bluuebunny/crossref_metadata_2025 huggingface dataset:
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

The 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

Chitosan, 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.
Modeling and simulation of bioremediation of contaminated soil
Authors: Wu J. C. , Fan L. T. , Erickson L. E.
Published: February 2007

A mathematical model has been developed for in situ biodegradation of contaminants in a soil bed. The model equations comprise three convection‐dispersion partial differential equations and one ordinary differential equation. Dimensional analysis of the model equations has been performed, and solution of these equations has been conducted by the newly‐developed three‐point backward finite difference method. The effects of insufficient oxygen supply, growth of biomass and resistance to contaminant migration on the rate of biodegradation have been examined by numerically simulating the dynamic behavior of in situ biodegradation processes. The results of numerical simulation indicate that the rate of biodegradation of contaminants in soil may be constrained not only by insufficient oxygen supply, but also by resistance to contaminant migration within the pore network. The effect of recycling the unreacted contaminants from the bottom of the bed to the top has been examined through simulation, showing that biodegradation takes place mainly in the upper part of the bed.
Design considerations and metals disposition in fluidized‐bed incineration of refinery wastes
Authors: Corry Robert G. , Rasmussen George P.
Published: February 2007

Disposal of refinery biotreatment sludges through land application is being strictly controlled and, in many cases, eliminated by regulatory constraint. An alternative to land application of sludges is incineration. This paper discusses fluidized‐bed incineration pilot studies conducted on refinery sludges obtained from two different refineries. Destruction of hazardous organic constituents, as well as the fate of inorganic metals, is discussed. Metal emissions are examined and the impact of the new EPA metals emissions limits is investigated. Installation of a waste heat recuperator to preheat combustion air is explored as an alternative to a high‐pressure sludge dewatering process.
Fluidized bed combustion of aluminum smelting waste
Authors: Tabery R. S. , Dangtran K.
Published: February 2007

Pilot tests by Fluidized Bed Combustion (FBC) have successfully destroyed Spent Potliner (SPL), a hazardous waste by‐product from aluminum smelters. Well known technical challenges such as ash agglomeration, ash leachate control, and off‐gas emission control have been studied and overcome by additives and by special combustion chamber design. Economic evaluation of a 20,000 tons per year (9 megawatt) facility indicates that disposal costs are competitive with land‐based disposal. A 0.5 MW Fluidized Bed Combustor of this design is under construction by Turnpoint Engineering Corporation.
Technical, economic, and regulatory evaluation of tray dryer solvent emission control alternatives
Authors: Li Ramon , Karell Marc
Published: February 2007

Public awareness and government agency attention have focused on emissions of organic compounds as a principal cause of the increased levels of ozone and smog in the ambient air across the nation. Evaporation of solvents from tray dryers, used in many applications in the chemical, pharmaceutical, and surface coating industries, potentially contributes significantly to the problem. Selecting and designing control equipment to comply with toughening solvent emission regulations is complicated by the needs to dilute the solvent concentration (for safety reasons) and by the emission profile which shows high initial emission rates declining over the drying cycle. There is no single control technology that will automatically satisfy all regulatory, economic and technical requirements. This article presents a comparison of several common control technologies applied to tray dryer solvent emissions based upon technical and economic considerations.
Performance models for NOx absorbers/strippers
Authors: Counce Robert M. , Crawford Douglas B. , Lucero Andrew J. , Sickles Joseph E.
Published: February 2007

The focus of this paper is to present a review of recent developments in the modeling of NOx absorbers and strippers. The fundamental concepts of design and process simulation for this specialized area of mass transfer are developed. This review and conceptual analysis is intended to provide simple design/simulation equations and to present the usefulnessand limitations of these equations. This activity is useful because of the interrelationships between mass transfer and the complexity of the NOxHNOxH2O chemical system.
An overview of solvent extraction treatment technologies
Authors: Hall Dorothy W. , Sandrin Joseph A. , McBride Rhonda E.
Published: February 2007

In the course of evaluating potential technologies for treatment of contaminated soils at a regulated site in the upper Midwest, solvent extraction technology was reviewd and appeared to be a viable alternative to incineration and land disposal. Because of stringent federal and state land disposal rules, liability issues, and rising disposal costs, technologies that will treat and detoxify hazardous wastes effectively are preferred over other less aggressive technologies. Industry is actively seeking and evaluating options, and the regulatory community is encouraging development and application of new treatment technologies as alternatives to land disposal. To advance this effort, the U.S. Environmental Protection Agency (EPA) established the Superfund Innovative Technology Evaluation (SITE) program to promote the development of innovative technologies and to demonstrate such technologies at Superfund sites. Solvent extration technology is being evaluated in the SITE program. This paper was prepared because of the lack of a compiled source of existing information on the alternative use of solvent extraction technology for treating soils contaminated with hazardous substances in a manner other than incineration.
Startup and opertion of an anaerobic biological activated carbon (AnBAC) process for treatment of a high strengh multicomponent inhibitory wastewater
Authors: Goeddertz John G. , Weber A. Scott , Ying Wei–chi
Published: February 2007

