The facility operates two (2) Municipal Solid Waste (MSW)-fired combustors (MWCs) capable of processing 690 tons per day and 214,000 tons per year. The facility’s mass burn combustion system incorporates the technology of German-based Martin GmbH. Waste is combusted at furnace temperatures exceeding 1,800 degrees Fahrenheit and reduced to an inert ash residue that is approximately 10% of its original volume. Before leaving the facility, combustion air is directed through technologically advanced air pollution control equipment including dry flue gas scrubbers and fabric filter baghouses. Facility emissions are strictly regulated by state and federal agencies as are handling and disposal of combustion ash. In addition to firing MSW, each unit is capable of firing auxiliary fuel, such as natural gas or fuel oil during startup and shutdown. The steam produced by the MWCs is sent to Redstone Arsenal.

• Diagram of Process (Diagram)
  
• Pollution Control
  • Air emissions are controlled by high efficiency combustion within the furnace/boiler as well as by selective non-catalytic reduction (SNCR), spray dryer absorbers, fabric filter baghouses and an activated carbon injection system.
    • Highly efficient combustion controls potential organic pollutants as well as carbon monoxide.
    • The SNCR system injects ammonia into the furnace to control nitrogen oxide emissions;
    • Spray dryer absorbers utilize a lime/water slurry mixture to control the boiler outlet gases. The lime slurry mixture neutralizes acid gases, such as sulfur dioxide and hydrogen chloride and cools the outlet gases as well;
    • The fabric filter baghouse removes particulate matter (fly ash) and provides a secondary acid gas neutralization surface on the filtercake; and,
    • The activated carbon injection system controls mercury emissions.
      
  • Covanta Huntsville, Inc. also utilizes state-of-the art continuous emissions monitoring systems (CEMS). The CEMS measures the stack gas for emissions, such as carbon monoxide, sulfur dioxide, nitrogen oxides, oxygen and opacity and allows the control room to continuously monitor the performance of each combustor unit. The CEMS data is reviewed and summarized into a report, which is routinely submitted to the Alabama Department of Environmental Management and EPA for review.