Many of the major chemical companies in the U.S. who regarded a safe environment as their responsibility installed waste treatment and disposal facilities on their plant sites in the last two decades. Many of these plants elected to use incinerators as the treatment process. This was not always the most economical method, but in many cases it was the only method of disposal that provided a safe and sure method of maximum destruction. Environmental concern over contamination from uncontrolled land disposal sites, and the emergence of tougher regulations for land disposal provide incentives for industry to employ a wide variety of traditional and advanced technologies for managing hazardous wastes. Incineration systems utilizing proper design, operation, and maintenance provides the safest, and in the long run, the most economical avenue to the maximum level of destruction of organic hazardous wastes.
A new ordinance on waste incinerators has extended the emission monitoring program. For all particularly relevant pollutants continuous measurements are required. In addition, the operation and reference quantities needed for checking proper operation and standardizing the measurements are measured continuously. The measurements are recorded and automatically evaluated by use of an electronic evaluation system. For these continuous measurements only measuring instruments which have successfully passed a suitability test program may be used. Compliance with the emission limits for heavy metals as well as for dioxins and furans is monitored by way of individual measurements.
The objective of the work presented here was to develop a technology for continuous measurement of stack gas emissions for compounds such as HCl, SO2, and NOx that was also capable of monitoring toxic hydrocarbons. The goal was to assure operators and local communities that the emission source is routinely operating in compliance with and well within the U.S. Environmental Protection Agency guidelines. A mass spectrometer-based continuous emissions monitoring system (CEMS) and its sample extraction system developed as a result of this work are described. Results of calibration drift, linearity, and accuracy tests for HCl, SO2, and NOx are presented. Results of CEMS tests are described that show the system has the performance capabilities necessary for a relatively inexpensive and frequent DRE demonstration.
A two chamber starved air incinerator was equipped with an emission control system for controlling the particulate, HCl, heavy metals and dioxins/furans emissions from a regional medical waste incinerator facility. The batch operation of the incinerator creates a wide variation of the flue gas temperatures and flow rates. The flue gas after cooling also contains unburned hydrocarbons besides the high moisture content. The daily startup and shutdown of the incinerator concomitant with the misunderstanding of the characteristics of the flue gas from the incineration operation has resulted in overhauling the system in less than three months. After the introduction of the Tesisorb, a cake modifying agent, and the modification of the system operation, the system is now in good operation. The characteristic of the incinerator operation as well as the performance of the emission control system is discussed.
A system for the real-time monitoring of emissions from incinerators must be developed which can address the needs of the DOE community and others involved in mixed waste incineration. These needs are an outgrowth of the ever-increasing waste storage problems and the growing concern of the public, as witnessed by the stricter compliance requirements of federal and state agencies, that the products of incineration are hazardous to their health and injurious to the environment. This paper focuses on the technologies being developed here at Los Alamos and other laboratories which address the detection of a broad spectrum of toxic and hazardous chemicals.
When applying the differential optical absorption spectroscopy (DOAS) technique for in-situ monitoring of flue-gas emissions, two main problems may occur in comparison to the atmospheric monitoring DOAS application. The first problem is due to the high and variable temperatures of flue gases, which significantly affects the magnitude of the differential absorption cross-sections. The second problem is caused by the limited choice of optical path- lengths, causing non-linearity effects due to large gas absorption. Measurements of the differential absorption cross-sections for NO, NO2, and SO2 have therefore been performed in a pyrex-glass cell contained in a heat-pipe, at temperatures between 20 and 400 degree(s)C, in the wavelength range of 205 to 440 nm. We also have performed measurements of the linear regions of the technique for measurements of SO2, NO2, and NO. The linear regions were shown to be 1 - 3200 mgm-2 for NO2, 0 - 2000 mgm-2 for SO2, and 0 - 120 mgm-2 for NO, in the spectral resolution range between 0.2 to 0.95 nm. The differential absorption cross-sections of NO2 and SO2 are strongly temperature dependent causing considerable errors in evaluated concentrations when using the DOAS technique. The relative errors due to temperature were of the order of 70% for SO2 and NO2 and of the order of 15% for NO at 400 degree(s)C.
Recently, considerable effort has been expended in order to discern multiple effluent constituents in stack gases with simplified analytical equipment. This quest has been driven by the sometimes painful experience of using a wide assortment of individual gas analyzers to measure the several common stack gases. The complexity of such analyzer systems, each with their own sources, detectors, and sampling components have fueled the quest for a new analysis technique that employs multi-component capability. To-date several innovative techniques have been tested, such as Photo-Acoustic and FTIR as well as others, but up to now none have achieved success equal to their promise. On the other hand, it has been shown that well proven, established techniques in IR spectroscopy can be used for most common stack gas measurements, and at the same time eliminate the complexity and reliability problems experienced with systems employing multiple individual gas analyzers. This paper explores the evolution of multi-component IR photometers and their application at a wide variety of sources for commonly measured effluent gases.
