bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effect of anionic polyacrylamide molecular conformation and configuration on flocculation effectiveness
Authors: Caskey J. A. , Primus R. J. 
Published: February 2007

AbstractAnionic polyacrylamide was used to flocculate kaolin slurries. Both linear and branched polyacrylamide were polymerized. The polymer samples were fractionated and the molecular weights determined on the fractionated samples. The molecular weight range studied varied from 10,000 to 3,000,000. Each polyacrylamide sample was hydrolyzed to anionic levels ranging from 5 to 25 percent. The flocculating performance of the above polymers was measured on kaolin slurries using both settling tests with 3% kaolin and jar tests with 200 ppm kaolin. The effect of anionic polyacrylamide conformation on the flocculating rates was determined by varying the pH and hydrolysis level. The effect of the polymer configuration was studied by varying the molecular weight and using both linear and branched samples. In every case tested the linear polyacrylamide was a more effective flocculant than the branched polymer. The polyacrylamide effectiveness increased with increasing molecular weight for both the linear and branched samples tested. Increasing the mean end‐to‐end distance of the dissolved polymer molecular increased its flocculating effectiveness. This increased length could be accomplished by changing either the pH or the hydrolysis level. The results of the study were the same whether settling tests or jar tests were used as a performance criteria.
Environmental aspects of the combustion of sewage sludge in a utility boiler
Authors: Samela Daniel , Tsoumpas G. M. , Welshans G. K. , Zwillenberg M. L. 
Published: February 2007

AbstractThis paper discusses the environmental aspects of the combustion of dewatered municipal sewage sludge in a utility boiler. The information presented is based on the results of laboratory scale combustion tests performed on both sludge/coal and sludge/oil mixtures. Air pollution control and solid waste disposal considerations are discussed.
Cyclone efficiency and pressure drop correlations in oil shale retorts
Authors: Masin J. G. , Koch W. H. 
Published: February 2007

AbstractRecent experimental studies of cyclone performance at the severe process conditions usually present in shale retorts were used to test existing correlations for the prediction of cyclone collection efficiency and pressure drop. Modifying the correlations to include the effects of solids loading and particle saltation provides significantly better agreement between predicted and experimental values.
Steam‐regenerated activated carbon: An emission‐free, cost‐effective ground water treatment process
Authors: Parmele Charles S. , Allen Robert D. , Mehran Mohsen 
Published: February 2007

AbstractAir stripping is frequently selected over carbon adsorption with virgin carbon for the removal of halogenated and aromatic solvents from contaminated ground water because it is the cheaper process when the volatilized organics can be emitted. However, increasing concern over the impact of the organics vented from an air stripping process has created a situation where ground water treatment costs will be significantly higher unless a cost‐effective, emission‐free treatment process can be developed.IT has shown that an aqueous‐phase adsorption process using steam‐regenerated activated carbon is a proven, mature technology that should be considered for this application. This paper will describe the steam regeneration technology and its application and will compare the treatment costs for this approach with several other treatment technologies.
Control of SOx emissions by in‐furnace sorbent injection: Carbonates vs. hydrates
Authors: Newton G. H. , Harrison D. J. , Silcox G. D. , Pershing D. W. 
Published: February 2007

AbstractHigh temperature, isothermal data on SO2 capture by calcium based sorbents were obtained in a dispersed‐phase reactor for limestons, dolomites, hydrated calcitic limes, and hydrated dolomitic limes as a function of Ca/S molar ratio, temperature, and SO2 partial pressure. The experimental results indicate that SO2 capture is approximately linearly dependent on Ca/S molar ratio and relatively insensitive to SO2 partial pressure above 2000 ppm. SO2 capture is a strong function of general sorbent class; dolomitic sorbents are better than calcitic materials on an equivalent calcium basis and hydrated materials are more reactive than carbonates. Computer model predictions based on a grain formulation, available fundamental rate data, and measured surface areas accurately predict limestone performance; however, predicted capture for the hydrated sorbents is significantly below that measured experimentally. The measured capture results do, however, generally correlate with the BET surface areas measured when the sorbents were calcined in a muffle furnace at 980 K for 20 minutes with an inert environment.
Emissions control through dry scrubbing
Authors: Farber Paul S. 
Published: February 2007

