bluuebunny/crossref_metadata_2025_split huggingface dataset:
The assessment of risk at superfund sites
Authors: Lincoln David 
Published: February 2007

AbstractRisk assessments are one component in the evaluation of potential impacts of remedial alternatives at Superfund sites. They inherently involve uncertainty and incomplete scientific understanding. There is general agreement in the risk assessment community on the broad categories of activities to be performed (i.e., exposure, hazard, and risk assessments), but the method of analysis for each element within an activity is presently not uniformly established. The objective of this paper is to describe judgmental decisions that must be made by the risk assessors during the design and execution of a Superfund site assessment, with a focus on the issues of uncertainty and exposure scenarios. The assessment at Western Processing, Washington, is used as an example of the substantial expert judgment required in choosing the analytical methods and appropriate assumptions.
Prediction of organic chemical fates in biological treatment systems
Authors: Blackburn James W. 
Published: February 2007

AbstractAttention is presently being focused on the fates of organic chemicals in biological treatment systems. Most systems have been designed and operated to remove organic compounds from the aqueous waste stream and performance has been defined in terms of removal of a non‐specific parameter from the wastewater. Parameters like total organic carbon, biochemical oxygen demand, and chemical oxygen demand have historically been used in treatability studies, in system design, and in determining system performance. Performance data using these approaches are inadequate for determination of the removal of specific compounds unless (fortuitously) the specific compound's biological activity is approximated by the generalized activity of the non‐specific parameter.The resulting assumption that the biokinetics, and therefore the fate of organic compounds, are similar and well‐described by the biokinetics of the non‐specific parameter does not hold for specific chemicals that possess strong stripping/volatilization and/or biomass sorption tendencies or for compounds that have biotransformation kinetics that differ from the idealized “BOD‐like” compound.Some compounds are likely to preferentially strip/volatilize or sorb onto biomass either if generally recalcitrant to biotransformation, or if the biotransformation process is variable and the rates of the competitive fate mechanisms are large relative to the low transient biotransformation rate. All of the above cases have been experimentally documented and will be discussed. The biotransformation rates have the greatest magnitude of variation of any fate‐related parameter and therefore have a major influence on the compound fate. An equation coupling the competitive fates of organic chemicals in completely‐mixed and steady‐state biological treatment systems has been developed and is presented. This equation can be arranged to allow calculation of the fraction or percentage of an organic compound fed to a system that strips, sorbs onto biomass, biotransforms, or remains in the effluent if the stripping, sorption, and biotransformation rates are known. It can be used to correct experimental data to account for the competitive mechanisms and generate more reliable biotransformation data. Finally, it also serves as a unifying approach against which the specific fate performance of a given system may be compared. Therefore it may be used to estimate potential organic air emissions and the potential of toxic organics in sludge generated from the biological waste treatment process.
Managing hazardous waste risks under the Massachusetts “Superfund” law
Authors: Paulsen Frederick S. 
Published: February 2007

AbstractDifferent options and strategies for managing hazardous waste risks are presented. Experience in Massachusetts under a state “Superrfund” law (Chapter 21E) as applied to the selling, buying, and financing of real estate is drawn upon.The sites in question are not “Superfund” sites. They are those commonly found in a state with a history of many old industries as well as with the expected number of gas stations with underground tanks. The approach discussed is that with a thorough site assessment involving historical research and if required, soil and ground water examination, the parties (sellers, buyers, and lenders) through use of a variety of special devices may successfully consummate real estate transactions. These devices include use of indemnification agreements, escrow funds, title insurance, and in some cases involve accomplishment of tank and contaminated soil removal before closing the real estate transaction.Not following this course of action exposes some or all of the parties to the risk of liability for cleanup costs as well as for claims by other parties to the transaction.
Intermedia transport of organic compounds in biological wastewater treatment processes
Authors: Barton Douglas A. 
Published: February 2007

