Potential of urine as an activator in the decomposition of biodegradable urban wastes

Poor sanitation and water pollution are among the problems that plague the environment. A way to address this is through ecologically and economically sustainable sanitation systems or EcoSan. EcoSan seeks to prevent pollution and disease caused by human wastes. Treating these wastes as recoverable and recyclable materials reduces waste disposal problems. In line with this, Ngilangil (DMMMSU) studied the potential of urine as an activator in the decomposition of biodegradable urban wastes. Specifically, it determined the number of days to decompose urban wastes and the nutrient composition of the compost treated with urine. Activities were conducted at the Material Recovery Facility of the North La Union Campus of DMMMSU in Bacnotan, La Union from June to October 2005. The researcher used 2 kg sawdust and 1 L urine for each of the 2 kg household wastes, 2 kg market wastes, and 2 kg food wastes. These were compared with treatments, which have the same amount of substrates but without urine. Raw materials were piled in 200-L plastic drums with perforated PVC pipe placed as aerator. All prepared substrates were added with Fish Amino Acid (FAA) - a mixture of fish trash and crude sugar fermented for 2 weeks. The drums were covered with plastics tied with strings. The compost pile was turned every 2 days to enhance aeration. Findings of the study revealed the following: Household wastes with urine (HW1) decomposed at 43 days - 10 days shorter than that of HW without urine (HWo). At 43 days, both treatments attained a temperature of 29.7 deg C. Market wastes with urine (MW1) decomposed at 42 days at 31 deg C while MW without urine (MWo) had longer decomposition period of 48 days at 31.3 deg C. Food wastes with urine (FW1) decomposed at 42 days at 30.3 deg C. This was 6 days shorter than FW without urine (FWo), which decomposed at 48 days and 31.2 deg C. FW1 had the highest percent total N of 0.39. However, HW1 obtained the highest percent total P and K values at 0.017 and 0.458, respectively. The different treatments used had comparable percent total OM and pH values. The pH values showed that the compost products had slight acidity. The matured compost added with urine posted high carbon/nitrogen (C:N). The ideal C/N ratio for most compost microorganisms is 25:1. Materials too high in carbon make composting inefficient and will take longer time to decompose. Materials too high in nitrogen will likely release the excess smelly ammonia gas. The researcher recommended a comparative study using other activators in the same treatments to find out the urine's effectiveness. The compost products from the different treatments should be tested in plants to determine the urine's efficiency as a mineral fertilizer.