A joint study has been conducted by investigators at the State University of New York at Buffalo and Occidental Chemical Corporation to examine the feasibility of the anaerobic biologica activated carbon (AnBAC) process for treatment of a high strengh multicomponent inhibitory wastewater. The three principal components of the study waste are phenol, formaldehyde, and methanol. Bench–scale studies were conducted over a two‐year period using 2.54 cm and 5.08 cm ID AnBAC columns. Based on the results of the bench–scale studies, organic contaminant removal of greater than 90 percent was achived at loading rates of 0.06 g COD/g GAC/day.

Subsequently, the results from the bench–scale studies were used to design a pilot–scale AnBAC system which has been operating successfully for approximately ten months at Occidental Chemical Corporation's Durez Division plant in North Tonawanda, New York.

The purpose of this paper is to present performance data from both the bench– and pilot–scale systems and identify startup procedures found necessary for successful initiation of AnBAC column operation. Based on the data collected, the AnBAC process is capable of providing excellent treatment performance of the high strength waste. Proper balancing between the applied organic loading rate and the process removal capacity was found to be crucial in maintaining a healthy biomass during column startup due to the inhibitory nature of the wastewater.
Overview of industrial source control for nitrogen oxides
Authors: Rhoads T. W. , Marks J. R. , Siebert P. C.
Published: February 2007

Contemporary debate over major clean air issues has kept the control of nitrogen oxides (NOx) in the forefront of public interest. While amendments to the Clean Air Act, new rules, programs, and policies emerge in response to concern for acid deposition, ozone non–attainment, global warming, and public health and welfare, it is anticipated that NOx control technology will be applied to a greater degree. However, existing regulations, policy and market forces are already forcing technologicaladvances. This article presents a summary of the current regulatory situation and looks ahead at the Clean Air act reauthorization. The article also presents an overview of stationary source control for NOx emissions.
Groundwater treatment with zero air emissions
Authors: Cheuvront David A. , Giggy Christopher L. , Loven Carl G. , Swett Geoffrey H.
Published: February 2007

Air emissions from the treatment of volatile organic compound (VOC)–contaminated groundwater are a growing problem in the United States. Historically, air stripping has been used to remove VOCs from contaminated groundwater. Air stripping technology is a cross media treatment technique, i.e., it solves a groundwater problem by transferring contamination to the atmosphere.

In response to the air pollution problem created by air stripping, the public, air quality regulatory agencies, the federal government and private industry are exerting pressures to eliminate and/or reduce air emissions from the clean–up of contaminated groundwater. These forces make it desirable to consider alternative and innovative technologies for the treatment of groundwater contaminated with VOCs.
Biodegradation of chlorinated hydrocarbons in an immobilized bed reactor
Authors: Miller Gary P. , Portier Ralph J. , Hoover Darryl G. , Friday David D. , Sicard Jerry L.
Published: February 2007

A 75 liter immobilized microbe biological reactor with a bed retention time of 20.5 hours was used in a continuous flow mode to remediate contaminated groundwater containing ethylene dichloride (EDC), tetrachloroethylene, and trichloroethylene, with EDC being the predominant contaminant. The reactor was initially seeded with Xanthobacter autotrophicus, a demonstrated halogenated aliphatic substrate utilizer. The reactor was operated for forty‐two days. Material balance determinations for primary volatile aliphatics of concern indicated an average of 90.2% mineralization of EDC, 81.7% of the trichlorethylene (TCE) and 64.0% of the tetrachlorethylene (TeCE). In addition to Xanthobacter autotrophicus, four indigenous bacterial species from the groundwater had successfully acclimated to the reactor bed.
Innovative management of an Aerated/Facultative Lagoon suspended—growth biological treatment system for high strength industrial waste stabilization
Authors: Muirhead Timothy J.
Published: February 2007

Coors Bio Technology Products Company, in Johnstown, CO is a subsidiary company of Adolph Coors Brewery Company in Golden, CO. Coors BioTech is a corn wet–milling industrial plant which processes shelled corn and converts it into several basic economical products: high fructose corn syrup (HFCS), corn oils, starch, sugars, and various agricultural by–products (Figure 1). The corn wet–milling operation and HFCS refining process generates a continual discharge of numerous process wastes. This wastewater is characterized as being a high strength, soluble, biodegradable waste, highly variable in composition. Coors BioTech treats their own industrial waste on site at their wastewater treatment plant using the activated sludge process. The objective of this paper is to provide a more complete understanding of the necessity for innovative management of the Aerated/Facultative Lagoon in the Coors BioTech waste treatment process, and suggest the applications of such lagoons in secondary biological treatment systems for high strength industrial waste stabilization [1–5].
Supercritical fluid extraction of aromatic contaminants from a sandy loam soil
Authors: Andrews Arthur T. , Ahlert Robert C. , Kosson David S.
Published: February 2007

