Hasil Pencarian  ::  Simpan CSV :: Kembali

Abstrak :
ABSTRAK
Penelitian torrefaksi bonggol jagung telah dilakukan untuk mempelajari pengaruh laju alir nitrogen terhadap yield dan komposisi bonggol jagung yang dihasilkan melalui proses torrefaksi. Pengaruh laju alir nitrogen diteliti dengan memvariasikan laju alir nitrogen sebesar 0,3 L/min, 0,5 L/min, dan 0,7 L/min dengan masing-masing variasi laju alir nitrogen dilakukan pada 3 variasi suhu torrefaksi, yaitu 250oC, 275oC, dan 300oC. Proses torrefaksi berlangsung di reaktor tubular dengan holding time 20 menit, heating rate 10oC/menit, dan total massa umpan 15 gram. Identifikasi pengaruh laju alir nitrogen dilakukan dengan menganalisis bonggol jagung hasil torrefaksi dengan menggunakan karakterisasi FTIR, Ultimate, dan Thermogravimetri Analysis (TGA). Hasil penelitian ini menunjukkan bahwa terdapat pengaruh laju alir nitrogen terhadap yield dan komposisi bonggol jagung hasil torrefaksi. Semakin besar laju alir nitrogen maka yield dari bonggol jagung hasil torrefaksi akan semakin kecil. Semakin besar laju alir nitrogen, kandungan oksigen dalam bonggol jagung hasil torrefaksi akan semakin berkurang dan kandungan karbonnya meningkat. Kandungan oksigen setelah torrefaksi menurun hingga 38% pada saat suhu torrefaksi 300oC dengan laju alir nitrogen sebesar 0,7 L/min sementara kandungan karbonnya meningkat hingga 44% bila dibandingkan dengan bonggol jagung umpan torrefaksi, rasio C/O meningkat dari 0,95 menjadi 2,19 dan rasio C/H meningkat dari 6,9 menjadi 13,99. Berdasarkan karakterisasi FTIR seiring semakin besar laju alir nitrogen maka gugus fungsi fenol, guaiacol, catechol, dan ether akan semakin tinggi. Data karakterisasi TGA menunjukan bahwa laju alir nitrogen tidak berpengaruh terhadap suhu pirolisis dari bonggol jagung yang sudah ditorrefaksi. Suhu torrefaksi adalah faktor yang mempengaruhi dari suhu pirolisis bonggol jagung yang sudah ditorrefaksi.

---

ABSTRACT
Torrefaction of corn cobs has been carried out to study the effect of nitrogen flow rate on yield and torrefied corn cobs composition produced through torrefaction. The effect of nitrogen flow rate was investigated by varying the nitrogen flow rate by 0,3 L/min, 0,5 L/min, and 0,7 L/min with each nitrogen flow rate variation performed on 3 torrefaction temperature variations are 250oC, 275oC, and 300oC. Torrefaction process takes place in a tubular reactor with a holding time of 20 minutes, a heating rate of 10oC/ minute, and a total feed mass of 15 grams. Identification of the effect of nitrogen flow rate was carried out by analyzing the torrefaction corn cobs using FTIR, Ultimate, and Thermogravimetric Analysis (TGA) characterizations. The results of this study indicate that nitrogen flow rate affects yield and torrefied corncobs composition. The greater the nitrogen flow rate, the lower is the yield of torrefied corn cobs. The greater the flow rate of nitrogen, the lower is the oxygen content in the corn cobs and the higher is the carbon content. The oxygen content after torrefaction decreased up to 38% when the torrefaction temperature was carried out at 300oC with a nitrogen flow rate of 0.7 L/min while the carbon content increased by 44%, the C/O ratio increased from 0,95 to 2,19 and the C/H ratio increased from 6,9 to 13,99. Based on FTIR characterization, increasing nitrogen flow rate increases the functional groups furan, phenol, guaiacol, catechol, and ether. Based on the TGA characterization, the nitrogen flow rate did not affect the pyrolysis temperature of the torrefied corn cobs. Torrefaction temperature is a factor that influences the pyrolysis temperature of torrefied corn cobs.

