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MEKARN Workshop 2009: Livestock, Climate Change and the Environment |
Livestock production in Thailand has been developed to commercial or large-scale farming systems during the last three decades. Especially, pig production could be found only in medium and large-scale farming systems. According to such production systems, the wastes become major problems to be solved by farmers. The best solution at present is by introducing biogas technology to reduce wastes and pollution from the farms. Biogas technology was introduced to Thailand since the 1950 in the dairy farms with floating gas-holder system. Later, various organizations such as Health Care Department, National Energy Institute and Department of Agricultural Extension promoted the biogas technology to the farmers by introducing floating gas-holder system and adapted Chinese fixed dome type. It was report in 1989 that more than 11,000 biogas digesters with 4-6 m3 size were constructed to reduce problems of livestock wastes and produce biogas for household use. During 1990-1995 biogas technology was developed under Thai-German Biogas Programme. The fixed dome type digester was introduced to dairy farms and small pig farms and the plug flow channel types digester to medium and large-scale pig farms. The simple low cost plastic biogas digester was lately introduced to smallholder farming system. From the survey in 1999-2000 it was found that at least 1,600 pig farms were classified as the potential farms in biogas production with 429,970 LSU and required a total of 849,940 m3 of biogas digesters, for dairy farms, at least 2,120 farms could be classified as potential biogas producing farms with 125,239 LSU and would required 250,478 m3 biogas digesters.