Judul: Pembuatan Briket Arang Dari Campuran Kulit Kacang, Cabang Dan Ranting Pohon Sengon Serta Sebetan Bambu
Abstrak: Introduction. One of waste utilization or organic garbage is as raw material of charcoal briquette. Charcoal Briquette can support energy need of human. Charcoal Briquette can be made by material which contain lignin and cellulose like waste or organic garbage where can be got in human life like nutshell waste, logging waste of tree of sengon which has branches and sticks, and also waste of bamboo slice. Making charcoal briquette which comes from waste or organic garbage can be alternative solution for solving garbage and can be new alternative sources of energy. Method. Making charcoal briquette is prepared raw material at first. It is continued by processing combustion with kiln drum (temperature at 500oC-1000oC). Next, it uses crashing and buffering charcoal (filter at 35 meshs) to become dust which has charcoal size of 35 meshs or more. Making starch glue (5% derived from charcoal weight) is mixing and cooking tapioca flour with water (1:12). Charcoal Dust is mixed with starch glue and it will be printed by pressure at ± 9 tons to become charcoal briquette. Then, briquette is tested physical in properties (water content, density and pressure stability) and chemical characteristic ( ash content, volatile matter content, content of bounded carbon, calorie value). Result and Discussion. Result of test in physical and chemical properties of charcoal briquette showed water content average of 1,57%-2,18%, ash content of 10,92%- 15,09%, volatile matter content of 19,28%-41,36%, content of bounded carbon of 44,32%-66,48%, density of 0,40 g/cm3-0,53 g/cm3, pressure stability of 9,99 kg/cm2- 15,89 kg/cm2, and calorie value of 5175 cal/g-6299 cal/g. Conclusion. Mixing nutshell charcoal, branch and tree stick of sengon and bamboo slice could be made for briquette and it had high enough value in calorie (5175kal/g -6299 kal/g). Four briquettes which had been produced were only briquette of Nutshell charcoal of Bamboo Sengon (KKSB) which got quality standard of Japan charcoal briquette at calorie value (6299 cal/g). But, Four briquettes didn’t get standard of charcoal briquette of America, Indonesia and UK. Composition of mixture-charcoal influenced charcoal density and calorie value. Composition of mixture-charcoal didn’t effect charcoal water content, ash content, volatile matter content, content of bounded carbon and pressure stability value.
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Judul: Analisis Briket Arang Berbahan Dasar Limbah Organik Padat Sebagai Bahan Bakar Alternatif
Abstrak: Penelitian ini bertujuan untuk mengetahui mutu briket arang berbahan dasar tempurung kelapa, serbuk gergaji kayu jati dan sekam padi berdasarkan standar SNI dengan parameter kadar air, kadar abu, kadar zat menguap dan kadar karbon serta variasi komposisi bahan baku terbaik terhadap mutu briket arang yang dihasilkan. Briket arang dibuat dengan cara konvensional dengan komposisi arang tempurung kelapa, serbuk gergaji kayu jati dan sekam padi yang berbeda serta penambahan perekat kanji. Hasil penelitian menunjukkan mutu briket arang sebagai berikut, kadar air 28,09 - 33,07 %, kadar abu 24,06 - 31,16 %, kadar zat menguap 2 – 18 % dan kadar karbon 53,45 – 70,41 %., This study aims to determine the quality of charcoal briquettes made from coconut shell, teak sawdust and rice husks based on SNI standards with parameters of water content, ash content, volatile matter content and carbon content as well as variations in the composition of the best raw materials on the quality of the produced charcoal briquettes. Charcoal briquettes are made in a conventional way with different compositions of coconut shell charcoal, teak sawdust and rice husks and the addition of starch adhesive. The results showed the quality of charcoal briquettes as follows, water content 28,09 – 33,07 %, ash content 24,06 – 31,16 %, volatile matter content 2 – 18 % and carbon content 53,45 - 70,41 %.
Keyword: coconut shell, teak sawdust, rice husk, charcoal briquettes

Judul: Pendugaan Peri ode dari Proses Poisson Periodik
Abstrak: In this manuscript a method for estimating period T of a periodic Poisson process which is observed in interval [O,nj is discussed. From the research that has been done, it has been proven that the estimator for T is consistent if the length of interval observation of the process goes to infinity. Subsequently, rate of consistency of the estimator is also shown. Finally, a simulation has been carried out to compare behavior of the estimator with the one which considered has a better estimator. The resuit of the slmuiatlon shown that there is no slgnlficant different between two estimators.
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