Homeland Security Research

Research Highlights

Gasification Technology Used in Biomass Removal

The disposal of contaminated animal carcasses in response to foreign animal disease outbreaks is an event- and site-specific operation that can have significant environmental impacts. For certain diseases, such as highly pathogenic avian influenza or foot-and-mouth disease, the U.S. Department of Agriculture recommends on‑site disposal in order to avoid the spread of disease. However, the options for on-site disposal of carcasses are limited.

For this reason, EPA has collaborated with the Department of Agriculture and the U.S. Department of Defense’s Technical Support Working Group (TSWG) to develop high-temperature gasification, an environmentally benign technology, in order to address the issue. This technology can be used to destroy large amounts of contaminated biomass, such as animal carcasses, and is designed to:

• Leave only an inert harmless ash residue
• Use minimal amounts of auxiliary fuel
• Be rapidly deployed

The Canadian Food Inspection Agency and Environment Canada are also partners in this project. BGP, Inc. has been contracted by TSWG to design and build a prototype gasifier. EPA will perform emissions testing on this prototype to assess its environmental impacts and to give regulatory decision makers information for permanent siting of these types of gasifiers.

Gasification Information and System Specifications

Gasification (see Figure 1) is a variant of conventional combustion that uses a staged injection of combustion air, resulting in a fuel-rich zone, followed by a fuel-lean zone. This technology uses smaller gas volumes than conventional combustion, making it attractive for use as a transportable system. The system operates under natural draft, which allows very low emissions of particulate matter without the need for complex pollution control equipment. A macerator will also be included to reduce the size of material fed into the system.

The gasifier (Figure 2) will be able to process 25 tons/day (scaleable to 150 tons/day with multiple units), and the macerator (Figure 3) will be capable of processing 150 tons/day. The gasifier will:

• Operate at a minimum temperature of 850 °C
• Be transportable with two tractor-trailer rigs
• Be deployed quickly and become fully operable less than 24 hours after arrival on site