This article helps to define the state-of-the-art monitoring of hazardous, municipal, and medical waste incinerators -- what current regulations require and the capabilities of current monitoring systems. Recent conferences have highlighted new technologies for monitoring that may emerge in the next few years. Both laboratory and field tests are being conducted on combustion systems, power plants, and incinerators. There is intensive activity in this field. It is expected that the development of monitoring systems will provide the needed assurance that waste disposal systems can be monitored on a real-time basis. The public should be made aware of the present monitoring technology and its applications to incineration systems. The layperson must understand that we, the technical community, are as concerned with their health and safety as they are.
An important requirement in many industries is the ability to perform on-line monitoring and control of harsh, multi-phase process streams. During the last ten years, significant progress has occurred in the hardware and applications for Fourier transform infrared (FT-IR) spectroscopy. Instrumentation is now available which can perform, in harsh environments, continuous unattended and simultaneous measurements of absorbed (or reflected) and emitted radiation. The applications of FT-IR include: (1) concentrations of multiple species and phases (gases, liquid, particles, surfaces) as low as ppb; (2) temperatures of multiple species and phases (gases, liquid, particles, surfaces) with accuracies as good as +/- 1 degree(s)C at any elevated temperature; (3) measurement of particle sizes; (4) measurement of film thickness; (5) in-situ line-of-sight data; (6) in-situ spatially resolved data using tomography; (7) data on extracted samples; and (8) data on time scales as short as a few milliseconds.
The requirement to increase our understanding and control of processes has accelerated development of chemical sensor and analyzer technology. Analytical chemists anticipated the requirement to reduce the time between sampling and reporting the results. Multivariate statistical analyses when implemented on dedicated computers controlling modern instruments provide a mechanism for real time monitors. Implementation of these advanced techniques of analytical chemistry can also provide protection from environmental contaminants. The University of Alabama in Huntsville Laboratory For Inline Process Analyses has developed UV-visible-near infrared spectrophotometric methods that provide immediate, in-situ analyses. An appropriate light source illuminates the sample through a fiber optic. A second fiber then returns the reactance signal to the spectrophotometer. The spectrophotometer and computer are portable and can be used in a plant or by a field scientist. Implementation of computer programs based on multivariate statistical algorithms make possible obtaining immediate and reliable information from long data sets that may contain large amounts of extraneous information, for example, noise and/or analytes that we do not wish to control.
There exists little information concerning the quality of data generated from open-path Fourier transform infrared spectrometer (OP-FTIR) systems as applied to measuring toxic air pollutants. The U.S. Environmental Protection Agency, Region VII conducted a study designed to assess the intercomparability and data quality for several OP-FTIR systems. This paper describes the design of the study, presents the resulting data, and discusses the conclusions reached.
A mobile environmental laboratory has been developed. This laboratory consists of a van which is equipped with different environmental sensors. The FT-IR system K300 by Kayser- Threde is the key instrument. With this K300 the van can be used for remote measurements of the gaseous emissions from smoke stacks. In addition the laboratory is equipped with standard ambient air analyzers as well as meteorological sensors. A large battery system ensures current source free operation the whole day. Reloading of the batteries takes only one night. remote measurements with this van were carried out at different power plants. Several pollutants could be analyzed. First results are presented.
This paper describes a LIDAR instrument, specifically designed for in-field operation, which was developed to detect SO2-NO-CO concentration inside the combustion chamber of a power plant with a spatial resolution of 40 cm.
Infrared measurement using gas-filter correlation (GFC) detection offers an accurate, sensitive, and highly selective technique for the quantitative detection of a number of common industrial gases. A radiative transfer model based on the HITRAN database has been developed to permit the response function of such an instrument to be calculated. The model has been applied to a number of gases, calculating the instrument response to both the target gas and selected interferent species over a broad range of stack temperatures. An optical probe GFC detector has been designed for in-stack measurements of CO and HCl from incinerators and thermal power stations. The probe can be purged with clean air for a true baseline check and a calibration chamber is provided which allows the instrument to be calibrated using bottled gas mixtures. The instrument has completed a successful plant trial during which it measured CO emissions from a coal-fired power station, showing a detection sensitivity of 5 ppm. Detection of HCl has also been demonstrated in the laboratory.