Strategies for improving biogas production of palm oil mill effluent (POME) anaerobic digestion: A critical review

Malaysia is one of the largest palm oil producers worldwide and its most abundant waste, palm oil mill effluent (POME), can be used as a feedstock to produce methane. Anaerobic digestion is ideal for treating POME in methane production due to its tolerance to high-strength chemical oxygen demand (COD). In this work, we compared the culture conditions during the start-up of anaerobic digestion of acidified POME between thermophilic (55 °C) and mesophilic (37 °C) temperatures. The pH of the digester was maintained throughout the experiment at 7.30 ± 0.2 in a working volume of 1000 mL. This study revealed that the thermophilic temperature stabilized faster on the 44th day compared to the 52nd day for the mesophilic temperature. Furthermore, the thermophilic temperature indicated higher biogas production at 0.60 L- CH 4 /L·d compared to the mesophilic temperature at 0.26 L- CH 4 /L·d. Results from this study were consistent with the COD removal of thermophilic temperature which was also higher than the mesophilic temperature.

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Biogas production from palm oil mill effluent and empty fruit bunches by coupled liquid and solid-state anaerobic digestion

Bioresource Technology ◽

10.1016/j.biortech.2019.122304 ◽

2020 ◽

Vol 296 ◽

pp. 122304 ◽

Cited By ~ 12

Author(s):

Wantanasak Suksong ◽

Wisarut Tukanghan ◽

Kanathip Promnuan ◽

Prawit Kongjan ◽

Alissara Reungsang ◽

...

Keyword(s):

Anaerobic Digestion ◽

Solid State ◽

Palm Oil ◽

Biogas Production ◽

Palm Oil Mill Effluent ◽

Empty Fruit Bunches ◽

Palm Oil Mill

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Inoculum Selection and Micro-Aeration for Biogas Production in Two-Stage Anaerobic Digestion of Palm Oil Mill Effluent (POME)

Jurnal Bahan Alam Terbarukan ◽

10.15294/jbat.v8i1.16318 ◽

2019 ◽

Vol 8 (1) ◽

pp. 14-21

Author(s):

Sri Ismiyati Damayanti ◽

Dian Fitriani Astiti ◽

Chandra Wahyu Purnomo ◽

Sarto Sarto ◽

Wiratni Budhijanto

Keyword(s):

Anaerobic Digestion ◽

Palm Oil ◽

Volatile Fatty Acids ◽

Biogas Production ◽

Liquid Waste ◽

Palm Oil Mill Effluent ◽

Cow Manure ◽

Two Stage ◽

Second Stage ◽

Palm Oil Mill

Two-stage anaerobic fluidized bed is an innovation in anaerobic digestion technology intended to handle liquid waste with high organic loading and complex substrate. The process is based on separation between acidogenic/acetogenic and methanogenic processes. The first stage is anaerobic process to convert substrate (represented as soluble chemical oxygen demand/sCOD) into volatile fatty acids (VFA). The second stage is methanogenic process to convert VFA into biogas. This study aimed to separate acidogenic/acetogenic and methanogenic processes by means of limited injection of air (micro-aeration) and inoculum selection. Micro-aeration was introduced in acidogenic/acetogenic stage because the relevant microbes were facultative so that the obligate anaerobic methanogens will be suppressed. On the other hand, the methanogenic reactor was kept completely anaerobic to ensure methanogenic dominance over acidogenic/acetogenic ones. Two sources of inoculums were used in this study, i.e. anaerobically digested biodiesel waste and anaerobically digested cow manure. Both inoculums were taken from active biogas reactor treating biodiesel waste and cow manure, respectively. Experiments were run in batch reactors treating palm oil mill effluent (POME) as the substrate for the acidogenic/acetogenic reactor. After the reaction in the first stage reached the minimum substrate concentration, the content of the reactor was used as the substrate for the methanogenic reactor as the second stage. Routine measurements were taken for sCOD and VFA concentrations, biogas production, and methane concentration in the biogas. Results confirmed that micro-aeration maintained good performance of acidogenic/acetogenic process, which was indicated by peaks in VFA accumulation, while suppressing methanogenic activities as no methane produced in this stage. Digested biodiesel waste was superior inoculum to be compared to digested cow manure with respect to sCOD removal. In the methanogenic stage, digested biodiesel waste also performed better as inoculum as it led to higher VFA conversion, higher biogas production rate, and higher methane content in the biogas.

