Principal Organic Hazardous Constituents Research Articles

Environmental Performance Test of Hazardous Waste Incinerator in Indonesia

One of the effective ways to reduce industrial hazardous and toxic wastes is to burn them in the incinerator. Advantages of hazardous and toxic waste incineration cause incinerator business in Indonesian to evolve. Besides, it is triggered by the availability of supporting regulations, such as the Regulation of the State Minister of Environment [1] that allows business people to have licenses to treat hazardous and toxic waste through incinerator. However, the operation of the hazardous and toxic waste incinerator must meet the performance test as regulated by the Government of Indonesia [2], such as destruction removal efficiency (DRE) of principal organic hazardous constituents (POHCs), combustion efficiency, gas residence time, concentration of emitted particulates and heavy metals, HCl and other gaseous pollutants. This paper presents the procedures and results of a case study of the trial burn test (TBT) conducted for the hazardous waste rotary kiln incinerator typically done in Indonesia.

Impact of incinerator internal hydrodynamics on hazardous organic waste destruction efficiency

The results of a study concerning the influence of internal hydrodynamics of incinerators on the principal organic hazardous constituents (POHCs) destruction efficiency are presented in this paper. A model of two tanks-in-series is used to describe internal hydrodynamics of incinerators via residence time distributions (RTD). Two cases corresponding, respectively, to the presence of a short-circuit and a deadwater zone within the internal flow are examined in detail. The results indicate that the incinerability ranking, based on plug-flow laboratory experiments for thermal stability determination, is disrupted. Temperatures required to obtain a conversion rate of 99.99% in a perturbed flow are higher. Simple relationships allow calculation of the temperature requirement deviation from the plug-flow case knowing the kinetic parameters of the waste combustion and the characteristics of the reactor hydrodynamics. This study shows that the selection of compounds to be spiked in the waste feed of an incinerator during a trial burn should be coupled to a direct determination of the residence time distribution of the incinerator itself for a proper selection of the compound that is more difficult to burn than any other organic expected in the actual waste. Methane, chlorobenzene and methyl chloride, which are characterized by a high stability whatever the species residence time distribution in the incinerator, are good candidates for trial burns.

Pilot-Scale Evaluation of an Incinerability Ranking System for Hazardous Organic Compounds

The U.S. Environmental Protection Agency’s (EPA) hazardous waste incinerator performance standards specify a minimum destruction and removal efficiency (DRE) for principal organic hazardous constituents (POHCs) designated in the incinerator waste feed. In the past, selection of appropriate POHCs for incinerator trial burns has been based largely on their heats of combustion. Attempting to improve upon this approach, the University of Dayton Research Institute (UDRI), under contract to the EPA Risk Reduction Engineering Laboratory, has developed a thermal stability-based ranking of compound incinerability. The subject study was conducted to evaluate the laboratory-developed ranking system in a pilot-scale incinerator. Mixtures of POHCs, spanning the ranking scale from most- to least-difficult to destroy (Class 1 to Class 7, respectively), were prepared and combined with a clay-based sorbent matrix. These mixtures were then fed into the rotary kiln incineration system at the U.S. EPA Incineration Research...

Assessment of off-normal emissions from hazardous waste incinerators Part 1. Assessment of off-normal emission frequency and duration

Abstract This is the first of two papers which report the results of a study of off-normal emissions from operation of a liquid injection hazardous waste incinerator. Reported in this paper are the results of off-normal emission frequency and duration assessment using probabilistic methods. The emissions from the incinerator are grouped into three categories: principal organic hazardous constituents (POHCs), particulates, and acid gases. The Integrated Reliability and Risk Analysis System (IRRAS) software is used for fault tree quantification and uncertainty analysis. The mean off-normal emission frequencies of each category are assessed as 0.24, 0.15 and 0.85 times per year for POHCs, particulates and acid gases respectively, and off-normal durations are modeled as log-normally distributed. The results of off-normal emission intensity and total off-normal emissions are reported in the second paper.

Assessment of off-normal emissions from hazardous waste incinerators

Abstract This is the second paper in a series of papers which report the results of a study of off-normal emissions from operation of a liquid injection hazardous waste incinerator. Reported in this paper are the results of off-normal emission intensity and total off-normal emissions using probabilistic methods. The results show that, in general, the total off-normal emissions per year for the scenarios analyzed are roughly the same magnitude as the total normal annual emissions for principal organic hazardous constituents (POHCs) and acid gases, and are much lower for particulates. Hence, it appears that for modern liquid injection incinerators, designed and operated according to the assumptions of this study, the off-normal emissions for any emission category may not be significantly large, large enough to increase the order of the magnitude of the overall risk, unless extremely toxic or dangerous wastes are incinerated, and a destruction and removal efficiency (DRE) of 99.9999% is sought.

