Limbah cair kelapa sawit dapat diproses menggunakan teknologi anaerobic digestionuntuk menghasilkan biogas. Biogas yang dihasilkan dari proses anaerobic digestionmasih memiliki kandungan gas pengotor yang cukup tinggi, yaitu CO2 sebesar 30% –45% dan H2S sekitar 1500 - 3000 ppm. Pada penelitian ini akan dilakukan studi kelayakanpembangunan anaerobic digestion dari limbah kelapa sawit dan fasilitas pemurnianbiogas dengan tiga pilihan teknologi yaitu water scrubbing, amine scrubbing danpemisahan menggunakan membran. Kajian teknologi dilakukan dengan melakukansimulasi menggunakan software Aspen Plus dengan laju alir biogas 0,8 MMCFD dandengan memvariasikan kandungan gas metana dalam biogas sebesar 50% dan 65% fraksimol. Target produk biometana mengandung CH4 > 95%, CO2 < 5%, H2S < 10 ppm dankandungan air < 10 lb/MMscf. Biaya investasi dan operasi untuk fasilitas anaerobicdigestion menggunakan data proyek biogas terdahulu yang telah terdaftar pada proyekCDM (Clean Development Mechanism) UNFCCC di Indonesia. Sedangkan biayainvestasi untuk fasilitas pemurnian biogas didapatkan dari hasil simulasi menggunakansoftware Aspen Plus. Kajian keekonomian dilakukan untuk menghitung harga jual gasbiometana dengan nilai pengembalian investasi yang diharapkan sebesar 12%. Tingkatkemurnian biometana dari fasilitas water scrubbing mencapai 97,38%, dari fasilitasamine scrubbing mencapai 99,93% dan dari fasilitas membran mencapai 95,04%. Darihasil simulasi dan perhitungan, didapatkan harga jual biometana paling rendah adalahsebesar $13,06/MMBtu dengan menggunakan teknologi amine scrubbing.

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Palm oil Mill Effluent can be processed using anaerobic digestion technology to produce

biogas. Biogas produced from the anaerobic digestion process still contains a high amount

of impurity gases, namely CO2 of 30% - 45% and H2S of around 1500 - 3000 ppm. This

research will conduct a feasibility study on developing a biogas upgrading facility from

an anaerobic digestion process of palm oil mill effluent with three technological options,

water scrubbing, amine scrubbing and membranes. The technical study was carried out

using Aspen Plus software with a biogas flow rate of 0.8 MMCFD and varying the

methane content in biogas by 50% and 65% mole fraction. The target biomethane product

contains CH4 > 95%, CO2 < 5%, H2S < 10 ppm and water content <10 lb/MMscf. The

investment and operating costs for anaerobic digestion facilities use data from previous

biogas projects that have been registered in the UNFCCC CDM (Clean Development

Mechanism) project in Indonesia. Meanwhile, the biogas upgrading facility's investment

cost is obtained from the simulation results using Aspen Plus software. An economic

study was conducted to calculate the gas price of biomethane with an expected internal

rate of return of 12%. The purity level of biomethane from water scrubbing facilities

reached 97.38%, from amine scrubbing facilities reached 99.93%, and from membrane

facilities reached 95.04%. From the simulation and calculation result, the lowest gas price

of biomethane was $ 13.06/MMBtu using amine scrubbing technology.