Energy-From-Waste and Dioxin Emission Control: Is There a Role for PVC Separation?

The role that chlorine and polyvinyl chlorine (PVC) plays in dioxin emissions from municipal solid waste (MSW) combustion has been studied and debated for 25 years. Despite energy-from-waste (EfW) facilities’ dramatic emission reductions following implementation of USEPA’s Maximum Achievable Control Technology (MACT) Guidelines, the PVC/dioxin relationship remains a source of controversy. The issue is whether removal of PVC from waste to be combusted will result in further dioxin emission reductions, as waste separation proponents allege. This paper uses the large volume of post-MACT emission testing data to describe the relationship between MSW chlorine content and dioxin emissions at operating EfW facilities and thereby determines whether PVC separation is likely to be an effective component of a dioxin emission reduction strategy. The paper also shows chlorine and PVC contents and trends in MSW, reviews dioxin formation/destruction/collection mechanisms in EfW facilities, and presents emission data as a function of EfW facility designs. The paper concludes that dioxin emissions at existing EfW facilities are insensitive to MSW chlorine content and that pre-combustion PVC removal offers no discernable emission reduction benefit.

A Carbon Injection System on a COHPAC-Equipped Waste-to-Energy Facility

The SEMASS Resource Recovery Facility (SEMASS) is a processed refuse fuel (PRF) waste-to-energy plant serving much of Southeastern Massachusetts. Units 1 and 2 at the plant were designed with spray dryer absorbers (SDAs) and electrostatic precipitators (ESPs). A review of historical data from the plant indicated that in order to comply with the Environmental Protection Agency’s Municipal Waste Combustor (MWC) Rule (40 CFR Part 60, Subpart Cb), which is known as the Maximum Achievable Control Technology (MACT), improved emission performance would be required from the flue gas cleaning system on Units 1 and 2. A pilot test program was conducted which led to the installation of COHPAC, or COmpact Hybrid PArticulate Collector units (i.e. flue gas polishing devices) downstream of the ESPs on these two combustion trains. The COHPAC units were successfully started up in June, 2000. In addition to these modifications, it was determined that further control of mercury emissions would be required. A system to inject powdered activated carbon into the flue gas was added to the plant. This paper describes that carbon injection system. A comparison between test data obtained at SEMASS is made with predictions based upon the EPA testing at the Ogden Martin Systems of Stanislaus, Inc. Municipal Waste Combustor Facility near Crows Landing, California and the EPA testing at the Camden County Municipal Waste Combustor in Camden, New Jersey. These are waste-to-energy plants, the former utilizing an SDA and a baghouse while the latter contains an SDA followed by an ESP. In addition, the effect of carbon injection location upon mercury reduction was investigated. The results of that study are also included.

Maximum Achievable Control Technology: What a Shipbuilder Should Know for Environmental Compliance

The new system for the control of air toxics being developed by the United States Environmental Protection Agency called the "Maximum Achievable Control Technology" requires the development of technology based standards for Hazardous Air Pollutants within a specific industrial or commercial source category. This paper attempts to provide a comprehensive understanding of the rule and its applicability to shipbuilding and ship repair industry. The reasons for selecting California regulations as the shipyard maximum available control technology, the compliance procedures, the control technologies for paints as-supplied and paints as-applied and other general requirements under the MACT rule are discussed in detail in this paper.