Science.gov

Sample records for dewatering

  1. Dewatering of fine coal

    SciTech Connect

    Hogg, R.

    1995-10-01

    The factors which control the dewatering of fine coal by gravity/centrifugal drainage and by gas displacement (vacuum/hyperbaric filtration) are evaluated. A generalized model is presented and used to describe dewatering kinetics and to establish dewatering limits. Applications to the design of dewatering systems for fine coal dewatering are discussed.

  2. Flocculation and dewatering

    SciTech Connect

    Scheiner, B.J. ); Ince, D. )

    1990-05-01

    This article deals with flocculation and dewatering and the developments in this field during 1989. Particular attention is paid to fine coal and a discussion of the international viewpoint on this subject is given.

  3. Sludge dewatering technology

    SciTech Connect

    Weismantel, G.E.

    1993-04-01

    Sludge is an environmental dilemma for many industries, from the process and power industries to the paint and paper industries. Sludge problems exist in production pits and tank bottoms, in plating plants and sewage treatment plants. Flue gas desulfurization systems create enormous amounts of sludge. Dewatering sludge is a multi-billion dollar industry. Sludge dewatering is rarely a single-step process. It can involve several steps, ranging from sludge flocculation and thickening to centrifugation or hydrocycling, clarification, settling and filtering. Sludge dewatering requires an understanding of three major components: the feed stock, the dewatering technology, and the ultimate reuse or disposal of the final product. The characteristics of the feed are important because each dewatering technology reacts differently depending on whether the feed stream is dilute or thick, abrasive or corrosive, fibrous or gelatinous. In addition, factors such as the quantity of feed generated, whether the process is batch or continuous, and minimum and maximum production rates are critical to the choice of dewatering technology. Knowing how the final product will be reused or disposed of helps further narrow the options.

  4. Dewatering of fine coal

    SciTech Connect

    Sastry, K.V.S. . Dept. of Materials Science and Mineral Engineering)

    1991-01-01

    Fine coal dewatering is one of the most pressing problem facing the coal cleaning industry. This project was undertaken with the objective of improving the dewatering process with surface chemical activation by primarily understanding the fundamental and process engineering aspects of vacuum filtration. Specific tasks for this project included -- development of an experimental apparatus and procedure to yield highly reproducible results and extensive data from each test, detailed experimental investigation of the dewatering characteristics of coal fines with and without the addition of flocculants and surfactants, and under different operating conditions, and finally identification and establishment of the physical limits of mechanical dewatering. Following are the significant conclusions from the study: Fineness and size distribution of the coal fines have the most significant influence on the coal dewatering process; usage of flocculants and surfactants is almost essential in reducing the cake moisture and in increasing the filter throughputs; based on the experimental data and the literature information, the existence of an asymptotic limit for filter cake moisture correlatable with a capillary number of the filter cake was identified. 66 refs., 23 figs., 7 tabs.

  5. Dewatering blastholes cuts explosives costs

    SciTech Connect

    Pishaw, S.R.

    1987-11-01

    The author discusses ways to use ANFO inexpensively. They say there are several advantages of dewatering and that there are two primary methods of dewatering blastholes or blasting areas. One method is to use pumps and poly sleeving or liners. The other method is presplit dewatering. The author lists some guidelines for presplitting for information, consideration, and discussion. Often larger mining operations require a combination of presplitting and dewatering with blasthole pumps.

  6. Pumps to reduce dewatering costs

    SciTech Connect

    Stidger, R.W.

    1983-09-01

    Pumps for effective mine dewatering are discussed. The conditions are outlined in underground and surface dewatering (large volume, abrassive and/or corrosive particle content) which will affect the choice of pump. Self priming centrifugal pumps, submerged and multistage pumps are compared for underground and surface dewatering.

  7. Advanced Dewatering Systems Development

    SciTech Connect

    R.H. Yoon; G.H. Luttrell

    2008-07-31

    A new fine coal dewatering technology has been developed and tested in the present work. The work was funded by the Solid Fuels and Feedstocks Grand Challenge PRDA. The objective of this program was to 'develop innovative technical approaches to ensure a continued supply of environmentally sound solid fuels for existing and future combustion systems with minimal incremental fuel cost.' Specifically, this solicitation is aimed at developing technologies that can (i) improve the efficiency or economics of the recovery of carbon when beneficiating fine coal from both current production and existing coal slurry impoundments and (ii) assist in the greater utilization of coal fines by improving the handling characteristics of fine coal via dewatering and/or reconstitution. The results of the test work conducted during Phase I of the current project demonstrated that the new dewatering technologies can substantially reduce the moisture from fine coal, while the test work conducted during Phase II successfully demonstrated the commercial viability of this technology. It is believed that availability of such efficient and affordable dewatering technology is essential to meeting the DOE's objectives.

  8. Energy demand in sludge dewatering.

    PubMed

    Chu, C P; Lee, D J; Chang, C Y

    2005-05-01

    This work investigates the energy required to dewater a suspension, i.e., activated sludge dewatered by centrifugation or consolidation. Total energy input to the suspension from the dewatering device, bond strength between adjacent water and solid surface, and intra-cake friction loss were evaluated for original and flocculated sludges. In centrifugal dewatering, most energy input during the initial stage was consumed by overcoming process irreversibility other than intra-cake friction, and, thereby, had a low energy efficiency. To increase centrifuge speed or to flocculate the sludge at optimal flocculant dosage would yield a high-energy input. In the consolidation test, most energy input at the initial stage was consumed in breaking down the bond strength until the moisture content reduced to less than the critical content. During subsequent dewatering stages, friction loss became the dominant source of energy loss. Dewatering sludge with high-energy efficiency is beneficial to optimally operate a dewatering process. PMID:15899284

  9. Thermal dryer dewaters solids

    SciTech Connect

    DiMascio, F.J.; Burrowes, P.A.

    1993-09-01

    Solids incineration is traditionally an energy-intensive solids handling process at wastewater treatment plants. To reduce energy costs, the Buffalo (N.Y.) Sewer Authority has added an indirect thermal dryer to its treatment plant to dewater solids before incineration. In the first 3 months of operation, the authority reduced its solids inventory from 634,400 to 227,300 kg. Solids processed in the plant`s multiple-hearth incinerators varied from 11 to 12.75 wet Mg/hr at feed concentrations averaging 21% total solids. And, the dryer was operated with less than 5% downtime. The cost of this indirect thermal dryer system, including construction and equipment, was $995,000. 1 fig., 2 tabs.

  10. Dewatering Peat With Activated Carbon

    NASA Technical Reports Server (NTRS)

    Rohatgi, N. K.

    1984-01-01

    Proposed process produces enough gas and carbon to sustain itself. In proposed process peat slurry is dewatered to approximately 40 percent moisture content by mixing slurry with activated carbon and filtering with solid/liquid separation techniques.

  11. PILOT INVESTIGATION OF SECONDARY SLUDGE DEWATERING ALTERNATIVES

    EPA Science Inventory

    A pilot investigation of biological sludge thickening and dewatering alternatives, including pressure filtration, precoat vacuum filtration, filter belt pressing, capillary suction, dewatering, gravity filtration, centrifugation, and ultrafiltration has been conducted on waste ac...

  12. Quantification of wastewater sludge dewatering.

    PubMed

    Skinner, Samuel J; Studer, Lindsay J; Dixon, David R; Hillis, Peter; Rees, Catherine A; Wall, Rachael C; Cavalida, Raul G; Usher, Shane P; Stickland, Anthony D; Scales, Peter J

    2015-10-01

    Quantification and comparison of the dewatering characteristics of fifteen sewage sludges from a range of digestion scenarios are described. The method proposed uses laboratory dewatering measurements and integrity analysis of the extracted material properties. These properties were used as inputs into a model of filtration, the output of which provides the dewatering comparison. This method is shown to be necessary for quantification and comparison of dewaterability as the permeability and compressibility of the sludges varies by up to ten orders of magnitude in the range of solids concentration of interest to industry. This causes a high sensitivity of the dewaterability comparison to the starting concentration of laboratory tests, thus simple dewaterability comparison based on parameters such as the specific resistance to filtration is difficult. The new approach is demonstrated to be robust relative to traditional methods such as specific resistance to filtration analysis and has an in-built integrity check. Comparison of the quantified dewaterability of the fifteen sludges to the relative volatile solids content showed a very strong correlation in the volatile solids range from 40 to 80%. The data indicate that the volatile solids parameter is a strong indicator of the dewatering behaviour of sewage sludges. PMID:26003332

  13. Dewatering of fine coal using hyperbaric filter

    SciTech Connect

    Yang, J.; Wang, X.H.; Parekh, B.K.

    1995-12-31

    Removal of moisture from ultra-fine clean coal (minus 100 mesh) to below 20% level is difficult using conventional dewatering equipment. This paper describes a couple of dewatering approaches which were found to be effective in providing filter cakes containing less than 20% moisture. These approaches involve addition of metal ion-surfactant, and split size dewatering of coal without addition of any reagent.

  14. Coal filtration process and dewatering aids therefore

    SciTech Connect

    Keys, R.O.

    1990-01-09

    This patent describes an improvement in a method for dewatering an aqueous slurry of solid coal particulates wherein the aqueous slurry contains between about 10 and 60 percent of solid coal particulates and a dewatering aid is added to the slurry followed by vacuum filtration thereof to produce a filter cake of the coal particulates. The improvement for lowering the water content of the filter cake comprises adding to the slurry prior to filtration an effective amount of a dewatering aid selected.

  15. Dewatering studies of fine clean coal

    SciTech Connect

    Parekh, B.K.

    1991-01-01

    The main objective of the present research program is to study and understand dewatering characteristics of ultrafine clean coal obtained using the advanced column flotation technique from the Kerr-McGee's Galatia preparation plant fine coal waste stream. It is also the objective of the research program to utilize the basic study results, i.e., surface chemical, particle shape particle size distribution, etc., in developing a cost-effective dewatering method. The ultimate objective is to develop process criteria to obtain a dewatered clean coal product containing less that 20 percent moisture, using the conventional vacuum dewatering equipment. (VC)

  16. SURFACE PHENOMENA IN THE DEWATERING OF COAL

    EPA Science Inventory

    The influence of certain surfactants on the dewatering of fine coal has been investigated. The surfactants investigated were found to have a two-fold effect. They were found to effect the pressure differentials required for dewatering in addition to the residual water contents of...

  17. Sewage sludge dewatering using flowing liquid metals

    DOEpatents

    Carlson, L.W.

    1985-08-30

    This invention relates generally to the dewatering of sludge, and more particularly to the dewatering of a sewage sludge having a moisture content of about 50 to 80% in the form of small cellular micro-organism bodies having internally confined water.

  18. DESIGN MANUAL: DEWATERING MUNICIPAL WASTEWATER SLUDGES

    EPA Science Inventory

    This manual discusses the many factors involved in selecting and designing dewatering equipment for organic sludges produced during primary and secondary municipal wastewater treatment. ive-step approach is outlined for the selection and design of the dewatering equipment for eit...

  19. Combined fields dewatering of seaweed (Nereocystis luetkeana)

    SciTech Connect

    Lightfoot, D.G.; Raghavan, G.S.V.

    1994-05-01

    Increasing pressures on our agricultural systems necessitate the investigation of alternative food and feed sources. The ocean coasts of the world provide one potential alternative, as they provide a habitat for millions of tonnes of brown marine algae, or kelp. In this study, a combined fields (mechanical pressure and electro-osmosis) dewatering technique was investigated for dewatering kelp. Electro-osmosis was shown to significantly improve conventional press dewatering of kelp. Dewatering kelp was found to significantly reduce its ash contents and available carbohydrates, and increase its protein, fat, and uronic acid contents. Furthermore, energy costs for producing dried kelp meal were found to be significantly lower if dewatering precedes thermal drying. 35 refs., 9 figs., 3 tabs.

  20. Dewatering of biomaterials by mechanical thermal expression

    SciTech Connect

    Clayton, S.A.; Scholes, O.N.; Hoadley, A.F.A.; Wheeler, R.A.; McIntosh, M.J.; Huynh, D.Q.

    2006-07-01

    Dewatering by mechanical thermal expression (MTE) for a range of materials is explored using a laboratory-scale MTE compression-permeability cell. It is shown that MTE can be used to effectively dewater a range of biomaterials including lignite, biosolids, and bagasse. The underlying dewatering mechanisms relevant to MTE, namely (1) filtration of water expelled due to thermal dewatering, (2) consolidation, and (3) flash evaporation, are discussed. At lower temperatures, the dominating dewatering mechanism is consolidation, but with increasing temperature, thermal dewatering becomes more important. A major focus is an investigation of the effects of processing parameters, including temperature (20 to 200{sup o}C) and pressure (1.5 to 24 MPa), on material permeability, a fundamental dewatering parameter. It is illustrated that permeability is particularly dependent on the processing temperature, owing to changes in both the material structure and the water properties. In addition, a comparison of permeability in the direction of applied force (axial) and perpendicular to the direction of applied force (radial) is presented. It is shown that, due to alignment of particles under the applied force, the permeability and, hence, rate of water removal in the radial direction is greater than in the axial direction. SEM micrographs are presented to illustrate the particle alignment.

  1. Dewatering fine coal slurries by gel extraction

    SciTech Connect

    Gehrke, S.H.; Lyu, Lii-Hurng.

    1990-01-01

    A new technology called gel extraction has been evaluated to determine its economic viability in dewatering the fine and ultrafine coal slurries generated upon separation of sulfur and ash from clean coal during the physical coal cleaning process. Water must be removed from such slurries prior to transportation and combustion but the dewatering costs are substantial, especially for the fine particles below 28 mesh (0.6 mm). Gel extraction is a potential breakthrough in slurry dewatering technology. The goal of this project was to acquire the qualitative and quantitative data needed to estimate the potential of gel extraction for dewatering coal slurries. The specific objectives were to determine the maximum extents of dewatering (minimum surface moisture in the coal product), the clarity of the water removed (minimum solids content), the speed of the dewatering cycles, the service lifetime of the gels, and the factors which influence all of these. With the results obtained, an economic analysis of Ohio coal cleaning plant dewatering technologies was carried out. The polymer gel at the heart of this project, poly (N-isopropylacrylamide) (PNIPA), can swell several times its shrunken weight at 32[degrees]C by absorbing water at 25[degrees]C. In gel extraction, a shrunken NIPA gel is contacted with a slurry at ambient temperature or cooler; the gel swells by absorbing water from the slurry. The gel is then removed from the dewatered slurry and warmed above its critical temperature of 33[degrees]C, which returns it to the shrunken state by releasing the absorbed water. The facts that the gel is reusable and the process is simple and driven by low-grade energy (warm temperatures), and not inherently limited by particle size, made the process an attractive possible alternative to centrifugation, screening, filtration, etc. for slurry dewatering.

  2. Developments in coal dewatering in Australia

    SciTech Connect

    Osborne, D.G.; Davis, J.J.

    1995-10-01

    The Australian coal industry is characterized by efficient fines recovery, and the climate does not dictate the use of thermal drying. With the increasing trend to underground mining and hence finer ROM coal, and market pressures for reduced product moistures, dewatering issues are assuming increasing importance in the Australian coal industry. The greatest potential gains in dewatering performance undoubtedly lie in the treatment of finely sized material. This paper examines the dewatering issues which have been recognized by the Australian coal industry, and describes current Australian research in this field.

  3. SLUDGE DEWATERING AND DRYING ON SAND BEDS

    EPA Science Inventory

    Dewatering of water and wastewater treatment sludges was examined through mathematical modeling and experimental work. The various components of the research include: (1) chemical analyses of water treatment sludges, (2) drainage and drying studies of sludges, (3) a mathematical ...

  4. Solution dewatering with concomitant ion removal

    SciTech Connect

    Peterson, Eric S.; Marshall, Douglas W.; Stone, Mark L.

    2003-08-05

    One of the biggest needs in the separations and waste handling and reduction area is a method for dewatering ion-containing solutions. Unexpectedly, it has been found that phosphazene polymers can discriminate between water and metal ions, allowing water to pass through the membrane while retaining the ions. This unexpected result, along with the inherent chemical and thermal stability of the phosphazene polymers, yields a powerful tool for separating and dewatering metal-ion-containing solutions.

  5. Dewatering in biological wastewater treatment: A review.

    PubMed

    Christensen, Morten Lykkegaard; Keiding, Kristian; Nielsen, Per Halkjær; Jørgensen, Mads Koustrup

    2015-10-01

    Biological wastewater treatment removes organic materials, nitrogen, and phosphorus from wastewater using microbial biomass (activated sludge, biofilm, granules) which is separated from the liquid in a clarifier or by a membrane. Part of this biomass (excess sludge) is transported to digesters for bioenergy production and then dewatered, it is dewatered directly, often by using belt filters or decanter centrifuges before further handling, or it is dewatered by sludge mineralization beds. Sludge is generally difficult to dewater, but great variations in dewaterability are observed for sludges from different wastewater treatment plants as a consequence of differences in plant design and physical-chemical factors. This review gives an overview of key parameters affecting sludge dewatering, i.e. filtration and consolidation. The best dewaterability is observed for activated sludge that contains strong, compact flocs without single cells and dissolved extracellular polymeric substances. Polyvalent ions such as calcium ions improve floc strength and dewaterability, whereas sodium ions (e.g. from road salt, sea water intrusion, and industry) reduce dewaterability because flocs disintegrate at high conductivity. Dewaterability dramatically decreases at high pH due to floc disintegration. Storage under anaerobic conditions lowers dewaterability. High shear levels destroy the flocs and reduce dewaterability. Thus, pumping and mixing should be gentle and in pipes without sharp bends. PMID:25959073

  6. Dewatering of contaminated river sediments

    NASA Technical Reports Server (NTRS)

    Church, Ronald H.; Smith, Carl W.; Scheiner, Bernard J.

    1994-01-01

    Dewatering of slurries has been successfully accomplished by the proper use of polymers in flocculating the fine particulate matter suspended in mineral processing streams. The U.S. Bureau of Mines (USBM) entered into a cooperative research effort with the U.S. Army Corps of Engineers (Corps) for the purpose of testing and demonstrating the applicability of mining flocculation technology to dredging activities associated with the removal of sediments from navigable waterways. The Corps has the responsibility for maintaining the navigable waterways in the United States. Current technology relies primarily on dredging operations which excavate the material from the bottom of waterways. The Corps is testing new dredging technology which may reduce resuspension of sediments by the dredging operation. Pilot plant dredging equipment was tested by the Corps which generated larger quantities of water when compared to conventional equipment, such as the clam shell. The transportation of this 'excess' water adds to the cost of sediment removal. The process developed by the USBM consists of feed material from the barge being pumped through a 4-in line by a centrifugal pump and exiting through a 4-in PVC delivery system. A 1,000-gal fiberglass tank was used to mix the polymer concentrate. The polymer was pumped through a 1-in line using a variable speed progressive cavity pump and introduced to the 4-in feed line prior to passing through a 6-in by 2-ft static mixer. The polymer/feed slurry travels to the clarifying tank where the flocculated material settled to the bottom and allowed 'clean' water to exit the overflow. A pilot scale flocculation unit was operated on-site at the Corps' 'Confined Disposal Facility' in Buffalo, NY.

  7. An innovative concept for dewatering hydro plants

    SciTech Connect

    Lux, F. III; Bakken, J.R. )

    1992-12-01

    A floating bulkhead that works much like an overhead garage door can be a versatile, reusable, and cost-effective tool for dewatering unit intakes or gated spillway bays at hydroelectric facilities. The floating bulkhead consists of a number of individual floating caissons that can be installed separately by stacking them one on top of another, or pinned together with hinges and installed as a unit. A caisson consists of one or more flotation compartments and a water-filled compartment to sink or float it. Each caisson is lowered into the reservoir from an accessible location, such as a boat launch, and towed into position by a boat. The floating bulkhead is especially suited to structures that have no provisions for dewatering or where the existing dewatering structures are no longer serviceable, or in situations where cranes are not available to install stoplogs.

  8. Behavioral responses of freshwater mussels to experimental dewatering

    USGS Publications Warehouse

    Galbraith, Heather S.; Blakeslee, Carrie J.; Lellis, William A.

    2015-01-01

    Understanding the effects of flow alteration on freshwater ecosystems is critical for predicting species responses and restoring appropriate flow regimes. We experimentally evaluated the effects of 3 dewatering rates on behavior of 6 freshwater mussel species in the context of water-removal rates observed in 21 Atlantic Coast rivers. Horizontal movement differed significantly among species and dewatering rates, but a significant species × dewatering interaction suggested that these factors influence movement in complex ways. Species differences in movement were evident only in controls and under slow dewatering rates, but these differences disappeared at moderate and fast dewatering rates. Burrowing behavior did not differ with respect to species identity or dewatering rate. The proportion of individuals that became stranded did not differ among species, but most individuals became stranded under low and moderate dewatering, and all individuals became stranded under fast dewatering. Mortality after stranding differed strongly among species along a gradient from 25% inPyganodon cataracta to 92% in Alasmidonta marginata. Together, these results suggest that species behavior may differ under gradual dewatering, but all species in our study are poorly adapted for rapid dewatering. Most of the 21 rivers we assessed experienced dewatering events comparable to our moderate rate, and several experienced events comparable to our fast rate. Dewatering events that exceed the movement or survival capability of most mussel species can be expected to result in assemblage-wide impacts. Consequently, the rate of water level change may be important in refining target flow conditions for restoration.

  9. Low Cost Dewatering of Waste Slurries

    NASA Technical Reports Server (NTRS)

    Peterson, J. B.; Sharma, S. K.; Church, R. H.; Scheiner, B. J.

    1993-01-01

    The U.S. Bureau of Mines has developed a technique for dewatering mineral waste slurries which utilizes polymer and a static screen. A variety of waste slurries from placer gold mines and crushed stone operations have been successfully treated using the system. Depending on the waste, a number of polymers have been used successfully with polymer costs ranging from $0.05 to $0.15 per 1,000 gal treated. The dewatering is accomplished using screens made from either ordinary window screen or wedge wire. The screens used are 8 ft wide and 8 ft long. The capacity of the screens varies from 3 to 7 gpm/sq. ft. The water produced is acceptable for recycling to the plant or for discharge to the environment. For example, a fine grain dolomite waste slurry produced from a crushed stone operation was dewatered from a nominal 2.5 pct solids to greater than 50 pct solids using $0.10 to $0.15 worth of polymer per 1,000 gal of slurry. The resulting waste water had a turbidity of less than 50 NTU and could be discharged or recycled. The paper describes field tests conducted using the polymer-screen dewatering system.

  10. CHEMICAL PRIMARY SLUDGE THICKENING AND DEWATERING

    EPA Science Inventory

    This report presents the results of a ten month study of the thickening and dewatering characteristics of chemical-primary sludges. Alum-primary and ferric-primary sludges were produced in parallel trains of a pilot plant operated using a municipal wastewater. Each chemical treat...

  11. Vibration screens for dewatering of minerals -- Theory and practice

    SciTech Connect

    Keller, K.; Stahl, W.

    1995-12-31

    Vibration screens are commonly used not only in classifying bulk material but also in dewatering it. The lack of a comprehensive physical theory of dewatering often leads to difficulties in the design and operation of the vibration screens. Firstly, the dewatering of bulk material will be shown, based on a physical model. Because of the oscillatory motion of the liquid in the bulk, the inertial force of the accelerated liquid and the dripping of water out of the bulk or screen must be taken into special consideration. The physical model put forward shows the effect of the various operations parameters of dewatering screens. The comparison between dewatering theory and practice will be shown by measurements using coal, limestone, etc. Dewatering measurements, which have been conducted on a vibration screen, demonstrate that different vibration frequencies and rates of acceleration lead to different residual moistures. Finally, the possibilities of improving vibration dewatering will be described.

  12. Application of amphoteric polyelectrolytes for sludge dewatering

    SciTech Connect

    Watanabe, Y.; Kubo, K.; Sato, S.

    1999-06-08

    Conventional sludge conditioning with polymer flocculants usually involves the addition of either a cationic polymer or a combination of a cationic and an anionic polymer. On the other hand, a combination of a metal coagulant and an amphoteric polymer was found to produce large, mechanically strong flocs. On the basis of this observation and by use of the colloid titration method the efficiency of the sludge charge neutralization with a metal coagulant and the amount of polymer adhered to the sludge particle surfaces were measured to elucidate the mechanism of the amphoteric polymer attachment. This study indicated that amphoteric polymers were roughly divided into two main types by the cation-anion ratio of the polymer according to the efficiency of the charge neutralization. Furthermore, field survey results have demonstrated that a new system gave a two times higher dewatering rate, producing a dewatered sludge cake having a moisture content 2--5% lower than those obtained conventional methods.

  13. SRB dewatering set. [space shuttle boosters revcovery

    NASA Technical Reports Server (NTRS)

    Wickham, R. E.

    1981-01-01

    The system components and operation of the space shuttle solid rocket booster (SRB) dewatering set are described. The SRB dewatering set consists of a nozzle plug, control console, remote control unit, power distribution unit, umbilical cable, interconnect cables, and various handling and storage items. The nozzle plug (NP) is a remotely controlled, tethered underwater vehicle that is launched from the retrieval vessel (RV) by a crane, descends down the side of the SRB, and is positioned below the SRB nozzle. A TV camera mounted at the top of the NP central core is used by the control console operator to visually guide the NP during descent and docking. The NP is then driven up and locked into the nozzle. Compressed air is passed through the umbilical from the RV, through the NP and into the SRB motor. The water inside the SRB is expelled causing the SRB to rotate to a near horizontal attitude on the surface of the water.

  14. Space Shuttle solid rocket booster dewatering system

    NASA Technical Reports Server (NTRS)

    Fishel, K. R.

    1982-01-01

    After the launch of the Space Shuttle, the two solid rocket boosters (SRB's) are jettisoned into the ocean where they float in a spar (vertical) mode. It is cost effective to recover the SRB's. A remote controlled submersible vehicle has been developed to aid in their recovery. The vehicle is launched from a support ship, maneuvered to the SRB, then taken to depth and guided into the rocket nozzle. It then dewaters the SRB, using compressed air from the ship, and seals the nozzle. When dewatered, the SRB floats in a log (horizontal) mode and can be towed to port for reuse. The design of the remote controlled vehicle and its propulsion system is presented.

  15. Dewatering refuse brings profits to Dorchester Coal

    SciTech Connect

    Morgan, M.; Erickson, L.

    1984-09-01

    A belt filter press is discussed which allowed Dorchester Coal's 150 tph preparation plant to meet certain objectives. The minus 28 mesh refuse had to be dewatered further for trucking and spreading in a landfill because it did not conform to regulatory requirements. The press allowed the plant to operate with a closed water circuit, brought the landfill into compliance, and reduced refuse handling problems. Moreover, the belt press system reduced refuse disposal costs.

  16. Electroacoustic dewatering of food and other suspensions

    SciTech Connect

    Kim, B.C.; Zelinski, M.S.; Criner, C.L.; Senapati, N.; Muralidhara, H.S.; Jirjis, B.; Beard, R.E.; Cummings, C.; Chauhan, S.P.

    1989-05-31

    The food processing industry is a large user of energy for evaporative drying due to limited effectiveness of conventional mechanical dewatering machines. Battelle's Electroacoustic Dewatering (EAD) process improves the performance of mechanical dewatering machines by superimposing electric and ultrasonic fields. A two phase development program to demonstrate the benefits of EAD was carried out in cooperation with the food processing industry, the National Food Processors Association (NFPA) and two equipment vendors. In Phase I, laboratory scale studies were carried out on a variety of food suspensions. The process was scaled up to small commercial scale in Phase II. The technical feasibility of EAD for a variety of food materials, without adversely affecting the food properties, was successfully demonstrated during this phase, which is the subject of this report. Two Process Research Units (PRUs) were designed and built through joint efforts between Battelle and two equipment vendors. A 0.5-meter wide belt press was tested on apple mash, corn fiber, and corn gluten at sites provided by two food processors. A high speed citrus juice finisher (a hybrid form of screw press and centrifuge) was tested on orange pulp. These tests were carried out jointly by Battelle, equipment vendors, NFPA, and food processors. The apple and citrus juice products were analyzed by food processors and NFPA. 26 figs., 30 tabs.

  17. Dredging and dewatering sediment containing hazardous and toxic materials

    SciTech Connect

    Askin, R.C.

    1996-12-31

    Dredging is a common method of remediating ponds containing contaminated wastes. However, dewatering of the dredged solids is usually not well integrated with the dredging phase. As a result, overall project efficiency can be poor. Specifically, since dredges deliver material in a widely varying slurry form and since dewatering presses require the delivered material to be uniform, union of the two systems often results in inconsistent operation of the overall process. In an effort to enhance overall dredging and dewatering process production rates as well as minimize the return of suspended solids in the decant water, a new process was developed to provide a consistent dredged sludge for delivery to the press. This paper discusses modifications made to a conventional dredging and dewatering process to improve production rates and dewatering capabilities. These modifications are applicable to any project where efficient solids dewatering is required and where returning decant water must be visually free of suspended solids. 4 figs.

  18. 46 CFR 28.815 - Bilge pumps, bilge piping, and dewatering systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...false Bilge pumps, bilge piping, and dewatering systems. 28.815 Section 28...815 Bilge pumps, bilge piping, and dewatering systems. Instead of meeting the... (e) Each bilge suction line and dewatering system must be fitted with a...

  19. 46 CFR 28.815 - Bilge pumps, bilge piping, and dewatering systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...false Bilge pumps, bilge piping, and dewatering systems. 28.815 Section 28...815 Bilge pumps, bilge piping, and dewatering systems. Instead of meeting the... (e) Each bilge suction line and dewatering system must be fitted with a...

  20. 46 CFR 28.815 - Bilge pumps, bilge piping, and dewatering systems.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...false Bilge pumps, bilge piping, and dewatering systems. 28.815 Section 28...815 Bilge pumps, bilge piping, and dewatering systems. Instead of meeting the... (e) Each bilge suction line and dewatering system must be fitted with a...

  1. 46 CFR 28.815 - Bilge pumps, bilge piping, and dewatering systems.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...false Bilge pumps, bilge piping, and dewatering systems. 28.815 Section 28...815 Bilge pumps, bilge piping, and dewatering systems. Instead of meeting the... (e) Each bilge suction line and dewatering system must be fitted with a...

  2. 46 CFR 28.815 - Bilge pumps, bilge piping, and dewatering systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...false Bilge pumps, bilge piping, and dewatering systems. 28.815 Section 28...815 Bilge pumps, bilge piping, and dewatering systems. Instead of meeting the... (e) Each bilge suction line and dewatering system must be fitted with a...

  3. Improved FGD dewatering process cuts solid wastes

    SciTech Connect

    Moer, C.; Fernandez, J.; Carraro, B.

    2009-08-15

    In 2007, Duke Energy's W.H. Zimmer Station set out to advance the overall performance of its flue gas desulfurization (FGD) dewatering process. The plant implemented a variety of measures, including upgrading water-solids separation, improving polymer program effectiveness and reliability, optimizing treatment costs, reducing solid waste sent to the landfill, decreasing labor requirements, and maintaining septic-free conditions in clarifiers. The changes succeeded in greatly reducing solid waste generation and achieving total annual savings of over half a million dollars per year. 8 figs., 1 tab.

  4. Ultrafine coal single stage dewatering and briquetting process

    SciTech Connect

    Wilson, J.W.; Honaker, R.Q.

    1995-12-31

    It is well known that a large portion of the pyrite particles in the coal seams of the Illinois Basin are finely disseminated within the coal matrix. In order to liberate these micron size pyrite particles, one must use a fine grinding operation. The ultrafine coal particles are difficult to dewater and create problems in coal transportation, as well as in storage and handling at utility plants. The objective of this research project is to combine the ultrafine coal dewatering and briquetting processes into a single stage operation. This will be accomplished by the use of bitumen based emulsions for dewatering and a compaction device for briquetting. During this reporting period, several types of coal samples with various particle size distributions have been tested for use in the dewatering and briquetting processes. Furthermore, various bitumen emulsions have been tested to determine the optimum dewatering reagent. These dewatering and pelletizing tests were carried out using a lab-scale ram extruder. Discharge from the dewatering and briquetting processes was tested to determine compliance with current federal and state requirements. The influence of bitumen emulsion on the sulfur content of coal pellets made were also examined. In addition, a ram extruder which can be operated continuously to simulate a rotary press operation, has been built and is currently being tested for use in the fine coal dewatering and pelletizing process.

  5. Characteristics of biosolids in dimethyl ether dewatering method.

    PubMed

    Oshita, Kazuyuki; Takaoka, Masaki; Nakajima, Yusuke; Morisawa, Shinsuke; Kanda, Hideki; Makino, Hisao; Takeda, Nobuo

    2012-02-01

    In this study, a method for removing water from biosolids that uses dimethyl ether (DME) as an extractant was considered. This study evaluates the applicability of the DME dewatering method to biosolid cakes by using a DME flow-type experimental apparatus. It was found that a high dewatering ratio is clearly achieved by increasing the liquefied DME/biosolid ratio and lowering the liquefied DME linear velocity. As the liquefied DME/biosolid ratio was increased, the carbon content in dewatered biosolid showed a slight decrease and the TOC concentration in separated liquid increased significantly. Finally, the input energy Es to remove 1 kg of water from the biosolid cake, using both the DME dewatering method and the conventional drying method was estimated. The calculation shows that Es for the DME dewatering process is approximately a third of Es for the conventional thermal drying process. PMID:22515061

  6. Predicting the moisture content of coals dewatered by vacuum filters

    SciTech Connect

    Arnold, B.J.

    1995-12-31

    Coal cleaning separations, both size- and gravity-based, rely on the use of water to make the process more efficient. Removal of water from the clean coal product reduces transportation costs, handling problems, and coal utilization problems. Coal cleaning refuse is also dewatered prior to disposal. The coal industry uses a wide range of equipment to dewater coal and refuse streams in cleaning plants, including thickeners, screens, filters, centrifuges, and thermal dryers. Aspen Technology Inc. developed the Coal Cleaning Simulator (CCS) running under ASPEN PLUS{trademark}. Simulator models for coal sizing, cleaning, and dewatering devices were developed by ICF Kaiser Engineers and CQ Inc., with assistance from The Pennsylvania State University. CQ Inc. and Penn State collaborated on the dewatering models. The CCS dewatering models predict the remaining free (surface) moisture of the cake, moisture which is potentially removal by mechanical means. By definition, the free moisture is the difference between total and equilibrium moisture. The equilibrium moisture is considered non-removable. One of the simpler dewatering models in the CCS is the vacuum-disk filter model. This paper highlights the calculation for moisture content in the product from this dewatering device.

  7. Corps Corps River Closure Division District System Mile Structure Start Complete Length Dewatering Notes

    E-print Network

    US Army Corps of Engineers

    Corps Corps River Closure Division District System Mile Structure Start Complete Length Dewatering Dewater and Inspect LRD LRP Allegheny River (AMS) 62.2 Allegheny Lock 9 Apr-12 Apr-12 Y Dewater and Inspect LRD LRP Allegheny River (AMS) 52.6 Allegheny Lock 8 Apr-13 Apr-13 Y Dewater and Inspect LRD LRP

  8. 46 CFR 28.255 - Bilge pumps, bilge piping, and dewatering systems.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...false Bilge pumps, bilge piping, and dewatering systems. 28.255 Section 28...255 Bilge pumps, bilge piping, and dewatering systems. (a) Each vessel must...which water is used must be fitted with dewatering system capable of dewatering the...

  9. 46 CFR 28.255 - Bilge pumps, bilge piping, and dewatering systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...false Bilge pumps, bilge piping, and dewatering systems. 28.255 Section 28...255 Bilge pumps, bilge piping, and dewatering systems. (a) Each vessel must...which water is used must be fitted with dewatering system capable of dewatering the...

  10. 46 CFR 28.255 - Bilge pumps, bilge piping, and dewatering systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...false Bilge pumps, bilge piping, and dewatering systems. 28.255 Section 28...255 Bilge pumps, bilge piping, and dewatering systems. (a) Each vessel must...which water is used must be fitted with dewatering system capable of dewatering the...

  11. 46 CFR 28.255 - Bilge pumps, bilge piping, and dewatering systems.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...false Bilge pumps, bilge piping, and dewatering systems. 28.255 Section 28...255 Bilge pumps, bilge piping, and dewatering systems. (a) Each vessel must...which water is used must be fitted with dewatering system capable of dewatering the...

  12. 46 CFR 28.255 - Bilge pumps, bilge piping, and dewatering systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...false Bilge pumps, bilge piping, and dewatering systems. 28.255 Section 28...255 Bilge pumps, bilge piping, and dewatering systems. (a) Each vessel must...which water is used must be fitted with dewatering system capable of dewatering the...

  13. Dewatering fine coal slurries by gel extraction. Final report

    SciTech Connect

    Gehrke, S.H.; Lyu, Lii-Hurng

    1990-12-31

    A new technology called gel extraction has been evaluated to determine its economic viability in dewatering the fine and ultrafine coal slurries generated upon separation of sulfur and ash from clean coal during the physical coal cleaning process. Water must be removed from such slurries prior to transportation and combustion but the dewatering costs are substantial, especially for the fine particles below 28 mesh (0.6 mm). Gel extraction is a potential breakthrough in slurry dewatering technology. The goal of this project was to acquire the qualitative and quantitative data needed to estimate the potential of gel extraction for dewatering coal slurries. The specific objectives were to determine the maximum extents of dewatering (minimum surface moisture in the coal product), the clarity of the water removed (minimum solids content), the speed of the dewatering cycles, the service lifetime of the gels, and the factors which influence all of these. With the results obtained, an economic analysis of Ohio coal cleaning plant dewatering technologies was carried out. The polymer gel at the heart of this project, poly (N-isopropylacrylamide) (PNIPA), can swell several times its shrunken weight at 32{degrees}C by absorbing water at 25{degrees}C. In gel extraction, a shrunken NIPA gel is contacted with a slurry at ambient temperature or cooler; the gel swells by absorbing water from the slurry. The gel is then removed from the dewatered slurry and warmed above its critical temperature of 33{degrees}C, which returns it to the shrunken state by releasing the absorbed water. The facts that the gel is reusable and the process is simple and driven by low-grade energy (warm temperatures), and not inherently limited by particle size, made the process an attractive possible alternative to centrifugation, screening, filtration, etc. for slurry dewatering.

  14. Disposable sludge dewatering container and method

    DOEpatents

    Cole, Clifford M. (1905 Cottonwood Dr., Aiken, SC 29803)

    1993-01-01

    A device and method for preparing sludge for disposal comprising a box with a thin layer of gravel on the bottom and a thin layer of sand on the gravel layer, an array of perforated piping deployed throughout the gravel layer, and a sump in the gravel layer below the perforated piping array. Standpipes connect the array and sump to an external ion exchanger/fine particulate filter and a pump. Sludge is deposited on the sand layer and dewatered using a pump connected to the piping array, topping up with more sludge as the aqueous component of the sludge is extracted. When the box is full and the free standing water content of the sludge is acceptable, the standpipes are cut and sealed and the lid secured to the box.

  15. 29. VIEW NORTHWEST ON SHELTON SIDE OF DAM DURING DEWATERING. ...

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

    29. VIEW NORTHWEST ON SHELTON SIDE OF DAM DURING DEWATERING. SHELTON GATEHOUSE IN LEFT CENTER. - Ousatonic Water Power Company, Dam & Canals, CT Routes 34 & 108, 1 mile North of Derby-Shelton Bridge, Derby, New Haven County, CT

  16. Pressure, centrifugal, and electrically assisted dewatering of coal

    SciTech Connect

    Bainbridge, N.W.; Johnston, B.K.; Lockhart, N.C.

    1995-10-01

    CSIRO and its collaborators have developed a major R and D project on dewatering of coal. This involves sub-projects on (1) the fundamentals of coal-water associations; (2) reducing the variability of product moisture levels from small coal centrifuges; (3) process mechanisms and optimization for fine coal dewatering; (4) pilot scale testing, engineering development and innovation. Results from each of these sub-projects are presented, and the pilot facility incorporating a vacuum filter, belt press, membrane press, hyperbaric filters and centrifuges, is discussed. The vacuum filter and membrane press can be configured for electric-field assisted dewatering, which provides substantial enhancements in the rate and degree of dewatering for fine coal, coal tailings, and other suspensions.

  17. 3. View southwest at dewatered culvert outlet headwall, with part ...

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

    3. View southwest at dewatered culvert outlet headwall, with part of canal bank removed in back (left) of headwall. - Delaware & Raritan Canal, Ten Mile Run Culvert, 1.5 miles South of Blackwells Road, East Millstone, Somerset County, NJ

  18. Filtration and dewatering: review of literature. [117 references

    SciTech Connect

    Gala, H. B.; Chiang, S. H.

    1980-09-01

    Filtration and dewatering are important aspects of any chemical process involved in producing solid product from a slurry. However, these operations are not studied in as much detail as other industrial operations like distillation, absorption, etc. In the past, the design of filtration equipment was considered more of an art than science. Only in the last few years have attempts been made to understand the fundamental mechanism underlying these operations. In this review, the present status of filtration and dewatering is discussed, particularly concerning the models used for predicting the rate of filtration and dewatering. Effects of various parameters, size of particles in the slurry, their shape and method of cake formation, etc., on the characteristics of these operations are analyzed. A separate chapter on the use of these processes in coal cleaning is included. Dewatering of fine coal and refuse has attracted a great deal of attention in recent years. Special problems associated with dewatering of fine coal are discussed. Enhanced methods of dewatering are reviewed and finally areas requiring further research are highlighted.

  19. Ultrafine coal single stage dewatering and briquetting process

    SciTech Connect

    Wilson, J.W.; Ding, Y.; Tobey, M.

    1995-12-31

    The primary goal of the current physical coal cleaning process is to reduce the ash and sulfur content from the coal, that is, to remove the mineral particles from the coal. In order to separate mineral from coal particles efficiently, the finely disseminated mineral matter must be liberated from the coal matrix with the help of an ultrafine grinding operation. The coal becomes very difficult to dewater because of the small particle size produced. Difficulty in coal transportation as well as in its storage and handling at the utility plants are also problems associated with the small coal particles resulting from ultrafine grinding. During this project, several types of coal samples with various particle size distributions have been tested for use in the dewatering and briquetting processes. Furthermore, various bitumen emulsions have been tested to determine the optimum dewatering reagent. These dewatering and pelletizing tests were carried out using a lab-scale hydraulic compacting device. Discharge from the dewatering and briquetting processes was tested to determine compliance with current federal and state requirements. The influence of bitumen emulsion on the sulfur content of coal pellets made were also examined. In addition, a ram extruder which can be operated continuously to simulate a rotary press operation, has been built and is currently being tested for use in the fine coal dewatering and pelletizing process.

  20. Survival and behaviour of juvenile unionid mussels exposed to thermal stress and dewatering in the presence of

    E-print Network

    Kwak, Thomas J.

    Survival and behaviour of juvenile unionid mussels exposed to thermal stress and dewatering diminished burrowing behaviour significantly in both species (P dewatered treatment water temperature and dewatering may directly impact freshwater mussel abundance by causing mortality

  1. DEVELOPMENT OF DEWATERING AIDS FOR MINERALS AND COAL FINES

    SciTech Connect

    Roe-Hoam Yoon; Ramazan Asmatulu; Ismail Yildirim; William Jansen; Jinmig Zhang; Brad Atkinson; Jeff Havens

    2004-07-01

    MCT has developed a suite of novel dewatering chemicals (or aids) that are designed to cause a decrease in the capillary pressures of the water trapped in a filter cake by (1) decreasing the surface tension of water, (2) increasing the contact angles of the particles to be dewatered, and (3) causing the particles to coagulate, all at the same time. The decrease in capillary pressure in turn causes an increase in the rate filtration, an increase in throughput, and a decrease in pressure drop requirement for filtration. The reagents are used frequently as blends of different chemicals in order to bring about the changes in all of the process variables noted above. The minerals and coal samples tested in the present work included copper sulfide, lead sulfide, zinc sulfide, kaolin clay, talc, and silica. The laboratory-scale test work included studies of reagent types, drying cycle times, cake thickness, slurry temperature, conditioning intensity and time, solid content, and reagent dosages. To better understand the mechanisms involved, fundamental studies were also conducted. These included the measurements of the contact angles of the particles to be dewatered (which are the measures of particle hydrophobicity) and the surface tensions of the filtrates produced from dewatering tests. The results of the laboratory-scale filtration experiments showed that the use of the novel dewatering aids can reduce the moistures of the filter cake by 30 to 50% over what can be achieved using no dewatering aids. In many cases, such high levels of moisture reductions are sufficient to obviate the needs for thermal drying, which is costly and energy intensive. Furthermore, the use of the novel dewatering aids cause a substantial increase in the kinetics of dewatering, which in turn results in increased throughput. As a result of these technological advantages, the novel dewatering aids have been licensed to Nalco, which is one of the largest mining chemicals companies of the world. At least one mineral company is currently using the technology in full-scale plant operation, which has resulted in the shutdown of a thermal dryer.

