An on-site organic waste processing unit for commercial food producers

Grant: $7,860

Project aim

There is a lack of affordable on-site organic waste stabilisation equipment for small to mid-size operators. The project will develop low cost functional hardware for organic waste stabilisation in situ by commercial kitchens and food producers. This will provide an effective way to remove organic waste from the waste stream immediately. The project is aimed at filling the gap between household sized composting or worm farming, and large centralised collections on a municipal scale.

Project methodology

1. Constructed an inexpensive medium scale prototype (120 - 240 litres per day) worm-based processing system. This design operates on a continuous flow principle, with food constantly being added to the top and the few worm castings formed dropping into the catch at the bottom for automatic bagging. The castings can also be dropped into the top again with the food. Eventually all of the food content and castings are converted to carbon dioxide gas and water vapour. This type of bed doesn't usually require extra watering and there is no leachate.
2. Operated the prototype system for a trial period to determine and document the operating parameters.
3. Improved the design of the prototype.
4. Prepared an article suitable for publication.
5. Made design commercially available.

Project outcomes

1. Operation of the prototype has demonstrated that it is an effective system in terms of low labour requirements, low cost, minimum space requirements and excellent operational performance.
2. The prototype has been displayed to many visitors, and information on the system has been disseminated at a conference.
3. The unit will act as an example for schools, institutions, commercial kitchens, cafes and restaurants.

Key factors contributing to project success

1. The airtight lid reduces odour emission. As long as aerobic conditions are maintained, there is almost complete conversion of the food into carbon dioxide and water vapour;
2. The mesh floor with catcher underneath allows the few worm castings that drop through to be collected and also aids in the system remaining aerobic;
3. The continuous flow system is self-contained and sustainable and does not have any output to be managed, such as excess worm population or worm castings;
4. A break of a week in feeding does not cause problems;
5. Onions and citrus can be used in the system;
6. The system operates best under 30 degrees celcius. An air vent can keep the system temperature down in summer and be closed in winter to retain the warmth.

Information material developed

Report, 'The Continuous Flow Worm Bed for On-site Organic Waste Management'

Related projects

• 97_016 - Green Waste Reprocessing in Schools
• 97_071 - Home Worm Factory Trial
• 97_128 - Education in Domestic Waste Reduction - a Demonstration Worm Farm and Composting Facility
• 97_195 - Worm Farm Development
• 97_205 - An On site Organic Waste Processing Unit for Commercial Food Producers
• 98_031 - Waste Food Collection from Restaurants, Cafes and Supermarkets for Processing in a Worm Farm
• 98_038 - Grass Roots Food and Green Waste Avoidance Program
• 98_143 - Trial of an Industrial Capacity Worm Bin
• 98_203 - BioGreen Castings - Assessing the Merits of Vermiculture in Biosolid Management

Contacts

James Kater
Phone: (02) 9557 3487
Fax: (02) 9557 5514
jkater@ozemail.com.au
 

Community Waste Reduction Grants Co-ordinator
Environment Protection Authority
Phone: (02) 9995 5639
http://www.epa.nsw.gov.au/waste/