Determining the compost quality and efficiency using prototype horizontal composting aerator

In search of alternative process, Arazo et al. (MOSCAT) designed a prototype Horizontal Composting Aerator and compared the quality and efficiency of the generated compost with that of compost from the windrow method. The compost characteristics used for comparison were: bulk density and moisture content, pH level, nitrogen, phosphorus, and potassium contents, and biological characteristics like mungbean seed germination rate and weed seed population density. The study was conducted at the Ecological Park of MOSCAT from January to February 2006 using biodegradable solid wastes of MOSCAT and that of barangay [village] Poblacion, Claveria, Misamis Oriental [Philippines]. The biodegradable wastes were chopped into uniform particle size and piled for composting. Three replicate of 0.312 cu m were used both for static aerated composting and conventional window composting. In the prototype, air is introduced into the system through a suction propeller via the air inlet opening. The propeller suctions the air through the rotating motion of the tri-cup wind vane. The suction propeller forces air to pass through the four panel horizontal perforated pipes. The PVC screen is matted above the four parallel horizontal perforated pipes to prevent clogging on the perforations before the compost pile is mounted. Opposite the air inlet is the air outlet prototype with air filter to minimize odor that is produced during the decomposition. Findings of the study revealed the following: In both static aerated and conventional windrow composting, the compost produced was of good quality in terms of chemical characteristics such as pH, nitrogen, phosphorus, and potassium contents. Fair quality of compost resulted from both type of composting in terms of bulk density (porosity), moisture content, seed germination rate, and weed seed population density. Static Aerated was as efficient as the conventional windrow composting because there were no significant differences found in all parameters used in the study. However, in terms of labor and manpower requirement, using the prototype was better because it does not require regular manual turning of the pile. Also, it prevents a person from inhaling the odor caused by turning. The study recommended the use of Horizontal Composting Aerator in MOSCAT because of the good quality compost it produces and the ease of using it. Further segregation of solid wastes at source is recommended to avoid additional time in piling the materials. Further study is needed to improve the design and specifications of the prototype aerator. Other parameter for effective composting could be studied like color, texture, odor, carbon to nitrogen ratio, heavy metals, micro nutrient toxic compound, pathogens and root elongation.