Incineration of Hazardous Waste

The APCA Critical Review entitled "Incineration of Hazardous Waste" was presented by E. Timothy Oppelt, Chief, Thermal Destruction Branch, Alternative Technologies Division of U.S. EPA’s Hazardous Waste Engineering Research Laboratory (Cincinnati). Mr. Oppelt presented his review at the 80th APCA Annual Meeting & Exhibition, held in New York City in June 1987. The Critical Review paper, published in the May 1987 issue of JAPCA, examined the current state of knowledge regarding hazardous waste incineration in an effort to put the technical and environmental issues into perspective. Prepared discussions presented during the Critical Review session are published here, along with additional comments and closing remarks by Mr. Oppelt. Howard M. Ellis, Chairman of the Critical Review Subcommittee of the Publications Committee, served as moderator of the 1987 Critical Review session.     

Application of Dry Flue Gas Scrubbing to Hazardous Waste Incineration

Dry scrubbing of the flue gas from chemical waste incineration is becoming an increasingly viable alternative to wet scrubbing. This paper discusses the relative advantages and disadvantages of wet and dry scrubbing systems and compares the relative capital and operating costs. The design parameters of the dry scrubbing process are discussed, including reagent atomization, gas dispersion, gas temperatures, and particulate removal. The history of dry scrubbing process applications is discussed, including the successful European hazardous waste systems. Finally, a comparison is made among three very different hazardous waste incinerators in the U.S. that will utilize dry scrubbing systems.     

An Analysis of Biomedical Waste Incineration

The California Air Resources Board (ARB) completed a series of source tests of eight operating biomedical waste incinerators (BMWI) under conditions of typical operation. The emissions of certain metals, and chlorinated dioxins and furans in the flue gases of BMWI are relatively high in comparison to emissions from other combustion sources, such as hazardous waste or municipal waste incinerators of modern design. This study reports on an analysis of the status of the existing regulatory framework and the California data base. Clarification of definitional issues at the federal level is needed to effectively treat BMWI management issues. Although few relationships among combustion parameters and emissions were uncovered, patterns of emissions were evident, suggesting commonality and relationships among the waste stream constituents and emissions. Potential implications for future research, operation of BMWI, controls and source reduction and waste segregation strategies are also discussed.     

Screening Models for Estimating Toxic Air Pollution Near a Hazardous Waste Landfill

This paper is directed to environmental scientists concerned with assessing toxic air pollution downwind of hazardous waste landfills to determine whether potential health threats or exceedances of air quality standards exist. The purpose of this paper is to evaluate the performance of four air quality screening models.

The emission rate of vinyl chloride from the BKK co-disposal landfill in West Covina, California is estimated. Ambient vinyl chloride concentrations are estimated using a ground level point source model, two virtual point source models, arid the simple box model with meteorological and landfill input data representative of periods when ambient monitoring was conducted. The two virtual point source models are most precise and accurate in estimating 24-hour vinyl chloride concentrations. However, the results could include compensating errors in the emission rate and dispersion calculations because the emission rate estimate could not be independently evaluated.     

Evaluation of Canisters for Measuring Emissions of Volatile Organic Air Pollutants from Hazardous Waste Incineration

Regulation to control air emissions of toxic organic compounds require the collection and analysis of effluent gas from low level sources such as hazardous waste incinerators. The standard SW- 846 Method specifies the use of Tenax and Tenax/charcoal adsorbent traps for collection of volatile organics from incinerators. This study evaluates passivated stainless steel canisters as an alternative to adsorbent traps to eliminate some of the problems associated with adsorbent sampling. Initially the stability of 18 nonpolar, volatile organic compounds was determined in Summa-treated stainless steel canisters with greater than 100 ppmv HCI and saturated with water vapor. All 18 components were stable for a twoweek period; however, an Interference caused a 10-fold increase In the FID response of trlchloroethylene, toluene, and chlorobenzene. No Interference of the ECD response was found for any of the 11 compounds detected with the ECD including trlchloroethylene. A pilot scale incinerator was sampled using canisters, and the destruction efficiency of 1,1,1-trichloroethane was determined at a concentration of less than 0.5 ppbv while determining 1,1-dichloroethylene, the major product of Incomplete combustion, at a concentration of 8000 ppbv from the same sample.     

