EFFECT OF TOTAL SOLID CONTENT TO BIOGAS PRODUCTION RATE FROM VINASSE (RESEARCH NOTE)

Vinasse that has high COD and total solid content is bottom of distillation from unit of bioethanol production Vinasse treatment using anaerobic digestion produced biogas. This research used anaerobic digester-laboratory scale at room temperature and batch system. The purpose of this research was investigation the effect of total solid content to biogas production rate from vinasse, pH profil and COD removal. Initial pH for all variables were adjusted 7 by using NaOH. The result showed that vinasse:water ratio of 1:3 (TS 7.015±0.007%) produced the most total biogas (37.409 mL/g COD) however vinasse:water ratio of 1:2 (TS 9.310±0.014%) had the biggest COD removal (23.580±0.532%) than others. Variables with TS more than 7.015±0.007% caused the overloading in the digester whereas below of that caused unstable in decomposition process. Total solid that was in high level indicated COD content of substrates in high level. The more of COD concentration of substrates in the digester made the more of COD removal after fermentation process at anaerobic condition.