Hasil Pencarian  ::  Simpan CSV :: Kembali

"Tert amyl methyl ether (TAME) adalah senyawa aditif oksigenat dari golongan eter yang dapat diproduksi dengan distilasi reaktif. Masalah utama dari penggunaan kolom distilasi reaktif adalah adanya kombinasi sistem reaksi dan pemisahan dalam satu kolom sehingga menghasilkan sistem yang sangat kompleks akibat dari interaksi setiap variabel proses yang saling mempengaruhi satu dengan yang lain. Oleh karena itu, dibutuhkan jenis pengendalian dengan kinerja yang dapat menjaga kondisi operasi tetap stabil dan mampu menangani gangguan proses dengan baik seperti Model Predictive Control (MPC). Pada penelitian ini, dilakukan simulasi pengendalian proses produksi TAME yang menggunakan kolom distilasi reaktif berskala pabrik dengan MPC dan proportional integral (PI) pada simulator HYSYS V11. Model untuk mewakili kondisi dinamis pada sistem ini didekati dengan model FOPDT. Untuk mendapatkan hasil yang optimal parameter MPC di-tuning menggunakan metode fine-tuning, yang kemudian dibandingkan kinerjanya dengan pengendali PI yang di­-tuning menggunakan autotuner yang sudah tersedia pada simulator HYSYS. Hasil simulasi menunjukan bahwa MPC memberikan hasil yang lebih baik dibanding pengendali PI dengan peningkatan kinerja pengendalian sebesar 54.4% dalam uji pelacakan setpoint. Selain itu, uji gangguan pun dilakukan dengan meningkatkan laju alir umpan kolom distilasi reaktif sebesar 10%. Pada uji gangguan MPC memberikan respon yang lebih cepat dan stabil sehingga menghasilkan peningkatan kinerja pengendalian sebesar 64.4% dibanding pengendali PI.......Tert amyl methyl ether (TAME) is an ether used as oxygenated fuel additive that can be synthesized using reactive distillation. The major problem with the use of reactive distillation is the existence of the combination of reaction and separation on a single column that makes the reactive distillation process become very complex systems due to its interaction among process variables. Therefore, it is very important to use the types of control methodologies that can stabilize the operating condition and provide satisfactory control performance due to the complexity of the reactive distillation process dynamics such as model predictive control (MPC). In this study, a simulation of plantwide control by MPC and PI for TAME production is investigated in HYSYS V11. In this research, the dynamics model representing the process was approached by the first order plus dead time (FOPDT) model. MPC was tuned by fine-tuning method, meanwhile the PI controller was tuned by autotuner that is available in HYSYS. The results show that MPC can produce an improvement in setpoint tracking test by 54.4% compared to the PI controller. A disturbance of 10% increases in the feed flow rate of reactive distillation was done to see the controller responses. MPC has faster dan more stable responses than the PI controller and 64.4% improvement was produced by MPC compared to the PI controller."

"ABSTRAKBioethanol saat ini banyak dikembangkan untuk penggunaan bahan bakar kendaraan bermotor. Pemanfaatan low grade bioethanol merupakan awal mula penelitian ini dilakukan. Berawal dari pembuatan compact distillator pada mesin SI karburator untuk memperoleh high grade bioethanol dengan memanfaatkan gas buang sampai pada penelitian terbaru mengenai penggunaan zat aditif yang dicampurkan pada bahan bakar ethanol dengan bensin untuk mendapatkan performa dan emisi yang lebih baik. Pengujian dilakukan pada mesin SI 125cc pada engine dyno dengan menggunakan 7 variasi bahan bakar diantaranya, E0, E5, E10, E15, E5 aditif, E10 aditif, dan E15 aditif. Hasil pengujian diperoleh bahwa penambahan ethanol umumnya dapat meningkatkan performa motor uji yang dihasilkan, dan dengan penambahan zat aditif oxygenated cyclohexanol pada beberapa variasi bahan bakar dihasilkan kenaikan torsi dan daya yang dihasilkan. Sama halnya dengan performa, emisi gas buang CO dan HC pun mennurun akibat pengunaan ethanol sebagai campuran bahan bakar, dan sebaliknya nilai CO2 meningkat oleh karena molekul ndash;OH yang terkandung dalam campuran bahan bakar dengan aditif akan bereaksi dengan CO. CO2 juga dinilai sebagai salah satu indikator pembakaran yang sempurna. Penelitian ini bertujuan untuk melihat pengaruh zat aditif terhadap performa dan emisi gas buang yang dihasilkan oleh motor uji.

