Commercial Waste-To-Energy Plant

Case Study: Commercial Waste-To-Energy Plant

Summary: The world’s largest downdraft gasifier was commissioned in October 2016 in Lebanon, Tennessee.

Problem: The city of Lebanon, Tennessee, wanted to find a new way of waste disposal that would eliminate landfill trips and expenses and improve its sustainability footprint.

Approach: Aries Clean Energy developed the PHG LF64 (64T/day) downdraft gasification system on one acre in Lebanon, Tennessee, that operates on the following specifications:

  • Input Materials: Waste wood is cut to 1- to 3-inch size; sludge is blended with wood 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 water, which drives three Organic Rankine Cylinder generators with a total output capacity of 420 Kw per day 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 Aries Clean Energy downdraft gasification system yields waste, energy, and emissions benefits for Lebanon, Tennessee:

  • Waste: More than 16 million pounds diverted from landfills each year

  • Energy: More than 36 MW-hrs generated over the 20 year life of the project

  • Emissions: More than 5,000 pounds of carbon emissions averted annually


Testimonial: This is such a great example of sustainability and could be a wonderful model for the rest of the world.

- Environmental Leader Awards Judge (June 2017)

Related Article