Emission Control Residuals

This paper will discuss how some foundries have evaluated the application of these waste management options for calcium carbide desulfurization slag and melt emission control residuals. 

The emission control residuals sometimes exceeded EP Toxicity hazardous waste limits for lead and cadmium because the melting point of grey iron is approximately 2,700°F, where the melting point for lead is only about 620°F. As the metal is melted, the lead and cadmium will tend to volatilize and be collected by either the baghouse or wet dust collection emission control system. 

In a study (Boyle, et al., 1981) conducted by the American Foundrymen s Society (AFS) in conjunction with the University of Wisconsin and the USEPA, leaching tests were conducted on cupola emission control dusts and sludges from 21 different foundries. This study concluded that 9 out of the 21 foundries generated emission control residuals which would be considered as a hazardous waste on the basis of EP Toxicity for lead. Two other foundries generated emission control residuals which would be classified as hazardous on the basis of EP Toxicity for cadmium. Concentrations in the EP Toxicity Test for the 21 foundries ranged from less than 0.6 mg/1 to 130 mg/1. The mean lead... 

At this time, the USEPA has not "listed" melting emission control residuals from iron foundries as hazardous. It is unlikely that these wastes meet the characteristics of ignitability, corrosivity, or reactivity. However, some foundries clearly generate emission control residuals which meet the... 

A predominant source of lead and cadmium in the emission control residuals from foundry melting operations is the scrap material itself. Materials such as coke and certain fluxes contain much lower quantities of trace metals than does the scrap. 

Various chemical means have been used to reduce the leaching potential of toxic metals. The four types of chemical treatment applicable to emission control residual waste which are EP Toxic for lead or cadmium include the following ... 

Removal of metal chlorides from the bottoms of the Hquid-phase ethylene chlorination process has been studied (43). A detailed summary of production methods, emissions, emission controls, costs, and impacts of the control measures has been made (44). Residues from this process can also be recovered by evaporation, decomposition at high temperatures, and distillation (45). A review of the by-products produced in the different manufacturing processes has also been performed (46). Several processes have been developed to limit ethylene losses in the inerts purge from an oxychlorination reactor (47,48). 

Residuals Produced Liquid injection incinerators produce ash which may require application of a post treatment technology prior to disposal. The byproducts from the emission control devices may also require further treatment prior to disposal. 

Emission control from heavy duty diesel engines in vehicles and stationary sources involves the use of ammonium to selectively reduce N O, from the exhaust gas. This NO removal system is called selective catalytic reduction by ammonium (NH3-SGR) and it is additionally used for the catalytic oxidation of GO and HGs.The ammonia primarily reacts in the SGR catalytic converter with NO2 to form nitrogen and water. Excess ammonia is converted to nitrogen and water on reaction with residual oxygen. As ammonia is a toxic substance, the actual reducing agent used in motor vehicle applications is urea. Urea is manufactured commercially and is both ground water compatible and chemically stable under ambient conditions [46]. 

The facility would use a dry scrubber system for emission control, which would eliminate the need for wastewater treatment. Any water from emission control and from decontamination procedures would be treated in the on-site groundwater treatment system. The residual soil and collected ash is assumed to be nonhazardous and can be disposed of in a solid waste disposal facility in compliance with subtitle D of RCRA. In the event that they cannot be delisted due to the presence of metals, the residuals will be managed as part of the closure of Area 2 shown in Figure 16.21 (lead-contaminated soil). 

If an incinerator burns a listed hazardous waste, the ash is also considered a listed waste. The derived-from rule states that any solid waste generated from the treatment, storage, or disposal of a listed hazardous waste, including any sludge, spill residue, ash, emission control dust, or leachate, remains a hazardous waste unless and until it is delisted. The owner/operator must also determine whether the ash exhibits any of the characteristics of a hazardous waste. 

In response to recent federal and local environmental concerns (e.g., industrial emission controls and lead phase-out) and to the growing interest of refiners in cracking residual fuels, researchers have generated new families of cracking catalysts. There is now a need to review the merits of these newly developed materials. This volume contains contributions from researchers involved in the preparation and characterization of cracking catalysts. Other important aspects of fluid catalytic cracking, such as feedstocks and process hardware effects in refining, have been intentionally omitted because of time limitations and should be treated separately in future volumes. 

Based on data from the U.S. Environmental Protection Agency (EPA) Superfund Innovative Technology Evaluation (SITE) demonstration, the total cost for PF extraction was estimated to be 307/kg of trichloroethene (TCE) removed. This demonstration was conducted over a 4-week period in August and September of 1992 at an industrial site in Somerville, New Jersey. The cost estimate includes expenses associated with both PF and soil vapor extraction. Major cost factors were labor (29%), capital equipment (22%), VOC emission control (19%), site preparation (11%), and residuals management (10%) (D10589F, p. v). 

The TDT-3R (a)priinaTy desorption chamber, (b)condensation or burning of pyrolysis gas vapours and c)non destructive APCD off gas scrubber are separate devices, whereas (l)treated solids, (2)condensate residuals, (3)APCD residuals, (4)organic air emission, (S)metal air emission, (6)acid gas emission treatment are according to all the relevant comprehensive U.S. and E,U. regulatory requirements for Operational Control, Residuals and Air Emission Parameters. 

Site-specific issues impacting the selection of the control equipment, must be quantified. These include availability of utilities, pace constraints, disposal options, and cost of residue generated by emissions control. 

Residue or ash removal and handling systems Waste heat recovery boiler systems Emissions control systems Breeching, stacks and dampers Controls and instrumentation... 

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