This conclusion definitely supports the musical "understanding" and sensitivity of S. aurata to music stimuli as well as suggesting a specific effect of white noise. PMID:25487611

Papoutsoglou, Sofronios E; Karakatsouli, Nafsika; Psarrou, Anna; Apostolidou, Sofia; Papoutsoglou, Eustratios S; Batzina, Alkisti; Leondaritis, Georgios; Sakellaridis, N

2014-12-01

296

Clemson University Water System Clemson, SC  

E-print Network

1 Clemson University Water System Clemson, SC 2000 Annual Water-Quality Report Clemson University water. We test our water using sophisticated equipment and advanced procedures. The water supplied by Clemson University Water System meets state and federal standards for both appearance and safety

Duchowski, Andrew T.

297

Clemson University Water System Clemson, SC  

E-print Network

1 Clemson University Water System Clemson, SC 2001 Annual Water-Quality Report Clemson University water. We test our water using sophisticated equipment and advanced procedures. The water supplied by Clemson University Water System meets state and federal standards for both appearance and safety

Duchowski, Andrew T.

298

Clemson University Water System Clemson, SC  

E-print Network

1 Clemson University Water System Clemson, SC 1999 Annual Water-Quality Report Clemson University water. We test our water using sophisticated equipment and advanced procedures. The water supplied by Clemson University Water System meets state and federal standards for both appearance and safety

Duchowski, Andrew T.

299

Fant's Grove Water System Clemson, SC  

E-print Network

1 Fant's Grove Water System Clemson, SC 2001 Annual Water-Quality Report Clemson University water. We test our water using sophisticated equipment and advanced procedures. The water supplied by Fant's Grove Water System meets state and federal standards for both appearance and safety. This annual

Duchowski, Andrew T.

300

Outdoor Laboratory Water System Clemson, SC  

E-print Network

1 Outdoor Laboratory Water System Clemson, SC 1999 Annual Water-Quality Report Clemson University water. We test our water using sophisticated equipment and advanced procedures. The water supplied by Outdoor Laboratory Water System meets state and federal standards for both appearance and safety

Duchowski, Andrew T.

301

Outdoor Laboratory Water System Clemson, SC  

E-print Network

1 Outdoor Laboratory Water System Clemson, SC 2000 Annual Water-Quality Report Clemson University water. We test our water using sophisticated equipment and advanced procedures. The water supplied by the Outdoor Laboratory Water System meets state and federal standards for both appearance and safety

Duchowski, Andrew T.

302

Drinking Water Distribution Systems Hydraulics, Leakage, and Water Quality Issues  

E-print Network

in California Water-Climate- Society Research #12;Contamination from the ground can intrude into our drinking#12; Drinking Water Distribution Systems Hydraulics, Leakage, and Water Quality Issues Life Cycle Assessment for Different Piping Materials Water Demand Analysis due to Water Meter Installation

Su, Xiao

303

Screening reactor steam\\/water piping systems for water hammer  

Microsoft Academic Search

A steam\\/water system possessing a certain combination of thermal, hydraulic and operational states, can, in certain geometries, lead to a steam bubble collapse induced water hammer. These states, operations, and geometries are identified. A procedure that can be used for identifying whether an unbuilt reactor system is prone to water hammer is proposed. For the most common water hammer, steam

1997-01-01

304

Recirculating vertical flow constructed wetland: green alternative to treating both human and animal sewage.  

PubMed

Subsurface constructed wetlands using a recirculating vertical flow are a viable alternative technology to pretreating conventional residential septic systems effluents before underground discharge. The authors examined performance of a recirculating vertical flow constructed wetland (RVFCW) to treat both human and domestic animal sewage from the LaGrange County (Indiana) Animal Shelter. Effluent water samples were analyzed for the five-day biochemical oxygen demand (BOD5), total suspended solids (TSS), ammonia-nitrogen (AN), total Kjeldhal nitrogen (TKN), total nitrogen (TN), nitrate-nitrogen, total phosphorus (TP) and fecal coliform bacteria (FC). Treatment efficiencies (percentage removal) after a two-year operation were high for BOD5 (99%), TSS (98%), AN (96%), TKN (94%), TN (83%), and FC (99%). Nitrate-nitrogen final mean value was 6.8 mg/L, dissolved oxygen concentration increased from 1.8 to 4.3 mg/L, and removal efficiency for total phosphorus was low (33%). These results show that vertical flow constructed wetlands are a green alternative to remove pollutants generated for both human and domestic animals. PMID:19908434

García-Pérez, Alfredo; Harrison, Mark; Grant, Bill

2009-11-01

305

Clemson University Water System System No, SC3910006  

E-print Network

1 Clemson University Water System System No, SC3910006 Clemson, SC 2003 Annual Water-Quality Report with a safe and reliable supply of high-quality drinking water. We test our water using sophisticated equipment and advanced procedures. The water supplied by Clemson University Water System meets state

Duchowski, Andrew T.

306

Clemson University Water System System No, SC3910006  

E-print Network

1 Clemson University Water System System No, SC3910006 Clemson, SC 2008 Annual Water-Quality Report and reliable supply of high-quality drinking water. We test our water using sophisticated equipment and advanced procedures. The water supplied by Clemson University Water System meets state and federal

Duchowski, Andrew T.

307

Fant's Grove Water System System No, SC390112  

E-print Network

1 Fant's Grove Water System System No, SC390112 Clemson, SC 2003 Annual Water-Quality Report with a safe and reliable supply of high-quality drinking water. We test our water using sophisticated equipment and advanced procedures. The water supplied by Clemson University Water System meets state

Duchowski, Andrew T.

308

Clemson University Water System System No, SC3910006  

E-print Network

1 Clemson University Water System System No, SC3910006 Clemson, SC 2005 Annual Water-Quality Report with a safe and reliable supply of high-quality drinking water. We test our water using sophisticated equipment and advanced procedures. The water supplied by Clemson University Water System meets state

Duchowski, Andrew T.

309

Clemson University Water System System No, SC3910006  

E-print Network

1 Clemson University Water System System No, SC3910006 Clemson, SC 2004 Annual Water-Quality Report with a safe and reliable supply of high-quality drinking water. We test our water using sophisticated equipment and advanced procedures. The water supplied by Clemson University Water System meets state

Duchowski, Andrew T.

310

Fant's Grove Water System System No, SC390112  

E-print Network

1 Fant's Grove Water System System No, SC390112 Clemson, SC 2004 Annual Water-Quality Report with a safe and reliable supply of high-quality drinking water. We test our water using sophisticated equipment and advanced procedures. The water supplied by the Fant's Grove Water System meets state

Duchowski, Andrew T.

311

An integrated closed system for fish-plankton aquaculture in Amazonian fresh water.  

PubMed

A prototype of an integrated closed system for fish-plankton aquaculture was developed in Iquitos (Peruvian Amazonia) in order to cultivate the Tiger Catfish, Pseudoplatystoma punctifer (Castelnau, 1855). This freshwater recirculating system consisted of two linked sewage tanks with an intensive rearing unit (a cage) for P. punctifer placed in the first, and with a fish-plankton trophic chain replacing the filters commonly used in clear water closed systems. Detritivorous and zooplanktivorous fishes (Loricariidae and Cichlidae), maintained without external feeding in the sewage volume, mineralized organic matter and permitted the stabilization of the phytoplankton biomass. Water exchange and organic waste discharge were not necessary. In this paper we describe the processes undertaken to equilibrate this ecosystem: first the elimination of an un-adapted spiny alga, Golenkinia sp., whose proliferation was favored by the presence of a small rotifer, Trichocerca sp., and second the control of this rotifer proliferation via the introduction of two cichlid species, Acaronia nassa Heckel, 1840 and Satanoperca jurupari Heckel, 1840, in the sewage part. This favored some development of the green algae Nannochloris sp. and Chlorella sp. At that time we took the opportunity to begin a 3-month rearing test of P. punctifer. The mean specific growth rate and feed conversion ratio (FCR) of P. punctifer were 1.43 and 1.27, respectively, and the global FCR, including fish in the sewage part, was 1.08. This system has proven to be suitable for growing P. punctifer juveniles out to adult, and provides several practical advantages compared with traditional recirculating clear water systems, which use a combination of mechanical and biological filters and require periodic waste removal, leading to water and organic matter losses. PMID:24849417

Gilles, S; Ismiño, R; Sánchez, H; David, F; Núñez, J; Dugué, R; Darias, M J; Römer, U

2014-05-22

312

Recirculation of Laser Power in an Atomic Fountain  

NASA Technical Reports Server (NTRS)

A new technique for laser-cooling atoms in a cesium atomic fountain frequency standard relies on recirculation of laser light through the atom-collection region of the fountain. The recirculation, accomplished by means of reflections from multiple fixed beam-splitter cubes, is such that each of two laser beams makes three passes. As described below, this recirculation scheme offers several advantages over prior designs, including simplification of the laser system, greater optical power throughput, fewer optical and electrical connections, and simplification of beam power balancing. A typical laser-cooled cesium fountain requires the use of six laser beams arranged as three orthogonal pairs of counter-propagating beams to decelerate the atoms and hold them in a three-dimensional optical trap in vacuum. Typically, these trapping/cooling beams are linearly polarized and are positioned and oriented so that (1) counter-propagating beams in each pair have opposite linear polarizations and (2) three of the six orthogonal beams have the sum of their propagation directions pointing up, while the other three have the sum of their propagation directions pointing down. In a typical prior design, two lasers are used - one to generate the three "up" beams, the other to generate the three "down" beams. For this purpose, the output of each laser is split three ways, then the resulting six beams are delivered to the vacuum system, independently of each other, via optical fibers. The present recirculating design also requires two lasers, but the beams are not split before delivery. Instead, only one "up" beam and one oppositely polarized "down" beam are delivered to the vacuum system, and each of these beams is sent through the collection region three times. The polarization of each beam on each pass through the collection region is set up to yield the same combination of polarization and propagation directions as described above. In comparison with the prior design, the present recirculating design utilizes the available laser light more efficiently, making it possible to trap more atoms at a given laser power or the same number of atoms at a lower laser power. The present design is also simpler in that it requires fewer optical fibers, fiber couplings, and collimators, and fewer photodiodes for monitoring beam powers. Additionally, the present design alleviates the difficulty of maintaining constant ratios among power levels of the beams within each "up" or "down" triplet.

Enzer, Daphna G.; Klipstein, WIlliam M.; Moore, James D.

2007-01-01

313

Experiments With Recirculating Target for F-18 Production  

NASA Astrophysics Data System (ADS)

Approximately 10 ml of O-18 water was loaded in an apparatus containing a 5 ml storage vessel, pump, silver target attached to a cyclotron, filter, backpressure regulator, conductivity meter, several valves and ion exchange cartridges. The water was continuously pumped through the target during proton bombardment at a rate 5 ml/min. Continuous irradiation with beam current ranging from 10 to 50 uA was conducted while pressure, temperature and conductivity were continuously monitored. The results indicate that recirculating of the target water can increase production of F-18 in relation to consumed O-18 water material. It can also increase productivity by eliminating idle periods for re-filling the target. A backpressure regulator can precisely control target pressure. This method also allows for continuous monitoring of the target material temperature, pressure, conductivity and accumulated radioactivity. Results of these observations provide important information about target performance and physical processes taking place inside the target.

Kiselev, M. Y.

2003-08-01

314

Experiments With Recirculating Target for F-18 Production  

SciTech Connect

Approximately 10 ml of O-18 water was loaded in an apparatus containing a 5 ml storage vessel, pump, silver target attached to a cyclotron, filter, backpressure regulator, conductivity meter, several valves and ion exchange cartridges. The water was continuously pumped through the target during proton bombardment at a rate 5 ml/min. Continuous irradiation with beam current ranging from 10 to 50 uA was conducted while pressure, temperature and conductivity were continuously monitored. The results indicate that recirculating of the target water can increase production of F-18 in relation to consumed O-18 water material. It can also increase productivity by eliminating idle periods for re-filling the target. A backpressure regulator can precisely control target pressure. This method also allows for continuous monitoring of the target material temperature, pressure, conductivity and accumulated radioactivity. Results of these observations provide important information about target performance and physical processes taking place inside the target.

Kiselev, M.Y. [Eastern Isotopes, Inc. Sterling, VA (United States)

2003-08-26

315

WATER DISTRIBUTION SYSTEM OPERATION: APPLICATION OF  

E-print Network

CHAPTER 5 WATER DISTRIBUTION SYSTEM OPERATION: APPLICATION OF SIMULATED ANNEALING Fred E. Goldman Arizona State University, Tempe, Arizona 5.1 INTRODUCTION The operation of water distribution systems affects the water quality in these systems. EPA regulations require that water quality be maintained

Mays, Larry W.

316

Total Water Management, the New Paradigm for Urban Water Systems  

EPA Science Inventory

There is a growing need for urban water managers to take a more holistic view of their water resource systems as population growth, urbanization, and current resource management practices put different stresses on local water resources and urban infrastructure. Total Water Manag...

317

Water monitor system: Phase 1 test report  

NASA Technical Reports Server (NTRS)

Automatic water monitor system was tested with the objectives of assuring high-quality effluent standards and accelerating the practice of reclamation and reuse of water. The NASA water monitor system is described. Various components of the system, including the necessary sensors, the sample collection system, and the data acquisition and display system, are discussed. The test facility and the analysis methods are described. Test results are reviewed, and recommendations for water monitor system design improvement are presented.

Taylor, R. E.; Jeffers, E. L.

1976-01-01

318

Water system modeling for dispatcher training simulators  

SciTech Connect

This paper addresses the existing need for training dispatchers in the operation of power systems where it involves managing large water systems. The problem formulation and implementation of water system modeling for the Dispatcher Training Simulators (DTS) are presented in this paper. The method systematically builds the water network descriptions. The model periodically calculates the water system flows, storage values, and currently available hydro generation capacities. The model is controllable by the instructor and provides the simulated telemetry of water system data to the control center functions in the DTS. The water system modeling enhances the power system modeling subsystem of the DTS. The method is validated on a large water system and power system data. The results and the benefits of water system modeling are discussed.

Rajagopal, S.; Sigari, P.G. (Empros Systems International, Minneapolis, MN (United States)); Allen, J.E.; Assadian, M. (Pacific Gas and Electric, San Francisco, CA (United States))

1993-08-01

319

Recirculating sprayer for fiber-filled paints  

NASA Technical Reports Server (NTRS)

Recirculating paint sprayer applies spray of coarse filler in highly volatile solvent. Sprayer was developed for applying insulation material containing epxoy resin, glass fibers, and inert fillers suspended in chlorinated solvents. Sprayer resists abrasive action of fiberglass filler and chemical activity of solvent. Pump and position ensure more uniform pressure at spray gun without backpressure regulator, which tended to clog in old sprayer.

Major, R. K.

1980-01-01

320

Water: Life's Elixir in the Solar System  

NSDL National Science Digital Library

This article discusses the possible occurrence of water in our solar system. Topics include the necessity of liquid water for life, distribution of water throughout the solar system, and the possibility that there may be liquid water on Mars or on some of Jupiter's moons.

321

Three simple culture devices for aquatic invertebrates and fish larvae with continuous recirculation of the medium  

Microsoft Academic Search

The 3 culturing devices described are based on the principle of the classic air-water lift, which facilitates continuous recirculation and aeration of the cultivation medium. The first device is a “circulation cylinder”, convenient for hatching eggs of the brine shrimp Artemia salina and for culturing algae and protozoans. In the second device, an internal basket (i.e., a glass cylinder with

P. Sorgeloos; G. Persoone

1972-01-01

322

Water reactive hydrogen fuel cell power system  

SciTech Connect

A water reactive hydrogen fueled power system includes devices and methods to combine reactant fuel materials and aqueous solutions to generate hydrogen. The generated hydrogen is converted in a fuel cell to provide electricity. The water reactive hydrogen fueled power system includes a fuel cell, a water feed tray, and a fuel cartridge to generate power for portable power electronics. The removable fuel cartridge is encompassed by the water feed tray and fuel cell. The water feed tray is refillable with water by a user. The water is then transferred from the water feed tray into the fuel cartridge to generate hydrogen for the fuel cell which then produces power for the user.