  2. Electroosmotic dewatering of dredged sediments: bench-scale investigation.

    PubMed

    Reddy, Krishna R; Urbanek, Adam; Khodadoust, Amid P

    2006-01-01

    The Indiana Harbor (Indiana, USA) has not been dredged since 1972 due to lack of a suitable disposal site for dredged sediment. As a result of this, over a million cubic yards of highly contaminated sediment has accumulated in the harbor. Recently, the United States Army Corps of Engineers (USACE) has selected a site for the confined disposal facility (CDF) and is in the process of designing it. Although dredging can be accomplished rapidly, the disposal in the CDF has to be done slowly to allow adequate time for consolidation to occur. The sediment possesses very high moisture content and very low hydraulic conductivity, which cause consolidation to occur slowly. Consolidation of the sediment is essential in order to achieve adequate shear strength of sediments and also to provide enough air space to accommodate the large amount of sediment that requires disposal. Currently, it has been estimated that if a one 3-foot (0.9-m) thick layer of sediment was disposed of at the CDF annually, it would take approximately 10 years to dispose of all the sediment that is to be dredged from the Indiana Harbor. This study investigated the feasibility of using an electroosmotic dewatering technology to accelerate dewatering and consolidation of sediment, thereby allowing more rapid disposal of sediment into the CDF. Electroosmotic dewatering essentially involves applying a small electric potential across the sediment layer, thereby inducing rapid flow as a result of physico-chemical and electrochemical processes. A series of bench-scale electrokinetic experiments were conducted on actual dredged sediment samples from the Indiana Harbor to investigate dewatering rates caused by gravity alone, dewatering rates caused by gravity and electric potential, and the effects of the addition of polymer flocculants on dewatering of the sediments. The results showed that electroosmotic dewatering under an applied electric potential of 1.0VDC/cm could increase the rate of dewatering and consolidation by an order of magnitude as compared to gravity drainage alone. Amending the sediment with polymers at low concentrations (0.5-1% by dry weight) will enhance this dewatering process; however, the optimal polymer concentration and the cost-effectiveness of using polymers should be investigated further. PMID:16139947

  3. Application of electro acoustics for dewatering pharmaceutical sludge

    SciTech Connect

    Golla, P.S.; Johnson, H.W. ) Senthilnathan, P.R. )

    1992-02-01

    Application of electro acoustic principles for dewatering has been developed by Battelle Institute. The Department of Energy, Battelle Institute, and Ashbrook-Simon-Hartley, have jointly developed an Electro Acoustic Dewatering press (EAD press). The EAD press applies a combination of mechanical pressure, electrical current and ultrasonics. This press is utilized after conventional dewatering devices and can remove up to 50% water from filtered sludge cake at a fraction of the cost incurred in existing thermal drying devices. The dominant mechanism of sludge dewatering by EAD press is electro-osmosis due to the application of a direct current field. Electro-osmosis is caused by an electrical double layer of oppositely charged ions formed at the solid liquid interface, which is characterized by zeta potential. The ultrasonic fields help electro-osmosis by consolidation of the filter cake and by release of inaccessible liquid. The EAD press has been tested successfully on a variety of materials including apple pomace, corn gluten, sewage sludge, and coal fines. A three week long full scale trial was conducted successfully at a pharmaceutical industry to determine the application of this technology for dewatering waste activated sludge.

  4. Research and development needs in filtration and dewatering

    SciTech Connect

    Lockhart, N.C.; Kern, R.

    1996-10-01

    The first part of this paper deals with technology issues. These are categorized as (1) fundamental aspects, specifically suspension characteristics and dewatering mechanisms, along with process modelling and control; (2) pre-treatment procedures, both physical and chemical, that optimize the dewatering characteristics; (3) types of dewatering devices based on centrifuges, vacuum and pressure filters with particular reference to various combined field approaches using two or more complementary driving forces to achieve better performance. The second part of the paper (attributed principally to the first-named author) deals with related R and D issues, namely economic assessments and justification for particular R and D strategies, including benchmarking and operational factors that apply in industrial environments. Dewatering operations and R and D needs are also analyzed from the perspective of matching and integration into overall process flowsheets, and in the context of alternative processing or utilization strategies which avoid the dewatering step. The analysis concludes with a discussion on effective identification and utilization of existing knowledge, and the R and D management process. Although the paper draws heavily on experiences relating to the coal industry, much of the material is relevant to fine suspensions in general.

  5. Liquidization of dewatered organic sludge and anaerobic treatment

    SciTech Connect

    Sawayama, Shigeki; Inoue, Seiichi; Ogi, Tomoko

    1996-12-31

    Dewatered sewage sludge was thermochemically liquidized at 175 {degrees}C and the liquidized sludge was separated by centrifugation to 58% (w/w) supernatant and 42% precipitate. The amount of proteins in the liquidized sludge slightly decreased through the liquidization process, however, that of lipids increased. The supernatant separated from the sludge liquidized with dewatered sewage sludge was successfully anaerobically digested. Biogas yield from the supernatant from dewatered sewage sludge at organic loading concentrations of 1.9-2.2 g VS/l during 9 days incubation was 440 ml/g-added VS and digestion ratio was 66% (w/w). Biogas yield in the case of dewatered sewage sludge was 257 ml/g-added VS and digestion ratio was 45%. Similar results were obtained in the case of the anaerobically digested with sewage sludge and dewatered sludge. Anaerobic digestion of the supernatants from the liquidized sludges resulted in high biogas productivity and high digestion ratio compared with these of the original sludges. Moreover, the precipitates contained lower moisture, therefore, they can be incinerated easier than the respective original sludges.

  6. Dewatering of coalbed methane wells with hydraulic gas pump

    SciTech Connect

    Amani, M.; Juvkam-Wold, H.C.

    1995-12-31

    The coalbed methane industry has become an important source of natural gas production. Proper dewatering of coalbed methane (CBM) wells is the key to efficient gas production from these reservoirs. This paper presents the Hydraulic Gas Pump as a new alternative dewatering system for CBM wells. The Hydraulic Gas Pump (HGP) concept offers several operational advantages for CBM wells. Gas interference does not affect its operation. It resists solids damage by eliminating the lift mechanism and reducing the number of moving parts. The HGP has a flexible production rate and is suitable for all production phases of CBM wells. It can also be designed as a wireline retrievable system. We conclude that the Hydraulic Gas Pump is a suitable dewatering system for coalbed methane wells.

  7. Closed-loop operation with alternative dewatering technology

    SciTech Connect

    Halliday, W.S.; Bray, R.P.; Youens, J.W.

    1993-03-01

    The introduction of dewatering devices for closed-loop drilling-fluid circulating systems and reserve pits is derived from technology that has been used in the industrial- and sanitary-waste treatment industries for years. This paper describes an overview of the need for closed-loop systems and provides the optimum design layout, including the fit of a dewatering device, for a drilling location. The introduction of a nonconventional dewatering device, called a screw press/thickener, is reviewed. A case history describing use of this technology in a southern Louisiana inland-marsh-area well is analyzed for the technical and economic viability of operating in a closed-loop mode. Results from this effort include a viable alternative to hauling off waste fluids from drilling sites and the realization that use of this technology can be justified economically.

  8. Electrode kinetic and electro-kinetic effects in electroosmotic dewatering of clay suspensions

    SciTech Connect

    Vijh, A.K.

    1997-05-01

    Lockhart`s remarks on the author`s previous interpretation of the electrochemical aspects of the electroosmotic dewatering (EOD) of clay suspensions are analyzed to provide some further clarification. Based on Lockhart`s excellent work, the authors put forward here novel electrochemical interpretations of some features of the following experimental observations: (1) Galvani dewatering; (2) the dewatering efficiency; and (3) high voltage needed for dewatering Al-kaolinite and aluminum electrode effect.

  9. Simulation of Estuarine Flooding and Dewatering with Application to Great Bay, New Hampshire

    E-print Network

    Simulation of Estuarine Flooding and Dewatering with Application to Great Bay, New Hampshire Justin and dewatering of shallow estuaries is described and applications to hypothetical embayments and to the Great Bay transport implications are discussed. Keywords: Finite elements, estuarine flooding and dewatering

  10. Sludge dewatering: Sewage treatment. (Latest citations from the COMPENDEX database). Published Search

    SciTech Connect

    Not Available

    1993-05-01

    The bibliography contains citations concerning dewatering techniques and equipment for sewage treatment. Sewage sludge dewatering design, development, and evaluation are discussed. Essential types of dewatering equipment such as centrifuges, filters, presses, and drums are considered. (Contains 250 citations and includes a subject term index and title list.)

  11. Genesis of dewatering structures and its implications for melt-out till identification

    E-print Network

    Carlson, Anders

    Genesis of dewatering structures and its implications for melt-out till identification Anders E-mail: carlsand@geo.oregonstate.edu ABSTRACT. Dewatering structures are a common feature used to identify melt the conditions under which melt-out till can be deposited without forming dewatering structures, I use

  12. Evaluating Technologies for Reducing Nutrients in Dairy Effluent The Geotube Dewatering System

    E-print Network

    Mukhtar, Saqib

    Evaluating Technologies for Reducing Nutrients in Dairy Effluent The Geotube® Dewatering System in the North Bosque and Leon River Watersheds. In 2005, they evaluated the Geotube® de-watering system The Geotube® dewatering system was demonstrated by the Miratech Division of Ten Cate Nicolon and General

  13. Inferred pore pressures at the Costa Rica subduction zone: implications for dewatering processes

    E-print Network

    Fisher, Andrew

    Inferred pore pressures at the Costa Rica subduction zone: implications for dewatering processes a direct measure of the rate and magnitude of sediment dewatering. Laboratory consolidation tests indicate use a simple model of fluid flow to demonstrate that dewatering of the underthrust sediments can occur

  14. ADAPTIVE PRE-EMPTIVE CONTROL OF VACUUM DEWATERING IN PAPER MANUFACTURING 1

    E-print Network

    Li, Perry Y.

    ADAPTIVE PRE-EMPTIVE CONTROL OF VACUUM DEWATERING IN PAPER MANUFACTURING 1 Petar Bjegovic ¢¡ 3 by means of gravity, vacuum dewatering, mechanical pressing and thermal drying. This research proposes content, and the pressure settings in the vacuum dewatering section as actuators. The new topology has

  15. Effect of Processing Mode on Trace Elements in Dewatered Sludge Products Brian K. Richards1

    E-print Network

    Effect of Processing Mode on Trace Elements in Dewatered Sludge Products Brian K. Richards1 *, John compared. A single day's production of dewatered anaerobically-digested sludge (Syracuse, NY) was used essentially constant during dewatered sludge production with mean values (mg kg-1 total solids) of 5.6 Cd, 10

  16. REDD DEWATERING EFFECTS ON HATCHING AND LARVAL SURVIVAL OF THE ROBUST REDHORSE

    E-print Network

    Kwak, Thomas J.

    REDD DEWATERING EFFECTS ON HATCHING AND LARVAL SURVIVAL OF THE ROBUST REDHORSE J. M. FISK IIa , T habitats to spawn, but when power generation ceases, these areas are dewatered until the next pulse of water is released. We experimentally simulated the effects of dewatering periods on the survival

  17. Sludge dewatering: Sewage treatment. (Latest citations from the EI Compendex*plus database). Published Search

    SciTech Connect

    1996-01-01

    The bibliography contains citations concerning dewatering techniques and equipment for sewage treatment. Sewage sludge dewatering design, development, and evaluation are discussed. Essential types of dewatering equipment such as centrifuges, filters, presses, and drums are considered. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  18. Geotextile Tubes for the Sustainable Dewatering and Infrastructure (My Professional Journey)

    E-print Network

    Kamat, Vineet R.

    Geotextile Tubes for the Sustainable Dewatering and Infrastructure (My Professional Journey) Shobha K. Bhatia Syracuse University The need to dewater dredged sediments is a significant and urgent steps following the removal of sediments from water bodies is dewatering. Recently, geotextile tubes

  19. 1. VIEW LOOKING NORTH FROM DEWATERED CANAL; HEADGATES AND INTAKE ...

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

    1. VIEW LOOKING NORTH FROM DEWATERED CANAL; HEADGATES AND INTAKE CHANNEL AT LEFT; GUARDLOCK AT CENTER; SHEET PILING THROUGH SITE OF TOWPATH AT RIGHT - Dundee Canal, Headgates, Guardlock & Uppermost Section, 250 feet northeast of Randolph Avenue, opposite & in line with East Clifton Avenue, Clifton, Passaic County, NJ

  20. A parametric study of dewatering of fine coal

    SciTech Connect

    Sung, D.J.; Lee, K.J.; Parekh, B.K.

    1996-12-31

    A statistical design of parametric study of pressure filtration for fine coal dewatering is presented. The effects of five major process parameters of the dewatering, i.e. applied pressure, filtration time, cake thickness, solids concentration and slurry pH, on cake moisture reduction and air consumption were investigated. The study was conducted starting with two level factorial experiments to identify the most significant parameters in the filtration process, and concluding with response surface methodologies to establish an optimum operating condition for the dewatering of fine coal with these significant variables. An operating process condition for the dewatering that provided satisfactory performance was determined to be an applied pressure of 93 psi with a cake thickness of 2.5 cm and a filtration time of 4.8 minutes for this specific laboratory filtration system. At the optimum process condition the filter cake containing about 22 percent moisture by weight was obtained and the air was consumed by 4.1 m{sup 3}/(m{sup 2} min.kg). 6 refs., 4 figs., 2 tabs.

  1. 15. VIEW NORTHNORTHEAST OF TOW TANK No. 2, DEWATERED. ENCLOSED ...

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

    15. VIEW NORTH-NORTHEAST OF TOW TANK No. 2, DEWATERED. ENCLOSED AREAS AT BACK OF TUNNEL IS A HOUSING FOR CONDUCTING PERFORMANCE TESTING ON AIRCRAFT MODELS IN A VORTEX. - NASA Langley Research Center, Seaplane Towing Channel, 108 Andrews Street, Hampton, Hampton, VA

  2. 4. View northwest at the southeast facade of the dewatered ...

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

    4. View northwest at the southeast facade of the dewatered culvert inlet headwall. Part of canal bank has been removed above the headwall. - Delaware & Raritan Canal, Ten Mile Run Culvert, 1.5 miles South of Blackwells Road, East Millstone, Somerset County, NJ

  3. 28. VIEW NORTH TOWARD DERBY DURING DEWATERING. DAM IN CENTER ...

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

    28. VIEW NORTH TOWARD DERBY DURING DEWATERING. DAM IN CENTER OF PICTURE WITH SHELTON GATEHOUSE ON LEFT AND DERBY GATEHOUSE ON RIGHT. - Ousatonic Water Power Company, Dam & Canals, CT Routes 34 & 108, 1 mile North of Derby-Shelton Bridge, Derby, New Haven County, CT

  4. 30. VIEW SOUTHEAST ON SHELTON SIDE OF DAM DURING DEWATERING. ...

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

    30. VIEW SOUTHEAST ON SHELTON SIDE OF DAM DURING DEWATERING. CORNER OF SHELTON LOCKS AND MITRE GATES AT RIGHT. - Ousatonic Water Power Company, Dam & Canals, CT Routes 34 & 108, 1 mile North of Derby-Shelton Bridge, Derby, New Haven County, CT

  5. 1. View southeast at northwest facade of dewatered culvert outlet ...

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

    1. View southeast at northwest facade of dewatered culvert outlet headwall, above which part of the canal bank has been removed. Buttresses and upper portion of headwall (above arches) are nineteenth-century additions to the lower, original headwall. - Delaware & Raritan Canal, Ten Mile Run Culvert, 1.5 miles South of Blackwells Road, East Millstone, Somerset County, NJ

  6. Groundwater Sustainability through a Novel Dewatering Technology

    NASA Astrophysics Data System (ADS)

    Jin, Y.; Holzbecher, E.; Ebneth, S.

    2012-12-01

    Groundwater plays a key role in the hydrologic cycle and ecosystem balances. Over the past decades, groundwater is intensively extracted in order to keep construction or mining sites dry. For the latter purpose the pumped water is usually discharged into a nearby surface water body or injected into an aquifer distant from the abstraction sites. As a result, aquifers are depleted and the local eco-system is disrupted as a consequence of falling groundwater tables. Given ongoing pressure on aquifer from abstraction sites, it is vital to bring up adequate attention on groundwater conservation. We demonstrate a novel technique, Düsensauginfiltration (DSI, translated as 'nozzel-suction-infiltration'), which avoids water conveyance but still lowers the groundwater table locally. The method combines abstraction of groundwater at the upper part of the aquifer with injection in the same borehole, but at a greater depth. Hence no water is withdrawn from the system. The method is already used practically in Germany, Netherlands, and China, however, it is not yet fully scientifically understood and evaluated. Currently, two tests sites in Germany, for single and multi well respectively, are selected, at which the DSI technology is currently examined. The project is cooperated with a leading dewatering company (Hoelscher Wasserbau GmbH) and funded by Deutsche Bundesstiftung Umwelt (DBU). To provide the basic principle of the method, we present numerical models solving the differential equation, which is derived from Darcy's Law and mass conservation, describing groundwater flow. We set up stationary numerical models in 2D (vertical cross section for single well case) and 3D (multi well case and/or when ambient groundwater flow is considered) using COMSOL Multiphysics. Since our model region only involves the saturated part of the unconfined aquifer, the numerical model solves a free boundary problem using hydraulic pressure as unknown variable. Two physical modes are included in the model setting. In Darcy's Law mode, we consider the changing groundwater table as free upper boundary and the impervious bottom as lower boundary. In the 2D model, the pumping and injection are specified via mass flux condition at the inner boundary, while zero hydraulic pressure is used at outer boundary for pressure constraints. Ambient groundwater flow can be considered in the 3D model using corresponding conditions at the outer model boundaries, while pumping and injection are prescribed along the borehole surfaces. A moving mesh is applied using arbitrary Lagrangian-Eulerian (ALE) method by which the location of free boundary is determined as a result. Within our simulation, the two physics modes, Darcy's Law and ALE, are coupled simultaneously. Aquifer parameters, such as hydraulic conductivity and anisotropy, are studied for sensitivity analysis. Results indicate that the method is promising especially for conductive aquifers consisting of sand and gravels. However, the short cut flow in the direct vicinity of borehole should not be ignored. For the homogenous isotropic aquifer, and equal pumping and injection rates, the DSI method yields approximately half the drawdown of the conventional approach of pumping alone. As one of the main influencing parameters, the anisotropy factor plays an important role. A decreasing anisotropy factor corresponds with deeper and wider drawdown.

  7. Development of an Advanced Fine Coal Suspension Dewatering Process

    SciTech Connect

    B. K. Parekh; D. P. Patil

    2008-04-30

    With the advancement in fine coal cleaning technology, recovery of fine coal (minus 28 mesh) has become an attractive route for the U.S. coal industry. The clean coal recovered using the advanced flotation technology i.e. column flotation, contains on average 20% solids and 80% water, with an average particle size of 35 microns. Fine coal slurry is usually dewatered using a vacuum dewatering technique, providing a material with about 25 to 30 percent moisture. The process developed in this project will improve dewatering of fine (0.6mm) coal slurry to less than 20 percent moisture. Thus, thermal drying of dewatered wet coal will be eliminated. This will provide significant energy savings for the coal industry along with some environmental benefits. A 1% increase in recovery of coal and producing a filter cake material of less than 20 % moisture will amount to energy savings of 1900 trillion Btu/yr/unit. In terms of the amount of coal it will be about 0.8% of the total coal being used in the USA for electric power generation. It is difficult to dewater the fine clean coal slurry to about 20% moisture level using the conventional dewatering techniques. The finer the particle, the larger the surface area and thus, it retains large amounts of moisture on the surface. The coal industry has shown some reluctance in using the advanced coal recovery techniques, because of unavailability of an economical dewatering technique which can provide a product containing less than 20% moisture. The U.S.DOE and Industry has identified the dewatering of coal fines as a high priority problem. The goal of the proposed program is to develop and evaluate a novel two stage dewatering process developed at the University of Kentucky, which involves utilization of two forces, namely, vacuum and pressure for dewatering of fine coal slurries. It has been observed that a fine coal filter cake formed under vacuum has a porous structure with water trapped in the capillaries. When this porous cake is subjected to pressure for a short time, the free water present is released from the filter cake. Laboratory studies have shown that depending on the coal type a filter cake containing about 15% moisture could be obtained using the two-stage filtration technique. It was also noted that applying intermittent breaks in vacuum force during cake formation, which disturbed the cake structure, helped in removing moisture from the filter cakes. In this project a novel approach of cleaning coal using column flotation was also developed. With this approach the feed capacity of the column is increased significantly, and the column was also able to recover coarser size coal which usually gets lost in the process. The outcome of the research benefits the coal industry, utility industry, and indirectly the general public. The benefits can be counted in terms of clean energy, cleaner environment, and lower cost power.

  8. Impact of dewatering technologies on specific methanogenic activity.

    PubMed

    Batstone, Damien J; Lu, Yang; Jensen, Paul D

    2015-10-01

    Dewatering methods for recuperative thickening and final dewatering can potentially impact methanogenic activity and microbial community. This influences both the feasibility of recuperative thickening to increase solids residence time within a digester, and the utilisation of dewatered digestate as inoculum for new digesters. Thickening technology can reduce methanogenic activity through either air contact (rotary drum, DAF, or belt filter press), or by lysing cells through shear (centrifuge). To assess this, two plants with recuperative thickening (rotary drum) in their anaerobic digester, and five without recuperative thickening, had specific methanogenic activity tested in all related streams, including dewatering feed, thickened return, final cake, and centrate. All plants had high speed centrifuges for final dewatering. The digester microbial community was also assessed through 16s pyrotag sequencing and subsequent principal component analysis (PCA). The specific methanogenic activity of all samples was in the expected range of 0.2-0.4 gCOD gVS(-1)d(-1). Plants with recuperative thickening did not have lower digester activity. Centrifuge based dewatering had a significant and variable impact on methanogenic activity in all samples, ranging between 20% and 90% decrease but averaging 54%. Rotary drum based recuperative thickening had a far smaller impact on activity, with a 0% per-pass drop in activity in one plant, and a 20% drop in another. However, the presence of recuperative thickening was a major predictor of overall microbial community (PC1, p = 0.0024). Microbial community PC3 (mainly driven by a shift in methanogens) was a strong predictor for sensitivity in activity to shear (p = 0.0005, p = 0.00001 without outlier). The one outlier was related to a plant producing the wettest cake (17% solids). This indicates that high solids is a potential driver of sensitivity to shear, but that a resilient microbial community can also bestow resilience. Sensitivity of methanogens to centrifuging does not rule out centrifuges for recuperative thickening (particularly where hydrolysis is rate-limiting), but may impose a maximum return rate to avoid digester failure. PMID:26304593

  9. Evaluation of Dewatering Performance and Fractal Characteristics of Alum Sludge

    PubMed Central

    Sun, Yongjun; Fan, Wei; Zheng, Huaili; Zhang, Yuxin; Li, Fengting; Chen, Wei

    2015-01-01

    The dewatering performance and fractal characteristics of alum sludge from a drinking-water treatment plant were investigated in this study. Variations in residual turbidity of supernatant, dry solid content (DS), specific resistance to filtration (SRF), floc size, fractal dimension, and zeta potential were analyzed. Sludge dewatering efficiency was evaluated by measuring both DS and SRF. Results showed that the optimum sludge dewatering efficiency was achieved at 16 mg?L-1 flocculant dosage and pH 7. Under these conditions, the maximum DS was 54.6%, and the minimum SRF was 0.61 × 1010 m?kg-1. Floc-size measurements demonstrated that high flocculant dosage significantly improved floc size. Correlation analysis further revealed a strong correlation between fractal dimension and floc size after flocculation. A strong correlation also existed between floc size and zeta potential, and flocculants with a higher cationic degree had a larger correlation coefficient between floc size and zeta potential. In the flocculation process, the main flocculation mechanisms involved adsorption bridging under an acidic condition, and a combination between charge neutralization and adsorption-bridging interaction under neutral and alkaline conditions. PMID:26121132

  10. Evaluation of Dewatering Performance and Fractal Characteristics of Alum Sludge.

    PubMed

    Sun, Yongjun; Fan, Wei; Zheng, Huaili; Zhang, Yuxin; Li, Fengting; Chen, Wei

    2015-01-01

    The dewatering performance and fractal characteristics of alum sludge from a drinking-water treatment plant were investigated in this study. Variations in residual turbidity of supernatant, dry solid content (DS), specific resistance to filtration (SRF), floc size, fractal dimension, and zeta potential were analyzed. Sludge dewatering efficiency was evaluated by measuring both DS and SRF. Results showed that the optimum sludge dewatering efficiency was achieved at 16 mg?L(-1) flocculant dosage and pH 7. Under these conditions, the maximum DS was 54.6%, and the minimum SRF was 0.61 × 10(10) m?kg(-1). Floc-size measurements demonstrated that high flocculant dosage significantly improved floc size. Correlation analysis further revealed a strong correlation between fractal dimension and floc size after flocculation. A strong correlation also existed between floc size and zeta potential, and flocculants with a higher cationic degree had a larger correlation coefficient between floc size and zeta potential. In the flocculation process, the main flocculation mechanisms involved adsorption bridging under an acidic condition, and a combination between charge neutralization and adsorption-bridging interaction under neutral and alkaline conditions. PMID:26121132

  11. Evaluation of hyperbaric filtration for fine coal dewatering. Final report

    SciTech Connect

    Parekh, B.K.; Hogg, R.; Fonseca, A.

    1996-08-15

    The main objectives of the project were to investigate the fundamental aspects of particle-liquid interaction in fine coal dewatering, to conduct laboratory and pilot plant studies on the applicability of hyperbaric filter systems and to develop process conditions for dewatering of fine clean coal to less than 20% moisture. The program consisted of three phases, namely Phase 1 -- Model Development, Phase 2 -- Laboratory Studies, Phase 3 -- Pilot Plant Testing. The Pennsylvania State University led efforts in Phase 1, the University of Kentucky in Phase 2, and CONSOL Inc. in Phase 3 of the program. All three organizations were involved in all the three phases of the program. The Pennsylvania State University developed a theoretical model for hyperbaric filtration systems, whereas the University of Kentucky conducted experimental studies to investigate fundamental aspects of particle-liquid interaction and application of high pressure filter in fine coal dewatering. The optimum filtration conditions identified in Phase 1 and 2 were tested in two of the CONSOL Inc. coal preparation plants using an Andritz Ruthner portable hyperbaric filtration unit.

  12. Environmental effects of dredging. Current district dredged material dewatering practices. Technical notes

    SciTech Connect

    1988-04-01

    This technical note summarizes the current US Army Corps of Engineers state of practice in dewatering dredged material. State-of-practice dewatering methods are currently in full-scale use by one or more Corps of Engineers District Offices as contrasted with state-of-the-art methods, which may not have been demonstrated in full-scale applications. The Corps of Engineers conducted research to investigate state-of-the-art dredged material dewatering techniques under the Dredged Material Research Program (DMRP). Based on DMRP research, a number of dewatering methods have been recommended for implementation. The purpose of this note is to describe which of the dewatering practices recommended by DMRP research have been implemented and to determine whether these practices work as well in full-scale applications as was envisioned based on research studies. Also, innovative dewatering techniques developed or applied by the Districts is documented to encourage further investigation and possible use.

  13. Dewatering: Coal and mineral processing. (Latest citations from the COMPENDEX database). Published Search

    SciTech Connect

    Not Available

    1993-05-01

    The bibliography contains citations concerning the technology of dewatering. Included is coverage of techniques, processes, and evaluations applied to coal processing, coal slurry preparation, ash treatments, and processing of other mineral ores. Mechanical devices, heating devices, filtering techniques, air drying, the use of surfactants and flocculants, and design techniques in dewatering systems are discussed. Dewatering of peats, sewage sludges, and industrial sludges are referenced in related bibliographies. (Contains 250 citations and includes a subject term index and title list.)

  14. Application of water-soluble polymer in dewatering of fine coal

    SciTech Connect

    Xingyong, W.

    1999-07-01

    The addition of water-soluble polymer to fine coal slurry to enhance dewatering process of fine coal is considered to be one of the most effective ways of solving the problems of dewatering of fine coal. A series of tests are conducted with a vacuum dewatering apparatus to study the effects of various factors such as the species of polymer, polymer dosage and its ways of addition, and the pH of fine coal slurry on filtrating and dewatering of fine coal.

  15. Dewatering studies of fine clean coal. Annual technical report, September 1, 1990--August 31, 1991

    SciTech Connect

    Parekh, B.K.

    1991-12-31

    The main objective of the present research program is to study and understand dewatering characteristics of ultrafine clean coal obtained using the advanced column flotation technique from the Kerr-McGee`s Galatia preparation plant fine coal waste stream. It is also the objective of the research program to utilize the basic study results, i.e., surface chemical, particle shape particle size distribution, etc., in developing a cost-effective dewatering method. The ultimate objective is to develop process criteria to obtain a dewatered clean coal product containing less that 20 percent moisture, using the conventional vacuum dewatering equipment. (VC)

  16. The effect of coal bed dewatering and partial oxidation on biogenic methane potential

    USGS Publications Warehouse

    Jones, Elizabeth J.P.; Harris, Steve H.; Barnhart, Elliott P.; Orem, William H.; Clark, Arthur C.; Corum, Margo D.; Kirshtein, Julie D.; Varonka, Matthew S.; Voytek, Mary A.

    2013-01-01

    Coal formation dewatering at a site in the Powder River Basin was associated with enhanced potential for secondary biogenic methane determined by using a bioassay. We hypothesized that dewatering can stimulate microbial activity and increase the bioavailability of coal. We analyzed one dewatered and two water-saturated coals to examine possible ways in which dewatering influences coal bed natural gas biogenesis by looking at differences with respect to the native coal microbial community, coal-methane organic intermediates, and residual coal oxidation potential. Microbial biomass did not increase in response to dewatering. Small Subunit rRNA sequences retrieved from all coals sampled represented members from genera known to be aerobic, anaerobic and facultatively anaerobic. A Bray Curtis similarity analysis indicated that the microbial communities in water-saturated coals were more similar to each other than to the dewatered coal, suggesting an effect of dewatering. There was a higher incidence of long chain and volatile fatty acid intermediates in incubations of the dewatered coal compared to the water-saturated coals, and this could either be due to differences in microbial enzymatic activities or to chemical oxidation of the coal associated with O2 exposure. Dilute H2O2 treatment of two fractions of structural coal (kerogen and bitumen + kerogen) was used as a proxy for chemical oxidation by O2. The dewatered coal had a low residual oxidation potential compared to the water-saturated coals. Oxidation with 5% H2O2 did increase the bioavailability of structural coal, and the increase in residual oxidation potential in the water saturated coals was approximately equivalent to the higher methanogenic potential measured in the dewatered coal. Evidence from this study supports the idea that coal bed dewatering could stimulate biogenic methanogenesis through partial oxidation of the structural organics in coal once anaerobic conditions are restored.

  17. Electrical field: a historical review of its application and contributions in wastewater sludge dewatering.

    PubMed

    Mahmoud, Akrama; Olivier, Jérémy; Vaxelaire, Jean; Hoadley, Andrew F A

    2010-04-01

    Electric field-assisted dewatering, also called electro-dewatering, is a technology in which a conventional dewatering mechanism such a pressure dewatering is combined with electrokinetic effects to realize an improved liquid/solids separation, to increase the final dry solids content and to accelerate the dewatering process with low energy consumption compared to thermal drying. Electro-dewatering is not a new idea, but the practical industrial applications have been limited to niche areas in soil mechanics, civil engineering, and the ceramics industry. Recently, it has received great attention, specially, in the fields of fine-particle sludge, gelatinous sludge, sewage sludge, pharmaceutical industries, food waste and bull kelp, which could not be successfully dewatered with conventional mechanical methods. This review focuses on the scientific and practical aspects of the application of an electrical field in laboratory/industrial dewatering, and discusses this in relation to conventional dewatering techniques. A comprehensive bibliography of research in the electro-dewatering of wastewater sludges is included. As the fine-particle suspensions possess a surface charge, usually negative, they are surrounded by a layer with a higher density of positive charges, the electric double layer. When an electric field is applied, the usually negative charged particles move towards the electrode of the opposite charge. The water, commonly with cations, is driven towards the negative electrode. Electro-dewatering thus involves the well-known phenomena of electrophoresis, electro-osmosis, and electromigration. Following a detailed outline of the role of the electric double layer and electrokinetic phenomena, an analysis of the components of applied voltage and their significance is presented from an electrochemical viewpoint. The aim of this elementary analysis is to provide a fundamental understanding of the different process variables and configurations in order to identify potential improvements. Also discussed herein is the investigation of the electrical behaviour of a porous medium, with particular emphasis on porous medium conductivity determination. PMID:20303137

  18. Modeling of hyperbaric filtration and dewatering of coal

    NASA Astrophysics Data System (ADS)

    Ranjan, Sushil

    Generalized models have been developed for continuous hyperbaric filtration to evaluate cake formation, filter capacity/filter area, cake dewatering, air consumption and residual cake saturation/residual cake moisture. Emphasis has been placed on cake structure as being a major controlling factor in fine coal dewatering by filtration. The effects of cake structure, as defined by the distributions of pore size and shape, have been reviewed. A simple model relating cake structure to feed particle characteristics is presented and applied to a practical case of fine coal dewatering. A binary packing model has been proposed to explain the existence of compressibility in non-compressible cakes. This model proposes an inner open-structure in the main cake, with the inner layer being compressible. The variation in the inner cake porosity with applied pressure has been used to explain the change in specific cake resistance and filter capacity (solids cake throughput). Process simulations have been conducted for a single stage and a two stage process, wherein the original feed has been split into a coarse fraction and a fine fraction (and then each fraction processed separately). The process simulations for a two stage process show a lot of promise as this leads to a lowering of the required filter area and the residual cake moisture. The required filter area increases, while the residual cake moisture decreases as the cut size for the two stage process is increased. However, the advantages of a two stage process are adversely affected by an inefficient separation process, which leads to an increased filter area and a higher residual cake moisture and the two stage process approaches a single stage process.

  19. OVERVIEW OF REMAINS OF DEWATERING BUILDING, LOOKING SOUTH TOWARD CYANIDE ...

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

    OVERVIEW OF REMAINS OF DEWATERING BUILDING, LOOKING SOUTH TOWARD CYANIDE PROCESSING AREA. WATER USED IN PROCESSING AT THE STAMP MILL WAS CIRCULATED HERE FOR RECLAMATION. SANDS WERE SETTLED OUT AND DEPOSITED IN ONE OF TWO TAILINGS HOLDING AREAS. CLEARED WATER WAS PUMPED BACK TO THE MILL FOR REUSE. THIS PROCESS WAS ACCOMPLISHED BY THE USE OF SETTLING CONES, EIGHT FEET IN DIAMETER AND SIX FEET HIGH. THE REMAINS OF FOUR CONES ARE AT CENTER, BEHIND THE TANK IN THE FOREGROUND. TO THE LEFT IS THE MAIN ACCESS ROAD BETWEEN THE MILL AND THE PARKING LOT. - Keane Wonder Mine, Park Route 4 (Daylight Pass Cutoff), Death Valley Junction, Inyo County, CA

  20. New coal dewatering technology turns sludge to powder

    SciTech Connect

    2009-03-15

    Virginian Tech's College of Engineering's Roe-Hoan Yoon and his group have developed a hyperbaric centrifuge that can dewater coal as fine as talcum powder. Such coal fines presently must be discarded by even the most advanced coal cleaning plants because of their high moisture content. The new technology can be used with the Microcel technology to remove ash, to re-mine the fine coal discarded to impoundments and to help minimize waste generation. Virginia Tech has received $1 million in funding from the US Department of State to also help the Indian coal industry produce a cleaner product. 1 photo.

  1. Redd dewatering effects on hatching and larval survival of the robust redhorse

    USGS Publications Warehouse

    Fisk, J. M., III; Kwak, Thomas J.; Heise, R. J.; Sessions, F. W.

    2013-01-01

    Riverine habitats have been altered and fragmented from hydroelectric dams and change spatially and temporally with hydropower flow releases. Hydropeaking flow regimes for electrical power production inundate areas that create temporary suitable habitat for fish that may be rapidly drained. Robust redhorse Moxostoma robustum, an imperiled, rare fish species, uses such temporary habitats to spawn, but when power generation ceases, these areas are dewatered until the next pulse of water is released. We experimentally simulated the effects of dewatering periods on the survival of robust redhorse eggs and larvae in the laboratory. Robust redhorse eggs were placed in gravel in eyeing-hatching jars (three jars per treatment) and subjected to one of four dewatering periods (6, 12, 24 and 48 h), followed by 12 h of inundation for each treatment, and a control treatment was never dewatered. Egg desiccation was observed in some eggs in the 24- and 48-h treatments after one dewatering period. For all treatments except the control, the subsequent dewatering period after eggs hatched was lethal. Larval emergence for the control treatment was observed on day 5 post-hatching and continued until the end of the experiment (day 21). Larval survival was significantly different between the control and all dewatering treatments for individuals in the gravel. These findings support the need for hydropower facilities to set minimum flows to maintain inundation of spawning areas for robust redhorse and other species to reduce dewatering mortality.

  2. 46 CFR 28.255 - Bilge pumps, bilge piping, and dewatering systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... prevention requirements of 33 CFR parts 151 and 155. ... 46 Shipping 1 2011-10-01 2011-10-01 false Bilge pumps, bilge piping, and dewatering systems. 28... the Aleutian Trade § 28.255 Bilge pumps, bilge piping, and dewatering systems. (a) Each vessel must...

  3. EVALUATION OF FULL-SCALE SUGAR BEET TRANSPORT WATER SOLIDS DEWATERING SYSTEM

    EPA Science Inventory

    The objectives of this study were to evaluate a full-scale vacuum filtration system for dewatering solids removed from the transport water in an operating beet sugar plant in terms of operational reliability and efficiency, economics, and ultimate disposal of the dewatered solids...

  4. EVALUATION OF DEWATERING DEVICES FOR PRODUCING HIGH-SOLIDS SLUDGE CAKE

    EPA Science Inventory

    Pilot-plant dewatering tests were made to establish design and operating parameters for dewatering municipal wastewater sludges on recessed plate filter presses (both diaphragm and fixed volume types), continuous belt presses, and retrofit units for a vacuum filter. Results from ...

  5. Sludge dewatering: Sewage and industrial wastes. (Latest citations from Pollution Abstracts database). Published Search

    SciTech Connect

    Not Available

    1993-11-01

    The bibliography contains citations concerning techniques and equipment used in dewatering waste products. Included are techniques for sewage waste as well as industrial, mining, petroleum, and municipal waste sludge. Dewatering processes, device design, and performance evaluations are considered. (Contains 250 citations and includes a subject term index and title list.)

  6. 46 CFR 28.255 - Bilge pumps, bilge piping, and dewatering systems.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... prevention requirements of 33 CFR parts 151 and 155. ... 46 Shipping 1 2014-10-01 2014-10-01 false Bilge pumps, bilge piping, and dewatering systems. 28... the Aleutian Trade § 28.255 Bilge pumps, bilge piping, and dewatering systems. (a) Each vessel must...

  7. EVALUATION OF SOLIDS DEWATERING FOR A PILOT-SCALE THIOSORBIC LIME SO2 SCRUBBER

    EPA Science Inventory

    The paper gives results of an evaluation of solids dewatering for a pilot-scale thiosorbic lime SO2 scrubber. Pilot plant data showed that the dissolved magnesium in thiosorbic lime caused deterioration of solids dewatering properties. The slurry settling rate increased when the ...

  8. Sludge dewatering: Sewage and industrial wastes. (Latest citations from pollution abstracts). Published Search

    SciTech Connect

    1995-11-01

    The bibliography contains citations concerning sewage sludge dewatering techniques and equipment in industrial and municipal waste treatment systems. Topics include dewatering processes and control, activated sludge systems, fluidized bed systems, biological treatment, heavy metal recovery, and economic aspects. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  9. An experimental investigation of microalgal dewatering efficiency of a belt filter system

    E-print Network

    Sandip, Anjali

    2014-05-31

    is preferred over other dewatering technologies as it has lower energy consumption. However, a microalgal feed concentration of 10 - 40 g dry wt. /L is required prior to dewatering on a belt filter system. The objective of this study was to investigate...

  10. 46 CFR 28.255 - Bilge pumps, bilge piping, and dewatering systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... prevention requirements of 33 CFR parts 151 and 155. ... 46 Shipping 1 2010-10-01 2010-10-01 false Bilge pumps, bilge piping, and dewatering systems. 28... the Aleutian Trade § 28.255 Bilge pumps, bilge piping, and dewatering systems. (a) Each vessel must...

  11. 46 CFR 28.255 - Bilge pumps, bilge piping, and dewatering systems.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... prevention requirements of 33 CFR parts 151 and 155. ... 46 Shipping 1 2013-10-01 2013-10-01 false Bilge pumps, bilge piping, and dewatering systems. 28... the Aleutian Trade § 28.255 Bilge pumps, bilge piping, and dewatering systems. (a) Each vessel must...

  12. Sludge dewatering: Sewage and industrial wastes. (Latest citations from Pollution Abstracts). Published Search

    SciTech Connect

    Not Available

    1993-07-01

    The bibliography contains citations concerning techniques and equipment used in dewatering waste products. Included are techniques for sewage waste as well as industrial, mining, petroleum, and municipal waste sludge. Dewatering processes, device design, and performance evaluations are considered. (Contains 250 citations and includes a subject term index and title list.)

  13. 46 CFR 28.255 - Bilge pumps, bilge piping, and dewatering systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... prevention requirements of 33 CFR parts 151 and 155. ... 46 Shipping 1 2012-10-01 2012-10-01 false Bilge pumps, bilge piping, and dewatering systems. 28... the Aleutian Trade § 28.255 Bilge pumps, bilge piping, and dewatering systems. (a) Each vessel must...

  14. Sludge dewatering: Sewage and industrial wastes. (Latest citations from Pollution Abstracts). Published Search

    SciTech Connect

    Not Available

    1992-06-01

    The bibliography contains citations concerning techniques and equipment used in dewatering waste products. Included are techniques for sewage waste as well as industrial, mining, petroleum, and municipal waste sludge. Dewatering processes, device design, and performance evaluations are considered. (Contains 250 citations and includes a subject term index and title list.)

  15. DEWATERING ACTIVE UNDERGROUND COAL MINES. TECHNICAL ASPECTS AND COST-EFFECTIVENESS

    EPA Science Inventory

    This study evaluated the cost-effectiveness of dewatering an active underground coal mine as an alternative or supplement to treating acid mine drainage. A dewatering program was formulated and base-line data collection was performed in conjunction with exploration of hydrogeolog...

  16. Phosphorus partitioning in co-dewatering biosolids and water treatment residuals.

    PubMed

    Elliott, Herschel A; Taylor, Malcolm

    2014-01-01

    Stabilization and dewatering methods for wastewater solids determine the concentration and nature of phosphorus (P) in biosolids and in-plant sidestreams recycled to the liquid treatment facility. Because water treatment residuals (WTR) exhibit strong immobilization of soluble P, this study evaluated the impact of co-dewatering WTR and biosolids on the P partitioning during dewatering and the environmental lability of biosolids-P measured by water-extractable P (WEP). Overall, P progressively partitioned into the water-insoluble particulate-bound form in dewatered cake with increasing blending ratio (BR) - defined as the dry mass ratio of WTR to biosolids. The reject water total P (TP) content from dewatering biosolids alone (250 mg L?¹) was reduced to 60 mg L?¹ for a BR = 1.5. Polymer addition resulted in statistically (? = 0.05) lower reject liquid TP, suggesting the cationic polyelectrolyte contributed to P binding. The WEP of the dewatered cake (?20% solids) dropped from 2.36 g kg?¹ (biosolids only) to ?0.14 g kg?¹ for BR = 1.5, meaning the P in land-applied co-processed cake is less susceptible to solubilization by surface runoff compared to unamended biosolids. Co-dewatering can reduce P in return flows and fix P in the dewatered solids in a form less prone to off-site migration following land application. PMID:25098870

  17. Development of an Ultra-fine Coal Dewatering Technology and an Integrated Flotation-Dewatering System for Coal Preparation Plants

    SciTech Connect

    Wu Zhang; David Yang; Amar Amarnath; Iftikhar Huq; Scott O'Brien; Jim Williams

    2006-12-22

    The project proposal was approved for only the phase I period. The goal for this Phase I project was to develop an industrial model that can perform continuous and efficient dewatering of fine coal slurries of the previous flotation process to fine coal cake of {approx}15% water content from 50-70%. The feasibility of this model should be demonstrated experimentally using a lab scale setup. The Phase I project was originally for one year, from May 2005 to May 2006. With DOE approval, the project was extended to Dec. 2006 without additional cost from DOE to accomplish the work. Water has been used in mining for a number of purposes such as a carrier, washing liquid, dust-catching media, fire-retardation media, temperature-control media, and solvent. When coal is cleaned in wet-processing circuits, waste streams containing water, fine coal, and noncombustible particles (ash-forming minerals) are produced. In many coal preparation plants, the fine waste stream is fed into a series of selection processes where fine coal particles are recovered from the mixture to form diluted coal fine slurries. A dewatering process is then needed to reduce the water content to about 15%-20% so that the product is marketable. However, in the dewatering process currently used in coal preparation plants, coal fines smaller than 45 micrometers are lost, and in many other plants, coal fines up to 100 micrometers are also wasted. These not-recovered coal fines are mixed with water and mineral particles of the similar particle size range and discharged to impoundment. The wasted water from coal preparation plants containing unrecoverable coal fine and mineral particles are called tailings. With time the amount of wastewater accumulates occupying vast land space while it appears as threat to the environment. This project developed a special extruder and demonstrated its application in solid-liquid separation of coal slurry, tailings containing coal fines mostly less than 50 micron. The extruder is special because all of its auger surface and the internal barrier surface are covered with the membranes allowing water to drain and solid particles retained. It is believed that there are four mechanisms working together in the dewatering process. They are hydrophilic diffusion flow, pressure flow, agitation and air purging. Hydrophilic diffusion flow is effective with hydrophilic membrane. Pressure flow is due to the difference of hydraulic pressure between the two sides of the membrane. Agitation is provided by the rotation of the auger. Purging is achieved with the air blow from the near bottom of the extruder, which is in vertical direction.

  18. Comprehensive experimental study on prevention of land subsidence caused by dewatering in deep foundation pit with hanging waterproof curtain

    NASA Astrophysics Data System (ADS)

    Yang, T. L.; Yan, X. X.; Wang, H. M.; Huang, X. L.; Zhan, G. H.

    2015-11-01

    Land subsidence caused by dewatering of deep foundations pit has currently become the focus of prevention and control of land subsidence in Shanghai. Because of the reliance on deep foundation dewatering pit projects, two comprehensive test sites were established to help prevent land subsidence. Through geological environmental monitoring during dewatering of a deep foundation pit, the analysis of the relation between artesian water level and soil subsidence, some basic features of land subsidence caused by dewatering of deep foundation pits are elucidated. The results provide a scientific basis for prevention and control of land subsidence caused by dewatering in deep foundation pits.

  19. POC-scale testing of an advanced fine coal dewatering equipment/technique

    SciTech Connect

    Groppo, J.G.; Parekh, B.K.; Rawls, P.

    1995-11-01

    Froth flotation technique is an effective and efficient process for recovering of ultra-fine (minus 74 {mu}m) clean coal. Economical dewatering of an ultra-fine clean coal product to a 20 percent level moisture will be an important step in successful implementation of the advanced cleaning processes. This project is a step in the Department of Energy`s program to show that ultra-clean coal could be effectively dewatered to 20 percent or lower moisture using either conventional or advanced dewatering techniques. As the contract title suggests, the main focus of the program is on proof-of-concept testing of a dewatering technique for a fine clean coal product. The coal industry is reluctant to use the advanced fine coal recovery technology due to the non-availability of an economical dewatering process. in fact, in a recent survey conducted by U.S. DOE and Battelle, dewatering of fine clean coal was identified as the number one priority for the coal industry. This project will attempt to demonstrate an efficient and economic fine clean coal slurry dewatering process.