AbstractConcern with operating problems, and the desire for system simplicity, has resulted in the development of dry scrubbing systems for flue gas cleanup, and their acceptance by industry as an alternate to the conventional wet scrubbers. These dry scrubbing systems incorporate two commonly used pieces of equipment; spray dryers, which have been used for many years to manufacture everything from detergents to powdered milk, and a particulates removal device (either a fabric filter or an electrostatic precipitator). The first application of this technology to removal of sulfur oxides from high sulfur coal combustion gases occurred when Argonne National Laboratory installed a system in 1981 as the control device on its main coal‐fired boiler. To date, this type of pollution control system has shown itself capable of meeting state emission standards and, in a special test run, of removing over 90% of the sulfur oxides produced from combustion of a coal with over 4% sulfur.
In situ aerobic biodegradation of aquifer contaminants at Kelly air force base
Authors: Heyse Edward , James Stephen C. , Wetzel Roger 
Published: February 2007

AbstractThis Air Force/EPA joint project tested in situ technology to treat a contaminated aquifer. The demonstration site is contaminated with a variety of organic wastes. Indigenous subsurface bacteria were used to degrade some of the organic wastes. Oxygen was supplied by a hydrogen peroxide solution.
Pilot testing of sodium thiosulfate
Authors: Chang John C. S. , Brna Theodore G. 
Published: February 2007

AbstractPilot plant tests have been conducted to evaluate sodium thiosulfate as an oxidation inhibition additive in five lime/limestone slurry flue gas desulfurization processes. It was found that the oxidation rate of absorbed sulfur dioxide (SO2) was reduced by more than 50 percent in the presence of 100 to 200 ppm of thiosulfate ion in the scrubbing slurry. Calcium sulfate dihydrate (gypsum) scaling was eliminated and the unsaturated (with respect to gypsum) operation mode was maintained by the addition of sodium thiosulfate. Other benefits of sodium thiosulfate addition observed at the pilot plant included improvement in solids dewatering properties for limestone processes and improvement in SO2 removal efficiency for magnesium‐enhanced lime/limestone processes.
Coal cleaning: Progress and potential
Authors: Livengood C. D. , Doctor R. D. 
Published: February 2007

AbstractResults from a detailed analysis of sulfur dioxide (SO)2reductions achievable through “deep” physical coal cleaning (PCC) at 20 coal‐fired power plants in the Ohio‐Indiana‐Illinois region are presented here. These plants all have capacities larger than 500 MWe, are currently without any flue‐gas‐desulfurization (FGD) systems, and burn coal of greater than 1% sulfur content (in 1980). Their aggregate emissions of 2.4 million tons of SO2per year represent 55% of the SO2inventory for these states. The principal coal supplies for each power plant were identified and characterized as to coal seam and county of origin, so that published coal‐washability data could be matched to each supplier. The SO2reductions that would result from deep cleaning (Level 4) and moderate cleaning (Level 3) of each coal were calculated using a PCC computer model. For deep cleaning, percentage reductions in sulfur content ranged from zero to 52%, with a mean value of 29%, and costs ranged from a low of $364/ton SO2removed to over $2000/ton SO2removed. Because coal suppliers to these power plants employ some voluntary coal cleaning, the anticipated emissions reduction from current levels if deep cleaning were used should be near 20%. These emissions reductions were projected using conventional coal‐cleaning‐circuit designs. The basic elements of typical commercial PCC designs are briefly described, and current research and development activities in physical, chemical, and biological desulfurization of coal are reviewed. Possible governmental actions to either encourage or mandate coal cleaning are identified and evaluated.
Electrogenerative and related electrochemical methods for NOx and SOx control
Authors: Langer Stanley H. , Foral Michael J. , Colucci José A. , Pate Kevin T. 
Published: February 2007

AbstractElectrogenerative processes can be used to reduce nitric oxide to low levels in a variety of gas streams. An approach for applying these and related electrochemical reduction processes to selectively reduce NOx concentrations in power plant effluents is discussed. Both electrogenerative oxidation and reduction of sulfur dioxide can occur. However, oxidation of sulfur dioxide to sulfuric acid seems to be the most feasible route for incorporation into an electrochemical flue gas treatment which might also produce useful chemicals. A strategy for implementing an “electrochemical scrubbing” procedure is described.
Treatment of a landfill leachate in powdered activated carbon enhanced sequencing batch bioreactors
Authors: Ying Wei‐chi , Bonk Robert R. , Sojka Stanley A. 
Published: February 2007

