• 1 Civil Engineering Programme, Faculty of Engineering, Universiti Teknologi Brunei, Tungku Highway, Gadong BE1410, Brunei Darussalam
  • 2 Department of Environmental Engineering, Universiti Tunku Abdul Rahman, 31900 Kampar, Perak, Malaysia.. Electronic address:
  • 3 Department of Environmental Engineering, Universiti Tunku Abdul Rahman, 31900 Kampar, Perak, Malaysia
  • 4 Department of Civil and Environmental Engineering, Universiti Teknologi PETRONAS, 32610 Bandar Seri Iskandar, Perak, Malaysia
  • 5 Environmental Engineering Section, Department of Civil Engineering, Aligarh Muslim University, Aligarh 202002, India
  • 6 Department of Physical and Mathematical Science, Universiti Tunku Abdul Rahman, 31900 Kampar, Perak, Malaysia
Sci Total Environ, 2020 Jun 20;722:137833.
PMID: 32199372 DOI: 10.1016/j.scitotenv.2020.137833


Palm oil mill effluent (POME) is a highly polluted wastewater that consists of a high organic content of 4-5% total solids; a potential renewable energy source. A waste to energy study was conducted to improve biogas production using POME as substrate by ultrasonication pretreatment at mesophilic temperatures. The effect of temperature on the specific growth rate of anaerobes and methanogenic activity was investigated. Five sets of assays were carried out at operating temperatures between 25 °C and 45 °C. Each set consisted of two experiments using identical anaerobic sequencing batch reactors (AnSBR); fed with raw POME (control) and sonicated POME, respectively. The ultrasonication was set at 16.2 min ultrasonication time and 0.88 W mL-1 ultrasonication density with substrate total solids concentration of 6% (w/v). At 25 °C, biogas production rate and organic matter removal exhibited lowest values for both reactors. The maximum organic degradation was 96% from AnSBR operated at 30 °C fed with sonicated POME and 91% from AnSBR operated at 35 °C fed with unsonicated POME. In addition, the methane yield from AnSBR operated at 30 °C was enhanced by 21.5% after ultrasonication pretreatment. A few normality tests and a t-test were carried out. Both tests indicated that the residuals of the experimental data were normality distributed with mean equals to zero. The results demonstrated that ultrasonication treatment was a promising pretreatment to positively affect the organic degradation and biogas production rates at 30-35 °C.

* Title and MeSH Headings from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.