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Test of a magnetic device for the amelioration of scale formation at Treatment Facility D

Description: A commercial device (Descal-A-Matic{reg_sign}, Norfolk, VA) designed to treat water by means of a magnetic field has been evaluated for its effect on the formation of calcite scale at LLNL Treatment Facility D. At this facility, volatile organic contaminants (VOCs) are removed by air stripping, which raises the water pH, causing the deposition of calcium carbonate as calcite scale downstream. To evaluate the magnetic treatment technique, the ground water was passed through the Descal-A-Matic{reg_sign} device before treatment by the air stripping unit, and the resulting scale formation and other water characteristics were compared with those found during a test with no water treatment and a test with chemical treatment with a polyphosphate additive. No beneficial effect was found when using the magnetic device. 6 refs., 6 figs., 4 tabs.
Date: December 1, 1996
Creator: Krauter, P.W., Harrar, J.E., Orloff, S.P., Bahowick, S.M. & Bahowick, S. M.
Partner: UNT Libraries Government Documents Department

HEPA filter jointer

Description: A HEPA filter jointer system was created to remove nitrate contaminated wood from the wooden frames of HEPA filters that are stored at the Rocky Flats Plant. A commercial jointer was chosen to remove the nitrated wood. The chips from the wood removal process are in the right form for caustic washing. The jointer was automated for safety and ease of operation. The HEPA filters are prepared for jointing by countersinking the nails with a modified air hammer. The equipment, computer program, and tests are described in this report.
Date: February 1, 1998
Creator: Hill, D. & Martinez, H.E.
Partner: UNT Libraries Government Documents Department

Corrosion in coal-fired boilers

Description: The corrosive effect of the flue gas and the fly ash from burning coal on combustion and pollution control equipment has led to extensive research efforts aimed at solving this problem. A wide variety of chemical additives are offered by suppliers to perform corrosion reduction functions when added to the solid or liquid fuel. Protection of equipment by the use of corrosion resistant coatings and improved designs to prevent or reduce slag formation are also well known corrosion reduction techniques. However, the problem facing management is to evaluate the many different alternatives and to define the most effective one for their particular facility. Information gained from previous corrosion reduction attempts, and knowledge of factors which increase the SO/sub 3//SO/sub 2/ ratio in the flue gas have resulted in the investigation of methods of controlling the dew point and therefore, reducing the condensation of sulfuric acid. Various methods of avoiding the formation of acid are being evaluated.
Date: January 1, 1982
Creator: Vausher, A.L.
Partner: UNT Libraries Government Documents Department

Feasibility study on the use of a rotating fluidized bed as a dust filter

Description: A brief survey was made of the characteristics of the rotating fluidized bed used as a filter for fine dusts and mists. A sample calculation of overall filtration efficiency was made for a rotating bed operating at minimum fluidization with a velocity of 4 m/sec and a g-loading of about 50. Account was taken of removal by the classical mechanisms of diffusion, interception, and inertial impaction. High efficiencies were found for dust particles as small as 1 ..mu..m. The rotating fluid bed filter should have approximately the same collection efficiency and pressure drop as the fixed and moving bed filters operating at the same velocity, but in addition should more readily permit continuous operation without clogging and with effective regeneration. The same sample calculation of filtration efficiency applied to the conventional 1-g fluid bed operating at 1.5 times the minimum fluidization velocity of 0.2 m/sec indicated lower collection efficiencies near 1 ..mu..m than for the rotating system. The low velocity - and corresponding low throughput - in the stationary system is required to avoid bubble formation which would tend to lower filtration efficiency because of bypassing. The possible harmful effect on filtration efficiency of reentrainment of dust particles at the high operating velocities of the rotating system as well as the helpful effect of triboelectrification will have to be determined by experiment.
Date: September 1, 1978
Creator: Pfeffer, R & Hill, F B
Partner: UNT Libraries Government Documents Department

Technology demonstration for reducing mercury emissions from small-scale gold refining facilities.

