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The Volatile Matter of Coal

Description: From Introduction Scope of Report: "This bulletin is a report on an investigation of the volatile matter in several typical coals-its composition and amount at different temperatures of volatilization. As the investigation is still in progress and will doubtless include other coals than those already examined, the bulletin may be considered a preliminary report, stating the problems studied, the methods used, and the results thus far obtained."
Date: 1912
Creator: Porter, Horace C. & Ovitz, F. K.
Partner: UNT Libraries Government Documents Department

Effective Use of Molecular Recognition in Gas Sensing: Results from Acoustic Wave and In-Situ FTIR Measurements

Description: To probe directly the analyte/film interactions that characterize molecular recognition in gas sensors, we recorded changes to the in-situ surface vibrational spectra of specifically fictionalized surface acoustic wave (SAW) devices concurrently with analyte exposure and SAW measurement of the extent of sorption. Fourier-lmnsform infrared external- reflectance spectra (FTIR-ERS) were collected from operating 97-MH2 SAW delay lines during exposure to a range of analytes as they interacted with thin-film coatings previously shown to be selective: cyclodextrins for chiral recognition, Ni-camphorates for Lewis bases such as pyridine and organophosphonates, and phthalocyanines for aromatic compounds. In most cases where specific chemical interactions-metal coordination, "cage" compound inclusion, or z stacking-were expected, analyte dosing caused distinctive changes in the IR spectr~ together with anomalously large SAW sensor responses. In contrast, control experiments involving the physisorption of the same analytes by conventional organic polymers did not cause similar changes in the IR spectra, and the SAW responses were smaller. For a given conventional polymer, the partition coefficients (or SAW sensor signals) roughly followed the analyte fraction of saturation vapor pressure. These SAW/FTIR results support earlier conclusions derived from thickness-shear mode resonator data.
Date: December 9, 1998
Creator: Bodenhofer, K,; Gopel, W.; Hierlemann, A. & Ricco, A.J.
Partner: UNT Libraries Government Documents Department

METHODOLOGY FOR THE NUMBER OF FILTERS NEEDED IN A WASTE BOX

Description: Waste in large waste boxes can generate volatile organic compounds (VOCs) and hydrogen. These waste boxes may or may not have flow paths out of them (although it is believed that most do). These boxes will be retrieved, sampled, and then coated with polyurea. After coating, filters will be installed in the box to keep the concentration of VOCs and hydrogen acceptably low. The MDSA requires that a vent path must be protected during application of the polyurea coating. If the box has been sampled then it is vented and the vent path must be protected. This report provides a model in which the user inputs the free volume of the waste box, sample concentration (ppm of total VOC or volume fraction hydrogen) along with the number of filters to be placed into the waste box lid. Using this information, the model provides an estimate of concentration vs. time or the number of filters needed to reduce the concentration by a specified fraction. If the equations from this report are placed into spreadsheets which are then used to demonstrate TSR compliance, the spreadsheets must come under the Software QA Plan for such documents. Chapters 2 and 3 present the theory. Chapter 4 presents the method with examples of its use found in Chapter 5. Chapter 6 provides the basis far the use of 1,000 ppm as the concentration below which the method is valid under any condition.
Date: May 17, 2007
Creator: MARUSICH, R.M.
Partner: UNT Libraries Government Documents Department

Total energy cycle energy use and emissions of electric vehicles.

Description: A total energy cycle analysis (TECA) of electric vehicles (EV) was recently completed. The EV energy cycle includes production and transport of fuels used in power plants to generate electricity, electricity generation, EV operation, and vehicle and battery manufacture. This paper summarizes the key assumptions and results of the EVTECA. The total energy requirements of EVS me estimated to be 24-35% lower than those of the conventional, gasoline-fueled vehicles they replace, while the reductions in total oil use are even greater: 55-85%. Greenhouse gases (GHG) are 24-37% lower with EVs. EVs reduce total emissions of several criteria air pollutants (VOC, CO, and NO{sub x}) but increase total emissions of others (SO{sub x}, TSP, and lead) over the total energy cycle. Regional emissions are generally reduced with EVs, except possibly SO{sub x}. The limitations of the EVTECA are discussed, and its results are compared with those of other evaluations of EVs. In general, many of the results (particularly the oil use, GHG, VOC, CO, SO{sub x}, and lead results) of the analysis are consistent with those of other evaluations.
Date: April 29, 1999
Creator: Singh, M. K.
Partner: UNT Libraries Government Documents Department