  20. Classification and Disposal of Dewatered Sediments Terri Blackmar, P.E. (terri.blackmar@tetratech.com) (Tetra Tech, Inc., Green Bay, WI)

    E-print Network

    Classification and Disposal of Dewatered Sediments Terri Blackmar, P.E. (terri-Urbana) ABSTRACT: Two of the major costs in sediment remediation projects are dewatering and disposal of the dredged sediment. When evaluating dewatering methods, the shear strength of the dewatered sediment must

  1. POC-Scale Testing of an Advanced Fine Coal Dewatering Equipment/Technique

    SciTech Connect

    B. K. Karekh; D. Tao; J. G. Groppo

    1998-08-28

    Froth flotation technique is an effective and efficient process for recovering of ultra-fine (minus 74 mm) clean coal. Economical dewatering of an ultra-fine clean coal product to a 20% level moisture will be an important step in successful implementation of the advanced cleaning processes. This project is a step in the Department of Energy's program to show that ultra-clean coal could be effectively dewatered to 20% or lower moisture using either conventional or advanced dewatering techniques. The cost-sharing contract effort is for 45 months beginning September 30, 1994. This report discusses technical progress made during the quarter from January 1 ? March 31, 1998.

  2. Integrated treatment of municipal sewage sludge by deep dewatering and anaerobic fermentation for biohydrogen production.

    PubMed

    Yu, Li; Yu, Yang; Jiang, Wentian; Wei, Huangzhao; Sun, Chenglin

    2015-02-01

    The increasing sludge generated in wastewater treatment plants poses a threat to the environment. Based on the traditional processes, sludge dewatered by usual methods was further dewatered by hydraulic compression and the filtrate released was treated by anaerobic fermentation. The difficulties in sludge dewatering were associated with the existence of sludge flocs or colloidal materials. A suitable CaO dosage of 125 mg/g dry sludge (DS) could further decrease the moisture content of sludge from 82.4 to 50.9 %. The filtrate from the dewatering procedure was a potential substrate for biohydrogen production. Adding zero-valent iron (ZVI) into the anaerobic system improved the biohydrogen yield by 20 %, and the COD removal rate was lifted by 10 % as well. Meanwhile, the sludge morphology and microbial community were altered. The novel method could greatly reduce the sludge volume and successfully treated filtrate along with the conversion of organics into biohydrogen. PMID:25192669

  3. Effect of brief navigation-related dewaterings on fish eggs and larvae

    USGS Publications Warehouse

    Holland, L.E.

    1987-01-01

    Short-term dewatering of nearshore spawning areas often occurs during passage of commercial tows in the upper Mississippi River as well as in other navigated river systems. This phenomenon was examined experimentally to identify potential effects on survival of fish eggs and larvae. Early life stages of walleyes (Stizostedion vitreum vitreum ) and northern pike (Esox lucius ) were dewatered 2 min in laboratory studies at intervals of either 1, 3, 6, or 12 h from just after fertilization to 10-14 d posthatch. Dewatering did not cause mortality of eggs, but significant mortality of larvae of both species occurred at dewatering frequencies of 1 or 3 h. Therefore, significant mortality first was observed at a frequency equivalent to a mean passage of eight tows per day.

  4. Evaluation of geotextile filtration applying coagulant and flocculant amendments for aquaculture biosolids dewatering and phosphorus removal

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wastes contained in the microscreen backwash discharged from intensive recirculating aquaculture systems were removed and dewatered in simple geotextile bag filters. Three chemical coagulation aids, (aluminum sulfate (alum), ferric chloride, and calcium hydroxide (hydrated lime)), were tested in com...

  5. Investigation of operating variables in the fine coal dewatering and briquetting process

    SciTech Connect

    Kan, S.W.; Wilson, J.W.; Dharman, T.

    1998-04-01

    Illinois basin coals contain minerals, including pyrite, which are finely disseminated in micron-size particles. To liberate these mineral matters from the coal matrix, an ultra-fine grinding operation is required, followed by a wet physical cleaning process, such as column flotation. However, the resulting product possesses large surface areas that conventional dewatering techniques cannot perform effectively, and this creates transportation, storage and handling problems at utility plants. To take full advantage of these cleaning technologies, a new dewatering and coal consolidation method must be developed at the downstream end of the deep coal-cleaning process. Following an initial study at the University of Missouri-Rolla (UMR), briquetting was chosen to perform the dual purpose of dewatering and consolidating the fine coal. A bitumen-based emulsion, Orimulsion, proved to be an effective binder and dewatering agent in the briquetting process that assisted in the expulsion of water from the fine coal.

  6. Simultaneous dewatering and reconstitution in a high-gravity solid-bowl centrifuge

    SciTech Connect

    Wen, W.W.; Gray, M.L.; Killmeyer, R.P.; Finseth, D.H.

    1994-12-31

    The Pittsburgh Energy Technology Center has developed a dewatering and reconstitution process in which bitumen emulsion is added to a fine clean coal slurry ahead of the dewatering device. The process simultaneously improves dewatering efficiency and reduces dustiness of the fine coal product during subsequent handling. This paper describes the test results from dewatering and reconstitution of fine coal in a 500 lb. per hour continuous bench scale high-gravity solid-bowl centrifuge in PETC`s Coal Preparation Process Research Facility. Test results will be evaluated in terms of type and dosage of emulsion, product moisture and strength, and product handling and dust reduction efficiency. A preliminary cost analysis will also be included.

  7. To enhance the dewatering of vacuum filter by adding surfactant reagent

    SciTech Connect

    Cai, Z.; Wu, J.; Liu, H.; Xu, S.

    1997-12-31

    A vacuum filter is the main equipment for fine coal dewatering and usually the moisture content of the cake is high. It has a number of serious handling problems. To reduce the moisture content of the cake, surfactant is added to the slurry which is fed to the filter system to enhance dewatering efficiency. Different kinds of surfactant have been used in the laboratory filter system. A variety of tests have been done and the factors which influence dewatering are investigated. Four of the surfactants have good dewatering efficiency. The moisture contents are decreased 5% or so. Two of them have been used in a commercial process. The method is very simple and will solve an excess moisture problem of coal preparation plants.

  8. Low Cost, Low Energy, Method of Dewatering Cultures of the Green Microalgae Nannochloris oculata: Electrocoagulation 

    E-print Network

    Murdock, Jared

    2014-05-01

    ; a low cost, low energy method of dewatering cultures of microalgae. The objectives of this research focus on recognizing parameters that influence the overall efficiency of the process, effective electrode materials, and finally directional...

  9. The study and practice of clean coal pressure filter and dewatering process

    SciTech Connect

    Xie, G.; Wu, L.; Ou, Z.

    1999-07-01

    This paper introduces the current status of dewatering of the flotation clean coal and the problems in China. The industrial application of the dewatering process and the newly developed clean coal pressure filter is represented. And the results indicated that this filter press possesses such advantages as fast speed in filter lower moisture in filter cake, convenience in operation, obvious saving on energy, etc. It will have a broad applications.

  10. Combined method for simultaneously dewatering and reconstituting finely divided carbonaceous material

    SciTech Connect

    Wen, Wu-Wey; Deurbrouck, Albert W.

    1990-01-01

    A finely-divided carbonaceous material is dewatered and reconstituted in a combined process by adding a binding agent directly into slurry of finely divided material and dewatering the material to form a cake or consolidated piece which can be hardened by drying at ambient or elevated temperatures. Alternatively, the binder often in the form of a crusting agent is sprayed onto the surface of a moist cake prior to curing.

  11. Prevention partition for land subsidence induced by engineering dewatering in Shanghai

    NASA Astrophysics Data System (ADS)

    Wang, J. X.; Liu, X. T.; Yang, T. L.

    2015-11-01

    Land subsidence in shanghai has been found for more than 70 years. In the early years, it was mainly caused by groundwater exploitation. In recent years, engineering dewatering in shallow ground (within 90 m) has become a major source for land subsidence in the rapid urbanization course. A management partition of land subsidence induced by foundation pit dewatering for the first confined aquifer was suggested.

  12. Ultrafine coal single stage dewatering and briquetting process. Technical report, September 1--November 30, 1994

    SciTech Connect

    Wilson, J.W.; Honaker, R.Q.

    1994-12-31

    It is well known that a large portion of the pyrite particles in the coal seams of the Illinois Basin, are finely disseminated within the coal matrix. In order to liberate these micron size pyrite particles, one must use a fine grinding operation. The ultrafine coal particles that are produced are difficult to dewater and they create problems in coal transportation as well as in its storage and handling at utility plants. The objective of this research project is to combine ultrafine coal dewatering and briquetting processes into a single stage operation. This will be accomplished by the use of bitumen based emulsions for dewatering and a compaction device for briquetting. During this reporting period, two types of coal samples have been tested for use in the dewatering and briquetting processes. These tests were carried out in conjunction with a selected hydrophobic binder as the dewatering reagent and an uniaxial hydraulic press. The influence of compaction pressure and binder concentration (2 to 5%) on the performance of coal pellets have been evaluated in terms of their water and wear resistance. A laboratory scale ultrafine coal dewatering and briquetting extruder that can be operated continuously for coal pellets fabrication, has been designed and built, and will be available for testing in the next quarter.

  13. Ultrafine coal single stage dewatering and briquetting process. Technical report, December 1, 1994--February 28, 1995

    SciTech Connect

    Wilson, J.W.

    1996-03-01

    It is well known that a large portion of the pyrite particles in the coal seams of the Illinois Basin, are finely disseminated within the coal matrix. In order to liberate these micron size pyrite particles, one must use a fine grinding operation. The ultrafine coal particles that are produced are difficult to dewater and they create problems in coal transportation as well as in its storage and handling at utility plants. The objective of this research project is to combine ultrafine coal dewatering and briquetting processes into a single stage operation. This will be accomplished by the use of bitumen based emulsions for dewatering and a compaction device for briquetting. During this reporting period, two types of coal samples have been tested for use in the dewatering and briquetting processes. These tests were carried out using Orimulsion as the dewatering reagent. A ram extruder that can be operated continuously is used to fabricate dewatered pellets. The influence of compaction pressure, curing time, binder concentration (2% to 5%), particle size, and compacting time on the performance of coal pellets have been evaluated in terms of their water resistance and wear vulnerability.

  14. Growth of microalgal biomass on supernatant from biosolid dewatering.

    PubMed

    Ficara, E; Uslenghi, A; Basilico, D; Mezzanotte, V

    2014-01-01

    The paper reports the results of an experiment to assess the feasibility of including a photobioreactor within the design of a wastewater treatment plant, growing microalgae on the centrate from anaerobic sludge dewatering. The growth of algal biomass would take advantage of the available nitrogen and provide a substrate for biogas production by anaerobic digestion. Tests were carried out by semi-continuously feeding a photobioreactor with a centrate-effluent blend and by increasing the fraction of centrate. The experimental results show that the centrate does not induce any toxicity and, on the contrary, can be well utilized by microalgae, whose average specific growth rate (?), on centrate as such, was between 0.04 and 0.06 d(-1). The maximum biomass concentration in the photobioreactor effluent was 1.6 gSS/L at 10 days HRT (hydraulic retention time). Methane production tests led to biochemical methane production values of 335 ± 39, and 284 ± 68 mL 0°C, 1 atm CH4/g VS for the two tested samples, in agreement with literature values. Settling tests show that the settling capacity of microalgae, although satisfactory, could be effectively improved after mixing with activated sludge, confirming the potential to use the existing primary settler for microalgae thickening in order to feed microalgae for anaerobic digestion with primary/secondary sludge. PMID:24569293

  15. Pyrolysis characteristics and kinetic analysis of different dewatered sludge.

    PubMed

    Zhang, Qiang; Liu, Huan; Liu, Peng; Hu, Hongyun; Yao, Hong

    2014-10-01

    Pyrolysis behavior and kinetic properties of four different sludge, including raw sludge and three sludge respectively dewatered with FeCl3/CaO, FeCl3/CaO/coal and Fenton's reagent (Fe(2+)+H2O2)/CaO, were analyzed by using thermogravimetry coupled with Fourier transform infrared spectrometry (TG-FTIR). The results show that organics of raw sludge mainly decomposed at 378-676K, and the decomposition temperature of conditioned sludge was prolonged to 823K. Addition of coal and catalysis of CaO/ferric salt both promoted sludge pyrolysis, leading to more NH3, CH4 and CO productions. Compared with dry sludge, wet sludge pyrolysis was hard to finish completely, and the first peak of organics' decomposition appeared at higher temperature (about 573K). Additionally, the global reaction model was suited to determine kinetic parameters, which showed that dry sludge conditioned with more CaO addition had higher E values than those of dry raw sludge. Opposite results were obtained when sludge samples were wet. PMID:25151077

  16. Development of the electroacoustic dewatering (EAD) process for fine/ultrafine coal: Third quarterly progress report, (April--June 1989)

    SciTech Connect

    Not Available

    1989-07-18

    Battelle, in cooperation with the Electric Power Research Institute (EPRI), Ashbrook-Simon-Hartley (ASH), Kaiser Engineers (KE), Lewis Corporation, and Professor S.H. Chiang of the University of Pittsburgh, is developing an advanced process for the dewatering of fine and ultrafine coals. The advanced process, called Electroacoustic Dewatering (EAD), capitalizes on the adaptation of synergistic effects of electric and acoustic fields to commercial coal dewatering systems, such as belt filter presses. 2 figs., 2 tabs.

  17. Inactivation mechanisms of bacterial pathogen indicators during electro-dewatering of activated sludge biosolids.

    PubMed

    Navab Daneshmand, Tala; Beton, Raphaël; Hill, Reghan J; Gehr, Ronald; Frigon, Dominic

    2012-09-01

    Electro-dewatering is an energy-efficient technology in which an electric field can increase the dryness of biosolids from secondary wastewater treatment from 15% w/w to 30-50% w/w. Here, we address bacterial pathogen indicators inactivation (total coliforms, Escherichia coli and aerobic endospores) during electro-dewatering, investigating the roles of electrochemically generated oxidants, extreme pH, and high temperature (from Joule heating). Our results demonstrate that temperature is the primary factor affecting total coliforms and E. coli inactivation. First, several electro-dewatering cycles were used to increase sludge temperature to about 100 °C after 6 min, during which time the average pH decreased from 7 to 3.6 after 10 min. Total coliforms and E. coli MPNs reached their detection limits after 6 min (with 4-5 logs of inactivation for total coliforms and 3-4 logs for E. coli). In contrast, aerobic endospores were not inactivated under these conditions; rather, their germination appeared to be stimulated by 6-8 min of electro-dewatering. Second, the dewatering cake was separated into four horizontal layers. After 8 min of electro-dewatering, the pH in the top layers decreased to 3, whereas the pH in the bottom layers increased to 8. Inactivation of total coliforms and E. coli in the sludge cake was similar in all layers, increasing with time, suggesting that oxidants and extreme pH are secondary inactivation factors. Finally, electrodes were cooled to maintain a temperature less than 34 °C. Although pH decreased significantly after 12 min of electro-dewatering, there was no significant bacterial pathogen indicator inactivation at low temperature. PMID:22677501

  18. Development of A Continuous Process for Displacement Dewatering

    SciTech Connect

    Dave Beck

    2006-10-30

    The subject of this contract was to investigate the viability of a new process for dewatering paper called displacement pressing. The term “displacement pressing” was coined in the 1980s by researchers to describe a paper dewatering process where air is blown through a sheet of paper while it is being pressed. It was shown at that time that the combination of air and low pressing force could dramatically increase both sheet bulk and sheet solids which in theory would translate into huge savings in energy and fiber consumption. But there was a catch. Although the research results were dramatic, no one could figure out a commercially viable process to carry out displacement pressing. All research work had been done with batch processes, and there was no obvious way to convert these processes into a continuous process. By the end of the early1990’s no one was researching in this area because no continuous process existed. Recently we proposed a new method to carry out displacement pressing. Our process uses special pressing fabrics and a special 4 roll press that we call a “Beck Cluster Press” or BCP. The BCP provides a pressurized atmosphere that acts on a moving web of paper and fabrics. The special fabrics designed for this process use this atmosphere to press the sheet and at the same time, these special fabrics force air through the sheet to carry out displacement pressing. 1 Because of the complexity and cost of building the first functioning BCP, a simple simulator was built to confirm and study the process. Although results from this simulator were extremely favorable, financial times were hard in the paper industry. We are grateful for the DOE contract that allowed us to continue research that showed the tremendous benefits of displacement pressing. Specifically, accomplishments from the DOE contract are as follows: 1. A narrow (5” wide sheet) lab Beck Cluster Press (BCP) was started up, and made operational. This press accepts hand sheets and displacement presses them at conditions that duplicate commercial conditions for dwell time, and pressure. 2. The lab BCP machine was used to verify simulator results. Results showed the lab BCP gave paper dryness that exceeded simulator results for dryness. 3. Sheet samples were obtained for several paper grades. These samples were pressed conventionally (shoe and roll presses) and with the lab BCP. Results showed significant gains in bulk (5-48%) compared to commercially pressed sheets while producing similar or higher dryness. These results verified the predictions of the earlier research papers. 4. Sheet bulk exceeded the Agenda 2020 goal a 7% increase. This increase in bulk was reported by Agenda 2020 as being worth about 3 billion dollars per year in fiber savings. Potential energy savings due to dryness savings could be worth $1 billion per year. However energy savings and fiber savings are inter-related so while savings are likely in both energy and fiber at the same time, increasing one will cause the other to decrease. 5. Based on the significant results of small-scale BCP trials, a 1m pilot BCP press stand was built to determine scalability of the process. 6. 1m pilot press stand was started up. This machine was shown to hold design pressure. Drive issues however prevented operation at operating speed and pressure during the contact period. Improvements to the drive system since the end of the DOE contract have allowed us to reach operating pressure and speed. 7. The last DOE objective of passing paper through the 1m BCP was not reached due to drive issues and the desire to study and qualify sealing systems. All other original objectives and the added objective (by contract revision) of this ambitious project have been met. 8. Several paper companies have showed interest in helping us commercialize this process. Interest is so high that these companies appear willing to invest in further development.

  19. POC-SCALE TESTING OF AN ADVANCED FINE COAL DEWATERING EQUIPMENT/TECHNIQUE

    SciTech Connect

    X.H. Wang; J. Wiseman; D.J. Sung; D. McLean; William Peters; Jim Mullins; John Hugh; G. Evans; Vince Hamilton; Kenneth Robinette; Tim Krim; Michael Fleet

    1999-08-01

    Dewatering of ultra-fine (minus 150 {micro}m) coal slurry to less than 20% moisture is difficult using the conventional dewatering techniques. The main objective of the project was to evaluate a novel surface modification technique, which utilizes the synergistic effect of metal ions and surfactants in combination for the dewatering of ultra-fine clean-coal slurries using various dewatering techniques on a proof-of-concept (POC) scale of 0.5 to 2 tons per hour. The addition of conventional reagents and the application of coal surface modification technique were evaluated using vacuum filtration, hyperbaric (pressure) filtration, ceramic plate filtration and screen-bowl centrifuge techniques. The laboratory and pilot-scale dewatering studies were conducted using the fine-size, clean-coal slurry produced in the column flotation circuit at the Powell Mountain Coal Company, St. Charles, VA. The pilot-scale studies were conducted at the Mayflower preparation plant in St. Charles, VA. The program consisted of nine tasks, namely, Task 1--Project Work Planning, Task 2--Laboratory Testing, Task 3--Engineering Design, Task 4--Procurement and Fabrication, Task 5--Installation and Shakedown, Task 6--System Operation, Task 7--Process Evaluation, Task 8--Equipment Removal, and Task 9--Reporting.

  20. Study of a solvent/binder combination for viscosity reduction of Orimulsion in fine coal dewatering

    SciTech Connect

    Kan, S.W.; Wilson, J.W.; Dharman, T.; Aksoy, B.S.

    1998-04-01

    To effectively liberate finely disseminated minerals from a coal matrix, a pulverization operation is needed. In this process fine coal particles are formed that possess large surface areas that are difficult to dewater, and create transportation, storage and handling problems at coal cleaning and utility plants. Using both laboratory and pilot scale models, research work conducted at the Department of Mining Engineering at University of Missouri - Rolla (UMR) on a single-stage fine coal dewatering and briquetting technique, has shown the potential of briquetting to enhance the handling, transportation, and storage of fine coal. The operation uses a hydrophobic binder as the dewatering and briquetting agent and requires a compaction device, specifically, a commercial-scale briquetting machine. In the single-stage dewatering/briquetting process, a bitumen-in-water emulsion (Orimulsion), which has high viscosity even at room temperature, was selected as the binder. Due to the tacky nature of the binder, it was felt that by reducing its viscosity using a solvent, the binder could more effectively coat the fine coal surfaces. This study investigated the efficiency of a solvent/binder combination for reducing the viscosity of the Orimulsion for the dewatering of fine coal, and making robust briquettes from predominantly -400 mesh coal particles.

  1. Impact of environmental dewatering of Lower Granite and Little Goose reservoirs on benthic invertebrates and macrophytes

    SciTech Connect

    Cushing, C.E.

    1993-09-01

    An investigation into the effects of dewatering on the benthic fauna in Lower Granite and Little Goose reservoirs was undertaken. Benthos in both the soft bottom regions of the reservoirs as well as those inhabiting the rock rip-rap along the shoreline were studied. These organisms provide an important food resource for both migrating salmonids and resident fish species; thus, impacts of contemplated dewatering schemes require evaluation. The results of these studies indicate that there were no significant, long-term impacts to the soft bottom benthos as a result of dewatering in Little Goose Reservoir. In fact, higher numbers of some taxa indicate that there may have been a washout of these organisms from Lower Granite Reservoir with subsequent deposition in the upper reaches of Little Goose Reservoir. This should be accompanied by a coincident decrease in these organisms in Lower Granite Reservoir. However, we did not have pre-dewatering samples from Lower Granite Reservoir with which we could compare post-filling samples to determine if the dewatering resulted in lower benthic populations.

  2. Experience dewatering fine coal in solidbowl centrifuges at the York Canyon preparation plant

    SciTech Connect

    Alderman, J.K.

    1995-08-01

    In 1990, a study was undertaken at P&M`s York Canyon preparation plant to evaluate options for dewatering froth flotation product. The existing vacuum disc filter was in need of replacement from wear and neglect, and analysis of the feed to the filter showed that only 7% of the particles were larger than 0.15mm (100 mesh) while nearly 60% of the particles were finer than 0.45mm (325 mesh). Size analysis of the filter cake indicated a mass mean diameter (MMD) of 0.092mm and surface moisture of the filter cake was 33%. Preliminary modeling indicated that a surface moisture of 26% might be attainable for this cake with efficient mechanical dewatering. Based upon the fineness of the feed and the need to replace the filter, in 1991 P&M conducted the field testing with a pilot-scale Sharples high-G solidbowl centrifuge. Data from the pilot scale tests led to the conclusion that the solidbowl centrifuges could recover over 90% of feed solids while providing a surface moisture of about 25% in the product cake. When a decision was made in 1992 to replace the existing plant at York Canyon with a new, larger preparation plant, the commercial scale Sharples high-G solidbowl centrifuges were selected for fine dewatering. The following discussion deals with the plant fine coal dewatering circuitry, start-up problems, remedial actions, and machine dewatering performance.

  3. Thermal conductivity characteristics of dewatered sewage sludge by thermal hydrolysis reaction.

    PubMed

    Song, Hyoung Woon; Park, Keum Joo; Han, Seong Kuk; Jung, Hee Suk

    2014-12-01

    The purpose of this study is to quantify the thermal conductivity of sewage sludge related to reaction temperature for the optimal design of a thermal hydrolysis reactor. We continuously quantified the thermal conductivity of dewatered sludge related to the reaction temperature. As the reaction temperature increased, the dewatered sludge is thermally liquefied under high temperature and pressure by the thermal hydrolysis reaction. Therefore, the bound water in the sludge cells comes out as free water, which changes the dewatered sludge from a solid phase to slurry in a liquid phase. As a result, the thermal conductivity of the sludge was more than 2.64 times lower than that of the water at 20. However, above 200, it became 0.704 W/m* degrees C, which is about 4% higher than that of water. As a result, the change in physical properties due to thermal hydrolysis appears to be an important factor for heat transfer efficiency. Implications: The thermal conductivity of dewatered sludge is an important factor the optimal design of a thermal hydrolysis reactor. The dewatered sludge is thermally liquefied under high temperature and pressure by the thermal hydrolysis reaction. The liquid phase slurry has a higher thermal conductivity than pure water. PMID:25562934

  4. POC-Scale Testing of an Advanced Fine Coal Dewatering Equipment/Technique.

    SciTech Connect

    Tao, D.; Groppo, J.G.; Parekh, B.K.

    1997-11-05

    Froth flotation technique is an effective and efficient process for recovering of ultra-fine (minus 74 mm) clean coal. Economical dewatering of an ultra-fine clean-coal product to a 20% level moisture will be an important step in successful implementation of the advanced cleaning processes. This project is a step in the Department of Energy`s program to show that ultra-clean coal could be effectively dewatered to 20% or lower moisture using either conventional or advanced dewatering techniques. The cost-sharing contract effort is for 36 months beginning September 30, 1994. This report discusses technical progress made during the quarter from July 1 - September 30, 1997.

  5. POC-Scale Testing of an Advanced Fine Coal Dewatering Equipment/Technique.

    SciTech Connect

    Tao, D.; Groppo, J.G.; Parekh, B.K.

    1997-12-31

    Froth flotation technique is an effective and efficient process for recovering of ultra-fine (minus 74 mm) clean coal. Economical dewatering of an ultra-fine clean coal product to a 20% level moisture will be an important step in the successful implementation of the advanced cleaning processes. This project is a step in the Department of Energy`s program to show that ultra-clean coal could be effectively dewatered to 20% or lower moisture using either conventional or advanced dewatering techniques. The cost-sharing contract effort is for 36 months beginning September 30, 1994. This report discusses technical progress made during the quarter from April 1 - June 30, 1997.

  6. Improved electroacoustic dewatering (EAD) belt press for food products. Phase 3, Technical progress report

    SciTech Connect

    Not Available

    1994-02-01

    Battelle`s electroacoustic dewatering (EAD) process improves the performance of mechanical dewatering processes for several food products (such as corn fiber) by superimposing electric and ultrasonic fields. EAD has the potential to save 0.027 to 0.035 quad/yr energy by 1995 in the food processing industry, which consumed 0.15 to 0.18 quad in 1986. This report covers Phase III for demonstrating the EAD prototype on corn wet milling products (corn fiber and gluten); only Task 1 (prototype preparation and planning) was completed. EAD performance was examined in the laboratory; availability of a test site was examined. The single-roll, postdewatering EAD belt press prototype can accept material predewatered by a screw press, centrifuge, or any other mechanical dewatering device. The two-belt system, utilizing a copper-polymer cathode belt, performed as well as the three-belt system used in Phase II.

  7. POC-scale testing of an advanced fine coal dewatering equipment/technique

    SciTech Connect

    1998-09-01

    Froth flotation technique is an effective and efficient process for recovering of ultra-fine (minus 74 pm) clean coal. Economical dewatering of an ultra-fine clean-coal product to a 20% level moisture will be an important step in successful implementation of the advanced cleaning processes. This project is a step in the Department of Energy`s program to show that ultra-clean coal could be effectively dewatered to 20% or lower moisture using either conventional or advanced dewatering techniques. The cost-sharing contract effort is for 36 months beginning September 30, 1994. This report discusses technical progress made during the quarter from July 1 - September 30, 1997.

  8. POC-SCALE TESTING OF AN ADVANCED FINE COAL DEWATERING EQUIPMENT/TECHNIQUE

    SciTech Connect

    B.K. PAREKH; D. TAO; J.G. GROPPO

    1998-02-03

    The main objective of the proposed program is to evaluate a novel surface modification technique, which utilizes the synergistic effect of metal ions-surfactant combination, for dewatering of ultra-fine clean coal on a proof-of-concept scale of 1 to 2 tph. The novel surface modification technique developed at the UKCAER will be evaluated using vacuum, centrifuge, and hyperbaric filtration equipment. Dewatering tests will be conducted using the fine clean-coal froth produced by the column flotation units at the Powell Mountain Coal Company, Mayflower Preparation Plant in St. Charles, Virginia. The POC-scale studies will be conducted on two different types of clean coal, namely, high-sulfur and low-sulfur clean coal. The Mayflower Plant processes coals from five different seams, thus the dewatering studies results could be generalized for most of the bituminous coals.

  9. Evaluation of hyperbaric filtration for fine coal dewatering. Third quarterly technical progress report, March 1, 1993--May 31, 1993

    SciTech Connect

    Parekh, B.K.; Hogg, R.; Fonseca, A.

    1993-09-01

    The main objectives of the project are to investigate the fundamental aspects of particle-liquid interaction in fine coal dewatering, to conduct laboratory and pilot plant studies on the applicability of hyperbaric filter systems and to develop process conditions for dewatering of fine clean coal to less than 20 percent moisture. Progress is described.

  10. Electro-dewatering of wastewater sludge: An investigation of the relationship between filtrate flow rate and electric current.

    PubMed

    Olivier, Jérémy; Conrardy, Jean-Baptiste; Mahmoud, Akrama; Vaxelaire, Jean

    2015-10-01

    Compared to conventional dewatering techniques, electrical assisted mechanical dewatering, also called electro-dewatering (EDW) is an alternative and an effective technology for the dewatering of sewage sludge with low energy consumption. The objectives of this study were to evaluate the dewatering performance and to determine the influence of the process parameters (e.g. applied electric current, applied voltage, and the initial amount of dry solids) on the kinetics of EDW-process for activated urban sludge. Also significant efforts have been devoted herein to provide comprehensive information about the EDW mechanisms and to understand the relationship between these operating conditions with regards to develop a qualitative and quantitative understanding model of the electro-dewatering process and then produce a robust design methodology. The results showed a very strong correlation between the applied electric current and the filtrate flow rate and consequently the electro-dewatering kinetics. A higher applied electric current leads to faster EDW kinetics and a higher final dry solids content. In contrast, the results of this work showed a significant enhancement of the dewatering kinetics by decreasing the mass of the dry solids introduced into the cell (commonly known as the sludge loading). PMID:26304592

  11. A Guide for Developing Standard Operating Job Procedures for the Sludge Conditioning & Dewatering Process Wastewater Treatment Facility. SOJP No. 11.

    ERIC Educational Resources Information Center

    Schwing, Carl M.

    This guide describes standard operating job procedures for the sludge conditioning and dewatering process of wastewater treatment facilities. In this process, sludge is treated with chemicals to make the sludge coagulate and give up its water more easily. The treated sludge is then dewatered using a vacuum filter. The guide gives step-by-step…

  12. Evaluation of hyperbaric filtration for fine coal dewatering. Seventh quarterly technical progress report, April 1, 1994--June 30, 1994

    SciTech Connect

    Parekh, B.K.; Hogg, R.; Fonseca, A.

    1994-10-01

    The main objectives of the project are to investigate the fundamental aspects of particle-liquid interaction in fine coal dewatering, to conduct laboratory and pilot plant studies on the applicability of hyperbaric filter systems and to develop process conditions for dewatering of fine clean coal to less than 20 percent moisture. This project is oriented into three phases.

  13. Dewatering as a non-toxic control of nuisance midge larvae in algal wastewater treatment floways.

    PubMed

    Keller, Troy A; Husted, Emily M

    2015-01-01

    Attached-algae floways have tremendous potential for use in wastewater treatment because natural algal communities show high nutrient removal efficiencies, have low operating costs, and are easy to maintain. Algal wastewater floways may also serve as a sustainable option for producing renewable energy because algae grow rapidly, are easily harvested, and can serve as a source of biomass for biofuel. However, pests such as chironomids (Diptera) colonize open channel periphyton floways and their larvae damage the biofilms. While pesticides can control midge larvae, little information is known about alternative, non-toxic controls. This study examined the effectiveness of periodic, short-term dewatering (4 hours every 9 days) on midge abundance and periphyton growth in 16 recirculating, outdoor floways (3 m long, 0.1 m wide). We compared midge abundance and algal accumulation (chlorophyll a, b, c, and pheophytin) among control (n=8) and dewatered (n=8) floways filled with secondarily treated wastewater (27 days, 10 hours of daylight). Dewatered flumes had 42% fewer midges and 28-49% lower algal productivity (as measured by chlorophyll a, b, c, and pheophytin pigments). Chlorophyll a production rates averaged (±1 SD) 0.5±0.2 ?g/cm2/day in control floways compared to 0.3±0.1 ?g/cm2/day dewatered floways. Short-term dewatering effectively reduced midges but also damaged periphyton. To maximize the recovery of periphyton biomass, operators should harvest periphyton from floways during dewatering events before periphyton is damaged by desiccation or direct exposure to sunlight. PMID:25607663

  14. Electroacoustic dewatering of food and other suspensions: Phase 1, Final report

    SciTech Connect

    Muralidhara, H.S.; Beard, R.; Jirjis, B.; Chauhan, S.P.; Kim, B.C.; Criner, C.; Senapati, N.

    1987-03-26

    A research and development program is being conducted to demonstrate application of the Electroacoustic Dewatering (EAD) technology to food processing with the main goal of achieving significant energy savings. The Phase I of the two-phase program has been completed. Objectives of Phase I were to demonstrate technical feasibility of the EAD process to a wide range of food products and to select preferred commercial dewatering units for adaptation of the EAD technology to be used as process research units (PRU's) in Phase II.

  15. Evaluation of thickening and dewatering characteristics of SRC-I wastewater treatment sludges. Final technical report

    SciTech Connect

    Not Available

    1984-05-01

    The SRC-I Demonstration Plant in Newman, Kentucky, will generate several different sludges as a result of providing extensive wastewater treatment. Because construction of this plant has been postponed indefinitely, there has been an opportunity to generate additional data pertinent to waste treatment. Accordingly, this report presents the results of a study on the thickening and dewatering characteristics of several of the wastewater treatment sludges. The study included: evaluation of chemical conditioning agents; aerobic digestion of biological sludges; gravity thickening; and the relative effectiveness of dewatering by centrifuge, vacuum filter, belt filter, and pressure filter. Sludges were tested individually and in combination. The results indicated that the biological sludge could be best dewatered by pressure filtration. The chemical sludges should be combined prior to dewatering, which should be provided by a belt filter. The tar acid sludge will be kept separate, due to its low pH, and ultimate disposal will be by incineration. The tar acid sludge was more concentrated than had been expected. As a result, thickening, rather than centrifuging, is the recommended treatment for this sludge. All sludges were tested for leachate toxicity by the extraction procedure method. The results were negative, indicating the sludges are non-hazardous in heavy metal concentrations, according to RCRA classification. The test results have identified design changes for the proposed wastewater treatment facilities.

  16. Optimisation of extraction and sludge dewatering efficiencies of bio-flocculants extracted from Abelmoschus esculentus (okra).

    PubMed

    Lee, Chai Siah; Chong, Mei Fong; Robinson, John; Binner, Eleanor

    2015-07-01

    The production of natural biopolymers as flocculants for water treatment is highly desirable due to their inherent low toxicity and low environmental footprint. In this study, bio-flocculants were extracted from Hibiscus/Abelmoschus esculentus (okra) by using a water extraction method, and the extract yield and its performance in sludge dewatering were evaluated. Single factor experimental design was employed to obtain the optimum conditions for extraction temperature (25-90 °C), time (0.25-5 h), solvent loading (0.5-5 w/w) and agitation speed (0-225 rpm). Results showed that extraction yield was affected non-linearly by all experimental variables, whilst the sludge dewatering ability was only influenced by the temperature of the extraction process. The optimum extraction conditions were obtained at 70 °C, 2 h, solvent loading of 2.5 w/w and agitation at 200 rpm. Under the optimal conditions, the extract yield was 2.38%, which is comparable to the extraction of other polysaccharides (0.69-3.66%). The bio-flocculants displayed >98% removal of suspended solids and 68% water recovery during sludge dewatering, and were shown to be comparable with commercial polyacrylamide flocculants. This work shows that bio-flocculants could offer a feasible alternative to synthetic flocculants for water treatment and sludge dewatering applications, and can be extracted using only water as a solvent, minimising the environmental footprint of the extraction process. PMID:25929197

  17. 46 CFR 28.815 - Bilge pumps, bilge piping, and dewatering systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... fire pump required by 46 CFR 28.820, a bilge pump may be used for other purposes. (g) Each vessel must comply with the oil pollution prevention requirements of 33 CFR parts 151 and 155. ... 46 Shipping 1 2011-10-01 2011-10-01 false Bilge pumps, bilge piping, and dewatering systems....

  18. Impact of Joule Heating and pH on Biosolids Electro-Dewatering.

    PubMed

    Navab-Daneshmand, Tala; Beton, Raphaël; Hill, Reghan J; Frigon, Dominic

    2015-05-01

    Electro-dewatering (ED) is a novel technology to reduce the overall costs of residual biosolids processing, transport, and disposal. In this study, we investigated Joule heating and pH as parameters controlling the dewaterability limit, dewatering rate, and energy efficiency. Temperature-controlled electrodes revealed that Joule heating enhances water removal by increasing evaporation and electro-osmotic flow. High temperatures increased the dewatering rate, but had little impact on the dewaterability limit and energy efficiency. Analysis of horizontal layers after 15-min ED suggests electro-osmotic flow reversal, as evidenced by a shifting of the point of minimum moisture content from the anode toward the cathode. This flow reversal was also confirmed by the pH at the anode being below the isoelectric point, as ascertained by pH titration. The important role of pH on ED was further studied by adding acid/base solutions to biosolids prior to ED. An acidic pH reduced the biosolids charge while simultaneously increasing the dewatering efficiency. Thus, process optimization depends on trade-offs between speed and efficiency, according to physicochemical properties of the biosolids microstructure. PMID:25494946

  19. 46 CFR 28.815 - Bilge pumps, bilge piping, and dewatering systems.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... fire pump required by 46 CFR 28.820, a bilge pump may be used for other purposes. (g) Each vessel must comply with the oil pollution prevention requirements of 33 CFR parts 151 and 155. ... 46 Shipping 1 2014-10-01 2014-10-01 false Bilge pumps, bilge piping, and dewatering systems....

  20. Effects of different sludge disintegration methods on sludge moisture distribution and dewatering performance.

    PubMed

    Jin, Lingyun; Zhang, Guangming; Zheng, Xiang

    2015-02-01

    A key step in sludge treatment is sludge dewatering. However, activated sludge is generally very difficult to be dewatered. Sludge dewatering performance is largely affected by the sludge moisture distribution. Sludge disintegration can destroy the sludge structure and cell wall, so as change the sludge floc structure and moisture distribution, thus affecting the dewatering performance of sludge. In this article, the disintegration methods were ultrasound treatment, K2FeO4 oxidation and KMnO4 oxidation. The degree of disintegration (DDCOD), sludge moisture distribution and the final water content of sludge cake after centrifuging were measured. Results showed that three disintegration methods were all effective, and K2FeO4 oxidation was more efficient than KMnO4 oxidation. The content of free water increased obviously with K2FeO4 and KMnO4 oxidations, while it decreased with ultrasound treatment. The changes of free water and interstitial water were in the opposite trend. The content of bounding water decreased with K2FeO4 oxidation, and increased slightly with KMnO4 oxidation, while it increased obviously with ultrasound treatment. The water content of sludge cake after centrifuging decreased with K2FeO4 oxidation, and did not changed with KMnO4 oxidation, but increased obviously with ultrasound treatment. In summary, ultrasound treatment deteriorated the sludge dewaterability, while K2FeO4 and KMnO4 oxidation improved the sludge dewaterability. PMID:25662234

  1. Hydrologic considerations in dewatering and refilling Lake Carlton : Orange and Lake Counties, Florida

    USGS Publications Warehouse

    Anderson, Warren; Hughes, G.H.

    1977-01-01

    Lake Carlton straddles the line between Lake and Orange Counties in central Florida. The 382-acre lake is highly eutrophic and subject to virtually perpetual algal blooms. The Florida Game and Fresh Water Fish Commission has proposed to restore the lake to a less eutrophic state by dewatering the lake long enough to allow the muck on its bottom to dry and compact. Lake Carlton would be permanently sealed off from Lake Carlton. On the assumption that the seasonal rainfall would be normal, and that the dewatering phase would begin on March 1, the predicted time required to dewater the lake at a pumping rate of 50,000 gpm (gallons per minute) is 21 days. The average rate of pumping required to maintain the lake in a dewatered condition is computed to be 2,400 gpm. If pumping is ended May 31, the predicted altitude to which the lake would recover by October 31 as a result of net natural input is 56.2 feet above sea level. Raising the lake level to 63 feet above sea level by October 31 would require that the net natural input be supplemented at an average rate of about 4,860 gpm between May 31 and October 31. (Woodard-USGS)

  2. 46 CFR 28.815 - Bilge pumps, bilge piping, and dewatering systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... fire pump required by 46 CFR 28.820, a bilge pump may be used for other purposes. (g) Each vessel must comply with the oil pollution prevention requirements of 33 CFR parts 151 and 155. ... 46 Shipping 1 2012-10-01 2012-10-01 false Bilge pumps, bilge piping, and dewatering systems....

  3. DEWATERING WASTEWATER TREATMENT SLUDGE BY CLATHRATE FREEZING: A BENCH-SCALE FEASIBILITY STUDY

    EPA Science Inventory

    Laboratory studies were performed to prove the concept and feasibility for a novel technology to dewater sludges. This involves the formation of solid hydrate crystals of water and specific clathrate-forming agents followed by separation of the hydrate crystal solids from the slu...

  4. 46 CFR 28.815 - Bilge pumps, bilge piping, and dewatering systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... fire pump required by 46 CFR 28.820, a bilge pump may be used for other purposes. (g) Each vessel must comply with the oil pollution prevention requirements of 33 CFR parts 151 and 155. ... 46 Shipping 1 2010-10-01 2010-10-01 false Bilge pumps, bilge piping, and dewatering systems....

  5. DEVELOPMENT OF A NEW GRAVITY SEDIMENTATION PROCESS FOR DEWATERING FLUE GAS CLEANING WASTES

    EPA Science Inventory

    The report gives results of a project to develop and test a novel system for dewatering flue gas cleaning (FGC) wastes at the pilot plant level. In this new system, the clarification and thickening functions are conducted in separate, but interconnected, pieces of equipment. The ...

  6. 46 CFR 28.815 - Bilge pumps, bilge piping, and dewatering systems.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... fire pump required by 46 CFR 28.820, a bilge pump may be used for other purposes. (g) Each vessel must comply with the oil pollution prevention requirements of 33 CFR parts 151 and 155. ... 46 Shipping 1 2013-10-01 2013-10-01 false Bilge pumps, bilge piping, and dewatering systems....

  7. Charge-tunable polymers as reversible and recyclable flocculants for the dewatering of microalgae.

    PubMed

    Morrissey, Kathryn L; He, Chunlin; Wong, Min Hao; Zhao, Xueying; Chapman, Rebeccah Z; Bender, Shana L; Prevatt, William D; Stoykovich, Mark P

    2015-01-01

    Microalgae-derived biofuels have potential advantages over other renewable, crop-based resources; however, large-scale production is not currently economical due, in part, to challenges in the harvesting step. In this article, we present a novel approach for the dewatering and harvesting of microalgae using flocculants that can be recovered and recycled. Polyampholytes with molecular charges dependent upon pH (ranging from net positively- to net negatively-charged) are used as a model flocculant system and provide reversible electrostatic interactions with the negatively-charged algal cells. These pH-dependent properties allow the polyampholytic flocculants to efficiently desorb from concentrated biomass and, unlike most commercial flocculants that have permanently charged functionalities, be recovered and recycled for further dewatering processes. The behavior of the model polyampholytic flocculants is characterized for the dewatering of Chlorella vulgaris (UTEX 395). The reversible and recyclable flocculants achieve >99% flocculation efficiencies, are recovered at more than 98 wt% yields after biomass dewatering, and can be recycled over five times for flocculation. PMID:25060233

  8. Geotextile filtration performance for lagoon sludges and liquid animal manures dewatering

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maintenance and control of liquid levels in anaerobic lagoons and storage ponds require liquid-solid separation as a pretreatment and periodic removal of accumulated sludges. Until local options become available, sludges can be contained, dewatered, and stored using geotextile filtration. We used a ...

  9. Dewatered sewage biosolids provide a productive larval habitat for stable flies and house flies (Diptera: Muscidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Species diversity and seasonal abundance of muscoid flies (Diptera: Muscidae) developing in biosolid cake (dewatered biosolids) stored at a wastewater treatment facility in northeastern Kansas was evaluated. Emergence traps were deployed 19 May-20 Oct 2009 (22 wk) and 27 May-18 Nov 2010 (25 wk). A t...

  10. Evaluation of reed bed technology to dewater Army wastewater treatment plant sludge. Final report

    SciTech Connect

    Kim, B.J.; Cardenas, R.R.; Chennupati, S.P.

    1993-09-01

    As operator of over 100 small wastewater treatment plants (WWTPs), the Army has an interest in efficient and cost-effective sludge dewatering systems. Many Army wastewater treatment plants use conventional sand-drying beds to dewater sludge. However, sand drying involves costly regular removal of sludge, and sand-drying beds are vulnerable to operational problems with long drying periods during wet weather and sand media clogging. Successful new technologies for sludge treatment in small-scale WWTPs include wedgewater beds, vacuum-assisted beds, and reed-bed systems. This study builds on a previous USACERL evaluation of wedgewater and vacuum-assisted bed performance by compiling operational data from municipal and industrial WWTPs that have reed bed systems to evaluate their potential for Army use. The use of reeds speeds sludge dewatering because the root systems maintain natural drainage channels throughout the sludge volume, and because reeds complement air drying by drawing water into the plant for evapotranspiration. Reed beds were found to be easier to operate and maintain than sand-drying beds, and to virtually eliminate the need for regular sludge removal. Moreover, reed beds can be simply and efficiently retrofited to existing sand-drying beds. Because the Army has large-area drying beds that can be converted to reed beds economically, reed bed systems were found to have a good potential for use at Army WWTPS. Wastewater treatment plant, Sludge dewatering systems, Reed bed technology.

