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Shaharin A. Sulaiman
"Currently the world’s second largest palm oil producer Malaysia produces a large amount of oil palm biomass each year. Although some oil palm parts and derivatives like empty fruit bunch and fibre have been commercialized as fuel, less attention has been given to oil palm fronds (OPF). Initial feasibility and characterization studies of OPF showed that it is highly feasible as fuel for gasification to produce high value gaseous fuel or syngas. This paper discusses the experimental gasification attempt carried out on OPF using a 50 kW lab scale downdraft gasifier and its results. The conducted study focused on the temperature distributions within the reactor and the characteristics of the dynamic temperature profile for each temperature zones during operation. An average pyrolysis zone temperature of 324oC and an average oxidation zone temperature of 796oC were obtained over a total gasification period of 74 minutes. A maximum oxidation zone temperature of 952oC was obtained at 486 lpm inlet air flow rate and 10 kg/hr feedstock consumption rate. Stable bluish flare was produced for more than 70% of the total gasification time. Similar temperature profile was obtained comparing the results from OPF gasification with that of woody biomass. Furthermore, the successful ignition of the syngas produced from OPF gasification ascertained that OPF indeed has a higher potential as gasification feedstock. Hence, more detailed studies need to be done for better understanding in exploiting the biomass as a high prospect alternative energy solution. In addition, a study of the effect of initial moisture content of OPF feedstock on the temperature distribution profile along the gasifier bed showed that initial moisture content of feedstock in the range of 15% gives a satisfactory result, while experiments with feedstock having higher moisture content resulted in lower zone temperature values."
Depok: Faculty of Engineering, Universitas Indonesia, 2012
UI-IJTECH 3:1 (2012)
Artikel Jurnal  Universitas Indonesia Library
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Alfian Rivaldi Nugraha
"Detox sludge merupakan salah satu sumber mineral yang memiliki potensial yang besar untuk dilakukan proses pengolahan dan pemurnian. Salah satu metode untuk proses pengolahan detox sludge yaitu dengan cara proses reduksi karbotermik. Proses karbotermik sering digunakan untuk mereduksi suatu mineral, dimana proses reduksi karbotermik membutuhkan reduktor untuk mereduksi unsur-unsur lain yang terdapat pada detox sludge. Reduktor yang biasa digunakan pada proses reduksi karbotermik adalah batubata dan kokas. Tetapi penggunaan batubara memiliki banyak efek negatif bagi lingkungan, maka dari itu pada penelitian ini reduktor yang digunakan adalah biomassa, yaitu cangkang kelapa sawit yang dipanaskan hingga suhu 900˚C agar menjadi arang. Dalam penelitian ini digunakan detox sludge yang berasal dari proses pengolahan emas dan tembaga dan cangkang kelapa sawit berasal dari Palangkaraya, Kalimantan Tengah. Detox sludge dan cangkang kelapa sawit di preparasi terlebih dahulu sebelum dilakukan proses reduksi karbotermik. Tujuan dari penelitian ini adalah untuk mengetahui pengaruh variasi waktu reduksi detox sludge, dengan rasio massa dan temperature yang tetap. Variasi waktu reduksi yang dilakukan dalam penelitian ini adalah 30 menit, 60 menit, dan 120 menit. Seluruh sampel diuji pada suhu 900˚ dan rasio massa 1:2 ( detox sludge: cangkang kelapa sawit) yang dimasukan kedalam krusibel keramik dan dilakukan reduksi karbotermik di dalam tungku. Hasil XRD menyatakan bahwa terjadinya penghilangan puncak calcite yang menandakan sudah terjadi proses reduksi pada calcite dan adanya penambahan senyawa yaitu alumina. Hasil XRF menunjukan bahwa pada waktu reduksi selama 90 menit merupakan waktu optimum karena didapatkan %recovery disemua kandungan paling tinggi diantara variasi waktu lainnya.

