Judul: Methane Emissions Reduction from Palm Oil Mill  Effluent through a Biogas Plant (Case Study: Tungkal Ulu Biogas Plant, Jambi)
Abstrak: Mayoritas industri kelapa sawit di Indonesia mengolah limbah cairnya atau Palm oil Mill Effluent (POME) menggunakan sistem kolam terbuka yang melepaskan gas metana dan berpotensi meningkatkan Gas Rumah Kaca (GRK). Salah satu upaya mencegah pelepasan gas metana dari sistem tersebut adalah pembangunan proyek methane recovery, melalui Pembangkit Listrik Tenaga Biogas (PLTBg). Proyek PLTBg mendukung target pemerintah dalam menurunkan emisi GRK dan menghasilkan energi terbarukan. Penelitian ini bertujuan untuk (1) mengestimasi potensi emisi GRK dari POME sebelum adanya proyek PLTBg, (2) mengestimasi reduksi emisi GRK dari POME setelah adanya proyek PLTBg, dan (3) menganalisis kelayakan finansial proyek PLTBg. Penelitian ini menggunakan metode Clean Development Mechanism (CDM) AMS III H dan analisis cashflow. Hasil penelitian menunjukkan bahwa PLTBg Tungkal Ulu mereduksi emisi GRK sekaligus menguntungkan perusahaan. Emisi sebelum adanya PLTBg yang diestimasi dari 106.267 m3 POME adalah 44.767,80 t CO2e. Potensi reduksi emisi setelah adanya PLTBg berkisar 66,64%-74,26% pada tahun 2021-2030. Pada kurun waktu tersebut, proyek PLTBg layak secara finansial pada harga CER rendah dan tinggi. Skenario CER rendah menghasilkan nilai NPV, BCR dan IRR sebesar Rp 18,55 miliar, 1,19 dan 11,46% sedangkan CER tinggi menghasilkan nilai NPV, BCR dan IRR sebesar Rp 19,65 miliar, 1,21 dan 11,69%., Most palm oil industries in Indonesia treat Palm Oil Mill Effluent (POME) by using an open lagoon system that releases methane gas emissions and potentially increases Greenhouse Gases (GHGs). Biogas plant, a methane recovery project, becomes one measures to reduce such emissions. Biogas Plant projects support the government's target in reducing GHGs emissions and produces renewable energy. By focusing on the Tungkal Ulu Biogas, this study aims to (1) estimate the potential GHGs emissions prior the implementation of biogas plant project, (2) estimate the GHGs emissions reduction after the project implementation, and (3) to analyze the financial feasibility of the project. This study employes Clean Development Mechanism (CDM) method (i.e. the AMS III H) and cashflow analysis. The results showed that Tungkal Ulu Biogas Plant project can reduce GHGs emissions and can benefit the company. Based on 106,267 m3 of POME, GHGs emissions prior the project implementatation is 44,767.80 t CO2e. The potential GHGs emissions reduction ranges from 66.64% to 74.26% during 2021-2030. Financial analysis indicates that the project is feasible, at both low and high CER market prices. The low CER results in NPV, BCR and IRR values of 18,55 billion IDR, 1,19 and 11,46%, respectively, while high CER results in NPV, BCR and IRR values of 19,65 billion IDR, 1.21 and 11,69%, respectively.
Keyword: cashflow, CDM, GHGs, PLTBg, POME

Judul: The Greenhouse Gas Reducing Strategy by Converting Palm Oil Mill Effluent into Electricity (Case Study in Lampung Province).
Abstrak: Palm oil is one of prime plants and it has strategic role in Indonesia economy in the past, present, and future. In addition to being one of national income sources, palm oil also becomes living making of many people in Indonesia. Currently, Indonesia is the biggest palm oil producing country in the world. Palm oil in Lampung province is also an important plantation commodity. There were 13 palm oil mill units operating in Lampung. Strategies of palm oil industry development were directed to plantation corporations in public scales. The reason wass the limited plantation fields compared to high public interests to make palm oil plantation investments. Processing of palm oil fresh fruit bunches into crude palm oil (CPO) results in a lot of palm oil mill effluent (POME). POME has high values of BOD and COD, suspended solid and total solid content that result in negative effects for the environment. POME in Indonesia has been processed in a relatively simple procedure so that POME produces foul odor and methane gas emission. Methane gas emission is one of greenhouse gasses contributing to global warming with 20-30 folds stronger effect than carbon dioxide gas. United States government even stated that Indonesia palm oil derivative products were environmentally unfriendly considering facts that Indonesia only had 5.5% POME processing system to capture methane gas. On the other hand, methane gas is a biogas being able to use a source of renewable energy production. The objectives of this research were (1) to obtain initial descriptions of POME processing problems; (2) to evaluate contents of POME processing technologies; (3) to determine the best temperature conditions of technology processing POME according to necessities; and (4) to formulate proper strategies in implementing POME processing for electric energy in Lampung province. This research used quantitative and qualitative approaches with primary and secondary data. Primary data were obtained from field observations, measurements in the laboratory, direct interviews with respondents, and brainstorming. Secondary data were obtained from literary study, scientific journals, technical reports from related institutions, and research institutions. Identification and characterization of POME handling problems used descriptive method. The analysis of POME handling technology contents used THIO method. The strategy formulation used SWOT and AHP methods. The alternative technology development for POME processing was conducted with biogas production process optimization research which was analyzed with descriptive and quantitative methods. The results showed that there were 13 units of palm oil mills in Lampung province with total capacity of 622 tons/hour. The utility efficiency was about 45% with a main problem of limited raw material availability. In 2011, the POME potential produced by palm oil mills in Lampung province reached 1,286,595 m3 with average COD value above 40,000 mg/L. All palm oil mills in Lampung province had POME processing units as required by the government. POME fermentation at 55oC, 45oC, and 27-28oC required respectively 42 days to reduce COD 86.86%, 57 days to reduce COD 84.31%, and 196 days to reduce COD 57.25%. Methane productivity of POME fermentation at 55oC, 45oC, and 27-28oC are respectively 0.28 m3, 0.25 m3, and 0.19 m3 for
Keyword: Methane capture, Electrical energy, POME, GHG, and Strategy

Judul: Karakteristik Barisan Eksak Pendek HomR(N, ) dan HomR( ,N)
Abstrak: Module merupakan generaIisasi dari ruang ve}ctor, dimana pada ruang vektor skalar-skalamya berasal dati suatu lapangan (field) sedangkan pada module skaJar-skalamya merupalam unsur-unsur dan suatu ring R dengan unsur satuan. Dari suatu grup komutatif yang unsur-unsumya dipadukan dengan unsur-unsur dart suatu ring R, maka akan mengbastlk.an yang namanya R-module. Himpunan seroua fungsi homomorfisma yang memetakan dati R-module M ke R-module N dinotasikan sebagai HomiM,N), dimana HomiM,N) juga merupakan suatu R-module.
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