Maximum total organic carbon limit for DWPF melter feed

Description: DWPF recently decided to control the potential flammability of melter off-gas by limiting the total carbon content in the melter feed and maintaining adequate conditions for combustion in the melter plenum. With this new strategy, all the LFL analyzers and associated interlocks and alarms were removed from both the primary and backup melter off-gas systems. Subsequently, D. Iverson of DWPF- T{ampersand}E requested that SRTC determine the maximum allowable total organic carbon (TOC) content in the melter feed which can be implemented as part of the Process Requirements for melter feed preparation (PR-S04). The maximum TOC limit thus determined in this study was about 24,000 ppm on an aqueous slurry basis. At the TOC levels below this, the peak concentration of combustible components in the quenched off-gas will not exceed 60 percent of the LFL during off-gas surges of magnitudes up to three times nominal, provided that the melter plenum temperature and the air purge rate to the BUFC are monitored and controlled above 650 degrees C and 220 lb/hr, respectively. Appropriate interlocks should discontinue the feeding when one or both of these conditions are not met. Both the magnitude and duration of an off-gas surge have a major impact on the maximum TOC limit, since they directly affect the melter plenum temperature and combustion. Although the data obtained during recent DWPF melter startup tests showed that the peak magnitude of a surge can be greater than three times nominal, the observed duration was considerably shorter, on the order of several seconds. The long surge duration assumed in this study has a greater impact on the plenum temperature than the peak magnitude, thus making the maximum TOC estimate conservative. Two models were used to make the necessary calculations to determine the TOC limit.
Date: March 13, 1995
Creator: Choi, A.S.
Partner: UNT Libraries Government Documents Department

An Intelligent Modular Array System for the Monitoring of VOCs in the Environment

Description: The originally proposed project had one primary objective: TO develop a low cost integrated VOC measurement system, IMAS, that can detect, quantify, and report on chemical contaminants present in water, soil, and air in a minimally invasive manner. A two phase program was initially proposed. Phase 1 would investigate the critical performance and reliability limits of the technology, and Phase 2 would develop and demonstrate a fully integrated module in actual field conditions.
Date: July 1, 1998
Creator: Tolar, N. Jay
Partner: UNT Libraries Government Documents Department

Small-scale demonstration of nonthermal plasma VOC treatment at Tinker AFB

Description: Nonthermal plasma (NTP) technology is a promising candidate for the treatment of air pollutants. An NTP is different from a thermal plasma in that high energy electrons are used to create chemically active species without raising the gas to high temperatures. NTPs have the potential of simultaneous removal of multiple air pollutants with better control over treatment byproducts. A silent discharge plasma (SDP) configuration is one method of easily generating such a nonthermal plasma. Silent electrical discharge plasma (dielectric barrier) reactors can decompose gas-phase pollutants by free-radical attack or electron-induced fragmentation. The radicals or electrons are produced by the large average volume nonthermal plasmas generated in the reactor. In the past decade, the barrier configuration has attracted attention for destroying toxic chemical agents for the military, removing harmful greenhouse gases (oxides of sulfur and nitrogen - SO{sub x} and NO{sub x}), and treating other environmentally-hazardous chemical compounds (hydrocarbons, chlorocarbons, and chlorofluorocarbons). At the Los Alamos National Laboratory (LANL), the authors have been studying the silent discharge plasma for processing gaseous-based hazardous chemicals for approximately five years. The key objective is to convert hazardous or toxic chemicals into non-hazardous compounds or into materials which are more easily managed. The main applications have been for treating off-gases from thermal treatment units (e.g., incinerators, high-temperature packed bed reactors, arc melters; low-temperature thermal desorbers), and for abating hazardous air-pollutant emissions (e.g., industrial air emissions, vapors extracted from contaminated soil or groundwater).
Date: October 22, 1996
Creator: Korzekwa, R. A. & Rosocha, L. A.
Partner: UNT Libraries Government Documents Department