Detox sludge is a mineral source that has great potential for processing and refining. One of the method for the processing of detox sludge is a carbothermic reduction process. Carbothermic processes are often used to reduce a mineral, where the carbothermic reduction process requires a reducing agent to reduce other elements present in detox sludge. Reductors that are commonly used in the carbothermic reduction process are coal and coke. But the use of coal has many negative effects on the environment, therefore in this study the reducing agent used is biomass, namely pal kernel shells. In this study, detox sludge originating from the processing of gold and copper and palm kernel shells from Palangkaraya, Central Kalimantan. Detox sludge and palm kernel shells are prepared first before carrying out the carbothermic reduction process. The purpose of this study was to determine the effect of variations in the reduction time of detox sludge, with a fixed ratio of mass and temperature. The reduction time variations in this study were 30 minutes, 60 minutes, and 120 minutes. All samples were tested at a temperature of 900˚ and a mass ratio of 1: 2 (detox sludge: palm kernel shell) which was inserted into the ceramic crucible and the carbothermic reduction was carried out in the furnace. After the reduction process is complete the detox sludge will be separated from the oil palm shell and carried out by XRD and XRF testing to determine the optimum time for the carbothermic reduction process. XRD results state that the occurrence of calcite peak removal that indicates there has been a reduction process in calcite and the addition of compounds namely alumina. XRF results show that at a reduction time of 90 minutes is the optimum time because %recovery is obtained in all the highest content among other time variations."
Depok: Fakultas Teknik Universitas Indonesia, 2020
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UI - Skripsi Membership  Universitas Indonesia Library
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Nindita Larasati
"ABSTRACT
An extensive search of clean energy is the main drive for hydrogen production technology advancements. Hydrogen is an appealing energy source as an alternative to fossil fuels due to its carbon neutral lifecycle, making it more environmental friendly. Gasification technology is one of the most sought-after method of hydrogen production due to its efficiency and flexibility of the feedstock options. This research intends to bridge the gap where current literature is lacking by presenting a thermodynamic equilibrium model through simulation of non-catalytic steam gasification of oil palm kernel shell using Aspen Plus v10.0 software. A couple of operating parameters that have adverse effect on gasification efficiency, namely temperature of gasifier and steam-to-biomass (S/B) ratio were investigated in this study. The simulation results show that the optimum operating condition to get the highest hydrogen yield is obtained at temperature of 800 oC and S/B ratio of 1.0 wt/wt. Temperature enhances hydrogen content up to 82.54 vol% at the range of 750 to 800 oC while the highest margin of the incline of hydrogen composition is observed from 0.5 to 1.0 wt/wt at  80.90 vol% to 82.24 vol%. Based on the results, temperature has more impact on hydrogen yield compared to S/B ratio due to endothermic reactions being favored at high temperature such as water gas reaction and steam methane reforming reaction. Although hydrogen yield increases with an increase in S/B ratio, it is not beneficial to introduce too much excess steam since it does not have great impact to hydrogen yield with less than 1% increase per kg steam introduced. Different feedstocks were used as comparison to test the applicability of the model. It is found that pine sawdust and oil palm kernel shell are proven to be the most suitable feedstock as they give high hydrogen yield and high hydrogen content in syngas due to high volatile matter and fixed carbon content in addition to low moisture and ash content compared to municipal solid wastes (MSW), green wastes, food wastes, and straw.