---

ABSTRACTBioethanol is currently widely developed for the use of vehicle fuel. Utilization of low grade bioethanol is the beginning of this research conducted. Starting from the manufacture of compact distillator on carburetor SI engine to obtain high grade bioethanol by utilizing exhaust gas up to the latest research on the use of additives in fuel mixture ethanol and gasoline to get better performance and emission gas. The test was performed in a 125 cc SI engine on engine dynamometer using 7 variants of fuel, E0, E5, E10, E15, E5 adfitive, E10 additive, and E15 additive. The results obtained that the addition of ethanol can generally improve the performance, and with the addition of oxygenated cyclohexanol additive in some variations of fuel produces increased torque and power generated. Same with performance, CO, and HC exhaust emissions are reduced due to the use of ethanol as a fuel mixture, and the value of CO2 increases because the ndash OH molecules contained in the fuel mixture with the additive will react with CO. CO2 is also rated as one of the perfect burning indicators. This study aims to see the effect of additives on the performance and exhaust emission produced by the motor test."

"Bio-oil fraksi non-oksigenat memiliki kandungan alkena yang tinggi hal tersebut menyebabkan tingginya ignition delay time dan nilai kalor yang rendah jika dibandingkan dengan bahan bakar diesel komersial. Reaksi hidrogenasi diperlukan sebagai upgrading Bio-oil fraksi non-oksigenat agar dapat memiliki karakteristik mendekati bahan bakar diesel komersial. Tujuan dari penelitian ini adalah menentukan efek kecepatan putar impeller tipe flat blade turbine terhadap karakteristik biofuel produk upgrading Bio-oil fraksi non-oksigenat. Parameter yang dinilai mencakup kandungan ikatan rangkap, branching index, viskositas dan nilai kalor. Investigasi dilakukan terhadap kecepatan putar pengaduk reaksi hidrogenasi pada 200 s.d. 500 rpm dengan rentang 100 rpm. Kemudian dianalisis dengan menggunakan metode FTIR, GC-MS, H-NMR, dan viskometer. Penggunaan self-inducing impeller diharapkan dapat menghemat penggunaan gas hidrogen. Dari hasil penelitian ditemukan bahwa penggunaan self-inducing impeller berhasil mengkonveksi gas hidrogen ke dalam fasa liquid namun tanpa memerlukan suplai hidrogen yang kontinu sehingga penggunaannya lebih hemat. Peningkatan kecepatan putar pengaduk pada reaksi hidrogenasi menyebabkan peningkatan tingkat hidrogenasi Bio-oil untuk range 200 s.d. 400 rpm dan sedikit penurunan pada kecepatan putar 500 rpm karena terbentuknya vortex kearah posisi impeller. Biofuel pada kecepatan putar 400 rpm yang paling mendekati diesel komersial ditinjau dari HHV dan viskositas. Berdasarkan parameter branching index maka biofuel pada kecepatan putar 200 rpm yang paling mendekati diesel komersial.......Bio-oil non-oxygenate fraction has a high alkene content which causes high ignition delay time and low heating value when compared to commercial diesel fuel. Hydrogenation reaction is needed as upgrading process for non-oxygenate fraction Bio-oil in order to have the characteristics close to commercial diesel fuel. The purpose of this study is to determine the effect of the rotating speed of the flat blade turbine type impeller on the biofuel characteristics from upgrading process. The parameters assessed include the double bond content, branching index, viscosity and heat value. Investigations were carried out on the rotational speed of the hydrogenation reaction stirrer at 200 s.d. 500 rpm with a range of 100 rpm. Then analyzed using FTIR, GC-MS, H-NMR, and viscometer methods. The use of self-inducing impeller is expected to save the use of hydrogen gas. From the results of the study it was found that the use of self-inducing impeller succeeded in converting hydrogen gas into the liquid phase but without the need for a continuous supply of hydrogen so that it is more efficient. Increasing the stirring speed of the stirrer in the hydrogenation reaction causes an increase in the extent of hydrogenation for the range of 200 s.d. 400 rpm and a slight decrease in the rotational speed of 500 rpm due to the formation of vortex towards the impeller position. Biofuel at a rotational speed of 400 rpm which is most close to commercial diesel when viewed from HHV and viscosity. Based on the branching index parameters the biofuel at the rotational speed of 200 rpm which is the closest to commercial diesel. "

