Judul: Kajian Peluang Aplikasi Produksi Bersih di Industri Kelapa Sawit. Studi Kasus di PT Perkebunan Nusantara IV (Persero) Unit Usaha Adolina-Perbaungan, Sumatera Utara
Abstrak: Palm oil mill is one of the most important industries that supporting the Indonesian’s economy in vacancy of employment, the provision of industrial raw materials, development, and sources of national revenue from non-gas sector. Palm oil mill produces CPO (Crude Palm Oil) and PKO (Palm Kernel Oil). Environmental pollution is one of consequence from palm oil mill that needs special concern. This condition can make a dangerous effect for human and environment. Cleaner production is one of the efforts to improve effectiveness, efficiency of the process, and minimize waste. This research identifies the alternatives recommended of cleaner production in palm oil mill using the case study of palm oil mills at PT Perkebunan Nusantara IV (Persero) Unit Usaha Adolina. The focus of the analysis is done by looking at the financial aspects of the implementation of the recommended alternative. Determination of priorities to be carried out by AHP (Analytical Hierarchy Process) from experts. The analysis showed that implementation of recommended alternative provide some benefits. The application of good house-keeping will give financial gain Rp. 1.8941 billion/year, process modification will provide Rp. 0.2843 billion/year, and on-site reuse of Rp. 1.6934 billion/year. Alternative assessment of AHP seen from technical factors, economic, and environmental. The priority of alternative that will be implemented are optimization Standar Operational Procedure (0.179), efficiency of water use (0.167), good operating procedures (0.152), use of palm oil mill effluent as biogas (0.152), optimizing the utilization of EFB (0.116), FFA controlling (0.104), collecting split oil by making condensate pond (0.083), and the last is preventing contaminant of FFB (0.046).
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Judul: Kajian Penerapan Produksi Bersih pada Agroindustri Minyak Goreng Kelapa (Studi Kasus di Koperasi Wanita Srikandi)
Abstrak: Penerapan produksi bersih pada agroindustri minyak goreng kelapa dilakukan untuk meminimalkan limbah dan mencegah kehilangan sumber daya. Penelitian ini bertujuan mengkaji peluang produksi bersih pada proses produksi minyak goreng kelapa. Tahapan penelitian mencakup analisis quick scan, identifikasi aliran material, energi dan limbah, penentuan alternatif produksi bersih, analisis kelayakan teknis, lingkungan dan finansial berupa benefit cost ratio (B/C ratio) serta payback period (PP), penentuan prioritas penerapan produksi bersih dengan metode perbandingan eksponensial. Rantai proses terdiri dari pembuatan minyak klentik di tingkat pemasok, kemudian dilanjutkan menjadi minyak goreng kelapa di tingkat pabrik. Alternatif produksi bersih pada tingkat pemasok adalah: (1) pengolahan nata de coco (B/C ratio 1,17 dan PP 0,74 tahun), (2) pengolahan pupuk kompos (B/C ratio 1,26 dan PP 0,29 tahun), serta (3) pembuatan maggot (B/C ratio 1,75 dan PP 0,45 tahun). Alternatif produksi bersih pada tingkat pabrik adalah: (1) penjadwalan produksi (B/C ratio 170 dan PP 0,05 bulan), (2) perbaikan SOP penuangan minyak (B/C ratio 4,55 dan PP 0,01 tahun), (3) water recycle (B/C ratio 2,99 dan PP 4,23 tahun), dan (4) penggantian instalasi pipa (B/C ratio 3,95 dan PP 0,05 tahun). Prioritas alternatif yang direkomendasikan pertama pengolahan pupuk kompos untuk tingkat pemasok dan penjadwalan produksi untuk tingkat pabrik., The application of cleaner production in the coconut cooking oil agroindustry carried out to minimize waste and prevent resources lost. This study aims to examine the opportunities for cleaner production in the process of coconut cooking oil. Research stages included quick scan analysis, identification of material flow, energy and waste, determination of cleaner production alternatives, technical, environmental and financial feasibility analysis as benefit cost ratio (B/C ratio) and payback period (PP), and determining priorities for the application of cleaner production with the exponential comparison method. The process chain consists of the crude coconut oil production at supplier level, then continuing into the coconut cooking oil at factory level. Alternative cleaner production at the suppliers level is (1) nata de coco processing (B/C ratio 1.17 and PP 0.74 years), (2) composting (B/C ratio 1.26 and PP 0.29 years), and (3) maggot production (B/C ratio 1.75 and PP 0.45 years). Alternative cleaner production at the factory level is (1) production scheduling (B/C ratio 170 and PP 0.05 months), (2) improvement in oil pouring techniques (B/C ratio 4.55 and PP 0.01 years), (3) water recycle (B/C ratio 2.99 and PP 4.23 years), and (4) pipe installation replacement (B/C ratio 3.95 and PP 0.05 years). The first recommended alternative priority was compost processing for supplier level and production scheduling for factory level.
Keyword: Cleaner production, coconut cooking oil, crude coconut oil

Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
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