  11. Parameter investigation for decentralised dewatering and solar thermic drying of sludge.

    PubMed

    Wett, B; Demattio, M; Becker, W

    2005-01-01

    The purpose of this paper is an experimental and model assisted investigation of the capabilities of a dewatering system for sewage sludge for decentralised sites. Laboratory and field tests are performed with different initial conditions and the influences of filter medium, initial height, initial total suspended solids, temperature and relative humidity are discussed. The experimental work shows the feasibility of geotextile media for dewatering high water content sewage sludge and that the textile structure is of secondary importance. The specific filter resistance of the sludge cake is found to be the most significant factor in dewatering applications. The mathematical description of the dewatering process is based on the superposition of two models, the Conventional Filtration Theory for the filtration phase and the BT-model for the drying phase. Feasibility and limits of the theoretical approach are evaluated by means of a comparison between measurements and simulated data of cyclic reloading tests. It is found that a better filtration efficiency is achieved at higher TSS and at lower initial height of the slurry layer. Due to the viscosity decrease, a higher temperature enhances not only evaporation, but also filtration rate. PMID:16104407

  12. Centrifugal dewatering and reconstitution of fine coal by the GranuFlow Process

    SciTech Connect

    Wen, W.W.; Utz, B.R.; Killmeyer, R.P.

    1997-12-31

    A continuous pilot-scale test of the GranuFlow Process was conducted using a screen-bowl centrifuge for the dewatering and reconstitution of column flotation concentrate at a coal preparation plant in Virginia. In this test, a slipstream of the fine-clean-coal slurry from the column flotation concentrate was treated with a bitumen emulsion before dewatering. The treated products from the screen-bowl centrifuge appeared to be dry and in a free-flowing granular form, while the untreated products were wet, sticky, and difficult to handle. Specifically, test results indicated that the average moisture contents of the dewatered coal were 35.7, 35.5, 32.6, 29.9, and 26.5 wt% with Orimulsion additions of 0, 0.7, 3.2, 4.8, and 6.4 wt%, respectively. The handleability and dust reduction of the dewatered coal product were also vastly improved. A preliminary cost estimate of using Orimulsion in the GranuFlow Process is also included. Because of the simplicity of the process and the low cost of the bitumen emulsion, the commercialization potential of the GranuFlow Process is significant.

  13. Precision Dual-Aquifer Dewatering at a Low Level Radiological Cleanup in New Jersey

    SciTech Connect

    Gosnell, A. S.; Langman, J. W. Jr.; Zahl, H. A.; Miller, D. M.

    2002-02-27

    Cleanup of low-level radioactive wastes at the Wayne Interim Storage Site (WISS), Wayne, New Jersey during the period October, 2000 through November, 2001 required the design, installation and operation of a dual-aquifer dewatering system to support excavation of contaminated soils. Waste disposal pits from a former rare-earth processing facility at the WISS had been in contact with the water table aquifer, resulting in moderate levels of radionuclides being present in the upper aquifer groundwater. An uncontaminated artesian aquifer underlies the water table aquifer, and is a localized drinking water supply source. The lower aquifer, confined by a silty clay unit, is flowing artesian and exhibits potentiometric heads of up to 4.5 meters above grade. This high potentiometric head presented a strong possibility that unloading due to excavation would result in a ''blowout'', particularly in areas where the confining unit was < 1 meter thick. Excavation of contaminated materials w as required down to the surface of the confining unit, potentially resulting in an artesian aquifer head of greater than 8 meters above the excavation surface. Consequently, it was determined that a dual-aquifer dewatering system would be required to permit excavation of contaminated material, with the water table aquifer dewatered to facilitate excavation, and the deep aquifer depressurized to prevent a ''blowout''. An additional concern was the potential for vertical migration of contamination present in the water table aquifer that could result from a vertical gradient reversal caused by excessive pumping in the confined system. With these considerations in mind, a conceptual dewatering plan was developed with three major goals: (1) dewater the water table aquifer to control radionuclide migration and allow excavation to proceed; (2) depressurize the lower, artesian aquifer to reduce the potential for a ''blowout''; and (3) develop a precise dewatering level control mechanism to insure a vertical gradient reversal did not result in cross-contamination. The plan was executed through a hydrogeologic investigation culminating with the design and implementation of a complex, multi-phased dual-aquifer dewatering system equipped with a state of the art monitoring network.

  14. Influence of nanoparticles on the polymer-conditioned dewatering of wastewater sludges.

    PubMed

    Boyle, N J; Evans, G M

    2013-01-01

    The effect of using small-scale, high surface area, nanoparticles to supplement polymer-conditioned wastewater sludge dewatering was investigated. Aerobically digested sludge and waste activated sludge sourced from the Hunter Valley, NSW, Australia, were tested with titanium dioxide nanoparticles. The sludge samples were dosed with the nanoparticles in an attempt to adsorb a component of the charged biopolymer surfactants present naturally in sludge. The sludge was conditioned with a cationic polymer. The dewatering characteristics were assessed by measuring the specific resistance to filtration through a modified time-to-filter testing apparatus. The solids content of the dosed samples was determined by a mass balance and compared to the original solids content in the activated sludge. Test results indicated that nanoparticle addition modified the structure of the sludge and provided benefits in terms of the dewatering rate. The samples dosed with nanoparticles exhibited faster water removal, indicating a more permeable filter cake and hence more permeable sludge. A concentration of 2-4% nanoparticles was required to achieve a noticeable benefit. As a comparison, the sludge samples were also tested with a larger particle size, powdered activated carbon (PAC). It was found that the PAC did provide some minor benefits to sludge dewatering but was outperformed by the nanoparticles. The solids content of the final sludge was increased by a maximum of up to 0.6%. The impact of the order sequence of particles and polymer was also investigated. It was found that nanoparticles added before polymer addition provided the best dewatering performance. This outcome was consistent with current theories and previous research through the literature. An economic analysis was undertaken to confirm the viability of the technology for implementation at a full-scale plant. It was found that, currently, this technology is unlikely to be favourable unless the nanoparticles can be sourced for a low cost. PMID:23656957

  15. Field Demonstration of the Performance of a Geotube® Dewatering System to Reduce Phosphorus and Other Substances from Dairy Lagoon Effluent 

    E-print Network

    Mukhtar, Saqib; Wagner, Kevin; Gregory, Lucas

    2009-01-01

    tubes were installed on a 6 millimeter impermeable polyethylene sheet next to a primarily dairy lagoon that received flushed manure. After the tubes were filled, they were allowed to dewater for a period of 6 months. Rainwater typically sheds off...

  16. Synthesis, characterization, and secondary sludge dewatering performance of a novel combined silicon-aluminum-iron-starch flocculant.

    PubMed

    Lin, Qintie; Peng, Huanlong; Zhong, Songxiong; Xiang, Jiangxin

    2015-03-21

    Flocculation is one of the most widely used cost-effective pretreatment method for sludge dewatering, and a novel environmentally friendly and efficient flocculant is highly desired in the sludge dewatering field. In this study, a novel combined silicon-aluminum-ferric-starch was synthesized by grafting silicon, aluminum, and iron onto a starch backbone. The synthesized starch flocculant was characterized using Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy, X-ray powder diffraction, and thermogravimetric analysis. The dewatering performance of secondary sludge was evaluated according to the capillary suction time, settling volume percentage, and specific resistance to filtration. The results indicated that the copolymer exhibited: (1) a good dewatering efficiency over a wide pH range of 3.0-11.0, (2) superior sludge dewatering performance compared to those of polyaluminum chloride (PACl), polyacrylamide (PAM), ferric chloride, and (3) a discontinuous surface with many channels or voids that helps to mobilize the impermeable thin layer of secondary sludge during filter pressing. Such a novel copolymer is a promising green flocculant for secondary sludge dewatering applications. PMID:25497034

  17. Helminth eggs inactivation efficiency by faecal sludge dewatering and co-composting in tropical climates.

    PubMed

    Koné, Doulaye; Cofie, Olufunke; Zurbrügg, Christian; Gallizzi, Katharina; Moser, Daya; Drescher, Silke; Strauss, Martin

    2007-11-01

    This study investigates helminth eggs removal and inactivation efficiency in a treatment process combining faecal sludge (FS) dewatering and subsequent co-composting with organic solid waste as a function of windrow turning frequency. Fresh public toilet sludge and septage mixed at a 1:2 ratio were dewatered on a drying bed. Biosolids with initial loads of 25-83 helminth eggs/g total solids (TS) were mixed with solid waste as bulking material for co-composting at a 1:2 volume ratio. Two replicate sets of compost heaps were mounted in parallel and turned at different frequencies during the active composting period: (i) once every 3 days and (ii) once every 10 days. Turning frequency had no effect on helminth eggs removal efficiency. In both setups, helminth eggs were reduced to <1 viable egg/g TS, thereby complying with the WHO guidelines 2006 for the safe reuse of FS. PMID:17624391

  18. Method for simultaneous use of a single additive for coal flotation, dewatering, and reconstitution

    DOEpatents

    Wen, Wu-Wey (Murrysville, PA); Gray, McMahan L. (Pittsburgh, PA); Champagne, Kenneth J. (Finleyville, PA)

    1995-01-01

    A single dose of additive contributes to three consecutive fine coal unit operations, i.e., flotation, dewatering and reconstitution, whereby the fine coal is first combined with water in a predetermined proportion so as to formulate a slurry. The slurry is then mixed with a heavy hydrocarbon-based emulsion in a second predetermined proportion and at a first predetermined mixing speed and for a predetermined period of time. The conditioned slurry is then cleaned by a froth flotation method to form a clean coal froth and then the froth is dewatered by vacuum filtration or a centrifugation process to form reconstituted products that are dried to dust-less clumps prior to combustion.

  19. Review of Design Approaches Applicable to Dewatering Uranium Mill Tailings Disposal Pits

    SciTech Connect

    Gutknecht, P. J.; Gates, T. E.

    1982-03-01

    This report is a review of design approaches in the literature that may be applicable to uranium mill tailings drainage. Tailings dewatering is required in the deep mined-out pits used for wet tailings disposal. Agricultural drainage theory is reviewed because it is seen as the most applicable technology. It is concluded that the standard drain-pipe envelope design criteria should be easily adapted. The differences in dewatering objectives and physical characteristics between agricultural and tailings drainage systems prevent direct technology transfer with respect to drain spacing calculations. Recommendations for further research are based on the drainage features unique to uranium mill tailings. It is recommended that transient solutions be applied to describe liquid movement through saturated and partially saturated tailings. Modeling should be used to evaluate the benefits of drainage design approaches after careful consideration of potential construction problems.

  20. Effects of sludge properties on the thickening and dewatering of waste activated sludge.

    PubMed

    Merlo, Rion P; Trussell, R Shane; Hermanowicz, Slawomir W; Jenkins, David

    2007-11-01

    The thickening and dewatering of waste activated sludge, from a pilot-scale submerged membrane bioreactor and two bench-scale, complete-mix activated sludge reactors (high-shear and low-shear aeration) treating the same municipal primary effluent, were investigated. Solids settling and compaction were measured using the diluted sludge volume index (DSVI) analysis and a batch centrifugation analysis, respectively. Elevated levels of filamentous microorganisms resulted in higher DSVI values and lower centrifuged pellet concentration. Elevated levels of nocardioform bacteria resulted in lower solids float concentrations, and higher colloidal material reduced solids recovery in batch flotation experiments. Sludge filterability, measured as time-to-filter, was shown to be a function of extracelluar polymeric substances and colloidal material, where higher levels of either reduced sludge filterability. Additional research is necessary to confirm these results using full- or demonstration-scale thickening and dewatering units. PMID:18044358

  1. Method for simultaneous use of a single additive for coal flotation, dewatering and reconstitution

    SciTech Connect

    Wen, Wu-Wey; Gray, M.L.; Champagne, K.J.

    1993-11-09

    A single dose of additive contributes to three consecutive fine coal unit operations, i.e., flotation, dewatering and reconstitution, whereby the fine coal is first combined with water in a predetermined proportion so as to formulate a slurry. The slurry is then mixed with a heavy hydrocarbon-based emulsion in a second predetermined proportion and at a first predetermined mixing speed and for a predetermined period of time. The conditioned slurry is then cleaned by a froth flotation method to form a clean coal froth and then the froth is dewatered by vacuum filtration or a centrifugation process to form reconstituted products that are dried to dust-less clumps prior to combustion.

  2. An investigation of operating variables in the fine coal dewatering and briquetting process

    SciTech Connect

    Kan, S.W.; Wilson, J.W.; Dharman, T.

    1998-07-01

    Illinois basin coals contain minerals, including pyrite, which are finely disseminated in micron-size particles. To liberate these mineral matters from the coal matrix, an ultra-fine grinding operation is required, followed by a wet physical cleaning process, such as column flotation. However, the resulting product possesses large surface areas that conventional dewatering techniques cannot perform effectively, and this creates transportation, storage and handling problems at utility plants. To take full advantage of these cleaning technologies, a new dewatering and coal consolidation method must be developed at the downstream end of the deep coal-cleaning process. Following an initial study at the University of Missouri-Rolla (UMR), briquetting was chosen to perform the dual purpose of dewatering and consolidating the fine coal. A bitumen-based emulsion, Orimulsion, proved to be an effective binder and dewatering agent in the briquetting process that assisted in the expulsion of water from the fine coal. This paper describes the investigation aimed at examining the relationships between several controllable operating variables. An experimental matrix was designed to examine a range of operating parameters based on earlier work conducted at the Department of Mining Engineering, University of Missouri-Rolla. A total of 13 experiments were performed using Illinois No. 6 coal samples that had a size fraction of 16 mesh x 0 and a moisture content of 31%. Based on results obtained from previous experiments and because of the complexity of the briquetting process, only two variables, roll speed and the briquetting form pressure, were studied for their influence on moisture content, abrasion resistance and friability of briquettes. Concurring with results from previous work, the curing time of the briquettes formed had a significant impact on the moisture content and friability of the compacted fine coal product. Also, the statistical regression models generated from these results successfully established basic relationships between the operating parameters of roll speed and briquette form pressure.

  3. Electrokinetically enhanced flow and dewatering characteristics of concentrated black coal-water suspensions in pipes

    SciTech Connect

    Rozakeas, P.K.; Snow, R.J.

    1997-07-01

    The transportability and dewatering of coal-water mixtures flowing in a pipe may be enhanced by the application of electrokinetic techniques. Previous experimental work by other workers shows a significant reduction in the wall shear stress, and consequently a decrease in pumping energy requirements for the flow of coal-water mixtures in pipes combined with electrodewatering. In this process the pipe wall acts as the cathode and a centrally aligned tube as the anode. The effects of {open_quote}In-pipe electrodewatering{close_quote} on the flow properties and stability of concentrated coal-water mixtures flowing in various alternative anode-cathode arrangements are presented in this paper. The application of an electrical energy flux at the electrode surface (< 6.1 kW/m{sup 2}) in a dewatering section of pipe (L{sub e}=1m) effectively reduces the pumping energy requirements by as much as one order of magnitude. The stability of flow conditions is investigated in a concentric anode-cathode pipe arrangement consisting of a dewatering and a non-dewatering section (L{sub o}). In this system (L{sub o}/L{sub e}) < 4.0. A microscopic study of dilute coal-water suspensions in the presence of a DC electric field revealed the migration of coal particles towards the anode and the structural formation of coal particle chains. The electrorheological behaviour of concentrated coal-water suspensions is examined with the use of a modified coaxial rheometer. The coal fines (d{sub 50}=17.7{mu}m) used in all experiments were produced by milling a low rank bituminous black coal which was followed by a sieving process that eliminated coal particles that were greater than 75{mu}m in size.

  4. Hydrophobic Dewatering of Fine Coal. Topical report, March 1, 1995-March 31, 1997

    SciTech Connect

    Yoon, R.; Sohn, S.; Luttrell, J.; Phillips, D.

    1997-12-31

    Many advanced fine coal cleaning technologies have been developed in recent years under the auspices of the U.S. Department of Energy. However, they are not as widely deployed in industry as originally anticipated. An important reason for this problem is that the cleaned coal product is difficult to dewater because of the large surface area associated with fine particles. Typically, mechanical dewatering, such as vacuum filtration and centrifugation, can reduce the moisture to 20-35% level, while thermal drying is costly. To address this important industrial problem, Virginia Tech has developed a novel dewatering process, in which water is displaced from the surface of fine particulate materials by liquid butane. Since the process is driven by the hydrophobic interaction between coal and liquid butane, it was referred to as hydrophobic dewatering (HD). A fine coal sample with 21.4 pm median size was subjected to a series of bench-scale HD tests. It was a mid-vol bituminous coal obtained from the Microcel flotation columns operating at the Middle Fork coal preparation plant, Virginia. All of the test results showed that the HD process can reduce the moisture to substantially less than 10%. The process is sensitive to the amount of liquid butane used in the process relative to the solids concentration in the feed stream. Neither the intensity nor the time of agitation is critical for the process. Also, the process does not require long time for phase separation. Under optimal operating conditions, the moisture of the fine coal can be reduced to 1% by weight of coal.

  5. Emplacement and dewatering of the world's largest exposed sand injectite complex

    NASA Astrophysics Data System (ADS)

    Sherry, Timothy J.; Rowe, Christie D.; Kirkpatrick, James D.; Brodsky, Emily E.

    2012-08-01

    Sandstone injectites form by up or down-section flow of a mobilized sand slurry through fractures in overlying rock. They act as reservoirs and high-permeability conduits through lower permeability rock in hydrocarbon systems. The Yellow Bank Creek Complex, Santa Cruz County, California is the largest known exposure of a sandstone injectite in the world. The complex contains granular textures that record processes of sand slurry flow, multiple pore fluids, and dewatering after emplacement. The injection was initially mobilized from a source containing both water and hydrocarbons. The water-sand slurry reached emplacement depth first, due to lower fluid viscosity. As the sand slurry emplaced, the transition from slurry flow to pore water percolation occurred. This transition resulted in preferred flow channels ˜6 mm wide in which sand grains were weakly aligned (laminae). The hydrocarbon-sand slurry intruded the dewatering sands and locally deformed the laminae. Compaction of the injectite deposit and pore fluid escape caused spaced compaction bands and dewatering pipes which created convolutions of the laminae. The hydrocarbon-rich sand slurry is preserved today as dolomite-cemented sand with oil inclusions. The laminae in this injectite are easily detected due to preferential iron oxide-cementation of the well-aligned sand laminae, and lack of cement in the alternating laminae. Subtle textures like these may develop during sand flow and be present but difficult to detect in other settings. They may explain permeability anisotropy in other sand deposits.

  6. Model analysis of effects on water levels at Indiana Dunes National Lakeshore caused by construction dewatering

    USGS Publications Warehouse

    Marie, James R.

    1976-01-01

    The computer models were developed to investigate possible hydrologic effects within the Indiana Dunes National Lakeshore caused by planned dewatering at the adjacent Bailly Nuclear Generator construction site. The model analysis indicated that the planned dewatering would cause a drawdown of about 4 ft under the westernmost pond of the Lakeshore and that this drawdown would cause the pond to go almost dry--less than 0.5 ft of water remaining in about 1 percent of the pond--under average conditions during the 18-month dewatering period. When water levels are below average, as during late July and early August 1974, the pond would go dry in about 5.5 months. However, the pond may not have to go completely dry to damage the ecosystem. If the National Park Service 's independent study determines the minimum pond level at which ecosystem damage would be minimized, the models developed in this study could be used to predict the hydrologic conditions necessary to maintain that level. (Woodard-USGS)

  7. Efficient Calculation of Dewatered and Entrapped Areas Using Hydrodynamic Modeling and GIS

    SciTech Connect

    Richmond, Marshall C.; Perkins, William A.

    2009-12-01

    River waters downstream of a hydroelectric project are often subject to rapidly changing discharge. Abrupt decreases in discharge can quickly dewater and expose some areas and isolate other areas from the main river channel, potentially stranding or entrapping fish, which often results in mortality. A methodology is described to estimate the areas dewatered or entrapped by a specific reduction in upstream discharge. A one-dimensional hydrodynamic model was used to simulate steady flows. Using flow simulation results from the model and a geographic information system (GIS), estimates of dewatered and entrapped areas were made for a wide discharge range. The methodology was applied to the Hanford Reach of the Columbia River in central Washington State. Results showed that a 280 m$^3$/s discharge reduction affected the most area at discharges less than 3400 m$^3$/s. At flows above 3400 m$^3$/s, the affected area by a 280 m$^3$/s discharge reduction (about 25 ha) was relatively constant. A 280 m$^3$/s discharge reduction at lower flows affected about twice as much area. The methodology and resulting area estimates were, at the time of writing, being used to identify discharge regimes, and associated water surface elevations, that might be expected to minimize adverse impacts on juvenile fall chinook salmon (\\emph{Oncorhynchus tshawytscha}) that rear in the shallow near-shore areas in the Hanford Reach.

  8. Bioflocculant from pre-treated sludge and its applications in sludge dewatering and swine wastewater pretreatment.

    PubMed

    Guo, Junyuan; Ma, Jing

    2015-11-01

    Potentials of alkaline-thermal (ALT) pre-treated sludge as a bioflocculant were studied in sludge dewatering and swine wastewater pretreatment. When incubated with this ALT pre-treated sludge, dry solids (DS) and specific resistance to filtration (SRF) of typical wastewater activated sludge reached 22.5% and 3.4×10(12)m/kg, respectively, which were much better than that obtained with conventional chemical flocculants. Sludge dewatering was further improved when both the bioflocculant and conventional polyaluminum chloride (PAC) were used simultaneously. Charge neutralization and inter-particle bridging were proposed as the reasons for the enhanced performance in the case of the combined use. With swine wastewater, the bioflocculant could remove COD, ammonium and turbidity by 45.2%, 41.8% and 74.6% when incubated with 20mg/L at pH 8.0. This study suggested that the ALT pre-treated sludge has a great potential as an alternative bioflocculant to conventional flocculants in sludge dewatering and swine wastewater pretreatment. PMID:26259686

  9. Demonstration of FBRM as process analytical technology tool for dewatering processes via CST correlation.

    PubMed

    Cobbledick, Jeffrey; Nguyen, Alexander; Latulippe, David R

    2014-07-01

    The current challenges associated with the design and operation of net-energy positive wastewater treatment plants demand sophisticated approaches for the monitoring of polymer-induced flocculation. In anaerobic digestion (AD) processes, the dewaterability of the sludge is typically assessed from off-line lab-bench tests - the capillary suction time (CST) test is one of the most common. Focused beam reflectance measurement (FBRM) is a promising technique for real-time monitoring of critical performance attributes in large scale processes and is ideally suited for dewatering applications. The flocculation performance of twenty-four cationic polymers, that spanned a range of polymer size and charge properties, was measured using both the FBRM and CST tests. Analysis of the data revealed a decreasing monotonic trend; the samples that had the highest percent removal of particles less than 50 microns in size as determined by FBRM had the lowest CST values. A subset of the best performing polymers was used to evaluate the effects of dosage amount and digestate sources on dewatering performance. The results from this work show that FBRM is a powerful tool that can be used for optimization and on-line monitoring of dewatering processes. PMID:24751547

  10. Dewatering: Coal and mineral processing. January 1970-March 1990 (A Bibliography from the COMPENDEX data base). Report for January 1970-March 1990

    SciTech Connect

    Not Available

    1990-05-01

    This bibliography contains citations concerning the technology of dewatering. Included is coverage of techniques, processes, and evaluations applied to coal processing, coal slurry preparation, ash treatments, and processing of other mineral ores. Mechanical devices, heating devices, filtering techniques, air drying, the use of surfactants and flocculants, and design techniques in dewatering systems are discussed. Dewatering of peats, sewage sludges, and industrial sludges are referenced in related published bibliographies. (Contains 173 citations fully indexed and including a title list.)

  11. Hydrothermal treatment coupled with mechanical expression at increased temperature for excess sludge dewatering: the dewatering performance and the characteristics of products.

    PubMed

    Wang, Liping; Li, Aimin

    2015-01-01

    Hydrothermal treatment coupled with mechanical expression at increased temperature in two separate cells respectively is effective for the dewatering of excess sludge with low energy consumption. The objectives of this study were to evaluate the dewatering performance and the characteristics of obtained products (hydrothermal sludge, hydrochar and filtrate). The results showed that harsher hydrothermal treatment (temperature from 120 to 210 °C and residence time from 10 to 90 min) led to greater water removal (from 7.44 to 96.64% reduction of total water) and mechanical pressure became less significant as it increased. The whole expression stage was completely described by the modified Terzaghi-Voigt rheological model. The role of tertiary consolidation stage in the water removal was reduced with hydrothermal treatment being stronger. The hydrothermal treatment is mainly a devolatilization process. The observed changes in H/C and O/C for hydrothermal sludge suggested dehydration was the major reaction mechanism and decarboxylation only occurred significantly at higher temperature. The higher heating value correlated well with carbon content of sludge, which was increased by 4.8% for hydrothermal sludge at 210 °C for 60 min and significantly decreased by 15.4% for hydrochar after 6.0 MPa for 20 min. The solubilization and decomposition of proteins, polysaccharides and DNA were determined to be temperature and residence time dependent. The improvement of dewaterability was closely correlated to the variation of these biopolymers. The filtrates collected above 150 °C were found to be acidic. The increase of humic substances and the melanoidins formed by Maillard reaction were largely responsible for the filtrate color. PMID:25462737

  12. Effects of Cationic Polyacrylamide Characteristics on Sewage Sludge Dewatering and Moisture Evaporation

    PubMed Central

    Pan, Chengyi

    2014-01-01

    The effects of the molecular weight (MW) and charge density (CD) of cationic polyacrylamide (CPAM) on sludge dewatering and moisture evaporation were investigated in this study. Results indicated that in sludge conditioning, the optimum dosages were 10, 6, 6, 4, and 4 mg g?1 CPAM with 5 million MW and 20% CD, 5 million MW and 40% CD, 3 million MW and 40% CD, 8 million MW and 40% CD, and 5 million MW and 60% CD, respectively. The optimum dosage of CPAM was negatively correlated with its CD or MW if the CD or MW of CPAM was above 20% or 5 million. In the centrifugal dewatering of sludge, the moisture content in the conditioned sludge gradually decreased with the extension of centrifugation time, and the economical centrifugal force was 400×g. The moisture evaporation rates of the conditioned sludge were closely related to sludge dewaterability, which was in turn significantly correlated either positively with the solid content of sludge particles that were >2 mm in size or negatively with that of particles measuring 1 mm to 2 mm in diameter. During treatment, sludge moisture content was reduced from 80% to 20% by evaporation, and the moisture evaporation rates were 1.35, 1.49, 1.62, and 2.24 times faster in the sludge conditioned using 4 mg g?1 CPAM with 5 million MW and 60% CD than in the sludge conditioned using 4 mg g?1 CPAM with 8 million MW and 40% CD, 6 mg g?1 CPAM with 5 million MW and 40% CD, 6 mg g?1 CPAM with 3 million MW and 40% CD, and 10 mg g?1 CPAM with 5 million MW and 20% CD, respectively. Hence, the CPAM with 5 million MW and 60% CD was ideal for sludge dewatering. PMID:24878582

  13. Dewatering studies of fine clean coal. Final technical report, September 1, 1991--August 31, 1992

    SciTech Connect

    Parekh, B.K.

    1992-12-31

    Physical cleaning of ultra-fine coal using advanced froth flotation technique provides a low ash product; however, the amount of water associated with clean coal is high. Economic removal of water from the froth will be important for commercial applicability of the advanced flotation processes. The main objective of the present research program is to study and understand dewatering characteristics of ultra-fine clean coal and to develop process parameters to effectively reduce the moisture to less than 20 percent in the clean coal product. The research approach utilized synergistic effect of metal ions and surfactant addition to lower the moisture of clean coal using the conventional vacuum dewatering technique. The studies have identified a combinations of metal ions and surfactants in providing a 22 percent moisture filter cake. Surface chemical study indicated a direct correlation between the point-of-zero charge (PZC) of metal ion/fine coal system and lowering of moisture in the filter cake. Adsorption of either metal ions or surfactants alone did not provide a significant reduction of moisture in the filter cake. However, a combination of the two provided a filter cake containing about 22 percent moisture. Filtration tests conducted using a laboratory vacuum drum filter indicated that the results obtained in batch filtration could be reproduced on a continuous filtration unit. FT-IR studies indicated that anionic surfactant and metal ions form complex species which adsorbs on the fine coal and results in improved moisture reduction during filtration. Recommendations are offered for testing this novel dewatering process on a pilot scale at a coal preparation plant in Illinois.

  14. Textural evidence for jamming and dewatering of a sub-surface, fluid-saturated granular flow

    NASA Astrophysics Data System (ADS)

    Sherry, T. J.; Rowe, C. D.; Kirkpatrick, J. D.; Brodsky, E. E.

    2011-12-01

    Sand injectites are spectacular examples of large-scale granular flows involving migration of hundreds of cubic meters of sand slurry over hundreds of meters to kilometers in the sub-surface. By studying the macro- and microstructural textures of a kilometer-scale sand injectite, we interpret the fluid flow regimes during emplacement and define the timing of formation of specific textures in the injected material. Fluidized sand sourced from the Santa Margarita Fm., was injected upward into the Santa Cruz Mudstone, Santa Cruz County, California. The sand injectite exposed at Yellow Bank Beach records emplacement of both hydrocarbon and aqueous sand slurries. Elongate, angular mudstone clasts were ripped from the wall rock during sand migration, providing evidence for high velocity, turbid flow. However, clast long axis orientations are consistently sub-horizontal suggesting the slurry transitioned to a laminar flow as the flow velocity decreased in the sill-like intrusion. Millimeter to centimeter scale laminations are ubiquitous throughout the sand body and are locally parallel to the mudstone clast long axes. The laminations are distinct in exposure because alternating layers are preferentially cemented with limonite sourced from later groundwater infiltration. Quantitative microstructural analyses show that the laminations are defined by subtle oscillations in grain alignment between limonite and non-limonite stained layers. Grain packing, size and shape distributions do not vary. The presence of limonite in alternating layers results from differential infiltration of groundwater, indicating permeability changes between the layers despite minimal grain scale differences. Convolute dewatering structures deform the laminations. Dolomite-cemented sand, a signature of hydrocarbon saturation, forms irregular bodies that cross-cut the laminations and dewatering structures. Laminations are not formed in the dolomite-cemented sand. The relative viscosity difference between the hydrocarbon and aqueous sand slurries controls the the critical radius of the contacts between dolomite cemented and limonite cemented sand bodies. The cross-cutting relationships established in the field show that the laminations formed at the jamming transition in the aqueous sand slurry. We interpret the laminations as preserving evidence for dynamic permeability instabilities in the dewatering slurry. Relatively high permeability channels formed as pore fluid flow rearranged grains during initial dewatering. Once initiated, the flow localized further into the higher permeability channels resulting in a feedback that caused the permeability in the channels to increase.

  15. Sludge dewatering: Sewage and industrial wastes. January 1978-December 1989 (A Bibliography from Pollution Abstracts). Report for January 1978-December 1989

    SciTech Connect

    Not Available

    1990-03-01

    This bibliography contains citations concerning techniques and equipment used in sewage, as well as industrial, mining, petroleum, and municipal-waste sludge dewatering. Dewatering processes, device design, and performance evaluations are considered. (This updated bibliography contains 266 citations, 12 of which are new entries to the previous edition.)

  16. Bioelectrochemical desalination and electricity generation in microbial desalination cell with dewatered sludge as fuel.

    PubMed

    Meng, Fanyu; Jiang, Junqiu; Zhao, Qingliang; Wang, Kun; Zhang, Guodong; Fan, Qingxin; Wei, Liangliang; Ding, Jing; Zheng, Zhen

    2014-04-01

    Microbial desalination cells (MDCs) with common liquid anodic substrate exhibit a slow startup and destructive pH drop, and abiotic cathodes have high cost and low sustainability. A biocathode MDC with dewatered sludge as fuel was developed for synergistic desalination, electricity generation and sludge stabilization. Experimental results indicated that the startup period was reduced to 3d, anodic pH was maintained between 6.6 and 7.6, and high stability was shown under long-term operation (300d). When initial NaCl concentrations were 5 and 10g/L, the desalinization rates during stable operation were 46.37±1.14% and 40.74±0.89%, respectively. The maximum power output of 3.178W/m(3) with open circuit voltage (OCV) of 1.118V was produced on 130d. After 300d, 25.71±0.15% of organic matter was removed. These results demonstrated that dewatered sludge was an appropriate anodic substrate to enhance MDC stability for desalination and electricity generation. PMID:24534793

  17. Characterization of a bioflocculant from potato starch wastewater and its application in sludge dewatering.

    PubMed

    Guo, Junyuan; Zhang, Yuzhe; Zhao, Jing; Zhang, Yu; Xiao, Xiao; Wang, Bin; Shu, Bi

    2015-07-01

    A bioflocculant was produced by using potato starch wastewater; its potential in sludge dewatering and potato starch wastewater treatment was investigated. Production of this bioflocculant was positively associated with cell growth, and a highest value of 0.81 g/L was obtained. When incubated with this bioflocculant, dry solids (DS) and specific resistance to filtration (SRF) of typical wastewater activated sludge reached 20.8% and 3.9?×?10(12) m/kg, respectively, which were much better than the ones obtained with conventional chemical flocculants. Sludge dewatering was further improved when both the bioflocculant and conventional polyacrylamide (PAM) were used simultaneously. With potato starch wastewater, chemical oxygen demand (COD) and turbidity removal rates could reach 52.4 and 81.7%, respectively, at pH value of 7.5 when the bioflocculant dose was adjusted to 30 mg/L; from a practical standpoint, the removal of COD and turbidity reached 48.3 and 72.5%, respectively, without pH value adjustment. PMID:25851719

  18. Chitosan use in chemical conditioning for dewatering municipal-activated sludge.

    PubMed

    Zemmouri, H; Mameri, N; Lounici, H

    2015-01-01

    This work aims to evaluate the potential use of chitosan as an eco-friendly flocculant in chemical conditioning of municipal-activated sludge. Chitosan effectiveness was compared with synthetic cationic polyelectrolyte Sedipur CF802 (Sed CF802) and ferric chloride (FeCl?). In this context, raw sludge samples from Beni-Messous wastewater treatment plant (WWTP) were tested. The classic jar test method was used to condition sludge samples. Capillary suction time (CST), specific resistance to filtration (SRF), cakes dry solid content and filtrate turbidity were analyzed to determine filterability, dewatering capacity of conditioned sludge and the optimum dose of each conditioner. Data exhibit that chitosan, FeCl?and Sed CF802 improve sludge dewatering. Optimum dosages of chitosan, Sed CF802 and FeCl?allowing CST values of 6, 5 and 9 s, were found, respectively, between 2-3, 1.5-3 and 6 kg/t ds. Both polymers have shown faster water removal with more permeable sludge. SRF values were 0.634 × 10¹², 0.932 × 10¹² and 2 × 10¹² m/kg for Sed CF802, chitosan and FeCl?respectively. A reduction of 94.68 and 87.85% of the filtrate turbidity was obtained with optimal dosage of chitosan and Sed CF802, respectively. In contrast, 54.18% of turbidity abatement has been obtained using optimal dosage of FeCl?. PMID:25812088

  19. Rapid dewatering of the crust deduced from ages of mesothermal gold deposits

    USGS Publications Warehouse

    Goldfarb, R.J.; Snee, L.W.; Miller, L.D.; Newberry, R.J.

    1991-01-01

    The large-scale migration of fluids through the continental crust has been well documented, but there is no consensus regarding the timing of fluid migration relative to erogenic episodes, or rates of crustal dewatering1. Here we present 40Ar/39Ar dates for muscovites from quartz veins along a major shear zone in southeast Alaska, which show that the veins were emplaced in the early Eocene, during the late stages of orogenic deformation. Hydrothermal activity took place for only about 1 Myr and along a distance of at least 200 km. The fluids were generated by metamorphic reactions in subducted crust along the North American plate margin, and were apparently trapped in the crust by the low permeabilities accompanying a convergent tectonic regime until 56 Myr ago. The rapid dewatering event coincided with a change in plate motion at 56-55 Myr, which caused a shift from convergent to partly transcurrent tectonics. We suggest that this change in tectonic regime led to increased crustal permeabilities and hence the possibility of large-scale fluid migration.

  20. Isolation and Characterization of Polyacrylamide-Degrading Bacteria from Dewatered Sludge

    PubMed Central

    Yu, Feng; Fu, Ruimin; Xie, Yun; Chen, Wuling

    2015-01-01

    Polyacrylamide (PAM) is a water-soluble polymer that is widely used as a flocculant in sewage treatment. The accumulation of PAM affects the formation of dewatered sludge and potentially produces hazardous monomers. In the present study, the bacterial strain HI47 was isolated from dewatered sludge. This strain could metabolize PAM as its sole nutrient source and was subsequently identified as Pseudomonas putida. The efficiency of PAM degradation was 31.1% in 7 days and exceeded 45% under optimum culture condition (pH 7.2, 39 °C and 100 rpm). The addition of yeast extract and glucose improved the bacterial growth and PAM degradation. The degraded PAM samples were analyzed by gel-filtration chromatography, Fourier transform infrared and high-performance liquid chromatography. The results showed that high-molecular-weight PAM was partly cleaved to small molecular oligomer derivatives and part of the amide groups of PAM had been converted to carboxyl groups. The biodegradation did not accumulate acrylamide monomers. Based on the SDS-PAGE and N-terminal sequencing results, the PAM amide groups were converted into carboxyl groups by a PAM-induced extracellular enzyme from the aliphatic amidase family. PMID:25893998

  1. Occurrence and Fate of Trace Contaminants during Aerobic and Anaerobic Sludge Digestion and Dewatering.

    PubMed

    Guerra, Paula; Kleywegt, Sonya; Payne, Michael; Svoboda, M Lewina; Lee, Hing-Biu; Reiner, Eric; Kolic, Terry; Metcalfe, Chris; Smyth, Shirley Anne

    2015-07-01

    Digestion of municipal wastewater biosolids is a necessary prerequisite to their beneficial use in land application, in order to protect public health and the receiving environment. In this study, 13 pharmaceuticals and personal care products (PPCPs), 11 musks, and 17 polybrominated diphenyl ethers were analyzed in 84 samples including primary sludge, waste activated sludge, digested biosolids, dewatered biosolids, and dewatering centrate or filtrate collected from five wastewater treatment plants with aerobic or anaerobic digestion. Aerobic digestion processes were sampled during both warm and cold temperatures to analyze seasonal differences. Among the studied compounds, triclosan, triclocarban, galaxolide, and BDE-209 were the substances most frequently detected under different treatment processes at levels up to 30,000 ng/g dry weight. Comparing aerobic and anaerobic digestion, it was observed that the levels of certain PPCPs and musks were significantly higher in anaerobically digested biosolids, relative to the residues from aerobic digestion. Therefore, aerobic digestion has the potential advantage of reducing levels of PPCPs and musks. On the other hand, anaerobic digestion has the advantage of recovering energy from the biosolids in the form of combustible gases while retaining the nutrient and soil conditioning value of this resource. PMID:26437100

  2. Bioelectrochemically-assisted anaerobic composting process enhancing compost maturity of dewatered sludge with synchronous electricity generation.

    PubMed

    Yu, Hang; Jiang, Junqiu; Zhao, Qingliang; Wang, Kun; Zhang, Yunshu; Zheng, Zhen; Hao, Xiaodi

    2015-10-01

    Bioelectrochemically-assisted anaerobic composting process (AnCBE) with dewatered sludge as the anode fuel was constructed to accelerate composting of dewatered sludge, which could increase the quality of the compost and harvest electric energy in comparison with the traditional anaerobic composting (AnC). Results revealed that the AnCBE yielded a voltage of 0.60 ± 0.02 V, and total COD (TCOD) removal reached 19.8 ± 0.2% at the end of 35 d. The maximum power density was 5.6 W/m(3). At the end of composting, organic matter content (OM) reduction rate increased to 19.5 ± 0.2% in AnCBE and to 12.9 ± 0.1% in AnC. The fuzzy comprehensive assessment (FCA) result indicated that the membership degree of class I of AnCBE compost (0.64) was higher than that of AnC compost (0.44). It was demonstrated that electrogenesis in the AnCBE could improve the sludge stabilization degree, accelerate anaerobic composting process and enhance composting maturity with bioelectricity generation. PMID:26115526

  3. Enhanced sludge conditioning by enzyme pre-treatment: comparison of laboratory and pilot scale dewatering results.

    PubMed

    Dursun, D; Turkmen, M; Abu-Orf, M; Dentel, S K

    2006-01-01

    The effect of enzyme pre-treatment on dewaterability of anaerobically digested sludge was investigated at both laboratory and pilot scale. Our results revealed a significant increase in cake solid content (27% cake solids compared to 18% without enzyme pre-treatment), using an enzyme dose of only 20 mg/L. In order to assess practical application, enzyme pre-treatment was applied at the Wilmington, Delaware (U.S.) wastewater treatment plant, using a pilot-scale centrifuge. However, the efficiency reached in laboratory scale could not be obtained in pilot scale, where the final cake solids content did not exceed 20%. Centrifuge and belt filter press (simulated by Crown Press) dewatering were compared in terms of the process efficiencies in the absence and presence of enzyme pre-treatment. Possible factors that might cause the differences were tested by experimental and statistical comparisons. Results indicated that the higher shear applied in centrifugation is responsible for the lack of improved cake solids. The network strength of sludge determined by rheological measurements revealed that enzymatic treatment weakens the gel structure of the sludge floc through the hydrolysis of extracellular polymeric substances; this allows improved dewatering by filtration processes, but leads to floc deterioration when subjected to high shear during centrifugation. PMID:17087367

  4. Bacterial pathogen indicators regrowth and reduced sulphur compounds' emissions during storage of electro-dewatered biosolids.

    PubMed

    Navab-Daneshmand, Tala; Enayet, Samia; Gehr, Ronald; Frigon, Dominic

    2014-10-01

    Electro-dewatering (ED) increases biosolids dryness from 10-15 to 30-50%, which helps wastewater treatment facilities control disposal costs. Previous work showed that high temperatures due to Joule heating during ED inactivate total coliforms to meet USEPA Class A biosolids requirements. This allows biosolids land application if the requirements are still met after the storage period between production and application. In this study, we examined bacterial regrowth and odour emissions during the storage of ED biosolids. No regrowth of total coliforms was observed in ED biosolids over 7d under aerobic or anaerobic incubations. To mimic on-site contamination during storage or transport, ED samples were seeded with untreated sludge. Total coliform counts decreased to detection limits after 4d in inoculated samples. Olfactometric analysis of ED biosolids odours showed that odour concentrations were lower compared to the untreated and heat-treated control biosolids. Furthermore, under anaerobic conditions, odorous reduced sulphur compounds (methanethiol, dimethyl sulphide and dimethyl disulphide) were produced by untreated and heat-treated biosolids, but were not detected in the headspaces above ED samples. The data demonstrate that ED provides advantages not only as a dewatering technique, but also for producing biosolids with lower microbial counts and odour levels. PMID:25065797

  5. Evaluation of hyperbaric filtration for fine coal dewatering. Fifth quarterly technical progress report, October 1, 1993--December 31, 1993

    SciTech Connect

    Parekh, B.K.; Hogg, R.; Fonseca, A.

    1993-12-31

    The main objectives of the project are to investigate the fundamental aspects of particle-liquid interaction in fine coal dewatering, to conduct laboratory and pilot plant studies on the applicability of hyperbaric filter systems and to develop process conditions for dewatering of fine clean coal to less than 20 percent moisture. The program consist of three phases: model development; laboratory studies; and field testing. The Pennsylvania State University is leading efforts in Phase I, the University of Kentucky in Phase II, and Consol Inc. in Phase III of the program. All three organizations are involved in all the three phases of the program. The Pennsylvania State University is developing a theoretical model for hyperbaric filtration systems, whereas the University of Kentucky is conducting experimental studies to investigate fundamental aspects of particle-liquid interaction and application of high pressure filter in fine coal dewatering. The optimum filtration conditions identified in phase I and 11 will be tested in a Consol Inc. coal preparation plant using an Andritz Ruthner portable hyperbaric filtration unit. In this report, dewatering model development and laboratory studies are presented.

  6. Reducing the moisture content of clean coals. Volume 4, Aiding the dewatering and classifying of fine coal with an ultrasonic tray: Final report

    SciTech Connect

    Raleigh, C.E.

    1992-11-01

    Volume four contains the results of an Empire State Electric Energy Research corporation and Electric Power Research Institute (EPRI) funded investigation to evaluate the effects and economics of applying ultrasonic waves to commercial-scale dewatering and classifying of fine coal. Pre-treating minus 28 mesh Upper Freeport Seam coal using an ultrasonic tray device improved subsequent dewatering by a vacuum disc filter after thickening in a cyclone, but it did not improve dewatering by a screen-bowl centrifuge after cycloning. Dewatering of Pittsburgh Seam coal also improved when the coal was ultrasonically treated, but it only manifested during thickening in the cyclone. Cycloning also increased the removal of fine, high-ash content clay particles from Pittsburgh Seam coal. In contrast, ultrasonically-treating Upper Freeport Seam coal did not improve subsequent classifying by a rapped sieve bend. Based on a specific example of results in this test work for Upper Freeport Seam coal, using an ultrasonic tray to aid dewatering of finely-sized coal can be economically beneficial. For other coals and dewatering devices, however, the economics for using ultrasonic trays to enhance fine coal dewatering will differ.

  7. A study of a solvent/binder combination for viscosity reduction of Orimulsion in fine coal dewatering

    SciTech Connect

    Kan, S.W.; Wilson, J.W.; Dharman, T.; Aksoy, B.S.

    1998-07-01

    To effectively liberate finely disseminated minerals from a coal matrix, a pulverization operation is needed. In this process fine coal particles are formed that possess large surface areas that are difficult to dewater, and create transportation, storage and handling problems at coal cleaning and utility plants. Using both laboratory and pilot scale models, research work conducted at the Department of Mining Engineering at University of Missouri-Rolla (UMR) on a single-state fine coal dewatering and briquetting technique, has shown the potential of briquetting to enhance the handling, transportation, and storage of fine coal. The operation uses a hydrophobic binder as the dewatering and briquetting agent and requires a compaction device, specifically, a commercial-scale briquetting machine. In the single-state dewatering-briquetting process, a bitumen-in-water emulsion (Orimulsion), which has high viscosity even at room temperature, was selected as the binder. Due to the tacky nature of the binder, it was felt that by reducing its viscosity using a solvent, the binder could more effectively coat the fine coal surfaces. This study investigated the efficiency of a solvent/binder combination for reducing the viscosity of the Orimulsion for the dewatering of fine coal, and making robust briquettes from predominantly -400 mesh coal particles. Preliminary results indicated that by adding a solvent to the binder, it reduced the viscosity of the Orimulsion, which in turn provided a more efficient use of the binder and resulted in a better coating of the ultra-fine coal particles. Using multiple-variable linear regression analyses, it was possible to establish basic relationships between the change in moisture of coal pellets and several operating variables. The model showed that the compaction pressure, as well as the type and amount of solvent used in conjunction with Orimulsion, influenced the moisture content of the coal pellets produced.