AbstractOrganic compounds present in many industrial effluents are transported to varying extents to the gaseous or solid phase, in addition to potential biodegradation, during treatment. Knowledge of the fate of such compounds is critical for making valid policy and engineering decisions regarding issues such as the disposal of sludges, effluent toxicity, and emissions to the ambient air. To quantify the relative distribution of the fate of selected groups of compounds, a mathematical model is presented which describes the intermedia transport mechanisms including volatilization, solids sorption, and biodegradation. The extent of removal via each modeled pathway is a function of the physical properties of the specific compound and the process design and operational parameters of the system.
Prediction of activated carbon adsorption performance under high relative humidity conditions
Authors: Keener Tim C. , Zhou Derong 
Published: February 2007

AbstractHumidity effects on carbon adsorption were investigated using five volatile organic compounds (VOCs). Relative humidities ranged from 54% to 92%. Under these high relative humidity conditions, the Dubinin–Polanyi equation was used to analyze the results of activated carbon adsorption capacity. Based on the Dubinin–Polanyi equation and the concept of a mass transfer zone, an adsorption kinetic equation was derived to predict the carbon adsorption (MTZ) velocity and the adsorbate concentration profile in the bed.
The impact of internal phosphorus loading on the restoration of Trout lake
Authors: Goetzman Jeffrey S. 
Published: February 2007

AbstractThe accelerated eutrophication of many lakes by society is a problem of increasing concern. The increase in photosynthetic productivity may decrease water clarity, alter dissolved oxygen profiles, and decrease the aesthetic value of a lake. For those lakes which possess high levels of water quality, the need for lake management arises. The first step in developing management techniques for any lake is to collect baseline data—primarily measurements of temperature, dissolved oxygen, transparency, and calculation of a lake's morphometric parameters. Beaulac, Reckhow, and Simpson (1980) [1] indicate that the analysis of lake water nutrient concentration (phosphorus/nitrogen) and calculation of annual nutrient budgets are important additions to baseline data. By studying a lake and its watershed, relationships fundamental to the development of lake prediction models may be determined which operate as a function of nutrient–related parameters such as the areal phosphorus and water loading to a lake.Quantitative changes in phosphorus loading can be interpreted to provide changes in lake water phosphorus concentration and subsequently trophic status. Predictions made through the use of such models serve as a basis for management decisions.
Separation of hazardous organics by reverse osmosis membranes
Authors: Williams M. , Deshmukh R. , Bhattacharyya D. 
Published: February 2007

AbstractExtensive experimental studies showed that thin‐film, composite membranes can be used effectively for the separation of selected hazardous organic compounds. This waste treatment technique offers definite advantages in terms of high solute separations at low pressures (<2 MPa) and broad pH operating range, and the use of charged membrane would allow the selective separation of some organics from feeds containing high salt concentrations. In addition, feed pre‐ozonation of selected organics has been shown to provide significant improvement in flux and rejection characteristics for both charged and uncharged membranes due to formation of ionizable organic acid intermediates during the ozonation that do not interact as strongly with the membrane. It has been shown that the overall ozonation–membrane process could be greatly effective in producing permeate water of high quality while minimizing the volume of waste that must be further treated. Batch adsorption studies were also utilized to understand the membrane flux drop phenomena in non‐ozonated solutions.
Supercritical CO2‐cosolvent extraction of contaminated soils and sediments
Authors: Dooley Kerry M. , Ghonasgi D. , Knopf F. Carl , Gambrell Robert P. 
Published: February 2007

AbstractDDT‐ or PCB‐contaminated topsoils of high organic content were extracted using supercritical CO2 or CO2‐5 wt% cosolvent (toluene, acetone, methanol, acetic acid, diethylamine) mixtures at 313 K and 101 bar. In separate experiments, the pure contaminants were dissolved in supercritical CO2 at the same conditions and the equilibrium solubilities determined. Most of the cosolvents only marginally improve extraction rates over the case of pure CO2. Methanol, however, increases total amounts of DDT removal from 50–80% to > 95%, and increases DDT and PCB extraction rates by as much as an order of magnitude. Methanol is a superior cosolvent probably because its hydrogen‐bonding ability is better suited to interaction with the organic matter in the soil (humic acids, fulvic acids, polysaccharides); the organic matter essentially “dissolves” the contaminants in the soil matrix. Comparing a simple fixed–bed, local equilibrium (based on pure contaminant equilibria) desorption model to the actual desorption data indicates that contaminant solubilities in supercritical fluids are enhanced (over the pure contaminant case) when desorbing from soils. The enhancements may be related to the simultaneous desorption of other low molecular‐weight organics from the soils.
Heterogeneous photocatalysis for water purification: Contaminant mineralization kinetics and elementary reactor analysis
Authors: Ollis David F. , Turchi Craig 
Published: February 2007

