Judul: iKajian Produksi Bersih pada Kawasan Industri Penyamakan iiKulit di Garut
Abstrak: Leathers is one of livestock products that being expensive commodity today. Positively, leather tanning industry gives benefit to the peoples around industry, however, improper handling of wastes may pollutes the environment around tanning industrial estate. Cleaner production strategy is needed to minimize the wastes. This research was directed to identify the opportunity implementation of cleaner production strategy on leathers tanning industry at Sukagerang, Garut and to determine the possible alternatives of cleaner production options to increase production efficiency while minimizing the wastes. Analysis of Cleaner production conducted in three industries, PT ELCO Indonesia, PT Karya Lestari Mandiri, and PD Putra Setra. Quick Scan method used to analyzed the cleaner production. The results were then analyzed by using Exponential Method Comparison (MPE) and method of Analytical Hierarchy Process (AHP) to determine the priority of cleaner production application. Priority selection of cleaner production alternatives in leather tanning industry estate was analyzed based on the environmental criteria, benefits, construction, operation, and cost. The best alternative priority to be applied in leather tanning was controlling of water use then followed by trimming process before chemical treatment, breeders assisting, retribution for waste treatment, and the socialization of research results. In the case study of water use at PD Putra Setra, 87,800 Liters water can be reduce. While in the case study of trimming process at PT ELCO Indonesia, this alternative may result in the benefit to the company in the form of savings for the purchase of chemicals of 16.82% or equivalent to Rp 197,103.
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Judul: Kajian Implementasi Produksi Bersih di Industri Penyamakan Kulit (Kasus Desa Cibuluh, Kecamatan Bogor Utara)
Abstrak: Leather tanning industries are industries that process animal skin to produce finish leather product by using many stages of process. Every stage of the process will generate a large amount of wastes, either liquid or solid wastes. If the waste is not treated properly, it will cause environmental pollution. Implementation of cleaner production strategy can be used to solve this problem. This research studies the potentials of cleaner production application and alternative of cleaner production strategy in order to develop environmental friendly tanning industry in Cibuluh. The method used was process identification, waste sourch identification, and cleaner production analysis strategy. The cleaner production alternatives which are potential to be applied are design of installation wastewater to IPAL with pipe from molen machine, reuse wastewater from pre soaking process for the next batch, separation wastewater from hair and flesh, processing of fleshing waste for fat, and recycle chromium from tanning wastewater. Based on the priority alternative, three options were selected, namely recycle chromium from tanning wastewater, separation wastewater from hair and flesh, and reuse wastewater from pre soaking process for the next batch. The total investment of these option is Rp 2,059,500,- with pay back period (PBP) of 0.17 month. The Analitycal Hierarchy Process (AHP) analysis result shows that industrial policy is the most important factor to minimize waste product of tanning industry. The priority of cleaner production program from AHP analysis is recycle chromium from tanning wastewater which is consistent to that resulted from field study.
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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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