Retardation of volatile organic compounds in ground water in low organic carbon sediments

Description: It is postulated that adsorption onto aquifer matrix surfaces is only one of the processes that retard contaminants in ground water in unconsolidated sediments; others include hydrodynamic dispersion, abiotic/biotic degradation, matrix diffusion, partitioning to organic carbon, diffusion into and retention in dead-end pores, etc. This work aims at these processes in defining the K{sub d} of VOCs in sediments with low organic carbon content. Experiments performed include an initial column experiment for VOC (TCE and perchloroethylene(PCE)) retardation tests on geological materials, PCE and TCE data from LLNL sediments, and a preliminary multilayer sampler experiment. The VOC K{sub d}s in low organic carbon permeable aquifer materials are dependent on the VOC composition and independent of aquifer grain size, indicating that sorption was not operative and that the primary retarding factors are diffusion controlled. The program of future experiments is described.
Date: April 1, 1995
Creator: Hoffman, F.
Partner: UNT Libraries Government Documents Department

Automated detection and reporting of Volatile Organic Compounds (VOCs) in complex environments

Description: This paper describes results from efforts to develop VOC sensing systems based on two complementary techniques. The first technique used a gated channeltron detector for resonant laser-induced multiphoton photoionization detection of trace organic vapors in a supersonic molecular beam. The channeltron was gated using a relatively simple circuit to generate a negative gate pulse with a width of 400 ns (FWHM), a 50 ns turn-on (rise) time, a 1.5 {mu}s turn-off (decay) time, a pulse amplitude of {minus}1000 Volts, and a DC offset adjustable from zero to {minus}1500 Volts. The gated channeltron allows rejection of spurious responses to UV laser light scattered directly into the channeltron and time-delayed ionization signals induced by photoionization of residual gas in the vacuum chamber. Detection limits in the part-per-trillion range have been demonstrated with the gated detector. The second technique used arrays of surface acoustic wave (SAW) devices coated with various chemically selective materials (e.g., polymers, self assembled monolayers) to provide unique response patterns to various chemical analytes. This work focused on polymers, formed by spin casting from solution or by plasma polymerization, as well as on self assembled monolayers. Response from coated SAWs to various concentrations of water, volatile organics, and organophosphonates (chemical warfare agent simulants) were used to provide calibration data. A novel visual empirical region of influence (VIERI) pattern recognition technique was used to evaluate the ability to use these response patterns to correctly identify chemical species. This investigation shows how the VERI technique can be used to determine the best set of coatings for an array, to predict the performance of the array even if sensor responses change due to aging of the coating materials, and to identify unknown analytes based on previous calibration data.
Date: March 1, 1997
Creator: Hargis, P.J. Jr.; Preppernau, B.L. & Osbourn, G.C.
Partner: UNT Libraries Government Documents Department

Test of a chemical dispersant for the control of scale formation at treatment facility D

Description: At the Lawrence Livermore National Laboratory (LLNL), ground water is being treated to remove contaminants such as volatile organic compounds and chromium by several types of processes. At Treatment Facility D, remediation of volatile organics is accomplished by sparging the water with air, and the chromium is removed by an ion- exchange process. The air stripping has the effect of raising the pH of the water from -7 to -8, probably as result of removing carbon dioxide from the water. In the absence of further water treatment, calcium carbonate (CaCO{sub 3}), or calcite, deposits on the downstream equipment as a scale, which causes operational problems. At present, this scale deposition is being controlled by the addition of a polyphosphate formulation (JP-7, Jaeger Products, Inc, Houston, TX), but the use of this chemical is not completely satisfactory because of stringent phosphate discharge limits for the treated water A more benign method of scale control would be highly desirable. Therefore, we evaluated an organic chemical dispersant as a possible alternative.
Date: May 1, 1998
Creator: Krauter, P., LLNL
Partner: UNT Libraries Government Documents Department

Concrete sample point: 304 Concretion Facility

Description: This report contains information concerning the analysis of concretes for volatile organic compounds. Included are the raw data for these analysis and the quality control data, the standards data, and all of the accompanying chains-of-custody records and requests for special analysis.
Date: March 10, 1995
Creator: Rollison, M.D.
Partner: UNT Libraries Government Documents Department

