Organic Waste Management

Johnston, RI Anaerobic Digester Information

Anaerobic digestion is an alternative option for recycling food waste. The completely enclosed digester contains bacteria that break down the organic matter and release methane as a product. This methane is siphoned off and convert-ed into electricity which is then sold to National Grid. The only other end by-product of the process is usable compost. Anaerobic digestion uses proven technology widely used in Europe and increasing in popularity in the U.S.
Johnston Digestor Construction
Anaerobic Digestor pictured under construction in Johnston, RI

Johnston Digester Fast Facts

Digester Size: 3.2 megawatts
Opening Date: January 2016
Total Capacity: 300 Tons per day
Accepted Contamination Level: 15%
Address: 293-303 Scituate Ave
Johnston, RI 02919
Food Residuals


What materials can be anaerobically digested?

Acceptable Organic Materials
    Highly Desirable:
  • Animal Fats and Meat Renderings
  • Bakery Waste
  • Breads
  • Brewery Waste
  • Meats, Sausages, Fish
  • Pasta, Flour, Grains
  • Pet Food
  • Produce
  • Restaurant Waste
    Less Desirable:
  • Coffee Grinds/Tea
  • Dairy Products
  • Eggs
  • Fresh Cut Flowers
  • Grease
  • Seaweed
  • Vegetable Oils

  • Other Organic Waste as approved
Undesirable Materials / Out-Throws
Standard Acceptable limits Combined <15%;
Undesirables above 15% must be approved
  • Aluminum
  • Cardboard
  • Clay Pots
  • Fabrics
  • Leaves
  • Metal
  • Napkins
  • Paper
  • Paper Towels
  • Plastic Bags
  • Silage
  • Stall Wastes
  • Toilet Tissue

  • Other waste as may be described from time to time
Unacceptable Materials / Prohibited
At any levels these items can damage the equipment and/or process
  • Batteries
  • Chemicals
  • Construction Waste
  • Cut Hair
  • Dyes
  • Fertilizers
  • Glass
  • Human Waste
  • Medicine
  • Motor Oil
  • Pet Litter
  • Rocks, Sand
  • Styrofoam
  • Toxic Substances
  • Treated Wood

  • Other non-organic waste detrimental to the operation as may be described from time to time

Organic Waste Management reserves the right to make changes to this list at any time