An Evaluation of Commercial Hazardous Waste Thermal Destruction Capacity

Thermal destruction capacity for commercial hazardous waste in the United States is examined to determine current and future capacity requirements. This study focuses on commercial incinerators and cement kilns burning conventional hazardous wastes. Aggregate maximum and available capacity estimates are derived using the most recent information. On a national basis, available capacity far exceeds present demand. On a regional basis, capacity appears sufficient with the exception of the California area. However, this shortfall appears insignificant given the overall capacity situation. While incineration demand may increase for solids and sludges as a consequence of Land Ban disposal restrictions and other reasons, capacity for these wastes again appears sufficient to meet current and projected demands. Thus, arguments that additional commercial incineration capacity will be needed to accommodate an expected increase in incinerable hazardous waste cannot be supported by the available information. The analysis raises concerns about the determination of realistic capacity estimates, and the lack of interaction between the capacity assurance process that documents the need for capacity and state siting processes for new waste management facilities. The excess incineration capacity shown in this paper will contribute to the successful implementation of EPA’s goal to reduce national capacity.     

Waste Incineration and Pulmonary Function: An Epidemiologic Study of Six Communities

ABSTRACT

This study investigated the chronic effects of emissions from three different waste incinerators on pulmonary function of both healthy and sensitive subjects with chronic respiratory symptoms. Participants were 8-80 years old, not currently smoking, and living in one of three communities each with an incinerator or one of three matched comparison communities. In total, 1018 subjects underwent a spirometric test once a year during 1992-1994. Exposure was assessed by three methods: living in an incinerator community; distance from the incinerator; and an incinerator exposure index, a function of the distance and direction of each subject's residence to the incinerator, days downwind, and average time spent outdoors. The results generally showed no statistically significant association between pulmonary function and these three incinerators, adjustment for gas oven/range use at home, length of residency, and smoking history in the mixed linear models. Two significant associations were that exposure to the hazardous waste incinerator in 1994 and to the municipal waste incinerator in 1993 were related to poor forced vital capacity. Sensitive subjects were not more adversely affected by incineration emissions than were hay fever or normal subjects. Possible explanations for the negative findings are low exposure levels and bias due to nondifferential misclassification of exposures.     

The 1984 Hazardous and Solid Waste Amendments: A Bold Experiment in Hazardous Waste Management

The 1984 amendments by Congress to the Resource Conservation and Recovery Act (RCRA) resulted primarily from a sense of frustration with EPA's apparent lack of progress in addressing the myriad problems associated with hazardous waste management. The amendments were also a manifestation of Congress’ clear sense of purpose in wanting to steer a radically different course at much greater speed. Whether this bold experiment works remains to be seen. EPA appears to be committed to carrying out both the letter and spirit of the Hazardous and Solid Waste Amendments of 1984, but no one should underestimate the magnitude of the task.     

Urea as a PCDD/F Inhibitor in Municipal Waste Incineration

ABSTRACT

Emissions of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) from municipal waste incineration have been widely studied because of their extensive toxicity, and many efforts have been made to restrict their emissions. Although a number of chemical compounds have been shown in laboratory-scale tests to inhibit the formation of PCDD/Fs, few have been tested in pilot- or full-scale plants. This work evaluates the effect of urea as a PCDD/F inhibitor in a pilot-scale incinerator that uses refuse-derived fuel (RDF). The decomposition of urea under the test conditions was also studied using detailed kinetic modeling. An aqueous solution of urea was injected into the flue gas stream after the furnace at ~730 °C, with varied urea concentrations and flue gas residence times used between the furnace and the sampling point. The results demonstrate that urea can successfully inhibit PCDD/F formation in waste incineration if concentrations and injection points are properly adjusted. The kinetic model showed that urea can be rapidly decomposed under appropriate flue gas conditions, indicating that in addition to the urea molecule itself, decomposition products of urea can also be responsible for the reduction of PCDD/F production during incineration.     

Hazardous Waste Minimization: Part VII (A) Hazardous Waste Minimization within the Department of Defense

This article is a series of representative case studies of Department of Defense hazardous waste minimization. Each Military Department and the Defense Logistics Agency describe actual accomplishments. Areas covered range from production line modification to product specification change. These efforts are part of a Department of Defense plan composed of individual programs executed independently by each military service and defense agency.

Part VII of the hazardous waste minimization series appears in two separate installments: this installment, Part VII (A), deals with Department of Defense waste minimization efforts in vehicle repair operations, explosives manufacturing, and abrasive blasting processes; Part VII (B) will cover shipboard mercury wastes, industrial chemical control, solvent reclamation, and hazardous property sales efforts.     