Barometric pumping with a twist: VOC containment and remediation without boreholes

Description: Objectives of Phase I (completed Nov. 1995) was to evaluate the feasibility of applying surface sealing and venting features to contain and remediate volatile organic compound (VOC) contaminated soils in the vadose zone. In Phase II, the remediation system will be installed at the Radioactive Waste Management Complex of INEL. It will cover an area of the landfill known to be contaminated with chlorinated hydrocarbons, deposited in shallow trenches. Operation will be monitored for 12 to 18 months to evaluate the impact on soil gas displacement. The 4 key components are the surface seal, plenum, vent assembly, and soil vapor monitoring points.
Date: December 31, 1996
Creator: Lowry, W.; Dunn, S.D. & Neeper, D.
Partner: UNT Libraries Government Documents Department

Remediation tradeoffs addressed with simulated annealing optimization

Description: Escalation of groundwater remediation costs has encouraged both advances in optimization techniques to balance remediation objectives and economics and development of innovative technologies to expedite source region clean-ups. We present an optimization application building on a pump-and-treat model, yet assuming a prior removal of different portions of the source area to address the evolving management issue of more aggressive source remediation. Separate economic estimates of in-situ thermal remediation are combined with the economic estimates of the subsequent optimal pump-and-treat remediation to observe tradeoff relationships of cost vs. highest remaining contamination levels (hot spot). The simulated annealing algorithm calls the flow and transport model to evaluate the success of a proposed remediation scenario at a U.S.A. Superfund site contaminated with volatile organic compounds (VOCs).
Date: February 1, 1998
Creator: Rogers, L. L., LLNL
Partner: UNT Libraries Government Documents Department

Holding time study of volatile organic compounds in SUMMA canisters

Description: According to this work, the headspace concentration of VOC`s is not changing measurably with time. That is, no appreciable uncertainty is added to the analysis of VOC`s in the headspace of storage drums by storage of the samples in SUMMA canisters for greater than 28 days.
Date: May 1, 1995
Creator: Reedy, G.T.; Applegate, D.V.; Gritters, M.A.; Carpenter, S.E. & Boparai, A.S.
Partner: UNT Libraries Government Documents Department

Dumping pump and treat: rapid cleanups using thermal technology

Description: Underground spills of volatile hydrocarbons are often difficult to clean up, especially if the contaminants are present in or below the water table as a separate liquid-organic phase. Excavating and treating the contaminated soil may not be practical or even possible if the affected zone is relatively deep. Merely pumping groundwater has proven to be ineffective because huge amounts of water must be flushed through the contaminated area to clean it; even then the contaminants may not be completely removed. Due to the low solubility of most common contaminants, such pump and treat systems can be expected to take decades to centuries to actually clean a site. Today, many sites are required to pump and treat contaminated groundwater even though there is no expectation that the site will be cleaned. In these cases, the pumps simply control the spread of the contaminant, while requiring a continuous flow of money, paperwork, and management attention. Although pump and treat systems are relatively inexpensive to operate, they represent along term cost. Most importantly, they rarely remove enough contaminant to change the property`s status. Although a pump and treat system can offer compliance in a regulatory sense, it doesn`t solve the site`s liability problem. Thermal methods promise to solve this dilemma by actually cleaning a property in a short time period, thus limiting the period of liability. This may involve cleaning a site to closure during the initial contaminant-removal phase, or removal of the majority of the contaminant so that natural processes such as bioremediation can return the site to pristine condition over a period of years, without further owner intervention. Today`s regulatory environment encourages this approach through efforts such as the brownfields initiatives. In either case, this requires a strong commitment on the part of the site owner. Most if not all the ...
Date: March 11, 1997
Creator: Newmark, R.L. & Aines, R.D.
Partner: UNT Libraries Government Documents Department

Monitoring and data analysis for the Vadose Zone Monitoring System (VZMS), McClellan AFB. Quarterly status report

Description: This report contains information on field and laboratory work performed between January and May 15th 1997 at site S-7 in IC 34, at McClellan AFB. At this location, a Vadose Zone Monitoring System (VZMS) is currently being used to collect subsurface data including hydraulic potential, soil gas pressure, moisture content, water chemistry, gas chemistry, and temperature. Due to delays in the completion of the above-ground installations, data collection did not commence until mid-February. As a result, the data presented in this report is preliminary.
Date: May 28, 1997
Creator: Zawislanski, P.T.; Salve, R. & Freifeld, B.
Partner: UNT Libraries Government Documents Department