Description: Gold that is brought from artisanal and small-scale gold mining areas to gold shops for processing and sale typically contains 5-40% mercury. The uncontrolled removal of the residual mercury in gold shops by using high-temperature evaporation can be a significant source of mercury emissions in urban areas where the shops are located. Emissions from gold shop hoods during a burn can exceed 1,000 mg/m{sup 3}. Because the saturation concentration of mercury vapor at operating temperatures at the hood exhaust is less than 100 mg/m{sup 3}, the dominant component of the exhaust is in the form of aerosol or liquid particles. The U.S. Environmental Protection Agency (EPA), with technical support from Argonne National Laboratory (Argonne), has completed a project to design and test a technology to remove the dominant aerosol component in the emissions from gold shops. The objective was to demonstrate a technology that could be manufactured at low cost and by using locally available materials and manufacturing capabilities. Six prototypes designed by Argonne were locally manufactured, installed, and tested in gold shops in Itaituba and Creporizao, Brazil. The initial prototype design incorporated a pebble bed as the media for collecting the mercury aerosols, and a mercury collection efficiency of over 90% was demonstrated. Though achieving high efficiencies, the initial prototype was determined to have practical disadvantages such as excessive weight, a somewhat complex construction, and high costs (>US$1,000). To further simplify the construction, operation, and associated costs, a second prototype design was developed in which the pebble bed was replaced with slotted steel baffle plates. The system was designed to have flexibility for installation in various hood configurations. The second prototype with the baffle plate design was installed and tested in several different hood/exhaust systems to determine the optimal installation configuration. The significance of coagulation and collection of the ...
Date: June 30, 2008
Creator: Habegger, L. J.; Fernandez, L. E.; Engle, M.; Bailey, J. L.; Peterson, D. P.; MacDonell, M. M. et al.
Partner: UNT Libraries Government Documents Department

The Homogeneous Forcing of Mercury Oxidation to Provide Low-Cost Capture

Description: Oxidized mercury formed in combustors (e.g., HgCl{sub 2}) is much more easily captured in existing pollution control equipment (e.g., wet scrubbers for SO{sub 2}) than elemental mercury. This is principally due to the high solubility of the oxidized form in water. Work over the last several years in our laboratory and elsewhere has identified the general outlines of the homogeneous chemistry of oxidation. The goal of the work reported here is to make use of this knowledge of the oxidation mechanism to devise simple and inexpensive ways to promote the oxidation. The hypothesis is that simple fuels such as hydrogen or CO can promote oxidation via the free radicals they generate during their decomposition. These free radicals then promote the formation of Cl from HCl via reactions such as OH+HCl {yields} H{sub 2}O+Cl. The Cl (and Cl{sub 2} derived from Cl recombination) are considered the principal oxidizing species. In our studies, mercury vapor is exposed to HCl under isothermal conditions in a gas containing N{sub 2}, O{sub 2}, and H{sub 2}O. The experiments systematically explore the influence of reaction temperature, HCl concentration, and H{sub 2}O concentration. These baseline conditions are then perturbed by the addition of varying amounts of H{sub 2}, CO, and H{sub 2}/CO added jointly. The following report presents the results of a literature review associated with the dissertation of the student supported by the program. This outlines the state-of-the-art in mercury behavior. It then describes the experimental facilities and the results of tests involving the promotion of the oxidation reaction by H{sub 2}, CO, and H{sub 2}/CO combinations. These results indicate a substantial enhancement of oxidation under isothermal conditions at 900-1000 K, while the additives inhibit oxidation at 1200 K. The next step is to determine whether the existing chemical kinetic models of mercury oxidation are capable ...
Date: April 1, 2006
Creator: Kramlich, John C. & Castiglone, Linda
Partner: UNT Libraries Government Documents Department