AbstractAddition of powdered activated carbon (PAC) significantly improved treatment of a chemical waste landfill leachate in sequencing batch bioreactors (SBRs). Concentrations for many of the monitored halogenated organic compounds in the effluent were below their respective detection limits. Excellent treatment efficiency was achieved under a variety of operating conditions: wastewater composition, feed rate, hydraulic retention time, organic loading, PAC dosages, biomass and PAC concentrations in the bioreactors. The PAC‐SBR performance was unaffected when wastewater feeding was suspended during weekends and holidays. The PAC‐SBR treatment cost is much lower than either that of the conventional granular activated carbon adsorption technology or the two‐stage process of biodegradation and carbon treatment.
Evaluation of sorbents and additives for dry SO2 removal
Authors: Jorgensen Claus , Chang John C. S. , Brna Theodore G. 
Published: February 2007

AbstractBench scale studies of the reaction between sulfur dioxide and alkaline sorbents were performed in an integrated fixed bed reactor at low temperature, simulating the fabric filter dust layer of dry FGD systems with SO2 laden gas passing through it. Three major groups of sorbent were tested: calcitic and dolomitic hydrated lime, sodium bicarbonate, and limestone (calcite aragonite) with salt additives such as CaCl2, Ca(NO3)2, and NaNO3. Relative humidity significantly affected SO2 absorption by lime and limestone plus additives, but had less impact on NaHCO3 reactivity. Different reaction patterns for various sorbents were observed: the SO2/hydrated lime reaction rate was reduced with conversion of the sorbent, resulting in limited lime utilization, whereas the reactions between SO2 and NaHCO3 and SO2 and CaCO3 plus additives seem to proceed a constant rate, potentially leading to high sorbent utilizations. Results are discussed relating to sorbent screening for dry FGD systems.
De‐Emulsification of complex petroleum emulsions by use of microbial biomass
Authors: Kosaric N. , Duvnjak Z. , Cairns W. L. 
Published: February 2007

AbstractIt has been demonstrated in this laboratory that specific organisms are capable of breaking both o/w and w/o petroleum derived emulsions. Specific bacteria have been selected and have been tested on model (kerosene/water) and on complex field emulsions obtained during enhanced oil recovery trials (w/o) and in tar sands extraction process (o/w).More recent studies involve the use of microbial biomass (sludge) from municipal and refinery waste water treatment processes as the de‐emulsifying agents for treatment of these emulsions.The results indicate that either pure microbial cultures or microbial waste biomass can be used to efficiently break industrial emulsions. This approach is a novel application and is a promising alternative to use of chemically synthesized industrial de‐emulsifying agents.
The pilot‐scale demonstration of the MODAR oxidation process for the destruction of hazardous organic waste materials
Authors: Staszak Carl N. , Malinowski Kenneth C. , Killilea William R. 
Published: February 2007

AbstractCECOS International, Inc., a hazardous waste treatment and disposal firm headquartered in Buffalo, New York, and MODAR, Inc. of Houston, Texas, conducted a field, pilot‐scale demonstration of the MODAR Oxidation Process for the destruction of hazardous organic waste materials in 1985.The MODAR Oxidation Process utilizes water at conditions above its critical point (647K and 22.1 MPa) as the reaction medium for the oxidation of organic materials. The products of this oxidation reaction, for a typical organic material, are carbon dioxide and water. Any halogen present as part of the organic matrix is converted to its halo‐acid form. Two waste streams were destroyed in the field tests. These were an aqueous‐based waste contaminated with several organic EPA priority pollutants, and an organic transformer dielectric fluid contaminated with polychlorinated biphenyls (PCBs). In both tests, water constituent concentrations in liquid and gas process effluents were below analytical detection limits. Destruction efficiencies based on influent concentrations and the reported detection limits were greater than “four nines”. The results of the demonstration have shown the process' ability to destroy toxic and persistent organic contaminants in liquid wastestreams without producing hazardous by‐products.
Chemistry of a flue gas combined NOX and SO2 scrubber employing ferrous cysteine additives
Authors: Tu M. D. , Chang S. G. 
Published: February 2007

