Judul: Peningkatan Kinerja Proses Penyulingan Minyak Pala Dengan Metode Uap Langsung
Abstrak: Nutmeg oil is one of Indonesian important export commodity. For the last six years (1996-2001), it's price in the word market has showed an inclined increasing. In 1999, the nutmeg oil price reached the average price of 26.18 US dollar/kg. In the beginning of 2000, the average price of Indonesian nutmeg oil in the world market returned to increase and achieved the average price of33.38 US dollar/kg. The market opportunity which is still prospective as well as the raw material availability become the fundamental aspect of the developing the nutmeg oil industry in Indonesia. For the time being, essential oil production existing in Indonesia is small scale industry. The common problem which found, was the long distillation duration which takes 48-52 hours for nutmeg kernel distillation and 72 hours for mace distillation. It caused the high consumption of energy/fuel. The condition was very contradictive to the energy prices which is always increase. In the other side, a sceintific point of view considering the optimum material size as well as the uniform vessel pressure distillation in each small sclae distillation factory is not yet being under attention. The objective of this work is to improve the performance of nutmeg oil distillation process by reducing the duration of distillation process. The specific objective is to find out the effect of material size and vessel pressure to the yield and quality of resulted nutmeg oil from the young nutmeg kernel and mace using direct steam distillation method. The size of nutmeg kernel observed in the experiment was categoried in fine, which was the output of 0.3 cm strainer hole diameter mill; semi rough, which was the output of 0.5 cm strainer hole diameter mill; and rough, which was the output of 1.0 cm strainer hole diameter mill. The distillation conducted of a vessel pressure of 0 atm gauge, with a duration of 12 hours. All experiment run was conducted twice. In second experiment stage, the vessel pressure was levelled to 0.5 and 1.0 atm gauge in order to provide a better process condition. This stage was conducted based on the nutmeg kernel size which given the highest yield as the consideration to determine the best atmospheric pressure in the vessel in perspective of resulting the highest nutmeg oil yield and meet the quality standard. All experiment run was conducted twice and with duration 12 hours The average water content of raw material used was 16.84 % (% v/w), while the average oil content of the raw material used was 17.58 % (%v/w, wet basis). The kernel size of 0.5 cm resulted the highest yield of oil compared to the two other kernel size, it has 12.98 % (% v/w, wet basis) or 11.65 % (% w/w, wet basis). As well as distillation rate in a period of two hours. At the end distillation process, the kernel size of 0.5 cm has succeeded to distill the nutmeg oil from the material in amount of 73.83 %. Thus, the kernel size of 0.5 cm was the best yielded material size compared to the two other material size
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Judul: Efisiensi Energi Dan Kinerja Prototipe Alat Penyulingan Minyak Pala Berbahan Bakar Kayu
Abstrak: Indonesia is a richest country that has big enough nutmeg oil production in the world. Indonesian nutmeg oil contain high quality essential oil and its export quantities has dominated world market of Nutmeg oil. The increasing of fossil fuel price and its alternative have implicated to their availability, especially kerosene that usually used by Nutmeg oil distillators, as the primary fuel. Transformation of energy to energies with enough cheap price and available is need to minimize production cost. Two examples of them is wood and coals. In this recent time, the cheapest price is wood. The average of wood price is about Rp 500 / kg with the average of water contain is about 30%. Prototype of Nutmeg oil distillation equipments that examined is made to give a solution to distillation processor. Series of this prototype is divided to boiler, distillating cattle accomplying with material cattle and material fraction, spiral condensor with water container and oil separator. This prototype is examined by factors that suitable with recommended standardation and the former research that result as the best factors. From the refferences, the process is done by 12 hours to be efficient process, compare with the conventional time scale of process is about 30–48 hours. From this examining, the output that will be resulted are efficiency of heat energy, performance and the lacking of performance of the prototype. Input factor that used on this prototype is loading material into the cattle as much 300 kg of Nutmeg that have been crushed to the small pieces. The other factor is maintaining pressure in the cattle 1 atm gauge, and flow of condensate as 0.6 liter/hour.kg of material or same with 50 ml of distillate/second, and fluidizing of cooling water after the first hour distillation. Analysis of the average efficiency of energy of boiler results efficiency as 31,59%, the cattle as 91,79%, condenser as 90,87% for recovery efficiency and 99% for transfer efficiency. Beside that, efficiency of conducting pipes between boiler and cattle as 97,27%, and conducting pipes between to condenser cattle as 99,49%, and so the total of efficiency of energy on the distillatory is 25,54%. The distillate or oil from this distillation process has characteristic oil that suitable with SNI 06-2388-2006 about Nutmeg oil characteristics. Responses of combination values of density is about 0,904, refractive index is 1,478, its solution in ethanol 90% at temperature 20°C is 1:1, optical rotary is (+)16,8º, and vapor remain is 0,7%. Standardize from SNI of the density is about between 0,880-0,910, refractive index between 1,470-1,497, solution in ethanol 90% at temperature 20°C is 1:3 and then clarity, optical rotary between (+)8º-(+)25º, and vapor remain is 0,7%. After the examination and analysis of Nutmeg oil, the time of distillation process is determined by 14 hours. The comparation of distillation process with distillation held by common people, on one cycles of distillation process with material about 300 kg can get economical benefit from cost of fuel consumption and operators. Fuel consumption can be reduced to 1.5 million rupiah from changing 1 liter kerosene with price Rp 7.100,- to wooden
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Judul: Cycle Hamilton pada Graf Lengkap, Graf Regular, dan Graf 2-Connected 4-Regular Berorder Kurang dari Sepuluh
Abstrak: Suatu graf disebut graf Hamilton apabila graf tersebut memuat cycle Hamilton, yaitu cycle yang melewati setiap vertex tepat satu kali. Menentukan keberadaan cycle Hamilton pada suatu graf dapat menggunakan syarat cukup yang berupa teorema-teorema yang telah diperkenalkan sejak tahun 1950-an. Beberapa syarat cukup yang dibahas dalam karya ilmiah ini adalah syarat cukup yang berhubungan dengan graf lengkap dan graf regular. Suatu graf lengkap berorder 𝑛������ ≥ 3 dan graf r-regular berorder 𝑛������ ≤ 2𝑟������ + 1 merupakan graf Hamilton, Karena kedua graf tersebut memuat cycle Hamilton. Selanjutnya, syarat cukup tersebut digunakan untuk menentukan keberadaan cycle Hamilton pada graf 2-connected 4- regular berorder kurang dari 10.
Keyword: graf Hamilton, graf regular, graf lengkap, graf 2-connected 4-regular