Near‐critical fluids and liquefied gases can achieve high efficiencies in the extraction of organic contaminants from soil. Adsorptive behavior of several polycyclic aromatic hydrocarbons (PAHs) from supercritical carbon dioxide (SC CO2) onto sandy loam‐type soil has been characterized. Data for the solubility of phenanthrene, anthracene, triphenylene, and perylene in SC CO2 demonstrates a strong relationship between solubility and the carbon number and angularity of the ring structure. Soil adsorption isotherms for these compounds are non‐linear, and have been described using Freundlich and BET adsorption models. The slope of the adsorption isotherms has been correlated with PAH solubility on log‐log coordinates. Addition of polar modifiers, e.g., water or methanol, dramatically reduces the PAH adsorption levels, indicating the importance of polar adsorption sites on soil surfaces.
Electrosorption: A case study on removal of dilute organics from water
Authors: Eisinger Ronald S. , Keller George E.
Published: February 2007

Electrosorption, or potential‐swing adsorption, appears well‐suited for recovery of dilute organic compounds from ionically conductive solutions.

The feasibility of using electrosorption in an industrially difficult separation, removal of ethyleneamines from a brine stream, is assessed here. The assessment included lab‐scale measurements using the model compound ethylenediamine, paper design of a commercial‐scale process, and economic evaluation. Separation is achieved by periodically swinging the electrochemical potential on an adsorbent to achieve cycles of adsorption and desorption. Adsorption of ethylenediamine on activated carbon increased threefold following a change in potential of 1 volt.

Adsorption increased at more negative potential, suggesting an acid/base‐type effect at the carbon surface. The key to scale‐up is use of relatively thin adsorbent beds to minimize time required to swing the potential. A design featuring stacked, 2‐cm‐thick layers of adsorbent separated by ion exchange membranes is proposed. The estimated cost of an electrosorption‐based process to reduce ethyleneamines concentration from 220 ppm to less than 60 ppm would be severalfold the value of recovered ethyleneamines.

However, when employed for environmental reasons, cleanup by electrosorption would be economically attractive relative to alternate separation techniques.
The use of pervaporation for the removal of organic contaminants from water
Authors: Lipski Chris , Cǒté Pierre
Published: February 2007

Pervaporation is an emerging polymeric membrane‐based process for the removal of organic compounds from water. A resistance‐in‐series model was formulated and validated using silicone rubber hollow fibers for the treatment of water containing trichloroethylene (TCE). This process model was coupled with a costing model to assist in the design of pervaporation systems. The model was used to predict performance, capital cost and operation cost of pervaporation for water treatment applications and to optimize design variables such as membrane thickness and the module hydrodynamics. Process characteristics and economics of pervaporation were compared to air stripping and activated carbon adsorption.
Treatment of organic‐contaminated wastewater streams by pervaporation
Authors: Wijmans J. G. , Kaschemekat J. , Davidson J. E. , Baker R. W.
Published: February 2007

The removal and recovery of organic contaminants from aqueous streams by pervaporation membrane systems is a viable and economical treatment for many waste streams. Specific opportunities for the technology are identified in this paper. Laboratory and pilot system data are used to develop system designs and to calculate the cost of treating specific streams.
Toxic trace pollutants from incineration
Authors: Siebert Paul C. , Alston Denise R. , Jones Kay H.
Published: February 2007

Toxic Trace Pollutant emission factors have been developed using a database of over 500 references, including 50 emission test reports for municipal solid waste (MSW) incineration. Procedures have been developed and computerized to calculate emission factors from the best available data for dioxin/furan toxic equivalents, carcinogenic PAHs, and other trace organics and metals. Statistical analyses have been performed on standardized test results to assess the relationship of emissions and various incineration and air pollution control equipment design and operating parameters. Although the data is much more limited for hazardous waste and medical waste incineration, the available data have been summarized.
Integrated model for predicting the fate of organics in wastewater treatment plants
Authors: Govind Rakesh , Lai Lei , Dobbs Richard
Published: February 2007

An integrated Fate Model has been developed for predicting the fate of organics in a wastewater treatment plant. The Fate Model has been validated using experimental data from a pilot‐scale facility. The biodegradation kinetic constants for some compounds in the Fate Model were estimated using the group contribution approach. The Fate Model has been compared with other existing models in the literature. Potential applications of the Fate Model include assessment of volatile organic compound (VOC) emissions from a wastewater treatment plant, evaluate pretreatment requirements prior to discharge to the sewer system, predict concentrations of toxic compounds on sludges, and provide a general framework for estimating the removal of toxic compounds during activated sludge treatment.
Application of selective catalytic reduction (SCR) technology for NOx reduction from refinery combustion sources
Authors: Cobb David , Glatch Lisa , Ruud John , Snyder Scott
Published: February 2007

Selective Catalytic Reduction (SCR) has been applied as a NOx abatement technique for stationary sources of nitrogen oxides (NOx) in Japan since the early 1970s. To date, there are over 100 SCR installations operating in Japan.