Wallace, Andrew P; Melack, John M; Lefenfeld, Michael

2014-11-25

323

Water reactive hydrogen fuel cell power system  

DOEpatents

A water reactive hydrogen fueled power system includes devices and methods to combine reactant fuel materials and aqueous solutions to generate hydrogen. The generated hydrogen is converted in a fuel cell to provide electricity. The water reactive hydrogen fueled power system includes a fuel cell, a water feed tray, and a fuel cartridge to generate power for portable power electronics. The removable fuel cartridge is encompassed by the water feed tray and fuel cell. The water feed tray is refillable with water by a user. The water is then transferred from the water feed tray into a fuel cartridge to generate hydrogen for the fuel cell which then produces power for the user.

Wallace, Andrew P; Melack, John M; Lefenfeld, Michael

2014-01-21

324

A silver ion water sterilization system  

NASA Technical Reports Server (NTRS)

Small amounts of silver are incorporated in mixture of ion exchange resins, and water passing through this mixture is thus exposed to silver ion concentration. System is useful in self-contained water systems except city water systems where residual chlorine level is stipulated.

Parry, E. P.

1971-01-01

325

Effect of automatic recirculation flow control on the transient response for Lungmen ABWR plant  

Microsoft Academic Search

In this study the automatic mode of the recirculation flow control system (RFCS) for the Lungmen ABWR plant has been modeled and incorporated into the basic RETRAN-02 system model. The integrated system model is then used to perform the analyses for the two transients in which the automatic RFCS is involved. The two transients selected are: (1) one reactor internal

Yih-Chyun Tzang; Ray-Feng Chiang; Yuh-Ming Ferng; Bau-Shei Pei

2009-01-01

326

Method and an apparatus for biological treatment of waste waters  

SciTech Connect

A waste water treatment plant providing biological oxidation, biological nitrification and denitrification and biological removal of phosphorus and clarification of the treated waste water in a single reaction tank in a single suspended growth sludge system without the use of the traditional compressors, surface aerators, mixers, recirculation pumps, sludge scrapers, sludge return pumps, piping and valving.

Besik, F.

1982-10-12

327

Electroporation System for Sterilizing Water  

NASA Technical Reports Server (NTRS)

A prototype of an electroporation system for sterilizing wastewater or drinking water has been developed. In electroporation, applied electric fields cause transient and/or permanent changes in the porosities of living cells. Electroporation at lower field strengths can be exploited to increase the efficiency of chemical disinfection (as in chlorination). Electroporation at higher field strengths is capable of inactivating and even killing bacteria and other pathogens, without use of chemicals. Hence, electroporation is at least a partial alternative to chlorination. The transient changes that occur in micro-organisms at lower electric-field strengths include significantly increased uptake of ions and molecules. Such increased uptake makes it possible to achieve disinfection at lower doses of chemicals (e.g., chlorine or ozone) than would otherwise be needed. Lower doses translate to lower costs and reduced concentrations of such carcinogenic chemical byproducts as trichloromethane. Higher electric fields cause cell membranes to lose semipermeability and thereby become unable to function as selective osmotic barriers between the cells and the environment. This loss of function is the cause of the cell death at higher electric-field intensities. Experimental evidence does not indicate cell lysis but, rather, combined leaking of cell proteins out of the cells as well as invasion of foreign chemical compounds into the cells. The concept of electroporation is not new: it has been applied in molecular biology and genetic engineering for decades. However, the laboratory-scale electroporators used heretofore have been built around small (400-microliter) cuvettes, partly because the smallness facilitates the generation of electric fields of sufficient magnitude to cause electroporation. Moreover, most laboratory- scale electroporators have been designed for testing static water. In contrast, the treatment cell in the present system is much larger and features a flow-through geometry, such that electric fields strong enough to effect 99.9- percent disinfection can be applied to water flowing in a pipe.

Schlager, Kenneth J.

2005-01-01

328

The influence of different electrical conductivity values in a simplified recirculating soilless system on inner and outer fruit quality characteristics of tomato.  

PubMed

Irrigation with saline water affects tomato fruit quality. While total fruit yield decreases with salinity, inner quality characterized by taste and health-promoting compounds can be improved. For a detailed description of this relationship, the influence of three different salt levels [electrical conductivity (EC) 3, 6.5, and 10] in hydroponically grown tomatoes was investigated. Rising salinity levels in the nutrient solution significantly increased vitamin C, lycopene, and beta-carotene in fresh fruits up to 35%. The phenol concentration was tendentiously enhanced, and the antioxidative capacity of phenols and carotenoids increased on a fresh weight basis. Additionally, the higher EC values caused an increase of total soluble solids and organic acids, parameters determining the taste of tomatoes. Total fruit yield, single fruit weight, and firmness significantly decreased with rising EC levels. Regression analyses revealed significant correlations between the EC level and the dependent variables single fruit weight, total soluble solids, titrable acids, lycopene, and antioxidative capacities of carotenoids and phenols, whereas vitamin C and phenols correlated best with truss number, and beta-carotene correlated best with temperature. Only pressure firmness showed no correlation with any of the measured parameters. As all desirable characteristics in the freshly produced tomato increased when exposed to salinity, salinity itself constitutes an alternative method of quality improvement. Moreover, it can compensate for the loss of yield by the higher inner quality due to changing demands by the market and the consumer. This investigation is to our knowledge the first comprehensive overview regarding parameters of outer quality (yield and firmness), taste (total soluble solids and acids), nutritional value (vitamin C, carotenoids, and phenolics), as well as antioxidative capacity in tomatoes grown under saline conditions. PMID:16417302

Krauss, Sandra; Schnitzler, Wilfried H; Grassmann, Johanna; Woitke, Markus

2006-01-25

329

A 200 MeV Recirculating LINAC as an Injector for the LNLS UVX Electron Storage Ring  

Microsoft Academic Search

The design of an isochronous recirculating system to double the injection energy (from 100 to 200 MeV) of the LNLS UVX electron storage ring is dcscribcd. The system is composed of a gun-to-LINAC transport line, four 3-meter long SLAC-type traveling wave sections, which accelerate the beam to 100 MeV, and an isochronous recirculating line which reinjects the beam into the

R. H. A. Farias; L. Jahnel; L. Lin; P. F. Tavares

330

Chaotic mixing in a microchannel utilizing periodically switching electro-osmotic recirculating rolls  

NASA Astrophysics Data System (ADS)

In this study, active mixing in a microchannel with spatiotemporal variations in ? potential distributions was investigated theoretically. In this mixing system, the primary flow is a pressure-driven flow (i.e., parabolic flow), and the electro-osmotic recirculating rolls induced by the heterogeneous ? potential distributions act as the perturbation source. By timewise alterations of two different electro-osmotic recirculating flow fields, chaotic mixing can be induced. Blob deformation, Poincaré map, and Lyapunov exponent analyses were employed to describe the behaviors of the particle motion in this active mixing system. Finally, the optimal time-switching period was identified, which was also verified through direct numerical simulations.

Chang, Chih-Chang; Yang, Ruey-Jen

2008-05-01

331

Hybrid heat exchange for the compression capture of CO2 from recirculated flue gas  

SciTech Connect

An approach proposed for removal of CO2 from flue gas cools and compresses a portion of a recirculated flue-gas stream, condensing its volatile materials for capture. Recirculating the flue gas concentrates SOx, H2O and CO2 while dramatically reducing N2 and NOx, enabling this approach, which uses readily available industrial components. A hybrid system of indirect and direct-contact heat exchange performs heat and mass transfer for pollutant removal and energy recovery. Computer modeling and experimentation combine to investigate the thermodynamics, heat and mass transfer, chemistry and engineering design of this integrated pollutant removal (IPR) system.

Oryshchyn, Danylo B.; Ochs, Thomas L.; Summers, Cathy A.

2004-01-01

332

Sustainable Water Use System of Artesian Water in Alluvial Fan  

NASA Astrophysics Data System (ADS)

The traditional water use system, developed with the intelligence of the local residents, usually takes advantage of local natural resources and is considered as a sustainable system, because of its energy saving(only forces of nature). For this reason, such kind of water use system is also recommended in some strategic policies for the purpose of a symbiosis between nature and human society. Therefore, it is important to clarify the relationship between human activities and water use systems. This study aims to clarify the mechanism of traditional water use processes in alluvial fan, and in addition, to investigate the important factors which help forming a sustainable water use system from the aspects of natural conditions and human activities. The study area, an alluvial fan region named Adogawa, is located in Shiga Prefecture, Japan and is in the west of Biwa Lake which is the largest lake in Japan. In this alluvial region where the land use is mainly occupied by settlements and paddy fields, a groundwater flowing well system is called "kabata" according to local tradition. During field survey, we took samples of groundwater, river water and lake water as well as measured the potential head of groundwater. The results showed that the upper boundary of flowing water was approximately 88m amsl, which is basically the same as the results reported by Kishi and Kanno (1966). In study area, a rapid increase of water pumping for domestic water use and melting snow during last 50 years, even if the irrigation area has decreased about 30% since 1970, and this fact may cause a decrease in recharge rate to groundwater. However, the groundwater level didn't decline based on the observed results, which is probably contributed by some water conservancy projects on Biwa Lake which maintained the water level of the lake. All the water samples are characterized by Ca-HCO3 type and similar stable isotopic value of ?D and ?18O. Groundwater level in irrigation season is higher than that in non-irrigation season, which indicates that groundwater level is apparently influenced by surface water. Some communities and NPOs working in this area maintain the "kabata" and canal for environment conservation. There are many rules for the local residents when using the water resources. For example, the use of detergents is prohibited for "kabata" users. The residents living upstream also should think of other groundwater users downstream. For this reason, it can be considered that the "kabata" water use method contributed to a symbiosis between ecosystem and human activity The study area case showed that the traditional water use system is useful for forming a sustainable groundwater flowing well use system.

Kishi, K.; Tsujimura, M.; Tase, N.

2013-12-01

333

Beneficial effects on water management of simple hydraulic structures in wetland systems: the Vallevecchia case study, Italy.  

PubMed

Conflicting water uses in coastal zones demand integrated approaches to achieve sustainable water resources management, protecting water quality while allowing those human activities which rely upon aquatic ecosystem services to thrive. This case study shows that the creation and simple management of hydraulic structures within constructed wetlands can markedly reduce the non-point pollution from agriculture and, simultaneously, benefit agricultural activities, particularly during hot and dry periods. The Vallevecchia wetland system is based on a reclaimed 900 ha-large drainage basin in Northern Italy, where droughts recently impacted agriculture causing water scarcity and saltwater intrusion. Rainwater and drained water are recirculated inside the system to limit saltwater intrusion, provide irrigation water during dry periods and reduce the agricultural nutrient loads discharged into the bordering, eutrophic Adriatic Sea. Monitoring (2003-2009) of water quality and flows highlights that the construction (ended in 2005) of a gated spillway to control the outflow, and of a 200,000 m3 basin for water storage, dramatically increased the removal of nutrients within the system. Strikingly, this improvement was achieved with a minimal management effort, e.g., each year the storage basin was filled once: a simple management of the hydraulic structures would greatly enhance the system efficiency, and store more water to irrigate and limit saltwater intrusion. PMID:22053478

Carrer, G M; Bonato, M; Smania, D; Barausse, A; Comis, C; Palmeri, L

2011-01-01

334

Purification of Aquacultural Water: Conventional and New Membrane-based Techniques  

Microsoft Academic Search

Removing solids is an essential task when recirculating water an aquaculture system. Dissolved solids production directly from particulate solids as well as by fish is a function of time. These contaminants can indirectly affect the fish both biologically and physically. The flaws of conventional water treatment on seawater aquaculture systems are reviewed in this paper. Then a new technology for

Rosalam Sarbatly

2011-01-01

335

High Power Picosecond Laser Pulse Recirculation  

SciTech Connect

We demonstrate a nonlinear crystal-based short pulse recirculation cavity for trapping the second harmonic of an incident high power laser pulse. This scheme aims to increase the efficiency and flux of Compton-scattering based light sources. We demonstrate up to 36x average power enhancement of frequency doubled sub-millijoule picosecond pulses, and 17x average power enhancement of 177 mJ, 10 ps, 10 Hz pulses.

Shverdin, M Y; Jovanovic, I; Semenov, V A; Betts, S M; Brown, C; Gibson, D J; Shuttlesworth, R M; Hartemann, F V; Siders, C W; Barty, C P

2010-04-12

336

DETERIORATION OF DRINKING WATER DISTRIBUTION SYSTEMS  

EPA Science Inventory

A frequently overlooked fact, but one that is becoming of increasing concern, is the effect that the drinking water delivery system can have on the quality of water received at the tap. Deterioration of aging water supply systems can result in pipeline failures, pressure losses, ...

337

Information Sources for Small Water Systems  

E-print Network

E - 4 3 8 0 2 - 0 7 ?The protection of water quality is vital for managers of small water systems.? Information S o urces for Small Water System s Monty Dozier, Associate Professor and Extension Specialist; Gene Theodori, Associate Professor...

Dozier, Monty; Theodori, Gene L.; Jensen, Ricard

2007-02-19

338

Combined air and water pollution control system  

NASA Technical Reports Server (NTRS)

A bioaquatic air pollution control system for controlling both water and atmospheric pollution is disclosed. The pollution control system includes an exhaust for directing polluted gases out of a furnace and a fluid circulating system which circulates fluid, such as waste water, from a source, past the furnace where the fluid flow entrains the pollutants from the furnace. The combined fluid and pollutants are then directed through a rock/plant/microbial filtering system. A suction pump pumps the treated waste water from the filter system past the exhaust to again entrain more pollutants from the furnace where they are combined with the fluid (waste water) and directed to the filter system.

Wolverton, Billy C. (inventor); Jarrell, Lamont (inventor)

1990-01-01

339

Disinfecting Filters For Recirculated Air  

NASA Technical Reports Server (NTRS)

Simple treatment disinfects air filters by killing bacteria, algae, fungi, mycobacteria, viruses, spores, and any other micro-organisms filters might harbor. Concept applied to reusable stainless-steel wire mesh filters and disposable air filters. Treatment used on filters in air-circulation systems in spacecraft, airplanes, other vehicles, and buildings to help prevent spread of colds, sore throats, and more-serious illnesses.

Pilichi, Carmine A.

1992-01-01

340

An Oil/Water disperser device for use in an oil content Monitor/Control system  

NASA Astrophysics Data System (ADS)

This patent application discloses an oil content monitor/control unit system, including an oil/water disperser device, which is configured to automatically monitor and control processed effluent from an associated oil/water separator so that if the processed effluent exceeds predetermine in-port or at-sea oil concentration lmits, it is either recirculated to an associated oil/water separator via a ship's bilge for additional processing, or diverted to a holding tank for storage. On the other hand, if the oil concentration of the processed effluent is less than predetermine in-port or at-sea limits, it is discharged overboard. The oil/water disperser device is configured to break up any oil present in the processed effluent into uniform droplets for more accurate sensing of the oil present in the processed effluent into uniform droplets for more accurate sensing of the oil-in-water concentration level thereof. The oil/water disperser device has a flow-actuated variable orifice configured into a spring-loaded polyethylene plunger which provides the uniform distribution of oil droplets.

Kempel, F. D.

