VERMICOMPOSTING Background Life Cycle Analysis Sean Brandt 23

VERMICOMPOSTING Background & Life Cycle Analysis Sean Brandt 23 April 2001

VERMICOMPOSTING DEFINITION Vermicomposting is the process of creating reasonably odorless compost by red worms feeding on microorganisms that degrade organic matter such as food waste. The worm castings (excrement) are nutrient-rich in usable forms for plants, and therefore make excellent fertilizer. ~ ~ Vermicompost System ~ ~ INPUT ~ OUTPUT

CLOSING THE LOOP microorganisms, worms plastic wood ~ ~ Vermicompost System ~ ~ INPUT ~ AGRICULTURE OUTPUT

VERMICOMPOSTING “SIZES” Small – individual, home Medium – small community or business Large – large community or industry

BASIC DESIGNS OF VERMICOMPOSTING Simple box Lateral movement Stackable tray Continuous flow

SMALL-SCALE VERMICOMPOSTING Personal Responsibility Input – personal/family food waste, some lawn and gardening waste System – small bin in basement, backyard Output – fertilizer for own garden Sustainable? – depends primarily on the bin, since “closed the loop” for some of own waste

SMALL-SCALE VERMICOMPOSTING Simple Box • Worm-A-Way (wormwoman) • 100% recycled plastic Simple Box • Little Worm Farm Kit • Wooden

SMALL-SCALE VERMICOMPOSTING Stackable tray • Wriggly Wranch • 100% recycled plastic Continuous flow • Earth Factory • Recycled plastic sides; steel frame; recycled redwood lid

SMALL-SCALE VERMICOMPOSTING Lateral movement • Wormaroo

MEDIUM-SCALE VERMICOMPOSTING (Small) Community Responsibility Input – community/business food waste, lawn and gardening waste System – large bins with different design needs than small bins Output – fertilizer for crops Sustainable? – again, depends primarily on the bin

MEDIUM-SCALE VERMICOMPOSTING Continuous Flow • EPM Institutional Bin

LARGE-SCALE VERMICOMPOSTING (Large) Community Responsibility Input – food waste, agricultural waste, paper waste, municipal solid waste System – large bins; troughs; ground surface overlay Output – fertilizer for crops Sustainable? – depends on the bin (sitespecific); also transportation cost gains

GENERIC DESCRIPTION OF VERMICOMPOSTING SYSTEMS Input – food waste, lawn and garden waste, paper waste, farm animal & human excrement System – wooden/plastic boxes, cement troughs, direct ground overlay; microorganisms and red worms on damp bedding Output – worm castings used as fertilizer (1/10 th tonnage, 30% increased yield), “tea” (separation of liquids and solids) Sustainable? – yes, for the most part (consider consumption and disposal); gains still possible in system design

GREEN CONSIDERATION OF VERMICOMPOSTING SYSTEMS INPUT = ORGANIC MATTER

GREEN CONSIDERATION OF VERMICOMPOSTING SYSTEMS SYSTEM = CONTAINER + “NATURE”

GREEN CONSIDERATION OF VERMICOMPOSTING SYSTEMS SYSTEM: CONTAINER Basic design considerations Size: 1 ft 3 space/lb “food” per week Temperature: 32 ºF < T < 85 ºF Ventilation/Drainage holes Green design considerations Recycled/Recyclable/Reusable Packaging (commercial, shipping) Source reduction: no container

GREEN CONSIDERATION OF VERMICOMPOSTING SYSTEMS SYSTEM: CONTAINER Wooden Bins reused wood no chemical sealants natural decomposition

GREEN CONSIDERATION OF VERMICOMPOSTING SYSTEMS SYSTEM: CONTAINER Plastic Bins % recycled content thermoplastic vs. thermoset plastic forming process packaging waste lasts for generations

GREEN CONSIDERATION OF VERMICOMPOSTING SYSTEMS SYSTEM: CONTAINER Ground Overlay no packaging! pile up different resources, let worms do work aesthetically pleasing if covered natural decomposition

GREEN CONSIDERATION OF VERMICOMPOSTING SYSTEMS SYSTEM: CONTAINER Cement Troughs recycled ash (from power generation) content transportation, packaging of cement crush & reuse as aggregate

GREEN CONSIDERATION OF VERMICOMPOSTING SYSTEMS SYSTEM: “NATURE” Native worm species Home-grown worms “Soil foodweb” Ecosystem food chain Bedding

GREEN CONSIDERATION OF VERMICOMPOSTING SYSTEMS OUTPUT = WORM CASTINGS

Summary and Conclusions Simple, effective Contributes to sustainability by reducing landfilling, closing loop from food chain Improvements can be made in containers and packaging (wood vs. thermoplastics vs. no container) Future – Tax on garbage, personal bins provided? Subsidy for compost? Another bin for curbside collection? Living machines?