BIOGAS PRODUCTION USING FISH GUTS AND RICE STRAW AS SUBSTRATE

Fish guts, one of the fish waste product on fish production and rice straw and one of the major source of biomass in the Philippines can be an organic material used for biogas production. This study utilized this waste through anaerobic digestion by evaluating the gas of each slurry mixture produced for a retention time of 30 days. This study also observed the behaviour of the slurry inside the digester using a batch type digester for the experimental set-up, temperature gauge and pressure gauge for the temperature and pressure, respectively. In measuring the volume produced of the substrate, Water Displacement Method was used. The displaced water from the gas holder indicated the amount of gas produced by the substrate. Biogas production using fish guts and mixed with rice straw was quite possible. A substrate with fish guts only attained 45.07L, the higher gas produced than the substrate with fish guts mixed with rice straw. It is also observed that if the temperature reaches 40-50C,the substrate will produce gas, however this only occur during Noon time or when it is not raining on that day. The acidity of both substrate mixture have the same behaviour, the final pH level reached about 6.85 for fish guts and 6.9 for fish guts mixed with rice straw. On the flammability of gas, it only changed the colour of the candle into bluish flame and on the end of the study, a sudden burst of flame occured on the substrate of pure fish guts.