PEMBUATAN GAS BIO DARI BEBERAPA MACAM LIMBAH BIOMASSA PADAT DENGAN CARA "BATCH CULTURE"

A laboratory experiment on biogas generation using solid waste in a batch culture under Thermophillic condition was conducted at the Forest Products Research and Development Centre, Bogor. The solid waste used in the experiment were rice straw, water hyacinth (Eichornia crassipes Mart. Solms) and rubber wood (Hevea braziliensis) sawdust. Fermentation condition for biogas production was kept constant under temperature of 53°C for 8 days. Inoculumn used for fermentation was residue from the experiment of organic municipal solid waste fermentation. The raw material used in this experiment consisted of mixture of 73 gram rice straw and 27 gram water, 70 gram rice straw and 30 gram water hyacinth, 38 gram rubber wood sawdust and 62 gram water, 36,25 gram rubber wood sawdust and 63,75 water hyacinth. To each mixture was added 900 gram of starter with dry matter content 28%. Each substrate sample was then placed in a 1,5 littre digester. The result of the experiment indicates that the highest production of biogas and methane were produced from rice straw substrate (0,43 littre of biogas and 0,21 littre of methane per gram of straw respectively), and the efficiency of biogas produced was 75%. The total calorific value of biogas produced was lower than that obtained from direct burning of rice straw. Although the calorific value of biogas is relatively low, its burning quality is better compared with direct burning. Besides that, the residue from fermentation process could be utilized as organic fertilizer and mushroom media