AbstractHeterogeneous photocatalysis is the third and newest of an emerging series of photolytic technologies for water treatment and purification. The earlier examples of ultraviolet ozonation and ultraviolet peroxidation involved direct photoactivation of the contaminant and/or dissolved oxidant and are dominated by solution phase chemistry. Photocatalysis, in contrast, involves photoactivation of the heterogeneous catalyst (an example of indirect photochemical processes) and is dominated by reaction events initiated at the catalyst surface. This paper summarizes (1) current rate equations for photocatalyzed simultaneous destruction of multiple oxidizable organic contaminants and (2) simplified convective transport equations appropriate to photoreactor design under various degrees of fluid mixing and simultaneous reaction contributions by heterogeneous (photocatalyzed) as well as homogeneous reactions.
Feasibility of using alginate to absorb dissolved copper from aqueous media
Authors: Jang L. K. , Brand W. , Resong M. , Mainieri W. , Geesey G. G. 
Published: February 2007

AbstractAlginate (a biopolymer from kelp and some bacterial strains) is known to absorb copper favorably in the presence of other cations. In this work, the feasibility of using a 2‐liter batch three‐phase (air/liquid/alginate gel) loop fluidized bed reactor to polish water containing 10–150 ppm dissolved copper was investigated. Three methods were tested: (1) Calcium alginate spheres, prepared by dispensing sodium alginate (3.2 wt. % in water) into a 0.05 M calcium nitrate solution, were used as the absorbent, (2) the alginate spheres were formed in situ by dispensing the sodium alginate solution directly into the reactor fluid, and (3) same as (2) except that a trace amount of EDTA was added to the alginate solution. Batch absorption data showed that Method 3 yielded the best result; the concentration of dissolved copper was successfully reduced from 140 ppm to 10 ppm with 3.2 g sodium alginate and 0.2 g EDTA used. However, when the initial concentration was below 40 ppm, both Method 2 and Method 3 are not recommended because the concentration of dissolved copper was too low to allow in situ formation of alginate spheres. Method 1 was found to be useful for treating water containing 10 ppm dissolved copper. But the competition from calcium seriously affected the effective capacity of the alginate for copper. The application of the classical shell progressive model to describe the absorption kinetics was discussed.
Oxygen membrane electrode used as a toxicity biosensor
Authors: Goldblum David K. , Holodnick Steven E. , Mancy Khalil H. , Briggs Dale E. 
Published: February 2007

AbstractThree biosensor configurations that included a dissolved oxygen electrode and yeast cells (Saccharomyces cerevisiae) were evaluated as a means to assess the environmental effects of toxic chemicals. The configurations were: closed suspension—assay medium closed to air and cells suspended in the medium; open suspension—assay medium open to air and cells suspended in medium; and biofilm electrode (BFE)—assay medium open to air but cells immobilized on the surface of the electrode. The BFE was the most advantageous configuration based on assay times and detection limits.
Development of an immobilized microbe bioreactor for VOC applications
Authors: Friday David D. , Portier Ralph J. 
Published: February 2007

AbstractIn this paper, the technical challenges to building a bioreactor capable of removing significant amounts of chlorinated VOCs (ethylene dichloride specifically) from groundwater or wastewater effluents is discussed. Key considerations include appropriate construction materials, selection of a low cost microbial immobilization support, identification of microorganisms with high VOC metabolic uptake rates, reactor instrumentation and control system, optimum reactor mixing environment, and reactor aeration methods. Operation configuration and techniques to maximize performance in a 75‐liter pilot reactor are presented with field performance data.
New storm water regulations impact industry
Authors: Gemar Claudia 
Published: February 2007