"ABSTRACTBahan bakar fosil menjadi salah satu kebutuhan utama manusia modern, terutama untuk kendaraan bermotor. Namun, kekurangan bahan bakar fosil memunculkan berbagai alternatif, salah satunya adalah bioetanol. Bioetanol memiliki Angka RON nilai Oktan lebih tinggi dibanding BBM sehingga dapat meningkatkan performa mesin. Namun, penggunaan bioetanol masih terbatas pada pencampuran dengan bahan bakar fosil pada persentase tertentu. Bioetanol yang digunakan merupakan bioetanol fuel grade dengan kadar air dibawah 0,1. Selain meningkatkan performa, penggunaan bioetanol dapat menghasilkan pembakaran yang lebih sempurna sehingga menghasilkan emisi yang lebih baik. Selain bioetanol, solusi lain dalam mengurangi emisi sekaligus memperkecil nilai COV Coefficient of Variation pada mesin adalah penambahan zat aditif Oxygenate dengan kandungan oksigen lebih tinggi sehingga dapat menghasilkan emisi lebih baik dibanding bahan bakar murni saat pembakaran. Dalam penelitian ini, penulis menggunakan bioetanol fuel grade dengan perbandingan E5, E10 dan E15 dengan zat aditif Oxygenate Cyclohexanol yang nantinya hasil torsi akan dibandingkan dengan bahan bakar murni E0. Pengujian dilakukan menggunakan Engine Dynamometer Test. Dari penelitian ini disimpulkan: Pambahan Bioetanol dapat meningkatkan torsi; semakin banyak persentase bioetanol yang dicampurkan maka akan semakin tinggi nilai torsinya. Namun, penambahan aditif membuat rasio udara dan bahan bakar menjadi lean dikarenakan oksigen yang sangat banyak dan menyebabkan nilai torsi menurun.

---

ABSTRACTFossil fuel has become one of modern human primary needs, mainly for motorized vehicles. Nonetheless, due to its drawback, people have created its alternatives, including bioethanol. Bioethanol has higher octane number which produces better emission compared to fossil fuel. However, bioethanol usage is still limited to just mixing it with fossil fuel in a certain ratio. Bioethanol used for this method is fuel grade bioethanol with water percentage less than 0.1 which can improve engine performance as well as produce better emission. Another solution that can reduce emission and lessen Coefficient of Variation COV is by adding Oxygenate additive which has higher oxygen level that helps reducing emission during ignition. In this experiment, writer used fuel grade bioethanol with E5, E10, and E15 ratio with Oxygenate Cyclohexanol additive. Afterwards, torques generated from the experiments will be compared to ones from pure fossil fuel E0 usage. The experiment is conducted by using Engine Dynamometer Test. From the results obtained, it can be concluded that adding bioethanol will increase torque The more bioethanol being added, the higher torque will be generated. However, additive addition makes the ratio between air and fuel become lean and reduce torque due to high level of oxygen. "

"ABSTRACTPermasalahan tentang polusi udara dan kebutuhan energi merupakan fenomena yang dihadapi oleh banyak negara, termasuk di dalamnya Indonesia. Pertumbuhan kendaraan bermotor di Indonesia tahun 2012-2016 mencapai 8,19. Kendaraan roda dua mendominasi kepemilikan kendaraan bermotor di Indonesia sebesar 81,33 dari total pada tahun 2016. Karena permasalahan kebutuhan energi dan polusi udara maka dibutuhkan sumber energi lain berupa bioethanol. Tujuan penelitian ini adalah melakukan analisa terhadap dampak penggunaan fuel grade bioethanol dan zat aditif Oxygenate Cyclohexanol sebagai campuran bahan bakar pada Brake Power yang dihasilkan oleh mesin injeksi 125cc. Penelitian menggunakan engine dynamometer, dengan metode pengambilan data dari putaran mesin 3000-8500 RPM. Campuran bahan bakar yang digunakan adalah E0, E5, E10, dan E15 beserta tambahan aditif ke dalam campuran gasoline dan fuel grade bioethanol. Dari studi didapatkan hasil campuran bahan bakar paling optimum adalah E15 yang dapat meningkatkan rata-rata daya 1,49 atau 0,08 kW dari E0. Maksimum Brake Power yang dihasilkan ada pada campuran E15 dan minimum Brake Power pada E15 dengan tambahan zat aditif Oxygenate Cyclohexanol.

---

ABSTRACTThe problem of air polution and energy demand is faced by many countries, including Indonesia. The growth of motor vehicles in Indonesia in 2012 2016 reached 8.19. Motorcycle dominates motor vehicle ownership in Indonesia by 81,33 of total in 2016. Due to problem of energy demand and air polution other energy resources are needed in the form of bioethanol. The purpose of this research is to analyze the effect of Oxygenate Cyclohexanol as an additive substance to the 125cc engines brake power using a mixture of gasoline and fuel grade bioethanol as the fuel. This research using engine dynamometer, with data retrieval method from engine rotation 3000 8500 RPM. The fuel mixtures that used are E0, E5, E10, and E15 along with additional additive to the gasoline and fuel grade bioethanol mixture. From the study, the most optimum fuel mixture is E15 which can increase brake power average of 1.49 or 0.08 kW from E0. Maximum brake power that engine generates is from E15 mixture and minumum from E15 with additional Oxygenate Cyclohexanol additive substance."