Review of analytical results from the proposed agent disposal facility site, Aberdeen Proving Ground

Description: Argonne National Laboratory reviewed the analytical results from 57 composite soil samples collected in the Bush River area of Aberdeen Proving Ground, Maryland. A suite of 16 analytical tests involving 11 different SW-846 methods was used to detect a wide range of organic and inorganic contaminants. One method (BTEX) was considered redundant, and two {open_quotes}single-number{close_quotes} methods (TPH and TOX) were found to lack the required specificity to yield unambiguous results, especially in a preliminary investigation. Volatile analytes detected at the site include 1, 1,2,2-tetrachloroethane, trichloroethylene, and tetrachloroethylene, all of which probably represent residual site contamination from past activities. Other volatile analytes detected include toluene, tridecane, methylene chloride, and trichlorofluoromethane. These compounds are probably not associated with site contamination but likely represent cross-contamination or, in the case of tridecane, a naturally occurring material. Semivolatile analytes detected include three different phthalates and low part-per-billion amounts of the pesticide DDT and its degradation product DDE. The pesticide could represent residual site contamination from past activities, and the phthalates are likely due, in part, to cross-contamination during sample handling. A number of high-molecular-weight hydrocarbons and hydrocarbon derivatives were detected and were probably naturally occurring compounds. 4 refs., 1 fig., 8 tabs.
Date: September 1, 1997
Creator: Brubaker, K.L.; Reed, L.L.; Myers, S.W.; Shepard, L.T. & Sydelko, T.G.
Partner: UNT Libraries Government Documents Department

Biotic and Abiotic Transformation of a Volatile Organics Plume in a Semi-Arid Vadose Zone

Description: An evaluation of biotic and abiotic attenuation processes potentially important to chlorinated and non-chlorinated volatile organic compound (VOC) fate and transport in the 148 meter thick vadose zone beneath the Chemical Waste Landfill (CWL) was conducted. A unique feature of this evaluation is the comparison of two estimates of VOC mass present in the soil gas, pore-water, and solid phases (but not including mass as non-aqueous phase liquid [NAPL]) of the vadose zone in 1993. One estimate, 1,800 kg, was obtained from vadose zone transport modeling that incorporated molecular diffusion and volatilization to the atmosphere, but not biotic or chemical processes. The other estimate, 2,120 kg, was obtained from the sum of VOC mass physically removed during soil vapor extraction and an estimate of VOC mass remaining in the vadose zone in 1998, both adjusted to exclude NAPL mass. This comparison indicates that biogeochemical processes were at best slightly important to historical VOC plume development. Some evidence of aerobic degradation of non-chlorinated VOCs and abiotic transformation of 1,1,1-Trichloroethane was identified. Despite potentially amenable site conditions, no evidence was found of cometabolic and anaerobic transformation pathways. Relying principally on soil-gas analytical results, an upper-bound estimate of 21% mass reduction due to natural biogeochemical processes was developed. Although available information for the CWL indicates that natural attenuation processes other than volatilization to the atmosphere did not effective y enhance groundwater protection, these processes could be important in significantly reducing groundwater contamination and exposure risks at other sites. More laboratory and field research is required to improve our collective ability to characterize and exploit natural VOC attenuation processes, especially with respect to the combination of relatively thick and dry vadose zones and chlorinated VOCs.
Date: April 8, 1999
Creator: Studer, J.E.; Singletary, M.A. & Miller, D.R.
Partner: UNT Libraries Government Documents Department