AbstractIn November 1990, new Environmental Protection Agency (EPA) regulations aimed at governing the discharge of storm water from industrial facilities became effective. Because some industrial runoff contains toxics and other pollutants, the EPA considers storm water a major source of water contamination. The new regulations will have a profound impact on the National Pollutant Discharge Elimination System (NPDES) permit requirements for industry. This paper summarizes the new storm water regulations, focusing on the requirements for industrial facilities. It also presents suggestions for compliance.
Development of a transportable thermal separation process
Authors: Ayen Richard J. , Swanstrom Carl 
Published: February 2007

AbstractA new process for remediation of organics‐contaminated soils and sludges has been developed. The process consists of a soil dryer and a gas separation system. The dryer heats the soil indirectly to 200–450°C in a rotary kiln, volatilizing the water and organic contaminants. No oxygen is present, and no organic destruction or incineration occurs. The dry treated soil discharged from the dryer is used for backfill at the site. The gas separation system condenses and collects the volatilized contaminants. The vapors are first sent to a water spray scrubber to remove the dust, then are cooled with heat exchangers to about 4°C to condense the water and organics. The water is treated and used to wet the cleaned soil or discharged, as appropriate, while the organics are shipped offsite for later treatment. Most of the remaining gas is reheated and recycled to the dryer. The gas not recycled is cleaned and vented. Development has progressed from laboratory and pilot units to a full commercial scale unit capable of processing 115 metric tons per day of soil with 20% moisture. Soil contaminants effectively removed include polychlorinated biphenyls (PCBs), petroleum hydrocarbons and chlorinated hydrocarbons.
Limiting emissions of the greenhouse gas, CO2
Authors: Simpson Theodore B. 
Published: February 2007

AbstractWhile considerable global warming uncertainties remain, limiting the emission of the greenhouse gas, CO2 at minimum cost is a growing social concern. An approach suggested is to genearte electricity by processes that facilitate capture of the CO2, and then to compress and inject it into suitable underground formations. By using formations containing uneconomical deposits of energy sources such as oil, gas, Fe+ +, coal, etc., underground bioconversion of the CO2 to recoverable fuel forms may prove possible.
Estimation of VOC emissions using the BASTE model
Authors: Corsi Richard L. , Card Thomas R. 
Published: February 2007

AbstractEmissions of volatile organic compounds (VOCs) from wastewater raises concerns as many VOCs are photochemically reactive and contribute to the formation of tropospheric ozone, and may be toxic with subsequent adverse affects on human health. Many municipal wastewater treatment facilities (WWTFs) and industries are, or will be, required to complete extensive VOC emissions inventories. Accurate VOC emission models are desirable to facilitate such inventories, and to serve as alternatives to resource‐intensive air sampling at all processes within WWTFs. A flexible VOC fate model (Bay Area Sewage Toxics Emissions: BASTE) has been developed to simulate a wide range of treatment configurations within WWTFs. In addition to its ability to simulate complex treatment trains, BASTE has several features not found in existing VOC fate models. These features include the ability to (1) simulate covered treatment processes, (2) mix mechanistic emissions estimates with emissions measurements and empirical emission factors, and (3) incorporate measured dissolved oxygen concentrations as surrogate measures of VOC emission potential.
NOx reduction by the Econ‐Nox™ SCR process
Authors: Hardison L. C. , Nagl G. J. , Addison G. E. 
Published: February 2007

AbstractSCR systems are used extensively in Japan and West Germany to eliminate 80–90% NOx emissions from utility boilers and industrial furnance stacks. Costs have been lowered considerably over the past ten years. Further reduced costs and stringent regulations on NOx emission make this simple system attractive for refinery and industrial process heaters, boilers, and gas turbines.The Econ‐NoxTM process uses a fluidized catalyst bed to accomplish selective total reduction of oxides of nitrogen to elemental nitrogen using ammonia as a reactant. The process can be designed for operating temperatures between 550°F and 750°F and for a wide range of operating variables.The process brings together some old technology on selective reduction chemistry, relatively new fluidized bed oxidation techniques and a non‐precious metal Econ‐AcatTM catalyst which permits operation over a broader temperature range than has been practical in the past.This paper reports some of the distinctions made between this reactor configuration and the historical thermal and catalytic systems used for this type of process.
A Confined Vortex Scrubber for fine particulate removal from flue gases
Authors: Loftus Peter J. , Stickler David B. , Diehl Richard C. 
Published: February 2007

