Sewage sludge gasification ruling paves way for waste treatment technology

A recent EPA ruling that sewage sludge gasification technology is not an incinerator heralds a major victory for clean air and water.

WASHINGTON, DC, Jan. 2, 2014 -- A recent Environmental Protection Agency (EPA) ruling that sewage sludge gasification technology is not an incinerator heralds a major victory for clean air and water as well as for municipal taxpayers looking for a sustainable alternative to costly incineration.

The EPA, in a letter dated Dec. 19, determined that federal emissions guidelines and compliance rules for sewage sludge incinerators patented by MaxWest Environmental Systems Inc., do not apply to the comapny's sludge gasifier near Sanford, Fla. The ruling came in response to a request from McGuireWoods LLP, which represented the company before the regulatory agency.

In its findings, the EPA held that MaxWest's technology that breaks down sewage sludge through heating in an oxygen-starved environment prevents combustion, and thus will not be regulated as an incinerator. The agency further exempted the second energy-saving step in the process -- a "thermal oxidizer process heater" in which gases released from thermochemical reactions are scrubbed and then burned to create heat needed to dry incoming sludge.

Gasification produces a more valuable fertilizer for farmers since some of the carbon that incineration destroys remains in the solid byproduct. As space in landfills becomes scarce and motor fuel costs climb, the costs of hauling and disposing of sludge in them have skyrocketed. Accordingly, MaxWest's gasification technology eliminates air and groundwater pollution risks that landfill disposal of sludge poses. The result of the process is a self-sufficient closed-loop system that requires little or no fossil fuel after start-up, drastically reducing costs of and emissions from using natural gas for an incinerator.

MaxWest is in negotiations to deploy its technology in several municipalities across the United States. December's EPA ruling is not the first time the agency has cast a vote of confidence in MaxWest's technology. In a June 2012 report, the EPA extolled the benefits of its gasification process for its emissions control and green energy benefits and singled out MaxWest as the only domestic gasification technology ready for prime time.


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