Determination of selected principal organic hazardous constituents from incinerators using capillary column GC/MS

Abstract Laboratory and field experiments were conducted to evaluate the use of conventional capillary column GC/MS in the analysis of Volatile Organic Sampling Train (VOST) samples. The recovery of analytes and surrogates from replicate analysis was over 80% and the relative standard deviation less than 20 %. Field evaluations showed that the overall precision was less than 16% RSD; the recovery of surrogates was well within the system performance established by the EPA for a trial burn test of + 50% accuracy and 20% RSD precision.

Summary of POHC Audit Results Using VOST and Bag Methods During RCRA Trial Burns

Audit materials containing Principal Organic Hazardous Constituents (POHCs) have been developed by EPA for use by Federal, State, and Local agencies or their contractors to assess the accuracy of measurement methods used during RCRA trial burn tests. Audit materials are currently available for 27 gaseous organics in five-, six-, seven-, and nine-component mixtures at ppb levels (7 to 10,000 ppb) in compressed gas cylinders in a balance gas of nitrogen. The logic used in selecting 27 gaseous organic compounds as audit materials and how these audit materials are successfully used in performance audits is described. Stability studies indicate that all of the organics tested (with the exception of ethylene oxide and propylene oxide below 10 ppb levels) are stable enough to be used as reliable audit materials. As of January 1990, 215 performance audits have been conducted to assess the accuracy of Volatile Organic Sampling Train (VOST) and bag measurement methods during or prior to RCRA trial burn tests. A sum...

The potential of continuous emission monitoring of hazardous waste incinerators using Fourier transform infrared spectroscopy

This paper discusses the potential of Fourier transform infrared spectroscopy (FTIR) as a continuous emission monitor (CEM) for incinerator stack gas from hazardous and municipal waste. Mixtures of simulated incinerator gases and actual stack gas samples have been analyzed by FTIR, and the qualitative and quantitative results presented demonstrate the potential of FTIR as a CEM. The work discussed in this paper focuses on monitoring organics. Data are presented for two common principal organic hazardous constituents (POHC), chloroform and carbon tetrachloride, and three potential interferants: methylene chloride, methyl chloride, and perchloroethylene. Simulated mixtures of the above analytes demonstrated the capability of the equipment to identify target analytes in a complex matrix at the high ng/L (ppb) levels. Analysis of a bag sample of hazardous waste incinerator stack gas demonstrated the ability of the instrumentation to detect the POHC chloroform in a real-world sample. The results compared favorable with data obtained independently using the EPA approved GC/MS method.

Incinerability Ranking Systems For RCRA Hazardous Constituents

ABSTRACT The selection of Principal Organic Hazardous Constituents (POHCs) and determination of their incinerability ranking have been the subject of considerable scientific and policy debate since...

Screening Approach for Principal Organic Hazardous Constituents and Products of Incomplete Combustion

This paper is directed to those individuals concerned with developing or implementing screening strategies for characterizing organic emissions from incinerators and other combustion sources. The need to characterize hazardous waste incinerator emissions for multiple organic compounds has been steadily increasing for several years. The regulatory approach makes use of a type of indicator compounds procedure that concentrates on principal organic hazardous constituents (POHCs). In addition to continuing interest in POCHs, interest has been growing in the types and concentrations of products of incomplete combustion (PICs). Sampling and analysis methods have been developed previously for approximately 225 of the more important POHCs and PICs. These methods may be used as components of a cost-effective screening protocol aimed at maximum characterization of emissions, whether the project budget is large or small. This paper contains a discussion of fundamental principles of several kinds of screening strategies and recommends an approach suitable for incinerators and other combustion sources. The concept of a risk-driven analysis strategy is introduced and illustrated with a simplified example.

Performance audit results for volatile POHC measurements during RCRA trial burn tests.