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MODELING OF BATCH AND CONTINUOUS ANAEROBIC DIGESTION OF PALM OIL MILL EFFLUENT: THE EFFECT OF WASTEWATER-SLUDGE RATIO

Jurnal Teknologi ◽

10.11113/jt.v78.8649 ◽

2016 ◽

Vol 78 (5-6) ◽

Author(s):

Hathaikarn Thongpan ◽

Rachadaporn Thongnan ◽

Nirattisai Rakmak ◽

Chairat Siripatana

Keyword(s):

Anaerobic Digestion ◽

Palm Oil ◽

Production Efficiency ◽

Biogas Production ◽

Wastewater Sludge ◽

Palm Oil Mill Effluent ◽

Lag Phase ◽

Type Model ◽

Initial Ph ◽

Palm Oil Mill

In this work, both models for batch and continuous anaerobic digestion of palm oil mill effluent were developed based on Monod’s kinetics. Then the authors attempt to understand the effect of wastewater-sludge (WW:S) ratio on the biogas production efficiency in batch digesters. The experiments were carried out at a controlled temperature of 35±0.5 °C. Two series of the experiment were conducted. In the first series, the wastewater-sludge ratios covered 1:1 (add sodium bi-carbonate), 1:1, 1:2 and 2:1. It was found that the ratio of 1:2 gave the highest biogas producing efficiency followed by the ratio 1:1 (add sodium bi-carbonate). At 1:1 ratio, sodium bi-carbonate addition was required to start anaerobic digestion at a workable pH range whereas at 1:2 ratio the initial pH is in the workable range without the need of its addition. However, at the ratio of 2:1 the starting pH was too low to adjust pH economically by adding sodium bi-carbonate. The second series was to confine experiments to a narrower ratio range, namely: 1:1 (add sodium bi-carbonate), 1:1.5, 1:2, 1:2.5. In both sets of experiment, the ratio 1:2 gave the best biogas production potential of 76.62 and 78.52 ml of biogas/g COD removed respectively. In all treatments, the process was able to remove more than 80% of wastewater initial COD. The modified Gompertz equation was used to estimate the maximum specific biogas production rate (MBPR or Rm/S0). It was also found that the ratio of 1:2 gave the best MBPR in both experimental series (26.87 ml biogas/g COD-day). A modified Monod-type Model was also developed to describe the microbial growth, substrate consumption and biogas production in continuous operation. In general, sludge recycle provided active biomass which can use the substrate in the wastewater instantly without significant lag phase or delay. Furthermore, continuous-flow model developed, with parameters estimated from batch experiments, predicted the experimental kinetics of the actual continuous experiments satisfactory.

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Improved anaerobic digestion of palm oil mill effluent and biogas production by ultrasonication pretreatment

The Science of The Total Environment ◽

10.1016/j.scitotenv.2020.137833 ◽

2020 ◽

Vol 722 ◽

pp. 137833 ◽

Cited By ~ 5

Author(s):

Mohamed Hasnain Isa ◽

Lai-Peng Wong ◽

Mohammed J.K. Bashir ◽

Nasir Shafiq ◽

Shamsul Rahman Mohamed Kutty ◽

...

Keyword(s):

Anaerobic Digestion ◽

Palm Oil ◽

Biogas Production ◽

Palm Oil Mill Effluent ◽

Palm Oil Mill

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Peningkatan Produksi Biogas dari Palm Oil Mill Effluent (POME) dengan Fluidisasi Media Zeolit Termodifikasi pada Sistem Batch

Jurnal Rekayasa Proses ◽

10.22146/jrekpros.56133 ◽

2020 ◽

Vol 14 (1) ◽

Author(s):

Firda Mahira Alfiata Chusna ◽

Melly Mellyanawaty ◽

Estin Nofiyanti

Keyword(s):