ABSTRAK
Penelitian mengenai energi bersih adalah dorongan utama dari kemajuan teknologi produksi hidrogen. Hidrogen adalah sumber energi yang menarik sebagai alternatif dari bahan bakar fosil dikarenakan oleh siklus yang netral dari karbon, menjadi lebih ramah lingkungan. Teknologi gasifikasi adalah salah satu metode yang paling terkemuka akibat efisiensi dan fleksibilitas pemilihan bahan baku. Penelitian ini bertujuan untuk menjembatani kesenjangan dimana literatur terkini kurang mendalami dengan mengajukan model ekuilibrium termodinamika melalui simulasi gasifikasi uap non-katalis dengan bahan baku cangkang kelapa sawit menggunakan perangkat lunak Aspen Plus versi 10.0. Beberapa parameter operasi yang berpengaruh terhadap efisiensi gasifikasi seperti temperatur dari reaktor dan rasio uap-biomassa telah diteliti dalam studi ini. Hasil simulasi menunjukkan kondisi operasi optimal untuk mendapatkan hasil produksi hidrogen tertinggi dicapai pada temperatur 800 C dan rasio uap-biomass 1.0 wt/wt. Temperatur menaikkan komposisi hidrogen sehingga 82.54 vol% pada kisaran 750 sampai 800 C sedangkan margin kenaikan komposisi hidrogen paling tinggi didapat dari 0.5 sampai 1.0 wt/wt dari 80.90 vol% menjadi 82.24 vol%. Berdasarkan dari hasil, temperatur memberikan dampak yang lebih besar dibandingkan rasio uap-biomass diakibatkan oleh reaksi endotermik yang lebih spontan pada temperatur tinggi seperti reaksi air-gas dan reaksi reformasi metana dan uap. Walaupun hasil hidrogen meningkat seiring kenaikan dari rasio uap-biomass, memasukkan uap terlalu banyak tidak efisien sebab efeknya tidak signifikan dengan kenaikan kurang dari 1% per kilogram uap tambahan. Bahan baku berbeda digunakan sebagai perbandingan untuk menguji penerapan model ini. Hasil menunjukkan bahwa serbuk kayu pinus (pine sawdust) dan cangkang kelapa sawit terbukti menjadi bahan baku yang paling cocok untuk gasifikasi karena menghasilkan hasil dan komposisi hidrogen yang paling tinggi disebabkan oleh konten zat mudah menguap dan karbon tetap yang tinggi dengan konten kelembaban dan abu yang rendah dibandingkan limbah padat, limbah hijau, limbah makanan, dan jerami."
2019
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UI - Skripsi Membership  Universitas Indonesia Library
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Ardhito Triahmadi Gunawan
"ABSTRAK
Penelitian ini membahas tentang proses pembuatan keputusan pemerintah Malaysia untuk mengembangkan komoditas biodiesel sawitnya dengan membuat kebijakan National Biofuel Policy NBP pada tahun 2006. Penelitian ini menggunakan metode kualitatif dengan data sekunder. Temuan pada penelitian ini menunjukkan bahwa pembuatan keputusan tersebut didasarkan kepada dua bentuk pengaruh yang ada, yaitu social learning dan external inducement. Kedua bentuk pengaruh tersebut telah berhasil mendorong Malaysia dalam membuat keputusannya dan mulai merumuskan kebijakan NBP pada 2005 hingga terbentuk pada tahun 2006. Pada akhirnya, kebijakan ini cukup berhasil dalam mewujudkan tujuan awal dibuatnya. Kebijakan NBP berhasil mendorong adanya pembentukan standar biodiesel sawit yang kemudian setara dengan standar biodiesel internasional. Kebijakan NBP juga berhasil mendorong ekspor biodiesel sawit, terlebih lagi setelah standar internasional tersebut tercapai.

ABSTRACT
This research discussed the Malaysian government decision making process in developing its palm oil biodiesel commodity by formulating the National Biofuel Policy NBP in 2006. To analyze it, qualitative method and secondary data were used . The findings on this research showed that the decision making process is based on two forms of influences, namely social learning and external inducement. Those influences succeeded in affecting Malaysia rsquo s decision making process, which led Malaysia to formulating NBP in 2005 to its completion. In the end, the policy is successful enough in accomplishing its initial goals. NBP succeeded in pushing the formation of a palm oil biodiesel standard which is on compliance with the international biodiesel standard. NBP also succeeded in promoting palm oil biodiesel export, especially after international standard had been met.
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2017
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UI - Skripsi Membership  Universitas Indonesia Library
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Azhar Aditya Rahman
"Produksi komoditas sawit terbesar di dunia. Proses pengolahan sawit menghasilkan limbah tandan kosong sawit (TKS) dengan kisaran 20-23 % dari berat tandan buah segar. TKS merupakan biomassa lignoselulosa, sehingga mengandung selulosa, hemiselulosa, dan lignin. Pemanfaatan selulosa dan hemiselulosa membutuhkan praperlakuan untuk membuka ikatan lignin yang menyelubungi keduanya. Pada penelitian ini, akan dilakukan praperlakuan tandan kosong sawit dengan metode amonium hidroksida berbantuan gelombang mikro. TKS diberi praperlakuan fisika dengan pencucian dan penggilingan hingga mencapai ukuran 30 mesh. Selanjutnya TKS dimasukkan ke dalam gelas kimia dan diberikan larutan amonium hidroksida dengan rasio padat-cair 1:10 dan konsentrasi yang divariasikan (7,5; 10; 12,5%). Campuran dimasukkan ke dalam microwave dengan variasi daya 280, 560, dan 840 W, serta variasi waktu 3, 6, dan 9 menit. Sampel dikarakterisasi dengan uji lignin Klason, SEM, dan XRD.