1985-07-01

341

Mining Gold from your Cooling Water System  

E-print Network

Mining Gold from your Cooling Water System Tino Mendez Director Energy Engineering The Benham Companies, LLC Oklahoma City, Oklahoma ABSTRACT You may be missing on a fabulous opportunity to save on operating costs in your cooling water...

Mendez, T.

342

Corrosion control in water injection systems  

SciTech Connect

Corrosion control in water injection systems encompasses a wide range of technologies, including chemicals (corrosion inhibitors, biocides, and oxygen scavengers); corrosion-resistant materials (metallic and nonmetallic); internal coatings and linings; mechanical removal of dissolved oxygen; velocity control; and prevention of oxygen entry and galvanic couples. This article reviews the way that these technologies are used in modern water-injection systems (both seawater and produced water) to provide an acceptable service life and high-quality injection water.

Patton, C.C. (C.C. Patton and Associates Inc., Dallas, TX (United States))

1993-08-01

343

INDUSTRIAL WASTEWATER RECIRCULATION SYSTEM: PRELIMINARY ENGINEERING  

EPA Science Inventory

The report details the preliminary engineering work done at Owens-Corning's (O-C's) Anderson, South Carolina, fibrous glass plant. The purpose of the work was to test, on a pilot plant scale, various technologies to be used to clean up industrial wastewater for a closed-loop syst...

344

PILOT SCALE WATER REUSE SYSTEM  

EPA Science Inventory

The efficiency of the treatment technologies is expected to vary with the source water quality. By testing the technologies with various source waters, the research will quantify the limits of the technology: testing the flow rate variations with influent water quality, evalu...

345

Automated liquid-liquid extraction by pneumatic recirculation on a centrifugal microfluidic platform.  

PubMed

In this technical note, a liquid-liquid extraction technique was performed using pneumatic liquid recirculation on a centrifugal microfluidic device. Non-contact pneumatic pumping enabled a multi-cycle liquid-liquid extraction process using aqueous iodine in a potassium iodide solution and hexadecane while requiring a minimal amount of space on the device. The extraction process was completely automated on the device following sample introduction and required only 50 s for each extraction cycle. The pumping rate achieved during liquid recirculation was 120 ± 10 ?L/min. A recycling process such as the one demonstrated would be difficult to implement in a conventional centrifugal microfluidic system. PMID:22845877

Kazarine, Alexei; Kong, Matthew C R; Templeton, Erin J; Salin, Eric D

2012-08-21

346

Urban water supply distributed control system  

Microsoft Academic Search

The rapid growing of the wide urban residential areas imposes the expansion as well as the modernization of the existing water supply facilities. Process automation system based upon utilization of an industrial PLC and PC systems including all the network components represents the best way to improve the water distribution technological process. The system includes remote terminal units - RTU,

E. Stancel; I. Stoian; I. Kovacs; B. Z. Gyurka; S. Balogh

2008-01-01

347

SAFE DRINKING WATER INFORMATION SYSTEM (STATE)  

EPA Science Inventory

Resource Purpose: The Safe Drinking Water Information System (STATE) (SDWIS/STATE) is an information system OGWDW is developing for states and EPA regions to manage their water industry. SDWIS/STATE is not an information system for which EPA HQ is using to store or retrie...

348

Space shuttle galley water system test program  

NASA Technical Reports Server (NTRS)

A water system for food rehydration was tested to determine the requirements for a space shuttle gallery flight system. A new food package concept had been previously developed in which water was introduced into the sealed package by means of a needle and septum. The needle configuration was developed and the flow characteristics measured. The interface between the food package and the water system, oven, and food tray was determined.

1975-01-01

349

A Synergistic Combination of Advanced Separation and Chemical Scale Inhibitor Technologies for Efficient Use of Imparied Water As Cooling Water in Coal-based Power Plants  

Microsoft Academic Search

Nalco Company is partnering with Argonne National Laboratory (ANL) in this project to jointly develop advanced scale control technologies that will provide cost-effective solutions for coal-based power plants to operate recirculating cooling water systems at high cycles using impaired waters. The overall approach is to use combinations of novel membrane separations and scale inhibitor technologies that will work synergistically, with

Jasbir Gill

2010-01-01

350

Influence of gas velocity on particulate fouling of exhaust gas recirculation coolers  

Microsoft Academic Search

The objective of this research is to study the influence of gas flow velocity on particulate fouling of exhaust gas recirculation (EGR) coolers. An experimental setup has been designed and constructed to simulate particulate fouling in EGR coolers in diesel engines. The setup consists of soot generator, gas\\/particle flow heater, testing section for EGR coolers and finally an exhaust system.

M. S. Abd-Elhady; T. Zornek; M. R. Malayeri; S. Balestrino; P. G. Szymkowicz; H. Müller-Steinhagen

2011-01-01

351

Apollo experience report: Potable water system  

NASA Technical Reports Server (NTRS)

A description of the design and function of the Apollo potable water system is presented. The command module potable water is supplied as a byproduct of the fuel cells. The cells, located in the service module, function primarily to supply electrical energy to the spacecraft. The source of the lunar module potable water is three tanks, which are filled before lift-off. The technique of supplying the water in each of these cases and the problems associated with materials compatibility are described. The chemical and microbiological quality of the water is reviewed, as are efforts to maintain the water in a microbially safe condition for drinking and food mixing.

Sauer, R. L.; Calley, D. J.

1973-01-01

352

Exhaust gas recirculation in a homogeneous charge compression ignition engine  

DOEpatents

A homogeneous charge compression ignition engine operates by injecting liquid fuel directly in a combustion chamber, and mixing the fuel with recirculated exhaust and fresh air through an auto ignition condition of the fuel. The engine includes at least one turbocharger for extracting energy from the engine exhaust and using that energy to boost intake pressure of recirculated exhaust gas and fresh air. Elevated proportions of exhaust gas recirculated to the engine are attained by throttling the fresh air inlet supply. These elevated exhaust gas recirculation rates allow the HCCI engine to be operated at higher speeds and loads rendering the HCCI engine a more viable alternative to a conventional diesel engine.

Duffy, Kevin P. (Metamora, IL); Kieser, Andrew J. (Morton, IL); Rodman, Anthony (Chillicothe, IL); Liechty, Michael P. (Chillicothe, IL); Hergart, Carl-Anders (Peoria, IL); Hardy, William L. (Peoria, IL)

2008-05-27

353

Recirculating Linear Accelerators for Future Muon Facilities  

SciTech Connect

Neutrino Factories (NF) and Muon Colliders (MC) require rapid acceleration of short-lived muons to multi-GeV and TeV energies. A Recirculating Linear Accelerator (RLA) that uses superconducting RF structures can provide exceptionally fast and economical acceleration to the extent that the focusing range of the RLA quadrupoles allows each muon to pass several times through each high-gradient cavity. A new concept of rapidly changing the strength of the RLA focusing quadrupoles as the muons gain energy is being developed to increase the number of passes that each muon will make in the RF cavities, leading to greater cost effectiveness.

S.A. Bogacz, K.B.Beard, R.P. Johnson

2010-05-01

354

Economic Representation of Agricultural Activities in Water Resources Systems Engineering  

E-print Network

i Economic Representation of Agricultural Activities in Water Resources Systems Engineering Representation of Agricultural Activities in Water Resources Systems Engineering Abstract Water demands reflect

Lund, Jay R.

355

NASA's Plum Brook Station Water Systems  

NASA Technical Reports Server (NTRS)

Plum Brook Station's water systems were built in the 1940s to support a World War II ordnance production complex. Because the systems had not been analyzed for current NASA usage, it was unknown if they could meet current requirements and codes or if they were efficient for current use. NASA wanted to determine what improvements would be needed or advisable to support its research projects, so it contracted a hydraulic analysis of the raw and domestic water systems. Burgess and Niple determined current water demands and water flow, developed and calibrated models of the two water systems, and evaluated efficiency improvements and cost-cutting options. They recommended replacing some water mains, installing a new service connection, and removing some high-maintenance items (an underground reservoir, some booster pumps, and a tower).

Puzak, Robert M.; Kimpton, Arthur

2006-01-01

356

Seaweed biofilters as regulators of water quality in integrated fish-seaweed culture units  

Microsoft Academic Search

The water-quality characteristics of a new system for the integrated culture of fish (Sparus aurata L.) and seaweed (Ulva lactuca L.) were examined. Seawater was recirculated between intensive fishponds and seaweed ponds. The seaweed removed most of the ammonia excreted by the fish and oxygenated the water. A model consisting of several tanks and a pilot consisting of two 100-m3,

Amir Neori; Michael D. Krom; Steve P. Ellner; Claude E. Boyd; Dan Popper; Ruth Rabinovitch; Patrick J. Davison; Orit Dvir; Daniel Zuber; Michal Ucko; Dror Angel; Hillel Gordin

1996-01-01

357

GPR-Based Water Leak Models in Water Distribution Systems  

PubMed Central

This paper addresses the problem of leakage in water distribution systems through the use of ground penetrating radar (GPR) as a nondestructive method. Laboratory tests are performed to extract features of water leakage from the obtained GPR images. Moreover, a test in a real-world urban system under real conditions is performed. Feature extraction is performed by interpreting GPR images with the support of a pre-processing methodology based on an appropriate combination of statistical methods and multi-agent systems. The results of these tests are presented, interpreted, analyzed and discussed in this paper.

Ayala-Cabrera, David; Herrera, Manuel; Izquierdo, Joaquín; Ocaña-Levario, Silvia J.; Pérez-García, Rafael

2013-01-01

358

21 CFR 1250.42 - Water systems; constant temperature bottles.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 false Water systems; constant temperature bottles. 1250.42 Section 1250...1250.42 Water systems; constant temperature bottles. (a) The water system...contamination of the water. (e) Constant temperature bottles and other containers used...

2011-04-01

359

21 CFR 1250.42 - Water systems; constant temperature bottles.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Water systems; constant temperature bottles. 1250.42 Section 1250...1250.42 Water systems; constant temperature bottles. (a) The water system...contamination of the water. (e) Constant temperature bottles and other containers used...

2010-04-01

360

21 CFR 1250.42 - Water systems; constant temperature bottles.  

...2014-04-01 false Water systems; constant temperature bottles. 1250.42 Section 1250...1250.42 Water systems; constant temperature bottles. (a) The water system...contamination of the water. (e) Constant temperature bottles and other containers used...

2014-04-01

361

21 CFR 1250.42 - Water systems; constant temperature bottles.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Water systems; constant temperature bottles. 1250.42 Section 1250...1250.42 Water systems; constant temperature bottles. (a) The water system...contamination of the water. (e) Constant temperature bottles and other containers used...

2013-04-01

362

High speed exhaust gas recirculation valve  

DOEpatents

In order to minimize pollutants such as Nox, internal combustion engines typically include an exhaust gas recirculation (EGR) valve that can be used to redirect a portion of exhaust gases to an intake conduit, such as an intake manifold, so that the redirected exhaust gases will be recycled. It is desirable to have an EGR valve with fast-acting capabilities, and it is also desirable to have the EGR valve take up as little space as possible. An exhaust gas recirculation valve is provided that includes an exhaust passage tube, a valve element pivotally mounted within the exhaust passage tube, a linear actuator; and a gear train. The gear train includes a rack gear operatively connected to the linear actuator, and at least one rotatable gear meshing with the rack gear and operatively connected to the valve element to cause rotation of the valve element upon actuation of the linear actuator. The apparatus provides a highly compact package having a high-speed valve actuation capability.

Fensom, Rod (Peterborough, GB); Kidder, David J. (Peterborough, GB)

2005-01-18

363

Submersible purification system for radioactive water  

SciTech Connect

A portable, submersible water purification system for use in a pool of water containing radioactive contamination includes a prefilter for filtering particulates from the water. A resin bed is then provided for removal of remaining dissolved, particulate, organic, and colloidal impurities from the prefiltered water. A sterilizer then sterilizes the water. The prefilter and resin bed are suitably contained and are submerged in the pool. The sterilizer is water tight and located at the surface of the pool. The water is circulated from the pool through the prefilter, resin bed, and sterilizer by suitable pump or the like. In the preferred embodiment, the resin bed is contained within a tank which stands on the bottom of the pool and to which a base mounting the prefilter and pump is attached. An inlet for the pump is provided adjacent the bottom of the pool, while the sterilizer and outlet for the system is located adjacent the top of the pool.

Abbott, Michael L. (Fort Collins, CO); Lewis, Donald R. (Pocatello, ID)

1989-01-01

364

A water quality monitoring system for HAWC  

NASA Astrophysics Data System (ADS)

HAWC (High Altitude Water Cherenkov), is a gamma ray (?) large aperture observatory with high sensitivity that will be able to continuously monitor the sky for transient sources of photons with energies between 100 GeV and 100 TeV. HAWC is under construction in Sierra Negra, Puebla, Mexico, which is located at a high altitude of 4100m. HAWC will be an array of 300 Cherenkov detectors each one with 200,000 liters of highly pure water. The sensitivity of the instrument depends strongly on the water quality. We present the design and construction of the HAWC water quality monitoring system. We seek monitor the transparency in violet-blue range to achieve and maintain the required water transparency quality in each detector. The system is robust and user friendly. The measurements are reproducible. Also we present some results from the monitoring the water from the VAMOS detector tanks and of the filtering system.

Garfias, F.; Bernal, A.; Tinoco, S.; Iriarte, A.

2012-09-01

365

Water turbine system and method of operation  

DOEpatents

A system for providing electrical power from a current turbine is provided. The system includes a floatation device and a mooring. A water turbine structure is provided having an upper and lower portion wherein the lower portion includes a water fillable chamber. A plurality of cables are used to couple the system where a first cable couples the water turbine to the mooring and a second cable couples the floatation device to the first cable. The system is arranged to allow the turbine structure to be deployed and retrieved for service, repair, maintenance and redeployment.

Costin, Daniel P. (Montpelier, VT)

2011-05-10

366

The effect of sludge recirculation rate on a UASB-digester treating domestic sewage at 15 °C.  

PubMed

The anaerobic treatment of low strength domestic sewage at low temperature is an attractive and important topic at present. The upflow anaerobic sludge bed (UASB)-digester system is one of the anaerobic systems to challenge low temperature and concentrations. The effect of sludge recirculation rate on a UASB-digester system treating domestic sewage at 15 °C was studied in this research. A sludge recirculation rate of 0.9, 2.6 and 12.5% of the influent flow rate was investigated. The results showed that the total chemical oxygen demand (COD) removal efficiency rose with increasing sludge recirculation rate. A sludge recirculation rate of 0.9% of the influent flow rate led to organic solids accumulation in the UASB reactor. After the sludge recirculation rate increased from 0.9 to 2.6%, the stability of the UASB sludge was substantially improved from 0.37 to 0.15 g CH?-COD/g COD, and the bio-gas production in the digester went up from 2.9 to 7.4 L/d. The stability of the UASB sludge and bio-gas production in the digester were not significantly further improved by increasing sludge recirculation rate to 12.5% of the influent flow rate, but the biogas production in the UASB increased from 0.37 to 1.2 L/d. It is recommended to apply a maximum sludge recirculation rate of 2-2.5% of the influent flow rate in a UASB-digester system, as this still allows energy self-sufficiency of the system. PMID:23109575

Zhang, Lei; Hendrickx, Tim L G; Kampman, Christel; Zeeman, Grietje; Temmink, Hardy; Li, Weiguang; Buisman, Cees J N

2012-01-01

367

Screening reactor steam/water piping systems for water hammer  

SciTech Connect

A steam/water system possessing a certain combination of thermal, hydraulic and operational states, can, in certain geometries, lead to a steam bubble collapse induced water hammer. These states, operations, and geometries are identified. A procedure that can be used for identifying whether an unbuilt reactor system is prone to water hammer is proposed. For the most common water hammer, steam bubble collapse induced water hammer, six conditions must be met in order for one to occur. These are: (1) the pipe must be almost horizontal; (2) the subcooling must be greater than 20 C; (3) the L/D must be greater than 24; (4) the velocity must be low enough so that the pipe does not run full, i.e., the Froude number must be less than one; (5) there should be void nearby; (6) the pressure must be high enough so that significant damage occurs, that is the pressure should be above 10 atmospheres. Recommendations on how to avoid this kind of water hammer in both the design and the operation of the reactor system are made.

