Effect of temperature on increasing biogas production from sugar industrial wastewater treatment by UASB process in pilot scale

An UASB system is anaerobic wastewater treatment that produces biogas with low operation cost. The main problem of this process is operating at temperatures below 25 degrees C which occurs in the winter season in Thailand. The aim of this work was to improve the efficiency of UASB system by mixing water condensate from electrical power plant with sugar influent before delivery to UASB reactor. The optimized temperature was investigated. The result shows the efficiency of VFA and COD removal was obtained ca. 92% with temperature at 29-40 degrees C. The maximum methane production (0.38 m(3)CH(4)/kg(COD)) has higher than design parameters about 27.51% at 40 degrees C. The methane production is reduced when the operating temperature is higher than 40 degrees C. Furthermore, the UASB could be considered for decreasing LPG cost in sugar refinery process. (C) 2016 The Authors. Published by Elsevier Ltd.