AbstractUse of ferrous cysteine additives in flue gas scrubbing systems creates a different and simpler scrubber chemistry compared to Japanese processes using ferrous chelates such as Fe2+ (EDTA). Instead of being converted to nitrous oxide, nitric oxide in flue gas can be concentrated and/or reduced to nitrogen gas. Also, production of dithionate ions and nitrogen‐sulfur compounds in scrubbing systems can be avoided. Fixation of nitric oxide occurs by a rapid reaction with the ferrous cysteine complex, at pH between 7.5 and 6.5, to form solid cystinatodinitrosyl iron (II), which releases NO upon heating. Most of the NO is reduced to gaseous species, primarily N2, in ferrous cysteine solutions at pH 10. Cysteine can rapidly reduce ferric ion to ferrous ion while being oxidized to cystine. Cystine can be reduced back to cysteine by SO2.
Removal of radioactive contaminants from West Valley waste streams using natural zeolites
Authors: Grant D. C. , Skriba M. C. , Saha Anuj K. 
Published: February 2007

AbstractA variety of low‐level radioactive waste streams are being generated from the decontamination and decommissioning of the former nuclear fuel reprocessing plant at West Valley, New York. It is presently planned to remove the radioactive contaminants from the solutions by ion exchange. Natural zeolites, such as clinoptilolite, erionite, chabazite, and phillipsite, were felt to provide desired flexibility and capacity under varying conditions. Batch and column testing were conducted on these materials using representative waste streams containing radioactive cesium, strontium, and cobalt. Sorption coefficients, dynamic decontamination factors, capacity, and sorption kinetics were determined. In addition, testing was conducted on prepared zeolites (i.e., Linde IE‐95 and A‐51) to provide comparative data.
Activated carbon adsorption of heavy metal chelates from single and multicomponent systems
Authors: Bhattacharyya D. , Cheng C. Y. Raymond 
Published: February 2007

AbstractAn extensive experimental investigation was conducted with activated carbon to establish the adsorption (equilibrium and kinetics) behavior of several metals from single and two metals systems in the presence of complexing agents. Triethylenetetramine (TRIEN) and EDTA were used as complexing agents. The extent of adsorption was found to be a function of metal and ligand types, ligand to metal ratio, pH, and metal chelate species distribution. Selective separation of valuable metals can also be achieved by the addition of complexing ligands to a mixture of strongly complexable metal (such as Cd2+ and Ni2+) and weakly complexable metal (such as Ba2+ and Ca2+).
Rapid renovation of a sludge lagoon
Authors: Dienemann E. A. , Magee J. F. , Kosson D. S. , Ahlert R. C. 
Published: February 2007

AbstractThe application of a soil‐based microbial tratment process for renovation of natural leachate and forced extracts from an industrial sludge lagoon has been examined. Laboratory soil column experiments, with influent TOC concentrations up to 2270 mg/l, obtained reductions in dissolved organic carbon that ranged from 90% to 99%. Previous work indicates that these results can be extrapolated to field conditions.
Destruction of volatile organic compounds via catalytic incineration
Authors: Tichenor Bruce A. , Palazzolo Michael A. 
Published: February 2007

AbstractThis paper reports results from an EPA‐funded study designed to investgate the effect of catalytic incinerator design and operation on the destruction of specific volatile organic compounds (VOC), both singly and in mixtures. A range of operating and design parameters were tested with a wide variety of compounds and compound mixtures. Results from the study showed that key variables affecting destruction included operating conditions (temperature, space velocity, catalyst geometry and catalyst volume), VOC composition and VOC concentration. Significant differences in destruction efficiency were found for some compounds when tested alone compared to when tested in mixtures.
Biooxidation of coal gasification wastewaters using fluidized‐bed bioreactors
Authors: Donaldson Terrence L. , Strandberg Gerald W. , Hewitt Jimmie D. , Shields Glenna S. , Worden R. Mark 
Published: February 2007