  8. Hydrothermal treatment coupled with mechanical expression at increased temperature for excess sludge dewatering: influence of operating conditions and the process energetics.

    PubMed

    Wang, Liping; Zhang, Lei; Li, Aimin

    2014-11-15

    Dewatering is very important for excess sludge treatment and disposal. Hydrothermal treatment coupled with mechanical expression is a novel technology, in which a conventional pressure dewatering is combined with hydrothermal effect to realize an improved liquid/solids separation with low energy consumption. In this study, the process was performed by way of that the excess sludge was hydrothermally treated first and then the mechanical expression was employed immediately at increased temperature in two separate cells respectively. The results demonstrated that the mechanical expression employed at increased temperature showed a significant advantage than that at room temperature, given a further reduction of 19-47% of the moisture content. The dewatering process at room temperature was mostly depended on the effect of mechanical expression. Hydrothermal process, more importantly than mechanical effect at increased temperatures, seemed to govern the extent to which the dewatering process occurred. The dewatering began to show a positive effect when the temperature was exceeded the threshold temperature (between 120 and 150 °C). The residence time of 30 min promoted a substantial conversion in the sludge surface properties. After dewatering at temperatures of 180-210 °C, the moisture content decreased from 52 to 20% and the corresponding total water removal as filtrate was between 81 and 93%. It was observed that the moisture content of filter cake correlated with surface charge (Rp = -0.93, p < 0.05) and relative hydrophobicity (Rp = -0.99, p < 0.05). The calculated energy balance suggested that no additional external energy input is needed to support the dewatering process for excess sludge. The dewatering process needs an obviously lower energy input compared to thermal drying and electro-dewatering to produce a higher solids content cake. PMID:25090626

  9. POC-scale testing of an advanced fine coal dewatering equipment/technique. Quarterly technical progress report 6, January--March 1996

    SciTech Connect

    Tao, D.; Groppo, J.G.; Parekh, B.K.

    1996-05-03

    Froth flotation technique is an effective and efficient process for recovering of ultra-fine clean coal. Economical dewatering of an ultra-fine clean coal product to a 20% level moisture will be an important step in successful implementation of the advanced cleaning processes. This project is a step in the Department of Energy`s program to show that ultra-clean coal could be effectively dewatered to 20% or lower moisture using either conventional or advanced dewatering techniques. The cost-sharing contract effort is for 36 months beginning September 30, 1994. This report discusses technical progress made during the quarter from January 1- March 31, 1996.

  10. Development of the Electroacoustic Dewatering (EAD) process for fine/ultrafine coal: First quarterly progress report, period ending December 15, 1988

    SciTech Connect

    Not Available

    1989-01-05

    Battelle, in cooperation with the Electric Power Research Institute (EPRI), Ashbrook-Simon-Hartley (ASH), Kaiser Engineers (KE), Lewis Corporation, and Prof. S.H. Chiang of the University of Pittsburgh, is developing an advanced process for the dewatering of fine and ultrafine coals. The advanced process, called Electroacoustic Dewatering (EAD), capitalizes on the adaptation of synergistic effects of electric and acoustic fields to a commercial belt filter press design that is used in many other applications. 1 fig.

  11. Insights into the respective role of acidification and oxidation for enhancing anaerobic digested sludge dewatering performance with Fenton process.

    PubMed

    Zhang, Weijun; Yang, Peng; Yang, Xiaoyin; Chen, Zhan; Wang, Dongsheng

    2015-04-01

    Digested sludges generally exhibit poorer dewaterability than activated sludges. This study investigated the effects of acidification and oxidation on EPS properties and dewaterability of anaerobic digested sludge in Fenton treatment in order to unravel the underlying mechanism of sludge conditioning. The results indicated that sludge dewatering property was improved after acidification treatment. Meanwhile, fluorescence analysis revealed that the protein-like substances were effectively removed from sludge bulk after acidification treatment. Acidification and Fenton oxidation showed a significant synergetic effect in enhancing sludge dewatering process. Solubilization and decomposition of bound EPS occurred synchronously during Fenton conditioning. Oxidation process is very likely to play a more important role in sludge conditioning than Fenton coagulation. According to pilot test, Fenton treatment performed much better in cake moisture content reduction than chemical conditioning with traditional inorganic coagulants. Additionally, full-scale application of Fenton conditioning will not have detrimental effects on performance of wastewater treatment system. PMID:25656869

  12. Transport phenomena in the crystallization of lysozyme by osmotic dewatering and liquid-liquid diffusion in low gravity

    NASA Technical Reports Server (NTRS)

    Todd, Paul; Sportiello, Michael G.; Gregory, Derek; Cassanto, John M.; Alvarado, Ulises A.; Ostroff, Robert; Korszun, Z. R.

    1993-01-01

    Two methods of protein crystallization, osmotic dewatering and liquid-liquid diffusion, like the vapor diffusion (hanging-drop and sessile-drop) methods allow a gradual approach to supersaturation conditions. The crystallization of hen egg-white lysozyme, an extensively characterized protein crystal, in the presence of sodium chloride was used as an experimental model with which to compare these two methods in low gravity and in the laboratory. Comparisons of crystal growth rates by the two methods under the two conditions have, to date, indicated that the rate of crystal growth by osmotic dewatering is nearly the same in low gravity and on the ground, while much faster crystal growth rates can be achieved by the liquid-liquid diffusion method in low gravity.

  13. Study on the pore structure and oxygen-containing functional groups devoting to the hydrophilic force of dewatered lignite

    NASA Astrophysics Data System (ADS)

    Zhang, Yanli; Jing, Xiaoxia; Jing, Kaige; Chang, Liping; Bao, Weiren

    2015-01-01

    In order to explore the water-holding capacity of dewatered lignite and the contribution of pore structure and oxygen-containing functional groups to it, a kind of typical Chinese lignite was dried under the atmosphere of nitrogen for different temperatures and times, and then was subjected to a process of moisture re-adsorption at the temperature of 25 °C and relative humidity of 75%. Nitrogen adsorption and chemical titration methods were used to examine the pore structure parameters and amounts of oxygen-containing functional groups, respectively. The results indicate that the porous structure and oxygen-containing functional groups in lignite are two main factors influencing the hydrophilicity of dewatered coal, and their contributions are varied with the change of drying conditions. The change of water-holding capacity of pore structure is primarily attributed to the shrinkage or collapse of macro- and mesoporous and it decreases with the increase of drying temperature. The oxygen-containing functional groups mainly include phenolic hydroxyl, carbonyl, carboxyl and methoxyl groups, and the order of their hydrophilicity is: carboxyl group > phenolic hydroxyl group > carbonyl group > methoxyl group. Moreover, the water-holding capacity for the same kind of oxygen-containing functional groups in dewatered coal obtained at different temperature is not a fixed one, their hydrophilic forces decrease with the increase of drying temperature. For the coal samples dried for 60 min under different temperature, the contribution of pore structure and oxygen-containing functional groups to the equilibrium moisture content (EMC) of dewatered lignite is: pore structure > phenolic hydroxyl group > carboxyl group > carbonyl group > methoxyl group. The contribution of total oxygen-containing functional groups to the EMC at below 280 °C is more obvious, and that of pore structure is the principal factor thereafter.

  14. POC-scale testing of an advanced fine coal dewatering equipment/technique. Quarterly progress report, July - September 1996

    SciTech Connect

    Tao, D.; Groppo, J.G.; Parekh, B.K.

    1996-10-01

    The advanced fine-coal cleaning techniques such as column flotation, recovers a low-ash ultra-fine size clean-coal product. However, economical dewatering of the clean coal product to less than 20 percent moisture using conventional technology is difficult. This research program objective is to evaluate a novel coal surface modification technique developed at the University of Kentucky Center for Applied Energy Research in conjunction with conventional and advanced dewatering technique at a pilot scale. The study which is in progress is being conducted at the Powell Mountain Coal Company`s Mayflower preparation plant located in St. Charles, VA. During this quarter laboratory dewatering studies were conducted using a 4-in diameter laboratory chemical centrifuge. The baseline data provided a filter cake with about 32% moisture. Addition of 0.3 kg/t of a cationic surfactant lowered the moisture to 29%. Addition of anionic and non-ionic surfactant was not effective in reducing the filter cake moisture content. In the pilot scale studies, a comparison was conducted between the high pressure and vacuum dewatering techniques. The base line data with high pressure and vacuum filtration provided filter cakes with 23.6% and 27.8% moisture, respectively. Addition of 20 g/t of cationic flocculent provided 21% filter cake moisture using the high pressure filter. A 15% moisture filter cake was obtained using 1.5 kg/t of non-ionic surfactant. Vacuum filter provided about 23% to 25% moisture product with additional reagents. The high pressure filter processed about 3 to 4 times more solids compared to vacuum filter.

  15. Crustal-scale fluid migration and dewatering of the Costa Rica subduction zone

    NASA Astrophysics Data System (ADS)

    Bangs, N. L.; McIntosh, K. D.; Kluesner, J. W.; Silver, E. A.

    2014-12-01

    In 2011 we acquired a large 3D seismic reflection data volume with the R/V Langseth to examine the structure of the Costa Rica margin, NW of the Osa Peninsula. Multibeam bathymetry and backscatter data also acquired during the cruise reveal mud mounds, pockmarks, and gas plumes that indicate numerous, previously unknown, seafloor vent-related features that extend from the lower slope to the outer shelf region (Kluesner et al., 2013). These features imply active or recently active seafloor vents; however, the processes of fluid focusing into vents are not apparent from the seafloor data alone. The 3D seismic reflection data reveal indirect indicators of fluids below the seafloor. In the slope cover sediment, within the uppermost 1000 m of the seafloor, we calculated the RMS amplitude of the seismic reflections to identify vent systems from anomalously high seismic reflection amplitudes. We attribute anomalously high-amplitude zones to fluid-filled fractures and concentrated free gas directly associated with vents. Along the lower slope where a BSR is present, vents inferred from amplitude anomalies are also coincident with local shallow BSR depth anomalies. Fluids feeding these shallow vent systems appear to originate from the underlying fault-cored fold and thrust systems of the margin wedge. High amplitude anomalies within the slope cover lie directly over margin wedge thrust anticlines that develop within the 2-to-8 km thick margin wedge sequence. These anticlines are typically cored by thrusts, many of which themselves have high amplitude, reversed polarity seismic reflections that we interpret as fault zone dilation and active fluid migration. Fluids originating from the plate interface appear to be migrating up toward the seafloor along these thrust faults, as well as along the imbricately stacked stratigraphic horizons within the margin wedge. Fluids become focused into the crest of fold anticlines and directed to the seafloor vent-related features. This crustal scale fluid migration system extends from the lower slope and across much of the shelf implying broad, active dewatering of the seaward most 50 km of the overriding plate. We interpret this large scale fluid migration system as an actively dewatering fold and thrust sequence driven by recent thickening of sediment sequences within the margin wedge.

  16. Membrane-Based Energy Efficient Dewatering of Microalgae in Biofuels Production and Recovery of Value Added Co-Products

    SciTech Connect

    Bhave, Ramesh R; Kuritz, Tanya; Powell, Lawrence E; Adcock, Kenneth Dale

    2012-01-01

    The objective of this paper is to describe the use of membranes for energy efficient biomass harvesting and dewatering. We have evaluated the dewatering of Nannochloropsis sp. with polymeric hollow fiber and tubular inorganic membranes to demonstrate the capabilities of a membrane-based system to achieve microalgal biomass of >150 g/L (dry wt.) and ~99% volume reduction through dewatering. The particle free filtrate containing the growth media is suitable for recycle and reuse. For cost-effective processing, hollow fiber membranes can be utilized to recover 90-95% media for recycle. Tubular membranes can provide additional media and water recovery to achieve target final concentrations. Based on the operating conditions used in this study and taking into scale-up considerations, it can be shown that an integrated hollow fiber-tubular membrane system can process microalgal biomass with at least 80% lower energy requirement compared to traditional processes. Backpulsing was found to be an effective flux maintenance strategy to minimize flux decline at high biomass concentration. An effective chemical cleaning protocol was developed for regeneration of fouled membranes.

  17. Enhanced dewatering of sludge with the composite of bioflocculant MBFGA1 and P(AM-DMC) as a conditioner.

    PubMed

    Guo, Junyuan; Nengzi, Lichao; Zhao, Jing; Zhang, Yuzhe

    2015-04-01

    Bioflocculant MBFGA1 was investigated to be used as a conditioner for sludge dewatering, and the response surface methodology (RSM) was employed to study the enhancing performance of the dewatering process by the composite of MBFGA1 and poly(acrylamide [2-(methacryloyloxy)ethyl]-trimethylammonium chloride) (P(AM-DMC)). Results showed that dry solids (DS) and specific resistance to filtration (SRF) of sludge treated by MBFGA1 alone appeared as 21.7 % and 3.6?×?10(12) m kg(-1), respectively, which were much better than FeCl3, Al2(SO4)3, and polyaluminum chloride (PAC), but poorer than P(AM-DMC) in sludge dewatering. Apart from this, the optimized conditioning process for improving the dewaterability of the sludge conditioned by the composite is MBFGA1 of 1.4 g L(-1), P(AM-DMC) of 0.13 g L(-1), CaCl2 of 56.1 mg L(-1), pH value of 7.5, and agitation speed of 149 rpm. Under this optimal condition, DS and SRF appeared as 29.9 % and 2.2?×?10(12) m kg(-1), respectively. Thus, it is feasible and meaningful to enhance the dewaterability of the sludge by the compound uses of MBFGA1 and P(AM-DMC). PMID:25634018

  18. Estimated Fall Chinook Salmon Survival to Emergence in Dewatered Redds in a Shallow Side Channel of the Columbia River

    SciTech Connect

    McMichael, Geoffrey A.; Rakowski, Cynthia L.; James, B B.; Lukas, Joe

    2005-08-01

    Fall Chinook salmon (Oncorhynchus tshawytscha) often spawn in the tailraces of large hydroelectric dams on the Columbia River. Redds built in shallow habitats downstream of these dams may be periodically dewatered due to hydropower operations prior to the emergence of fry. To determine whether fall Chinook salmon redds were successful in a shallow area subjected to periodic dewatering downstream of Wanapum Dam on the Columbia River, we installed 7 redd caps and monitored fry emergence. Large numbers of live fry were captured from the redds between March 9 and May 18, 2003. Estimated survival from egg to fry for these redds, which were all subjected to some degree of dewatering during the incubation and post-hatch intragravel rearing period, ranged from 16.1 to 63.2 percent and averaged 27.8 percent (assuming 4,500 eggs/redd). The peak emergence date ranged from April 1 to 29, with the average peak about April 14, 2003. Mean fork length of fall Chinook salmon emerging from individual redds ranged from 38.3 to 41.2 mm, and lengths of fish emerging from individual redds increased throughout the emergence period.

  19. Evaluation of hyperbaric filtration for fine coal dewatering. Eleventh quarterly technical progress report, April 1, 1995--June 30, 1995

    SciTech Connect

    Parekh, B.K.; Hogg, R.; Fonseca, A.

    1995-12-01

    The main objectives of the project are to investigate the fundamental aspects of particle-liquid interaction in fine coal dewatering, to conduct laboratory and pilot plant studies on the applicability of hyperbaric filter systems and to develop process conditions for dewatering of fine clean coal to less than 20 percent moisture. The program consist of three phases, namely Phase I - Model Development, Phase II - Laboratory Studies, Phase III - Field Testing. The Pennsylvania State University is leading efforts in Phase I, the University of Kentucky in Phase II, and Consol Inc. in Phase III of the program. All three organizations are involved in all the three phases of the program. The Pennsylvania State University is developing a theoretical model for hyperbaric filtration systems, whereas the University of Kentucky is conducting experimental studies to investigate fundamental aspects of particle-liquid interaction and application of high pressure filter in fine coal dewatering. The optimum filtration conditions identified in Phase I and II will be tested in a Consol Inc. coal preparation plant using an Andritz Ruthner portable hyperbaric filtration unit.

  20. Evaluation of hyperbaric filtration for fine coal dewatering. Twelfth quarterly technical progress report, July 1, 1995--September 30, 1995

    SciTech Connect

    Parekh, B.K.; Hogg, R.; Fonseca, A.

    1996-02-01

    The main objectives of the project are to investigate the fundamental aspects of particle-liquid interaction in fine coal dewatering, to conduct laboratory and pilot plant studies on the applicability of hyperbaric filter systems and to develop process conditions for dewatering of fine clean coal to less than 20 percent moisture. The program consist of three phases, namely: (1) Phase I Model Development; (2) Phase II Laboratory Studies; and (3) Phase III Field Testing. The Pennsylvania State University is leading efforts in Phase I, the University of Kentucky in Phase 11, and Consol Inc. in Phase III of the program. All three organizations are involved in all the three phases of the program. The Pennsylvania State University is developing a theoretical model for hyperbaric filtration systems, whereas the University of Kentucky is conducting experimental studies to investigate fundamental aspects of particle-liquid interaction and application of high pressure filter in fine coal dewatering. The optimum filtration conditions identified in Phase I and II will be tested in a Consol Inc. coal preparation plant using an Andritz Ruthner portable hyperbaric filtration unit.

  1. Evaluation of hyperbaric filtration for fine coal dewatering. Fourth quarterly technical progress report: June 1, 1993--September 30, 1993

    SciTech Connect

    Parekh, B.K.; Hogg, R.; Fonseca, A.

    1993-12-31

    The main objectives of the project are to investigate the fundamental aspects of particle-liquid interaction in fine coal dewatering, to conduct laboratory and pilot plant studies on the applicability of hyperbaric filter systems and to develop process conditions for dewatering of fine clean coal to less than 20 percent moisture. The program consist of three phases, Model Development, Laboratory Studies, and Field Testing. The Pennsylvania State University is leading efforts in Phase 1, the University of Kentucky in Phase 2, and Consol Inc. in Phase 3 of the program. All three organizations are involved in all the three phases of the program. The Pennsylvania State University is developing a theoretical model for hyperbaric filtration systems, whereas the University of Kentucky is conducting experimental studies to investigate fundamental aspects of particle-liquid interaction and application of high pressure filter in fine coal dewatering. The optimum filtration conditions identified in phase 1 and 2 will be tested in a Consol Inc. coal preparation plant using an Andritz Ruthner portable hyperbaric filtration unit.

  2. Engineering development of advanced physical fine coal cleaning for premium fuel applications: Subtask 3.3 - dewatering studies

    SciTech Connect

    Yoon, R. H.; Phillips, D. I.; Sohn, S. M.; Luttrell, G. H.

    1996-10-01

    If successful, the novel Hydrophobic Dewatering (HD) process being developed in this project will be capable of efficiently removing moisture from fine coal without the expense and other related drawbacks associated with mechanical dewatering or thermal drying. In the HD process, a hydrophobic substance is added to a coal-water slurry to displace water from the surface of coal, while the spent hydrophobic substance is recovered for recycling. For this process to have commercialization potential, the amount of butane lost during the process must be small. Earlier testing revealed the ability of the hydrophobic dewatering process to reduce the moisture content of fine coal to a very low amount as well as the determination of potential butane losses by the adsorption of butane onto the coal surface. Work performed in this quarter showed that the state of oxidation affects the amount of butane adsorbed onto the surface of the coal and also affects the final moisture content. the remaining work will involve a preliminary flowsheet of a continuous bench-scale unit and a review of the economics of the system. 1 tab.

  3. An integrated approach to optimize the conditioning chemicals for enhanced sludge conditioning in a pilot-scale sludge dewatering process.

    PubMed

    Zhai, Lin-Feng; Sun, Min; Song, Wei; Wang, Gan

    2012-10-01

    An integrated approach incorporating response surface methodology (RSM), grey relational analysis, and fuzzy logic analysis was developed to quantitatively evaluate the conditioning chemicals in sludge dewatering process. The polyacrylamide (PAM), ferric chloride (FeCl(3)) and calcium-based mineral powders were combined to be used as the sludge conditioners in a pilot-scale sludge dewatering process. The performance of conditioners at varied dosages was comprehensively evaluated by taking into consideration the sludge dewatering efficiency and chemical cost of conditioner. In the evaluation procedure, RSM was employed to design the experiment and to optimize the dosage of each conditioner. The grey-fuzzy logic was established to quantify the conditioning performance on the basis of grey relational coefficient generation, membership function construction, and fuzzy rule description. Based on the evaluation results, the optimal chemical composition for conditioning was determined as PAM at 4.62 g/kg DS, FeCl(3) at 55.4 g/kg DS, and mineral powders at 30.0 g/kg DS. PMID:22858481

  4. Dewatered sewage biosolids provide a productive larval habitat for stable flies and house flies (Diptera: Muscidae).

    PubMed

    Doud, C W; Taylor, D B; Zurek, L

    2012-03-01

    Species diversity and seasonal abundance of muscoid flies (Diptera: Muscidae) developing in biosolid cake (dewatered biosolids) stored at a wastewater treatment facility in northeastern Kansas were evaluated. Emergence traps were deployed 19 May through 20 October 2009 (22 wk) and 27 May through 18 November 2010 (25 wk). In total, 11,349 muscoid flies were collected emerging from the biosolid cake. Stable flies (Stomoxys calcitrans (L.)) and house flies (Musca domestica (L.)), represented 80 and 18% of the muscoid flies, respectively. An estimated 550 stable flies and 220 house flies per square-meter of surface area developed in the biosolid cake annually producing 450,000 stable flies and 175,000 house flies. Stable fly emergence was seasonally bimodal with a primary peak in mid-July and a secondary peak in late August. House fly emergence peaked with the first stable fly emergence peak and then declined gradually for the remainder of the year. House flies tended to emerge from the biosolid cake sooner after its deposition than did stable flies. In addition, house fly emergence was concentrated around midsummer whereas stable fly emergence began earlier in the spring and continued later into the fall. Biosolid age and temperature were the most important parameters affecting emergence for house flies and stable flies, whereas precipitation was not important for either species. This study highlights the importance of biosolid cake as a larval developmental habitat for stable flies and house flies. PMID:22493845

  5. Strategies for Treating and Dewatering Contaminated Soils and Sediments Simultaneously - 13389

    SciTech Connect

    Bickford, Jody; Foote, Martin

    2013-07-01

    MSE Technology Applications, Inc. (MSE) was asked to perform a series of treatability studies by Global Technologies, Inc. (Global) and M{sup 2} Polymer Technologies, Inc. (M{sup 2} Polymer) using Global's metal treatment agent, Molecular Bonding System (MBS) and M{sup 2} Polymer's super-absorbent polymer, Waste Lock 770 (WL-770). The primary objective of the study was to determine if the two products could be used as a one-step treatment process to reduce the leachability of metals and de-water soils and/or sediments simultaneously. Three phases of work were performed during the treatability study. The first phase consisted of generating four bench-scale samples: two treated using only MBS and two treated using only WL- 770, each at variable concentrations. The second phase consisted of generating nine bench-scale samples that were treated using MBS and WL-770 in combination with three different addition techniques. The third phase consisted of generating four intermediate-scale samples that were treated using MBS and WL-770 simultaneously. The soils used in the treatability study were collected at the Mike Mansfield Advanced Technology Center in Butte, Montana. The collected soils were screened at 4 mesh (4.75 millimeters (mm)) to remove the coarse fraction of the soil and spiked with metallic contaminants of lead, cadmium, nickel, mercury, uranium, chromium, and zinc. (authors)

  6. Compressional rheology: A tool for understanding compressibility effects in sludge dewatering.

    PubMed

    Stickland, Anthony D

    2015-10-01

    Water and wastewater treatment sludges exhibit compressible behaviour due to flocculation and aggregation. At a critical solids concentration called the gel point, which is as low as 1-2 v/v%, a continuous interconnected network of particles is formed that can resist an applied load. The applied load (mechanical filtration pressure or buoyancy in settling for example) must exceed the network strength in order to consolidate the network. The network strength increases with solids concentration such that the equilibrium extent of consolidation is a function of the applied load. Improved understanding of the nature of compressible suspensions can have a significant impact through optimising design and operation of sludge handling and dewatering processes. This work gives an overview of compressional rheology, which has proven to be a useful tool for describing the solid-liquid separation of compressible systems. This is followed by three examples where compressibility effects must be taken into account, namely the extraction of material properties for extremely compressible materials, consolidation and crust formation during constant rate evaporation, and the effect of bed height in thickening. PMID:26304591

  7. Particulates in hydrometallurgy: Part II. Dewatering behavior of unflocculated laterite acid leach residues

    NASA Astrophysics Data System (ADS)

    Briceno, A.; Osseo-Asare, K.

    1995-02-01

    The effects of ore type and leaching conditions ( e.g., temperature and solid/liquid ratio) on the settling behavior of laterite acid leach residues were investigated. Settling rate, supernatant turbidity, and filtrability of the slurry were used in evaluating the settling behavior. The slurries showed three different regimes of sedimentation, involving free, hindered, and compression settling behavior. An improvement in the dewatering characteristics of the leach residues was observed as the leaching temperature was increased. Furthermore, the leach residues showed markedly different settling behaviors depending on the temperature. Below 175°C, the settling rate for both 2.5 and 25 pct solids increased steadily with temperature. However, the results indicated clearly that at higher temperatures (>175°C), there is a steep increase in settling rate. These pronounced differences in settling behavior with temperature increase are believed to be due to the sharp increase in particle size above 175°C. The mineral content in the ore has a great effect on the settling behavior of the leach residues. It was found that the oxide-silicate material (Ore No. 2 leach residues) showed a lower settling rate than the iron-rich material (Ore No. 1 leach residues). This behavior is attributable to the presence of a gelatinous, siliceous product in the Ore No. 2 leached pulp.

  8. Effects of dilution ratio and Fe° dosing on biohydrogen production from dewatered sludge by hydrothermal pretreatment.

    PubMed

    Yu, Li; Jiang, Wentian; Yu, Yang; Sun, Chenglin

    2014-01-01

    Biohydrogen fermentation of dewatered sludge (DS) with sewage at ratios from 4:1 to 1:20 was investigated. Hydrothermal pretreatment of the sludge solution was performed to accelerate the organic release from the solid phase. The maximum hydrogen yield of 26.3 ± 0.5 mL H?/g volatile solid (VS) was obtained at a 1:10 ratio. Although addition of zero valent iron (ZVI) to anaerobic system was not new, the study of dosing it to enhance the biohydrogen yield might be the first attempt. While Fe° plate slightly affected the hydrogen yield, Fe° powder improved the amount of hydrogen by 16% and shortened the lag time by 36%. The state of bacteria in the reactor added with ZVI powder was changed and the key enzyme activity was improved as well. Correspondingly, the mechanism of ZVI in accelerating the biofermentation process was also proposed. Our research provides a solution for the centralized treatment of DS in a city. PMID:25244137

  9. Dewatering of Chlorella pyrenoidosa using diatomite dynamic membrane: filtration performance, membrane fouling and cake behavior.

    PubMed

    Zhang, Yalei; Zhao, Yangying; Chu, Huaqiang; Zhou, Xuefei; Dong, Bingzhi

    2014-01-01

    The diatomite dynamic membrane (DDM) was utilized to dewater Chlorella pyrenoidosa of 2 g dry weight/L under continuous-flow mode, whose ultimate algae concentration ranged from 43 g to 22 g dry weight/L of different culture time. The stable flux of DDM could reach 30 L/m(2) h over a 24 h operation time without backwash. Influences of extracellular organic matters (EOM) on filtration behavior and membrane fouling were studied. The DDM was divided into three sub-layers, the slime layer, the algae layer and the diatomite layer from the outside to the inside of the cake layer based on components and morphologies. It was found that EOM caused membrane fouling by accumulating in the slime and algae layers. The DDM intercepted polysaccharides, protein-like substances, humic-like substances and some low-MW organics. Proteins were indicated the major membrane foulants with increased protein/polysaccharide ratio from the slime layer to the diatomite layer as culture time increased. This method could be applied to subsequent treatment of microalgae coupling technology of wastewater treatment or microalgae harvesting for producing biofuel. PMID:24148755

  10. Mining nutrients (N, K, P) from urban source-separated urine by forward osmosis dewatering.

    PubMed

    Zhang, Jiefeng; She, Qianhong; Chang, Victor W C; Tang, Chuyang Y; Webster, Richard D

    2014-03-18

    Separating urine from domestic wastewater promotes a more sustainable municipal wastewater treatment system. This study investigated the feasibility of applying a forward osmosis (FO) dewatering process for nutrient recovery from source-separated urine under different conditions, using seawater or desalination brine as a low-cost draw solution. The filtration process with the active layer facing feed solution exhibited relatively high water fluxes up to 20 L/m(2)-h. The process also revealed relatively low rejection to neutral organic nitrogen (urea-N) in fresh urine but improved rejection of ammonium (50-80%) in hydrolyzed urine and high rejection (>90%) of phosphate, potassium in most cases. Compared to simulation based on the solution-diffusion mechanism, higher water flux and solute flux were obtained using fresh or hydrolyzed urine as the feed, which was attributed to the intensive forward nutrient permeation (i.e., of urea, ammonium, and potassium). Membrane fouling could be avoided by prior removal of the spontaneously precipitated crystals in urine. Compared to other urine treatment options, the current process was cost-effective and environmentally friendly for nutrient recovery from urban wastewater at source, yet a comprehensive life-cycle impact assessment might be needed to evaluate and optimize the overall system performance at pilot and full scale operation. PMID:24564179

  11. Effects of solids concentration on activated sludge deflocculation, conditioning and dewatering.

    PubMed

    Mikkelsen, L H; Keiding, K

    2001-01-01

    Optimum conditioning of activated sludge in terms of minimum CST was shown to correspond to the complete removal of turbidity, and the increase in turbidity with shear due to e.g. pumping is therefore expected to affect conditioning. The optimum polymer dosage was directly related to the turbidity of activated sludge after two minutes shear, and was considerably lower than the dosage required for charge neutralisation. The turbidity produced by shear increased more than is proportional with solids concentration and was directly related to the apparent viscosity. It is suggested that increasing solids concentration causes increased surface erosion when network structures are broken, and this causes increases in turbidity and required polymer dosage per solids mass. For Aby activated sludge, optimum polymer dosage per solids mass increased by 52% when the solids concentration was increased from 8.2 to 13.7 g SS/l. Modelling of the effect of solids concentration predicts even higher increases in required polymer dosage for higher solids concentrations. This means that reduced thickening prior to pumping and conditioning may be desirable when the hydraulic capacity of the dewatering device is sufficient. Similar trends were observed for an anaerobically digested sludge. For this sludge, reduction of turbidity with FeCl3 reduced the polymer demand. PMID:11548014

  12. Ground-water conditions and effects of mine dewatering in Desert Valley, Humboldt and Pershing Counties, northwestern Nevada, 1962-91

    USGS Publications Warehouse

    Berger, D.L.

    1995-01-01

    Desert Valley is a 1,200-square-mile, north- trending, structural basin, about 30 miles northwest of Winnemucca, Nevada. Unconsolidated basin-fill deposits exceeding 7,000 feet in thickness constitute the primary ground-water reservoir. Dewatering operations at an open-pit mine began in the Spring of 1985 in the northeast part of Desert Valley. Ground-water withdrawal for mine dewatering in 1991 was greater than three times the estimated average annual recharge from precipitation. The mine discharge water has been allowed to flow to areas west of the mine where it has created an artificial wetlands. This report documents the 1991 hydrologic conditions in Desert Valley and the change in conditions since predevelopment (pre-1962). It also summarizes the results of analyzing the simulated effects of open-pit mine dewatering on a basin-wide scale over time. Water-level declines associated with the dewatering have propagated north and south of the mine, but have been attenuated to the west due to the infiltration beneath the artificial wetlands. Maximum water-level declines beneath the open pits at the mine, as of Spring 1991, are about 300 feet. Changes in the hydrologic conditions since predevelopment are observed predominantly near the dewatering operations and the associated discharge lakes. General ground-water chemistry is essentially unchanged since pre- development. On the basis of a ground-water flow model used to simulate mine dewatering, a new equilibrium may slowly be approached only after 100 years of recovery from the time mine dewatering ceases.

  13. Model development and evaluation of methane potential from anaerobic co-digestion of municipal wastewater sludge and un-dewatered grease trap waste.

    PubMed

    Yalcinkaya, Sedat; Malina, Joseph F

    2015-06-01

    The performance of anaerobic co-digestion of municipal wastewater sludge with un-dewatered grease trap waste was assessed using modified biochemical methane potential tests under mesophilic conditions (35°C). Methane potentials, process inhibition and chemical behavior of the process were analyzed at different grease trap waste feed ratios on volatile solids basis. Nonlinear regression analyses of first order reaction and modified Gompertz equations were performed to assist in interpretation of the experimental results. Methane potential of un-dewatered grease trap waste was measured as 606 mL CH4/g VS(added), while methane potential of municipal wastewater sludge was only 223 mL CH4/g VS(added). The results indicated that anaerobic digestion of grease trap waste without dewatering yields less methane potential than concentrated/dewatered grease trap waste because of high wastewater content of un-dewatered grease trap waste. However, anaerobic co-digestion of municipal wastewater sludge and grease trap waste still yields over two times more methane potential and approximately 10% more volatile solids reduction than digestion of municipal wastewater sludge alone. The anaerobic co-digestion process inhibitions were reported at 70% and greater concentrated/dewatered grease trap waste additions on volatile solids basis in previous studies; however, no inhibition was observed at 100% un-dewatered grease trap waste digestion in the present study. These results indicate that anaerobic co-digestion of un-dewatered grease trap waste may reduce the inhibition risk compared to anaerobic co-digestion of concentrated/dewatered grease trap waste. In addition, a mathematical model was developed in this study for the first time to describe the relationship between grease trap waste feed ratio on volatile solids basis and resulting methane potential. Experimental data from the current study as well as previous biochemical methane potential studies were successfully fit to this relationship and allowed estimation of key performance parameters that provide additional insight into the factors affecting biochemical methane potential. PMID:25818384

  14. POC-scale testing of an advanced fine coal dewatering equipment/technique. Quarterly technical progress report 3, April--June 1995

    SciTech Connect

    Groppo, J.G.; Parekh, B.K.

    1995-08-05

    Economical dewatering of an ultra-fine clean coal product to a 20% or lower level moisture will be an important step in successful implementation of the advanced fine coal cleaning processes. The main objective of the proposed program is to evaluate a novel surface modification technique, which utilizes the synergistic effect of metal ions-surfactant combination, for dewatering of ultra-fine clean coal on a proof-of-concept (POC) scale of 1 to 2 tph. The novel surface modification technique developed at the UKCAER will be evaluated using vacuum, centrifuge, and hyperbaric filtration equipment. Dewatering tests will be conducted using the fine clean coal froth produced by the column flotation units at the Powell Mountain Coal Company, Mayflower Preparation Plant in St. Charles, Virginia. The POC-scale studies will be conducted on two different types of clean coal, namely, high sulfur and low sulfur clean coal. The Mayflower Plant processes coals from five different seams, thus the dewatering studies results could be generalized for most of the bituminous coals. During this quarter, addition of reagents such as ferric ions and a novel concept of in-situ polymerization (ISP) was studied in the laboratory. Using the ISP approach with vacuum filtration provided 25% moisture filter cake compared to 65.5% moisture obtained conventionally without using the ISP. A series of dewatering tests were conducted using the Andritz hyperbaric pilot filter unit with high sulfur clean coal slurry.

  15. Remedial Action Plan and site design for stabilization of the inactive uranium mill tailings site at Durango, Colorado: Attachment 5, Dewatering report. Revised final report

    SciTech Connect

    Not Available

    1991-12-01

    This report provides an update on dewatering activities at the Durango disposal embankment and presents recommendations for the work required to complete the closure of the cell in 1990 (Section 2). In October 1989, test pit investigations were performed and a toe trench was excavated at the eastern slope of the disposal embankment. A description and results of the test pit investigations along with the implications . of the results relative to the over . all dewatering effort are discussed in Sections 3 through 5. Installation and performance of the 17-well dewatering system were previously described in` the ``StatusReport on Dewatering of Disposal Embankment`` issued in September, 1989. Additional studies are still on-going and are described in Section 6. Laboratory analysis continues on samples taken from the test pits. TAC`s characterization of the hydrogeological conditions at the Durango site is also proceeding. Results of these studies will be presented in subsequent reports. Appendices A and B present construction details of the well point system, toe trench and holding pond. Appendix C summarizes the performance-of the 17 pumping wells prior to winter shutdown and provides information on pumping rates, drawdowns, and disposition of the wells. Appendix D outlines the chronology of the dewatering effort to date.

  16. A new model of coal-water interaction and relevance for dewatering. Final report

    SciTech Connect

    Suuberg, E.M.; Yun, Y.; Lilly, W.D.; Leung, K.; Gates, T.; Otake, Y.; Deevi, S.C.

    1995-02-01

    This project was concerned with developing an improved understanding of how moisture is held in coals. There is a concern that the historically held view, that capillary condensation in pores plays a significant role, could not be correct, since the coal shrinks and swells in response to moisture loss and gain. Thus there is no well-defined pore system for holding the moisture. This appears true for a range of ranks from lignite to high volatile bituminous coal. Instead, it appears that something more like classical swelling of coals in solvents is responsible. This study examined this hypothesis by various means, considering both the mixing thermodynamics of coal and water (or coal and other swelling solvents) and by examining coal`s elastic response. The conclusion is that water does indeed behave like many other swelling solvents, but is a somewhat poor swelling solvent. The structure of the water swollen coal appears to remain fairly glassy, implying that many non-covalent crosslinks remain unbroken. The water interacts with coal only at certain types of adsorption sites. This is consistent with a second historical view that polar functionality is responsible for water retention. The filling of these sites, somewhat surprisingly, appeared to involve a strong enthalpic driving force, rather than the entropic driving force that characterizes solvent swelling in other solvents. The practical importance of these results for thermal dewatering processes is that the historical view is supported. That is, that pyrolytic polar group removal is necessary. An alternative suggestion, based upon attempts to further crosslink coal, has not received support.

  17. Study of de-watering from the gelatinous precipitate formed during co-precipitation of Nd-YAG powder

    NASA Astrophysics Data System (ADS)

    Karmakar, Sanjib; Sharma, Rachna; Pathak, S. K.; Gupta, S. M.; Gupta, P. K.

    2013-02-01

    Neodymium doped Yttrium Aluminium Garnet (Nd:YAG) ceramics have been synthesised using coprecipitation technique and high temperature vacuum sintering. Gelatinous like precipitates were obtained when precursors of Nd, Al and Yb-nitrate solutions are co-precipitated using ammonia co-precipitant. De-watering from the gelatinous like precipitates is a big challenge and it possesses difficulty in filtration. Evaporation of water by heating resulted in strong agglomerated powder. Different agents were used to ease the filtration process, which is correlated with the phase in the calcined powder.

  18. Study of de-watering from the gelatinous precipitate formed during co-precipitation of Nd-YAG powder

    SciTech Connect

    Karmakar, Sanjib; Sharma, Rachna; Pathak, S. K.; Gupta, S. M.; Gupta, P. K.

    2013-02-05

    Neodymium doped Yttrium Aluminium Garnet (Nd:YAG) ceramics have been synthesised using coprecipitation technique and high temperature vacuum sintering. Gelatinous like precipitates were obtained when precursors of Nd, Al and Yb-nitrate solutions are co-precipitated using ammonia co-precipitant. De-watering from the gelatinous like precipitates is a big challenge and it possesses difficulty in filtration. Evaporation of water by heating resulted in strong agglomerated powder. Different agents were used to ease the filtration process, which is correlated with the phase in the calcined powder.

  19. POC-scale testing of an advanced fine coal dewatering equipment/technique. Quarterly technical progress report, April 1996--June 1996

    SciTech Connect

    Tao, D.; Groppo, J.G.; Parekh, B.K.

    1996-07-31

    Froth flotation technique is an effective and efficient process for recovering of ultra-fine (minus 74 {mu}m) clean coal. Economical dewatering of an ultra-fine clean coal product to a 20 percent level moisture will be an important step in successful implementation of the advanced cleaning processes. This project is a step in the Department of Energy`s program to show that ultra-clean coal could be effectively dewatered to 20 percent or lower moisture using either conventional or advanced dewatering techniques. The cost sharing contract effort is for 36 months beginning September 30, 1994. This report discusses technical progress made during the quarter from April 1 - June 30, 1996.

  20. POC-scale testing of an advanced fine coal dewatering equipment/technique. Quarterly technical progress report, No. 4, July 1995--September 1995

    SciTech Connect

    Groppo, J.G.; Parekh, B.K.

    1995-11-06

    Froth flotation technique is an effective and efficient process for recovering of ultra-fine (minus 74 {mu}m) clean coal. Economical dewatering of an ultra-fine clean coal product to a 20 percent level moisture will be an important step in successful implementation of the advanced cleaning processes. This project is a step in the Department of Energy`s program to show that ultra-clean coal could be effectively dewatered to 20 percent or lower moisture using either conventional or advanced dewatering techniques. The cost-sharing contract effort is for 36 months beginning September 30, 1994. This report discusses technical progress made during the quarter from July 1 - September 29, 1995.

  1. POC-scale testing of an advanced fine coal dewatering equipment/technique. Quarterly technical progress report 2, January 1995--March 1995

    SciTech Connect

    Groppo, J.G.; Parekh, B.K.

    1995-05-05

    Froth flotation technique is an effective and efficient process for recovering of ultra-fine (minus 74 {mu}m) clean coal. Economical dewatering of an ultra-fine clean coal product to a 20 percent level moisture will be an important step in successful implementation of the advanced cleaning processes. This project is a step in the Department of Energy`s program to show that ultra-clean coal could be effectively dewatered to 20 percent or lower moisture using either conventional or advanced dewatering techniques. The cost-sharing contract effort is for 36 months beginning September 30, 1994. This report discusses technical progress made during the quarter from January 1 to March 31, 1995.

  2. Development of the electroacoustic dewatering (EAD) process for fine/ultrafine coal: Second quarterly progress report period ending 31 March 1989

    SciTech Connect

    Not Available

    1989-04-18

    Battelle, in cooperation with the Electric Power Research Institute (EPRI), Ashbrook-Simon-Hartley (ASH), Kaiser Engineers (KE), Lewis Corporation, and Prof. S.H. Chiang of the University of Pittsburgh, is developing an advanced process for the dewatering of fine and ultrafine coals. The advanced process, called Electroacoustic Dewatering (EAD), capitalizes on the adaptation of synergistic effects of electric and acoustic fields to a commercial belt filter press design that is used in many other applications. The EAD equipment is described. 2 figs.

  3. Decolorization and biodegradation of the Congo red by Acinetobacter baumannii YNWH 226 and its polymer production's flocculation and dewatering potential.

    PubMed

    Li, Ruijing; Ning, Xun-an; Sun, Jian; Wang, Yujie; Liang, Jieying; Lin, Meiqing; Zhang, Yaping

    2015-10-01

    The strain Acinetobacter baumannii YNWH 226 was utilized to degrade Congo red (CR) under aerobic conditions. CR was employed as the sole carbon source to produce extracellular polymeric substances (EPS) used as potent bioflocculants in this strain. A total of 98.62% CR was removed during the 48-h decoloration experiments using CR (100 mg/L). A total of 83% bioadsorption and 65% biodegradation were responsible for the decoloration and degradation of CR through the strain. The bioflocculant showed high flocculation activity and dewaterability on textile dyeing sludge. A maximum flocculation of 78.62% with a minimum SBF of 3.07×10(9) s(2)/g and a CST of 58.4 s were achieved. We investigated the internal relationship between the decolorization efficiency of YNWH 226 and the flocculation activity and dewatering capacity of its EPS. The components and structure of the EPS highly influenced the decolorization efficiency of CR and the flocculation activity and dewatering capacity on sludge. PMID:26207869

  4. Survival and behaviour of juvenile unionid mussels exposed to thermal stress and dewatering in the presence of a sediment temperature gradient

    USGS Publications Warehouse

    Archambault, L.; Cope, W. Gregory; Kwak, Thomas J.

    2014-01-01

    Our findings suggest that rising stream water temperature and dewatering may directly impact freshwater mussel abundance by causing mortality and may have indirect impacts via sublethal effects. Reduced burrowing capacity may hamper ability to escape predation or unfavourably high or low flows, and decreased byssus production may inhibit attachment and dispersal capabilities in juveniles.

  5. POC-scale testing of an advanced fine coal dewatering equipment/technique: Quarterly technical progress report No. 9, October 1996--December 1996

    SciTech Connect

    Tao, D.; Groppo, J.G.; Parekh, B.K.

    1997-01-21

    The advanced fine-coal cleaning techniques such as column flotation, recovers a low-ash ultra-fine size clean-coal product. However, economical dewatering of the clean coal product to less than 20 percent moisture using conventional technology is difficult. This research program objective is to evaluate a novel coal surface modification technique developed at the University of Kentucky Center for Applied Energy Research in conjunction with conventional and advanced dewatering technique at a pilot scale at the Powell Mountain Coal Company`s Mayflower preparation plant located in St. Charles, VA. During this quarter in the laboratory dewatering studies were conducted using copper and aluminum ions showed that for the low sulfur clean coal slurry addition of 0.1 Kg/t of copper ions was effective in lowering the filter cake moisture from 29 percent to 26.3 percent. Addition of 0.3 Kg/t of aluminum ions provided filter cake with 28 percent moisture. For the high sulfur clean coal slurry 0.5 Kg/t of copper and 0.1 Kg/t of aluminum ions reduced cake moisture from 30.5 percent to 28 percent respectively. Combined addition of anionic (10 g/t) and cationic (10 g/t) flocculants was effective in providing a filter cake with 29.8 percent moisture. Addition of flocculants was not effective in centrifuge dewatering. In pilot scale screen bowl centrifuge dewatering studies it was found that the clean coal slurry feed rate of 30 gpm was optimum to the centrifuge, which provided 65 percent solids capture. Addition of anionic or cationic flocculants was not effective in lowering of filter cake moisture, which remained close to 30 percent for both clean coal slurries.

  6. Reassessment of the effects of construction dewatering on ground-water levels in the Cowles Unit, Indiana Dunes National Lakeshore, Indiana : Supplement to Geological Survey Water Resources Investigations 78-138

    USGS Publications Warehouse

    Gillies, Daniel C.; Lapham, Wayne W.