Evaluation of microporous carbon filters as catalysts for ozone decomposition

Description: Ozone is produced in small quantities in photocopiers and laser printers in the workplace and large quantities in industrial waste water treatment facilities. Carbon filters are commonly used to decompose this unwanted ozone. The three most important factors in producing a filter for this purpose are flow properties, efficiency, and cost. Most ozone decomposition applications require very low back-pressure at modest flow rates. The tradeoff between the number of pores and the size of the pores will be discussed. Typical unfiltered emissions in the workplace are approximately 1 ppm. The maximum permissible exposure limit, PEL, for worker exposure to ozone is 0.1 ppm over 8 hours. Several methods have been examined to increase the efficiency of ozone decomposition. Carbon surfaces were modified with catalysts, the surface activated, and the surface area was increased, in attempts to decompose ozone more effectively. Methods to reduce both the processing and raw material costs were investigated. Several sources of microporous carbon were investigated as ozone decomposition catalysts. Cheaper processing routes including macropore templating, faster drying and extracting methods were also studied.
Date: December 31, 1994
Creator: Whinnery, L.; Coutts, D.; Shen, C.; Adams, R.; Quintana, C. & Showalter, S.
Partner: UNT Libraries Government Documents Department

Mercury speciation measurements on a 10 MW{sub e} coal-fired boiler simulator

Description: The current trends towards deregulation of electric utilities, air toxic regulations and stringent fine particulate emissions reflect an increased need for coal-based research. In response, Babcock and Wilcox invested in the state-of-the-art 100 million Btu/hr (10 MW, equivalent) Clean Environment Development Facility (CEDF) located in Alliance, Ohio. The representative combustion conditions, flow patterns and residence times permit direct scale-up of CEDF test results to commercial boilers and pollution control devices. In cooperation with the U.S. Department of Energy and the Ohio Coal Development Office within the Ohio Office of Development, B&W is employing the CEDF to conduct a five-year project aimed at the development of practical, cost-effective strategies for reducing the emissions of hazardous air pollutants from coal-fired boilers. The project specifically targets the control of mercury, the trace element under close scrutiny by the EPA. Due to the various forms of mercury emissions from coal-fired boilers, accurate mercury speciation measurements are required to develop mercury control strategies. Current uncertainty in the accuracy and mercury speciation capability of mercury sampling methods led B&W to use both EPA Method 29 and the Ontario Hydro procedures to measure mercury emissions from CEDF pollution control devices. A comparison of the speciated mercury emissions is presented.
Date: June 1, 1997
Creator: Evans, A.P. & Nevitt, K.D.
Partner: UNT Libraries Government Documents Department

Radical oxidation automotive de-NO{sub x}

Description: The authors describe an experiment to remove NO{sub x} from air-like gas flows by optimizing its oxidation to nitric acid. Their aim is to demonstrate an efficient de-NO{sub x} process that can replace the catalytic converter of today`s automobiles and recover greater engine performance. NO is oxidized to HNO{sub 3} by injecting O{sub 3} from an auxiliary air discharge unit, and the acid is scrubbed by a granular NaOH filter, the final product being NaNO{sub 3}. In theory this scheme requires less engine power than the enthalpy loss through the catalytic converter, and permits engine operation with oxygen-rich fuel mixtures at high compression ratios for peak thermodynamic efficiency. Experiments utilize a glass tube flow reactor with a 20 liter/minute flow mixed from the separate injections of compressed ozonized air and an admixture of 200 ppm of NO in nitrogen from a small pressurized bottle, for net proportions of 89% N{sub 2}, 11% O{sub 2}, 120 ppm NO. Ozone concentration is selected by adjusting the frequency of the repetitive-pulsed coaxial-barrier air discharge cell. For O{sub 3}:NO ratios greater than unity a chain of reactions successively produce NO{sub 2}, NO{sub 3}, and N{sub 2}O{sub 5} which then combines with ambient H{sub 2}O to form HNO{sub 3}. The overall efficiency is dominated by the electrical efficiency of the ozonizer, at present about 30 eV/O{sub 3} within the discharge.
Date: May 1, 1995
Creator: Chang, B. & Garcia, M.
Partner: UNT Libraries Government Documents Department