AbstractProcess condensate wastewaters from two fixed‐bed gasifiers have been treated successfully using a laboratory‐scale, fixed‐film, fluidized‐bed bioreactor. Both dilute (1 to 2% raw wastewater) and more concentrated (50% stripped wastewater) were treated continuously for periods of one to three months. Biological activity was stable, recovery from upsets was rapid, and reaction rates were high due to the high concentration of microorganisms retained on the support particles. Removal of phenolics exceeded 99%, and removal of chemical oxygen demand was typically 75 to 85% for the 50% stripped wastewater with a hydraulic residence time in the bed of ˜5 to 7 h. Sludge production rates were comparable to rates in suspended growth systems.
Ozonolysis of organic compounds in a two‐phase fluorocarbon‐water system
Authors: Stich Frank A. , Bhattacharyya D. 
Published: February 2007

AbstractOzone, due to its characteristics as a powerful oxidant, has found use in the destruction of toxic organic compounds in wastewater. Its use has been limited however, because of ozone's rapid decomposition and low solubility in water. The ozonation process may be more efficiently carried out in a two‐phase system. The second phase consists of a reusable, fluorinated hydrocarbon, with an ozone solubility of 12–14 times that of water. The fluorinated solvent serves as both an ozone source and a non‐aqueous phase in which the oxidation occurs. With this novel two‐phase process, it is also possible to perform selective oxidation. The experimental results are presented for organic compounds such as phenol, naphthol, etc. The extent of degradation is measured in terms of pH changes, HPLC, and TOC.
Recent changes in superfund policy and guidance: Alternative technology
Authors: Zamuda Craig D. 
Published: February 2007

AbstractEngineering practices applicable to Superfund sites, as viewed in the context of the institutional policies that guide them are discussed below. Past practice has relied heavily on land disposal of wastes removed from uncontrolled hazardous waste sites. The requirements of the 1984 Hazardous and Solid Waste Amendments (HSWA) to the Resource Conservation and Recovery Act however, have caused land disposal to be the option of last choice. Indeed, the HWSA's general policy directives have established the overall environmental goal of drastically reducing dependence on land disposal for all forms of hazardous waste. As a result, a new set of waste treatment/disposal priorities has been implemented for Superfund site Remedial Actions. The first priority is reuse or recycling of waste, the second is waste destruction, and the third is waste immobilization. The paper outlines the steps for selecting waste treatment processes for Superfund sites and distinguishes between in situ and mobile technologies.
Fugitive emissions from the ethylene oxide production industry
Authors: Berglund Ronald L. , Romano Robert R. , Randall John L. 
Published: February 2007

AbstractAs new programs are initiated by industry and federal or state regulatory agencies to reduce releases of hazardous air pollutants and reactive volatile organic compounds into the atmosphere, there are increasing questions over the loss of organic compounds from fugitive sources, the best method to estimate these losses, and the factors that influence these losses. The presently established method is to use generalized emission factors for each specific piece of equipment comprising a process unit. The accuracy of the estimates obtained using the available emission factors depends upon two features. These are first, the precision and accuracy of the actual emission factors or correlations themselves, and second, the resemblance of the systems from which the correlations were developed to those for which they will be applied.
Air stripping of volatile hydrophobic compounds using packed crisscross flow cascades
Authors: Wood Dianne F. , Locicero Larry L. , Valsaraj Kalliat T. , Harrison Douglas P. , Thibodeaux Louis J. 
Published: February 2007

AbstractThe removal of four volatile organic compounds from aqueous solution by air stripping using a cascade crossflow device has been studied. This method of operation gave mass transfer coefficients and removal efficiencies quite similar to those achieved in conventional countercurrent operations. However, in terms of reduced pressure drops and greater range of stable operation, the advantages of the cascade crossflow device far outweigh those of the conventional countercurrent stripper.
Chitosan in crab shell wastes purifies electroplating wastewater
Authors: Coughlin Robert W. , Deshaies Michael R. , Davis Edward M. 
Published: February 2007

AbstractChitosan, a polyglucosamine, can be formed by de‐acetylating chitin, a major structural component of crustacean shells. Crab shell particles were treated and deacetylated to elaborate chitosan on their outer peripheries. Experimental data and an approximate preliminary economic analysis are presented to show the potential of using treated crab shell waste for purifying electroplating rinsewater. This approach is compared with currently used precipitation technology for removing metal ions.