    1980-01-01

    A revised dewatering plan for the construction of a nuclear power plant at the Northern Indiana Public Service Company 's (NIPSCO) Bailly Generating Station and evidence that suggests that a change in the characteristics of the confining unit 2 in and near Cowles Bog National Landmark may exist have resulted in a reassessment of the effects of construction dewatering on ground-water levels in the Indiana Dunes National Lakeshore. Model results indicate that the revision in the dewatering plan produces water-level declines that do not differ significantly from those described previously. However, when the change in the confining unit beneath Cowles Bog is considered, simulations of the simultaneous decline of a seepage mound after sealing of the fly-ash-ponds and the second phase of construction dewatering indicate that the simulated water-level declines in the aquifer unit 1 at Cowles Bog may be below the water levels tolerated by the National Park Service after 18 months. The water levels may even decline below the tolerable levels in spite of NIPSCO 's proposed plan of artificially recharging the aquifer unit 1 near the excavation site at 400 gal/min. The magnitude of the simulated water-level declines in unit 1 within the Lakeshore, caused by pumping from the excavation, depends on the relation in time between the second phase of dewatering and the decline of the seepage mound after sealing of the fly-ash-ponds, but not on the duration of dewatering beyond 18 months. (USGS)

  7. Predicting spread of invasive exotic plants into de-watered reservoirs following dam removal on the Elwha River, Olympic National Park, Washington

    USGS Publications Warehouse

    Woodward, Andrea; Torgersen, Christian E.; Chenoweth, Joshua; Beirne, Katherine; Acker, Steve

    2011-01-01

    The National Park Service is planning to start the restoration of the Elwha River ecosystem in Olympic National Park by removing two high head dams beginning in 2011. The potential for dispersal of exotic plants into dewatered reservoirs following dam removal, which would inhibit restoration of native vegetation, is of great concern. We focused on predicting long-distance dispersal of invasive exotic plants rather than diffusive spread because local sources of invasive species have been surveyed. We included the long-distance dispersal vectors: wind, water, birds, beavers, ungulates, and users of roads and trails. Using information about the current distribution of invasive species from two surveys, various geographic information system techniques and models, and statistical methods, we identified high-priority areas for Park staff to treat prior to dam removal, and areas of the dewatered reservoirs at risk after dam removal.

  8. Comparison of digestate from solid anaerobic digesters and dewatered effluent from liquid anaerobic digesters as inocula for solid state anaerobic digestion of yard trimmings.

    PubMed

    Xu, Fuqing; Wang, Feng; Lin, Long; Li, Yebo

    2016-01-01

    To select a proper inoculum for the solid state anaerobic digestion (SS-AD) of yard trimmings, digestate from solid anaerobic digesters and dewatered effluent from liquid anaerobic digesters were compared at substrate-to-inoculum (S/I) ratios from 0.2 to 2 (dry basis), and total solids (TS) contents from 20% to 35%. The highest methane yield of around 244L/kg VSfeed was obtained at an S/I ratio of 0.2 and TS content of 20% for both types of inoculum. The highest volumetric methane productivity was obtained with dewatered effluent at an S/I ratio of 0.6 and TS content of 24%. The two types of inoculum were found comparable regarding methane yields and volumetric methane productivities at each S/I ratio, while using dewatered effluent as inoculum reduced the startup time. An S/I ratio of 1 was determined to be a critical level and should be set as the upper limit for mesophilic SS-AD of yard trimmings. PMID:26575617

  9. POC-scale testing of an advanced fine coal dewatering equipment/technique. Quarterly technical progress report No. 5, October--December, 1995

    SciTech Connect

    Groppo, J.G.; Parekh, B.K.

    1996-02-01

    Froth flotation technique is an effective and efficient process for recovering of ultra-fine (minus 74{mu}m) clean coal. Economical dewatering of an ultrafine clean coal product to a 20% level moisture will be an important step in successful implementation of the advanced cleaning processes. The main objective of the proposed program is to evaluate a novel surface modification technique, which utilizes the synergistic effect of metal ions-surfactant combination, for dewatering of ultra-fine clean coal on a proof-of-concept scale of 1 to 2 tph. The novel surface modification technique developed at the the University of Kentucky Center for Applied Energy Research will be evaluated using vacuum, centrifuge, and hyperbaric filtration equipment. Dewatering tests will be conducted using the fine clean coal froth produced by the column flotation units at the Powell Mountain Coal Company, Mayflower Preparation Plant in St. Charles, Virginia. The POC-scale studies will be conducted on two different types of clean coal, namely, high sulfur and low sulfur clean coal. Accomplishments for the past quarter are described.

  10. Engineering support services for the DOE/GRI coal gasification research program. Evaluation of one method of peat harvesting and dewatering

    SciTech Connect

    Bostwick, L.E.; Fruchtbaum, J.; Hubbard, D.A.

    1981-03-01

    This study assumes that the harvesting and dewatering facilities are self-sufficient in generation of the steam and electric power requirements of the operations, fueled by peat product at 50 percent moisture. Dredges and their associated pumps use diesel fuel. Consequently, about 52 percent of the peat removed from the bog is either used for fuel or lost in dewatering. The study is confined to wet harvesting of peat by dredging and transport of the peat as a low-solids slurry over significant distances, which in turn leads to major capital costs for transport equipment and, at least for slurry handling, high operating costs for transportation fuel. Only commercially available equipment was considered in the design of the harvesting and dewatering operations; as a consequence, the equipment is poorly matched for the scale of this operation. Economics developed for the peat gasification plant producing 250 billion Btu per day of SNG indicate that for an average gas cost of $5.00 per million Btu the cost of the peat feed at 50 percent moisture must not exceed $1.57 per million Btu. If the total plant investment for the gasification plant ranges +-30 percent, the peat feed cost must be in the range of $1.18 to 1.91 per million Btu. This contrasts most unfavorably with the estimated peat costs of $3.76 to $4.58 per million Btu developed in the present study.

  11. Start-up of a full-scale deammonification SBR-treating effluent from digested sludge dewatering.

    PubMed

    Lackner, Susanne; Thoma, Konrad; Gilbert, Eva M; Gander, Wolfgang; Schreff, Dieter; Horn, Harald

    2015-01-01

    This study shows the start-up and operation of a full-scale sequencing batch reactor (SBR) with a volume of 550 m³ for deammonification of reject water from sludge dewatering over the first 650 days of operation. The SBR was operated with discontinuous aeration and achieved an optimum of around 85% of ammonium removal at a load of 0.17 kg m?³ d?¹. The application of batch tests for the activity measurement of aerobic ammonium and nitrite oxidizing bacteria and anaerobic ammonium oxidizing bacteria were proven to support the identification of setbacks in reactor operation. Furthermore, the calculation of the oxygen uptake rates from online oxygen measurements helped to explain the overall reactor performance. The aeration regime is a key parameter for stable operation of such an SBR for deammonification. At aeration/non-aeration time ranges from 6-9 min, the best results with respect to turnover rates and low nitrate production were achieved. Compared with the nitrification/denitrification SBR operated in parallel with methanol as the carbon source, a significant reduction in costs for energy and chemicals was achieved. The costs for maintenance slightly increased. PMID:25746647

  12. Nitrogen dynamics model for a pilot field-scale novel dewatered alum sludge cake-based constructed wetland system.

    PubMed

    Kumar, J L G; Zhao, Y Q; Hu, Y S; Babatunde, A O; Zhao, X H

    2015-01-01

    A model simulating the effluent nitrogen (N) concentration of treated animal farm wastewater in a pilot on-site constructed wetland (CW) system, using dewatered alum sludge cake (DASC) as wetland substrate, is presented. The N-model was developed based on the Structural Thinking Experiential Learning Laboratory with Animation software and is considering organic nitrogen, ammonia nitrogen (NH3) and nitrate nitrogen (NO3-N) as the major forms of nitrogen involved in the transformation chains. Ammonification (AMM), ammonia volatilization, nitrification (NIT), denitrification, plant uptake, plant decaying and uptake of inorganic nitrogen by algae and bacteria were considered in this model. pH, dissolved oxygen, temperature, precipitation, solar radiation and nitrogen concentrations were considered as forcing functions in the model. The model was calibrated by observed data with a reasonable agreement prior to its applications. The simulated effluent detritus nitrogen, NH4-N, NO3-N and TN had a considerably good agreement with the observed results. The mass balance analysis shows that NIT accounts for 65.60%, adsorption (ad) (11.90%), AMM (8.90%) followed by NH4-N (Plants) (5.90%) and NO3-N (Plants) (4.40%). The TN removal was found 52% of the total influent TN in the CW. This study suggested an improved overall performance of a DASC-based CW and efficient N removal from wastewater. PMID:25179044

  13. InSAR analysis of aquifer-system response to 20 years of mine-dewatering in the Carlin gold trend, north-central Nevada

    NASA Astrophysics Data System (ADS)

    Bell, J. W.; Katzenstein, K.

    2012-12-01

    The Carlin trend in north-central Nevada has the second largest gold resources in the world, most of it produced from large open-pit mines. Heavy groundwater dewatering is required at the mines to lower water levels below the depth of mining which can exceed 400-500 m. The resulting water level declines have produced surface deformation (subsidence) that can be detected and modeled with InSAR to characterize the aquifer-system response and to estimate hydraulic parameters in order to test and refine groundwater models. In a series of studies we examined the effects of dewatering at mines operated by Newmont Mining Corporation and Barrick Gold of North America near Battle Mountain and Carlin, Nevada. The Lone Tree mine operated a large-scale dewatering program between 1992-2006 using deep bedrock wells that pumped between 64-92 hm3/yr (52,000-75,000 acre-ft/yr) and lowered bedrock water levels more than 120 m. InSAR analysis of ERS and Envisat data for the 1992-2000 and 2004-2010 periods showed that as much as 50 cm of aquifer-system compaction occurred in bedrock and in alluvial basin deposits with subsidence rates ranging between 3-6 cm/yr. Since dewatering ended in late 2006 and water levels began rising, only 7 cm of aquifer-system recovery (uplift) has occurred as of 2010 suggesting that most of the aquifer-system compaction was likely inelastic, apparently in the pumped fractured bedrock. The InSAR subsidence data differ significantly from the pre-pumping groundwater model which predicted 2.5 m of subsidence for the 1992-2000 period. The results yield bulk storage coefficients in the range of 7 x 10-3 to 5.6 x 10-5 with a most frequent value of 1.0 x 10-3 (Baffoe-Twum, 2007), InSAR-derived hydraulic values that can provide better constraints on specific storage estimates in future groundwater models. The Betze-Post mine has been dewatering continually since late 1989 with maximum pumping rates of greater than 140 hm3/yr (110,000 acre-ft/yr) in the early and late 1990s. This resulted in the lowering of groundwater levels by as much as 500 m in some areas. Analysis of InSAR data covering the 1992-2000 and 2004-2010 time periods suggests a cumulative measured subsidence magnitude of approximately 50 cm. In this case, all of the aquifer-system compaction is occurring in bedrock. Estimates of bulk storage coefficients at Betze-Post are also on the order of approximately 1.0 x 10-3 suggesting that subsidence at both sites is occurring in materials of similar character. Subsidence rates have decreased to near zero since groundwater production was reduced in the early 2000s. Since the early 2000s, subsidence rates resulting from dewatering at the neighboring Leeville mine have been greater than those at Betze-Post. Dewatering at the Turquoise Ridge-Twin Creeks and Gold Quarry mines, adjacent to these two larger mines, has also produced measureable aquifer-system compaction but with lower rates of subsidence. However, detailed hydrologic analyses have not been undertaken at these mines.

  14. Dewatering of the Clayton Formation during construction of the Walter F George Lock and Dam, Fort Gaines, Clay County, Georgia

    USGS Publications Warehouse

    Stewart, J.W.

    1973-01-01

    Walter F. George Lock and Dam, the largest manmade structure in the South, extends over 2llz miles across the flood plain of the Chattahoochee River at Fort Gaines, Clay County, in southwest Georgia and in Henry County, in southeast Alabama. The multipurpose dam consists of two rolled-filled earth dikes, a concrete spillway, a single-stage lock with an 88-foot lift, and a 130,000 kilowatt capacity powerhouse. The foundation of the dam at the river is constructed in the Clayton Formation, and the earth dikes are constructed on river terraces at about 150 feet above msl (mean sea level). At the damsite, the top of the Clayton Formation consists of an "earthy" limestone, which is about 35 feet thick except in the river channel, where it is 12 to 15 feet thick; a "shell" limestone, which averages about 40 feet thick; and a basal "sandy" limestone, which averages about 35 feet thick. The Providence Sand underlies the "sandy" limestone and its thickness is about 175 feet at the damsite. These formations contain water under artesian conditions. The "shell" unit of the Clayton was the principal water-bearing formation pumped during construction of the lock and dam. The large yields of the wells from concentrated areas over extended periods of time indicate that in the vicinity of the Chattahoochee River, the Clayton Formation is a productive aquifer with transmissivity ranging from 48,000 to 77,000 gpd per ft. (gallons per day per foot) and storage coefficient ranging from 2.5 x 10?3 to 2.8 x 10?5. At the spillway site, pumpage ranged from an average of 1,700 to 8,400 gpm (gallons per minute) during the period April 1957 to July 1959; at the powerhouse site, pumpage ranged from 1,600 to 5,000 gpm during the period October 1957 to September 1961; and at the lock site, pumpage ranged from 4,000 to 5,000 gpm during the period July 1960 through December 1961. The large yields represent a source of large quantities of ground water available for industrial and other uses in an area readily accessihle by barge from the Gulf of Mexico to Columbus, Ga. During dewatering, the potentiometric surface was lowered from a pre-pumping altitude of about 115 to 120 feet above msl to a minimum altitude of about 40 feet above msl, or near the bottom of the "shell" limestone. The stage of the Chattahoochee River ranged from about 20 to 60 feet above the potentiometric surface at the dewatering sites. The Chattahoochee River seemingly is recharging the Clayton Formation near the damsite, possibly through large solution cavities such as were observed during construction of the spillway site at the river. Furthermore, a "honeycombed" network of large solution holes caused the collapse of a section of "earthy" limestone near the powerhouse site. Some underground leakage is expected to occur at the damsite because of the cavernous condition of the limestone, particularly on the Alabama side of the river.

  15. Characterization of controlled low-strength material obtained from dewatered sludge and refuse incineration bottom ash: mechanical and microstructural perspectives.

    PubMed

    Zhen, Guangyin; Lu, Xueqin; Zhao, Youcai; Niu, Jing; Chai, Xiaoli; Su, Lianghu; Li, Yu-You; Liu, Yuan; Du, Jingru; Hojo, Toshimasa; Hu, Yong

    2013-11-15

    Potential reuse of dewatered sludge (DS) and municipal solid waste incineration (MSWI) bottom ash as components to develop controlled low-strength material (CLSM) was explored. The effects of DS:MSWI bottom ash:calcium sulfoaluminate (CS¯A) cement ratio and thermal treatment of MSWI bottom ash at 900 °C on the mechanical and microstructural properties of CLSM were intensively studied to optimize the process. Results showed DS and MSWI bottom ash could be utilized for making CLSM. The CLSM prepared with milled MSWI bottom ash gave higher unconfined compressive strength (UCS) of 2.0-6.2 MPa following 1 year of curing at 1.0:0.1:0.9 ? DS:MSWI bottom ash:CS¯A ? 1.0:0.8:0.2. However, the corresponding strengths for CLSM containing thermally treated MSWI bottom ash ranged from 0.7 to 4.6 MPa, decreasing 26-65%. The microstructural analysis by X-ray powder diffraction (XRD), Fourier transforms infrared spectroscopy (FT-IR), as well as scanning electron microscopy (SEM) combined with an energy dispersive X-ray spectroscopy (EDS) revealed that ettringite (C3A·3CS¯·H32, or AFt) crystals were the most important strength-producing constituents which grew into and filled the CLSM matrix pores. Milled MSWI bottom ash addition favored the formation of highly crystalline AFt phases and accordingly enhanced compressive strengths of CLSM specimens. In contrast, thermal treatment at 900 °C produced new phases such as gehlenite (Ca2Al2SiO7) and hydroxylapatite (Ca5(PO4)3(OH)), which deteriorated the pozzolanic activity of bottom ash and caused the strengths to decrease. Leaching tests evidenced that leachable substances from CLSM samples exhibited negligible health and environmental risks. The results of this study suggested that MSWI bottom ash can be effectively recycled together with DS in developing CLSM mixtures with restricted use of CS¯A cement. PMID:23933484

  16. Addition of polyaluminiumchloride (PACl) to waste activated sludge to mitigate the negative effects of its sticky phase in dewatering-drying operations.

    PubMed

    Peeters, Bart; Dewil, Raf; Vernimmen, Luc; Van den Bogaert, Benno; Smets, Ilse Y

    2013-07-01

    This paper presents a new application of polyaluminiumchloride (PACl) as a conditioner for waste activated sludge prior its dewatering and drying. It is demonstrated at lab scale with a shear test-based protocol that a dose ranging from 50 to 150 g PACl/kg MLSS (mixed liquor suspended solids) mitigates the stickiness of partially dried sludge with a dry solids content between 25 and 60 %DS (dry solids). E.g., at a solids dryness of 46% DS the shear stress required to have the pre-consolidated sludge slip over a steel surface is reduced with 35%. The salient feature of PACl is further supported by torque data from a full scale decanter centrifuge used to dewater waste sludge. The maximal torque developed by the screw conveyor inside the decanter centrifuge is substantially reduced with 20% in the case the sludge feed is conditioned with PACl. The beneficial effect of waste sludge conditioning with PACl is proposed to be the result of the bound water associated with the aluminium polymers in PACl solutions which act as a type of lubrication for the intrinsically sticky sludge solids during the course of drying. It can be anticipated that PACl addition to waste sludge will become a technically feasible and very effective method to avoid worldwide fouling problems in direct sludge dryers, and to reduce torque issues in indirect sludge dryers as well as in sludge decanter centrifuges. PMID:23726696

  17. Western oil-shale development: a technology assessment. Volume 5: an investigation of dewatering for the modified in-situ retorting process, Piceance Creek Basin, Colorado

    SciTech Connect

    Not Available

    1982-01-01

    The C-a and the C-b tracts in the Piceance Creek Basin are potential sites for the development of oil shale by the modified in-situ retorting (MIS) process. Proposed development plans for these tracts require the disturbance of over three billion m/sup 3/ of oil shale to a depth of about 400 m (1312 ft) or more below ground level. The study investigates the nature and impacts of dewatering and reinvasion that are likely to accompany the MIS process. The purpose is to extend earlier investigations through more refined mathematical analysis. Physical phenomena not adequately covered in previous studies, particularly the desaturation process, are investigated. The present study also seeks to identify, through a parametric approach, the key variables that are required to characterize systems such as those at the C-a and C-b tracts.

  18. Migration and distribution of water and organic matter for activated sludge during coupling magnetic conditioning-horizontal electro-dewatering (CM-HED).

    PubMed

    Qian, Xu; Wang, Yili; Zheng, Huaili

    2016-01-01

    Magnetic micro-particles (MMPs) and magnetic field (MF) were utilized as a coupling conditioning unit before dewatering activated sludge (AS) under a horizontal electric field. The removal and migration of free and bound water in AS during coupling magnetic conditioning-horizontal electro-dewatering (CM-HED) were determined. The organic matter migration between the solid and liquid phases of AS biosolids was also analyzed. Results show that MMPs dosage and MF intensity were determined as 0.15 g/g dry solids and 0.065 T for the best dewaterability, respectively. The optimum dewatering conditions for CM-HED with the final water content of 89.98% were 40 V and 120 min as determined using the response surface methodology. MMPs conditioning could induce a slight coagulation among AS flocs, increase the particle size from 85.9 ?m to 92.3 ?m and decrease mass fractal dimension from 2.18 to 2.07. The MMPs-conditioned AS also showed a network-like structure, banded cells with shrunk surfaces. CM-HED process effectively reduced the free water content (FWC) and bound water content (BWC) but increased the portion of BWC in AS. The corresponding removal ratios of bound water and free water were 52.89% and 95.86% at the anode side and 46.28% and 92.75% at the cathode side, respectively. The coupling magnetic conditioning led to the largest BWC reduction of 23.14% in CM-HED process, and most of this reduction approaching 92.83% occurred during magnetic micro-particle conditioning stage. Gravity field caused the largest sludge reduction of 87.45%. During HED stage, the removal ratio of free water in AS was 63.73% at the anode side and 36.54% at the cathode side, while it was 21.9% and 10.96% for bound water, respectively. Along with water removed by CM-HED process, the organic matter in supernatant/filtrate increased, and a sharp rise occurred during HED stage. Meanwhile, the extracellular polymeric substance (EPS) contents initially decreased at MMPs-MF conditioning stage and then increased at the HED stage. Lower EPS contents in AS indicated better dewaterability. The largest reduction in the EPS content of AS at MMPs-MF conditioning stage corresponded to the largest decline in BWC. Furthermore, the protein-like substances in the supernatant/filtrate increased from 30% to 50%, whereas the fulvic acid-like and humic acid-like substances decreased from 54% to 27% at the HED stage. MMPs significantly reduced the polysaccharide and protein contents in the slime-EPS by 90.26% and 99.25%, respectively. Approximately 92.35% of humic acid-like materials in tightly bound EPS were reduced by MMPs. Thus, coupling magnetic conditioning should be selected as pretreatment prior to HED. PMID:26476680

  19. Dissipation of triclosan, triclocarban, carbamazepine and naproxen in agricultural soil following surface or sub-surface application of dewatered municipal biosolids.

    PubMed

    Al-Rajab, Abdul Jabbar; Sabourin, Lyne; Lapen, David R; Topp, Edward

    2015-04-15

    In many jurisdictions land application of municipal biosolids is a valued source of nutrients for crop production. The practice must be managed to ensure that crops and adjacent water are not subject to contamination by pharmaceuticals or other organic contaminants. The broad spectrum antimicrobial agents triclosan (TCS) and triclocarban (TCC), the anti-epileptic drug carbamazepine (CBZ), and the nonsteroidal anti-inflammatory drug naproxen (NAP) are widely used and are carried in biosolids. In the present study, the effect of biosolids and depth of placement in the soil profile on the rates of TCS, TCC, CBZ, and NAP dissipation were evaluated under semi-field conditions. Aggregates of dewatered municipal biosolids (DMBs) supplemented with (14)C-labeled residues were applied either on the soil surface or in the subsurface of the soil profile, and incubated over several months under ambient outdoor conditions. The dissipation of TCS, TCC and NAP was significantly faster in sub-surface than surface applied biosolid aggregates. In contrast the dissipation rate for CBZ was the same in surface applied and incorporated aggregates. Overall, the present study has determined a significant effect of depth of placement on the dissipation rate of biodegradable molecules. PMID:25644844

  20. Effects of seepage from fly-ash settling ponds and construction dewatering on ground-water levels in the Cowles unit, Indiana Dunes National Lakeshore, Indiana

    USGS Publications Warehouse

    Meyer, William R.; Tucci, Patrick

    1979-01-01

    Part of the Indiana Dunes National Lakeshore shares a common boundary with the Northern Indiana Public Service Company (NIPSCO). This area is underlain by unconsolidated deposits approximately 180 feet thick. NIPSCO accumulates fly ash from the burning of coal in electric-power generating units in settling ponds. Seepage from the ponds has raised ground-water levels above natural levels approximately 15 feet under the ponds and more than 10 feet within the Lakeshore. NIPSCO is presently (1977) constructing a nuclear powerplant, and construction activities include pumping ground water to dewater the construction site. The company has installed a slurry wall around the site to prevent lowering of ground-water levels within the Lakeshore. Plans call for continuous pumping through at least December 1979. A multilayered digital flow model was constructed to simulate the ground-water system. The model was used to demonstrate the effects of seepage from the fly-ash ponds on ground-water levels. Also, the model indicated a decline of 3 feet or less in the upper sand unit and 5 feet or less in the lower sand unit within the Lakeshore. (Woodard-USGS).

  1. Extending the use of dewatered alum sludge as a P-trapping material in effluent purification: Study on two separate water treatment sludges.

    PubMed

    Zhao, Y Q; Yang, Y

    2010-08-01

    The generation of alum sludge from drinking water purification process remains inevitable when aluminium sulphate is used as primary coagulant for raw water coagulation. Sustainable managing such the sludge becomes an increasing concern in water industry. Its beneficial reuse is therefore highly desirable and has attracted considerable research efforts. In view of the novel development of alum sludge as a value-added raw material for beneficial reuse for wastewater treatment, this study examined the maximum phosphorus-adsorption capacity of two dewatered alum sludges sampled from two largest water treatment works in Dublin, Ireland. The objective lies in clarifying the change of alum sludge characteristics and its P-adsorption capacity over the location of the alum sludge produced and the raw water being treated. Experiments have demonstrated that the two alum sludges have the similar P adsorption capacity (14.3 mg P/g sludge for Ballymore-Eustace sludge and 13.1 mg P/g sludge for Leixlip sludge at pH 7.0). However, the study supports that alum sludge beneficial reuse as a low cost adsorbent for P immobilization should study its P-adsorption capacity before any decision of large application is made since the raw water quality will affect the sludge characteristics and therefore influence its adsorption ability. PMID:20623402

  2. Effects of Fe(II) and Fe(III) on the single-stage deammonification process treating high-strength reject water from sludge dewatering.

    PubMed

    Liu, Sitong; Horn, Harald

    2012-06-01

    Iron (Fe) is often encountered in wastewaters. This study investigated the effects of iron on the single-stage deammonification process treating reject water from sludge dewatering. When Fe(2+) and Fe(3+) concentrations in the influent were below 1.3mg/L and 0.4 mg/L, Fe(2+) incorporation was found to be linearly correlated with NH(4)(+)-N removal. However, the excess Fe(2+) and Fe(3+) drastically deteriorated the deammonification performance. Both of the reactor performance and Fluorescence In Situ Hybridization results suggested higher sensitivity of autotrophic bacteria to iron than heterotrophs, the sequence of which was assessed to anammox bacteria>aerobic ammonium oxidizers>hetetrophic denitrifiers. With the excess existence of iron, extracellular substances were largely released by bacterial cells, which were the likely sites for iron uptake by scanning electron microscope-energy dispersive X-ray analysis. The information provided here would be useful to facilitate the application of deammonification process in the treatment of wastewater including metal iron. PMID:22483570

  3. Ground-water levels, water quality, and potential effects of toxic-substance spills or cessation of quarry dewatering near a municipal ground-water supply, southeastern Franklin County, Ohio

    USGS Publications Warehouse

    Sedam, A.C.; Eberts, S.M.; Bair, E.S.

    1989-01-01

    A newly completed municipal ground-water supply that produces from a sand and gravel aquifer in southern Franklin County, Ohio, may be susceptible to potential sources of pollution. Among these are spills of toxic substances that could enter recharge areas of the aquifer or be carried by surface drainage and subsequently enter the aquifer by induced infiltration. Ground water of degraded quality also is present in the vicinity of several landfills located upstream from the municipal supply. Local dewatering by quarrying operations has created a ground-water divide which, at present, prevents direct movement of the degraded ground water to the municipal supply. In addition, the dewatering has held water levels at the largest landfills below the base of the landfill. Should the dewatering cease, concern would be raised regarding the rise of water levels at this landfills and transport of contaminants through the aquifer to the Scioto River and subsequently by the river to the well field. From June 1984 through July 1986, the U.S. Geological Survey, in cooperation with the City of Columbus, Ohio, investigated the relations among the ground-water supply and potential sources of contamination by means of an observation-well network and a program of measuring water levels and sampling for water quality. Sample collections included those made to determine the baseline levels of organic chemicals and metals, as well as periodic sampling and analysis for common constituents to evaluate any changes taking place in the system. Finally, a steady-state, three-dimensional numerical model was used to determine ground-water flow directions and average ground-water velocities to asses potential effects of toxic-substance spills. The model also was used to simulate changes in the ground-water flow system that could result if part or all of the quarry dewatering ceased. Few of the organic-chemical and metal constituents analyzed for were present at detectable levels. With respect to chemical analysis of water and soil materials reported in earlier studies, no new problem areas were discovered as a result of either the baseline or periodic samplings. Model simulations suggest that, under March 1986 conditions, a toxic-substance spill along the major highways in the northern two-thirds of the study area eventually could discharge into one of the two quarries being dewatered or into the Scioto River. A toxic-substance spill in the southern one-third of the study area ultimately may discharge into the Scioto River, Big Walnut Creek, or possibly into the municipal ground-water supply. Model simulations also indicate that concentrated landfill leachate probably would not reach the municipal ground-water supply under current or well-field pumping conditions if dewatering ceased at either or both of the quarries.

  4. Bench-scale testing of DOE/PETC`s GranuFlow Process for fine coal dewatering and handling. 1: Results using a high-gravity solid-bowl centrifuge

    SciTech Connect

    Wen, W.W.; Killmeyer, R.P.; Lowman, R.H.; Elstrodt, R.

    1995-12-31

    Most advanced fine-coal cleaning processes involve the use of water. Utility companies are concerned not only with the lower Btu content of the resulting wet, cleaned coal, but more importantly with its handleability problems. Solutions to these problems would enhance the utilization of fine-coal cleaning processes in the utility industry. This paper describes testing of the GranuFlow Process, developed and patented by the Pittsburgh Energy Technology Center (PETC) of the US Department of Energy, using a high-gravity solid bowl centrifuge for dewatering and reconstitution of fine-cleaned-coal slurry at 300 lb per hour in PETC`s Coal Preparation Process Research Facility. Fine-cleaned-coal slurry was treated with a bitumen emulsion before dewatering in a high-gravity solid-bowl centrifuge. The treated products appeared to be dry and in a free-flowing granular form, while the untreated products were wet, lumpy, sticky, and difficult to handle. Specifically, test results indicated that the moisture content, handleability, and dust reduction of the dewatered coal product improved as the addition of emulsion increased from 2% to 8%. The improvement in handleability was most visible for the 200 mesh (75 micron) x 0 coal, when compared with 150 mesh (106 micron) x 0, 65 mesh (212 micron) x 0 or 28 mesh (600 micron) x 0 coals. Test results also showed that the moisture content was dramatically reduced (26--37% reduction) for the four different sizes of coals at 6 or 8% emulsion addition. Because of the moisture reduction and the granular form of the product, the freezing problem was also alleviated.

  5. Sreambank Dewatering for Increased Stability

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Streambank erosion is often the dominant source of sediment leaving watersheds disturbed by human activities. Collapse of high, steep banks is one of the most serious forms of streambank erosion. The risk of a given bank experiencing mass failure is a function of bank height, angle, and soil streng...

  6. Clastic-hosted stratiform, vein/breccia and disseminated Zn-Pb-Ag deposits of the northwestern Brooks Range, AK: Are they different expressions of dewatering of the same source basin

    SciTech Connect

    Schmidt, J.M. ); Werdon, M.B. . Dept. of Geology)

    1993-04-01

    Sphalerite and galena, with significant silver occur in 3 distinct types of mineralization hosted in Upper Devonian and Carboniferous clastic rocks of the northwestern Brooks Range. The best known are Zn-Pb-Ag massive sulfide deposits with variable pyrite, barite, and hydrothermal silifica hosted in Mississippian (to Pennsylvanian ) black siliceous shale and chert, and similar to shale-hosted Pb-Zn massive sulfide deposits worldwide. Zn-Pb-Ag breccias and veins are hosted in Upper Devonian to Lower Mississippian fine-grained quartzites and siltstone which stratigraphically underlie the massive sulfide-hosting units. The breccia-vein and disseminated occurrences are co-extensive with the rocks that host massive sulfide deposits, and with the western part of the Endicott Group clastic basin. Pb isotopic ratios of galena from all the deposits are remarkably uniform, and suggest a single Pb source. The authors genetic model suggests that all types are the result of dewatering of a single clastic source basin. Different mineralization styles are probably due to variable depths of emplacement (at or below the seafloor), thermal variations related to extensional thinning of the crust, and hydrologic flow out of the basin controlled by extensional thinning of the crust, and hydrologic flow out of the basin controlled by extensional faulting and permeability variations in local stratigraphy. The most likely sources for Zn and Pb are clay minerals within the lowermost (Hunt Fork Shale) portions of the western Endicott Group.

  7. A MECHANISM FOR ASH ASSISTED SLUDGE DEWATERING

    EPA Science Inventory

    The ability of various additives to improve the dewaterability of activated sludge was determined and the surface properties of additives characterized in order to arrive at a mechanism for ash conditioning of activated sludge. The primary additives investigated were fly ash and ...

  8. ACOUSTIC FORMING FOR ENHANCED DEWATERING AND FORMATION

    SciTech Connect

    Cyrus K Aidun

    2007-11-30

    The next generation of forming elements based on acoustic excitation to increase drainage and enhances formation both with on-line control and profiling capabilities has been investigated in this project. The system can be designed and optimized based on the fundamental experimental and computational analysis and investigation of acoustic waves in a fiber suspension flow and interaction with the forming wire.

  9. Sewage sludge dewatering using flowing liquid metals

    DOEpatents

    Carlson, Larry W. (Oswego, IL)

    1986-01-01

    A method and apparatus for reducing the moisture content of a moist sewage sludge having a moisture content of about 50% to 80% and formed of small cellular micro-organism bodies having internally confined water is provided. A hot liquid metal is circulated in a circulation loop and the moist sewage sludge is injected in the circulation loop under conditions of temperature and pressure such that the confined water vaporizes and ruptures the cellular bodies. The vapor produced, the dried sludge, and the liquid metal are then separated. Preferably, the moist sewage sludge is injected into the hot liquid metal adjacent the upstream side of a venturi which serves to thoroughly mix the hot liquid metal and the moist sewage sludge. The venturi and the drying zone after the venturi are preferably vertically oriented. The dried sewage sludge recovered is available as a fuel and is preferably used for heating the hot liquid metal.

  10. In focus: Dewatering. [Use of ceramic filters for dewatering mine slurries as wastes

    SciTech Connect

    Rantala, P.

    1994-09-01

    A process filter whose operation is based on a simple hydrostatics phenomenon that is taught in school physics classes is able to improve the productivity of process plant, reduce equipment space and complexity, improve the plant environment and reduce overall processing costs. The author gives an overview of his company's capillary filtration technology and Engineering Editor Nick Horton describes how it works, with information and diagrams courtesy of Outokumpu Mintec.

  11. Method of waste stabilization with dewatered chemically bonded phosphate ceramics

    DOEpatents

    Wagh, Arun; Maloney, Martin D.

    2010-06-29

    A method of stabilizing a waste in a chemically bonded phosphate ceramic (CBPC). The method consists of preparing a slurry including the waste, water, an oxide binder, and a phosphate binder. The slurry is then allowed to cure to a solid, hydrated CBPC matrix. Next, bound water within the solid, hydrated CBPC matrix is removed. Typically, the bound water is removed by applying heat to the cured CBPC matrix. Preferably, the quantity of heat applied to the cured CBPC matrix is sufficient to drive off water bound within the hydrated CBPC matrix, but not to volatalize other non-water components of the matrix, such as metals and radioactive components. Typically, a temperature range of between 100.degree. C.-200.degree. C. will be sufficient. In another embodiment of the invention wherein the waste and water have been mixed prior to the preparation of the slurry, a select amount of water may be evaporated from the waste and water mixture prior to preparation of the slurry. Another aspect of the invention is a direct anyhydrous CBPC fabrication method wherein water is removed from the slurry by heating and mixing the slurry while allowing the slurry to cure. Additional aspects of the invention are ceramic matrix waste forms prepared by the methods disclosed above.

  12. COMPOSTING: STABILIZATION, DEWATERING, VOLUME REDUCTION, AND PATHOGEN KILL

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aerobic composting is the biological oxidative decomposition of organic materials by successive communities of microorganisms under different temperature regimes which produces a humified end-product. Composting reduces moisture content of organic byproducts. Thermophilic temperatures attained dur...

  13. The ABCs of pump selection for mine dewatering

    SciTech Connect

    Morgan, S.E.

    2008-10-15

    Choosing the right type of pump for removing water from mine operations can provide significant benefits in overall performance and cost of operation. The article describes the types of pump most commonly used: vertical turbine pumps, electric and hydraulic submersible pumps, horizontal multistage centrifugal pumps and horizontal single-stage centrifugal pumps. It gives points to consider when selecting a suitable pump, including solids handling capacity and acid content, portability, automatic operation, easy maintenance and parts availability. 1 photo.

  14. AUTOMATION OF SLUDGE PROCESSING: CONDITIONING, DEWATERING, AND INCINERATION

    EPA Science Inventory

    The study developed and tested automated control strategies for municipal wastewater sludge processing. The strategies consisted of chemical conditioning vacuum filtration and incineration. The project was conducted at the St. Paul, Minnesota Metropolitan Waste Control Commission...

  15. DEWATERING OF DILUTE AQUEOUS HAZARDOUS WASTES USING REVERSIBLE GEL ABSORPTION

    EPA Science Inventory

    The feasiability of using crosslinked gels in a reversible process for extracting pure water from aqueous waste solutions has been investigated. It has potential for concentrating waste streams that contain hazardous chemicals. Near critical gels have been developed which swell a...

  16. INCREASE OF INDICATOR ORGANISMS FOLLOWING ANAEROBIC DIGESTION AND CENTRIFUGE DEWATERING.

    EPA Science Inventory

    The Water Environment Research Foundation (WERF) recently published a report titled “Examination of Reactivation and Regrowth of Fecal Coliforms in Anaerobically Digested Sludges”. Seven full-scale publicly owned treatment facilities were sampled several times to determine if bac...

  17. Relationship of shale dewatering and smectite dehydration to undercompaction occurrence

    SciTech Connect

    Leftwich, J.T. Jr.

    1996-12-01

    The cause(s) of abnormal fluid pressures in sedimentary basins are not clearly understood. One step in determining the mechanism(s) of abnormal pressure generation in sedimentary basins is to develop an understanding of the relationship among undercompacted shale, abnormal pressure, and temperature. Our research focused on understanding undercompaction and how it related to smectite-illite conversion. A series of carefully designed experiments were used to help clarify and evaluate the relationship of smectite-illite transformation to undercompaction.

  18. Minimizing the energy requirement of dewatering scenedesmus sp. by microfiltration: performance, costs, and feasibility.

    PubMed

    Gerardo, Michael L; Oatley-Radcliffe, Darren L; Lovitt, Robert W

    2014-01-01

    The harvesting of the microalgae Scenedesmus species using a 200 L pilot-scale microfiltration system was investigated and critically assessed. The energy requirement was determined and correlated to the different operating parameters, such as transmembrane pressure (?P), membrane area, temperature, and initial biomass concentration. A filtration model was developed and showed a strong correlation with experimental data up to 20.0 g of dry cell weight (DCW)/L. The non-optimized filtration system had an energy requirement of 2.23 kWh/m(3) with an associated cost of $0.282/kg of microalgae. The investigation into the influence of the operating parameters and scale-up effects showed that the energy requirement could be substantially reduced to 0.90 kWh/m(3) and $0.058/kg of microalgae harvested. Maintenance costs associated with cleaning were estimated to be 0.23 kWh or $0.029/batch of microalgae processed. Dependent upon the operating conditions, harvesting may represent 6-45% of the energy embedded in the microalgae with a carbon footprint of 0.74-1.67 kg of CO2/kg of microalgae. Microfiltration was demonstrated to be a feasible microalgae harvesting technology allowing for more than 99% volume reduction. The energy requirement and associated carbon footprint of microalgae harvesting reported here do not forfeit the need for an industrial-scale study; however, the information provided presents a more realistic approximation than the literature reported to date. PMID:24341825

  19. Method and apparatus for de-watering biomass materials in a compression drying process

    DOEpatents

    Haygreen, John G. (Roseville, MN)

    1986-01-01

    A method and apparatus for more effectively squeezing moisture from wood chips and/or other "green" biomass materials. A press comprising a generally closed chamber having a laterally movable base at the lower end thereof, and a piston or ram conforming in shape to the cross-section of the chamber is adapted to periodically receive a charge of biomass material to be dehydrated. The ram is forced against the biomass material with suffcient force to compress the biomass and to crush the matrix in which moisture is contained within the material with the face of the ram being configured to cause a preferential flow of moisture from the center of the mass outwardly to the grooved walls of the chamber. Thus, the moisture is effectively squeezed from the biomass and flows through the grooves formed in the walls of the chamber to a collecting receptacle and is not drawn back into the mass by capillary action when the force is removed from the ram.

  20. REDUCING RIVERBANK RETREAT RATES BY DE-WATERING USING LOW COST SUBMERSIBLE PUMPS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bank retreat due to mass failure causes the loss of thousands of hectares of land every year in the US and elsewhere, and is a major source of sediment and contaminants in rivers and streams. A self-contained and low-cost submersible pump system has been tested in a section of incised streambank in...

  1. Hexavalent chromium waste detoxified by chemical system, dewatered through filter press

    SciTech Connect

    Not Available

    1984-09-01

    In the manufacture of aluminum parts and components at Gables Engineering Incorporated of Coral Gables, Florida, disposal of a waste solution containing Cr(VI) presents great disposal problems. Treatment of the solution of Cr(VI) with H/sub 2/SO/sub 4/ reduces the pH to 2 and with sodium bisulfate reduces the Cr(VI) to Cr(III). Caustic soda is then added to precipitate the Cr(III) and other metals as hydroxides; a polymeric flocculation agent is added; and the solids are removed by filtration. The filter cake is delegated to an outside contractor for disposal in a clay-lined secure landfill. This process results in a degree of purity of the waste water to allow its disposal to the local water district.

  2. Evaluation of Ferrate(VI) as an Conditioner for Dewatering Wastewater Biosolids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Land application of sludge/biosolids is a commonly used practice for final utilization. Therefore, adequate conditioning and stabilization of wastewater solids is very critical for safe land application. The addition of ferrate (FeO42-) has the potential to improve the dewaterbility of solids, des...

  3. Extending shelf-life of ready-to-eat microgreens by optimizing dewatering procedure

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Microgreens have gained increasing popularity as food ingredients in recent years, because of their high nutritional value, as well as their abundant, diverse, and distinct sensorial characteristics including a variety of fresh flavors and aromas and vivid colors. However, their commercial productio...

  4. Dewatering Treatment Scale-up Testing Results of Hanford Tank Wastes

    SciTech Connect

    Tedeschi, A.R.; May, T.H.; Bryan, W.E.

    2008-07-01

    This report documents CH2M HILL Hanford Group Inc. (CH2M HILL) 2007 dryer testing results in Richland, WA at the AMEC Nuclear Ltd., GeoMelt Division (AMEC) Horn Rapids Test Site. It provides a discussion of scope and results to qualify the dryer system as a viable unit-operation in the continuing evaluation of the bulk vitrification process. A 10,000 liter (L) dryer/mixer was tested for supplemental treatment of Hanford tank low activity wastes, drying and mixing a simulated non-radioactive salt solution with glass forming minerals. Testing validated the full scale equipment for producing dried product similar to smaller scale tests, and qualified the dryer system for a subsequent integrated dryer/vitrification test using the same simulant and glass formers. The dryer system is planned for installation at the Hanford tank farms to dry/mix radioactive waste for final treatment evaluation of the supplemental bulk vitrification process. (authors)

  5. Modeling consolidation and dewatering near the toe of the northern Barbados accretionary complex

    USGS Publications Warehouse

    Stauffer, P.; Bekins, B.A.

    2001-01-01

    At the toe of the northern Barbados accretionary complex, temperature and pore water chemistry data indicate that fluid flow is channeled along the de??collement and other shallow thrust faults. We examine mechanisms that may prevent consolidation and maintain high permeability over large sections of the de??collement. High-resolution bulk density data from five boreholes show that the de??collement is well consolidated at some sites while other sites remain underconsolidated. Underconsolidated de??collement behavior is associated with kilometer-scale negative-polarity seismic reflections from the de??collement plane that have been interpreted to be fluid conduits. We use a coupled fluid flow/consolidation model to simulate the loading response of a 10-km-long by 680-m-thick slice of sediment as it enters the accretionary complex. The simulations capture 185 ka (5 km) of subduction, with a load function representing the estimated effective stress of the overriding accretionary prism (3.8?? taper angle). Simulation results of bulk density in the de??collement 3.2 km arcward of the deformation front are compared with observations. The results show that persistent high pore pressures at the arcward edge of the simulation domain can explain underconsolidated behavior. The scenario is consistent with previous modeling results showing that high pore pressures can propagate intermittently along the de??collement from deeper in the complex. Simulated seaward fluxes in the de??collement (1-14 cm yr-1) lie between previous estimates from modeling studies of steady state (1 m yr-1) flow. Maximum simulated instantaneous fluid sources (2.5??10-13 s-1) are comparable to previous estimates. The simulations show minor swelling of incoming sediments (fluid sources ??? -3 ?? 1015 s-1) up to 3 km before subduction that may help to explain small-scale shearing and normal faulting proximal to the protode??collement. Copyright 2001 by the American Geophysical Union.

  6. Direct molecular diffusion and micro-mixing for rapid dewatering of LiBr solution

    SciTech Connect

    Bigham, S; Isfahani, RN; Moghaddam, S

    2014-03-01

    A slow molecular diffusion rate often limits the desorption process of an absorbate molecule from a liquid absorbent. To enhance the desorption rate, the absorbent is often boiled to increase the liquid vapor interfacial area. However, the growth of bubbles generated during the nucleate boiling process still remains mass-diffusion limited. Here, it is shown that a desorption rate higher than that of boiling can be achieved, if the vapor absorbent interface is continuously replenished with the absorbate-rich solution to limit the concentration boundary layer growth. The study is conducted in a LiBr-water-solution, in which the water molecules' diffusion rate is quite slow. The manipulation of the vapor solution interface concentration distribution is enabled by the mechanical confinement of the solution flow within microchannels, using a hydrophobic vapor-venting membrane and the implementation of microstructures on the flow channel's bottom wall. The microstructures stretch and fold the laminar streamlines within the solution film and produce vortices. The vortices continuously replace the concentrated solution at the vapor solution interface with the water-rich solution brought from the bottom and middle of the flow channel. The physics of the process is described using a combination of experimental and numerical studies. Published by Elsevier Ltd.

  7. DEWATERING TREATMENT SCALE-UP TESTING RESULTS OF HANFORD TANK WASTES

    SciTech Connect

    TEDESCHI AR

    2008-01-23

    This report documents CH2M HILL Hanford Group Inc. (CH2M HILL) 2007 dryer testing results in Richland, WA at the AMEC Nuclear Ltd., GeoMelt Division (AMEC) Horn Rapids Test Site. It provides a discussion of scope and results to qualify the dryer system as a viable unit-operation in the continuing evaluation of the bulk vitrification process. A 10,000 liter (L) dryer/mixer was tested for supplemental treatment of Hanford tank low-activity wastes, drying and mixing a simulated non-radioactive salt solution with glass forming minerals. Testing validated the full scale equipment for producing dried product similar to smaller scale tests, and qualified the dryer system for a subsequent integrated dryer/vitrification test using the same simulant and glass formers. The dryer system is planned for installation at the Hanford tank farms to dry/mix radioactive waste for final treatment evaluation of the supplemental bulk vitrification process.