PARTICULATE EMISSION ABATEMENT FOR KRAKOW BOILERHOUSES

Description: A U.S./Polish Bilateral Steering Committee (BSC) and the Department of Energy (DOE) selected LSR Technologies, Inc. as a contractor to participate in the Krakow Clean Fuels and Energy Efficiency Program. The objective of this program was the formation of business ventures between U.S. and Polish firms to provide equipment and services to reduce air emissions in the city of Krakow. A cooperative agreement was entered into by DOE and LSR to begin work in April 1994 involving implementation of particulate control technology called a Core Separator{trademark} for coal-fueled boilerhouses in the city. The major work tasks included: (1) conducting a market analysis, (2) completion of a formal marketing plan, (3) obtaining patent protection within Poland, (4) selecting a manufacturing partner, and (5) completing a demonstration unit and commercial installations. In addition to work performed by LSR Technologies, key contributors to this project were (1) the Polish Foundation for Energy Efficiency (FEWE), a non-profit consulting organization specializing in energy and environmental-related technologies, and (2) EcoInstal, a privately held Polish company serving the air pollution control market. As the project concluded in late 1998, five (5) Core Separator{trademark} installations had been implemented in the city of Krakow, while about 40 others were completed in other regions of Poland.
Date: September 30, 1998
Creator: Easom, Bruce H.; Leo A, Smolensky; Wysk, S. Ronald; Surowka, Jan; Litke, Miroslaw & Ginter, Jacek
Partner: UNT Libraries Government Documents Department

MEMBRANE SYSTEM FOR RECOVERY OF VOLATILE ORGANIC COMPOUNDS FROM REMEDIATION OFF-GASES

Description: In situ vacuum extraction, air or steam sparging, and vitrification are widely used methods of remediating soil contaminated with volatile organic compounds (VOCs). All of these processes produce a VOC.-laden air stream from which the VOC must be removed before the air can be discharged or recycled to the generating process. Treatment of these off-gases is often a major portion of the cost of the remediation project. Carbon adsorption and catalytic incineration, the most common methods of treating these gas streams, suffer from significant drawbacks. Membrane Technology and Research, Inc. (NITR) proposes an alternative treatment technology, based on permselective membranes that separate the organic components from the gas stream, producing a VOC-free air stream. The technology we propose to develop can be applied to all of these off-gas streams and is not tied to a particular off-gas generating source. We propose to develop a completely self-contained system because remediation projects are frequently in remote locations where access to trained operators and utilities is limited. The system will be a turnkey unit, skid-mounted and completely automatic, requiring power but no other utilities. The system will process the off-gas, producing a concentrated liquid VOC stream and a purified gas containing less than 10 ppm VOC that can be discharged or recycled to the gas-generating process.
Date: January 13, 2000
Creator: Wijmans, J.G.; Daniels, R. & Olsen, R.
Partner: UNT Libraries Government Documents Department

Estimation of mass transfer and kinetics in operating biofilters for removal of VOCs

Description: Long-term, stable operation of trickle-bed bioreactors remains desirable, but is difficult to achieve for industrial processes, which generate continuous streams of dilute gaseous hydrocarbons. Mass transfer and kinetic parameters are difficult to measure, complicating predictive estimates. Two methods are presented which were used to predict the importance of mass transfer versus kinetics limitations in operating trickle-bed biofilters. Both methods altered the overall kinetic activity of the biofilter and estimated the effective mass transfer coefficient (K{sub 1}a) by varying the VOC (volatile organic contaminant) loading rate and concentration. The first method, used with developing biofilters possessing low biomass, involved addition of cultured biomass to the recirculating liquid to effect an overall change in VOC removal capacity. The second method altered the total bed temperature of a well-established biofilter to effect a change. Results and modeling from these experiments are presented for a mixed culture biofilter which is capable of consuming sparingly soluble alkanes, such as pentane and isobutane. Methods to control overgrowth are discussed which were used to operate one reactor continuously for over 24 months with sustained degradation of VOC alkanes with a rate of 50 g/h/m{sup 3}.
Date: November 18, 1997
Creator: Barton, J.W.; Davison, B.H. & Gable, C.C.
Partner: UNT Libraries Government Documents Department

First report on non-thermal plasma reactor scaling criteria and optimization models

