Biogas and Renewable Natural Gas Production from Municipal Organic Waste

Abstract:

The purpose of this process is to convert municipal organic waste into pipeline quality renewable natural gas through anaerobic digestion and biogas upgrading. The plant will be located in Milton, ON with a capacity of 50,000 tonnes per year. The procedure includes six stages: pre-treatment, anaerobic digestion, moisture removal, sulfur removal, sulfur recovery, and a membrane train. High efficiencies in anaerobic digestion can be achieved by implementing pectinolytic enzymes in conjunction with a high-solids stackable digestor and a wet digestor. Recent studies have shown that enzymes can increase the amount of methane produced by 158% and reduce the digestion time by up to 40 days. The multi-digester system supports the digestion of molecules that breakdown in various conditions. Acid gases are stripped from the biogas using the amine process, while the sulfur recovery stage converts these stripped gases into elemental sulfur to avoid their release into the atmosphere. The membrane train includes a cascading series of two membranes that separate out remaining carbon dioxide (CO2) from the biogas to produce a pipeline-grade renewable natural gas.  

Students:

  • Priya Shrestha
  • Sarah From
  • Kneev Sharma
  • Jonathan Taylor
  • Shreel Pillai