Hasil yang diperoleh kemudian dioptimasi dengan metode Response Suface Methodology dengan pengaplikasian model Box-Behnken. Hasil mikrograf SEM menunjukkan perekahan dan pembentukan pori-pori pada mikrostruktur TKS. Hasil difraktogram XRD menunjukkan penurunan kristalinitas selulosa TKS sebesar 36,38%. Delignifikasi tertinggi diperoleh pada daya 840 Watt, konsentrasi 10%, dan waktu radiasi 9 menit, yaitu sebesar 63,32%. Hasil uji statistik dan model yang diperoleh menunjukkan efek linear pada faktor daya dan konsentrasi, sedangkan faktor waktu radiasi menunjukkan efek kuadratik. Titik optimum yang diperhitungkan terdapat pada daya 839,190 Watt, konsentrasi 12,427%, dan waktu radiasi 8,762 menit, dengan prediksi delignifikasi sebesar 79,514%.

Indonesia is an agricultural country with the largest production of palm oil commodities in the world. The palm oil processing will produce oil palm empty fruit bunches (OPEFB) waste with a range of 20-23% of the weight of fresh fruit bunches. OPEFB is a lignocellulosic biomass, which contain cellulose, hemicellulose, and lignin. The use of cellulose and hemicellulose requires pretreatment to open the lignin bond that covers those materials. In this study, pretreatment of oil palm empty bunches using microwave-assisted ammonium hydroxide method will be carried out. The OPEFB was given a physical pretreatment by washing and grinding to reach a size of 30 mesh. After that, the OPEFB was put into a beaker and mixed with ammonium hydroxide solution with a solid-liquid ratio of 1: 10 under varied concentration (7.5; 10; 12.5%). The mixture was put into a microwave under power variation of 280, 560, and 840 W, with time variation of 3, 6, and 9 minutes. The samples were then characterized by Klason lignin, SEM, and XRD tests.
The results obtained were then optimized using Response Suface Methodology with the application of the Box-Behnken Model. The SEM micrograph showed openings and formation of pores in the OPEFB microstructure. The XRD diffractogram showed a 36.38% decrease in cellulose crystallinity. The highest delignification was obtained at power of 840 Watts, concentration of 10%, and time of 9 minutes, which was 63.32%. The statistical test and the model that was obtained showed a linear effect on power and concentration factors, while the radiation time factor showed a quadratic effect. The calculated optimum point was obtained at power of 837.190 Watts, concentration of 12.427%, and time of 8.762 minutes, with the predicted delignification of 79.514%.
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Depok: Fakultas Teknik Universitas Indonesia, 2019
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Muhammad Ismail Bagus Setyawan
"Gasifikasi merupakan salah satu thermal-treatment yang dapat dilakukan untuk mengolah biomassa menjadi energi. Syngas merupakan produk utama dari proses gasifikasi, tetapi gasifikasi juga menghasilkan tar yang dapat mengganggu kesehatan manusia, lingkungan maupun peralatan berbahan bakar syngas. Untuk mengurangi kandungan tar, dilakukan modifikasi dalam gasifier dengan menambahkan inlet udara tambahan. Pendekatan model numerik yang digunakan di penelitian ini adalah pemodelan representatif partikel. Dalam penelitian ini, terdapat 2 model yang diusulkan untuk mengkarakterisasi gasifier: gasifier dibagi menjadi 2 kuasi-reaktor (model 1), dan inlet udara primer dan sekunder diasumsikan menjadi satu inlet udara (model 2). Variabel bebas yang digunakan adalah kondisi awal region konveksi campur dan equivalence ratio (ER). Dari hasil penelitian ini, fenomena yang dapat ditangkap di model 1 adalah persebaran temperatur, komposisi partikel, perubahan komposisi syngas terhadap ER dan komposisi tar dalam syngas, sedangkan fenomena yang dapat ditangkap di model 2 adalah komposisi syngas dengan standar deviasi 8,51. Penambahan densitas inlet udara yang berubah terhadap temperatur di kondisi awal region konveksi campur cocok digunakan untuk permodelan gasifier. Kandungan CO dan H2 mengalami peningkatan sedangkan kandungan CO2, CH4 dan H2O mengalami penurunan saat ER dinaikkan. Hasil penelitian menunjukkan model 1 perlu dievaluasi lebih lanjut agar dapat menghasilkan komposisi syngas yang lebih akurat.