Reducing Risk in Hazardous Waste Management

Over the past several years, the Environmental Protection Agency has attempted to institutionalize an approach to its activities that is characterized by an active attempt to separate risk assessment from risk management activities. This approach, while not new in concept, has only been evolving at EPA for about four years. The Office of Research and Development, or ORD, has organized its research planning activities around this risk assessment-risk management concept. In order for the approach to succeed, it is necessary to develop the data and methodology necessary to undertake risk assessments both in the area of human health and ecology, and to develop methods to reduce those risks. Accordingly, we have organized our research planning into four major areas: Human Health Risk, Environmental or Ecological Risk, Exposure Assessment, and Risk Reduction. What I would like to do is outline briefly the breadth and diversity of EPA’s research program and the Agency’s research needs.     

Hazardous Waste Minimization: Part Vii (B) Hazardous Waste Minimization within the Department of Defense

This article is a series of representative case studies of Department of Defense hazardous waste minimization. Each Military Department and the Defense Logistics Agency describe actual accomplishments. Areas covered range from production line modification to product specification change. These efforts are part of a Department of Defense plan composed of individual programs executed independently by each military service and defense agency.

Part VII of the hazardous waste minimization series appears in two separate installments: the first installment, Part VII (A), dealt with Department of Defense waste minimization efforts in vehicle repair operations, explosives manufacturing, and abrasive blasting processes; Part VII (B) covers shipboard mercury wastes, industrial chemical control, solvent reclamation, and hazardous property sales efforts.     

Static Leaching of Solidified/Stabilized Hazardous Waste from the Soliditech Process

WILT, ANS 16.1 and TCLP leach tests were performed on solidified/stabilized (s/s) wastes treated by Soliditech, Inc. of Houston, Texas as part of a U.S. EPA SITE demonstration project conducted in December 1988 at the Imperial Oil Company/ Champion Chemical Company Superfund site in Morganville, New Jersey. All three leaching tests performed on the s/s wastes indicated that the primary contaminants of concern (lead and PCBs) were not leachable. The ANS 16.1 static leach test for the s/s wastes provided diffusion coefficients (D_e) for Al, Ca, and Na that were comparable to those obtained from the WILT test. However, plots of the ANS 16.1 data indicated that wetting of the samples confounded the static leaching process. The large column WILT D_e was used to estimate that less than 0.8 μg/cm² lead would leach from a one-cubic yard block of s/s waste in contact with groundwater over a 60-month leaching period. This corresponds to concentrations less than 10 μg/L lead in the water contacting the block of s/s waste.     

连云港经济技术开发区危废处置情况的调查研究

通过对连云港市经济技术开发区内医药企业危废产生及库存等情况进行调查,针对目前危废处理处置过程中存在问题,提出解决对策及建议。     

An Evaluation of the Semi-VOST Method for Determining Emissions from Hazardous Waste Incinerators

The Semi-Volatile Organic Sampling Train method was investigated to determine its reliability and to determine the bias and precision of the method when used to determine emissions from hazardous waste incinerators. Experiments showed that the matrix and sampling variables usually involved in sampling emissions from a hazardous waste incinerator had no significant effect on the recovery of 11 different organic compounds. Significant losses of the sampled compounds can occur during sample preparation. The degree of loss appears to be directly related to the compounds, vapor pressure. These losses can be corrected for by adding deuterated surrogates to the sample and analyzing the surrogates along with the native compounds.

The bias determination was based on dynamic spiking of the sampling train with five deuterated organic compounds selected from Appendix VIII of the Resource Conservation and Recovery Act regulations. The results show biases of from -1 ± 8 percent to -18 ± 27 percent for chlorinated and nonchlorinated compounds. Pyridine, a water-soluble compound, showed a larger bias of-29 ± 13 percent. Particular attention to the recovery of water soluble compounds is necessary to minimize bias in their determinations. Further work is needed to determine the reliability of laboratory-determined retention volumes that are used to determine sampling conditions.     

