Waste-To-Energy Gasification Plant

Case Study: Waste-To-Energy Gasification Plant

Summary: Progressive civic leaders in Covington, Tennessee, knew there was a better solution to disposing of wood waste and sludge – the ACE DDSF-1000 gasifier (12 tons/day).

Problem: The city of Covington wanted to find a better way to deal with wood waste and sludge – one that would eliminate costly trips to the landfills.

Approach: Aries Clean Energy developed the ACE DDSF-1000, a 12 ton per day capacity throughput downdraft gasification system that operates on the following specifications:

  • Input Materials: Wood is chipped, mixed with sludge, and pre-dried to control moisture content before gasification

  • Process: Syngas produced (92% by volume input) is combusted in an industrial thermal oxidizer (an emissions control device). Thermal energy is transferred to heat oil fluid, which drives a 235 Kw General Electric Organic Rankine Cylinder generator that offsets the electrical usage at the wastewater treatment plant next door.

  • Output: 8% of input results in biochar that is 70% carbon and recyclable

Results: The ACE DDSF-1000 downdraft gasification system yields waste, energy, and emissions benefits for Covington.

  • Waste: More than 4,000 tons diverted from landfills each year

  • Energy: More than 750,000 KWH generated over 20 year life of the project

  • Emissions: More than 900,000 lbs carbon emissions averted per year

  • Process: In July 2015, Aries assumed operation and fiscal responsibility for the plant, which is currently being used for advanced energy R&D purposes


Testimonial: I set out to find a way to utilize the waste our community generated. With this project, we have been able to literally turn trash into dollars.

- Dr. David Gordon, Mayor of Covington, 2004 – 2014