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"The study has been conducted to evaluate the effectiveness of the natural solvent from noni fruit for CO2 gas absorption from CH4 through hollow fiber membrane gas-liquid contactors. The solvent was made of 100 grams noni fruit per liter of water. In experiments, the solvent flowed to the shell side of the contactor, while the gas mixture flowed to the lumen fiber. The experimental results showed that mass transfer coefficients in the contactors increased with increasing liquid flow rate and decreasing number of fibers in the contactors. Mass transfer correlation indicated that the mass transfer in the contactor was dominated by turbulent flow. Hydrodynamics analysis of the contactors showed that at the same Reynolds number pressure drops increased with increasing packing density due to an increase in friction between fibers and water. The friction factor ratio data revealed that the fiber surface did not behave like a smooth pipe within the range of velocities in the experiments. Based on QI and Cussler coefficients, chemical absorption occurred during experiments, which might be indicated by the appearance of new compounds in the chemical analysis of the aqueous extract from noni fruit after absorption."

"The study has been conducted to evaluate the effectiveness of the natural solvent from noni fruit for CO2 gas absorption from CH4 through hollow fiber membrane gas-liquid contactors. The solvent was made of 100 grams noni fruit per liter of water. In experiments, the solvent flowed to the shell side of the contactor, while the gas mixture flowed to the lumen fiber. The experimental results showed that mass transfer coefficients in the contactors increased with increasing liquid flow rate and decreasing number of fibers in the contactors. Mass transfer correlation indicated that the mass transfer in the contactor was dominated by turbulent flow. Hydrodynamics analysis of the contactors showed that at the same Reynolds number pressure drops increased with increasing packing density due to an increase in friction between fibers and water. The friction factor ratio data revealed that the fiber surface did not behave like a smooth pipe within the range of velocities in the experiments. Based on QI and Cussler coefficients, chemical absorption occurred during experiments, which might be indicated by the appearance of new compounds in the chemical analysis of the a queous extract from noni fruit after absorption."

"Pada Tesis ini dibahas studi kelayakan pabrik LNG berbahan baku gas metana batubara (GMB) melalui proses pemurnian dan pencairan. Input data yang dikaji adalah komposisi GMB sehingga diperoleh teknologi pemurnian & pencairan yang cocok digunakan, keekonomian pendirian pabrik dan analisa sensitivitas serta grafik berupa patokan harga jual LNG berdasarkan IRR yang ditargetkan. Pada harga bahan baku GMB senilai $3/MMBTU, harga jual produk LNG $8/MMBTU didapat harga IRR untuk perkiraan pembangunan pabrik LNG berbahan baku GMB pada tahun 2015 didapat sebesar 24,34 % dengan NPV sebesar $ 438.031.452,06 dan payback period selama 5,49 tahun dari mulai masa konstruksi atau 3,49 tahun setelah pabrik beroperasi.

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This thesis discus about feasibility study LNG plant with coalbed methane as a feed through purification process and liquefaction. The input data uses coalbed methane compositions so that purification process technology and liquefaction technology can be selected. The economic analysis using sensitivity analysis and also graph in showing competent price directive if the suitable price of LNG based on targeted IRR. At the price of coalbed methane raw material $3/MMBTU the price for LNG product is about $8/MMBTU, the estimate IRR value for the development of LNG plant from coalbed methane gas in the year 2015 is equal to 24,34 %, NPV is equal to $ 438.031.452,06 and payback period during 5,49 year from starting the construction period or 4,73 year after plants operates."

"Mesin pada kendaraan umumnya menggunakan bahan bakar cair. Bahan bakar cair yang akan dimasukkan ke dalam ruang bakar disemprotkan menjadi bulir-bulir tetesan. Laju penguapan dari tetesan merupakan elemen utama untuk mengetahui karakteristik nya. Para peneliti menggunakan model analogi Ranz-Marshall dan pendekatan model stagnan film untuk meneliti laju perpindahan kalor dan massa pada tetesan hingga sekarang. Penelitian ini akan menggunakan kedua model tersebut untuk melihat kesesuaian model terhadap tetesan Butanol. Penelitian juga dilakukan untuk membandingkan model analogi Ranz-Marshall-Stagnant Film dan model modifikasi stagnan film yang telah diusulkan oleh E.A. Kosasih dan Alhamid M.I. Penelitian dilakukan dengan melihat laju penguapan tetesan yang dibentuk pada termokopel tipe K berukuran 0.1 mm dengan memvariasikan suhu udara dan kecepatan udara yang mengalir di sekitar tetesan. Data yang telah diolah menghasilkan bilangan tak berdimensi Reynold (Re), Prandtl (Pr), Schmidt (Sc), Nusselt (Nu), dan Sherwood (Sh). Hubungan antara bilangan tak berdimensi tersebut menunjukkan bahwa model stagnan film memiliki korelasi data yang lebih baik dibandingkan dengan model modifikasi stagnan film.