Description: The purpose of SERDP project CP-1038 is to evaluate and develop non-thermal plasma (NTP) reactor technology for Department of Defense (DoD) air emissions control applications. The primary focus is on oxides of nitrogen (NO{sub x}) and a secondary focus on hazardous air pollutants (HAPs), especially volatile organic compounds (VOCs). Example NO{sub x} sources are jet engine test cells (JETCs) and diesel engine powered electrical generators. Example VOCs are organic solvents used in painting, paint stripping, and parts cleaning. To design and build NTP reactors that are optimized for particular DoD applications, one must understand the basic decomposition chemistry of the target compound(s) and how the decomposition of a particular chemical species depends on the air emissions stream parameters and the reactor operating parameters. This report is intended to serve as an overview of the subject of reactor scaling and optimization and will discuss the basic decomposition chemistry of nitric oxide (NO) and two representative VOCs, trichloroethylene and carbon tetrachloride, and the connection between the basic plasma chemistry, the target species properties, and the reactor operating parameters (in particular, the operating plasma energy density). System architecture, that is how NTP reactors can be combined or ganged to achieve higher capacity, will also be briefly discussed.
Date: January 13, 1998
Creator: Rosocha, L.A. & Korzekwa, R.A.
Partner: UNT Libraries Government Documents Department

Compact de-NOxer for automotive exhaust

Description: Our two year project concluded with mixed results. The basic idea of using ozone and hydroxyl radical in a two stage plasma chemical reactor to remove NO{sub x} from automotive exhaust proved to be correct. However we found the energy needed to operate the plasma chemical reactor is 30% of the engine`s output, which is three times larger than that of the conventional catalytic converter. Our project is a partial success. If compactness is dropped as a requirement for our plasma-chemical reactor so that it is applicable to stationary rather than mobile power generators, then the reactor needs only 5% of the engine`s power. The energy inefficient component of the reactor, the part which makes our reactor compact, would be unnecessary. Thus our reactor has the potential for being a practical device to remove the NO{sub x} from the emissions of power plants.
Date: June 1, 1996
Creator: Chang, B. & Garcia, M.
Partner: UNT Libraries Government Documents Department

VAMOS: The verification and monitoring options study: Current research options for in-situ monitoring and verification of contaminant remediation and containment within the vadose zone

Description: The Verification and Monitoring Options Study Project (VAMOS) was established to identify high-priority options for future vadose-zone environmental research in the areas of in-situ remediation monitoring, post-closure monitoring, and containment emplacement and verification monitoring. VAMOS examined projected needs not currently being met with applied technology in order to develop viable monitoring and verification research options. The study emphasized a compatible systems approach to reinforce the need for utilizing compatible components to provide user friendly site monitoring systems. To identify the needs and research options related to vadose-zone environmental monitoring and verification, a literature search and expert panel forums were conducted. The search included present drivers for environmental monitoring technology, technology applications, and research efforts. The forums included scientific, academic, industry, and regulatory environmental professionals as well as end users of environmental technology. The experts evaluated current and future monitoring and verification needs, methods for meeting these needs, and viable research options and directions. A variety of high-priority technology development, user facility, and technology guidance research options were developed and presented as an outcome of the literature search and expert panel forums.
Date: September 1, 1995
Creator: Betsill, J.D. & Gruebel, R.D.
Partner: UNT Libraries Government Documents Department

The potential effect of future energy-efficiency and emissions-improving technologies on fuel consumption of heavy trucks.

Description: Researchers at Argonne National Laboratory analyzed heavy-duty truck technologies to support the Energy Information Administration's long-term energy use projections. Researchers conducted an analysis of several technology options that have potential to improve heavy truck fuel economy and emissions characteristics. The technologies are grouped as fuel-economy-enhancing and emissions-improving. Each technology's potential impact on heavy truck fuel economy has been estimated, as has the cost of implementation. The extent of technology penetration is estimated on the basis of truck data analyses and technical judgment.
Date: March 14, 2003
Creator: Vyas, A.; Saricks, C. & Stodolsky, F.
Partner: UNT Libraries Government Documents Department

Contamination Control Techniques

Description: Welcome to a workshop on contamination Control techniques. This work shop is designed for about two hours. Attendee participation is encouraged during the workshop. We will address different topics within contamination control techniques; present processes, products and equipment used here at Hanford and then open the floor to you, the attendees for your input on the topics.
Date: May 16, 2000
Creator: EBY, J.L.
Partner: UNT Libraries Government Documents Department