Gasification is one of thermal treatments that could convert biomass into energy. Syngas is the main product of gasification, but gasification also produces tar that could harm human health, environment, and syngas-fuelled equipment. To decrease tar content in syngas composition, modification is done to gasifier by adding secondary air inlet. The numerical approach used in this research was representative particle model (RPM). There were 2 proposed models to characterize gasifier: gasifier was divided into 2 quasi-reactors (model 1), and air inlets were assumed as just one air inlet (model 2). The independent variables were initial conditions of mixed convection region, and equivalence ratios (ER). The results showed model 1 could simulate gasification phenomena, as in temperature distribution, particle composition, change in syngas composition to ER and tar content, while model 2 could simulate the phenomenon as in syngas composition with standard deviation of 8.51. The addition of temperature-dependent air inlet density in gas species mass balance was found suitable for modelling gasifier. The research found CO and H2 contents were increasing, while CO2, CH4 and H2O contents were decreasing as the increase of ER. The research concludes model 1 needs to be further evaluated to approach syngas composition more accurately."
Depok: Fakultas Teknik Universitas Indonesia, 2020
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UI - Tesis Membership  Universitas Indonesia Library
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Alya Hafiza Vivadinar
"Pada penelitian ini, dilakukan analisis aspek teknis, lingkungan, dan ekonomi pada proses produksi Hydrogenated Vegetable Oil (HVO) dengan hidrogen dari Steam Methane Reforming (SMR), Gasifikasi Biomassa (BG), Elektrolisis dengan Pembangkit Listrik Panas Bumi (GEO-E), dan Elektrolisis dengan Pembangkit Listrik Panel Surya (PV-E). Tujuan dari penelitian ini adalah mendapatkan efisiensi energi, faktor emisi, serta biaya produksi HVO dari teknologi hidrogen yang berbeda-beda. Seluruh teknologi disimulasikan menggunakan Aspen Plus® dengan fluid package Peng-Robinson. HVO diproduksi menggunakan dua reaktor, yaitu reaktor hydrotreating dan reaktor hidroisomerisasi dan menghasilkan tiga produk, yaitu HVO, green naphtha, dan bio-jet fuel. Proses produksi hidrogen menggunakan BG menggunakan bahan baku empty fruit bunch (EFB). Sedangkan pasokan listrik untuk elektrolisis didapat dari GEO-E dengan sitem kombinasi ORC dan Flash. Pasokan listrik untuk elektrolisis dengan PV-E dilengkapi dengan baterai. Analisis teknik dilakukan dengan menghitung efisiensi energi produksi HVO. Analisis ekonomi dilakukan dengan menghitung biaya produksi HVO dengan metode Levelised Cost of Energy (LCOE). Analisis lingkungan dilakukan dengan menghitung emisi CO2-e dengan metode Life Cycle Analysis. Hasil analisis memperlihatkan bahwa produksi HVO dengan efisiensi terbaik didapat dari hidrogen hasil SMR dengan efisiensi 55,67%, yang diikuti oleh BG (31,47%), PV-E (9,34%), dan GEO-E (7,89%). LCOE terendah juga masih membutuhkan produksi hidrogen dari SMR dengan LCOE sebesar $15,79/GJ-HVO, yang diikuti oleh BG ($16,37/GJ-HVO), GEO ($22,83/GJ-HVO), dan PV ($27,29/GJ-HVO). Akan tetapi, produksi HVO yang paling ramah lingkungan menggunakan GEO-E sebagai teknologi produksi hidrogen dengan faktor emsisi sebesar 1,63 kgCO2-e/kg HVO, yang diikuti oleh PV-E (1,86 kgCO2-e/kg HVO), SMR (5,57 kgCO2-e/kg HVO), dan BG (16,52 kgCO2-e/kg HVO).