  8. Photoinitiated Polymerization of Cationic Acrylamide in Aqueous Solution: Synthesis, Characterization, and Sludge Dewatering Performance

    PubMed Central

    Zheng, Huaili; Liao, Yi; Zheng, Meizhen; Zhu, Chuanjun; Ji, Fangying; Ma, Jiangya; Fan, Wei

    2014-01-01

    A copolymer of acrylamide (AM) with acryloyloxyethyl trimethyl ammonium chloride (DAC) as the cationic monomer was synthesized under the irradiation of high-pressure mercury lamp with 2,2-azobis(2-amidinopropane) dihydrochloride (V-50) as the photoinitiator. The compositions of the photoinduced copolymer were characterized by Fourier transform infrared spectra (FTIR), ultraviolet spectra (UV), and scanning electron microscope (SEM). The effects of 6 important factors, that is, photo-initiators concentration, monomers concentration, CO(NH2)2 (urea) concentrations, pH value, mass ratio of AM to DAC, and irradiation time on the molecular weight and dissolving time, were investigated. The optimal reaction conditions were that the photo-initiators concentration was 0.3%, monomers concentration was 30?wt.%, irradiation time was 60 min, urea concentration was 0.4%, pH value was 5.0, and mass ratio of AM to DAC was 6?:?4. Its flocculation properties were evaluated with activated sludge using jar test. The zeta potential of supernatant at different cationic monomer contents was simultaneously measured. The results demonstrated the superiority of the copolymer over the commercial polyacrylamide as a flocculant. PMID:24683343

  9. Physics of lithium bromide (LiBr) solution dewatering through vapor venting membranes

    SciTech Connect

    Isfahani, RN; Fazeli, A; Bigham, S; Moghaddam, S

    2014-01-01

    The physics of water desorption from a lithium bromide (LiBr) solution flow through an array of microchannels capped by a porous membrane is studied. The membrane allows the vapor to exit the flow and retains the liquid. Effects of different parameters such as wall temperature, solution and vapor pressures, and solution mass flux on the desorption rate were studied. Two different mechanisms of desorption are analyzed. These mechanisms consisted of: (1) direct diffusion of water molecules out of the solution and their subsequent flow through the membrane and (2) formation of water vapor bubbles within the solution and their venting through the membrane. Direct diffusion was the dominant desorption mode at low surface temperatures and its magnitude was directly related to the vapor pressure, the solution concentration, and the heated wall temperature. Desorption at the boiling regime was predominantly controlled by the solution flow pressure and mass flux. Microscale visualization studies suggested that at a critical mass flux, some bubbles are carried out of the desorber through the solution microchannels rather than being vented through the membrane. Overall, an order of magnitude higher desorption rate compare to a previous study on a membrane-based desorber was achieved. Published by Elsevier Ltd.

  10. Pore-filling cements in turbidites; Southern California: Products of early diagenesis and dewatering of shale

    NASA Astrophysics Data System (ADS)

    Krystinik, L. F.

    Cementation of deep sea fan deposits which begins at the sediment water interface and continues progressively to the maximum depths was studied. The type and intensity of cementation is determined, in part, by the labile components within the system. Authigenic iron-rich smectite (AIRS) is the earliest cement in deep sea sediment. Formation of AIRS begins with the dissolution of biogenic silica. The Stevens sand provides insight into the early stages of graywacke formation. A significant volume of nondetrital, nonpseudomatrix clay is generated by precipitation of dissolved species carried into a sandstone body by waters expelled from adjacent shale. The Stevens also provides insight into turbidite sedimentation within a restricted basin supplied by several sediment sources. Most Cenozoic turbidities from southern California contain either calcite cement which occludes porosity and preserves the initial character of the sediment, or a silica clay cement which reduces porosity slightly, but occludes permeability. Cementation of sandstones by clays precipitated from pore fluids generated in adjacent shales may be a first step toward the genesis of graywacke.

  11. A method for detecting dewatering effects of underground mining activities on surface wetlands

    SciTech Connect

    Hayden-Wing, L.D.; Baldwin, J.R.; Webber, K.; Winstead, J.B.

    1999-07-01

    In 1996 US Energy/Kennecott Uranium Company initiated a large-scale, long-term monitoring program to document whether or not proposed uranium mining activities under Green Mountain in Central Wyoming would cause a groundwater draw-down resulting in changes in the existing riparian/wetland habitats. The monitoring program consisted of establishing 12 study drainages on Green Mountain and six control drainages on an adjacent but hydrologically isolated mountain not scheduled for mining. Baseline data were collected in 1996 and 1997 prior to the commencement of mining. For each drainage, breeding bird densities (birds/km) and richness (species/km), winter wild ungulate fecal pellet group densities (groups/km), small mammal densities (captures/trap night), and density and species composition of aquatic macro invertebrates were measured along permanent, marked transects within each riparian zone. In order to characterize the baseline vegetation and isolate the effects of livestock grazing, species composition, percent cover, production, and type boundary delineation of riparian vegetation were quantified within adjacent fenced and unfenced half-acre sample sites within each drainage. Baseline photographs were taken at permanent marked points from fixed angles at each of the sample sites. Piezometer holes were drilled at each monitoring site for measuring potential changes in ground water levels over time. If, during mining, water levels are found to drop significantly from baseline, a new study of wildlife and vegetative parameters would be conducted to determine whether or not significant decreases in wetland function or changes from baseline characteristics have occurred.

  12. Relationship of shale dewatering and smectite dehydration to undercompaction occurrence. Final report, October 1995--September 1996

    SciTech Connect

    Leftwich, J.T. Jr.

    1996-12-01

    The cause(s) of abnormal fluid pressures in sedimentary basins are not clearly understood. One step in determining the mechanism(s) of abnormal pressure generation in sedimentary basins is to develop and understanding of the relationship among undercompacted shale, abnormal pressure, and temperature. The research focused on understanding undercompaction and how it related to smectite-illite conversion. A series of carefully designed experiments were used to help clarify and evaluate the relationship of smectite-illite transformation to undercompaction. Work was performed at the East Flour Bluff oil field, Nueces County, TX and the Ann Mag oil field, south TX.

  13. Multistage treatment wetland for treatment of reject waters from digested sludge dewatering.

    PubMed

    Gajewska, M; Obarska-Pempkowiak, H

    2013-01-01

    The paper presents the influence of sewage composition on treatment in pilot-scale facility for reject waters (RW) from sewage sludge centrifugation. The facility consisted of mechanical (two tanks with 10 d retention each) and biological parts composed of three subsurface flow reed beds working in batch. Two years of monitoring of the facility proved high efficiency removal of predominant pollutants: chemical oxygen demand (COD) 75-80%, biochemical oxygen demand (BOD) 82.2-95.5% and total nitrogen 78.7-93.9% for low ratio of BOD5/COD in discharged RW. The differences in efficiency removal were correlated with the composition of organics and nitrogen compounds rather than with concentrations. It was assumed that high concentration of colloidal fraction of Org-N and COD in discharged RW led to a decrease in efficiency removal. PMID:24056417

  14. A new model of coal-water interaction and relevance for dewatering

    SciTech Connect

    Suuberg, E.M.

    1992-12-18

    This project is concerned with a basic scientific question concerning the properties of coal- to what extent is the ability of coal to hold moisture a manifestation of the well-known ability of coal to swell, when exposed to good solvents The question implies that the long-held belief that coal holds a significant portion of its moisture by classical capillary condensation processes, is possibly in error. This seems to be a very real possibility for low rank coals, i.e. lignites. To explore this hypothesis further requires an examination of the basic phenomena governing the swelling of coals in good solvents. This is the focus of the first part of this project. The possibility that coal holds a significant portion of its moisture by solvent swelling mechanisms leads to an interesting technical issue. It is well known that simple drying of low rank coals is ineffective because the process is reversible, to a significant degree. Pyrolytic treatments of the coals in oil, steam or liquid water itself. Pyrolytically remove oxygen groups, which are assumed to be those that hold water most strongly by hydrogen bonding. The treatments have been designed to minimize tar formation and decrepitation of the particles, both highly undesirable. In relation to the present new hypothesis concerning water retention, it is likely that a sound approach to permanent drying would involve highly crosslinking the coal at mild drying conditions. The crosslinked coal could not swell sufficiently to hold much water. It is identifying processes to achieve this goal, that constitute the objective of the second phase of this work.

  15. Pressate from peat dewatering as a substrate for bacterial growth. [Rhizopus arrhizus; Xanthomonas campestris; Aureobasidium

    SciTech Connect

    Mulligan, C.N.; Cooper, D.G.

    1985-07-01

    This study considered the possibility of using water expressed during the drying of fuel-grade peat as a substrate for microbial growth. Highly humified peat pressed for 2.5 min at 1.96 MPa produced water with a chemical oxygen demand of 690 mg/liter. Several biological compounds could be produced by using the organic matter inexpressed peat water as a substrate. These included polymers such as chitosan, contained in the cell wall of Rhizopus arrhizus, and two extracellular polysaccharides, xanthan gum and pullulan, produced by Bacillus subtilis grown in the expressed water. Small additions of nutrients to the peat pressate were necessary to obtain substantial yields of products. The addition of peptone, yeast extract, and glucose improved production of the various compounds. Biological treatment improved the quality of the expressed water to the extent that in an industrial process it could be returned to the environment.

  16. Digestion and dewatering characteristics of waste activated sludge treated by an anaerobic biofilm system.

    PubMed

    Wang, Tianfeng; Shao, Liming; Li, Tianshui; Lü, Fan; He, Pinjing

    2014-02-01

    Immobilization of microorganisms for sludge anaerobic digestion was investigated in this study. The effects of filler properties on anaerobic digestion and dewaterability of waste activated sludge were assessed at mesophilic temperature in batch mode. The results showed that the duration of the methanogenic stage of reactors without filler, with only filler, and with pre-incubated filler was 39days, 19days and 13days, respectively, during which time the protein was degraded by 45.0%, 29.4% and 30.0%, and the corresponding methane yield was 193.9, 107.2 and 108.2mL/g volatile suspended solids added, respectively. On day 39, the final protein degradation efficiency of the three reactors was 45.0%, 40.9% and 42.0%, respectively. The results of normalized capillary suction time and specific resistance to filtration suggested that the reactor incorporating pre-incubated filler could improve the dewaterability of digested sludge, while the effect of the reactor incorporating only filler on sludge dewaterability was uncertain. PMID:24355503

  17. 40 CFR 450.21 - Effluent limitations reflecting the best practicable technology currently available (BPT).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... limitations reflecting the best practicable technology currently available (BPT). Except as provided in 40 CFR...) Dewatering. Discharges from dewatering activities, including discharges from dewatering of trenches...

  18. 40 CFR 450.21 - Effluent limitations reflecting the best practicable technology currently available (BPT).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... limitations reflecting the best practicable technology currently available (BPT). Except as provided in 40 CFR...) Dewatering. Discharges from dewatering activities, including discharges from dewatering of trenches...

  19. 40 CFR 270.42 - Permit modification at the request of the permittee.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...specified below) 2 f. Tanks used for neutralization, dewatering, phase separation...chemical treatment technologies: neutralization, dewatering, phase separation...chemical treatment technologies: neutralization, dewatering, phase...

  20. 40 CFR 270.42 - Permit modification at the request of the permittee.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...specified below) 2 f. Tanks used for neutralization, dewatering, phase separation...chemical treatment technologies: neutralization, dewatering, phase separation...chemical treatment technologies: neutralization, dewatering, phase...

  1. 40 CFR 270.42 - Permit modification at the request of the permittee.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...specified below) 2 f. Tanks used for neutralization, dewatering, phase separation...chemical treatment technologies: neutralization, dewatering, phase separation...chemical treatment technologies: neutralization, dewatering, phase...

  2. 40 CFR 270.42 - Permit modification at the request of the permittee.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...specified below) 2 f. Tanks used for neutralization, dewatering, phase separation...chemical treatment technologies: neutralization, dewatering, phase separation...chemical treatment technologies: neutralization, dewatering, phase...

  3. 40 CFR 270.42 - Permit modification at the request of the permittee.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...specified below) 2 f. Tanks used for neutralization, dewatering, phase separation...chemical treatment technologies: neutralization, dewatering, phase separation...chemical treatment technologies: neutralization, dewatering, phase...

  4. Pharmaceuticals, hormones, anthropogenic waste indicators, and total estrogenicity in liquid and solid samples from municipal sludge stabilization and dewatering

    USGS Publications Warehouse

    Furlong, Edward T.; Gray, James L.; Quanrud, David M.; Teske, Sondra S.; Werner, Stephen L.; Esposito, Kathleen; Marine, Jeremy; Ela, Wendell P.; Zaugg, Steven D.; Phillips, Patrick; Stinson, Beverley

    2012-01-01

    The ubiquitous presence of pharmaceuticals and other emerging contaminants, or trace organic compounds, in surface water has resulted in research and monitoring efforts to identify contaminant sources to surface waters and to better understand loadings from these sources. Wastewater treatment plant discharges have been identified as an important point source of trace organic compounds to surface water and understanding the transport and transformation of these contaminants through wastewater treatment process is essential to controlling their introduction to receiving waters.

  5. Analytical solution for enhanced recharge around a bedrock exposure caused by deep-aquifer dewatering through a variable thickness aquitard

    NASA Astrophysics Data System (ADS)

    Kompanizare, Mazda; Price, Jonathan S.

    2014-12-01

    In this study an analytical solution was developed to predict steady radially-symmetric percolation rates from an aquifer underlain by a variable thickness aquitard. The solutions consider an aquitard with constant thickness and with radial-symmetrically increasing thickness outward from the center. The solution was used to predict the percolation rate from a peat layer around a bedrock outcrop in the James Bay Lowland near the De Beers Victor diamond mine. In this case the marine sediment layer limited the direct connection between the peat layer and the bedrock as an aquitard. Our zero order solution with constant marine sediment thickness showed the best fit to the steady state water level data of June 2012. It was found that the enhanced recharge around bioherms (i.e., at rates greater than the regional average of 0.7 mm/day) will only occur in marine sediments less than 4.3 m thick, for extreme depressurization of 30 m.

  6. Temperature- and pH-Responsive Benzoboroxole-Based Polymers for Flocculation and Enhanced Dewatering of Fine Particle Suspensions.

    PubMed

    Lu, Han; Wang, Yinan; Li, Lin; Kotsuchibashi, Yohei; Narain, Ravin; Zeng, Hongbo

    2015-12-16

    Random copolymers based on N-isopropylacrylamide (NIPAAm) containing 2-aminoethyl methacrylamide hydrochloride (AEMA) and 5-methacrylamido-1,2-benzoboroxole (MAAmBo) were synthesized and subsequently evaluated for their performance in solid-liquid separation at various pH and temperatures. The strong interactions between benzoboroxole residues and kaolin hydroxyl groups were evaluated for the first time in the flocculation of fine particle suspensions. The lower critical solution temperatures (LCSTs) of PAMN decreases because of the hydrophobic nature of the benzoboroxole moieties, resulting in strong hydrophobic interaction at temperatures higher than the LCSTs. Temperature and pH responsive polymer, P(AEMA51-st-MAAmBo76-st-NIPAM381) (denoted as PAMN) shows the ability to induce fastest settling at a low dosage of 25 ppm and under the condition of pH 9 and 50 °C. The accelerated settling rate is considered to be due to the strong adhesion of benzoboroxole residues to the kaolin hydroxyl groups, the electrical double layer force, and the hydrophobic force. During condensation phase, increasing the pH of sediment to pH 11 could attain the most compact structure. Random copolymers containing benzoboroxole groups act as dispersants (due to pH-responsive character) rather than flocculants at pH 11, providing repulsive force that enables particles to rearrange their position and consolidate well. Through a two-step solid-liquid separation including settling phase and consolidation phase, rapid settling and compact sediment are feasible simultaneously. PMID:26592529

  7. A comparison of instrumental dewatering methods for the separation and concentration of suspended sediment for subsequent trace element analysis

    USGS Publications Warehouse

    Horowitz, A.J.; Elrick, K.A.; Hooper, R.C.

    1989-01-01

    The continuous-flow centrifuges can process whole water at an influent feed rate of 41 per minute; however, when suspended sediment concentrations are low (<30 mg l-1), when small volumes of whole water are to be processed (30 to 401), or when suspended sediment mean grain size is very fine (<10 ??m), influent feed rates of 21 per minute may be more efficient. Tangential-flow filtration can be used to process samples at the rate of 11 per minute. -from Authors

  8. REACTIVATION AND REGROWTH OF INDICATOR ORGANISMS ASSOCIATED WITH ANAEROBICALLY DIGESTED AND DEWATERED BIOSOLIDS: EPA’S PERSPECTIVE

    EPA Science Inventory

    The Water Environment Research Foundation (WERF) recently published a report titled Examination of Reactivation and Regrowth of Fecal Coliforms in Anaerobically Digested Sludges. Seven full-scale publicly owned treatment facilities were sampled several times to determine if bacte...

  9. Vulnerability of larval lamprey to Columbia River hydropower system operations—effects of dewatering on larval lamprey movements and survival

    USGS Publications Warehouse

    Liedtke, Theresa L.; Weiland, Lisa K.; Mesa, Matthew G.

    2015-01-01

    Numbers of adult and juvenile Pacific lamprey ( Entosphenus tridentatus ) in the upper Columbia River Basin of the interior Pacific Northwest have decreased from historical levels (Close and others, 2002), raising concerns f rom State and Federal agencies and Tribal entities. In 1994, the U.S. Fish and Wildlife Service designated Pacific lamprey as a Category 2 candidate species and in 2003, the species was petitioned for listing under the Endangered Species Act. Listing consideration and potential recovery planning are significantly hindered by a lack of information on the basic biology and ecology of lampreys, including limiting factors. To date (2015), several factors that may limit lamprey production require study, including dam passage issues, contaminants, and effects on habitat.

  10. FRUIT CANNERY WASTE ACTIVATED SLUDGE AS A CATTLE FEED INGREDIENT

    EPA Science Inventory

    The feasibility of sludge disposal, from a fruit processing waste activated sludge treatment system, by dewatering and using the dewatered biological sludge solids as cattle feed was evaluated by Snokist Growers at Yakima, Washington. Dewatering of the biological sludge utilizing...

  11. (Created 5/15) UNL Environmental Health and Safety (402) 472-4925 http://ehs.unl.edu

    E-print Network

    Tsymbal, Evgeny Y.

    Operating Procedure (Revised 6/15) DEWATERING.) by regulating certain activities having the potential to discharge pollutants. Dewatering has the potential characteristics. Therefore, dewatering activities are subject to authorization by permit and compliance

  12. 40 CFR 141.76 - Recycle provisions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... recycle spent filter backwash water, thickener supernatant, or liquids from dewatering processes must meet..., thickener supernatant, or liquids from dewatering processes. This notification must include, at a minimum..., thickener supernatant, and liquids from dewatering processes), the hydraulic conveyance used to...

  13. 40 CFR 141.76 - Recycle provisions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... recycle spent filter backwash water, thickener supernatant, or liquids from dewatering processes must meet..., thickener supernatant, or liquids from dewatering processes. This notification must include, at a minimum..., thickener supernatant, and liquids from dewatering processes), the hydraulic conveyance used to...

  14. 40 CFR 141.76 - Recycle provisions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... recycle spent filter backwash water, thickener supernatant, or liquids from dewatering processes must meet..., thickener supernatant, or liquids from dewatering processes. This notification must include, at a minimum..., thickener supernatant, and liquids from dewatering processes), the hydraulic conveyance used to...

  15. 40 CFR 141.76 - Recycle provisions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... recycle spent filter backwash water, thickener supernatant, or liquids from dewatering processes must meet..., thickener supernatant, or liquids from dewatering processes. This notification must include, at a minimum..., thickener supernatant, and liquids from dewatering processes), the hydraulic conveyance used to...

  16. 40 CFR 141.76 - Recycle provisions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... recycle spent filter backwash water, thickener supernatant, or liquids from dewatering processes must meet..., thickener supernatant, or liquids from dewatering processes. This notification must include, at a minimum..., thickener supernatant, and liquids from dewatering processes), the hydraulic conveyance used to...

  17. 40 CFR 435.43 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Drilling Fluids, Drill Cuttings, and Dewatering Effluent: 1 (A) All coastal areas...drilling fluids, drill cuttings, and dewatering effluent SPP Toxicity Minimum 96-hour... Non-aqueous drilling fluids and dewatering effluent No discharge. Drill...

  18. 40 CFR 435.44 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Fluids and Drill Cuttings and Dewatering Effluent: 1 All facilities...fluids, drill cuttings, and dewatering effluent Free Oil No discharge...Non-aqueous drilling fluids and dewatering effluent No discharge....

  19. 40 CFR 141.76 - Recycle provisions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...thickener supernatant, or liquids from dewatering processes must meet the requirements...thickener supernatant, or liquids from dewatering processes. This notification must...thickener supernatant, and liquids from dewatering processes), the hydraulic...

  20. 40 CFR 141.76 - Recycle provisions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...thickener supernatant, or liquids from dewatering processes must meet the requirements...thickener supernatant, or liquids from dewatering processes. This notification must...thickener supernatant, and liquids from dewatering processes), the hydraulic...

  1. 40 CFR 435.44 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...Fluids and Drill Cuttings and Dewatering Effluent: 1 All facilities...fluids, drill cuttings, and dewatering effluent Free Oil No discharge...Non-aqueous drilling fluids and dewatering effluent No discharge....

  2. 40 CFR 141.76 - Recycle provisions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...thickener supernatant, or liquids from dewatering processes must meet the requirements...thickener supernatant, or liquids from dewatering processes. This notification must...thickener supernatant, and liquids from dewatering processes), the hydraulic...

  3. 40 CFR 435.45 - Standards of performance for new sources (NSPS).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Drilling Fluids, Drill Cuttings, and Dewatering Effluent: 1 (A) All coastal areas...drilling fluids, drill cuttings, and dewatering effluent SPP Toxicity Minimum 96-hour... Non-aqueous drilling fluids and dewatering effluent No discharge. Drill...

  4. 40 CFR 435.44 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...Fluids and Drill Cuttings and Dewatering Effluent: 1 All facilities...fluids, drill cuttings, and dewatering effluent Free Oil No discharge...Non-aqueous drilling fluids and dewatering effluent No discharge....

  5. 40 CFR 435.45 - Standards of performance for new sources (NSPS).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...Drilling Fluids, Drill Cuttings, and Dewatering Effluent: 1 (A) All coastal areas...drilling fluids, drill cuttings, and dewatering effluent SPP Toxicity Minimum 96-hour... Non-aqueous drilling fluids and dewatering effluent No discharge. Drill...

  6. 40 CFR 435.43 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...Drilling Fluids, Drill Cuttings, and Dewatering Effluent: 1 (A) All coastal areas...drilling fluids, drill cuttings, and dewatering effluent SPP Toxicity Minimum 96-hour... Non-aqueous drilling fluids and dewatering effluent No discharge. Drill...

  7. 40 CFR 435.44 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Fluids and Drill Cuttings and Dewatering Effluent: 1 All facilities...fluids, drill cuttings, and dewatering effluent Free Oil No discharge...Non-aqueous drilling fluids and dewatering effluent No discharge....

  8. 40 CFR 435.45 - Standards of performance for new sources (NSPS).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...Drilling Fluids, Drill Cuttings, and Dewatering Effluent: 1 (A) All coastal areas...drilling fluids, drill cuttings, and dewatering effluent SPP Toxicity Minimum 96-hour... Non-aqueous drilling fluids and dewatering effluent No discharge. Drill...

  9. 40 CFR 435.44 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...Fluids and Drill Cuttings and Dewatering Effluent: 1 All facilities...fluids, drill cuttings, and dewatering effluent Free Oil No discharge...Non-aqueous drilling fluids and dewatering effluent No discharge....

  10. 40 CFR 435.45 - Standards of performance for new sources (NSPS).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...Drilling Fluids, Drill Cuttings, and Dewatering Effluent: 1 (A) All coastal areas...drilling fluids, drill cuttings, and dewatering effluent SPP Toxicity Minimum 96-hour... Non-aqueous drilling fluids and dewatering effluent No discharge. Drill...

  11. 40 CFR 141.76 - Recycle provisions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...thickener supernatant, or liquids from dewatering processes must meet the requirements...thickener supernatant, or liquids from dewatering processes. This notification must...thickener supernatant, and liquids from dewatering processes), the hydraulic...

  12. 76 FR 60941 - Policy Regarding Submittal of Amendments for Processing of Equivalent Feed at Licensed Uranium...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-30

    ...such as water treatment plants or mine dewatering operations...water treatment facilities and mine dewatering operations, are equivalent to the...treating drinking water sources and mine dewatering) are processing as alternate...

  13. 75 FR 5564 - Notice of a Project Waiver of Section 1605 (Buy American Requirement) of the American Recovery...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-03

    ...a foreign manufactured rotary sludge dewatering press. This is a project specific waiver...determined that a rotary press sludge dewatering unit, manufactured by Fournier Industries...purchase of a 6 channel rotary press sludge dewatering unit, manufactured by Fournier...

  14. 40 CFR 435.45 - Standards of performance for new sources (NSPS).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Drilling Fluids, Drill Cuttings, and Dewatering Effluent: 1 (A) All coastal areas...drilling fluids, drill cuttings, and dewatering effluent SPP Toxicity Minimum 96-hour... Non-aqueous drilling fluids and dewatering effluent No discharge. Drill...

  15. 40 CFR 141.76 - Recycle provisions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...thickener supernatant, or liquids from dewatering processes must meet the requirements...thickener supernatant, or liquids from dewatering processes. This notification must...thickener supernatant, and liquids from dewatering processes), the hydraulic...

  16. 40 CFR 435.43 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...Drilling Fluids, Drill Cuttings, and Dewatering Effluent: 1 (A) All coastal areas...drilling fluids, drill cuttings, and dewatering effluent SPP Toxicity Minimum 96-hour... Non-aqueous drilling fluids and dewatering effluent No discharge. Drill...

  17. Visualizing "Fuzzy" Construction Materials Using VITASCOPE's ParticleWorks Add-On Vineet R. Kamat, S.M.ASCE*

    E-print Network

    Kamat, Vineet R.

    that involve such fuzzy materials include placing concrete, dumping dirt, shotcreting, sandblasting, dewatering, dumping dirt, shotcreting, sandblasting, dewatering, water distribution, and inserting slurry. We

  18. NORTH-SOUTH VARIABILITY IN THE HISTORY OF DEFORMATION AND FLUID VENTING ACROSS HYDRATE RIDGE, CASCADIA MARGIN

    E-print Network

    Goldfinger, Chris

    of sediment compaction, dewatering, and deformation than the younger slope basin strata preserved at SHR prompted investigations of seafloor fluid flow and the dewatering processes associated with accretionary

  19. Process simulator-based optimization of biorefinery downstream processes under the Generalized Disjunctive Programming framework

    E-print Network

    Grossmann, Ignacio E.

    are proposed spanning from the economic optimization of two different17 distillation columns, the dewatering Keywords: Optimization, Generalized Disjunctive Programming, MINLP, Downstream,22 Dewatering, Distillation

  20. Modeling Hydrodynamics and Bed-Load Transport of Coarse Sediments in the Great Bay Estuary, NH, Using a 2-D Kinematic Flooding-Dewatering Model

    E-print Network

    of 0.18. The typical tidal range is on the order of 2.5 m at the Gulf of Maine mouth and decreases to about 1.8 m in inner estuarine locations. The Gulf of Maine connects to the inner estuary by way complex system with low freshwater input, having main channel tidal currents ranging between 0.5 and 2 m

  1. Reduction in energy usage during dry grind ethanol production by enhanced enzymatic dewatering of whole stillage: plant trial, process model and economic analysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A plant trial was conducted at a 54 MGPY dry grind fuel ethanol facility to evaluate the use of enhanced water removal from whole stillage by enzyme addition during fermentation. Laboratory data had previously shown significant improvements in water removal that could potentially result in significa...

  2. Waste treatment process for removal of contaminants from aqueous, mixed-waste solutions using sequential chemical treatment and crossflow microfiltration, followed by dewatering

    DOEpatents

    Vijayan, S.; Wong, C.F.; Buckley, L.P.

    1994-11-22

    In processes of this invention aqueous waste solutions containing a variety of mixed waste contaminants are treated to remove the contaminants by a sequential addition of chemicals and adsorption/ion exchange powdered materials to remove the contaminants including lead, cadmium, uranium, cesium-137, strontium-85/90, trichloroethylene and benzene, and impurities including iron and calcium. Staged conditioning of the waste solution produces a polydisperse system of size enlarged complexes of the contaminants in three distinct configurations: water-soluble metal complexes, insoluble metal precipitation complexes, and contaminant-bearing particles of ion exchange and adsorbent materials. The volume of the waste is reduced by separation of the polydisperse system by cross-flow microfiltration, followed by low-temperature evaporation and/or filter pressing. The water produced as filtrate is discharged if it meets a specified target water quality, or else the filtrate is recycled until the target is achieved. 1 fig.

  3. Waste treatment process for removal of contaminants from aqueous, mixed-waste solutions using sequential chemical treatment and crossflow microfiltration, followed by dewatering

    DOEpatents

    Vijayan, Sivaraman (Deep River, CA); Wong, Chi F. (Pembroke, CA); Buckley, Leo P. (Deep River, CA)

    1994-01-01

    In processes of this invention aqueous waste solutions containing a variety of mixed waste contaminants are treated to remove the contaminants by a sequential addition of chemicals and adsorption/ion exchange powdered materials to remove the contaminants including lead, cadmium, uranium, cesium-137, strontium-85/90, trichloroethylene and benzene, and impurities including iron and calcium. Staged conditioning of the waste solution produces a polydisperse system of size enlarged complexes of the contaminants in three distinct configurations: water-soluble metal complexes, insoluble metal precipitation complexes, and contaminant-bearing particles of ion exchange and adsorbent materials. The volume of the waste is reduced by separation of the polydisperse system by cross-flow microfiltration, followed by low-temperature evaporation and/or filter pressing. The water produced as filtrate is discharged if it meets a specified target water quality, or else the filtrate is recycled until the target is achieved.

  4. Use of a single-bowl continuous-flow centrifuge for dewatering suspended sediments: effect on sediment physical and chemical characteristics

    USGS Publications Warehouse

    Rees, T.F.; Leenheer, J.A.; Ranville, J.F.

    1991-01-01

    Sediment-recovery efficiency of 86-91% is comparable to that of other types of CFC units. The recovery efficiency is limited by the particle-size distribution of the feed water and by the limiting particle diameter that is retained in the centrifuge bowl. Contamination by trace metals and organics is minimized by coating all surfaces that come in contact with the sample with either FEP or PFA Teflon and using a removable FEP Teflon liner in the centrifuge bowl. -from Authors

  5. Enhancement of activated sludge dewatering performance by combined composite enzymatic lysis and chemical re-flocculation with inorganic coagulants: Kinetics of enzymatic reaction and re-flocculation morphology.

    PubMed

    Chen, Zhan; Zhang, Weijun; Wang, Dongsheng; Ma, Teng; Bai, Runying

    2015-10-15

    The feasibility of combined process of composite enzymatic treatment and chemical flocculation with inorganic salt coagulants was investigated in this study. The evolution of extracellular polymeric substances (EPS) distribution, composition and morphological properties were analyzed to unravel the sludge conditioning mechanism. It was found that sludge filtration performance was deteriorated due to release of a large amount of biopolymers after enzymatic treatment. The change in EPS followed the pseudo-first-order kinetic equation well under enzymatic treatment. The feeding modes of enzymes had a significant influence on sludge lysis efficiency under compound enzymes treatment. Alpha amylase + protease was more effective in solubilization than other two addition modes (protease + ?-amylase or simultaneous addition). The sludge floc re-formed and macromolecule biopolymers were effectively removed through coagulation process. At the same time, both of filtration rate and cake solid content of sludge treated with enzymes were improved with increasing dosage of coagulants, and ferric iron (FeCl3) had better performance in sludge dewaterability enhancement than polyaluminium chloride (PACl). In addition, sludge filtration property was slightly deteriorated, while the cake moisture reduction was favored at the optimal dosage of inorganic coagulants. PMID:26196306

  6. A new model of coal-water interaction and relevance for dewatering. Quarterly technical progress report, December 1, 1991--February 28, 1992

    SciTech Connect

    Suuberg, E.M.

    1992-09-01

    The possibility that coal holds a significant portion of its moisture by solvent swelling mechanisms leads to an interesting technical issue. It is well known that simple drying of low rank coals at minemouth is ineffective because the process is reversible, to a significant degree. The economic advantages of pre-shipment drying have however dictated a search for ``permanent`` drying procedures. These have been developed by largely empirical means, and involve mild pyrolytic treatments of the coals in oil, steam or liquid water itself. The idea has always been to pyrolytically remove oxygen groups, which are assumed to be those that hold water most strongly by hydrogen bonding. The treatments have been designed to minimize tar formation and decrepitation of the particles, both highly undesirable. In relation to the present new hypothesis concerning water retention, it is likely that a sound approach to permanent drying would involve highly crosslinking the coal at mild drying conditions. The crosslinked coal could not swell sufficiently to hold much water. It is identifying processes to achieve this goal, that constitute the objective of the second phase of this work.

  7. A new model of coal-water interaction and relevance for dewatering. Quarterly technical progress report, 1 September 1991--30 November 1991

    SciTech Connect

    Suuberg, E.M.

    1991-12-31

    This project is concerned with the ability of coal to hold moisture is it a manifestation of the well-known ability of coal to swell, when exposed to good solvents? The question implies that the long-held belief that coal holds a significant portion of its moisture by classical capillary condensation processes, is possibly in error. To explore this hypothesis further requires an examination of the basic phenomena governing the swelling of coals in good solvents. This is the focus of the first part of this project. The possibility that coal holds a significant portion of its moisture by solvent swelling mechanisms leads to an interesting technical issue. It is well known that simple drying of low rank coals is ineffective because the process is reversible. Mild pyrolytic treatments of the coals in oil, steam or liquid water itself pyrolytically remove oxygen groups, which are assumed to be those that hold water most strongly by hydrogen bonding. The treatments have been designed to minimize tar formation and decrepitation of the particles. In relation to the present new hypothesis concerning water retention, it is likely that a sound approach to permanent drying would involve highly crosslinking the coal at mild drying conditions. The crosslinked coal could not swell sufficiently to hold much water. It is identifying processes to achieve this goal, that constitute the objective of the second phase of this work.

  8. A new model of coal-water interaction and relevance for dewatering. Quarterly technical progress report, 1 June--31 August, 1992

    SciTech Connect

    Suuberg, E.M.; Yun, Y.; Lilly, W.D.; Leung, K.; Gates, T.

    1992-12-31

    This project is concerned with a basic scientific question concerning the properties of coal -- to what extent is the ability of coal to hold moisture a manifestation of the well-known ability of coal to swell, when exposed to good solvents? The question implies that the long-held belief that coal holds a significant portion of its moisture by classical capillary condensation processes, is possibly in error. This seems to be a very real possibility for low rank coals- i.e. lignites. To explore this hypothesis further requires an examination of the basic phenomena governing the swelling of coals in good solvents. This is the focus of the first part of this project. The possibility that coal holds a significant portion of its moisture by solvent swelling mechanisms leads to an interesting technical issue. It is well known that simple drying of low rank coals at minemouth is ineffective because the process is reversible, to a significant degree. The economic advantages of preshipment drying have however dictated a search for ``permanent`` drying procedures. These have been developed by largely empirical means, and involve mild pyrolytic treatments of the coals in oil, steam or liquid water itself The idea has always been to pyrolytically remove oxygen groups, which are assumed to be those that hold water most strongly by hydrogen bonding. The treatments have been designed to minimize tar formation and decrepitation of the particles, both highly undesirable. In relation to the present new hypothesis concerning water retention, it is likely that a sound approach to permanent drying would involve highly crosslinking the coal at mild drying conditions. The crosslinked coal could not swell sufficiently to hold much water. It is identifying processes to achieve this goal, that constitute the objective of the second phase of this work.

  9. A new model of coal-water interaction and relevance for dewatering. Quarterly technical progress report, 1 March--31 May 1992

    SciTech Connect

    Suuberg, E.M.

    1992-12-18

    This project is concerned with a basic scientific question concerning the properties of coal- to what extent is the ability of coal to hold moisture a manifestation of the well-known ability of coal to swell, when exposed to good solvents? The question implies that the long-held belief that coal holds a significant portion of its moisture by classical capillary condensation processes, is possibly in error. This seems to be a very real possibility for low rank coals, i.e. lignites. To explore this hypothesis further requires an examination of the basic phenomena governing the swelling of coals in good solvents. This is the focus of the first part of this project. The possibility that coal holds a significant portion of its moisture by solvent swelling mechanisms leads to an interesting technical issue. It is well known that simple drying of low rank coals is ineffective because the process is reversible, to a significant degree. Pyrolytic treatments of the coals in oil, steam or liquid water itself. Pyrolytically remove oxygen groups, which are assumed to be those that hold water most strongly by hydrogen bonding. The treatments have been designed to minimize tar formation and decrepitation of the particles, both highly undesirable. In relation to the present new hypothesis concerning water retention, it is likely that a sound approach to permanent drying would involve highly crosslinking the coal at mild drying conditions. The crosslinked coal could not swell sufficiently to hold much water. It is identifying processes to achieve this goal, that constitute the objective of the second phase of this work.

  10. Comparison of computation methods for CBM production performance 

    E-print Network

    Mora, Carlos A.

    2009-06-02

    methane production is somewhat complicated and has led to numerous methods of approximating production performance. Many CBM reservoirs go through a dewatering period before significant gas production occurs. With dewatering, desorption of gas...

  11. The big crunch: Physical and chemical expressions of arc/continent collision in the Western Bismarck arc

    E-print Network

    Sandiford, Mike

    occurring suggests that either slab dewatering is not essential for initiating volcanism or that the process of dewatering continues long after subduction has ceased. Limited data from similar collision zones elsewhere

  12. Regional P wave velocity structure of the Northern Cascadia Subduction Zone

    E-print Network

    Ramachandran, Kumar

    of the upper fore-arc mantle and provide evidence for slab dewatering and densification. Tertiary sedimentary region of slab dewatering and densification and may therefore partly result from a higher rate of slab

  13. propagate away from the wells and disturbs a larger and larger volume, the probability increases

    E-print Network

    Benton, Michael

    be linked to disposal of fluids gen- erated during Oklahoma dewatering and after hydraulic fracturing, and Missis- sippi Lime dewatering plays. The injection-linked seismicity near Jones occurs up to 35 km away

  14. Transactions of the American Fisheries Society 128:222240, 1999 Copyright by the American Fisheries Society 1999

    E-print Network

    Jager, Henriette I.

    of seasonal shifts in flow on simulated dewatering of redds was equally important and tended to compensate (dewatering, scouring, and temperature-related mortality) also lead to nonadditive effects of the two climatic

  15. Capillary Suction Time (CST) Test: Developments in testing methodology and reliability of results 

    E-print Network

    Sawalha, Ola

    2011-01-01

    The dewatering of wastewater sludge (slurry) is a routine operation at wastewater treatment plants, and the results of dewaterability tests underpin the selection of dewatering processes. The two most commonly applied ...

  16. 40 CFR 721.8965 - 1H-Pyrole-2, 5-dione, 1-(2,4,6-tribromophenyl)-.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... dewatering step during polymerization of acrylonitrile/butadiene/styrene), and (g)(5). (iii) Industrial... apply to releases of the PMN substance during the dewatering step of the polymerization reactions...

  17. Modeling tidal flow in the Great Bay Estuary, New Hampshire, using a depth averaged

    E-print Network

    Modeling tidal flow in the Great Bay Estuary, New Hampshire, using a depth averaged flooding-dewatering. The hydrodynamic model uses a fixed boundary computation domain and accounts for flooding-dewatering over tidal

  18. Dr. H.M. Watt Project QA Officer

    E-print Network

    District of Columbia, University of the

    and the associated trenching diverts and ponds ground water. Second is the dewatering during construction or treatment. Also, dewatering has been poorly monitored in the district. Land use is extremely critical

  19. 40 CFR 721.8965 - 1H-Pyrole-2, 5-dione, 1-(2,4,6-tribromophenyl)-.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... dewatering step during polymerization of acrylonitrile/butadiene/styrene), and (g)(5). (iii) Industrial... apply to releases of the PMN substance during the dewatering step of the polymerization reactions...

  20. Engineer Manual 1110-2-5026

    E-print Network

    US Army Corps of Engineers

    -1 Dewatering . . . . . . . . . . . . . . . . . . 3-2 3-1 Transport, Handling, and Storage . . . . . . . 3-3 3-1 Cost Analysis for Dewatering and Transport . . . . . . . . . . . . . 3-4 3-7 CHAPTER 4 HABITAT

  1. 40 CFR 721.8965 - 1H-Pyrole-2, 5-dione, 1-(2,4,6-tribromophenyl)-.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... dewatering step during polymerization of acrylonitrile/butadiene/styrene), and (g)(5). (iii) Industrial... apply to releases of the PMN substance during the dewatering step of the polymerization reactions...

  2. Groundwater flow to a horizontal or slanted well in an unconfined aquifer

    E-print Network

    Zhan, Hongbin

    are useful for the parameter identification, design of remediation systems, drainage, and mine dewatering, and mine dewatering [Hantush and Papadopulos, 1962]. [4] An early study of fluid flow to a horizontal well

  3. 40 CFR 721.8965 - 1H-Pyrole-2, 5-dione, 1-(2,4,6-tribromophenyl)-.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... dewatering step during polymerization of acrylonitrile/butadiene/styrene), and (g)(5). (iii) Industrial... apply to releases of the PMN substance during the dewatering step of the polymerization reactions...

  4. Chi-man Leung Jiu J. Jiao

    E-print Network

    Jiao, Jiu Jimmy

    be weakened. Besides, excess Ca2+ may deposit in the dewatering systems in the area, which may affect Department. Discussion of the behavior of Ca2+ is instructional to foundation and slope dewatering designs

  5. 40 CFR 721.8965 - 1H-Pyrole-2, 5-dione, 1-(2,4,6-tribromophenyl)-.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... dewatering step during polymerization of acrylonitrile/butadiene/styrene), and (g)(5). (iii) Industrial... apply to releases of the PMN substance during the dewatering step of the polymerization reactions...

  6. Bogen, N. L.; Girty, G. H.; Hanson, R. E.; Merguerian, Charles; and Schweickert, R. A., 1980, Contrasting styles of deformation during the Nevadan Orogeny, Sierra Nevada,

    E-print Network

    Merguerian, Charles

    that strain hardening and dewatering had already occurred in the pre-Nevadan terranes, while Jurassic rocks may have undergone compaction and dewatering during the orogeny. To Cite This Abstract: Bogen, N. L

  7. 75 FR 78985 - County of DuPage; Notice of Preliminary Permit Application Accepted for Filing and Soliciting...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-17

    ... slide gates for isolating and dewatering the penstock; (3) an 870-foot-long, 28- foot-diameter penstock... one or two slide gates for isolating and dewatering the tailrace tunnel; (8) a substation...

  8. 2005 Geological Society of America. For permission to copy, contact Copyright Permissions, GSA, or editing@geosociety.org. Geology; August 2005; v. 33; no. 8; p. 625628; doi: 10.1130/G21270.1; 4 figures; 1 table. 625

    E-print Network

    Montgomery, David R.

    ; 1 table. 625 Formation of Martian outflow channels by catastrophic dewatering of evaporite deposits channels through catastrophic dewatering of evaporite deposits. MOLA transects across Valles Marineris show adequate to dehydrate hydrous evaporites would trigger significant volumetric expansion

  9. 40 CFR 421.156 - Pretreatment standards for new sources.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...000 Fluoride 0.000 0.000 (k) Beryl Ore Gangue Dewatering. PSNS for the Primary Beryllium Subcategory Pollutant...Fluoride 36.505 20.756 (l) Bertrandite Ore Gangue Dewatering. PSNS for the Primary Beryllium Subcategory...

  10. 40 CFR 421.153 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...000 Fluoride 0.000 0.000 (k) Beryl Ore Gangue Dewatering. BAT Limitations for the Primary Beryllium Subcategory...Fluoride 36.505 20.756 (l) Bertrandite Ore Gangue Dewatering. BAT Limitations for the Primary Beryllium...

  11. 40 CFR 98.468 - Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...includes the semi-solid materials remaining after these materials are dewatered via a belt process, centrifuge, or similar dewatering process. Solid waste has the meaning established by the Administrator pursuant to the Solid Waste Disposal Act (42...

  12. 40 CFR 421.153 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...000 Fluoride 0.000 0.000 (k) Beryl Ore Gangue Dewatering. BAT Limitations for the Primary Beryllium Subcategory...Fluoride 36.505 20.756 (l) Bertrandite Ore Gangue Dewatering. BAT Limitations for the Primary Beryllium...

  13. 40 CFR 721.8965 - 1H-Pyrole-2, 5-dione, 1-(2,4,6-tribromophenyl)-.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...ii), (g)(4)(i), (g)(4)(iii) (except the dewatering step during polymerization of acrylonitrile/butadiene...does not apply to releases of the PMN substance during the dewatering step of the polymerization reactions from use. (b)...

  14. 40 CFR 421.156 - Pretreatment standards for new sources.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...000 Fluoride 0.000 0.000 (k) Beryl Ore Gangue Dewatering. PSNS for the Primary Beryllium Subcategory Pollutant...Fluoride 36.505 20.756 (l) Bertrandite Ore Gangue Dewatering. PSNS for the Primary Beryllium Subcategory...

  15. 40 CFR 421.156 - Pretreatment standards for new sources.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...000 Fluoride 0.000 0.000 (k) Beryl Ore Gangue Dewatering. PSNS for the Primary Beryllium Subcategory Pollutant...Flouride 36.505 20.756 (l) Bertrandite Ore Gangue Dewatering. PSNS for the Primary Beryllium Subcategory...

  16. 77 FR 75644 - Malheur National Wildlife Refuge, Harney County, OR; Final Comprehensive Conservation Plan and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-21

    ...Double-O Units would be managed using rotational flooding and dewatering, to enhance productivity for waterfowl and to control carp...highly prescriptive grazing, mowing, farming, and extended dewatering, to reclaim acres overrun with invasive common cattail...

