Mixture ratios follow a central composite design that looks at combinations of three amounts of crab waste, sawdust, and wood chips. Two repetitions of the nine tanks will be run for three month periods. Samples are collected from the tanks during the initial setup, every two weeks for two months, and at the end of the third month when composting should be completed. Each tank is continuously monitored for temperature and the height of the compost in the tanks. An industrial scale is used to weigh each tank at each sampling interval and to record the loss of mass as composting occurs.
Tanks remain unmixed except for when samples are taken.
After sampling, the tanks are stirred with a compost aerator to mix and fill the holes where samples were taken to reduce channeling of the air through the compost. Samples are analyzed for percent carbon, total Kjeldahl nitrogen, and percent moisture. The data being collected will be statistically analyzed to develop a composting model and to determine the operating conditions that maximize composting efficiency and generate a stable and beneficial product. This research also provides information on the effects of varying bulking agent amounts on composting rates and product quality.