Griffith, P. [Massachusetts Inst. of Tech., Cambridge, MA (United States)

1997-09-01

368

Vortex dynamics and scalar transport in the wake of a bluff body driven through a steady recirculating flow  

NASA Astrophysics Data System (ADS)

The air ventilation system in wide-body aircraft cabins provides passengers with a healthy breathing environment. In recent years, the increase in global air traffic has amplified contamination risks by airborne flu-like diseases and terrorist threats involving the onboard release of noxious materials. In particular, passengers moving through a ventilated cabin may transport infectious pathogens in their wake. This paper presents an experimental investigation of the wake produced by a bluff body driven through a steady recirculating flow. Data were obtained in a water facility using particle image velocimetry and planar laser induced fluorescence. Ventilation attenuated the downward convection of counter-rotating vortices produced near the free-end corners of the body and decoupled the downwash mechanism from forward entrainment, creating stagnant contaminant regions.

Poussou, Stephane B.; Plesniak, Michael W.

2012-09-01

369

Wash water waste pretreatment system  

NASA Technical Reports Server (NTRS)

Investigations were completed on wash waters based on each candidate personal cleansing agent. Evaluations of coagulants, antifoam agents, and the effect of promising antifoams on the chemical precipitation were included. Based on these evaluations two candidate soaps as well as their companion antifoam agents were selected for further work. Operating parameters included the effect of soap concentration, ferric chloride concentration, duration of mixing, and pore size of depth filters on the degree of soap removal. The effect of pressure on water flow through filter cartridges and on the rate of decline of water flow was also investigated. The culmination of the program was the recommendation of a pretreatment concept based on chemical precipitation followed by pressure filtration.

1977-01-01

370

Energy savings from air recirculation in peanut curing  

SciTech Connect

A thin-layer peanut drying simulation model was adapted to incorporate air recirculation. Laboratory crop dryers were designed and constructed to conduct experiments to verify the model. Five batches of peanuts were dried using different recirculation strategies. The model successfully predicted the results.

Cook, D.F.; Cundiff, J.S.; Vaughan, D.H.

1982-12-01

371

The potable water system in Skylab  

NASA Technical Reports Server (NTRS)

Description of the medical requirements, development, system operation, and in-flight performance of the Skylab potable water system. Emphasized is the description of the unique features involving new space-flight concepts, procedures, and design incorporated in Skylab. The water supplied to the three Skylab missions was preloaded in stainless-steel tanks. These tanks were fitted with positive expulsion stainless-steel bellows. In-flight iodination of the water, for bacterial control, was accomplished as required. An in-flight bactericide monitor was used periodically to determine the level of bactericide in the water. Prior to the delivery of the water to the crewmen for consumption, the water was passed through a cation exchange resin for metallic ion removal and then heated for food reconstitution or chilled for drinking.

Sauer, R. L.; Westover, J. B.

1974-01-01

372

Integrated waste and water management system  

NASA Technical Reports Server (NTRS)

The performance requirements of the NASA Space Station have prompted a reexamination of a previously developed integrated waste and water management system that used distillation and catalytic oxydation to purify waste water, and microbial digestion and incineration for waste solids disposal. This system successfully operated continuously for 206 days, for a 4-man equivalent load of urine, feces, wash water, condensate, and trash. Attention is given to synergisms that could be established with other life support systems, in the cases of thermal integration, design commonality, and novel technologies.

Murray, R. W.; Sauer, R. L.

1986-01-01

373

Biofilm formation and multiplication of Legionella in a model warm water system with pipes of copper, stainless steel and cross-linked polyethylene.  

PubMed

Legionella pneumophila was grown in a model warm water system with pipes of copper (Cu), stainless steel (SS) and cross-linked polyethylene (PEX) during recirculation of tap water at 25--35 degrees C. Subsequently, domestic use of warm (37 degrees C) water was simulated using tap water with a low AOC concentration (<10 microg C/L). Two times each week the temperature of the water in the electric heaters (not in the pipes) was elevated to 70 degrees C for 30 min. ATP concentrations in the water sampled from the pipes over a 2-year period were significantly different for the pipe materials, with median values of 2.1 ng/l (Cu), 2.5 ng/l (SS) and 4.5 ng/l (PEX), respectively. Median values of the biofilm concentration were similar on Cu and SS (about 630 pg ATP/cm(2)) and 1870 pg ATP/cm(2) on PEX. Legionella multiplied in these biofilms and median values of Legionella concentrations in water were 1500 CFU/l (Cu) and about 4300 CFU/l for SS and PEX. Legionella to ATP ratios in water had median values of about 0.8 CFU/pg. Hot water flushing (70 degrees C) of the pipes on day 552, followed by 2 weeks of recirculation at 37 degrees C, caused strongly increased concentrations of ATP (up to 300 ng/l) and Legionella (>10(7)CFU/l), with about 100 CFU/pg ATP. Concentrations declined to original levels within 1 week of domestic water use, etc. Legionella concentrations in water and biofilms were at the same levels for all materials after 2 years. Hence, copper temporarily limited the growth of Legionella under the applied conditions and a rapid biomass development strongly increased the Legionella to ATP ratio. PMID:16019051

van der Kooij, Dick; Veenendaal, Harm R; Scheffer, Will J H

2005-08-01

374

Spacesuit Water Membrane Evaporator; An Enhanced Evaporative Cooling System for the Advanced Extravehicular Mobility Unit Portable Life Support System  

NASA Technical Reports Server (NTRS)

Development of the Advanced Extravehicular Mobility Unit (AEMU) portable life support subsystem (PLSS) is currently under way at NASA Johnson Space Center. The AEMU PLSS features a new evaporative cooling system, the Generation 4 Spacesuit Water Membrane Evaporator (Gen4 SWME). The SWME offers several advantages when compared with prior crewmember cooling technologies, including the ability to reject heat at increased atmospheric pressures, reduced loop infrastructure, and higher tolerance to fouling. Like its predecessors, Gen4 SWME provides nominal crew member and electronics cooling by flowing water through porous hollow fibers. Water vapor escapes through the hollow fiber pores, thereby cooling the liquid water that remains inside of the fibers. This cooled water is then recirculated to remove heat from the crew member and PLSS electronics. Test results from the backup cooling system which is based on a similar design and the subject of a companion paper, suggested that further volume reductions could be achieved through fiber density optimization. Testing was performed with four fiber bundle configurations ranging from 35,850 fibers to 41,180 fibers. The optimal configuration reduced the Gen4 SWME envelope volume by 15% from that of Gen3 while dramatically increasing the performance margin of the system. A rectangular block design was chosen over the Gen3 cylindrical design, for packaging configurations within the AEMU PLSS envelope. Several important innovations were made in the redesign of the backpressure valve which is used to control evaporation. A twin-port pivot concept was selected from among three low profile valve designs for superior robustness, control and packaging. The backpressure valve motor, the thermal control valve, delta pressure sensors and temperature sensors were incorporated into the manifold endcaps, also for packaging considerations. Flight-like materials including a titanium housing were used for all components. Performance testing of the Gen4 SWME is underway.

Bue, Grant C.; Makinen, Janice V.; Miller, Sean; Campbell, Colin; Lynch, Bill; Vogel, Matt; Craft, Jesse; Wilkes, Robert; Kuehnel, Eric

2014-01-01

375

Water treatment considerations for thermal storage systems  

SciTech Connect

Traditional closed loop corrosion, fouling, and microbial control treatments are not always capable of providing effective treatment to Thermal Energy Storage systems. Typically, these systems experience a higher incidence of corrosion, corrosion related fouling and microbial problems than traditional closed loop applications. Customary corrosion control treatments like nitrite have yielded poor results due to microbial degradation. Microbial control is often harder due to the sheer volume of water needing treatment and inadequate distribution in the system. This paper will review the various water treatment needs for Thermal Energy Storage Systems and present data on a successfully operating Thermal Energy Storage system.

Meier, D.A. [Nalco Chemical Co., Naperville, IL (United States)

1998-12-31

376

Nutrient Management in Recirculating Hydroponic Culture  

NASA Technical Reports Server (NTRS)

There is an increasing need to recirculate and reuse nutrient solutions in order to reduce environmental and economic costs. However, one of the weakest points in hydroponics is the lack of information on managing the nutrient solution. Many growers and research scientists dump out nutrient solutions and refill at weekly intervals. Other authors have recommended measuring the concentrations of individual nutrients in solution as a key to nutrient control and maintenance. Dumping and replacing solution is unnecessary. Monitoring ions in solution is not always necessary; in fact the rapid depletion of some nutrients often causes people to add toxic amounts of nutrients to the solution. Monitoring ions in solution is interesting, but it is not the key to effective maintenance.

Bugbee, Bruce

2004-01-01

377

Recirculation bubbler for glass melter apparatus  

DOEpatents

A gas bubbler device provides enhanced recirculation of molten glass within a glass melter apparatus. The bubbler device includes a tube member disposed within a pool of molten glass contained in the melter. The tube member includes a lower opening through which the molten glass enters and upper slots disposed close to (above or below) the upper surface of the pool of molten glass and from which the glass exits. A gas (air) line is disposed within the tube member and extends longitudinally thereof. A gas bubble distribution device, which is located adjacent to the lower end of the tube member and is connected to the lower end of the gas line, releases gas through openings therein so as to produce gas bubbles of a desired size in the molten glass and in a distributed pattern across the tube member.

Guerrero, Hector (Evans, GA); Bickford, Dennis (Folly Beach, SC)

2007-06-05

378

Biofilm accumulation in drinking water distribution systems  

Microsoft Academic Search

In order to classify the relative importance of the parameters governing the accumulation of biofilm in drinking water distribution systems, a study has been carried out, using an industrial pilot plant fed with finished waters, with three main objectives, viz. (i) determination of biofilm density on pipe surfaces (PVC or cement lined cast iron) as a function of the distance

J. C. Block; K. Haudidier; J. L. Paquin; J. Miazga; Y. Levi

1993-01-01

379

Privatization of Water Systems in France  

Microsoft Academic Search

Private companies in France, operating under the oversight of local municipal authorities, are responsible for a large share of the country's water and sewer utilities. Highly successful in providing state-of-the-art technologies for the management and treatment of water and wastewater systems, these firms now have the financial and human resources to extend their operations abroad, thus providing leadership in the

Jean-Dominique Deschamps

1986-01-01

380

Solar thermal water pumping systems: a review  

Microsoft Academic Search

A number of attempts have been made by scientists to utilize solar energy for irrigation water pumping. It is mainly a problem of conversion of heat energy available from the sun, to mechanical energy. Some ingenious methods have been devised to utilize the available energy at low temperatures. This paper reviews past efforts to develop solar thermal water pumping systems

Y. W. Wong; K. Sumathy

1999-01-01

381

Captive Water Current Power System  

SciTech Connect

Current energy is converted into shaft power in two stages; First, buoyant power units with stationary hydrofoil wings reach faster than the current speed by sweeping out a captive path. Second, turbines at said power units convert the fast relative local current into shaft power. Power units sweeping along the water surface, using cycloidal turbine methods, as well as power units sweeping on a submerged path, using axial flow turbine methods, are described.

Wuenscher, H. F.; Wuenscher, H. A.

1984-01-31

382

INTEGRATED WATER TREATMENT SYSTEM PERFORMANCE EVALUATION  

SciTech Connect

This document describes the results of an evaluation of the current Integrated Water Treatment System (IWTS) operation against design performance and a determination of short term and long term actions recommended to sustain IWTS performance.

SEXTON RA; MEEUWSEN WE

2009-03-12

383

Resources for Small Water Systems in Texas  

E-print Network

Texas (Alice) and the High Plains (Levelland) provide on- site training and technical assistance. ORCA staff at these fi eld offi ces can help communi- ties develop loan and grant applications for water and wastewater systems. The Texas Engineering...

Dozier, Monty; Theodori, Gene L.; Jensen, Ricard

2007-03-28

384

Rate Setting for Small Water Systems  

E-print Network

-funded center at Boise State University has developed a free software program (?RATE Checkup?) that helps small water systems set rates and prepare budget forecasts. The center that serves Texas is locat- ed at New Mexico Tech University. In addition...

Dozier, Monty; Theodori, Gene L.; Jensen, Ricard

2007-03-28

385

Advanced Atmospheric Water Vapor DIAL Detection System  

NASA Technical Reports Server (NTRS)

Measurement of atmospheric water vapor is very important for understanding the Earth's climate and water cycle. The remote sensing Differential Absorption Lidar (DIAL) technique is a powerful method to perform such measurement from aircraft and space. This thesis describes a new advanced detection system, which incorporates major improvements regarding sensitivity and size. These improvements include a low noise advanced avalanche photodiode detector, a custom analog circuit, a 14-bit digitizer, a microcontroller for on board averaging and finally a fast computer interface. This thesis describes the design and validation of this new water vapor DIAL detection system which was integrated onto a small Printed Circuit Board (PCB) with minimal weight and power consumption. Comparing its measurements to an existing DIAL system for aerosol and water vapor profiling validated the detection system.

Refaat, Tamer F.; Elsayed-Ali, Hani E.; DeYoung, Russell J. (Technical Monitor)

2000-01-01

386

Prototype solar heating and hot water systems  

NASA Technical Reports Server (NTRS)

Progress made in the development of a solar hot water and space heating system is described in four quarterly reports. The program schedules, technical status and other program activities from 6 October 1976 through 30 September 1977 are provided.

1978-01-01

387

WATER QUALITY EARLY WARNING SYSTEMS FOR SOURCE WATER AND DISTRIBUTION SYSTEM MONITORING  

EPA Science Inventory

A variety of probes for use in continuous monitoring of water quality exist. They range from single parameter chemical/physical probes to comprehensive screening systems based on whole organism responses. Originally developed for monitoring specific characteristics of water qua...

388

Water system microbial check valve development  

NASA Technical Reports Server (NTRS)

A residual iodine microbial check valve (RIMCV) assembly was developed and tested. The assembly is designed to be used in the space shuttle potable water system. The RIMCV is based on an anion exchange resin that is supersaturated with an iodine solution. This system causes a residual to be present in the effluent water which provides continuing bactericidal action. A flight prototype design was finalized and five units were manufactured and delivered.

Colombo, G. V.; Greenley, D. R.; Putnam, D. F.

1978-01-01

389

Traffic and proliferative responses of recirculating lymphocytes in fetal calves.  