Dehalogenation Potential of Municipal Waste Incineration Fly Ash

BACKGROUND, AIMS AND SCOPE: In the first part of this paper the main principles which control the dehalogenation of polychlorinated aromatic compounds on municipal waste incineration fly ash (MWI-FA) have been discussed and the model fly ash of similar dehalogenation activity has been proposed. Even if both systems show comparable dehalogenation properties, the main question concerning the postulated identical reaction mechanism in both cases is left unanswered. The other very important point is to what extent is this dechlorination mechanism thermodynamically controlled. The same problem is often discussed in the literature also for the de novo synthetic reactions. From the data it is clear that metallic copper plays a decisive role in the mechanism of the dehalogenation reaction. Although the results reported in the first part strongly support the idea that copper acts in this dechlorination as the reaction component, in contrast to its generally accepted catalytic behaviour, we believed that additional support for this conclusion can be obtained with the help of a thermodynamic interpretation of the mechanism of the reaction. RESULTS AND DISCUSSION: The pathways of hexachlorobenzene dechlorination on MWI-FA and model fly ash were studied in a closed system at 260-300 degrees C under nitrogen atmosphere. These pathways were the same for both systems, with the following prevailing sequences: hexachlorobenzene --> pentachlorobenzene --> 1,2,3,5-tetrachlorobenzene --> 1,3,5-trichlorobenzene --> 1,3-dichlorobenzene. Thermodynamic calculations were carried out by using the method of minimization total Gibbs energy of the whole system. In the calculations, the following reaction components were taken into account: all gaseous chlorinated benzenes, benzene, hydrogen chloride, a gaseous trimer Cu3Cl3, and also Cu2O and CuCl2 as solid components. The effect of the reaction temperature and the amount of copper and water vapour were considered as well. The effect of reaction temperature was determined from the data calculated for the 500 to 750 K temperature region. The effect of the initial composition was determined for the molar amounts of copper = 0.01-3 moles and water vapour = 0.2 to 3 moles per mole of chlorobenzene isomer CONCLUSIONS: The results of hexachlorobenzene dechlorination by MWI-FA and model fly ash under comparable reaction conditions allow us to conclude that both dechlorinations proceed via the same dechlorination pathways, which can be taken as an evidence of the identical dehalogenation mechanism for both systems. The relative percentual distribution of the dehalogenated products depends on the temperature, but not on the initial amount of water vapour or copper metal. On the other hand, the initial amount of copper substantially affects the conversion of the dehalogenation as well as the molar ratio of Cu3Cl3 to HCl in the equilibrium mixture. Comparison of the experimental with thermodynamic results supports the idea that dehalogenation reactions are thermodynamically controlled. RECOMMENDATIONS AND OUTLOOK: Thermodynamic analysis of the dehalogenation reactions may prove useful for a wide range of pollutants. The calculations concerning polychlorinated biphenyls and phenols are under study.     

Refinery Sludge Treatment/Hazardous Waste Minimization Via Dehydration and Solvent Extraction

Abstract

The patented Carver-Greenfield (C-G) Process®, a combination of dehydration and solvent extraction treatment technologies, has a wide range of uses in separating hydrocarbon solvent-soluble hazardous organic contaminants (indigenous oil) from sludges, soils, and industrial wastes. As a result of this treatment, the products from a C-G Process facility are: ? Clean, dry solids which are typically suitable for disposal in nonhazardous landfills;

? Water which is treatable in an industrial or Publicly Owned Treatment Works (POTW) wastewater treatment facility;

? Extracted indigenous oil containing hydrocarbon soluble contaminants which may be recycled or reused or disposed of at less cost because its volume is smaller than the original waste feed.

The C-G Process was demonstrated on spent oily drilling fluids as part of the U.S. Environmental Protection Agency Superfund Innovative Technology Evaluation (SITE) Program. This paper summarizes the use of the C-G Process for economical treatment and minimization of hazardous refinery wastes, reviews the SITE program results, and describes extending the C-G Process technology to treatment of other wastes. Estimated treatment costs are presented.     

Investigation of Waste Oil Disposal by Direct Incineration

Most of the reliability analyses performed today assume that the system being considered is either in the operating state or in the failed state. However, there are systems in use which are considered to be operational even when they are in certain degraded states. An example is art electrostatic precipitator. This paper will take advantage of the special physical structure of a precipitator to obtain a mathematical model for its reliability. With appropriate modifications, this methodology can be extended to other systems.     

Cofiring Hazardous Waste Fuels in Industrial Processes

Although energy-intensive industrial processes have the potential to incinerate hazardous wastes while effecting fuel cost savings, increased government regulation and heightened public interest require that the financial aspects of a hazardous waste fuel (HWF) program be considered fully. Apparent fuel savings are offset by the capital requirements for institutional factors such as permitting and public relations. This paper provides cost information for initiating and operating a HWF program, and outlines the steps required to perform a thorough financial analysis. Falling fuel prices lessen the appeal of HWF programs, and unless the facility is paid to accept the HWF, only very large users (more than 80 × 10⁹ Btu/yr) of energy can consider them. The paper includes a figure from which the reader can estimate the return on investment for HWF programs over a range of program sizes (80 × 1200 × 10⁹ Btu/yr).     

危险废物处理技术进展及若干建议

较系统地论述了国内固体废物的目前状况、产量,分析了一些典型危险废物处理过程中存在的主要问题和解决方法,提出了深人开展危险废物处理与资源化研究的方向,并给出了环保部门应对危险废物进行处理的建议。