AbstractAn innovative cleanup concept, based on a Confined Vortex Scrubber (CVS), for fine particulate removal from combustion flue gases has been developed, tested and verified. The CVS consists of a cylindrical vortex chamber with multiple tangential flue gas inlets. The clean gas exit is via two central tubes. Water is introduced into the chamber and is confined within the vortex chamber by the extremely high centrifugal forces generated by the gas flow. The confined water forms a layer through which the flue gas is forced to bubble. Due to the high radial acceleration, the bubbles generated are very small, leading to a strong gas/liquid interaction, high inertial separation forces and extremely efficient fine particle cleanup. Collection efficiencies in excess of 99.5 percent have been measured for extremely fine fly ash (mean particle size 3 microns). A collection efficiency of 98 percent has been measured for 0.3 micron diameter particles.
SNRB catalytic baghouse laboratory pilot testing
Authors: Kudlac G. A. , Farthing G. A. , Szymanski T. , Corbett R. 
Published: February 2007

AbstractThe SOx‐NOx‐Rox BoxTM (SNRB) is an advanced air pollution process patented by Babcock & Wilcox (B&W) that provides for significantly reduced sulfur oxides (SOx), nitrogen oxides (NOx), and particulate emissions from coal‐fired boilers. The process uses a high‐temperature catalytic baghouse for integrating SOx reduction through injecting an alkali sorbent (such as hydrated lime or sodium bicarbonate), NOx removal through ammonia injection and selective catalytic reduction (SCR), and particulate collection. The advantages of the process include: compact integration of the emission control technologies into a single component; dry sorbent and by‐product handling; and improved SCR catalyst life due to lowered SOx and particulate levels.The SNRB concept has been successfully demonstrated in a 1500‐ACFM pilot baghouse at B&W's Alliance (Ohio) Research Center. This paper describes the SNRB technology and presents the SOx, NOx, and particulate removal performance results over a range of operating conditions for the laboratory pilot test program.
Evaluation of the TCE catalytic oxidation unit at Wurtsmith Air Force Base
Authors: Hylton T. D. 
Published: February 2007

AbstractWurtsmith Air Force Base is the site of an air‐stripping‐with‐emissions‐control system to remove volatile organic compounds (VOCs), chiefly trichloroethylene (TCE), from groundwater. The purpose of this study was to evaluate the performance of a fluidized‐bed catalytic oxidation unit for destroying halogenated organics with respect to catalyst bed temperature and operating time. The objectives included identification of any products of incomplete combustion formed and determination of the utility costs for the unit. Samples were collected over a period of ∼ 19 months with volatile organic sampling trains according to the Environmental Protection Agency (EPA) Method 30. Samples were taken at catalyst bed temperatures of 315, 370, 425, and 480°C. The results indicate that the incinerator was destroying the TCE with <97% efficiency when operated at ≥370°C. A conservative cost estimate for utilities was determined to be $0.36/1000 gal of water treated.
Pharmaceutical wastewater treatment comparison of process scale‐up from bench to full‐scale: A case study
Authors: Torrens Kevin D. , Musterman Jack L. , Drohobyczer Alexander 
Published: February 2007

AbstractWastewater treatability investigations were conduction for a specialty batch pharmaceuticals production facility which typically produces small quantities of numerous chemicals and pharamaceuticals. Production campaigns typically range from two days to four weeks in duration. Due to these production changes, the organic loading and chemical makeup of the wastewater constantly varies, resulting in less than optimum treatment plant performance. In addition, the facility planned to increase production in the future, thereby increasing wastewater flow and organic load.