Judul: Audit energi pada produksi teh hitam ortodoks di PTPN IX (Persero) Kebun Jolotigo, Pekalongan
Abstrak: Energy audit is the activity to identify potential energy savings with energy conservation in a system, facilities and equipment that already exist. The process of tea production in Jolotigo includes seedling, planting, cultivating, picking and carrying, withering, rolling, fermenting, drying and dry sorting. The aim of this study is to conduct energy audit on the black tea production process in PT. Perkebunan Nusantara IX (Persero) Jolotigo, Pekalongan. The results of the study are to gift the information about the energy flow at every state of the production process and the energy type that required producing per unit of product as well as withering and drying system efficiency. Energy resources used in the process of tea production are energy of fertilizers, pesticides, human, electricity, fuel oil and biomass from solid fuel wood of tea. Energy consumption to produce one kilogram of dry tea is 57.32304 MJ. The energy consumption in the production of black tea are 6.5% of human labor, 1.4% of electricity, 6.06% of fuel oil, 72% of solid fuel, 12.5% of fertilizer energy , and 1.5 % derived from pesticides. The largest energy of production stage that require is the withering which is 26.73682 MJ / kg dry tea (46% of total energy consumption), while the smallest stage energy is the packaging which is 0.013922 MJ / kg dry tea (24% of total energy consumption). Wood solid fuels that dominate energy consumption of the process used for solid fuel are withered and dried. Withering has 5.41% system efficiency, and drying has 24%. Energy saving can be done in wood fuels consumption, intensive investigation on the heat exchanger, flue, as well as factory equipment.
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Judul: Audit energi pada proses produksi teh hitam di Perkebunan Gedeh PT Perkebunan Nusantara VIII Kabupaten Cianjur, Jawa Barat
Abstrak: Teh (Camelia Sinensis. L) adalah salah satu hasil pertanian dari sub sektor perkebunan yang menghasilkan devisa bagi negara sebesar 94.6 juta US$ atau 0.22% dari total devisa yang berasal dari non migas. Dalam proses produksi teh, aspek efisiensi penggunaan energi tidak dapat dipisahkan dari setiap kegiatan produksi, sebab agroindustri khususnya industri pengolahan teh merupakan suatu bisnis yang harus menguntungkan sehingga dapat berkelanjutan. Audit energi merupakan langkah awal dalam pelaksanaan efisiensi dan konservasi energi. Audit energi dapat membantu memberikan gambaran penggunaan energi pada suatu proses produksi dan identifikasi terjadinya pemborosan energi. Tujuan penelitian yang dilakukan adalah melakukan audit energi pada proses produksi teh hitam di Perkebunan Gedeh, PT. Perkebunan Nusantara VIII (Persero), Cianjur, Jawa Barat. Sasaran penelitian untuk mengetahui jumlah dan jenis energi yang dibutuhkan untuk menghasilkan per satuan produk teh hitam serta mengetahui aliran energi dalam proses produksi tersebut. Hasil penelitian menunjukan bahwa konsumsi energi total pada proses produksi teh hitam di Perkebunan Gedeh PT. Perkebunan Nusantara VIII adalah 50.39489 MJ/kg teh kering. Yaitu 26.41055 MJ/kg teh kering (52.41%) dibutuhkan pada tahap produksi pucuk teh, 1.00062 MJ/kg teh kering (1.98%) untuk transportasi dari kebun ke pabrik pengolahan, dan 20.96809 MJ/kg teh kering (41.61%) dibutuhkan pada tahap pengolahan pucuk teh menjadi teh kering siap ekspor.
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Judul: Grup dan Homomorfisma Grup pada Rubik Revenge
Abstrak: Rubik cube is a kind of puzzle game. A player must arrange rubik sides, which have been disordered, back to the position where every side has the same colour. This paper does not focus on the settlement solution, but instead on proving the existence of a group homomorphism between rubik movement group and S96 symmetric permutation group in rubik revenge. Firstly, it has been proved that rubik movement set is a group. Then, it also has been proved that the M set, which contains numeric labels of 1 until 96 in cubinos sides, is S96 symmetric permutation group.
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