Method and Apparatus for Reducing Organic Waste by Rotary Desiccation

Abstract

A machine is described that reduces landfill and compost waste streams by processing the waste at the site of generation. The process used, rotary desiccation, is fast, energy efficient, generates no greenhouse gasses and the end product is both sterile and suitable for immediate use as a pellet fuel or other biomass uses. The machine integrates a number of sub-components (grinder, de-waterer, desiccation drum, separation devices) in new and non-obvious ways that automatically process and sort organic wastes and contaminants with no intervention from operators and very little maintenance.

1 . Greater efficiency
 Over composting
 On-site processing, no transporting of waste with attendant petroleum use and emissions 
   Over extant desiccators
 Process air recycled: No vent to the outside, no heat wasted 
 Process independent of heat source: Electric, natural gas and steam heated versions are equally plausible and accommodated in the design 
 Pre-processor reduces particle size and removes up to 90% of the water prior to desiccation, reducing desiccation time (thus energy use) by more than half 
 Requires no process water (unlike traditional pulpers and grinder/compactors) 
   
     
     
         2 . Higher Speed: Process Time 10 to 15 hours (new material can be added at any time)
 Over composting
 Process Time: 90 days, must be turned every week. 
   Over extant desiccators
 Process Time: 18 to 24 hours (machine locks during processing, new material must wait for cycle to finish) 
   
     
     
         3 . No greenhouse gas generated
 Over composting
 CO 2  generated 
   Over landfill   
     
     
         4 . Ease of Use: Any invention must be easy and intuitive to use if it is to be accepted and used. This Invention has deliberate design features to make it as “user friendly” as possible in commercial kitchens where many of the staff who will be using it are not technically sophisticated. Specifically:
 Continuous process (not batch processor): Can be used exactly like a dumpster: open the lid (hopper), dump in waste, close lid (hopper). No machine operation to think about. 
 Accepts all compostable waste (including paper waste and “compostable” plastics): No pre-sorting required 
 Tolerates non-compostable material: silverware, glassware, plastic film, etc. that unavoidably get tossed out with the waste. These will not jam machine and are automatically sorted out 
 Feed Hopper Capacity: 1 cu. ft. (˜7 gallons): many kitchens use 5 gallon buckets for waste disposal since that's close to the OHSA 40 lb carry limit (5 gallons of high-water-content waste weighs ˜35 lbs). The hopper is sized to accept a full 5 gallon bucket with some margin 
 Feed Hopper Height: Ergonomically placed at 36″ from the floor to avoid stress injuries from the high-lifts associated with standard dumpsters 
 
     
     
         5 . Easily adapted to greater automation:
 For users with waste receptacles larger than a 5-gallon bucket, the Feed Hopper ( 7 ) can be replaced with an interface for a commercial dump lift that can accommodate up to a standard 32 gallon receptacle.   Since the unit can accept waste continuously and randomly, it can be interfaced to a “scraping station” in a commercial kitchen with a short external conveyor.