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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


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

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

Factors Affecting Indoor Air Concentrations of Volatile Organic Compounds at a Site of Subsurface Gasoline Contamination

Description: We report a field study of soil gas transport of volatile organic compounds (VOCs) into a slab-on-grade building found at a site contaminated with gasoline. Although the high VOC concentrations (30-60 g m{sup -3}) measured in the soil gas at depths of 0.7 m below the building suggest a potential for high levels of indoor VOC, the measured indoor air concentrations were lower than those in the soil gas by approximately six orders of magnitude ({approx} 0.03 mg m{sup -3}). This large ratio is explained by (1) the expected dilution of soil gas entering the building via ambient building ventilation (a factor of {approx}1000), and (2) an unexpectedly sharp gradient in soil gas VOC concentration between the depths of 0.1 and 0.7 m (a factor of {approx}1000). Measurements of the soil physical and biological characteristics indicate that a partial physical barrier to vertical transport in combination with microbial degradation provides a likely explanation for this gradient. These factors are likely to be important to varying degrees at other sites.
Date: November 1, 1995
Creator: Fischer, M. L.; Bentley, A. J.; Dunkin, K. A.; Hodgson, A. T.; Nazaroff, W. W.; Sextro, R. G. et al.
Partner: UNT Libraries Government Documents Department

Enhanced Attenuation: A Reference Guide On Approaches To Increase The Natural Treatment Capacity Of A System

Description: The objective of this document is to explore the realm of enhancements to natural attenuation processes for cVOCs and review examples that have been proposed, modeled, and implemented. We will identify lessons learned from these case studies to confirm that enhancements are technically feasible and have the potential to achieve a favorable, cost-effective contaminant mass balance. Furthermore, we hope to determine if opportunities for further improvement of the enhancements exist and suggest areas where new and innovative types of enhancements might be possible.
Date: January 30, 2006
Creator: Vangelas, K
Partner: UNT Libraries Government Documents Department


Description: The objective of this document is to explore the realm of enhancements to natural attenuation processes for cVOCs and review examples that have been proposed, modeled, and implemented. We will identify lessons learned from these case studies to confirm that enhancements are technically feasible and have the potential to achieve a favorable, cost-effective contaminant mass balance. Furthermore, we hope to determine if opportunities for further improvement of the enhancements exist and suggest areas where new and innovative types of enhancements might be possible.
Date: August 10, 2006
Creator: Looney, B; Michael Heitkamp, M; Gary Wein (NOEMAIL), G; Karen Vangelas, K; Karen-M Adams, K; Early, Tom et al.
Partner: UNT Libraries Government Documents Department

Subtask 1.15-Passive Diffusion Sample Bags Made from Expanded Polytetrafluorethylene (ePTFE) to Measure VOC Concentrations in Groundwater

Description: With laboratory testing of expanded polytetrafluoroethylene (ePTFE) membranes complete, collected data support that volatile organic compound (VOC) molecules will readily diffuse across ePTFE membranes. Membrane samples, supplied by BHA Technologies (GE Osmonics), were tested to determine diffusion rates for VOCs in groundwater. Tests were conducted using membranes with two different pore sizes, with and without thermally laminated spun bond backing, and multiple concentrations of contaminated groundwater. Results suggest that typical residence times associated with traditional samplers constructed of polyethylene (2 weeks) can be reduced by 1 week using ePTFE membranes (reducing project costs) and that VOCs will diffuse more readily at lower temperatures (2.2-3.3 C) across ePTFE materials.
Date: August 1, 2006
Creator: Botnen, Barry W.
Partner: UNT Libraries Government Documents Department

JV Task 86 - Identifying the Source of Benzene in Indoor Air Using Different Compound Classes from TO-15 Data

Description: Volatile organic compound (VOC) data that had already been collected using EPA method TO-15 at four different sites under regulatory scrutiny (a school, strip mall, apartment complex, and business/residential neighborhood) were evaluated to determine whether the source of indoor air benzene was outdoor air or vapor intrusion from contaminated soil. Both the use of tracer organics characteristic of different sources and principal component statistical analysis demonstrated that the source of indoor air at virtually all indoor sampling locations was a result of outdoor air, and not contaminated soil in and near the indoor air-sampling locations. These results show that proposed remediation activities to remove benzene-contaminated soil are highly unlikely to reduce indoor air benzene concentrations. A manuscript describing these results is presently being prepared for submission to a peer-reviewed journal.
Date: April 15, 2007
Creator: Hawthorne, Steven B.
Partner: UNT Libraries Government Documents Department