During the 1980s, a number of SCR systems have been installed in the United States, primarily in California. Among these applications are fired heater, boiler, and gas turbine/heat recovery steam generator (HRSG) installation. These installations provide a basis to assess the state‐of‐the‐art for applying SCR to comply with refinery NOx emission limitations.
Feasibility, modeling and economics of sequestering power plant CO2 emissions in the deep ocean
Authors: Herzog H. , Golomb D. , Zemba S.
Published: February 2007

The capture and disposal of carbon dioxide from the flue gas of fossil‐fueled power plants is technically feasible, albeit it requires a significant fraction of the energy content of the fossil fuel and additional equipment with large capital expenditures. The five processes investigated for capturing CO2 from the flue gas of coal‐fired power plants are (a) combustion of coal in an atmosphere of oxygen and recycled flue gas; (b) scrubbing the flue gas with a recyclable solvent (monoethanolamine); (c) cryogenic CO2 fractionation of the flue gas; (d) separation of CO2 by selective membrane diffusion; and (e) scrubbing of the flue gas with seawater. The captured CO2 is envisioned to be liquefied at 150 atm, piped to the deep ocean, and released through a diffuser. Model calculations show that with appropriate release conditions the formed CO2 drops can be completely dissolved in seawater. The process that requires least incremental energy is air separation/flue gas recycling. In this process about 30% of the total energy content of the coal is consumed, and the thermal efficiency of a power plant is reduced from 35% to about 25%. Excluding pipeline and deep water disposal costs, we estimate that electricity production costs will increase by about 80%.
The formation of inorganic particles during suspension heating of simulated wastes
Authors: Mulholland James A. , Sarofim Adel F. , Yue Guangxi
Published: February 2007

Measurements of metal partitioning between the fine condensation aerosol and the larger particles produced during rapid heating of aqueous and organic solutions containing metal additives with widely varying volatilities were made in a laboratory‐scale furnace operated over a range of temperatures (900 to 1500 K). A stream of monodisperse droplets (nominal diameter of 36 μm) was injected into an isothermal, laminar drop‐tube reactor, quickly developing into a stream of droplets with heterogeneous size distribution due to droplet collision and coalescence. Aqueous solutions containing nitrates of cadmium, lead and nickel gave rise to particles with trimodal size distributions. Partitoning of the larger particles between a residual mode (particle aerodynamic diameter, Dp,aero > 7 μm) and an intermediate mode (1 μm > Dp,aero > 7 μm) is suggestive of particle porosity variation. In addition, ultrafine particles, with submicron aerodynamic diameter, were formed, both by the anticipated vaporization pathway and by an unexpected explosive fragmentation mechanism. The higher volatility of the chloride than the oxide was evidenced by an enhanced inorganic aerosol formation during the high temperature treatment of a nickel chloride solution. The oxidative burning of organometallic solutions of nickel and lead produced only particles of submicron aerodynamic size.
Alternative waste minimization analyses for the printed circuit board industry: Examples for small and large manufacturers
Authors: Chang Li‐Yang , McCoy Benjamin J.
Published: February 2007

The objective of the present waste minimization study for printed circuit (PC) board manufacture is to evaluate solid/liquid separation technologies, engineering data, waste recycling processes, and cost economics to assess the feasibility of achieving significant reduction in the usage of water, the generation of wastewater, and hazardous waste. Two examples, for small and large manufacturers, demonstrate that an integrated waste minimization scheme can minimize waste by in‐process recycling, resource recovery, process modification, and automation. Economic analyses of these two examples shown that the integrated waste minimization scheme is more profitable that of the conventional sludge or the “zero sludge” schemes.
The evaluation of supplemental oxygen burner firing in a countercurrent rotary kiln
Authors: Acharya Prakash , Novak Rudy G.
Published: February 2007

Detailed tests were conducted to evaluate the process impact of treating contaminated soils by concurrently firing the Linde® Oxygen Combustion System (OCS) with the main kiln air‐natural gas burner. The evaluation was carried out at the Lousiana Army Ammunition Plant (LAAP) on explosives‐contaminated soil in International Technology's (IT) countercurrent kiln Hybrid Thermal Treatment System (HTTS®).

Cocurrent and countercurrent kiln firing positions (relative to soil flow) were utilized for the OCS at stoichiometric and substoichiometric oxygen ratios. The relative firing rates of the OCS and main burner were varied at a combined heat release of approximately 8.8 × 106W. A reference run was conducted to define process performance for the main kiln air‐natural gas burner alone. The feed soil contained 18 to 22 ppm nitroexplosives at an average moisture content of 17.5 percent (dry weight basis). A constant ash discharge temperature of approximately 480° C was maintained during the basic tests.