PubMed Central

The thoracic duct or efferent prescapular duct was cannulated in four fetal calves aged 121-259 days post-conception. The duration of lymph flow ranged from 2 to 20 days and the mean flow rates sustained over these collection periods varied from 5.4 to 48.8 ml/hr. Lymphocyte output ranged from 4.4 x 10(6) cells/hr in thoracic duct lymph from a 121-day fetus to 3.9 x 10(8) cells/hr in efferent prescapular lymph from a 259-day fetus. The circulating lymphocyte pool in fetal calves of about 120 and 190 days gestational age was calculated to contain, respectively, 4 x 10(8) cells and 2 x 10(10) cells. The proportion of lymphocytes bearing surface immunoglobulin detected in fetal lymph ranged from 2.1% to 8.7%. Recirculating lymphocytes from fetal calves produced strong proliferative responses when stimulated by T-cell mitogens but responded poorly to B-cell mitogens. Fetal lymphocytes also responded to stimulation by allogeneic cells and stimulated other cells to proliferate during mixed lymphocyte culture. When stimulated with Con A, fetal lymphocytes secreted IL-2 to a degree that was indistinguishable from the secretory behaviour of lymphocytes from adult animals. The results presented in this paper show that chronic lymphatic fistulae can be established successfully in fetal calves to give access to recirculating lymphocytes. This provides a new experimental approach for studying the development of the bovine immune system. PMID:2971606

Hein, W R; Shelton, J N; Simpson-Morgan, M W; Morris, B

1988-01-01

390

Space Station Freedom regenerative water recovery system configuration selection  

NASA Technical Reports Server (NTRS)

The Space Station Freedom (SSF) must recover water from various waste water sources to reduce 90 day water resupply demands for a four/eight person crew. The water recovery system options considered are summarized together with system configuration merits and demerits, resource advantages and disadvantages, and water quality considerations used to select the SSF water recovery system.

Reysa, R.; Edwards, J.

1991-01-01

391

Decision support system for drinking water management  

NASA Astrophysics Data System (ADS)

The problems in drinking water management are complex and often solutions must be reached under strict time constrains. This is especially distinct in case of environmental accidents in the catchment areas of the wells that are used for drinking water supply. The beneficial tools that can help decision makers and make program of activities more efficient are decision support systems (DSS). In general they are defined as computer-based support systems that help decision makers utilize data and models to solve unstructured problems. The presented DSS was developed in the frame of INCOME project which is focused on the long-term stable and safe drinking water supply in Ljubljana. The two main water resources Ljubljana polje and Barje alluvial aquifers are characterized by a strong interconnection of surface and groundwater, high vulnerability, high velocities of groundwater flow and pollutant transport. In case of sudden pollution, reactions should be very fast to avoid serious impact to the water supply. In the area high pressures arising from urbanization, industry, traffic, agriculture and old environmental burdens. The aim of the developed DSS is to optimize the activities in cases of emergency water management and to optimize the administrative work regarding the activities that can improve groundwater quality status. The DSS is an interactive computer system that utilizes data base, hydrological modelling, and experts' and stakeholders' knowledge. It consists of three components, tackling the different abovementioned issues in water management. The first one utilizes the work on identification, cleaning up and restoration of illegal dumpsites that are a serious threat to the qualitative status of groundwater. The other two components utilize the predictive capability of the hydrological model and scenario analysis. The user interacts with the system by a graphical interface that guides the user step-by-step to the recommended remedial measures. Consequently, the acquisition of information to support the water management's decisions is simplified and faster, thus contributing to more efficient water management and a safer supply of drinking water.

Janža, M.

2012-04-01

392

Investigation of groundwater recirculation for the removal of RDX from the Pantex Plant perched aquifer  

SciTech Connect

The Pantex Plant near Amarillo, Texas, is a US Department of Energy (DOE) facility that has been in operation since 1942. Past and present operations at Pantex include the creation of chemical high explosives components for nuclear weapons and assembly and disassembly of nuclear weapons. The Pantex Plant is underlain by the Ogallala aquifer, which in this area, consists of the main water-bearing unit and a perched water zone. These are separated by a fine-grained zone of low permeability. Multiple contaminant plumes containing high explosive (HE) compounds have been detected in the perched aquifer beneath the plant. The occurrence of these contaminants is the result of past waste disposal practices at the facility. RDX is an HE compound, which has been detected in the groundwater of the perched aquifer at significant concentrations. A pilot-scale, dual-phase extraction treatment system has been installed at one location at the plant, east of Zone 12, to test the effectiveness of such a system on the removal of these contaminants from the subsurface. A tracer test using a conservative tracer, bromide (Br), was conducted at the treatment site in 1996. In addition to the bromide, RDX and water elevations in the aquifer were monitored. Using data from the tracer test and other relevant data from the investigations at Pantex, flow and contaminant transport in the perched aquifer were simulated with groundwater models. The flow was modeled using MODFLOW and the transport of contaminants in the aqueous phase was modeled using MT3D. Modeling the perched aquifer had been conducted to characterize the flow in the perched aquifer; estimate RDX retardation in the perched aquifer; and evaluate the use of groundwater re-circulation to enhance the extraction of RDX from the perched aquifer.

Woods, A.L. [ed.; Barnes, D.L. [Amarillo National Resource Center for Plutonium, TX (United States); Boles, K.M.; Charbeneau, R.J. [Univ. of Texas, Austin, TX (United States); Black, S.; Rainwater, K. [Texas Tech Univ., Lubbock, TX (United States). Water Resources Center

1998-07-01

393

Effect of sparger design on hydrodynamics of a gas recirculation anaerobic bioreactor.  

PubMed

The effects of sparger design and gas flow rate on, gas holdup distribution and liquid (slurry) recirculation velocity have been studied in a surrogate anaerobic bioreactor used for treating bovine waste with a conical bottom mixed by gas recirculation. A single orifice sparger (SOS) and a multi-orifice ring sparger (MORS) with the same orifice open area and gas flow rates (hence the same process power input) are compared in this study. The advanced non-invasive techniques of computer automated tomography (CT) and computer automated radioactive particle tracking (CARPT) were employed to determine gas holdup, liquid recirculation velocity, and the poorly mixed zones. Gas flows (Q(g)) ranging of 0.017 x 10(-3) m(3)/s to 0.083 x 10(-3) m(3)/s were used which correspond to draft tube superficial gas velocities ranging from 1.46 x 10(-2) m/s to 7.35 x 10(-2) m/s (based on draft tube diameter). Air was used for the gas, as the molecular weights of air and biogas (consisting mainly of CH(4) and CO(2)) are in the same range (biogas: 28.32-26.08 kg/kmol and air: 28.58 kg/kmol). When compared to the SOS for a given gas flow rate, the MORS gave better gas holdup distribution in the draft tube, enhanced the liquid (slurry) recirculation, and reduced the fraction of the poorly mixed zones. The improved gas holdup distribution in the draft tube was found to have increased the overall liquid velocity. Hence, for the same process power input the MORS system performed better by enhancing the liquid recirculation and reducing the poorly mixed zones. PMID:17514754

Varma, Rajneesh; Al-Dahhan, Muthanna

2007-12-15

394

Hydro static water level systems at Fermilab  

SciTech Connect

Several Hydrostatic Water Leveling systems (HLS) are in use at Fermilab. Three systems are used to monitor quadrupoles in the Tevatron and two systems are used to monitor ground motion for potential sites for the International Linear Collider (ILC). All systems use capacitive sensors to determine the water level of water in a pool. These pools are connected with tubing so that relative vertical shifts between sensors can be determined. There are low beta quadrupoles at the B0 and D0 interaction regions of Tevatron accelerator. These quadrupoles use BINP designed and built sensors and have a resolution of 1 micron. All regular lattice superconducting quadrupoles (a total of 204) in the Tevatron use a Fermilab designed system and have a resolution of 6 microns. Data on quadrupole motion due to quenches, changes in temperature will be presented. In addition data for ground motion for ILC studies caused by natural and cultural factors will be presented.

Volk, J.T.; Guerra, J.A.; Hansen, S.U.; Kiper, T.E.; Jostlein, H.; Shiltsev, V.; Chupyra, A.; Kondaurov, M.; Singatulin, S.

2006-09-01

395

21 CFR 876.5665 - Water purification system for hemodialysis.  

... Water purification system for hemodialysis. 876.5665 Section 876... Water purification system for hemodialysis. (a) Identification. A water purification system for hemodialysis is a device that is intended...

2014-04-01

396

21 CFR 876.5665 - Water purification system for hemodialysis.  

Code of Federal Regulations, 2013 CFR

... Water purification system for hemodialysis. 876.5665 Section 876... Water purification system for hemodialysis. (a) Identification. A water purification system for hemodialysis is a device that is intended...

2013-04-01

397

21 CFR 876.5665 - Water purification system for hemodialysis.  

Code of Federal Regulations, 2011 CFR

... Water purification system for hemodialysis. 876.5665 Section 876... Water purification system for hemodialysis. (a) Identification. A water purification system for hemodialysis is a device that is intended...

2011-04-01

398

21 CFR 876.5665 - Water purification system for hemodialysis.  

Code of Federal Regulations, 2012 CFR

... Water purification system for hemodialysis. 876.5665 Section 876... Water purification system for hemodialysis. (a) Identification. A water purification system for hemodialysis is a device that is intended...

2012-04-01

399

21 CFR 876.5665 - Water purification system for hemodialysis.  

Code of Federal Regulations, 2010 CFR

... Water purification system for hemodialysis. 876.5665 Section 876... Water purification system for hemodialysis. (a) Identification. A water purification system for hemodialysis is a device that is intended...

2010-04-01

400

30 CFR 75.1101-6 - Water sprinkler systems; general.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Water sprinkler systems; general. 75...Fire Protection § 75.1101-6 Water sprinkler systems; general. Water sprinkler systems may be installed to protect main and secondary belt-conveyor...

2011-07-01

401

30 CFR 75.1101-6 - Water sprinkler systems; general.  

...2014-07-01 2014-07-01 false Water sprinkler systems; general. 75...Fire Protection § 75.1101-6 Water sprinkler systems; general. Water sprinkler systems may be installed to protect main and secondary belt-conveyor...

2014-07-01

402

30 CFR 75.1101-6 - Water sprinkler systems; general.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Water sprinkler systems; general. 75...Fire Protection § 75.1101-6 Water sprinkler systems; general. Water sprinkler systems may be installed to protect main and secondary belt-conveyor...

2010-07-01

403

30 CFR 75.1101-6 - Water sprinkler systems; general.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Water sprinkler systems; general. 75...Fire Protection § 75.1101-6 Water sprinkler systems; general. Water sprinkler systems may be installed to protect main and secondary belt-conveyor...

2012-07-01

404

30 CFR 75.1101-6 - Water sprinkler systems; general.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Water sprinkler systems; general. 75...Fire Protection § 75.1101-6 Water sprinkler systems; general. Water sprinkler systems may be installed to protect main and secondary belt-conveyor...

2013-07-01

405

21 CFR 1240.86 - Protection of pier water system.  

Code of Federal Regulations, 2011 CFR

... 2011-04-01 false Protection of pier water system. 1240.86 Section 1240...Potable Water § 1240.86 Protection of pier water system. No vessel engaged in...between its nonpotable water system and any pier potable water system unless...

2011-04-01

406

21 CFR 1240.86 - Protection of pier water system.  

Code of Federal Regulations, 2010 CFR

... 2010-04-01 false Protection of pier water system. 1240.86 Section 1240...Potable Water § 1240.86 Protection of pier water system. No vessel engaged in...between its nonpotable water system and any pier potable water system unless...

2010-04-01

407

Engineering aspects of water pollution control systems  

Microsoft Academic Search

The importance of proper engineering when providing pollution control systems is emphasized. Organization of engineering projects is described in detail. Included are discussions of: (1) collection and evaluation of available data; (2) establishment of survey and test program; (3) integration and evaluation of findings; (4) establishment of pollution control and water utilization systems; and (5) specification and detailed design preparation.

R. G. Dalbke; A. J. Turk

1967-01-01

408

ADA's Virtual Node based Water System Simulator  

Microsoft Academic Search

This paper presents the application of Virtual Nodes for the distributed implementation of the nonlinear network tearing algorithm. The program is implemented on a network of SUN\\/SPARC workstations connected by an Ethernet communication link, having a UNIX operating system. However, the gradual growth of the water system resulted in the accumulation of the increasing volume of data which had to

A. Hosseinzaman; A. Bargiela

409

Distilled Water Distribution Systems. Laboratory Design Notes.  

ERIC Educational Resources Information Center

Factors concerning water distribution systems, including an evaluation of materials and a recommendation of materials best suited for service in typical facilities are discussed. Several installations are discussed in an effort to bring out typical features in selected applications. The following system types are included--(1) industrial…

Sell, J.C.

410

Adapting water accounting for integrated water resource management. The Júcar Water Resource System (Spain)  

NASA Astrophysics Data System (ADS)

An increase in water demands, exacerbated by climate change and the tightening of environmental requirements, leads to a reduction in available water resources for economic uses. This situation poses challenges for water resource planning and management. Water accounting has emerged as an appropriate tool to improve transparency and control in water management. There are multiple water accounting approaches, but they generally involve a very exhaustive list of accounted concepts. According to our findings in this research, one of the best water accounting methodologies is the Australian Water Accounting Standard. However, its implementation for integrated water resource planning and management purposes calls into questioning the amount of information and level of detail necessary for the users of water accounts. In this paper, we present a different method of applying the Australian Water Accounting Standard in relation to water resource management, which improves its utility. In order to compare the original approach and that proposed here, we present and discuss an application to the Júcar Water Resource System, in eastern Spain.

Momblanch, Andrea; Andreu, Joaquín; Paredes-Arquiola, Javier; Solera, Abel; Pedro-Monzonís, María

2014-11-01

411

In-situ continuous water monitoring system  

DOEpatents

An in-situ continuous liquid monitoring system for continuously analyzing volatile components contained in a water source comprises: a carrier gas supply, an extraction container and a mass spectrometer. The carrier gas supply continuously supplies the carrier gas to the extraction container and is mixed with a water sample that is continuously drawn into the extraction container by the flow of carrier gas into the liquid directing device. The carrier gas continuously extracts the volatile components out of the water sample. The water sample is returned to the water source after the volatile components are extracted from it. The extracted volatile components and the carrier gas are delivered continuously to the mass spectrometer and the volatile components are continuously analyzed by the mass spectrometer.

Thompson, Cyril V. (Knoxville, TN); Wise, Marcus B. (Kingston, TN)

1998-01-01

412

In-situ continuous water monitoring system  

DOEpatents

An in-situ continuous liquid monitoring system for continuously analyzing volatile components contained in a water source comprises: a carrier gas supply, an extraction container and a mass spectrometer. The carrier gas supply continuously supplies the carrier gas to the extraction container and is mixed with a water sample that is continuously drawn into the extraction container by the flow of carrier gas into the liquid directing device. The carrier gas continuously extracts the volatile components out of the water sample. The water sample is returned to the water source after the volatile components are extracted from it. The extracted volatile components and the carrier gas are delivered continuously to the mass spectrometer and the volatile components are continuously analyzed by the mass spectrometer. 2 figs.

Thompson, C.V.; Wise, M.B.

1998-03-31

413

Alternative Electrochemical Systems for Ozonation of Water  

NASA Technical Reports Server (NTRS)

Electrochemical systems that are especially well suited for the small-scale generation of ozone and ozonated water for local use have been invented. These systems can operate with very little maintenance, and the only inputs needed during operation are electric power and water. Ozonated water produced by these systems can be used in diverse industrial applications: A few examples include sterilization in the brewing industry, general disinfection, and treatment of sewage and recycled water. The basic principle of operation admits of several alternative system configurations. The heart of the system is a stack of electrolytic cells, each containing a proton-exchange membrane (which serves as a solid electrolyte) sandwiched between a catalytic anode and a catalytic cathode. Preferably, the proton-exchange membrane is made of a perfluorinated sulfonic acid polymer. During electrolysis, a mixture of O2 and O3 gases is generated at the anode and H2 is generated at the cathode. Some of the O3 generated at the anode becomes dissolved in the water. The proportion of O3 in the O2/O3 mixture can be maximized by the selection of suitable electrode materials and the use of a high overpotential. Although the proton-exchange membrane conducts protons, it does not conduct electrons. It is also impermeable by gases; consequently, it maintains separation between the O2/O3 mixture evolved at the anode and the H2 evolved at the cathode.

Andrews, Craig C.; Murphy, Oliver J.