Abstrak :
ABSTRAK
To overcome the problem of fuel dependence from imports and reduce the burden of fuel subsidies in the APBN, starting in 2007 the Government has implemented a conversion program for fuel use in the household sector from kerosene to LPG. The program has been running successfully. However, the same problem as before reappeared. The higher LPG needs depend on imports, reaching 70 percent of total consumption. Likewise, the burden of LPG subsidies in the state budget is even higher. Indonesia has the potential to produce abundant biomass energy and has been used as household fuel, especially in rural areas. However, the utilization is still by burning firewood using traditional inefficient combustion stoves that produce air pollutant that causing a negative impact on family health. Changes in the way biomass energy are used through the transformation of biomass into pellets and the use of technology biomass stoves can overcome the problems. This paper aims to analyze and provide policy recommendations to develop biomass energy utilization in households in a healthy manner and can improve combustion efficiency. The widespread use of biomass energy by households will reduce the dependence on LPG imports and reduce the burden of subsidies in the state budget.

Abstrak :
ABSTRAK
Material biomassa seperti lignin, pati, dan selulosa merupakan limbah dalam proses pengolahan bubur kayu dan kertas. Pemanfaatan ulang limbah biomassa sebagai material baru belum banyak dilakukan dan umumnya hanya sebagai bahan bakar saja. Dalam penelitian ini dilakukan sintesis busa poliuretan-bio hibrida berbasis material biomassa dengan melakukan poliuretanisasi. Proses sintesis busa poliuretan-bio berbasis material biomassa menggunakan diisosianat berupa Toluene Diisocyanate 80 TDI80 dan poliol berupa Polipropilen Glikol PPG 2000. Variabel bebas yang digunakan antara lain variasi jenis material biomassa lignin, pati, selulosa sebanyak 21 gram. Hasil yang diperoleh menunjukkan penambahan material biomassa dapat meningkatkan nilai resilience dengan nilai tertinggi oleh sampel PU-Selulosa pada 0.0039 0.0084 Mpa. Penambahan material biomassa juga meningkatkan nilai stabilitas termal busa poliuretan bio dengan nilai tertinggi pada 418.754oC oleh sampel PU-Pati. Morfologi busa poliuretan-bio hibrida berbasis material biomassa cenderung tertutup dengan beberapa partikel yang menempel pada dinding sel busa.

---

ABSTRACT
Biomass material such as lignin, starch, and cellulose are a pulp and paper fabrication rsquo s waste. The utilization of lignin as a new materials is not exessive, usually used only as a fuel. Therefore, in this study hybrid biomass based polyurethane bio foam was fabricated by reacting the biomass materials with polyurethane. The syntesis of the hybrid biomass based polyurethane bio foam used Toluene Diisocyanate 80 TDI80 and Polypropylene Glycol PPG 2000 as the polyol. Various kind of biomass material of 21 grams were used as variables of the sample. Samples of hybrid biomass based polyurethane bio foam was characterized by FTIR, STA, SEM, and some of mechanical properties testing. The result showed that biomass material can increase the resilience of hybrid bio polyurethane foam which stood at 0.0039 0.0084 Mpa for PU Cellulose sample. The addition of biomass material also increase the thermal stability which stood at 418.754oC for PU Starch sample The cell morphology of hybrid biomass based polyurethane bio foam were closed with some particle stick onto the cell wall.

