Abstract: A use of calcium oxide-cement kiln dust (CaO-CKD) for anaerobic granulation of palm oil mill effluent. A process to produce biogas from palm oil mill effluent using calcium oxide-cement kiln dust (CaO-CKD) wherein steps include inoculating palm oil mill effluent sludge in a reactor, conducting anaerobic digestion on the sludge and conducting anaerobic granulation of palm oil mill effluent.

Abstract: The present invention discloses a method for use in treating palm oil mill effluent (POME). Said method comprising the steps of: treating the palm oil mill effluents with concentrated butyrate; introducing the treated palm oil mill effluents into a reaction tank (11) with loading rate of at least 1.5 g COD/L/d and at least 4 days of hydraulic retention time; and providing microorganism biomass in the reaction tank so that anaerobic degradation of the palm oil mill effluents treated with butyrate can be performed. Preferably, the optimum condition for degradation of the palm oil mill effluents in the reaction tank is at constant temperature 37° C. with pH value of approximately 6.5-7.5.