"Bio-oil hasil produksi dari co-pyrolysis CPO-PP tidak dapat langsung digunakan sebagai bahan bakar untuk mesin karena masih mengandung oksigenat yang cukup banyak, korosif, dan tidak stabil. Pada penelitian ini, katalis ZrO2/α-Al2O3-TiO2 diharapkan dapat memperbaiki karakteristik bio-oil dan menciptakan bahan bakar yang memiliki karakteristik mendekati bahan bakar komersial. Katalis disintesis dengan suhu variasi suhu kalsinasi 1150oC dan laju pemanasan 7oC/menit. Pada proses catalytic co-pyrolysis dilakukan variasi komposisi polipropilena pada umpan yang digunakan (0%PP, 50%PP, dan 90%PP) dengan memasukkan katalis sebanyak 15% dari total umpan. Penelitian ini dilakukan menggunakan reaktor tangki berpengaduk dengan jumlah umpan 200 gram, kecepatan pemanasan 10oC/menit, suhu pirolisis 550oC, kecepatan pengadukan 80 rpm, dan laju alir gas nitrogen 100 ml/menit. Produk bio-oil terbaik dihasilkan pada variasi 50%PP dengan yield bio-oil sebesar 50%. Penggunaan katalis ZrO2/α-Al2O3-TiO2 dapat meningkatkan produksi alkana dan alkena dengan menurunkan kandungan asam karboksilat dan keton di dalam biofuel. Hal ini menunjukkan bahwa penggunaan katalis mampu memaksimalkan reaksi deoksigenasi, Berdasarkan analisis GC-MS, H-NMR, dan C-NMR senyawa yang paling dominan adalah alkana dan alkena.......Bio-oil produced from co-pyrolysis CPO-PP cannot be used directly as fuel for engines because it still contains a lot of oxygenate, is corrosive, and unstable. In this study, the ZrO2 / α-Al2O3-TiO2 catalyst is expected to improve the characteristics of bio-oil and create a fuel that has characteristics close to commercial fuels. The catalyst was synthesized with calcination temperature variations of 1150oC and heating rates of 7oC/minute. In the catalytic co-pyrolysis process, variations in the composition of polypropylene in the feed is used (0% PP, 50% PP, and 90% PP) and were carried out by adding a catalyst as much as 15% of the total feed. This research was conducted using a stirred tank reactor with a feed amount of 200 grams, heating rate 10oC/minute, pyrolysis temperature 550oC, stirring speed 80 rpm, and nitrogen gas flow rate of 100 ml/minute. The best bio-oil products are produced in variations of 50% PP with a bio-oil yield of 50%. The use of ZrO2/α-Al2O3-TiO2 catalysts can increase the production of alkanes and alkenes by reducing the carboxylic acid and ketone content in biofuels. This shows that the use of a catalyst is able to maximize the deoxygenation reaction. Based on the GC-MS, H-NMR, and C-NMR analysis the most dominant compounds are alkanes and alkenes."

"Bioethanol is a renewable and oxygenated bio-based resource with the potential to reduce particulate emissions in direct fuel injection diesel engines. This study aims to further diminish the outflow of a Diesel Fuel Engine motor fueled by diesel-bioethanol by identifying the most suitable blend by applying various blends of diesel-bioethanol, namely E10, E20, E50, and E80 blends. The Diesel engine had been tested using solely diesel fuel and then with bioethanol blends for comparison purposes. The results show that bioethanol fuel can provide a lower torque for the Diesel engine, but a similar engine performance occurs in terms of Horse Power. However, the presence of bioethanol inside the blended fuels increases the emissions of Unburned Hydrocarbon, (HC), CO, CO2, and NOx compared to engines that use only Pure Diesel. E10 has been found as the most ideal blend from all the fuels tested. Further research is required to distinguish the E80 fuel blend, as it is unable to be tested on a 6-cylinder engine, since the standard running Diesel engine suitable for the E80 blend fuel is a single cylinder."

"The application of bio-oil for biofuel has been limited due to its low heating value, high acidity and high oxygenate content. pursuant to the urgency of obtaining access to sustainable energy from renewable resources, the studies for bio-oil upgrading have been recently placed in high priority. this study is aimed at identifying the effect of biomass types on bio-oil product characteristics. the conversion of several types of biomass, i.e. rice straw, rubberwood (hevea brasiliensis), and palm empty fruit bunches (efb) to bio-oil by-products was investigated in a catalytic fast pyrolysis (cfp) reactor using a ni/zsm-5 nickel nitrate and zeolite catalyst at 550oc and at atmospheric pressure. the results show that ni/zsm-5 catalyst has actively enhanced the de-oxygenation reaction process and aromatic production. the composition of aromatic compounds in bio-oil from rubberwood, rice straw, and efb are 10.25 wt%, 7.8 wt%, and 5.98 wt%, respectively. in the absence of a catalyst, bio-oil from rice straw contains no aromatics."