Anaerobic Digestion ◽

Chemical Oxygen Demand ◽

Trace Element ◽

Palm Oil ◽

Biogas Production ◽

Oxygen Demand ◽

Organic Content ◽

Palm Oil Mill Effluent ◽

Soluble Chemical Oxygen Demand ◽

Palm Oil Mill

The production of crude palm oil (CPO) in Indonesia tends to increase over time. Palm oil mill effluent (POME) is the wastewater generated from the palm oil mill process with high organic content. POME is a potential source for anaerobic digestion due to its high organic content. The challenge of POME treatment using an anaerobic process is to enhance biogas production with high soluble chemical oxygen demand (sCOD) removal efficiency. The purpose of this study was to evaluate the effect of selected trace elements addition onto zeolite as immobilization media to the anaerobic digestion of POME in a fluidized batch system. Natural zeolite was used as the medium to immobilize microorganisms in an anaerobic fluidized bed reactor (AFBR). This study used three trace elements impregnated to natural zeolites, i.e. Ni2+, Zn2+, Mg2+. The result shows that Ni2+ and Zn2+ improve the methanogenesis process, prevent the accumulation of VFA as an intermediate product and increase the methane (biogas) production. Meanwhile, Mg2+ only reduced sCOD significantly but it did not affect methane production. Fluidization enhanced the performance of the POME anaerobic digestion process. The fluidization provide a positive effect to enhance biogas production and sCOD removal. The efficiency of sCOD removal in the entire reactors were 80.82%; 81.77%; 75.89% for AFBR-Ni; AFBR-Zn and AFBR-control respectively. The total volume of methane produced by the three AFBR were 163,04; 136,42; 62,79 (in ml CH4 / g sCOD) for AFBR-Ni; AFBR-Zn and AFBR-control, respectively. A B S T R A KProduksi crude palm oil (CPO) di Indonesia cenderung meningkat seiring bertambahnya waktu. Palm oil mill effluent (POME) adalah air limbah yang dihasilkan dari proses penggilingan kelapa sawit dengan kandungan organik yang tinggi. Tantangan dalam mengolah POME menggunakan proses peruraian anaerobik adalah untuk meningkatkan produksi biogas dengan efisiensi penurunan soluble chemical oxygen demand (sCOD) yang tinggi. Tujuan dari penelitian ini adalah mengevaluasi pengaruh penambahan trace element terseleksi pada media imobilisasi zeolit terhadap proses peruraian anaerobik limbah POME dengan sistem batch terfluidisasi. Zeolit alam berperan sebagai media imobilisasi mikroorganisme dalam anaerobic fluidized bed reactor (AFBR). Penelitian ini menggunakan tiga trace element yang diimpregnasikan pada zeolit alam yaitu Ni2+, Zn2+, Mg2+. Hasil penelitian menunjukkan bahwa Ni2+ dan Zn2+ sebagai trace element dapat meningkatkan proses metanogenesis dan mencegah akumulasi VFA sebagai produk antara serta meningkatkan produksi gas metana (biogas). Mg2+ sebagai trace element menurunkan sCOD dengan cukup signifikan namun tidak diimbangi dengan banyaknya metana yang dihasilkan. Fluidisasi meningkatkan performa dari proses peruraian anaerobik POME. Proses fluidisasi memberi pengaruh positif dalam meningkatkan produksi biogas dan soluble chemical oxygen demand (sCOD) removal. Nilai sCOD removal yaitu 80,82%; 81,77%; 75,89% berturut-turut untuk AFBR-Ni; AFBR-Zn dan AFBR-kontrol. Total volume metana yang dihasilkan oleh ketiga AFBR yaitu 163,04; 136,42; 62,79 (dalam ml CH4 / g sCOD) berturut-turut untuk AFBR-Ni; AFBR-Zn dan AFBR-kontrol.

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Co-digestion of palm oil mill effluent for enhanced biogas production in a solar assisted bioreactor: Supplementation with ammonium bicarbonate

The Science of The Total Environment ◽

10.1016/j.scitotenv.2019.136095 ◽

2020 ◽

Vol 706 ◽

pp. 136095 ◽

Cited By ~ 4

Author(s):

B.K. Zaied ◽

Mohd Nasrullah ◽

Md. Nurul Islam Siddique ◽

A.W. Zularisam ◽

Lakhveer Singh ◽

...

Keyword(s):

Palm Oil ◽

Biogas Production ◽

Ammonium Bicarbonate ◽

Palm Oil Mill Effluent ◽

Palm Oil Mill

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Performance of Anaerobic Digestion of Acidified Palm Oil Mill Effluent under Various Organic Loading Rates and Temperatures

Water ◽

10.3390/w12092432 ◽

2020 ◽

Vol 12 (9) ◽

pp. 2432

Author(s):

Muhammad Arif Fikri Hamzah ◽

Peer Mohamed Abdul ◽

Safa Senan Mahmod ◽

Azratul Madihah Azahar ◽

Jamaliah Md. Jahim

Keyword(s):

Anaerobic Digestion ◽

Palm Oil ◽

Denaturing Gradient Gel Electrophoresis ◽

Oxygen Demand ◽

Microbial Community Analysis ◽

Palm Oil Mill Effluent ◽

Methane Formation ◽

Organic Loading ◽

Loading Rates ◽

Palm Oil Mill

This study compared the performance of thermophilic and mesophilic digesters of an anaerobic digestion system from palm oil mill effluent (POME), in which temperature is a key parameter that can greatly affect the performance of anaerobic digestion. The digesters were incubated at two distinct temperatures of 55 and 37 °C, and operated with varying organic loading rates (OLRs) of 2.4, 3.2, and 4.0 g COD/L.d by altering the chemical oxygen demand (COD) of acidified POME during feeding. The results indicated that the performance of anaerobic digestion increased as the OLR increased from 2.4 to 4.0 g COD/L.d. At the OLR of 4.0 g COD/L.d, the thermophilic condition showed the highest methane yield of 0.31 ± 0.01 L/g COD, accompanied by the highest COD removal and volatile solid reduction, which were found to be higher than the mesophilic condition. Microbial community analysis via denaturing gradient gel electrophoresis (DGGE) revealed that Methanothermobacter sp. emerges as the dominant microbe, which is known to utilize the carbon dioxide pathway with hydrogen acting as an electron donor for methane formation

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