The average heat transferred to the soil feed for the reference case was 49 × 103W/m2 of kiln surface and for the OCS tests up to 55 × 103W/m2 was transferred. The average heat release for the reference run and the OCS tests was 160 × 103W/m3 and 187 × 103W/m3 respectively.

Capacity increases of up to 20 percent were achieved by firing the OCS in a countercurrent mode at a substoichiometric oxygen ratio of 56 percent, resulting in an operating cost reduction of about 12 percent. Higher oxygen stoichiometric ratios did not produce proportionally increased throughput.
Air assessment for land treatment no‐migration
Authors: Siegell J. H. , Madden P. C. , Chapman D. R.
Published: February 2007

Air pathway assessments for three landfarm sites were conducted for compliance with the no‐migration land disposal regulations. These assessments comprise of estimating the volatile and semi‐volatile emissions from sludge application using the CHEMDAT model and estimating particulate emissions during application and tilling using the Fugitive Particulate Matter Air Emissions Guidance. Ambient concentrations at the unit boundary were predicted using the ISC dispersion models. Ambient air monitoring during application and tilling was included as a check on the emission and dispersion models.
An at‐source treatment for organomercury‐containing hazardous liquid waste
Authors: Magliette R. J. , McKinney D. , Venkataramani E. S. , Bacher S. , Brian B.
Published: February 2007

An at‐source treatment has been developed for the removal of mercury from a spent fermentation waste to render it non‐hazardous. The organomercury‐containing fermentation wastewater is initially treated with aluminum metal power at pH 11.5 and ambient temperature to reduce the sulfur‐hydrogen bond to form mercury cations and organomercury fragments. Subsequent treatment with sodium borohydride reduces the mercury cations and organomercury fragments to elemental mercury. Ultrafiltration is then used to effectively remove the colloidal metallic mercury. Final polishing with granular activated carbon yields an effluent containing less than 10 μg/l mercury. The colloidal mercury present in the UF retentate as well as that bound to the granular activated carbon is amenable to reclamation and subsequent reuse. The at‐source treatment technology developed has been found to be capable of achieving a consistently high removal efficiency of 99.99%.
Biotreatment of hazardous organic wastes using rotating biological contactors
Authors: Tokuz R. Yucel
Published: February 2007

Treatment of several toxic organic compounds in Rotating Biological Contactor (RBC) units was examined in this study. The following compounds were included: 2‐Chlorophenol; 2,4‐dichlorophenol; 2,4,6‐trichlorophenol; pentachlorophenol; 2‐nitrophenol; diethyl phthalate and di‐n‐butyl phthalate.
Application of amines for treating flue gas from coal‐fired power plants
Authors: Kwong K. Vincent , Meissner Iii Ronald E. , , Ahmed Saif , Wendt Carl J.
Published: February 2007

Some of the earliest applications of amines for treating flue gas were to recover carbon dioxide for dry ice production and beverage carbonation. The amine process was later applied to recover CO2 for urea production. In the late 1970's and early 1980's during the period of major enhanced oil recovery projects, amines were used to recoverCO2 from flue gas for injection. In those plants, SO2 was typically removed by an alkaline scrubbing system upsteam of the amine process, but nothing was done to reduce the NOx and excess oxygen in the flue gas. Residual SO2, NOx, and oxygen caused amine degradation and in some cases led to severe corrosion.

Recent advances have been made in hydrotreating of power plant boiler flue gases to reduce SOx and NOx, the major components of acid rain, to hydrogen sulfide and nitrogen, and to convert excess oxygen to water. The sulfur pollutants in the form of H2S can be recovered and converted to elemental sulfur by a selective amine unit and a Recycle Selectox sulfur recovery unit. This combination of units, the Parsons Flue Gas Cleanup (FGC) Process, shows great promise in abating the SOx and NOx pollutants from coal‐fired power plants and provides a novel use for selective amines.

This paper reviews some of the earlier applications of amine in flue gas treating and the recent development of the parsons FGC process for over 99 percent removal of both SOx and NOx.
Regeneration of waste chemicals from liquid redox processes
Authors: Ciriacks John A. , Lafond James F.
Published: February 2007

To avoid the increasingly costly disposal of the waste stream (blowdown) from liquid redox processes used to clean hydrogen sulfide from gases, a reductive burning recovery (RBR) process has been developed. Its initial installation has recently been completed at Dofasco Steel Inc., Hamilton, Ontario, in order to treat the effluent from two Stretford liquid redox systems.

The RBR system concentrates spent Stretford chemicals which are primarily sodium thiosulfate and sodiuim sulfate. The spent chemicals are then thermally destroyed in a reactor. The regenerated salts flow from the bottom of the reactor as a molten smelt containing sodium carbonate, sodium sulfide and sodium vanadate.