2003-01-01

414

High temperature hot water distribution system study  

SciTech Connect

The existing High Temperature Hot Water (HTHW) Distribution System has been plagued with design and construction deficiencies since startup of the HTHW system, in October 1988. In October 1989, after one year of service, these deficiencies were outlined in a technical evaluation. The deficiencies included flooded manholes, sump pumps not hooked up, leaking valves, contaminated HTHW water, and no cathodic protection system. This feasibility study of the High Temperature Hot Water (HTHW) Distribution System was performed under Contract No. DACA0l-94-D-0033, Delivery Order 0013, Modification 1, issued to EMC Engineers, Inc. (EMC), by the Norfolk District Corps of Engineers, on 25 April 1996. The purpose of this study was to determine the existing conditions of the High Temperature Hot Water Distribution System, manholes, and areas of containment system degradation. The study focused on two areas of concern, as follows: * Determine existing conditions and areas of containment system degradation (leaks) in the underground carrier pipes and protective conduit. * Document the condition of underground steel and concrete manholes. To document the leaks, a site survey was performed, using state-of-the-art infrared leak detection equipment and tracer gas leak detection equipment. To document the condition of the manholes, color photographs were taken of the insides of 125 manholes, and notes were made on the condition of these manholes.

NONE

1996-12-01

415

Energy optimization of water distribution system  

SciTech Connect

In order to analyze pump operating scenarios for the system with the computer model, information on existing pumping equipment and the distribution system was collected. The information includes the following: component description and design criteria for line booster stations, booster stations with reservoirs, and high lift pumps at the water treatment plants; daily operations data for 1988; annual reports from fiscal year 1987/1988 to fiscal year 1991/1992; and a 1985 calibrated KYPIPE computer model of DWSD`s water distribution system which included input data for the maximum hour and average day demands on the system for that year. This information has been used to produce the inventory database of the system and will be used to develop the computer program to analyze the system.

Not Available

1993-02-01

416

Water injected fuel cell system compressor  

DOEpatents

A fuel cell system including a dry compressor for pressurizing air supplied to the cathode side of the fuel cell. An injector sprays a controlled amount of water on to the compressor's rotor(s) to improve the energy efficiency of the compressor. The amount of water sprayed out the rotor(s) is controlled relative to the mass flow rate of air inputted to the compressor.

Siepierski, James S. (Williamsville, NY); Moore, Barbara S. (Victor, NY); Hoch, Martin Monroe (Webster, NY)

2001-01-01

417

Water Resources Data System State Climate Office  

NSDL National Science Digital Library

The Water Resources Data System is a "clearinghouse of hydrological and climatological data for the State of Wyoming" provided by the University of Wyoming. Online data include a water quality database, climatological data (such as snow depth and precipitation), and earthquake and landslide data. A water library link contains research briefs, publications, a reference shelf, newsletters, and other related documents. Additional links on the main page include US Geological Survey stream flow conditions, the state climatologist office, data clearinghouses, and other Wyoming-specific informational sites.

418

GIS-BASED WATER BALANCE SYSTEM FOR INTEGRATED SUSTAINABILITY MANAGEMENT OF WATER DISTRIBUTION ASSETS  

Microsoft Academic Search

Water loss from water distribution systems is a major concern to water utilities. Water utilities around the world are becoming more focused on adopting a proactive approach to managing water loss. The amount of lost water can be significant, reaching levels as high as 50% of production. However, water loss management is still not widely practiced by utilities in North

Delta Regina Hotel; Saskatchewan Regina; Mahmoud R. Halfawy; Osama Hunaidi

419

STATE OF CALIFORNIA AIR, WATER SIDE SYSTEM, SERVICE HOT WATER & POOL REQUIREMENTS  

E-print Network

STATE OF CALIFORNIA AIR, WATER SIDE SYSTEM, SERVICE HOT WATER & POOL REQUIREMENTS CEC-MECH-2C exception(s) to §144(g) apply. #12;STATE OF CALIFORNIA AIR, WATER SIDE SYSTEM, SERVICE HOT WATER & POOL REQUIREMENTS CEC-MECH-2C (Revised 08/09) CALIFORNIA ENERGY COMMISSION WATER SIDE SYSTEM REQUIREMENTS (Part 2

420

Evaluation of a cost effective technique for treating aquaculture water discharge using Lolium perenne Lam as a biofilter  

Microsoft Academic Search

Wastewater stabilization ponds generate low cost by-products that are useful for agriculture. The utilization of these by-products for soil amendment and as a source of nutrients for plants requires a high level of sanitation and stabilization of the organic matter, to maintain acceptable levels of soil, water and air quality. In this study, two aquaculture wastewater treatment systems; recirculating system

André NDUWIMANA; Xiang-long YANG; Li-ren WANG

2007-01-01

421

Impact of nitrate-enhanced leachate recirculation on gaseous releases from a landfill bioreactor cell  

SciTech Connect

This study evaluates the impact of nitrate injection on a full scale landfill bioreactor through the monitoring of gaseous releases and particularly N{sub 2}O emissions. During several weeks, we monitored gas concentrations in the landfill gas collection system as well as surface gas releases with a series of seven static chambers. These devices were directly connected to a gas chromatograph coupled to a flame ionisation detector and an electron capture detector (GC-FID/ECD) placed directly on the field. Measurements were performed before, during and after recirculation of raw leachate and nitrate-enhanced leachate. Raw leachate recirculation did not have a significant effect on the biogas concentrations (CO{sub 2}, CH{sub 4} and N{sub 2}O) in the gas extraction network. However, nitrate-enhanced leachate recirculation induced a marked increase of the N{sub 2}O concentrations in the gas collected from the recirculation trench (100-fold increase from 0.2 ppm to 23 ppm). In the common gas collection system however, this N{sub 2}O increase was no more detectable because of dilution by gas coming from other cells or ambient air intrusion. Surface releases through the temporary cover were characterized by a large spatial and temporal variability. One automated chamber gave limited standard errors over each experimental period for N{sub 2}O releases: 8.1 {+-} 0.16 mg m{sup -2} d{sup -1} (n = 384), 4.2 {+-} 0.14 mg m{sup -2} d{sup -1} (n = 132) and 1.9 {+-} 0.10 mg m{sup -2} d{sup -1} (n = 49), during, after raw leachate and nitrate-enhanced leachate recirculation, respectively. No clear correlation between N{sub 2}O gaseous surface releases and recirculation events were evidenced. Estimated N{sub 2}O fluxes remained in the lower range of what is reported in the literature for landfill covers, even after nitrate injection.

Tallec, G.; Bureau, C. [Cemagref, UR HBAN, Parc de Tourvoie, BP44, F-92163 Antony (France); Peu, P.; Benoist, J.C. [Cemagref, UR GERE, 17 Avenue de Cucille, CS 64427, F-35044 Rennes (France); Lemunier, M. [Suez-Environnement, CIRADE, 38 Av. Jean Jaures, 78440 Gargenville (France); Budka, A.; Presse, D. [SITA France, 132 Rue des 3 Fontanot, 92000 Nanterre Cedex (France); Bouchez, T. [Cemagref, UR HBAN, Parc de Tourvoie, BP44, F-92163 Antony (France)], E-mail: theodore.bouchez@cemagref.fr

2009-07-15

422

Loop-synchronous polarization scrambling technique for simulating polarization effects using recirculating fiber loops  

Microsoft Academic Search

A loop-synchronous polarization-scrambling technique has been proposed for the purpose of simulating polarization effects in straight-line systems using recirculating loops. This technique uses a fast polarization controller within a fiber loop. The polarization controller changes its transmission matrix after each round trip of the optical signal circulating through the loop; thus, the periodic polarization transform of the loop is avoided.

Q. Yu; L.-S. Yan; S. Lee; Y. Xie; A. E. Willner

2003-01-01

423

Heat and mass transfer in turbulent flows with several recirculated flow eddies  

Microsoft Academic Search

Numerical modeling of the concentration and temperature distribution in axial symmetrical systems with several recirculated flow eddies, which is based on various 2D stationary k-? models and commercial codes, e.g. ANSYS and FLUENT, leads to results, which are significantly different from experimental data. Therefore additional user-defined subroutines were included in the commercial program code to improve the turbulent heat and

E. Baake; B. Nacke; A. Jakovics; A. Umbrashko

2001-01-01

424

Biodeterioration of materials in water reclamation systems  

NASA Technical Reports Server (NTRS)

The chemicals produced by the microbial processes involved in the 'biofilms' which form on the surfaces of manned spacecraft water reclamation systems encompass both metals and organic poisons; both are potential hazards to astronaut health and the growth of the plants envisioned for closed-cycle life support systems. Image analysis is here shown to be a very useful technique for the study of biofilm formation on candidate water-processor materials for Space Station Freedom. The biodeterioration of materials exposed to biofilms can be swiftly evaluated by means of electrochemical impedance spectroscopy.

Ford, Tim; Maki, James S.; Mitchell, Ralph

1992-01-01

425

40 CFR 258.51 - Ground-water monitoring systems.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2011-07-01 true Ground-water monitoring systems. 258.51 Section...MUNICIPAL SOLID WASTE LANDFILLS Ground-Water Monitoring and Corrective Action § 258.51 Ground-water monitoring systems. (a) A...

2012-07-01

426

40 CFR 258.51 - Ground-water monitoring systems.  

...2014-07-01 2014-07-01 false Ground-water monitoring systems. 258.51 Section...MUNICIPAL SOLID WASTE LANDFILLS Ground-Water Monitoring and Corrective Action § 258.51 Ground-water monitoring systems. (a) A...

2014-07-01

427

40 CFR 258.51 - Ground-water monitoring systems.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Ground-water monitoring systems. 258.51 Section...MUNICIPAL SOLID WASTE LANDFILLS Ground-Water Monitoring and Corrective Action § 258.51 Ground-water monitoring systems. (a) A...

2011-07-01

428

40 CFR 258.51 - Ground-water monitoring systems.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Ground-water monitoring systems. 258.51 Section...MUNICIPAL SOLID WASTE LANDFILLS Ground-Water Monitoring and Corrective Action § 258.51 Ground-water monitoring systems. (a) A...

2013-07-01

429

40 CFR 258.51 - Ground-water monitoring systems.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Ground-water monitoring systems. 258.51 Section...MUNICIPAL SOLID WASTE LANDFILLS Ground-Water Monitoring and Corrective Action § 258.51 Ground-water monitoring systems. (a) A...

2010-07-01

430

Distribution of Off-Flavor Compounds and Isolation of Geosmin-Producing Bacteria in a Series of Water Recirculating Systems for Rainbow Trout Culture  

Technology Transfer Automated Retrieval System (TEKTRAN)

Pre-harvest “off-flavor” in aquaculture products results in large economic losses to producers due to delayed harvest. The common off-flavors “earthy” and “musty” are due to the presence of geosmin and 2-methylisoborneol (MIB), respectively. Although certain species of cyanobacteria are responsibl...

431

The effects of ozonation on performance, health and welfare of rainbow trout Oncorhynchus mykiss in low-exchange water recirculation aquaculture systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

A controlled four-month trial was conducted to compare the effects of ozonation (oxidation-reduction potential setpoint = 250 mV) versus no ozonation on rainbow trout Oncorhynchus mykiss performance, health, and welfare in replicated WRAS operated at low exchange rates (0.26% of the total recirculat...

432

Interfacial Properties of Polydimethylsiloxane-Water Systems  

NASA Astrophysics Data System (ADS)

Polydimethylsiloxane (PDMS) is a main constituent of silicone adhesives, which have a wide use as adhesives. Often these adhesives are used as sealants. The interaction between water and PDMS is of fundamental importance. To improve our understanding at the molecular level, we have performed molecular dynamics (MD) simulations of PDMS in the presence of water, with the long-term goal of studying how water molecules effect debonding at the surface. Knowledge of the basic interfacial properties of a multicomponent system, such as the surface tension, contact angle, and diffusion constant, are essential to obtain the proper dynamic behavior in a molecular simulation of adhesion and wetting processes. Explicit-atom simulations of 10^5 or more atoms were used to determine liquid-vapor surface tension and the contact angle for water on the surface of PDMS. We present results for the dependence of the surface tension on chain length and end-group functionality.

Ismail, Ahmed E.; Grest, Gary S.; Stevens, Mark J.; Tsige, Mesfin; Heine, David R.

2008-03-01

433

Wash water waste pretreatment system study  

NASA Technical Reports Server (NTRS)

The use of real wash water had no adverse effect on soap removal when an Olive Leaf soap based system was used; 96 percent of the soap was removed using ferric chloride. Numerous chemical agents were evaluated as antifoams for synthetic wash water. Wash water surfactants used included Olive Leaf Soap, Ivory Soap, Neutrogena and Neutrogena Rain Bath Gel, Alipal CO-436, Aerosol 18, Miranol JEM, Palmeto, and Aerosol MA-80. For each type of soapy wash water evaluated, at least one antifoam capable of causing nonpersistent foam was identified. In general, the silicones and the heavy metal ions (i.e., ferric, aluminum, etc.) were the most effective antifoams. Required dosage was in the range of 50 to 200 ppm.

1976-01-01

434

Wheat response to differences in water and nutritional status between zeoponic and hydroponic growth systems  

NASA Technical Reports Server (NTRS)

Hydroponic culture has traditionally been used for controlled environment life support systems (CELSS) because the optimal environment for roots supports high growth rates. Recent developments in zeoponic substrate and microporous tube irrigation (ZPT) also offer high control of the root environment. This study compared the effect of differences in water and nutrient status of ZPT or hydroponic culture on growth and yield of wheat (Triticum aestivum L. cv. USU-Apogee). In a side-by-side test in a controlled environment, wheat was grown in ZPT and recirculating hydroponics to maturity. Water use by plants grown in both culture systems peaked at 15 to 20 L m-2 d-1 up to Day 40, after which it declined more rapidly for plants grown in ZPT culture due to earlier senescence of leaves. No consistent differences in water status were noted between plants grown in the two culture systems. Although yield was similar, harvest index was 28% lower for plants grown in ZPT than in hydroponic culture. Sterile green tillers made up 12 and 0% of the biomass of plants grown in ZPT and hydroponic culture, respectively. Differences in biomass partitioning were attributed primarily to NH4-N nutrition of plants grown in ZPT compared with NO3-N in hydroponic nutrient solution. It is probable that NH4-N-induced Ca deficiency produced excess tillering and lower harvest index for plants grown in ZPT culture. These results suggest that further refinements in zeoponic substrate would make ZPT culture a viable alternative for achieving high productivity in a CELSS.

Steinberg, S. L.; Ming, D. W.; Henderson, K. E.; Carrier, C.; Gruener, J. E.; Barta, D. J.; Henninger, D. L.

2000-01-01

435

Emerging problems with zoonotic bacteria in intensive warm water fish culture: facts and risks  

Technology Transfer Automated Retrieval System (TEKTRAN)

With the development of warm water aquaculture in intensive indoor recirculation systems in Europe and the United States new bacterial disease problems occur, especially in the cultured fish, and in humans. These so called zoonotic bacteria are more frequently isolated from severe disease outbreaks...

436

UREA/ammonium ion removal system for the orbiting frog otolith experiment. [ion exchange resins for water treatment during space missions  

NASA Technical Reports Server (NTRS)

The feasibility of using free urease enzyme and ANGC-101 ion exchange resin to remove urea and ammonium ion for space system waste water applications was studied. Specifically examined is the prevention of urea and ammonia toxicity in a 30-day Orbiting Frog Otolith (OFO) flight experiment. It is shown that free urease enzyme used in conjunction with ANGC-101 ion-exchange resin and pH control can control urea and amonium ion concentration in unbuffered recirculating water. In addition, the resin does not adversely effect the bullfrogs by lowering the concentration of cations below critical minimum levels. Further investigations on bioburden control, frog waste excretion on an OFO diet, a trade-off analysis of methods of automating the urea/ammonium ion removal system and fabrication and test of a semiautomated breadboard were recommended as continuing efforts. Photographs of test equipment and test animals are shown.