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Most of the vehicle engines use liquid fuel. The injected fuel transform into droplets as it going through the combustion chamber. Rate of evaporation of droplets is the main element to know its characteristic. Until now researcher use the Ranz-Marshall analogy and stagnant film approach to calculate the rate of heat and mass transfer. This study is going to use both of the approach to look at the suitablity model to Butanol. The study also comparing Ranz-Marshall analogy-Stagnant Film model to modificated stagnant film approach which was has been proposed by E.A. Kosasih and Alhamid M.I. This study look into the rate of droplet evaporation which is formed at the tip of 0.1 mm type K thermocouple. The air flowing around droplet is varied by its temperature and velocity. From the data, it can obtain Reynolds number (Re), Prandtl (Pr), Schmidt (Sc), Nusselt (Nu), and Sherwood (Sh). The correlation between these dimensionless number show that stagnant film approach have better data correlation than modificated stagnant film."

"Summary:A unified theory of multiphase flows, providing tools for practical applications"

"Evaluasi efektifitas pelarut dari daun mengkudu untuk absorpsi gas amonia mengunakan kontaktor membran serat berongga telah diteliti. Pelarut yang digunakan adalah daun mengkudu dengan dosis 200 gram per liter air dan asam sulfat 0.1M. Untuk studi perpindahan massa, hasil penelitian menunjukkan nilai koefisien perpindahan massa pada pelarut asam sulfat lebih tinggi dibandingkan pada pelarut daun mengkudu sehingga efisiensi yang dihasilkan dengan menggunakan asam sulfat lebih besar dibandingkan larutan daun mengkudu. Hasil penelitian juga menunjukkan peningkatan laju alir pelarut akan menaikkan koefisien perpindahan massa. Sedangkan untuk studi hidrodinamika, kenaikan laju alir pelarut menyebabkan meningkatnya penurunan tekanan di dalam kontaktor membran.

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Evaluation of effectiveness solvent from leaf morinda citrifolia for gas absorption amonia using contactor hollow fiber membrane have been researched. Solvent that used leaf morinda citrifolia with dose 200 gram per liter of water and sulphuric acid 0.1M. For transfer study mass, watchfulness result shows transfer coefficient value mass in solvent sulphuric acid is higher than solvent leaf morinda citrifolia so that efficiency that produced by using sulphuric acid is higher than leaf morinda citrifolia. Also will show rate of flow enhanced solvent will raise transfer coefficient mass. While for hydrodynamics study, rate of flow increase solvent causes the increasing of pressure depreciation in contactor membrane."

"Gas alam Indonesia umumnya mengandung kontaminan uap air, N2, CO2, dan H2S, dengan kadar CO2 dan uap air relatif lebih besar dibandingkan N2 dan H2S, contohnya gas alam Natuna memiliki kandungan CO2 sekitar 70% (berbeda dengan minyak dan gas negara-negara Timur Tengah yang cenderung lebih tinggi kandungan H2S-nya). Selama ini, cara konvensional menyerap CO2 adalah dengan menggunakan kolom absorber-regenerator. Sehingga untuk gas alam yang kandungan CO2nya cukup tinggi meningkatkan biaya untuk proses penghilangan CO2nya. Teknologi membran juga telah diterapkan untuk pemisahan ini.Proses membran menggunakan perbedaan konsentrasi sebagai tenaga penggerak (driving force) untuk memisahkan CO2 dari gas alam. Pemisahan CO2 dari gas alam dengan menggunakan membran telah banyak dikembangkan karena prosesnya yang sederhana, mudah, ramah lingkungan, serta konsumsi energi dan biaya operasional yang rendah. Penelitian ini bertujuan untuk mengevaluasi efektivitas kontaktor membran serat berongga sebagai kontaktor proses penyerapan CO2 dari campuran gas CH4-CO2 dan campuran gas N2-CO2 dengan menggunakan air dari aspek perpindahan massa dan hidrodinamika.Penelitian ini menggunakan dua macam membran polipropilen yang berbeda. Yang pertama, membran yang diproduksi oleh Hoechst Celanese bertipe Celgard X-20 yang berdiameter 0,2 cm dan memiliki pori-pori sebesar 0,1 _m dengan menggunakan modul berdiameter 1,6 cm. dan jumlah serat bervariasi dari 12, 15 dan 18. Sementara yang lainnya adalah membran AKZO yang berdiameter 0,27 cm dan memiliki poripori sebesar 0,2 _m dengan menggunakan modul berdiameter 1,9 cm dan jumlah serat bervariasi dari 10, 15 dan 20.Berdasarkan penelitian koefisien perpindahan massa yang diperoleh berkisar dari 1,15 x 10-5 m/s hingga 9,02 x 10-7 m/s. Dari hasil penelitian, didapat bahwa pada proses absorbsi CO2 ke dalam air menggunakan kontaktor membran serat berongga, koefisien perpindahan massa meningkat seiring dengan meningkatnya laju alir dan menurun dengan meningkatnya jumlah serat dalam dimensi modul yang sama. Koefisien perpindahan massa yang terjadi lebih besar jika menggunakan gas campuran CH4-CO2 dibandingkan gas campuran N2-CO2. Sementara itu dari hasil uji hidrodinamika didapat bahwa dengan meningkatnya jumlah serat dan kecepatan aliran, penurunan tekanan yang terjadi semakin besar. Namun, faktor friksi semakin kecil seiring dengan meningkatnya jumlah serat dan kecepatan aliran.