Modeling Emissions of Volatile Organic Compounds from New Carpets

Description: A simple model is proposed to account for observed emissions of volatile organic compounds (VOCs) from new carpets. The model assumes that the VOCs originate predominantly in a uniform slab of polymer backing material. Parameters for the model (the initial concentration of a VOC in the polymer, a diffusion coefficient and an equilibrium polymer/air partition coefficient) are obtained from experimental data produced by a previous chamber study. The diffusion coefficients generally decrease as the molecular weight of the VOCs increase, while the polymer/air partition coefficients generally increase as the vapor pressure of the compounds decrease. In addition, for two of the study carpets that have a styrene-butadiene rubber (SBR) backing, the diffusion and partition coefficients are similar to independently reported values for SBR. The results suggest that predictions of VOCs emissions from new carpets may be possible based solely on a knowledge of the physical properties of the relevant compounds and the carpet backing material. However, a more rigorous validation of the model is desirable.
Date: February 1, 1993
Creator: Little, J.C.; Hodgson, A.T. & Gadgil, A.J.
Partner: UNT Libraries Government Documents Department

Sensitivity analysis of ozone formation and transport for a Central California air pollution episode

Description: CMAQ-HDDM is used to determine spatial and temporal variations in ozone limiting reagents and local vs upwind source contributions for an air pollution episode in Central California. We developed a first- and second- order sensitivity analysis approach with the Decoupled Direct Method to examine spatial and temporal variations of ozone-limiting reagents and the importance of local vs upwind emission sources in the San Joaquin Valley of central California for a five-day ozone episode (29th July-3rd Aug, 2000). Despite considerable spatial variations, nitrogen oxides (NO{sub x}) emission reductions are overall more effective than volatile organic compound (VOC) control for attaining the 8-hr ozone standard in this region for this episode, in contrast to the VOC control that works better for attaining the prior 1-hr ozone standard. Inter-basin source contributions of NO{sub x} emissions are limited to the northern part of the SJV, while anthropogenic VOC (AVOC) emissions, especially those emitted at night, influence ozone formation in the SJV further downwind. Among model input parameters studied here, uncertainties in emissions of NO{sub x} and AVOC, and the rate coefficient of the OH + NO{sub 2} termination reaction, have the greatest effect on first-order ozone responses to changes in NO{sub x} emissions. Uncertainties in biogenic VOC emissions only have a modest effect because they are generally not collocated with anthropogenic sources in this region.
Date: May 15, 2009
Creator: Jin, Ling; Tonse, Shaheen; Cohan, Daniel S.; Mao, Xiaoling; Harley, Robert A. & Brown, Nancy J.
Partner: UNT Libraries Government Documents Department

The Role of Heterogeneous Chemistry of Volatile ORganic Compounds: A Modeling and Laboratory Study

Description: Overview The outputs of this research have been reported annually via the RIMS system. This report serves as an update and final report. The focus of our DOE BES funded project is on the importance of heterogeneous reactions in the troposphere. The primary objectives of our study were to: (i) Evaluate the extent to which heterogeneous chemistry affects the photochemical oxidant cycle, particularly, sources and sinks of tropospheric ozone; and (ii) Conduct laboratory studies on heterogeneous reactions involving NOy, O3 and VOCs on aerosol surfaces. These objectives were pursued through a multidisciplinary approach that combines modeling and laboratory components as discussed in more detail below. In addition, in response to the reconfiguring of the Atmospheric Science Program to focus on aerosol radiative forcing of climate, we also began to investigate the radiative properties of atmospheric aerosol.
Date: March 1, 2007
Creator: Carmichael, Gregory R. & Grassian, Vicki H.
Partner: UNT Libraries Government Documents Department

Soil Samplers: New Techniques for Subsurface Sampling for Volatile Organic Compounds

Description: Soil sampling techniques for volatile organic analysis must be designed to minimize loss of volatile organic compounds (VOCs) from the soil that is being sampled. Preventing VOC loss from soil cores that are collected from the subsurface and brought to the surface for subsampling is often difficult. Subsurface bulk sample retrieval systems are designed to obtain intact cylindrical cores of soil ranging anywhere from one to four inches in diameter, and one to several feet in length. The current technique that is used to subsample these soil cores for VOC analysis is to expose a horizontal section of the soil core to the atmosphere; screen the exposed soil using a photoionization detector (PID) or other appropriate device to locate contamination in the soil core; and use a hand-operated coring tool to collect samples from the exposed soil for analysis. Because the soil core can be exposed to the atmosphere for a considerable length of time during screening and sample collection, the current sub-sampling technique provides opportunity for VOCs to be lost from the soil. This report describes three alternative techniques from the current technique for screening and collecting soil samples from subsurface soil cores for VOC analysis and field testing that has been done to evaluate the techniques. Based on the results of the field testing, ASTM D4547, Standard Guide for Sampling Waste and Soils for Volatile Organic Compounds, was revised to include information about the new techniques.
Date: March 31, 2009
Creator: Sorini, Susan; Schabron, John; Rovani, Joseph & Sanderson, Mark
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