Schulz, J. R.; Anselmi, R. T.

1976-01-01

437

Water electrolysis system refurbishment and testing  

NASA Technical Reports Server (NTRS)

The electrolytic oxygen generator for the back-up water electrolysis system in a 90-day manned test was refurbished, improved and subjected to a 182-day bench test. The performance of the system during the test demonstrated the soundness of the basic electrolysis concept, the high development status of the automatic controls which allowed completely hands-off operation, and the capability for orbital operation. Some design improvements are indicated.

Greenough, B. M.

1972-01-01

438

Simultaneous Water Filling in Mutually Interfering Systems  

Microsoft Academic Search

In this paper we investigate properties of simultaneous water filling for a wireless system with two mutually interfering transmitters and receivers with non- cooperative coding strategies. This is slightly different from the traditional interference channel probl em which assumes that transmitters cooperate in their respective coding strategies, and that interference cancellation can be performed at the receivers. In this non-cooperative

Otilia Popescu; Dimitrie C. Popescu; Christopher Rose

2007-01-01

439

Prototype solar heating and hot water system  

NASA Technical Reports Server (NTRS)

Progress is reported in the development of a solar heating and hot water system which uses a pyramidal optics solar concentrator for heating, and consists of the following subsystems: collector, control, transport, and site data acquisition. Improvements made in the components and subsystems are discussed.

1977-01-01

440

LIGHTWEIGHT GREEN ROOF WATER RETENTION SYSTEM  

EPA Science Inventory

During Phase I, we have forged numerous necessary partnerships, which will allow us to begin our implementation tests. Working with the Philadelphia Water Department (PWD) and Drexel Smart House (DSH) we have 3 to 4 prime test sites for our system. We plan to execute our insta...

441

CONSTANT VOLUME SAMPLING SYSTEM WATER CONDENSATION  

EPA Science Inventory

Combustion of organic motor vehicle fuels produces carbon dioxide and water (H2O) vapor (and also products of incomplete combustion, e.g. hydrocarbons and carbon monoxide, at lower concentrations). he Constant Volume Sampling (CVS) system, commonly used to condition auto exhaust ...

442

COST FOR WATER SUPPLY DISTRIBUTION SYSTEM REHABILITATION  

EPA Science Inventory

A major challenge for the society in the twenty-first century will be design, rehabilitation, replacement, and optimal management of drinking water distribution systems. A recent survey conducted by the USEPA found that $138B will be needed to maintain and replace existing drinki...

443

LUX - A recirculating linac-based ultrafast X-ray source  

SciTech Connect

We describe the design of a proposed source of ultra-fast synchrotron radiation x-ray pulses based on a recirculating superconducting linac, with an integrated array of ultrafast laser systems. The source produces x-ray pulses with duration of 10-50 fs at a 10 kHz repetition rate, with tunability from EUV to hard x-ray regimes, and optimized for the study of ultra-fast dynamics. A high-brightness rf photocathode provides electron bunches. An injector linac accelerates the beam to the 100 MeV range, and is followed by four passes through a 700 MeV recirculating linac. Ultrafast hard x-ray pulses are obtained by a combination of electron bunch manipulation, transverse temporal correlation of the electrons, and x-ray pulse compression. EUV and soft x-ray pulses as short as 10 fs are generated in a harmonic-cascade free electron laser scheme.

Corlett, J.N.; Barletta, W.A.; DeSantis, S.; Doolittle, L.; Fawley, W.M.; Green, M.A.; Heimann, P.; Leone, S.R.; Lidia, S.; Li, D.; Parmigiani, F.; Ratti, A.; Robinson, K.; Schoenlein, R.; Staples, J.; Wan, W.; Wells, R.; Wilcox, R.; Wolski, A.; Zholents, A.

2003-08-01

444

Removal of acidic pharmaceuticals within a nitrifying recirculating biofilter.  

PubMed

The fate of pharmaceutically active compounds (PhACs) in wastewater treatment systems is an area of increasing concern. Little research has been done to understand this issue in rural or decentralized communities. The objective of this research was to examine the ability of a bench scale nitrifying recirculating biofilter (RBF) to remove four acidic PhACs: gemfibrozil, naproxen, ibuprofen and diclofenac from secondary treated municipal wastewater at concentrations of 20 and 200?g/L. The average removals in this study were between 92 and 99% for ibuprofen, 89 and 99% for naproxen, 62 and 92% for gemfibrozil and 40 and 76% for diclofenac, which is consistent with literature. Ibuprofen and naproxen were largely removed through biological transformation; whereas gemfibrozil and diclofenac showed more variable removal, likely due to both biological transformation and sorption processes. PhAC removal in the RBFs was repeatable between trials, robust and responsive to system upsets, and the presence of PhACs as a single compound versus mixtures had no impact on PhAC removal efficiency. In summary, this study indicates that RBFs as a nitrifying stage of a multi-stage filtration process could be a viable technology for removal of some acidic pharmaceuticals in small onsite wastewater treatment facilities. PMID:24727009

Krkošek, W H; Payne, S J; Gagnon, G A

2014-05-30

445

Aircraft Recirculation Filter for Air-Quality and Incident Assessment  

PubMed Central

The current research examines the possibility of using recirculation filters from aircraft to document the nature of air-quality incidents on aircraft. These filters are highly effective at collecting solid and liquid particulates. Identification of engine oil contaminants arriving through the bleed air system on the filter was chosen as the initial focus. A two-step study was undertaken. First, a compressor/bleed air simulator was developed to simulate an engine oil leak, and samples were analyzed with gas chromatograph-mass spectrometry. These samples provided a concrete link between tricresyl phosphates and a homologous series of synthetic pentaerythritol esters from oil and contaminants found on the sample paper. The second step was to test 184 used aircraft filters with the same gas chromatograph-mass spectrometry system; of that total, 107 were standard filters, and 77 were nonstandard. Four of the standard filters had both markers for oil, with the homologous series synthetic pentaerythritol esters being the less common marker. It was also found that 90% of the filters had some detectable level of tricresyl phosphates. Of the 77 nonstandard filters, 30 had both markers for oil, a significantly higher percent than the standard filters. PMID:25641977

Eckels, Steven J.; Jones, Byron; Mann, Garrett; Mohan, Krishnan R.; Weisel, Clifford P.

2015-01-01

446

A Water Recovery System Evolved for Exploration  

NASA Technical Reports Server (NTRS)

A new water recovery system designed towards fulfillment of NASA's Vision for Space Exploration is presented. This water recovery system is an evolution of the current state-of-the-art system. Through novel integration of proven technologies for air and water purification, this system promises to elevate existing technology to higher levels of optimization. The novel aspect of the system is twofold: Volatile organic contaminants will be removed from the cabin air via catalytic oxidation in the vapor phase, prior to their absorption into the aqueous phase, and vapor compression distillation technology will be used to process the condensate and hygiene waste streams in addition to the urine waste stream. Oxidation kinetics dictate that removal of volatile organic contaminants from the vapor phase is more efficient. Treatment of the various waste streams by VCD will reduce the load on the expendable ion exchange and adsorption media which follow, and on the aqueous-phase volatile removal assembly further downstream. Incorporating these advantages will reduce the weight, volume, and power requirements of the system, as well as resupply.

ORourke, Mary Jane E.; Perry, Jay L.; Carter, Donald L.

2006-01-01

447

Practical design and application of airlift technology for aquaculture reuse systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

Air-lift technology to support water movement in low-head water treatment units for recirculating aquacultures systems provides an energy efficient alternative to the use of centrifugal pumps. The benefits of air-lift are further realized when electrical requirements for aeration, CO2 degassing, and...

448

Biotreatment of red water with fungal systems  

SciTech Connect

Red water generated during the manufacture of trinitrotoluene (TNT) is an environmental concern because it contaminates ground surfaces and groundwaters. Past methods for the management of this hazardous waste stream did not meet pollution compliance or were not cost effective. Biodegradation of TNT by bacteria has been reported, but no conclusive evidence supports its biotransformation to harmless products or its complete mineralization. The lignin peroxidase (ligninase) secreted by the white rot fungus (Phanerochaete chrysosporium) has been shown to degrade a broad spectrum of organic pollutants. In this study, the efficacy of treating red water with the P. chrysosporium system was investigated.

Tsai, TenLin S.; Turner, R.J.; Sanville, C.J.

1990-01-01

449

Acid mine water aeration and treatment system  

DOEpatents

An in-line system is provided for treating acid mine drainage which basically comprises the combination of a jet pump (or pumps) and a static mixer. The jet pump entrains air into the acid waste water using a Venturi effect so as to provide aeration of the waste water while further aeration is provided by the helical vanes of the static mixer. A neutralizing agent is injected into the suction chamber of the jet pump and the static mixer is formed by plural sections offset by 90 degrees.

Ackman, Terry E. (Finleyville, PA); Place, John M. (Bethel Park, PA)

1987-01-01

450

Bolivian villagers embrace new water system.  

PubMed

The USAID-CARE Bolivia Child Survival and Rural Sanitation Project brought water to Tauca, a community on the shores of Lake Titicaca. Water is used for washing hands and vegetables which leads to better hygiene and nutrition and is crucial in view of the current cholera epidemic in South America. Farmers often start small irrigation projects for vegetable gardens. A gravity-pumped water system was designed by a CARE engineer but built of local materials by local people in the Bolivian village of Phorejoni Junco. 2 community-trained water operators and 2 health workers visit each home and inspect the sanitation system every month. Llamacachi, a model community with 77 families, has built a clinic with minimal material and labor commitments and additional money from water fees. All 17 children under the age of 5 have received health cards. Only 10% of the children are malnourished, and half of the 79 community mothers know how to prepare oral rehydration fluid for children with diarrhea. In 1989 the CARE project, funded by USAID, set out to improve the health and self-sufficiency of 48,000 people in 160 communities in the Bolivian departments of La Paz, Cochabamba, and Santa Cruz. A major objective was to better the survival rates of children under age 5 by constructing water supply systems, reinforcing community organizations and improving hygiene. In Bolivia fewer than 31% of the rural population has water services, fewer than 13% of the people have latrines, and fewer than 30% have access to health services. The mortality rate of children under age 5 is 100/1000, and 75% of those deaths are related to diarrhea or parasitic illness. The Bolivia Child Survival Project reduced infant mortality in these communities from 210 deaths to 100 deaths per 1000 children under age 5. CARE's Bolivia Child Survival Project was recently funded for 4 more years to serve an additional 160 communities, demonstrating that a sound child survival program and a focus on health depends on quality water systems. PMID:12286430

Foley, V

1993-04-01

451

Experiments on the operation of a combined aquaculture-algae system  

Microsoft Academic Search

A combined aquaculture-algae system was developed for the purification and reuse of effluent water from intensive fish production\\u000a in a combination of a high-rate algal pond and extensive fishpond. The integrated system was operated as a closed system,\\u000a thus the water demand was reduced through the recirculation of the treated water. The pilot-scale experimental system consisted\\u000a of three different compartments:

Dénes Gál; Ferenc Pekár; Éva Kerepeczki; László Váradi

2007-01-01

452

Biosensor systems for pesticide determination in water  

NASA Astrophysics Data System (ADS)

Different biosensor systems suitable for the determination of pesticides in water are described. They are based on immobilized biological components, which are sensitive to compounds commonly used as pesticides. The biological components in the work described here were microorganisms capable of degrading chlorinated aromatic compounds, cholinesterases which are inhibited by carbamates and organophosphates, and antibodies specific to triazines. They were immobilized on various carriers and were either integrated in automated flow-through systems or developed as disposable electrodes. In this contribution, characteristics features of the different formats are given, e.g., the dependence of the specificity and sensitivity of the system on the biological component.

Bilitewski, Ursula; Bier, Frank F.; Beyersdorf-Radeck, Baerbel; Rueger, Petra; Zischkale, Frank; Schmid, Rolf D.

1993-03-01

453

Operational water management of Rijnland water system and pilot of ensemble forecasting system for flood control  

NASA Astrophysics Data System (ADS)

The Rijnland water system is situated in the western part of the Netherlands, and is a low-lying area of which 90% is below sea-level. The area covers 1,100 square kilometres, where 1.3 million people live, work, travel and enjoy leisure. The District Water Control Board of Rijnland is responsible for flood defence, water quantity and quality management. This includes design and maintenance of flood defence structures, control of regulating structures for an adequate water level management, and waste water treatment. For water quantity management Rijnland uses, besides an online monitoring network for collecting water level and precipitation data, a real time control decision support system. This decision support system consists of deterministic hydro-meteorological forecasts with a 24-hr forecast horizon, coupled with a control module that provides optimal operation schedules for the storage basin pumping stations. The uncertainty of the rainfall forecast is not forwarded in the hydrological prediction. At this moment 65% of the pumping capacity of the storage basin pumping stations can be automatically controlled by the decision control system. Within 5 years, after renovation of two other pumping stations, the total capacity of 200 m3/s will be automatically controlled. In critical conditions there is a need of both a longer forecast horizon and a probabilistic forecast. Therefore ensemble precipitation forecasts of the ECMWF are already consulted off-line during dry-spells, and Rijnland is running a pilot operational system providing 10-day water level ensemble forecasts. The use of EPS during dry-spells and the findings of the pilot will be presented. Challenges and next steps towards on-line implementation of ensemble forecasts for risk-based operational management of the Rijnland water system will be discussed. An important element in that discussion is the question: will policy and decision makers, operator and citizens adapt this Anticipatory Water management, including temporary lower storage basin levels and a reduction in extra investments for infrastructural measures.

van der Zwan, Rene

2013-04-01

454

A new method for determination of apparent kinetics parameters in recirculating packed-bed immobilized enzyme reactors  

Microsoft Academic Search

In this study, a simple and effective technique for characterizing Michaelis–Menten apparent kinetic parameters in packed-bed immobilized enzyme reactors is presented. The apparent kinetic parameters of immobilized glucose oxidase on weak base ion exchanger resin (Duolite A 568) were determined for different substrate flow rates in a recirculation system and compared with those for soluble glucose oxidase. It was observed

Ahmet R. Özdural; Deniz Tanyolaç; Zafer Demircan; ?smail H. Boyaci; Mehmet Mutlu; Colin Webb

2001-01-01

455

Determining the optimum solar water pumping system for domestic use, livestock water, or irrigation  

Technology Transfer Automated Retrieval System (TEKTRAN)

For several years we have field tested many different types of solar powered water pumping systems. In this paper, several steps are given to select a solar-PV water pumping system. The steps for selection of stand-alone water pumping system were: deciding whether a wind or solar water pumping sys...

456

Influence of leachate recirculation on aerobic and anaerobic decomposition of solid wastes.  

PubMed

In this study, the effect of leachate recirculation on aerobic and anaerobic degradation of municipal solid wastes is determined by four laboratory-scale landfill reactors. The options studied and compared with the traditional anaerobic landfill are: leachate recirculation, landfill aeration, and aeration with leachate recirculation. Leachate quality is regularly monitored by the means of pH, alkalinity, total dissolved solids, conductivity, oxidation-reduction potential, chloride, chemical oxygen demand, ammonia, and total Kjeldahl nitrogen, in addition to generated leachate quantity. Aerobic leachate recirculated landfill appears to be the most effective option in the removal of organic matter and ammonia. The main difference between aerobic recirculated and non-recirculated landfill options is determined at leachate quantity. Recirculation is more effective on anaerobic degradation of solid waste than aerobic degradation. Further studies are going on to determine the optimum operational conditions for aeration and leachate recirculation rates, also with the operational costs of aeration and recirculation. PMID:17023112

Bilgili, M Sinan; Demir, Ahmet; Ozkaya, Bestamin

2007-05-01

457

Ozone treatment in a closed culture system for Macrobrachium rosenbergii  

E-print Network

, taste and turbidity are affected by oxidation of organic snd inorganic impurities. Such properties of ozone suggested its application in the maintenance of acceptable quality in the recirculated water of closed culture systems. The use of ozone in a... changes during ozonation, such a test was run in this study using culture media prepared from deionized water and from dechlorinated tap water. The dechlorinated tap water was prepared with addition of thiosulfate and aeration. The salinity of both...

