Gemidan Ecogi A/S: Pre-treatment of Food Waste for Anaerobic Digestion 

Gemidan Ecogi A/S, which develops technologies that treat and recycle food waste from households, businesses, and industry, operates three food-waste pre-treatment systems in Denmark. In total, these systems annually treat almost 100,000 tons of food waste (which would otherwise decompose and produce methane in a landfill) to produce 150,000 tons of a high-quality pulp (“bio-pulp”) for centralized anaerobic digester facilities. The facilities use the bio-pulp to produce biogas energy and fertilizer.

The Gemidan Ecogi Pre-treatment Facility

The Gemidan Ecogi pre-treatment facility processes food waste from residential, commercial, institutional, and industrial sources. The process optimizes the use of organic residues in the food waste and captures more than 95 percent of the organic content in the feedstock. The facility accepts source-separated food waste and food waste packaged in plastic bags, glass bottles, metal cans, paper containers, and more. The facility’s separation system rejects undesired inorganic substances, resulting in a 99.9 percent pure bio-pulp. The purity level also carries through to the digestate, allowing the digestate to be used as an organic fertilizer for crop production. To meet the need for liquid during the wet-pulping process, the system uses rainwater, water from a wastewater treatment plant, or liquid iron as environmentally friendly sources. The Danish Environmental Technology Verification (ETV) program extensively analyzed this technology called Ecogi. ETV has certified the process and the quality of the produced bio-pulp.

Figure 1. A Standard Ecogi Facility

Pre-treatment Facility in Frederikshavn, Jutland, Denmark

Gemidan Ecogi’s newest pre-treatment facility, located in Frederikshavn, Jutland, Denmark, became fully operational in April 2019. Rainwater collected in an on-site lagoon provides an environmentally sustainable source of the water needed during the pre-treatment process. The facility currently processes 25,000 tons of food waste annually but will eventually reach a capacity of 50,000 tons of food waste per year.

Figure 2. The Jutland Ecogi facility

Watch the video below to learn more about the facility:

Future Developments

Gemidan Ecogi has several food-waste pre-treatment systems that are slated to begin development and construction in 2020. With plans to expand their services beyond Denmark, Gemidan Ecogi is working to develop pre-treatment facilities in the United States, Poland, Korea, Australia, and India.

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