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Alternative methodologies for the reduction of greenhouse gas (GHG) emissions from crude palm oil (CPO) production by a wet extraction mill in Thailand were developed. The production of 1 t of CPO from mills with biogas capture (four mills) and without biogas capture (two mills) in 2010 produced GHG emissions of 935 kg carbon dioxide equivalent (CO2eq), on average. Wastewater treatment plants with and without biogas capture produced GHG emissions of 64 and 47% of total GHG emission, respectively. The rest of the emissions mostly originated from the acquisition of fresh fruit bunches. The establishment of a biogas recovery system must be the first step in the reduction of GHG emissions. It could reduce GHG emissions by 373 kgCO2eq/t of CPO. The main source of GHG emission of 163 kgCO2eq/t of CPO from the mills with biogas capture was the open pond used for cooling of wastewater before it enters the biogas recovery system. The reduction of GHG emissions could be accomplished by (i) using a wastewater-dispersed unit for cooling, (ii) using a covered pond, (iii) enhancing the performance of the biogas recovery system, and (iv) changing the stabilization pond to an aerated lagoon. By using options i-iv, reductions of GHG emissions of 216, 208, 92.2, and 87.6 kgCO2eq/t of CPO, respectively, can be achieved.

The present research aims to examine the coagulation process enhancement for dissolved organic matter (DOM) and The present research aims to examine the coagulation process enhancement for dissolved organic matter (DOM) and trihalomethane formatation potential (THMFP) removal from a raw water supply with low turbidity and specific ultraviolet absorption (SUVA). Coagulation conditions were optimized using polyaluminum chloride (PACl), PACl with dry cationic polymer (polymer), and PACl with polymer and powder activated carbon (PAC). DOM was measured in terms of dissolved organic carbon (DOC) and ultraviolet absorption at a wavelength of 254 nm (UV-254). Results show that the optimal condition for PACl, PACl and polymer, and PACl with polymer and PAC coagulation were PACl 20 mg/L at pH 7, PACl 20 mg/L and polymer 0·1 mg/L, and PACl 20 mg/L with polymer 0·1 mg/L and PAC 10 mg/L, respectively. When the DOM contents in coagulated water were fractioned to be hydrophilic (HPI) and hydrophobic (HPO) groups, it was found that the coagulation process could effectively remove more DOC of HPO than DOC of HPI. The coagulation using PACl combined with polymer and PAC provided the highest level of DOC of HPI, DOC of HPO, Trihalomethane formation potential (THMFP) of HPI, and THMFP of HPO removal efficiencies and were shown to be 65%, 75%, 77%, and 79%, respectively.