Yamaguchi, Ryoji

2012-06-07

458

Prototype solar heating and hot water systems  

NASA Technical Reports Server (NTRS)

Alternative approaches to solar heating and hot water system configurations were studied, parametrizing the number and location of the dampers, the number and location of the fans, the interface locations with the furnace, the size and type of subsystems, and operating modes. A two-pass air-heating collector was selected based on efficiency and ease of installation. Also, an energy transport module was designed to compactly contain all the mechanical and electrical control components. System performance calculations were carried out over a heating season for the tentative site location at Tunkhnana, Pa. Results illustrate the effect of collector size, storage capacity, and use of a reflector. Factors which affected system performance include site location, insulative quality of the house, and of the system components. A preliminary system performance specification is given.

1977-01-01

459

21 CFR 884.6170 - Assisted reproduction water and water purification systems.  

...Identification. Assisted reproduction water purification systems are devices...quality, sterile, pyrogen-free water for reconstitution of media...embryos. These devices also include bottled water ready for reconstitution...

2014-04-01

460

21 CFR 884.6170 - Assisted reproduction water and water purification systems.  

Code of Federal Regulations, 2012 CFR

...Identification. Assisted reproduction water purification systems are devices...quality, sterile, pyrogen-free water for reconstitution of media...embryos. These devices also include bottled water ready for reconstitution...

2012-04-01

461

21 CFR 884.6170 - Assisted reproduction water and water purification systems.  

Code of Federal Regulations, 2013 CFR

...Identification. Assisted reproduction water purification systems are devices...quality, sterile, pyrogen-free water for reconstitution of media...embryos. These devices also include bottled water ready for reconstitution...

2013-04-01

462

21 CFR 884.6170 - Assisted reproduction water and water purification systems.  

Code of Federal Regulations, 2011 CFR

...Identification. Assisted reproduction water purification systems are devices...quality, sterile, pyrogen-free water for reconstitution of media...embryos. These devices also include bottled water ready for reconstitution...

2011-04-01

463

Epidemiology of urban water distribution systems  

NASA Astrophysics Data System (ADS)

water distribution systems worldwide contain numerous old and fragile pipes that inevitably break, flood streets and damage property, and disrupt economic and social activities. Such breaks often present dramatically in temporal clusters as occurred in Los Angeles during 2009. These clustered pipe breaks share many characteristics with human mortality observed during extreme climatological events such as heat waves or air pollution. Drawing from research and empirical studies in human epidemiology, a framework is introduced to analyze the time variations of disruptive pipe breaks that can help water agencies better understand clustered pipe failures and institute measures to minimize the disruptions caused by them. It is posited that at any time, a cohort of the pipes comprising the water distribution system will be in a weakened state due to fatigue and corrosion. This frail cohort becomes vulnerable during normal operations and ultimately breaks due to rapid increase in crack lengths induced by abnormal stressors. The epidemiological harvesting model developed in this paper simulates an observed time series of monthly pipe breaks and has both explanatory and predictive power. It also demonstrates that models from nonengineering disciplines such as medicine can provide improved insights into the performance of infrastructure systems.

Bardet, Jean-Pierre; Little, Richard

2014-08-01

464

Demonstration of split-flow ventilation and recirculation as flow-reduction methods in an Air Force paint spray booth. Final technical report, February 1991-October 1992  

SciTech Connect

During a series of painting operations in a horizontal-flow paint spray booth at Travis AFB, CA, baseline concentrations of four classes of toxic airborne pollutants were measured at 24 locations across a plane immediately forward of the exhaust filters, in the exhaust duct, and inside and outside the respirator in the painter`s breathing zone (BZ). The resulting data were analyzed and used to design a modified ventilation system that (1) separates a portion of the exhaust exiting the lower portion of the booth, which contains a concentration of toxic pollutants greater than the average at the exhaust plane (split-flow); and (2) provides an option to return the flow from the upper portion of the exhaust to the intake plenum for mixing with fresh air and recirculation through the booth (recirculation). After critical review by cognizant Air Force offices and an experimental demonstration showing that a flame ionization detector monitoring the air entering the booth is able to detect excursions above the equivalent exposure limit for the solvents in the paint, the exhaust duct was reconfigured for split-flow and recirculating ventilation. A volunteer painter was briefed on the increased risk of exposure during recirculation, and on the purposes and possible benefits of this study. He then signed an informed consent form before participating in the recirculation tests. A series of tests generally equivalent to the baseline series was conducted during split-flow and recirculating ventilation, and three tests were performed during only split-flow ventilation.

Hughes, S.; Ayer, J.; Sutay, R.

1994-07-01

465

EPANET - AN ADVANCED WATER QUALITY MODELING PACKAGE FOR DISTRIBUTION SYSTEMS  

EPA Science Inventory

EPANET is a third generation software package for modeling water quality within drinking water distribution systems. he program performs extended period simulation of hydraulic and water quality conditions within pressurized pipe networks. n addition to substance concentration wa...

466

Identification of water quality changes in a water system - limitations and perspectives  

Microsoft Academic Search

From the abstraction point and the entrance of water in a Water System (WS) till its discharge back to the environment, water passes through a number of treatments and uses that directly affect its quality. The water quality changes several times while the water returning to the environment at a discharge point into the sea, a lake or a river

DEMETRIS F. LEKKAS

2005-01-01

467

SMALL SYSTEM STUDIES (WATER SUPPLY AND WATER RESOURCES DIVISION)  

EPA Science Inventory

To support and help in the struggle to improve the quality of drinking water in the U.S. and abroad (China and South America), the National Risk Management Research Laboratory's Water Supply and Water Resources Division (WSWRD) uses the USEPA Test and Evaluation (T&E) Facility lo...

468

BENEFITS OF MAINTAINING A CHLORINE RESIDUAL IN WATER SUPPLY SYSTEMS  

EPA Science Inventory

The protection afforded the water consumer by the maintenance of a chlorine residual in water distribution systems was evaluated in laboratory holding tanks and reservoirs and existing municipal water distribution systems. In the laboratory studies, tap water, adjusted to the app...

469

Microbial growth control in water hydraulic systems by conventional filtration  

Microsoft Academic Search

Water hydraulic systems use water as a pressure medium instead of oil. One of the factors limiting the applicability of water hydraulics is microbial growth in the pressure medium and on the surfaces of the system. The aim of this work was to study the potential of conventional hydraulic filters and different filter materials in controlling microbial growth in water

SH Varjus; H Riipinen; SM Soini; KT Koskinen; MJ Vilenius; JA Puhakka

2004-01-01

470

Blood recirculation in temporary central catheters for acute hemodialysis.  

PubMed

The low-flow method has been shown as a reliable evaluation of access recirculation. Few data is available on temporary central catheter blood recirculation; results of 2% and 4% have been reported in subclavian, 10% in 24 cm long femoral, and 18% in 15 cm long femoral catheters, mostly in indwelling catheters for chronic hemodialysis. The purpose of this prospective study was to evaluate blood recirculation in a larger number of recently inserted temporary intravenous catheters for acute hemodialysis, comparing subclavian and femoral sites. Fifty blood recirculation measurements were performed in 38 different temporary central venous dialysis catheters inserted in thirty-one critically ill patients from medical and surgical intensive care units presenting acute renal failure supported by intermittent hemodialysis. All the catheters used were well-functioning 11.5 French dual lumen Quinton of 13.5 or 19.5 cm length. Catheters presenting mechanical dysfunction, which did not allow a blood flow rate of 300 ml/min or for which lines had to be reversed were excluded from the analysis. Access blood recirculation was measured shortly after catheter insertion according to the low flow method applied after the first 30 minutes of hemodialysis at a blood flow rate of 300 ml/min. Mean blood recirculation for the 50 measurements was 10.3 +/- 9.2%. It was significantly higher in the 26 femoral catheters than in the 24 subclavian catheters, reaching respective means of 16.1 +/- 9.1% and 4.1 +/- 3.6% (p = 0.0001). Blood recirculation rate was not different between 13.5 cm and 19.5 cm long subclavian catheters (3.0 +/- 2.6%, n = 13, versus 5.4 +/- 4.3%, n = 11, respectively), but was significantly higher in 13.5 cm long femoral catheters (22.8 +/- 9.1%, n = 9, versus 12.6 +/- 6.9%, n = 17) (p = 0.004). Blood recirculation was measured on two separate occasions in 12 catheters randomly selected (5 femoral and 7 subclavian catheters); the obtained results were reproducible with a mean difference of only 2.1 +/- 1.8% between the two measurements and a correlation of 0.96. The mean time elapsed between catheter insertion and recirculation assessment was 2.2 +/- 3.1 days and was similar for femoral and subclavian catheters. No correlation was found between the percentage of recirculation and the arterial and venous resistances recorded during dialysis session or with the time from catheter insertion. Mean urea reduction ratio (URR) for the 50 dialysis sessions was 57.8 +/- 13.0%. It was significantly higher for sessions performed with subclavian than with femoral catheters (62.5 +/- 10.9%, n = 24, versus 54.5 +/- 14.2%, n = 26) (p = 0.03). In conclusion, the expected blood recirculation in well-functioning and recently inserted temporary dialysis catheters is under 5% for subclavian, over 12% in 19.5 cm femoral, and over 22% in shorter 13.5 cm femoral catheters at a blood flow rate of 300 ml/min. The consequently reduced dialysis efficiency with femoral catheters is another factor to be considered in the choice of a site for temporary dialysis catheter insertion in acute renal failure patients, particularly when dialysis dose delivery is a priority, such as intoxication cases treated by extracorporeal therapy. PMID:8738663

Leblanc, M; Fedak, S; Mokris, G; Paganini, E P

1996-05-01

471

21 CFR 1250.42 - Water systems; constant temperature bottles.  

Code of Federal Regulations, 2012 CFR

(a) The water system, whether of the pressure or gravity type, shall be complete and closed from the filling ends to the discharge taps, except for protected vent openings. The water system shall be protected against...

2012-04-01

472

Installation package for a sunspot cascade solar water heating system  

NASA Technical Reports Server (NTRS)

Solar water heating systems installed at Tempe, Arizona and San Diego, California are described. The systems consist of the following: collector, collector-tank water loop, solar tank, conventional tank, and controls. General guidelines which may be utilized in development of detailed installation plans and specifications are provided along with instruction on operation, maintenance, and installation of solar hot water systems.

1980-01-01

473

STATE OF CALIFORNIA SOLAR DOMESTIC HOT WATER SYSTEMS (SDHW)  

E-print Network

STATE OF CALIFORNIA SOLAR DOMESTIC HOT WATER SYSTEMS (SDHW) CEC- CF-6R-MECH-02 (Revised 08/09) CALIFORNIA ENERGY COMMISSION INSTALLATION CERTIFICATE CF-6R-MECH-02 Solar Domestic Hot Water Systems (SDHW 2009 SOLAR HOT WATER HEATING SYSTEMS: SRCC Certified Mfr Name & Model Number Net Solar Fraction (from

474

Installation package for a solar heating and hot water system  

NASA Technical Reports Server (NTRS)

Development and installation of two commercial solar heating and hot water systems are reported. The systems consist of the following subsystems: collector, storage, transport, hot water, auxiliary energy and controls. General guidelines are provided which may be utilized in development of detailed installation plans and specifications. In addition, operation, maintenance and repair of a solar heating and hot water system instructions are included.

1978-01-01

475

33 CFR 159.127 - Safety coliform count: Recirculating devices.  

...devices. Thirty-eight of forty samples of flush fluid from a recirculating device must have less than 240 fecal coliform bacteria per 100 milliliters. These samples must be collected in accordance with § 159.123(b) and tested in accordance with...

2014-07-01

476

33 CFR 159.127 - Safety coliform count: Recirculating devices.  

Code of Federal Regulations, 2012 CFR

...devices. Thirty-eight of forty samples of flush fluid from a recirculating device must have less than 240 fecal coliform bacteria per 100 milliliters. These samples must be collected in accordance with § 159.123(b) and tested in accordance with...

2012-07-01

477

33 CFR 159.127 - Safety coliform count: Recirculating devices.  

Code of Federal Regulations, 2011 CFR

...devices. Thirty-eight of forty samples of flush fluid from a recirculating device must have less than 240 fecal coliform bacteria per 100 milliliters. These samples must be collected in accordance with § 159.123(b) and tested in accordance with...

2011-07-01

478

The effect of flow recirculation on abdominal aortic aneurysm  

NASA Astrophysics Data System (ADS)

The presences of flow recirculation at the abdominal aortic aneurysm (AAA) region yield the unpredictable failure of aneurismal wall. The failure of the aneurismal wall is closely related to the hemodynamic factor. Hemodynamic factor such as pressure and velocity distribution play a significance role of aneurysm growth and rupture. By using the computational approach, the influence of hemodynamic factor is investigated using computational fluid dynamic (CFD) method on the virtual AAA model. The virtual 3D AAAs model was reconstructed from Spiral Computed Tomography scan (CT-scan). The blood flow is assumed as being transient, laminar and Newtonian within a rigid section of the vessel. The blood flow also driven by an imposed of pressure gradient in the form of physiological waveform. The pulsating blood flow is also considered in this simulation. The results on pressure distribution and velocity profile are analyzed to interpret the behaviour of flow recirculation. The results show the forming of vortices is seen at the aneurysm bulge. This vortices is form at the aneurysm region then destroyed rapidly by flow recirculation. Flow recirculation is point out much higher at distal end of aneurysm closed to iliac bifurcation. This phenomenon is managed to increase the possibility of aneurysm growth and rupture.

Taib, Ishkrizat; Amirnordin, Shahrin Hisham; Madon, Rais Hanizam; Mustafa, Norrizal; Osman, Kahar

2012-06-01

479

Use of low temperature blowers for recirculation of hot gases  

DOEpatents

An apparatus is described for maintaining motors at low operating temperatures during recirculation of hot gases in fuel cell operations and chemical processes such as fluidized bed coal gasification. The apparatus includes a means for separating the hot process gas from the motor using a secondary lower temperature gas, thereby minimizing the temperature increase of the motor and associated accessories.

Maru, H.C.; Forooque, M.

1982-08-19

480

Exhaust gas recirculation valve device for an internal combustion engine  

Microsoft Academic Search

An exhaust gas recirculation valve device is described for an exhaust gas cleaning apparatus of an internal combustion engine for an automobile. A diaphragm mechanism is mounted on a body for operating the valve device. The diaphragm mechanism has a diaphragm and has, on both sides of the diaphragm, chambers which should be connected to the respective engine ports. One

M. Ando; K. Katow; M. Yamazaki

1977-01-01

481

Amplified recirculating circuits for pseudo-continuous wave generation  

Microsoft Academic Search

An analysis of amplified recirculating structures for producing a pseudo-continuous wave, PCW, signal is presented. Experimentations with amplification provided by EDFA and SOA are shown. Both the hold-on function and the switch-off function are analyzed. The comparison between structures with different amplifiers shows better duration performances for EDFAs, but faster all-optical operation capabilities for SOAs.

Paola Parolari; Lucia Marazzi; Pierpaolo Boffi; Mario Martinelli

1999-01-01