Abstrak :
Kebutuhan akan pemanfaatan EBT semakin meningkat dalam rangka mengurangi emisi fosil yang menyebabkan kenaikan suhu lingkungan secara signifikan. Salah satu potensi EBT yang dapat dikembangkan di Indonesia adalah EBT berbasis biomassa. Pemanfaatan biomassa hanya menyumbang 10% dari bauran EBT di Indonesia. Laboratorium Gasifikasi Universitas Indonesia memiliki alat Biomass Gasifier dengan kapasitas 10 kW listrik. Teknologi gasifikasi menggunakan jenis downdraft yang cocok digunakan untuk skala kecil. Alat tersebut dapat digunakan untuk langsung mengkonversi sekam mentah menjadi energi listrik maupun panas, namun belum diketahui kemampuan alat ini untuk bahan bakar lainnya. Sehingga penelitian ini berfokus untuk mengetahui mengetahui bahan bakar yang paling ekonomis sebagai bahan bakar. Parameter keekonomian yang digunakan pada penelitian ini yaitu menggunakan parameter LCOE, NPV, IRR, PBP, dan BCR. Hasil perhitungan menunjukkan bahwa biomassa ampas tebu memiliki keekonomian paling tinggi, dengan potensi energi listrik sebesar 18,50 kW memiliki nilai LCOE sebesar Rp 1.265,99/kWh dengan NPV positif, IRR 12,8%, PBP selama 5,48 tahun dan BCR 1,11. Berdasarkan analisa sensitivitas, parameter harga bahan bakar biomassa merupakan paling berpengaruh terhadap perubahan nilai LCOE sehingga pemilihan harga biomassa menjadi faktor utama yang mempengaruhi nilai keekonomian biomass gasifier. ...... The demand for the utilization of renewable energy sources is increasing to reduce fossil fuel emissions, which contribute significantly to environmental temperature rise. Biomass-based renewable energy technology holds great potential for development in Indonesia. However, biomass utilization currently accounts for only 10% of the overall renewable energy mix in the country. The Gasification Laboratory at the University of Indonesia has developed the Biomass Gasifier, a downdraft gasification technology suitable for small-scale applications, with an electrical capacity of 10 kW. This tool can directly convert raw rice husks into electrical energy and heat, but its performance with other fuel sources remains unknown. Therefore, this research aims to identify the most economically viable fuel source for the Biomass Gasifier. Economic parameters, such as Levelized Cost of Electricity (LCOE), Net Present Value (NPV), Internal Rate of Return (IRR), Payback Period (PBP), and Benefit-Cost Ratio (BCR), are employed to analyze the economic feasibility of different fuel options. The calculation results show that bagasse biomass has the highest economic potential, with a potential of 18.50 kW of electrical energy having an LCOE value of IDR 1,265.99/kWh with a positive NPV, IRR of 12.8%, PBP for 5.48 years and BCR 1,11. Based on the sensitivity analysis, the parameter of the price of biomass fuel has the most influence on changes in the value of LCOE so that the selection of the price of biomass is the main factor affecting the economic value of the biomass gasifier.

Abstrak :
Menjadi pengusaha yang sukses, seharusnya juga mampu mengembangkan usaha yang dijalankannya dengan baik. Salah satunya adalah dari sisi pembiayaan perusahaan. Masalah pembiayaan perusahaan tidak hanya di alami oleh perusahaan besar, namun juga perusahaan kecil skala UKM. Alternatif pendanaan yang ada bersifat bebas dan siap untuk digunakan. Dalam hal ini pengaruh dari diri seorang pengusaha juga ikut andil untuk membuat perumusan keputusan alternatif pendanaan mana, yang akan digunakan. Modal manusia umum dan Modal sosial manusia menjadi faktor yang mempengaruhi. Oleh sebab itu pengetahuan seorang pengusaha perlu ditingkatkan untuk dapat mengetahui dan memutuskan alternatif pendanaan mana yang paling sesuai dengan usaha yang sedang dijalankannya.

---

Being a successful entrepreneur, it should also be able to develop a business being operated properly. One is from the finance company. The issue of financing the company not only experienced by large corporations, but also small-scale enterprises SMEs. Alternative funding is freely available and ready for use. In this case the influence of an entrepreneur themselves also contribute to make the decision formulation which financing alternatives, which will be used. General human capital and social capital factors that affect the human being. Therefore, knowledge of an entrepreneur needs to be improved to be able to know and decide which financing alternative that best suits your business is being run.

Abstrak :
Many of the world's leading experts have contributed to this volume on biofuel pretreatment, making it a valuable and authoritative sourcebook that covers the variety of biomass types, such as molasses and cheese whey, and a range of treatment techniques

Abstrak :
Arsenic is a ubiquitious element in the environment and occurs naturally in both organic and inorganic forms. Under aerobic condition, the dominant form of arsenic in waters in arsenata, which is highly mobile and toxic....