The molten salt stream is dissolved in water to form a regenerated solution which is fed back into the Stretford process. For the special case of coke oven gas cleaning, elemental sulfur is added to a portion of the regnerated solution in order to clean hydrogen cyanide from the coke gas before the gas is scrubbed with Stretford solution to remove hydrogen sulfide. The sodium thiocyanate product of hydrogen cyanide scrubbing is also thermally destroyed and regenerated by the RBR process.

RBR Technology essentially closes the Stretford process for cleaning coke oven and other industrial gases. Only a small amount of ash which has been filtered from the regenerated chemicals needs disposal.
NOx/CO emissions and control in ethylene plants
Authors: Gomaa Hassan M. , Hackemesser Larry G. , Cindric David T.
Published: February 2007

The principal emission source of nitrogen oxides (NOx) and carbon monoxide (CO) from ethylene plants is the pyrolysis furnace. This paper addresses NOx/CO emissions and controls for gas fired pyrolysis furnaces. Typical NOx and CO generation rates for furnaces are quantified. The impact of fuel coposition on NOx generation is discussed. Commercially available and emerging control technologies are reviewed. The relative costs of these controls are compared. Case‐by‐case considerations will dictate the selection of the control technology required to comply with the environmental demands of the specific site.
Preliminary studies on the granular activated carbon‐sequencing batch biofilm reactor
Authors: Chozick R. , Irvine R. L.
Published: February 2007

The Granular Activated Carbon‐Sequencing Batch Biofilm Reactor (GAC‐SBBR), a system which combines a submerged membrance oxygenation system to support a biofilm with granular activated carbon (GAC), and the Sequencing Batch Biofilm Reactor (SBBR), a comparable system containing no GAC, were investigated to determine the efficiency of each for the treatment of wastewaters containing volatile components. Toluene, at feed concentrations between 100 and 200 mg/L, was reduced to less than 10 μg/L in both systems. In the GAC‐SBBR, biodegradation and adsorption were responsible for 92% and 8%, respectively, of the toluene removal, while in the SBBR, all of the toluene was removed by biodegradation. The quantity of toluene volatilized from the GAC‐SBBR over a 10 week period of operation was approximately 0.003% of the toluene introduced. The major consideration for long‐term, efficient operation of these systems is selection of an operating strategy which results in the supply of sufficient oxygen to the biomass. Both biomass wasting and purging of the membrane oxygenation system were critical for maintaining adequate oxygen transfer to the biofilm in the GAC‐SBBR and in the SBBR.
Control of aromatic waste air streams by soil bioreactors
Authors: Miller Dennis E. , Canter Larry W.
Published: February 2007

Three soils were examined for the ability to degrade hydrocarbon vapors of benzene, toluene, ethylbenzene, and o‐xylene (BTEX). Each of these compounds are major aromatic constituents of gasolines. The soils examined were Rubicon Sand from Traverse City, Michigan, Durant Loam from Ada, Oklahoma, and Dougherty Sand from Stratford, Oklahoma. Soil columns were used to examine the effects of soil type, air flow rate and inlet vapor concentrations. Adjustment of the hydrocarbon loading rate produced removals which corresponded to first‐order removal kinetics. Estimated residence times of 10 to 20 minutes produced removals of the individual inlet BTEX compounds which ranged from 8 to 39%. Increasing the residence time produced increased removals corresponding to first‐order removal rates. Further increases in the residence time revealed transport limitations which restricted additional removals. Soil which had moisture less than 50% of saturation displayed preferential utilization of benzene followed in order by ethylbenzene, toluene, and o‐xylene.
The reuse of petroleum and petrochemical waste in cement kilns
Authors: Gossman David
Published: February 2007

The high temperatures and long residence times in the combustion zones of cement kilns have been used for over ten years to burn flammable liquid hazardous wastes, such as solvents, as fuels. Increasing government regulation and control of this technology has actually resulted in expanded use as both waste generators and cement manufacturers have grown more comfortable and confident of this technology. Liquid petroleum and petrochemical wastes have been a part of this liquid fuel stream from its inception. Solid and sludgy petroleum and petrochemical wastes present greater handling difficulties. Nevertheless, the land ban of many of these hazardous wastes has resulted in the motivation to develop solid and sludge handling and processing technologies to allow their use as fuel. These processing options extend back to the point of generation. Changes in filter press media and drying technologies are allowing certain petroleum and petrochemical wastes to be pneumatically introduced into cement kilns. Quality control technologies, including laboratories at both cement kilns and the generating/processing location, have also been a critical part of these developments. As this technology matures, as much as 454,000,000 kg of nationwide capacity for hazardous waste fuel solids is likely to become available.
Combined SO2 and NOx removal by means of dry sorbent injection
Authors: Helfritch Dennis , Bortz Steven , Beittel Roderick , Bergman Perry , Toole‐O'Neil Barbara
Published: February 2007

The team of Research‐Cottrell and Riley Stoker is conducting a proof‐of‐concept demonstration of an Integrated Dry Injection process for coal‐fired boiler SO2 and NOx control under a U.S. Department of Energy contract with co‐funding by the Electric Power Research Institute. The SO2 and NOx removal technologies, which are combined in this demonstration test, have been independently evaluated but have not yet been tested as an integrated system. The integrated tests are important to determine and characterize any interactions between the technologies, either positive or negative.

