@article{scholars12996,
           title = {Improved anaerobic digestion of palm oil mill effluent and biogas production by ultrasonication pretreatment},
       publisher = {Elsevier B.V.},
         journal = {Science of the Total Environment},
          volume = {722},
            note = {cited By 35},
             doi = {10.1016/j.scitotenv.2020.137833},
            year = {2020},
            issn = {00489697},
          author = {Isa, M. H. and Wong, L.-P. and Bashir, M. J. K. and Shafiq, N. and Kutty, S. R. M. and Farooqi, I. H. and Lee, H. C.},
        abstract = {Palm oil mill effluent (POME) is a highly polluted wastewater that consists of a high organic content of 4{\^a}??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 {\^A}oC and 45 {\^A}oC. 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{\^a}??1 ultrasonication density with substrate total solids concentration of 6 (w/v). At 25 {\^A}oC, biogas production rate and organic matter removal exhibited lowest values for both reactors. The maximum organic degradation was 96 from AnSBR operated at 30 {\^A}oC fed with sonicated POME and 91 from AnSBR operated at 35 {\^A}oC fed with unsonicated POME. In addition, the methane yield from AnSBR operated at 30 {\^A}oC 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{\^a}??35 {\^A}oC. {\^A}{\copyright} 2018 Elsevier B.V.},
        keywords = {Batch reactors; Biogas; Effluents; Palm oil; Renewable energy resources; Substrates; Temperature; Ultrasonics, Anaerobic sequencing batch reactors; Biogas production rates; Mesophilic temperature; Organic matter removal; Palm oil mill effluents; Renewable energy source; Total solids concentrations; Ultrasonication pretreatment, Anaerobic digestion, biogas; methane; organic matter; palm oil; biofuel, anaerobic digestion; anoxic conditions; biogas; concentration (composition); effluent; essential oil; ultrasonics; wastewater treatment, anaerobic digestion; Article; biofuel production; concentration (parameter); controlled study; degradation; effluent; growth rate; mesophilic temperature; methanogenesis; nonhuman; palm oil mill effluent; priority journal; solid; temperature; ultrasonication; ultrasound; anaerobic growth; bioreactor; industrial waste, Anaerobiosis; Biofuels; Bioreactors; Industrial Waste; Methane; Palm Oil},
             url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85081693828&doi=10.1016\%2fj.scitotenv.2020.137833&partnerID=40&md5=69c7bb341dc8c6ace2f64750a62f55bc}
}