  17. 78 FR 4165 - Notice of Availability of the Draft Environmental Impact Statement for the Arturo Mine Project...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-18

    ...surface disturbance on public lands administered by the BLM. While dewatering is not proposed for this project, pit lakes would form as a result of cessation of dewatering at Goldstrike Mine, located approximately 8 miles to the...

  18. 40 CFR 421.153 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...000 Fluoride 0.000 0.000 (k) Beryl Ore Gangue Dewatering. BAT Limitations for the Primary Beryllium Subcategory...Fluoride 36.505 20.756 (l) Bertrandite Ore Gangue Dewatering. BAT Limitations for the Primary Beryllium...

  19. 40 CFR 721.8965 - 1H-Pyrole-2, 5-dione, 1-(2,4,6-tribromophenyl)-.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...ii), (g)(4)(i), (g)(4)(iii) (except the dewatering step during polymerization of acrylonitrile/butadiene...does not apply to releases of the PMN substance during the dewatering step of the polymerization reactions from use. (b)...

  20. 40 CFR 435.41 - Specialized definitions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...to this subpart that is engaged in the drilling of productive wells. (j) Dewatering effluent means wastewater from drilling fluids and drill cuttings dewatering activities (including but not limited to reserve pits or other tanks or...

  1. 77 FR 13139 - Malheur National Wildlife Refuge, Harney County, OR; Draft Comprehensive Conservation Plan and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-05

    ...Double-O Units would be managed using rotational flooding and dewatering to enhance productivity for waterfowl and to control carp...highly prescriptive grazing, mowing, farming, and extended dewatering to reclaim acres lost to invasive plants, such as...

  2. 40 CFR 721.8965 - 1H-Pyrole-2, 5-dione, 1-(2,4,6-tribromophenyl)-.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...ii), (g)(4)(i), (g)(4)(iii) (except the dewatering step during polymerization of acrylonitrile/butadiene...does not apply to releases of the PMN substance during the dewatering step of the polymerization reactions from use. (b)...

  3. 40 CFR 721.8965 - 1H-Pyrole-2, 5-dione, 1-(2,4,6-tribromophenyl)-.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...ii), (g)(4)(i), (g)(4)(iii) (except the dewatering step during polymerization of acrylonitrile/butadiene...does not apply to releases of the PMN substance during the dewatering step of the polymerization reactions from use. (b)...

  4. 40 CFR 721.8965 - 1H-Pyrole-2, 5-dione, 1-(2,4,6-tribromophenyl)-.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...ii), (g)(4)(i), (g)(4)(iii) (except the dewatering step during polymerization of acrylonitrile/butadiene...does not apply to releases of the PMN substance during the dewatering step of the polymerization reactions from use. (b)...

  5. 40 CFR 421.156 - Pretreatment standards for new sources.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...000 Fluoride 0.000 0.000 (k) Beryl Ore Gangue Dewatering. PSNS for the Primary Beryllium Subcategory Pollutant...Fluoride 36.505 20.756 (l) Bertrandite Ore Gangue Dewatering. PSNS for the Primary Beryllium Subcategory...

  6. 40 CFR 421.153 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...000 Fluoride 0.000 0.000 (k) Beryl Ore Gangue Dewatering. BAT Limitations for the Primary Beryllium Subcategory...Fluoride 36.505 20.756 (l) Bertrandite Ore Gangue Dewatering. BAT Limitations for the Primary Beryllium...

  7. ADAPTIVE CALIBRATION AND CONTROL OF CASCADE PROCESSES WITH UNKNOWN MEASUREMENT MODEL AND ACTUATOR DYNAMICS AND ITS

    E-print Network

    Li, Perry Y.

    is applied to a vacuum dewatering process in paper manufacturing industry. Simulation results show. The vacuum dewatering section in paper manufacturing pro- cess is the motivating example for this class of systems, where moist paper is successively dewatered by multiple vacuum de- watering boxes whose pressure

  8. eScholarship provides open access, scholarly publishing services to the University of California and delivers a dynamic

    E-print Network

    Title: Emplacement and dewatering of the world's largest exposed sand injectite complex Author: Sherry 1 17 August 2012 Q08008, doi:10.1029/2012GC004157 ISSN: 1525-2027 Emplacement and dewatering, multiple pore fluids, and dewatering after emplacement. The injection was initially mobilized from a source

  9. JOIDESJournal Joint Oceanographic Institutions for Deep Earth Sampling

    E-print Network

    the underthrust section near the trench axis. The thinning was interpreted as sediment dewatering due to the load of the overlying plate. These observations suggest that either dewatering is highly dispersed through the lower part of the slope, or dewatering is not accompanied by chemosynthetic vent communities that have been

  10. (Created 4/07; Revised 9/07, 6/08, 10/08, 7/09, 7/10, 7/11, 7/12) UNL Environmental Health and Safety (402) 472-4925 http://ehs.unl.edu

    E-print Network

    Tsymbal, Evgeny Y.

    to those cited above. Site disturbing activities and dewatering are both subject to regulatory requirements)." · Some dewatering of excavations or other structures may require application for and compliance with the "General NPDES Permit Authorizing Dewatering Discharges (General NPDES Permit Number NEG671000)." #12

  11. PLEASE SCROLL DOWN FOR ARTICLE This article was downloaded by: [University of Minnesota

    E-print Network

    Li, Perry Y.

    ://www.informaworld.com/smpp/title~content=t713597247 Method to Characterize the Air Flow and Water Removal Characteristics During Vacuum Dewatering and Water Removal Characteristics During Vacuum Dewatering. Part II--Analysis and Characterization;Method to Characterize the Air Flow and Water Removal Characteristics During Vacuum Dewatering. Part II

  12. 40 CFR 450.21 - Effluent limitations reflecting the best practicable technology currently available (BPT).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... limitations reflecting the best practicable technology currently available (BPT). Except as provided in 40 CFR... intended function of a specific area of the site necessitates that it remain disturbed. (c) Dewatering. Discharges from dewatering activities, including discharges from dewatering of trenches and excavations,...

  13. 75 FR 6389 - Notice of a Regional Project Waiver of Section 1605 (Buy American) of the American Recovery and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-09

    ... Gloucester, Massachusetts (``City'') for the purchase of foreign manufactured rotary sludge dewatering... that two 6-channel rotary press sludge dewatering units, manufactured by Fournier Industries of Quebec... rotary press sludge dewatering units, manufactured by Fournier Industries, by the City, as specified...

  14. Curriculum Vitae Page 1 of 5 Curriculum Vitae

    E-print Network

    /2008 ­ 04/2010 Hydrogeological consultant, Numerical modeling and design of dewatering schemes. Amphos21 Consulting SL, Barcelona, Spain 12/2007 ­ 03/2008 Field hydrogeologist, Monitoring of dewatering consultant, Environmental studies of VOC contaminated sites; design of dewatering schemes; groundwater

  15. HAR Microfluidic Device to Concentrate Microalgae , Q. Nguyen1

    E-print Network

    in the traditional processing comes from concentrating (dewatering) the algae from the dilute growing concentrations (~0.1 wt%). A continuous flow microfluidic dewatering chip has been designed using an innovative concentrating (dewatering) the algae from the dilute concentrations (~0.1 wt%) at which they grow [2

  16. 40 CFR 435.45 - Standards of performance for new sources (NSPS).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... average shall not exceed 29 mg/l. Drilling Fluids, Drill Cuttings, and Dewatering Effluent: 1 (A) All..., and dewatering effluent SPP Toxicity Minimum 96-hour LC50. of the SPP Toxicity Test 4 shall be 3% by... dewatering effluent No discharge. Drill cuttings associated with non-aqueous drilling fluids No discharge....

  17. 40 CFR 450.21 - Effluent limitations reflecting the best practicable technology currently available (BPT).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... the best practicable technology currently available (BPT). Except as provided in 40 CFR 125.30 through... employed as specified by the permitting authority. (c) Dewatering. Discharges from dewatering activities, including discharges from dewatering of trenches and excavations, are prohibited unless managed...

  18. DECISION DOCUMENT NATIONWIDE PERMIT 33

    E-print Network

    US Army Corps of Engineers

    of the Nationwide Permit Temporary Construction, Access, and Dewatering. Temporary structures, work, and discharges, including cofferdams, necessary for construction activities or access fills or dewatering ofconstruction the use of cofferdams to dewater wetlands or other aquatic areas to change their use. Structures left

  19. 40 CFR 450.21 - Effluent limitations reflecting the best practicable technology currently available (BPT).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... the best practicable technology currently available (BPT). Except as provided in 40 CFR 125.30 through... employed as specified by the permitting authority. (c) Dewatering. Discharges from dewatering activities, including discharges from dewatering of trenches and excavations, are prohibited unless managed...

  20. Proceedings of IMECE 2001 2001 ASME International Mechanical Engineering Congress & Exposition

    E-print Network

    Li, Perry Y.

    % of the water from pulp is sequentially removed through gravity, vacuum dewatering, pressing, and thermal drying- rogate measurements, and the pressure settings in the multiple vacuum dewatering boxes are adjusted- ity, vacuum dewatering, mechanical press, and thermal drying in a paper machine, to form end product

  1. 40 CFR 435.45 - Standards of performance for new sources (NSPS).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... average shall not exceed 29 mg/l. Drilling Fluids, Drill Cuttings, and Dewatering Effluent: 1 (A) All..., and dewatering effluent SPP Toxicity Minimum 96-hour LC50. of the SPP Toxicity Test 4 shall be 3% by... dewatering effluent No discharge. Drill cuttings associated with non-aqueous drilling fluids No discharge....

  2. PLEASE SCROLL DOWN FOR ARTICLE This article was downloaded by: [University of Minnesota

    E-print Network

    Li, Perry Y.

    ://www.informaworld.com/smpp/title~content=t713597247 Method to Characterize the Air Flow and Water Removal Characteristics during Vacuum Dewatering and Water Removal Characteristics during Vacuum Dewatering. Part I--Experimental Method',Drying Technology;Method to Characterize the Air Flow and Water Removal Characteristics during Vacuum Dewatering. Part I

  3. INTRODUCTION Studies of fluid flow in convergent margins

    E-print Network

    Fisher, Andrew

    the system (Fryer, 1996). These zones show much greater dewatering of subducted sedi- ments, because of expelled pore fluids to seawater chemistry, and the effects of such shallow dewatering on the composition the décollement and the in- creasingly dewatered underthrust sequence below. Site 1040 also bottomed in a gabbro

  4. 75 FR 5564 - Notice of a Project Waiver of Section 1605 (Buy American Requirement) of the American Recovery...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-03

    ... purchase of a foreign manufactured rotary sludge dewatering press. This is a project specific waiver and... the District and its consultants, it was determined that a rotary press sludge dewatering unit... dewatering unit, manufactured by Fournier Industries, by the District, as specified in its October 7,...

  5. 40 CFR 435.45 - Standards of performance for new sources (NSPS).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... average shall not exceed 29 mg/l. Drilling Fluids, Drill Cuttings, and Dewatering Effluent: 1 (A) All..., and dewatering effluent SPP Toxicity Minimum 96-hour LC50. of the SPP Toxicity Test 4 shall be 3% by... dewatering effluent No discharge. Drill cuttings associated with non-aqueous drilling fluids No discharge....

  6. Department of Civil & Environmental Engineering Geotechnical Group Seminar Series

    E-print Network

    Kamat, Vineet R.

    of Michigan, Ann Arbor Dewatering Wells in a Flowing Artesian Aquifer at Ann Arbor WWTP By Katherine M. Lamb on this seminar series: http://www.umich.edu/~geotech/lecture.html Dewatering, Bypass Pumping, & Power Generation Abstract: Large diameter drilled wells are used all over the world for temporary dewatering activities

  7. India: Gujarat

    Atmospheric Science Data Center

    2013-04-16

    article title:  Dewatering Effects from the Gujarat Earthquake   ... fountaining from the Earth. These effects, referred to as dewatering, can result from intense ground shaking by strong earthquakes in ... with shallow water tables. Scientists initially observed dewatering in parts of the Rann of Kutch (a large salt pan in northern ...

  8. Intern experience with William F. Guyton & Associates: an internship report 

    E-print Network

    Stevens, William Scott, 1953-

    2013-03-13

    Quality and Groundwater Hydrology Study ............ . Effects of Leach Mine Due To Pumping Three Dewatering Mines .............. Elliptical Cone of Depression Showing Anisotropy .............. Time-Drawdown Curve for the Nonequilibrium Equation... mining, and was planning a pilot leach mine. The deep shaft mining involved dewatering a massive confined aquifer in the region. The pilot leach mine, chemical mining of uranium, was located within five miles of the dewatering wells for the deep shaft...

  9. Risk assessment and evaluation of the conductor setting depth in shallow water, Gulf of Mexico 

    E-print Network

    Tu, Yong B.

    2006-08-16

    . Overall, the magnitude for abnormally pressured formations can be contributed to the imbalance between the rates of subsidence and dewatering efficiency of the formation. This can be considered the most frequent cause of abnormally pressured formation... porosity of under-compacted zones and its association with a steep abnormal gradient. This factor can enhance the dewatering and transformation of montmorillonite. However, abnormal pressure retards dewatering and increases salinity, tending to alter...

  10. The Optimization of Well Spacing in a Coalbed Methane Reservoir 

    E-print Network

    Sinurat, Pahala Dominicus

    2012-02-14

    of a coalbed methane reservoir is presented in Fig. 1.5. As shown in Fig. 1.5., the first stage of production profile is the dewatering process. The dewatering process is a mandatory procedure in a coalbed methane reservoir with higher reservoir... starts to desorb. Fig. 1.5 ? Typical coalbed methane production behavior As shown in Fig. 1.5., the first stage of production profile is the dewatering process. The dewatering process is a mandatory procedure in a coalbed methane reservoir...

  11. 40 CFR 240.201-2 - Recommended procedures: Design.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... WASTES GUIDELINES FOR THE THERMAL PROCESSING OF SOLID WASTES Requirements and Recommended Procedures... carcasses, automobile bodies, dewatered sludges from water treatment plants, and industrial process wastes....

  12. 40 CFR 240.200-2 - Recommended procedures: Design.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... WASTES GUIDELINES FOR THE THERMAL PROCESSING OF SOLID WASTES Requirements and Recommended Procedures... stumps, large timbers, furniture, and major appliances), digested and dewatered sludges from waste...

  13. 24. Pump Room interiordewatering pump motor on upper level. Note ...

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

    24. Pump Room interior-dewatering pump motor on upper level. Note the removable roof hatch (steel frame) directly above motor. Dewatering pumps motor control center at left - Hunters Point Naval Shipyard, Drydock No. 4, East terminus of Palou Avenue, San Francisco, San Francisco County, CA

  14. 40 CFR 435.44 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... in 40 CFR 125.30-125.32, any existing point source subject to this subpart must achieve the following... Cuttings and Dewatering Effluent: 1 All facilities except Cook Inlet No discharge. Cook Inlet: Water-based drilling fluids, drill cuttings, and dewatering effluent Free Oil No discharge. 2 Non-aqueous...

  15. 40 CFR 435.43 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... provided in 40 CFR 125.30-125.32, any existing point source subject to this subpart must achieve the... average shall not exceed 29 mg/l. Drilling Fluids, Drill Cuttings, and Dewatering Effluent: 1 (A) All..., and dewatering effluent SPP Toxicity Minimum 96-hour LC50. of the SPP Toxicity Test 4 shall be 3%...

  16. 76 FR 60941 - Policy Regarding Submittal of Amendments for Processing of Equivalent Feed at Licensed Uranium...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-30

    ... treated as alternate feed at conventional mills (57 FR 20532). These license amendments were required... mine dewatering operations. Background As stated above, the NRC is issuing this RIS to clarify the NRC... dewatering operations, are equivalent to the resin being used at uranium recovery facilities (e.g. ISRs...

  17. 40 CFR 435.43 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... provided in 40 CFR 125.30-125.32, any existing point source subject to this subpart must achieve the... average shall not exceed 29 mg/l. Drilling Fluids, Drill Cuttings, and Dewatering Effluent: 1 (A) All..., and dewatering effluent SPP Toxicity Minimum 96-hour LC50. of the SPP Toxicity Test 4 shall be 3%...

  18. 78 FR 9575 - Marketing Order Regulating the Handling of Spearmint Oil Produced in the Far West; Change to...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-11

    ... 30, 1980 (45 FR 71759), Sec. 985.156 was added to the order's administrative rules and regulations..., 2012 (77 FR 57037). Copies of the rule were provided to the Committee, which in turn made it available... oil in order to derive a ``dewatered'' net quantity of oil produced. This dewatering process can...

  19. 77 FR 51832 - Atomic Safety and Licensing Board; In the Matter of Progress Energy Florida, Inc. (Levy County...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-27

    ..., Hearing, and Opportunity To Petition for Leave To Intervene, 73 FR 74,532, 74,532 (Dec. 8, 2008). \\3\\ A... wetlands, floodplains, special aquatic sites, and other waters, associated with dewatering, specifically: 1. Impacts resulting from active and passive dewatering; 2. Impacts resulting from the connection of the...

  20. 40 CFR 435.44 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... in 40 CFR 125.30-125.32, any existing point source subject to this subpart must achieve the following... Cuttings and Dewatering Effluent: 1 All facilities except Cook Inlet No discharge. Cook Inlet: Water-based drilling fluids, drill cuttings, and dewatering effluent Free Oil No discharge. 2 Non-aqueous...

  1. 40 CFR 435.44 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... in 40 CFR 125.30-125.32, any existing point source subject to this subpart must achieve the following... Cuttings and Dewatering Effluent: 1 All facilities except Cook Inlet No discharge. Cook Inlet: Water-based drilling fluids, drill cuttings, and dewatering effluent Free Oil No discharge. 2 Non-aqueous...

  2. 77 FR 13139 - Malheur National Wildlife Refuge, Harney County, OR; Draft Comprehensive Conservation Plan and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-05

    ... process for Malheur NWR. We started this process through a notice in the Federal Register (74 FR 31046...-O Units would be managed using rotational flooding and dewatering to enhance productivity for... include highly prescriptive grazing, mowing, farming, and extended dewatering to reclaim acres lost...

  3. An Experimental Investigation of Water Influence on Dry Forward In-situ Combustion 

    E-print Network

    Kudryavtsev, Philipp

    2013-10-08

    . Bitumen dewatering ......................................................................................... 19 II.4. Experimental procedure ................................................................................... 19 CHAPTER III EXPERIMENTAL... compressibility, psi-1 4.2*10 -7 Formation thermal conductivity, kJ/m3-oC 2,345 Oil saturation in tar rich zone, frac. 0.84 II.3. Bitumen dewatering Water content of the laboratory bitumen sample was measured with the Yamato® RE-71 rotary evaporator. A...

  4. 40 CFR 435.43 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... provided in 40 CFR 125.30-125.32, any existing point source subject to this subpart must achieve the... average shall not exceed 29 mg/l. Drilling Fluids, Drill Cuttings, and Dewatering Effluent: 1 (A) All..., and dewatering effluent SPP Toxicity Minimum 96-hour LC50. of the SPP Toxicity Test 4 shall be 3%...

  5. 40 CFR 421.152 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...of 7.5 to 10.0 at all times. (k) Beryl Ore Gangue Dewatering. BPT Limitations for the Primary Beryllium Subcategory...5 to 10.0 at all times. (l) Bertrandite Ore Gangue Dewatering. BPT Limitations for the Primary Beryllium...

  6. 40 CFR 421.154 - Standards of performance for new sources.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...of 7.5 to 10.0 at all times. (k) Beryl Ore Gangue Dewatering. NSPS for the Primary Beryllium Subcategory Pollutant...5 to 10.0 at all times. (l) Bertrandite Ore Gangue Dewatering. NSPS for the Primary Beryllium Subcategory...

  7. 40 CFR 421.152 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...of 7.5 to 10.0 at all times. (k) Beryl Ore Gangue Dewatering. BPT Limitations for the Primary Beryllium Subcategory...5 to 10.0 at all times. (l) Bertrandite Ore Gangue Dewatering. BPT Limitations for the Primary Beryllium...

  8. 40 CFR 421.152 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...of 7.5 to 10.0 at all times. (k) Beryl Ore Gangue Dewatering. BPT Limitations for the Primary Beryllium Subcategory...5 to 10.0 at all times. (l) Bertrandite Ore Gangue Dewatering. BPT Limitations for the Primary Beryllium...

  9. 40 CFR 421.154 - Standards of performance for new sources.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...of 7.5 to 10.0 at all times. (k) Beryl Ore Gangue Dewatering. NSPS for the Primary Beryllium Subcategory Pollutant...5 to 10.0 at all times. (l) Bertrandite Ore Gangue Dewatering. NSPS for the Primary Beryllium Subcategory...

  10. 75 FR 78985 - County of DuPage; Notice of Preliminary Permit Application Accepted for Filing and Soliciting...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-17

    ...with trash racks and one or two slide gates for isolating and dewatering the penstock; (3) an 870-foot-long, 28- foot-diameter...structure equipped with one or two slide gates for isolating and dewatering the tailrace tunnel; (8) a substation containing...

  11. 40 CFR 421.154 - Standards of performance for new sources.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...of 7.5 to 10.0 at all times. (k) Beryl Ore Gangue Dewatering. NSPS for the Primary Beryllium Subcategory Pollutant...5 to 10.0 at all times. (l) Bertrandite Ore Gangue Dewatering. NSPS for the Primary Beryllium Subcategory...

  12. 40 CFR 421.154 - Standards of performance for new sources.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...of 7.5 to 10.0 at all times. (k) Beryl Ore Gangue Dewatering. NSPS for the Primary Beryllium Subcategory Pollutant...5 to 10.0 at all times. (l) Bertrandite Ore Gangue Dewatering. NSPS for the Primary Beryllium Subcategory...

  13. 40 CFR 421.152 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...of 7.5 to 10.0 at all times. (k) Beryl Ore Gangue Dewatering. BPT Limitations for the Primary Beryllium Subcategory...5 to 10.0 at all times. (l) Bertrandite Ore Gangue Dewatering. BPT Limitations for the Primary Beryllium...

  14. Appalachian Clean Coal Technology Consortium: Technical progress report, October 1--December 31, 1995

    SciTech Connect

    1996-04-23

    In the dewatering project, two different approaches are taken. One approach involves displacing the water on the surface of coal by a hydrophobic substance that can be readily recovered and recycled. This novel concept, referred to as the Hydrophobic Dewatering (HD) process, is based on improved understanding of the surface chemistry of dewatering. The other approach is to use disposable dewatering substances in mechanical dewatering. The objectives of the proposed work are (1) to test the HD process on a variety of coals from the Appalachian coal fields, and (2) to identify suitable dewatering reagents that would enable mechanical dewatering to reduce the moisture to the levels satisfactory to electrical utilities and other coal users. The objective of the spiral separation project is to use computer modeling to develop better, more efficient spiral designs for coal cleaning. The fully-developed model will predict spiral performance based on variations in spiral profile, flow rate, and pitch. Specific goals are to: (1) design spirals capable of making separations at a specific gravity of 1.5, and (2) broaden the size range at which spirals make effective separations.

  15. Dewaterability of five sewage sludges in Guangzhou conditioned with Fenton's reagent/lime and pilot-scale experiments using ultrahigh pressure filtration system.

    PubMed

    Liang, Jialin; Huang, Shaosong; Dai, Yongkang; Li, Lei; Sun, Shuiyu

    2015-11-01

    Sludge conditioning with Fenton's reagent and lime is a valid method for sludge dewatering. This study investigated the influence of different organic matter content sludge on sludge dewatering and discussed the main mechanism of sludge conditioning by combined Fenton's reagent and lime. The results indicated that the specific resistance to filterability (SRF) of sludge was reduced efficiently by approximately 90%, when conditioned with Fenton's reagent and lime. Through single factor experiments, the optimal conditioning combinations were found. In addition, the relationship between VSS% and consumption of the reagents was detected. Furthermore, it was also demonstrated that the SRF and filtrate TOC values had a significant correlation with VSS% of sludge (including raw and conditioned). The main mechanism of sludge dewatering was also investigated. Firstly, it revealed that the dewaterability of sludge was closely correlated to extracellular polymeric substances (EPS) and bound water contents. Secondly, the results of scanning electron microscopy (SEM) stated that sludge particles were to be smaller and thinner after conditioning. And this structure could easily form outflow channels for releasing free water. Additionally, with the ultrahigh pressure filtration system, the water content of sludge cake conditioned with Fenton's reagent and lime could be reduced to below 50%. Moreover, the economic assessment shows that Fenton's reagent and lime combined with ultrahigh pressure filtration system can be an economical and viable technology for sewage sludge dewatering. Finally, three types of sludge were classified: (1) Fast to dewater; (2) Moderately fast to dewater; (3) Slow to dewater sludge. PMID:26253895

  16. Reducing the moisture content of clean coals

    SciTech Connect

    Raleigh, C.E. )

    1992-11-01

    Volume four contains the results of an Empire State Electric Energy Research corporation and Electric Power Research Institute (EPRI) funded investigation to evaluate the effects and economics of applying ultrasonic waves to commercial-scale dewatering and classifying of fine coal. Pre-treating minus 28 mesh Upper Freeport Seam coal using an ultrasonic tray device improved subsequent dewatering by a vacuum disc filter after thickening in a cyclone, but it did not improve dewatering by a screen-bowl centrifuge after cycloning. Dewatering of Pittsburgh Seam coal also improved when the coal was ultrasonically treated, but it only manifested during thickening in the cyclone. Cycloning also increased the removal of fine, high-ash content clay particles from Pittsburgh Seam coal. In contrast, ultrasonically-treating Upper Freeport Seam coal did not improve subsequent classifying by a rapped sieve bend. Based on a specific example of results in this test work for Upper Freeport Seam coal, using an ultrasonic tray to aid dewatering of finely-sized coal can be economically beneficial. For other coals and dewatering devices, however, the economics for using ultrasonic trays to enhance fine coal dewatering will differ.

  17. A Cultural Resources Survey for the Type V GG Liquid Waste Processing Facility in Washington County, Texas 

    E-print Network

    Moore, William

    2015-07-31

    area, a storage containment area, and a dewatering area. The unloading area will be supported by a concrete slab that is 385 square feet in size and 10 inches thick. The storage containment area will be supported by a concrete slab that is 2862... square feet in size and 10 inches thick. The dewatering area will be supported by a concrete slab that is 981 square feet in size and 10 inches thick. Concrete curbs will be constructed around the perimeter of the unloading and dewatering areas...

  18. 75 FR 20379 - Notice of Intent To Prepare an Environmental Impact Statement for the Proposed Hollister...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-19

    ...exploration. The full-scale project would augment the existing mine water management facilities that currently include a reverse-osmosis and desilting water treatment plant and rapid infiltration basins by adding underground dewatering wells and obtaining a...

  19. Quantifying the Carboxyl Group Density of Microbial Cell Surfaces as a Function of Salinity: Insights Into Microbial Precipitation of Low-Temperature Dolomite

    E-print Network

    Voegerl, Ryan Scott

    2014-08-31

    that carboxyl groups form a cell wall complex with Mg2+, dewatering the magnesium ion and overcoming kinetic barriers that allow dolomite formation at low temperature. Three microorganisms, two that precipitate dolomite in laboratory and field settings...

  20. Third technical contractors' conference on peat

    SciTech Connect

    Not Available

    1981-01-01

    The conference dealt with the estimation of US peat reserves, methods for the gasification of peat, including biogasification, techniques for dewatering peat, and the harvesting of peat. Separate abstracts were prepared for the individual papers. (CKK)

  1. From metallurgical coal tailings to thermal fuel

    SciTech Connect

    van den Broek, J.J.M.

    1982-01-01

    McIntyre Mines in Canada recover coal from washery tailings slurry. The tailings are dewatered in Bird screen bowl centrifuges and thermally dried in Joy Holo-Flite dryers. The coal recovered is burned in a power station.

  2. Potential for CO2 Sequestration and Enhanced Coalbed Methane Production, Blue Creek Field, NW Black Warrior Basin, Alabama 

    E-print Network

    He, Ting

    2011-02-22

    basin, Alabama. It considered the injection and production rate, the components of injected gas, coal dewatering, permeability anisotropy, various CO2 soak times, completion of multiple reservoir layers and pressure constraints at the injector...

  3. WINDROW AND STATIC PILE COMPOSTING OF MUNICIPAL SEWAGE SLUDGES

    EPA Science Inventory

    Research was conducted on composting anaerobically digested and centrifuge dewatered sewage sludge from 1975 through 1980. Windrow and static pile composting processes were evaluated; new methods were employed using deeper windrows and aerated static piles were constructed withou...

  4. MONITORING SEPTAGE ADDITION TO WASTEWATER TREATMENT PLANTS. VOLUME II. VACUUM FILTRATION OF SEPTAGE

    EPA Science Inventory

    The study examined the feasibility of using conventional vacuum filtration to dewater conditioned septage sludge, alone and in combination with thickened waste activated sludge. The septage was conditioned with aluminum sulfate, ferric chloride, and sulfuric acid, each used indep...

  5. 40 CFR 240.200-2 - Recommended procedures: Design.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...These include: Certain bulky wastes (e.g., combustible...and dewatered sludges from waste water treatment facilities, raw sewage sludges, and septic tank pumpings...designed to handle special wastes, special areas should be...

  6. 40 CFR 240.200-2 - Recommended procedures: Design.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...These include: Certain bulky wastes (e.g., combustible...and dewatered sludges from waste water treatment facilities, raw sewage sludges, and septic tank pumpings...designed to handle special wastes, special areas should be...

  7. 40 CFR 240.200-2 - Recommended procedures: Design.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...These include: Certain bulky wastes (e.g., combustible...and dewatered sludges from waste water treatment facilities, raw sewage sludges, and septic tank pumpings...designed to handle special wastes, special areas should be...

  8. 40 CFR 240.200-2 - Recommended procedures: Design.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...These include: Certain bulky wastes (e.g., combustible...and dewatered sludges from waste water treatment facilities, raw sewage sludges, and septic tank pumpings...designed to handle special wastes, special areas should be...

  9. 46 CFR 185.512 - Recommended emergency instructions format.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... in bilges. Use power driven bilge pump, hand pump, and buckets to dewater. (iii) Align fire pumps to... fixed extinguishing system if installed. (v) Maneuver vessel to minimize effect of wind on fire. (vi)...

  10. 46 CFR 185.512 - Recommended emergency instructions format.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... in bilges. Use power driven bilge pump, hand pump, and buckets to dewater. (iii) Align fire pumps to... fixed extinguishing system if installed. (v) Maneuver vessel to minimize effect of wind on fire. (vi)...

  11. Electrofiltration: An Energy Efficient Alternative in Solid-Liquid Separations 

    E-print Network

    Bollinger, J. M.; Adams, R. A.

    1984-01-01

    Electrofiltration has established itself as an energy efficient unit operation in ultrafine particle dewatering. The Dorr-Oliver Electrofilter combines vacuum cake filtration with electrophoresis and electroosmosis. This results in an order...

  12. 77 FR 57037 - Marketing Order Regulating the Handling of Spearmint Oil Produced in the Far West; Change to...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-17

    ... disposition. In a rule published on October 30, 1980 (45 FR 71759), Sec. 985.156 was added to the order's... the spearmint oil in order to derive a ``dewatered'' net quantity of oil produced. This...

  13. 30 CFR 784.25 - Return of coal processing waste to abandoned underground workings.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... the regulatory authority and the Mine Safety and Health Administration under 30 CFR 817.81(f). (b... the source of the hydraulic transport mediums, method of dewatering the placed backfill, retainment...

  14. EVALUATION OF BIOAEROSOL COMPONENTS, GENERATION FACTORS, AND AIRBORNE TRANSPORT ASSOCIATED WITH LIME TREATMENT OF CONTAMINATED SEDIMENT

    EPA Science Inventory

    Lime treatment has been used in contaminated sediment management activities for many purposes such as dewatering, improvement of physical properties, and reducing contaminant mobility. Exothermic volatilization of volatile organic compounds from lime-treated sediment is well kno...

  15. 46 CFR 182.500 - General.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...; see 46 CFR 175.600), instead of those of this subpart, provided that each watertight compartment forward of the collision bulkhead is provided with a means for dewatering. (c) Special consideration...

  16. 33 CFR 323.4 - Discharges not requiring permits.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... BMPs described in the State's approved program description pursuant to the requirements of 40 CFR 233... cyclical or intermittent temporary dewatering of such areas.) (iv) The discharges of dredged or...

  17. 76 FR 9594 - Notice of Availability of the Draft Northern Arizona Proposed Withdrawal Environmental Impact...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-18

    ... scoping for this project began on August 26, 2009 (74 FR 43152-43153), with publication of a Notice of... availability of uranium resources; Dewatering of perched aquifers and changes in water availability in...

  18. 33 CFR 323.4 - Discharges not requiring permits.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... BMPs described in the State's approved program description pursuant to the requirements of 40 CFR 233... cyclical or intermittent temporary dewatering of such areas.) (iv) The discharges of dredged or...

  19. 31. VIEW SOUTHEAST OF SHELTON LOCKS AND MITRE GATES DURING ...

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

    31. VIEW SOUTHEAST OF SHELTON LOCKS AND MITRE GATES DURING DEWATERING. - Ousatonic Water Power Company, Dam & Canals, CT Routes 34 & 108, 1 mile North of Derby-Shelton Bridge, Derby, New Haven County, CT

  20. 46 CFR 182.500 - General.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...; see 46 CFR 175.600), instead of those of this subpart, provided that each watertight compartment forward of the collision bulkhead is provided with a means for dewatering. (c) Special consideration...

  1. 30 CFR 784.25 - Return of coal processing waste to abandoned underground workings.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... the regulatory authority and the Mine Safety and Health Administration under 30 CFR 817.81(f). (b... the source of the hydraulic transport mediums, method of dewatering the placed backfill, retainment...

  2. 75 FR 51478 - Notice of Availability of the Draft Supplemental Environmental Impact Statement for the Cortez...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-20

    ... FR 57647). On December 3, 2009, the U.S. Court of Appeals for the Ninth Circuit partially reversed... Supplemental EIS to refine the analysis of potential air quality effects and the dewatering...

  3. 30 CFR 784.25 - Return of coal processing waste to abandoned underground workings.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... the regulatory authority and the Mine Safety and Health Administration under 30 CFR 817.81(f). (b... the source of the hydraulic transport mediums, method of dewatering the placed backfill, retainment...

  4. DESIGN INFORMATION REPORT: CENTRIFUGES

    EPA Science Inventory

    In the 1960s, manufacturers began to design centrifuges specifically for wastewater sludge applications. In addition, sludge thickening and dewatering processes were improved with the introduction of polyelectrolytes for chemical sludge conditioning. The report contains a brief d...

  5. 33 CFR 323.4 - Discharges not requiring permits.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... BMPs described in the State's approved program description pursuant to the requirements of 40 CFR 233... cyclical or intermittent temporary dewatering of such areas.) (iv) The discharges of dredged or...

  6. 30 CFR 784.25 - Return of coal processing waste to abandoned underground workings.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... the regulatory authority and the Mine Safety and Health Administration under 30 CFR 817.81(f). (b... the source of the hydraulic transport mediums, method of dewatering the placed backfill, retainment...

  7. 33 CFR 323.4 - Discharges not requiring permits.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... BMPs described in the State's approved program description pursuant to the requirements of 40 CFR 233... cyclical or intermittent temporary dewatering of such areas.) (iv) The discharges of dredged or...

  8. 45. Photograph of a published page. OPERATIONS IN 'H' OR ...

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

    45. Photograph of a published page. OPERATIONS IN 'H' OR DEWATERING BUILDING: HOLSTON DEFENSE CORPORATION. 'HOLSTON ARMY AMMUNITION PLANT.' Page 16. (no date). - Holston Army Ammunition Plant, RDX-and-Composition-B Manufacturing Line 9, Kingsport, Sullivan County, TN

  9. 46 CFR 182.500 - General.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...; see 46 CFR 175.600), instead of those of this subpart, provided that each watertight compartment forward of the collision bulkhead is provided with a means for dewatering. (c) Special consideration...

  10. WASTE ACTIVATED SLUDGE PROCESSING

    EPA Science Inventory

    A study was made at pilot scale of a variety of processes for dewatering and stabilization of waste activated sludge from a pure oxygen activated sludge system. Processes evaluated included gravity thickening, dissolved air flotation thickening, basket centrifugation, scroll cent...

  11. MUNICIPAL WASTEWATER SLUDGE COMBUSTION TECHNOLOGY

    EPA Science Inventory

    The publication describes and evaluates the various municipal sludge combustion systems. It also emphasizes the necessity for considering and evaluating the costs involved in the total sludge management train, including dewatering, combustion, air pollution control, and ash dispo...

  12. 46 CFR 182.500 - General.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...; see 46 CFR 175.600), instead of those of this subpart, provided that each watertight compartment forward of the collision bulkhead is provided with a means for dewatering. (c) Special consideration...

  13. 4. INTERIOR VIEW OF PORTSIDE PUMPROOM, DRYDOCK NO. 4, SHOWING ...

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

    4. INTERIOR VIEW OF PORTSIDE PUMPROOM, DRYDOCK NO. 4, SHOWING DEWATERING PUMP - U.S. Naval Base, Pearl Harbor, Dry Dock No. 4, West of State Route 92, West of Nimitz Gate, Pearl City, Honolulu County, HI

  14. 163. VIEW OF TWO JOHNS MINE PORTAL FROM EAST. NOTE ...

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

    163. VIEW OF TWO JOHNS MINE PORTAL FROM EAST. NOTE WATER LINE ON BRIDGE; DEWATERING MINE SUPPLIED A PORTION OF THE MILL'S WATER SUPPLY. - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

  15. 30 CFR 784.25 - Return of coal processing waste to abandoned underground workings.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... the regulatory authority and the Mine Safety and Health Administration under 30 CFR 817.81(f). (b... the source of the hydraulic transport mediums, method of dewatering the placed backfill, retainment...

  16. Modified approaches for high pressure filtration of fine clean coal

    SciTech Connect

    Yang, J.; Groppo, J.G.; Parekh, B.K.

    1995-12-31

    Removal of moisture from fine (minus 28 mesh) clean coal to 20% or lower level is difficult using the conventional vacuum dewatering technique. High pressure filtration technique provides an avenue for obtaining low moisture in fine clean coal. This paper describes a couple of novel approaches for dewatering of fine clean coal using pressure filtration which provides much lower moisture in fine clean coal than that obtained using conventional pressure filter. The approaches involve (a) split stream dewatering and (b) addition of paper pulp to the coal slurry. For Pittsburgh No. 8 coal slurry, split stream dewatering at 400 mesh provided filter cake containing 12.9% moisture compared to 24.9% obtained on the feed material. The addition of paper pulp to the slurry provided filter cake containing about 17% moisture.

  17. 77 FR 56817 - Notice of Public Hearings for the Draft Environmental Impact Statement for Medical Facilities...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-14

    ... August 19, 2011 (76 FR 51957). The DoN held two public scoping meetings on September 7, 2011 and... underground parking garage alternative would interact with groundwater and would require dewatering...

  18. Water Treatment Plant Sludges--An Update of the State of the Art: Part 2.

    ERIC Educational Resources Information Center

    American Water Works Association Journal, 1978

    1978-01-01

    This report outlines the state of the art with respect to nonmechanical and mechanical methods of dewatering water treatment plant sludge, ultimate solids disposal, and research and development needs. (CS)

  19. Fuel From Algae: Scaling and Commercialization of Algae Harvesting Technologies

    SciTech Connect

    2010-01-15

    Broad Funding Opportunity Announcement Project: Led by CEO Ross Youngs, AVS has patented a cost-effective dewatering technology that separates micro-solids (algae) from water. Separating micro-solids from water traditionally requires a centrifuge, which uses significant energy to spin the water mass and force materials of different densities to separate from one another. In a comparative analysis, dewatering 1 ton of algae in a centrifuge costs around $3,400. AVS’s Solid-Liquid Separation (SLS) system is less energy-intensive and less expensive, costing $1.92 to process 1 ton of algae. The SLS technology uses capillary dewatering with filter media to gently facilitate water separation, leaving behind dewatered algae which can then be used as a source for biofuels and bio-products. The biomimicry of the SLS technology emulates the way plants absorb and spread water to their capillaries.

  20. 76 FR 66747 - Notice of Availability of the Northern Arizona Proposed Withdrawal Final Environmental Impact...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-27

    ... effects to resources. Public scoping for this project began on August 26, 2009 (74 FR 43152), with... geologic conditions and availability of uranium resources; Dewatering of perched aquifers and changes...

  1. 78 FR 40496 - Notice of availability of the Final Environmental Impact Statement for the Proposed Hollister...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-05

    ... Project was available for review on June 1, 2012 (77 FR 32665). A 45-day comment period occurred. The BLM... adding underground dewatering wells and by obtaining a National Pollutant Discharge Elimination...

  2. SURVEY OF BAV (BIOLOGISCHE ABFALLVERWERTUNGS GESELLSCHAFT MBH & CO.) COMPOSTING PLANTS IN WEST GERMANY

    EPA Science Inventory

    An evaluation was made of within-vessel municipal sludge composting systems manufactured by Biologische Abfallverwertungs Gesellschaft mbH & Co. (BAV). The major components of the BAV system include sludge dewatering and storage, sawdust storage, recycled compost handling, materi...

  3. INACTIVATION OF INDIGENOUS VIRUSES IN RAW SLUDGE BY AIR DRYING

    EPA Science Inventory

    Air drying of raw sludge caused inactivation of indigenous viruses. A gradual loss of infectivity occurred with the loss of water until the solids content reached about 80%. A more rapid decline of viral infectivity occurred with further dewatering.

  4. 46 CFR 182.500 - General.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...; see 46 CFR 175.600), instead of those of this subpart, provided that each watertight compartment forward of the collision bulkhead is provided with a means for dewatering. (c) Special consideration...

  5. 28. Pump Room interiorMain valve control panel with status indicators ...

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

    28. Pump Room interior-Main valve control panel with status indicators for main flooding/dewatering valves and gates. - Hunters Point Naval Shipyard, Drydock No. 4, East terminus of Palou Avenue, San Francisco, San Francisco County, CA

  6. 33 CFR 323.4 - Discharges not requiring permits.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... BMPs described in the State's approved program description pursuant to the requirements of 40 CFR 233... cyclical or intermittent temporary dewatering of such areas.) (iv) The discharges of dredged or...

  7. IMPROVING DESIGN AND OPERATION OF HEAT TREATMENT/LOW PRESSURE OXIDATION SYSTEMS

    EPA Science Inventory

    The purpose of the investigation is to document possible improvements to design, operation, and maintenance of heat treatment and low pressure oxidation systems for conditioning sludge prior to dewatering in municipal wastewater treatment plants. The information in the report is ...

  8. 40 CFR 230.42 - Mud flats.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... extremely low tides and inundated at high tides with the water table at or near the surface of the substrate... dewater the mud flat or disrupt periodic inundation, resulting in an increase in the rate of erosion...

  9. Department of Civil & Environmental Engineering Geotechnical Group Seminar Series

    E-print Network

    Kamat, Vineet R.

    Department of Civil & Environmental Engineering Geotechnical Group Seminar Series University://www.umich.edu/~geotech/lecture.html Dewatering, Bypass Pumping, & Power Generation The Michigan Geotechnical Seminar Series is sponsored by

  10. Department of Civil & Environmental Engineering Geotechnical Group Seminar Series

    E-print Network

    Kamat, Vineet R.

    Department of Civil & Environmental Engineering Geotechnical Group Seminar Series University Dewatering Company ENR's top 600 The Michigan Geotechnical Seminar Series is sponsored by: SPARTAN is suited to a different application. This presentation considers these differences so that Geotechnical

  11. Department of Civil & Environmental Engineering Geotechnical Group Seminar Series

    E-print Network

    Kamat, Vineet R.

    Department of Civil & Environmental Engineering Geotechnical Group Seminar Series University://www.umich.edu/~geotech/lecture.html #1 Dewatering Company ENR's top 600 The Michigan Geotechnical Seminar Series is sponsored by: SPARTAN

  12. Department of Civil & Environmental Engineering Geotechnical Engineering Seminar Series

    E-print Network

    Kamat, Vineet R.

    Department of Civil & Environmental Engineering Geotechnical Engineering Seminar Series University geotechnical challenges for many historic power plants around the country. Several major failures occurred Brown Lab Dewatering, Bypass Pumping, & Power Generation The Geotechnical Engineering Seminar Series

  13. Department of Civil & Environmental Engineering Geotechnical Group Seminar Series

    E-print Network

    Kamat, Vineet R.

    Department of Civil & Environmental Engineering Geotechnical Group Seminar Series University Dewatering Company ENR's top 600 The Michigan Geotechnical Seminar Series is sponsored by: SPARTAN celebrated geotechnical engineering project of the last decades, owed to the high visibility of the structure

  14. Technologies for Reducing Nutrients in Dairy Effluent 

    E-print Network

    Mukhtar, Saqib; Wagner, Kevin; Gregory, Lucas

    2007-01-31

    Dairy operations are looking for new ways to meet new, higher standards set by the state for water quality. This publication explains research results on the effectiveness of two technologies -- a dewatering system and an electrocoagulation system...

  15. 46 CFR 134.170 - Operating manual.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...leg or leg pad. (10) A description, a diagram, operating guidance for the bilge system, and an alternative method of dewatering. (11) A general arrangement diagram showing the locations of— (i) Watertight and weathertight compartments;...

  16. 30 CFR 784.25 - Return of coal processing waste to abandoned underground workings.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...effects following backfilling. (c) The applicant shall describe the source of the hydraulic transport mediums, method of dewatering the placed backfill, retainment of water underground, treatment of water if released to surface streams, and the...

  17. 10 CFR 60.72 - Construction records.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...readings, and analysis; (9) Location and description of structural support systems; (10) Location and description of dewatering systems; and (11) Details, methods of emplacement, and location of seals used. [48 FR 28222, June 21,...

  18. 21 CFR 110.80 - Processes and controls.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... (10) Mechanical manufacturing steps such as washing, peeling, trimming, cutting, sorting and inspecting, mashing, dewatering, cooling, shredding, extruding, drying, whipping, defatting, and forming shall be performed so as to protect...

  19. 33 CFR 337.9 - Identification and use of disposal areas.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...existing policy, district engineers should also explore beneficial uses of dredged material, such as marsh establishment and dewatering techniques, in order to extend the useful life of existing disposal areas. Requests for water quality...

  20. 40 CFR 232.3 - Activities not requiring permits.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...rotation (e.g., the rotations of rice and soybeans) where such rotation results in the cyclical or intermittent temporary dewatering of such areas. (D) The discharge of dredged or fill material incidental to the emergency removal of sandbars,...