Subscale tests were conducted to determine the best calcium and sodium sorbents to use in the proof‐of‐concept demonstration. The demonstration is being conducted on the large combustor at the Riley Stoker Research Facility. The parametric test program consists of a series of tests for the purpose of demonstrating SO2 and NOx reductions and is designed to allow a determination of the influence of each parameter on SO2 and NOx removal.
Air stripping VOCs from groundwater: Process design considerations
Authors: Ball Brandon R. , Edwards Michael D.
Published: February 2007

Considerations for evaluating and designing the air stripping process are presented by case study. The case study involves the design of an air stripping process to remediate groundwater contaminated with volatile organic compounds (VOCs) at a National Priorities List site in Tacoma, WA. Design objectives included developing a tower with minimum volume and energy requirements while complying with discharge air and water quality standards. A two‐phase resistance model using Onda correlations to determine liquid‐ and gas‐phase resistance model using Onda correlations to determine liquid‐ and gas‐phase mass transfer coefficients was used to assist in the evaluation and design.

Considerations for applying the two‐phase resistance model to air stripping tower design are presented. The ability of the model to simulate process performance is demonstrated by comparison with actual data for 11 priority pollutant list VOCs evaluated during an onsite pilot study. Design procedures with which to develop a tower with minimum volume and energy requirements are described. Other considerations involving the evaluation of VOC emissions and the precipitation and buildup of inorganic constituents within the internal packing media are described.
LBL PhoSNOX process for combined removal of SO2 and NOx from flue gas
Authors: Chang S. G. , Lee G. C.
Published: February 2007

The addition of yellow phosphorus in wet scrubbing systems can result in the high efficiency simultaneous removal of SO2 and NOx from flue gas. Yellow phosphorus reacts with O2 to produce O3 which selectively oxidizes NO to NO2. Subsequently, NO2 and SO2 are removed from flue gas by dissolution into an aqueous alkaline solution/slurry, where they are converted to ammonium sulfate and gypsum. Yellow phosphorus is oxidized to yield a desirable commercial by‐product, phosphoric acid.

This new technology has been tested jointly by LBL and Bechtel at LBL with a 20 cfm [9.44 × 10−3 m3 / sec] bench‐scale scrubbing absorber. The test results indicated that greater than 90% NO removal efficiency could be achieved with an L/G>60 (gal/min)/(1000 cu ft/min) [1 liter/m3 = 7.48 gal/1000 cu ft] for NO concentrations ranging from 60 to 600 ppm. A stoichiometric ratio, P/NO, as low as 0.6 has been achieved. Economic projections for the PhoSNOX process have been made based on a conceptual process configuration. The estimated costs compare favorably with the SCR for high removal and are competitive with urea injection processes for low levels of NOx removal. FMC has conducted a safety study of the process and concluded that the potential safety hazards of yellow phosphorus can be avoided if proper precautions are taken.
Application of electro acoustics for dewatering pharmaceutical sludge
Authors: Golla Padma S. , Johnson Harold W. , Senthilnathan P. R.
Published: February 2007

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.
Use of risk assessment groundwater model in installation restoration program (IRP) site decisions
Authors: Goldblum David K. , Clegg John M. , Erving John D.
Published: February 2007

Toxic chemicals have created much public concern over the past thirty years due to both environmental pollution and hazardous waste management. Hence, the associated Risk Assessment Process is both complicated and crucial in the outcome of decisions concerning remediation. Quantification for a particular contaminant can demonstrate that the concentration is adequately low, so that there is no need to carry out a remedial action, at that given site. The contaminant's specific calculated risk in a risk assessment is directly proportional to the average concentration of that contaminant chemical. The total risk is additive for all the contaminants present at that site, for both carcinogenic and non‐carcinogenic risks. Further analysis into the risk assessment for a drum storage area at a DOD installation rendering airlift support for airborne forces resulted in elimination of an unnecessary and costly remedial action.
Kinetics of sulfer dioxide uptake on supported cerium oxide sorbents
Authors: Hedges Sheila W. , Yeh James T.
Published: February 2007