Audit materials containing principal organic hazardous constituents (POHCs) have been developed by EPA for use by federal, state, and local agencies or their contractors to assess the accuracy of measurement methods used during RCRA trial burn tests. Audit materials are currently available for 27gaseous organics in five, six, seven, and nine-component mixtures at parts-per-billion levels (7 to 10,000 ppb) in compressed gas cylinders in a balance gas of nitrogen. The criteria used for the selection of 27 gaseous organic compounds is described. Stability studies indicate that all of the organics tested (with the exception of ethylene oxide and propylene oxide below 10 ppb levels) are stable enough to be used as reliable audit materials. Subsequent to completion of the stability studies, 89 performance audits have been conducted with the audit materials to assess the accuracy of the Volatile Organic Sampling Train (VOST) and bag measurement methods during or prior to RCRA trial burn tests. A summary of the a...

Potential health risk of hazardous waste incineration

Health risk estimates are presented for incineration of the principal organic hazardous constituents (POHCs) of waste streams. Preliminary results indicate that both the carcinogenic and the noncarcinogenic risks to populations living near incinerators are small. Further research is needed to confirm these results and to assess the human health risks from metals in waste streams and products of combustion formed during incineration.

Validation Studies of the Protocol for theVolatile Organic Sampling Train

The measurement of volatile organic emissions from a hazardous waste incinerator is one of the more difficult source testing problems. Specific compounds called principal organic hazardous constituents (POHC) are to be identified and quantified at levels of 0.5 to 100 ppb in hot, wet incinerator exhaust gas, which may also contain high particulate and acid levels. The Volatile Organic Sampling Train (VOST) Protocol which describes the practices used by laboratories making these measurements allows for several alternative designs and operating procedures. Because its use is currently being recommended by regulatory agencies to measure emissions for compliance determinations, the VOST Protocol was subjected to a methods validation study. The VOST Protocol validation program consists of two phases: a laboratory validation and a field test validation. The laboratory validation examined the results of sampling six different POHCs at two different concentration levels, two tube configuration designs, two moisture levels and other procedural variations. The Held test validation determined the expected precision and recovery results when spiking the gas stream of a hazardous waste incinerator with five specific POHCs. Recommendations relative to method improvements, quality assurance measures and other aspects of VOST sampling and analysis are also discussed.

Nonsteady-state testing of industrial boilers burning hazardous wastes

This paper presents test results on three industrial boilers cofiring liquid wastes spiked with hazardous organic compounds. The boilers tested comprise the major watertube design types: one gas- and oil-fired packaged boiler, one field erected gas-fired boiler, and one coal-fired stoker. Emission sampling included detailed evaluations of volatile and semivolatile organic pollutants in the flue gas for determinations of destruction and removal efficiency (DRE) of principal organic hazardous constituents (POHC) and emission of products of incomplete combustion (PIC) under several steady conditions and induced operational upsets. Overall the DRE of chlorinated organics exceeded 99.99% of the wastefeed, indicating efficient destruction of hazardous organics in the wastefeed under all boiler test conditions investigated including induced nonsteady and smoky operation. No statistically significant correlations were established between destruction efficiency of hazardous organics and boiler operating parameters such as steam load, O2 levels, CO, hydrocarbons, NOx, and smoke emission. Some tentative emission trends are highlighted.

On the Occurrence of Transient Puffs in a Rotary Kiln Incinerator Simulator I. Prototype Solid Plastic Wastes

In the operation of practical rotary kiln incinerators, the hazardous waste charge is often introduced in drums or containers in a batch mode. The ensuing transient condition, caused by the rapid devolatilization of waste materials, can momentarily deplete or displace local levels of excess oxygen in the kiln, resulting in heavy transient loadings of unburned gaseous and particulate hydrocarbons (here denoted as "puffs") leaving the kUn. This system upset must then be handled by an afterburner and subsequent air pollution control devices downstream. Such an overcharging or transient condition may even result in unacceptably low destruction of principal organic hazardous constituents (POHC) and the formation of products of incomplete combustion (PIC). A 73-kW (250,000-Btu/h) rotary kiln simulator was designed and constructed to provide engineering insight into the chemical and physical parameters associated with failure mode conditions. To this end, a statistically designed parametric investigation was undertaken to determine which waste and kiln variables (charge mass, charge surface area, charge composition, and kiln temperature) significantly affect both instantaneous intensity and total magnitude of the pollutant puffs leaving the kiln. Emphasis was on the incineration of simple prototype plastic wastes, ranging from polyethylene to polyvinyl chloride. Results demonstrate the relative ease with which failure conditions are experienced, even at high excess air values and high ktin temperatures. Transient puffs leaving the kiln contain a number of hazardous compounds. Increasing kiln temperature does not necessarily decrease the puff intensity and may in fact cause an increase. However, the total mass emitted decreases with increasing temperature. In addition, the mass, surface area, and composition of the charge are all important.

