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Dry Anaerobic Digestion

A state-of-the-art, high heat, dry anaerobic facility started converting organic waste into carbon-neutral biogas and high-grade natural compost in San Luis Obispo, on November 18, 2018. 

Zurich based Hitachi Zosen Inova (HZI) designed, financed, built, owns and operates the plant. HZI is a global leader in energy and material from waste solutions.

Kompogas SLO LLC
4300 Old Santa Fe Rd
San Luis Obispo, CA 93401

Kompogas SLO Digestion Plant.

What is Anaerobic Digestion?

HZI Plant diagram.

According to the EPA, "Anaerobic digestion is the natural process in which microorganisms break down organic materials. In this instance, 'organic' means coming from or made of plants or animals. Anaerobic digestion happens in closed spaces where there is no air (or oxygen). The initials 'AD' may refer to the process of anaerobic digestion or the built system where anaerobic digestion takes place, also known as a digester."

Environmental Protection Agency

Kompogas Plant Processing Steps

  1. Material reception, pre-treatment, and feeding
  2. Digestion
  3. Dewatering
  4. Press water loading
  5. Post-treatment of solid digestate – aerobic stablization
  6. Biogas Pre-Treatment

"The plant will process the organic solid waste at a thermophilic temperature of 131°F (55°C), considerably higher than the lower mesophilic temperature range of most of the state’s other anaerobic digestion facilities. The higher processing temperature ensures that spores and bacteria are eliminated, completely sanitizing the organic matter during processing. And equally important, the higher temperature permits the biogas potential to be fully exploited by the time the material comes out of the digester, extracting a higher volume of carbon-neutral biogas."

June 5, 2018 article by Jim McHanon published in
Kompogas pre-treatment plant.
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