A thermogravimetric technique has been used to evaluate the apparent rate of SO2absorption by ceria supported on alumina. A kinetic model for the sulfation of the CeO2/Al2O3sorbent has been developed that is first order with respect to the partial pressure of SO2and first order with respect to the fractional unreacted cerium oxide on the sorbent. The reaction was also found to be zero order with respect to the oxygen and water vapor content of the gas over a range of concentrations that might reasonably be encountered in actual flue gas streams. CeO2/Al2O3sorbent is being studied at the Pittsburgh Energy Technology Center as a potential new sorbent for simultaneous removal of 90+% of both SO2and NOxfrom coal combustion flue gas in a dry, regenerable process.
Treatment and stabilization of a hexavalent chromium containing waste material
Authors: Jacobs Jerome H.
Published: February 2007

In order to stabilize such wastes, it is necessary to convert the Cr+6 to the trivalent (Cr+3) form, before solidifying the waste through the use of cementitious materials such as portland cement or pozzolime (cement kiln dust). A treatment scheme was developed using ferrous ammonium sulfate (FAS) as reducing agent. With FAS the reaction kinetics are sufficiently rapid at neutral or alkaline pH ranges. With most other reducing agents, such as sodium metabisulfite or ferrous sulfate, it would first be necessary to adjust the pH to about 2 S.U. in order for the reduction reaction to proceed in reasonable time. Bench scale tests were conducted in which the waste material containing about 6,000 mg/kg of Cr+6 and with pH approximately II S.U., was reacted with varying doses of FAS at pH levels of 4.5, 7, and as received. The reaction was found to be essentially complete after 3 days and selective for Cr+6. Further tests were conducted in which pozzolime was added to the mixture after the reduction. With an approximately 1:1 ratio of FAS: waste and pozzolime ratios of between 0.5:1 and 1:1, residual hexavalent chromium and total chromium concentrations were well below 100 mg/kg of waste, which corresponds to the EP Toxicity limit of 5 mg/L. The costs for full‐scale FAS/pozzolime stabilization were estimated. Testing of alternative reducing agents, which would require first acidifying with sulfuric acid, was deemed not warranted. The acid quantities required would be costly, and such operations in field conditions were felt to be not prudent.
Formation of NOx by digestion of phosphate ores with concentrated nitric acid
Authors: Tinge Ir. J. T.
Published: February 2007

The digestion of twelve phosphate ores with concentrated nitric acid has been studied in order to quantify the formation of nitrogen oxides, NOx. The experiments were performed in a batch laboratory‐scale reactor under reaction conditions which are representative of the acidulation of phosphate rock with nitric acid in the nitrophosphate process, an important process for the production of compound fertilizers. The results obtained from these experiments show that the amount of NOx formed during digestion is directly proportional to the organic carbon content and is only marginally related to the carbonate and fluoride contents of these phosphate ores. It is assumed that organic material in the ores is partly oxidized by nitric acid, which in its turn is reduced to NO and NO2. On the basis of our results the following correlation between the organic carbon content and the quantity of nitrogen produced in the form of nitrogen oxides is proposed: [NOx‐N] = A. [Corg] in which A = 0.65 if [NOx‐N] and [Corg] are both expressed on a weight basis and A = 46 if [NOx‐N] and [Corg] are expressed in mol/tonne of P2O5 and kg/tonne of P2O5, respectively. The result is important in specifying the value of phosphate ores for the nitrophosphate process because it quantifies the possible emissions of NOx into the atmosphere as well as the amount of wasted nitric acid.
Ultrasonic destruction of chlorinated compounds in aqueous solution
Authors: Wu Jiann M. , Huang H. S. , Livengood C. D.
Published: February 2007

The application of ultrasonic‐wave energy for the destruction of low concentrations of carbon tetrachloride into nonhazardous end products is described, and the results of experimental work are presented. Process parameters studied included steady‐state temperature, concentration, pH, irradiation time, and the intensity of the applied ultrasonic‐wave energy. Greater than 99% destruction efficiencies were achieved through this process, and the irradiation time required for a given degree of destruction decreased with increasing intensity of the ultrasonic energy. In addition, a detailed chemical reaction mechanism for the destruction of carbon tetrachloride in water was formulated. The agreement between the model and experimental results is generally good.
Effect of chemical pretreatment on anaerobic biodegradation of refractory organic compounds
Authors: Wang Yi‐Tin
Published: February 2007

The potential for using chemical oxidation to enhance anaerobic biodegradability and reduce toxicity of two model phenolic compounds (o‐cresol and 2,4‐DNP) was evaluated. Batch bioassays were performed on the model compounds and their oxidation samples to determine biodegradability and toxicity in batch methanogenic cultures. Ozone, hydrogen peroxide, and potassium permanganate were the three oxidants examined in this study. A dose of approximately 5 moles hydrogen peroxide, in the presence of a ferrous iron catalyst (Fenton's reagent), 7 moles permanganate, or 25 moles of ozone per mole of o‐cresol was needed to significantly enhance anaerobic biodegradability of oxidation samples. Approximately 2.5‐4.5 moles of hydrogen peroxide or 7 moles of ozone per mole of 2,4‐DNP reduced methanogenic toxicity by 50%.