OARDC Compost Research Facilities

OARDC compost building
Compost Research Center     
The OARDC/OSU Compost Research Center, which is housed in the 5,000 square foot Bioproducts and Bioenergy Research Laboratory, enables pilot-scale composting of a wide range of feedstocks. The Center features two different fully instrumented bioreactor systems - one with eight 208-liter vessels and the other with eighteen 4-liter compost vessels. Both systems feature continuous online oxygen, carbon dioxide, temperature and gas flow rate measurement. Attached to the building is an area for research on the composting of animal mortalities, bio-filtration and other outside (but sheltered) research. Over 50 studies have been completed in the Center to date.

mission control

incubator 2 test barrels
The fans that supply air to the 208 l reactors can be operated in a high/low (approximately 0.9 or 0.3 l min-1 kg DM-1) thermostatically controlled (60o C, 1.5o C differential), continuous mode (continuously aerated), or in an on/off timer controlled intermittent mode. Pressure drops across orifice plates are used to calculate inlet air flow rates. The system records 4 temperatures, airflow rate, Oxygen uptake, CO2 evolution, NH3 and heat evolution every 10 minutes for each reactor. Studies on odors are done by condensing gases leaving the reactors and analyzing with GC/MS instrumentation.

incubator

The 4-liter vessels are supplied with air using compressed air regulated with flow restrictors. Data collection is similar to the 208-liter vessels. This system is used for pathogen fate, microbial ecology, and bioremediation studies. It can also be used to test materials to determine whether they meet definitions of compostability described in ASTM standards D6400 and D6868.

 

Hayden Hall Microbial Ecology Laboratory   

The Microbial Ecology Laboratory at Hayden Hall houses equipment for compost microbial community analysis. Methods used include DNA extraction, PCR, culturing, cloning and sequencing, TRFLP, TRFLP Fragsort and RFLP analyses.
Hayden Hall building Hayden Hall lab microbes

 

Commercial-scale Composting Site

The OARDC composting site is a full scale windrow composting facility featuring a concrete composting surface and a built in aeration system. A wetland treatment system is used to treat pad runoff. The concrete pad is 52 m x 53 m (170 ft x 175 ft) in size and has eight built in aeration ducts for supplying air to compost windrows up to 28 m (92') in length. Each duct is a 10 cm (4") PVC pipe buried 5 cm (2") below the surface of the pad. Eighty-six 1 cm (3/8") holes were drilled into the pipe on 25 cm (1') centers. Attached to each pipe is a 0.75 kw (1 hp) fan capable of delivering 6.37 m3/min (225 cfm) of air at 17.8 cm (7 inches) of water pressure. The fans are equipped with programmable timers which allow their intermittent operation for as little as 30 seconds in 1 hour up to continuous operation. Equipment available at the pad for mixing, moving material, and turning windrows includes a feed mixing wagon with a weighing load cell, a skid steer loader and a tractor-assisted, Aeromaster 120 windrow turner. The slope of the composting pad is 1%, with a catch basin located at the lower end. Runoff from the pad is filtered through a wood chip windrow, collected in a catch basin and then carried by a pipe to a 3-cell wetland. The design of the wetland was based on NRCS standards using a 25 year-24 hour storm event.
OARDC compost pad

 

OARDC turner

OARDC pad