Analytical methods for determination of selected principal organic hazardous constituents in combustion products

The emissions from hazardous-waste combustion must be monitored to determine the destruction removal efficiency (DRE) for each designated principal organic hazardous constituent (POHC). Analytical methodology for more than 150 POHCs has been reviewed. A generalized high-resolution gas chromatography/low-resolution mass spectrometry (HRGC/LRMS) method to determine volatile, thermally stable POHCs has been developed. A method based on high-performance liquid chromatography (HPLC) with ultraviolet (UV) detection has also been developed to provide an alternative for the determination of nonvolative or thermally labile compounds. The generalized methods are applicable to many compounds, but specific POHCs may require variations in gas chromatography/mass spectrometry (GC/MS) or HPLC procedures. This paper will present an overview of the generalized procedures as well as some examples of the techniques used for compounds such as 2,3,7,8-tetrachlorodibenzodioxin, selenourea, and several organoarsenicals. 14 references, 5 figures, 4 tables.

Detecting waste combustion emissions

The disposal of hazardous wastes, especially organic chemicals, by incineration has been the subject of rapidly increasing interest during the past several years. When such wastes are incinerated, their composition is not the only characteristic that must be determined. Other factors of at least equal importance must be ascertained. These include the varieties and concentrations of any air contaminants that may be emitted during the incineration process. The presence or absence of contaminants shows how well a unit is operating and whether it will perform well enough to meet environmental standards. Research on developing adequate methods of sampling and analysis of the emissions is in progress. These sampling methods are generally applicable not only to incineration but also to processes closely related to incinerations, such as the cofiring of waste in industrial boilers and the burning of contaminated heating oil. Although this article briefly discusses methods for sampling inorganic hazardous compounds, its primary emphasis is on ways of sampling organic compounds likely to be designated as principal organic hazardous constituents (POHCs) for a trial burn.

Incinerability of Hazardous Wastes

A method for ranking the "incinerability" of principal organic hazardous constituents (POHCs) of a waste stream is of considerable practical use to those concerned with thermal disposal of hazardous materials. In this article, the technical aspects behind six previously proposed methods are examined and related to combustion processes occurring during full-scale thermal disposal. A simple two-zone incineration model has been developed that appears to demonstrate correctly the relevance of various parameters to incinerability. Thermal or post-flame decomposition of POHCs is shown to determine the relative incinerability (ranking) of listed, hazardous organic compounds. Furthermore, oxygen-starved portions of the post-flame region may be responsible for the majority of emissions of both POHCs and potentially toxic reaction products.

Evaluation of hazardous waste incineration in lime kiln: Rockwell lime company

During a one-week test burn, hazardous waste was used as supplemental fuel and co-fired with petroleum coke in a lime kiln in eastern Wisconsin. Detailed sampling and analysis was conducted on the stack gas for principal organic hazardous constituents (POHCs), particulates, particulate metals, HCl, SO 2, NO x, CO, and THC and on process streams for metals and chlorine. POHCs were also analyzed in the waste fuel. Sampling was conducted during three baseline and five waste fuel test burn days. Results show average destruction and removal efficiences (DREs) greater than 99.99% for each POHC and little change in pollutant emissions from baseline to waste fuel test conditons. In addtion, material balance results show that 95% of chlorine enters the process from the limestone fed and the chlorine exits the kiln in the baghouse dust and lime product at 61% and 38%, respectively.

Evaluation of Analytical Methods for the Determination of POHC in Combustion Products

As part of the Resource Conservation and Recovery Act (RCRA), the U.S. Environmental Protection Agency has proposed regulations for owners and operators who treat hazardous waste by incineration. To ensure that these incinerators operate in an environmentally responsible manner, the regulations Include a requirement that, for selected principal organic hazardous constituents (POHCs), a destruction and removal efficiency (DRE) of equal to or greater than 99.99% must be achieved (40 C.F.R. Part 264 §264.343). As part of the supporting documentation for permit writers and for the incinerator facility owners and operators, we have evaluated gas chromatography/mass spectrometry (GC/MS) and high performance liquid chromatography (HPLC) methods for the determination of about 150 compounds from the list of potential POHCs, as defined in 40 C.F.R. Part 261, Appendix VIII. The methods evaluated are presented, analytical results are given, and the application of the evaluated methods to the determination of POHCs in incinerator effluents is discussed.