Study is done from the perspective of technicality, environment, and economical for Hydrogenated Vegetable Oil (HVO) production with hydrogen from Steam Methane Reforming (SMR), Biomass Gasification (BG), Geothermal Electrolysis (GEO-E), and Solar Photovoltaic Electrolysis (PV-E). The purpose of this study is to evaluate the energy efficiency, emission factors, and cost production of HVO production from various hydrogen production technologies, mentioned above. Every production technology is simulated using Aspen Plus® using the Peng-Robinson fluid package. HVO is produced by two reactors, which are hydrotreating reactor and hydroisomerisastion reactor. The process produces three main products, HVO, green naphtha, dan bio-jet fuel. Feedstock to produce hydrogen from BG is Empty Fruit Bunch (EFB). Electricity production via geothermal for electrolysis uses combination of Organic Rankine Cycle (ORC) and flash system. While the electricity produced using Solar Photovoltaic is equipped with battery. Technical analysis is done by calculating the energy efficiency from overall system energy flow. Production cost is calculated using the Levelised Cost of Energy (LCOE) to analyse the economical aspect. CO2-e emission is determined using the Life Cycle Analysis (LCA) method to analyse the environmental aspect. Study has shown that HVO production with SMR as the hydrogen production technology has the highest energy efficiency (55,67%), which then followed by BG (31,47%), PV-E (9,34%), and GEO-E (7,89%). The lowest LCOE can be obtained if the hydrogen is obtained from SMR aswell (15,78/GJ-HVO), which is followed by BG ($16,37/GJ-HVO), GEO ($22,83/GJ-HVO), and PV ($27,29/GJ-HVO). However, HVO production with the lowest emission factor is equipped with GEO-E (1,63 kgCO2-e/kg HVO), which followed by PV-E (1,86 kgCO2-e/kg HVO), SMR (5,57 kgCO2-e/kg HVO), and BG (16,52 kgCO2-e/kg HVO)."
Depok: Fakultas Teknik Universitas Indonesia, 2020
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UI - Skripsi Membership  Universitas Indonesia Library
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Ismail Fatih Al-Faruqi
"

Pelepah Kelapa Sawit (OPF) merupakan salah satu limbah pertanian Indonesia yang melimpah dengan berbagai potensi yang menjanjikan. Kandungan holoselulosa yang tinggi pada minyak pelepah sawit dapat dimanfaatkan untuk memproduksi gula pereduksi dan bahan kimia platform. Gula pereduksi diperoleh melalui pretreatment (delignifikasi) dan hidrolisis enzimatik. Makalah ini melaporkan pretreatment pelepah kelapa sawit menggunakan pretreatment hidrotermal dengan beberapa jenis larutan buffer asam (fosfat, asetat, dan sitrat) untuk meningkatkan produksi glukosa dan xilosa. Studi dilakukan dengan membandingkan kinerja pelarut hidrotermal menggunakan air dan larutan penyangga asam terhadap degradasi lignin dan OPF yang dihidrolisis secara enzimatis pada kondisi operasi yang stabil. Kondisi operasi pretreatment yang optimal ditentukan dengan memvariasikan waktu tinggal dan suhu pretreatment. Larutan penyangga sitrat menunjukkan kemampuan degradasi lignin terbaik pada suhu 150OC dan waktu tinggal 40 menit. Hasil recovery glukosa dan xilosa yang diperoleh adalah 24,76 g/g dan 3,93 g/g. Penggunaan larutan buffer asam menunjukkan peningkatan hasil recovery glukosa sebesar 88,31% dibandingkan pretreatment hidrotermal konvensional, namun hasil recovery xilosa mengalami penurunan sebesar 17,29%.


Oil Palm Fronds (OPF) are one of Indonesia's abundant agricultural wastes, with many promising potentials. The high holocellulose content in the oil palm frond can be used to reduce sugars and platform chemicals. Reducing sugar is obtained through pretreatment (delignification) and enzymatic hydrolysis. This paper reports on oil palm frond pretreatment using hydrothermal pretreatment with several types of acid buffer solutions (phosphoric, acetic, and citric) to increase the production of glucose and xylose. The study was conducted by comparing the performance of hydrothermal solvents using water and acid buffers against lignin degradation and enzymatically hydrolyzed OPF under stable operating conditions. The optimal pretreatment operating conditions were determined by comparing the residence time and pretreatment temperature. Buffer Citrate showed the best lignin degradation ability at temperature 150OC and residence time 40 minute. The yields recovery of glucose and xylose obtained were 24.76 g/g and 3.93 g/g. Using an acid buffer solution showed an increase in glucose yield recovery of 88.31% compared to conventional hydrothermal pretreatment, but the yield recovery of xylose decreased by 17.29%.