Top-of-Rail lubricant

Description: Analysis of the volatile and semivolatile fractions collected after use of the TOR lubricant indicated that other than contaminants in the collection laboratory, no compounds on the EPA's Target Compound Lists (Tables 2 and 5) were detected in these fractions. The data of these qualitative analyses, given in the various tables in the text, indicate only the relative amounts of the tentatively identified compounds. The authors recommend that quantitative analysis be performed on the volatile and semivolatile fractions to allow confirmation of the tentatively identified compounds and to obtain absolute amounts of the detected compounds. Additionally, the semivolatile fraction should be analyzed by liquid chromatography/mass spectrometry to identify compounds that are not chromatographable under the temperature program used for determination of semivolatile compounds. Introducing the top-of-rail (TOR) lubricant into the wheel/rail interface results in a reduction of almost 60% of lateral friction force over the forces encountered under dry conditions. This reveals good potential for energy savings, as well as wear reduction, for railroad companies. In TOR lubrication, an increase in the angle of attack and axle load results in increased lateral friction and rate of lubricant consumption. The most efficient TOR lubricant quantity to be used in the wheel/rail interface must be calculated precisely according to the number of cars, axle loads, train speed, and angle of attack.
Date: July 14, 2000
Creator: Alzoubi, M. F.; Fenske, G. R.; Erck, R. A. & Boparai, A. S.
Partner: UNT Libraries Government Documents Department

Corrective Action Decision Document/Closure Report for Corrective Action Unit 263: Area 25 Building 4839 Leachfield, Nevada Test Site, Nevada

Description: This Corrective Action Decision Document/Closure Report (CADD/CR) has been prepared for Corrective Action Unit (CAU) 263, Area 25 Building 4839 Leachfield, in accordance with the Federal Facility Agreement and Consent Order. Corrective Action Unit 263 is located in the southwestern part of the Nevada Test Site in Nevada and includes one Corrective Action Site (CAS), CAS 25-05-04 Leachfield. This CADD/CR identifies and rationalizes the U.S. Department of Energy, Nevada Operations Office's (DOE/NV's) recommendation that no corrective action for CAU 263 is necessary. The Corrective Action Decision Document and Closure Report have been combined into one report because sample data collected during the April 1999 corrective action investigation (CAI) disclosed no evidence of contamination at the site. The purpose of the CAI was to identify the presence and the vertical and lateral extent of contaminants of potential concern (COPCs), specifically volatile organic compounds (VOCs) and semivola tile organic compounds (SVOCs) such as 1,4-dichlorobenzene and p-isopropyl toluene. The subsequent investigation included direct-push environmental soil samples from within the leachfield using a Geoprobe{reg_sign} unit; field screening of soil samples for radiological constituents and VOCs; submittal of environmental and quality control samples for testing for total VOCs, total SVOCs, and gamma spectrometry; and collection of soil samples from both the liquid phase and the underlying sludge of the septic tank contents. The CAI activities determined that: (1) all total VOC and total SVOC results were below the preliminary action levels outlined in the Corrective Action Investigation Plan (CAIP), and (2) radiological results were not distinguishable from background concentrations identified in the CAIP. Therefore, the DOE/NV recommended that no corrective action was required at CAU 263. No use restrictions were required to be placed on the CAU because the investigation showed no evidence of co ntamination at the site.
Date: October 1, 1999
Partner: UNT Libraries Government Documents Department

OZONE PRODUCTION IN URBAN PLUMES.

Description: Ozone levels observed during a field campaign in Houston were significantly higher than that observed in Phoenix or Philadelphia. An examination of the slope of O{sub x} versus NO{sub z} in the urban plumes shows that NO{sub x} is used 2 to 3 times more efficiently in Houston as compared with Phoenix and Philadelphia. Representative values of OPEx are 7-12, 3, and 4, in Houston, Phoenix, and Philadelphia. Aircraft observations have been used to calculate P(O{sub 3})/P(NO{sub z}). Values in Houston are significantly higher than in Phoenix and Philadelphia. We show that P(O{sub 3})/P(NO{sub z}) is proportional to a VOC/NO{sub 2}-OH reactivity ratio. High values of P(O{sub 3})/P(NO{sub z}) in Houston are due to emissions of reactive olefins from the ship channel region. It is significant that high values of P(O{sub 3})/P(NO{sub z}) occur at NO{sub x} levels up to several 10's of ppb. Not only is the chemistry efficient but it will be long lasting. The occurrence of high NO{sub x} and high OPEx is fostered by the co-location of VOC and NO{sub x} sources in the Houston industrial areas.
Date: September 17, 2001
Creator: KLEINMAN,L.
Partner: UNT Libraries Government Documents Department