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Indonesia's natural gas generally contain with water vaporation, N2, CO2, and H2S, with the amount of CO2 and water vaporation relatively higher than the amount of N2 and H2S, as in Natuna's natural gas has the amount of CO2 around 70% (different with the Middle East's oil and gas that more likely to has higher H2S). Up to today, the conventional way to absorb CO2 is by using absorber-regenerator coloum. So that, for the natural gas that has quite high amount of CO2 resulted in big cost of the CO2 elimination process. However, membrane technology is already implemented in this kind of elimination process. Membrane is a blocker between two phase that give selective pathway, so that a particular molecule be able to penetrate the pathway while the other molecule unable to penetrate.

Membrane processing uses the concentration gap as a driving force to separate CO2 from the natural gas. This membrane technique has been widely developed due to its many advantages, such as its simple process, easy, enviromental friendly, and low operational budget with a small number of energy consuming. This research was doing process that contacting CO2-CH4 and CO2-N2 with water by using hollow fiber membrane contactor, varies in many amount of fiber and flow rate of water. Measurement of pH and water temperature and measurement of delta pressure differences in water flow are used in this research.

This research was using two type polypropylene membrane.First, membrane that is produced by Hoechst Celanese bertipe Celgard X-20 with diameter of 0.2 cm and has pore diameter of 0.1 _m. Second, AKZO membrane with diameter of 0.27 cm and has pore diameter of 0.2 _m. This research, flow rate of water varied in 100 lph (liter per hour), 150 lph, 200 lph, 250 lph, 300 lph dan 350 lph.

Based on research, mass transport coefficient is around 1.151 x 10-5 m/s to 9.020 x 10-7 m/s. The result showed that the mass transport is quite high, mass transport coefficient increased inline with flow rate of water and decrease as the amount of fiber was rising up. Moreover, mass transport coefficient was higher by using CH4-CO2 than by using N2-CO2. The hydrodinamics test showed that increasing number of fiber and flow rate resulted in decresing number of delta pressure rate However, the friction factor was shrinking inline with the increasing number of fiber and flow rate."

"This goverment has taken the initiative to launch a national program of converting the use of kerosene to Liquid Propane Gas (LPG) for domestic cooking. This aims to reduce goverment subsidies for gasoline. People are expected to support the national program to convert kerosene to LPG by buying and using LPG for their cooking needs. the purpose of this research is to find out the factors that influence people to buy or use LPG. Specifically, two question will be answered in this research: (1) what is the role of LPG as a cooking fuel option in the household? (2) what factors influence decisious to purchase or use LPG? The sample are 300 Salatiga residents as respondents with a convenience sampling technique and a descriptive statistical analysis applied in the form of calculating frequency distribution and cross tabs. To examine the factors, which influence the decision to buy or use LPG, a regression alaysis is used.The research result reveal that: (1) after conversion program, LPG dominates the use of household cooking energy, (2) age, aducational level of household members, dummy household with kids, household income, access to LPG and frequency of cooking food determine household decisions to buy or use LPG."

"The aim of this study is to evaluate the effects of absorbent flow rate on CO2 absorption through a super hydrophobic hollow fiber contactor. The absorbent used in this study was a physical absorbent, namely a polyethyleneglycol-300 (PEG-300) solution. Meanwhile, the feed gases used in the experiments were pure CO2 and a mixture of 30% CO2 and 70% CH4. Gas absorption using a physical absorbent provides various benefits; for example, it can produce sufficiently high selectivity towards CO2 and it is less corrosive than chemical solvents. Three super hydrophobic hollow fiber contactors, each 6 cm in diameter and 25 cm in lengthconsist of 1000, 3000 and 5000 fibers, respectively, were used in this study. The type ofsuper hydrophobic fiber membrane used was polypropylene-based, with an outer and inner diameter of about 525 and 235 µm, respectively. During the experiments, the absorbent was flowed through the lumen fibers, whilst the feed gas flowed through the shell side of the membrane contactors. The experimental results showed that the mass transfer coefficient, the flux, and the absorption efficiency increased, but the CO2 loading decreased, with increasing absorbent flow rate in the membrane contactor. Meanwhile, it was found that an increase in the number of fibers in the membrane contactor, in general, will increase the absorption efficiency and the CO2 loading, but will decrease the overall mass transfer coefficient and the flux."