"
Depok: Fakultas Teknik Universitas Indonesia, 2023
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Raka Kautsar Lahia
"Biomass gasification is a process to convert biomass to be a combustible gas. That combustible gas named syngas later will be mixed with air or oxidator inside the gas burner to get appropiate mixing or air and fuel then could be produce optimum flame after being ignited. Gas burner that could mix the fuel and the air appropiately needed to get the optimum flame. Swirl vane is a part of gas burner that has a function to make a perfect mixing of air and fuel.The problem is the optimum number of swirl vane on gas burner still unknown. Experiment of three kinds of gas burner with different number of swirl vane; six ,eight , and ten swirl vanes done in this thesis with an objective to find out the most optimum number of swirl vane on gas burner.
The results of experiment on variation of swirl vane number on gas burner is gas burner with 8 swirl vanes has the highest average flame temperature (795°C), also the highest heat release rate (11,15 kJ/s). Higher the flame temperature result in higher heat release rate. Combustion efficiency on gas burner with 8 swirl vanes is the best with 85,5%, then gas burner with 10 swirl vanes with 85,1%, and the last gas burner with 6 swirl vanes with 83,1%. Those result indicate that gas burner with 8 swirl vanes could make the best internal recirculation zone (IRZ) so that the mixing of air and fuel in the gas burner with 8 swirl vanes becomes more perfect than the other gas burner result in the most perfect combustion process."
Depok: Fakultas Teknik Universitas Indonesia, 2010
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UI - Skripsi Open  Universitas Indonesia Library
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Mustakim
"The largest region that produces oil palm in Indonesia has an important role in improving the welfare an economy of the society. Oil palm production has increased significantly in Riau Province in every period. To determine the production development for the next few years, we proposed a prediction of the production results. The dataset were taken to be the time series data of the last 8 years (2005-2013) with the function and benefits of oil palm as the parameters. The study was undertaken by comparing the performance of Support Vector Regression (SVR) method and Artificial Neural Network (ANN). From the experiment, SVR resulted the better model compared to the ANN. This is shown by the correlation coefficient of 95% and 6% for MSE in the kernel Radial Basis Function (RBF), whereas ANN resulted only 74% for R2 and 9% for MSE on the 8th experiment with hidden neuron 20 and learning rate 0,1. SVR model generated predictions for next 3 years which rose 3%-6% from the actual data and RBF model predictions
Daerah penghasil kelapa sawit terbesar di Indonesia mempunyai peranan penting dalam peningkatan kesejahteraan dan ekonomi masyarakat. Produksi kelapa sawit mengalami peningkatan yang signifikan di Provinsi Riau dalam setiap kurun waktu, untuk menentukan perkembangan produksi beberapa tahun ke depan, kami mengusulkan suatu prediksi dari hasil produksi. Dataset yang diambil adalah data time series dari data yang diperoleh selama 8 tahun terakhir (2005-2013) dengan fungsi dan manfaat kelapa sawit sebagai parameter. Dalam implementasinya peramalan dilakukan dengan membadingkan kinerja metode Support Vector Regression (SVR) dan Artificial Neural Network (ANN). Dari percobaan, SVR menghasilkan model terbaik dibandingkan dengan ANN yaitu ditunjukkan dengan koefisien korelasi sebesar 95% dan MSE 6% pada kernel Radial Basis Function (RBF), sedangkan ANN hanya menghasilkan R2 sebesar 74% dan MSE 9% pada percobaan ke-8 dengan hidden neuron 20 dan learning rate 0,1. SVR model menghasilkan prediksi untuk 3 tahun kedepan yang memiliki kenaikan antara 3%-6% dari data aktual dan prediksi model RBF"
Riau: Faculty of Science and Technology, 1Information System Department UIN Sultan Syarif Kasim Riau, 2016
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