Sompong Hirunmasuwan creator Hanaki, K. Chairperson Orth, H.M. Examination Committee Shin, Hang Sik Examination Committee Government of Japan Scholarship Donor text th Bangkok Asian Institute of Technology 1986 continuing eng 78 p. This study was conducted to investigate the performance of anaerobic attached growth reactors and the effect of temperature on it in term of constant temperature and fluctuated temperature of hot climate. Downflow stationary fixed film (DSFF) reactor was selected to represent the attached growth reactor. Three units were operated at different temperature; 24 and 35 ̕c reactors for constant temperature and out door reactor for fluctuated temperature. The 35 ̕c reactor was found to give the best results, more methane production was produced. The rapid attachment of bacteria on the film and the shortest time for acclimatization were observed under 35 ̕c operating temperature. In hot climate reactor, more biomass on the film was produced but methanogenic activity was not so hign. The results were compared with the conventional reactors. The DSFF showed better results, namely more gas production and methane content. However, longer time for acclimatization was necessary in DSFF reactors. A research study submitted in partial fulfillment of the requirements for the degree of Master of Science, School of Environment, Resources and Development Thesis (M.Sc.) - Asian Institute of Technology, 1986 Methane Asian Institute of Technology. http://203.159.5.9/ait-thesis/detail.php?q=B19641 http://203.159.5.9/ait-thesis/detail.php?q=B19641 011298 20260818154928.0