Judul: Analisis kinerja dan efisiensi energi prototipe alat penyulingan untuk industri kecil minyak nilam
Abstrak: Patchouli oil is high value essential oil of Indonesia that is produced by the steam distillation process from patchouli plants (Pogostemon cablin benth). As an export commodity, patchouli oil is quite substantial to fulfill the world demand in perfumery, cosmetic and pharmacy industries. Patchouli oil has always been possessed an increasing world market in spite of facing hard competition and nontariff barrier in the world trade. Therefore it needs to increase continuously the productivity and efficiency of essential-oil agroindustries. Distillation process for patchouli oil in small scale in general still represent simple technology process with equipments which are made from corrosive material. The most common method of essential oil production is water and steam distillation and conducted only based on experience so that the efficiency is usually low. Therefore this research evaluate aimed to the efficiency both kohobasi system and non kohobasi system. The objective of this research were to study and examine the performance of distillation equipment, analyze energy efficiency of distillation system prototype and analyze the quality of patchouli oil. The distillation method of 37,5 kg of patchouli plants was water and steam distillation with kohobasi system and non kohobasi system for 8 hours period. The distillation equipment to produced patchouli oil were retort with furnace, condenser and separator. This research used biomass energy such as fire woods as fuel. Furnace performance analysis based on several parameters which were surface area of heat transfer, woods burning process and the usage of fuels. The wide surface of heat transfer on retort is 1,70 m2. Distillation process with kohobasi system used dry fire woods of 143,32 kg and non kohobasi system used 138,2 kg of dry firewoods. The energy from firewoods used for boiling dan vaporize water in retort. According to the result, in kohobasi system the energy is needed to boiling and vaporize the water into steam is 644,51 MJ and the energy from firewoods is 2.579,85 MJ. The retort efficiency at that condition is 25 %. In non kohobasi system the energy is needed to boiling and vaporize the water into steam is 572,24 MJ and the energy from the fuel is 2487,6 MJ. The retort efficiency at that condition is 22,99 %. Retort performance bases on several parameters like bulk density, distillation rate and steam penetration. Bulk density for kohobasi system was 0,09 kg/l and 0,096 for non kohobasi system. Distillation rate for kohobasi system was 0,74 l/hour and 0,63 for non kohobasi system. Condenser efficiency for kohobasi system is 79 % and 99,26 % for non kohobasi sytem. The difference efficiency between kohobasi sytem and non kohobasi system is influenced by cold water flows. Cold water flows continuously in non kohobasi system result in higher efficiency than in kohobasi system. Average distillate temperature for kohobasi system was 31,56 °C and 30,35 °C for non kohobasi system. The yield of patchouli oil for kohobasi system was 2,29 % (dry basis) and 2,2 % (dry basis) for non kohobai system. The quality of patchouli oil produced by kohobasi system and non kohobasi system is quite comparable, the oil has specific
Keyword: 

Judul: Analisis Kinerja Prototipe Separator Penyulingan Minyak Nilam
Abstrak: Patchouli oil is an Indonesian important essential oil with the biggest total production compared to similar commodities. Indonesia is a major producer of patchouli oil in the world with almost 90% market share. The total production of Indonesian patchouli oil in 2006 reached 2.832.413 kg or the equivalent of U.S. $ 43,984,079. Until now, most of patchouli oil is still produced in small-scale distillation with a simple technology, corrosive materials, and low efficiency. Separator is a part of distillation equipment that has not undergone many improvements. Therefore, research needs to be done on a separator considering the patchouli oil including an oil that tend to be more difficult to separate from water so there was big loss potential on separator. The objectives of this study are to evaluate the performance of separator of IKM (Small Medium Industry) and then compare it with the performance of the prototype separator that has been developed. Observed factors are the distillate temperature and the flow rate with oil loss as a response. The range of distillate temperatures and distillate flow rate in this IKM, respectively 38,5-60 oC and 1,28-2,72 liters/minute. The range of oil loss that occurs is 2,11 % - 4,35 % with an average value 3.13%. The result of Patchouli Alcohol (PA) Levels Test for waste oil (loss) with alcoholmeter indicates a PA level is bigger than 34%. Waste oil density is 0.992 g/ml. At higher distillate temperatures there is a decreasing trend of oil loss while at the bigger distillate flow rate there was a greater tendency to increase oil loss. Prototype separator was designed based on the distillate flow rate and distillate temperature at the separator of IKM performance test. This separator has an inner cylinder to help the oil separation process. The top of the separator is made of glass to make it easier to monitor the amount of oil. The tip of the glass made narrowed to minimize surface contact between water and oil so facilitate the collecting process of oil. The oil removed from the separator through a pipe with faucet at the end. Separator prototype made of stainless steel. Prototype separator has a very good performance. In the separator prototype performance test, the range of oil loss is 0.09 % - 0.24 % with an average value 0.16%. The waste water from separator prototype more clearly than the waste water from separator of IKM. Separator prototype no longer need additional tool such as foam and big spoon in collecting oil.
Keyword: 

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.
Keyword: