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All Journal International Journal of Renewable Energy Development Jurnal Keteknikan Pertanian Jurnal Pengelolaan Sumberdaya Alam dan Lingkungan (Journal of Natural Resources and Environmental Management) agriTECH Agrokreatif Jurnal Ilmiah Pengabdian kepada Masyarakat Warta IHP (Warta Industri Hasil Pertanian) Jurnal Ilmiah Rekayasa Pertanian dan Biosistem Jurnal Teknik Pertanian Lampung (Journal of Agricultural Engineering) Jurnal Teknik Mesin Indonesia International Journal of Renewable Energy Development
Nelwan, Leopold Oscar
Departemen Teknik Mesin Dan Biosistem, Fakultas Teknologi Pertanian, Institut Pertanian Bogor, Kampus IPB Dramaga, Bogor, 16680
Aerospace Engineering Agriculture, Biological Sciences & Forestry Automotive Engineering Chemistry Control & Systems Engineering Earth & Planetary Sciences Electrical & Electronics Engineering Energy Engineering Environmental Science Industrial & Manufacturing Engineering Mechanical Engineering

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Pemodelan Matematik Kinerja Pengering Surya Efek Rumah Kaca (ERK)-Hibrid Menggunakan Rak Berputar secara Vertikal Sigit Triwahyudi; Bandul Suratmo; Budi Rahardjo; Leopold Oscar Nelwan
agriTECH Vol 36, No 3 (2016)
Publisher : Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (997.581 KB) | DOI: 10.22146/agritech.16608

Abstract

This paper presents a performance test and mathematical modeling of greenhouse effect (GHE)-Hybrid solar dryer with vertical rotating rack. The dryer consists of a greenhouse dryer (1100 × 860 × 1300) mm with eight rack and additional heating system consists of a flat plate collector (1,04 m2), a hot water storage tank (197 liters) and a heat exchanger. To investigate the performance of solar greenhouse dryer, five experimental variation speed of rack were conducted (1, 4, 7, 10 rpm) and without rotation. Materials used in the experiment are local cardamom (Amomum cardamomum Wild). Weight of each experiment  about  9 to 10 kg. The average temperature of the hot water storage tank varies from 50.0 to 55.0 °C, drying air  temperature between 38.9 to 45.9 °C, while the relative humidity (RH) of drying chamber ranged from 32.1 to 47.4 %. Variation of rotational speed affects on the uniformity of product temperature and water content in each rack drying. At rotation 1 rpm  (experiment II), obtained  as the best conditions (temperature and moisture content are most uniform). Increasing rotational speed of rack causes increasing in standard deviation of  product temperature and moisture content. To simulate the performance of the dryer, mathematical modeling based on heat  and mass transfer and a thin layer drying  approaches were conducted. Equations solved numerically using the finite difference Euler with Visual Basic Application (VBA) program on Excel. Validation was conducted by comparing the calculation results of mathematical modeling (data prediction) with measurement data (data observation). Criterion validity was determined by  the value of the coefficient of determination (R2), the value of RMSD and MAPD. Mathematical models that have been developed can be described precisely the temperature of the hot water storage tank, temperature of the drying chamber, temperature of the product as well as a moisture content decrease. ABSTRAKMakalah ini menyajikan uji unjuk kerja dan pemodelan matematik pengering energi surya (ERK)-Hibrid  menggunakan  rak berputar secara vertikal. Pengering terdiri dari bangunan rumah kaca berukuran (1100 × 860 × 1300) mm dengan delapan buah rak dan sistim pemanas tambahan yang terdiri dari kolektor plat datar (1,04 m2), tangki penyimpan air panas (197 liter) dan penukar panas. Untuk mengetahuikinerja pengering energi surya, dilakukan lima kali percobaan variasi kecepatan putar rak (1, 4, 7, 10 ) rpm dan tanpa pemutaran rak. Bahan yang dipergunakan pada pengujian adalah kapulaga lokal (Amomum cardamomum Wild). Masing-masing percobaan seberat 9 sampai dengan 10 kg. Rata-rata suhu air tangki penyimpan panas bervariasi dari 50,0 sampai dengan 55,0 °C suhu ruang pengering antara 38,9 sampai dengan 45,9 °C, sedangkan kelembaban relatif (RH) ruang pengering berkisar antara 32,1 sampai dengan 47,4 %. Perlakuan pemutaran rak berpengaruh terhadap keseragaman suhu bahan maupun kadar air pada masing rak pengering. Pada perlakuan pemutaran 1 rpm (percobaan II), didapatkan kondisi terbaik (suhu bahan maupun kadar air yang paling seragam). Dengan kecepatan putar rak yang semakin meningkat menyebabkan nilai ragam suhu bahan maupun kadar air semakin meningkat. Untuk melakukan simulasi unjuk kerja dilakukan pemodelan matematik berdasarkan pindah panas dan massa serta pendekatan pengeringan lapisan tipis. Persamaan diselesaikan secara numerik menggunakan finite difference Euler dengan bantuan bahasa pemrograman Visual Basic Aplication (VBA) Excell. Validasi dilakukan dengan membandingkan antara perhitungan hasil pemodelan (data prediksi) dengan data hasil pengukuran (data observasi). Kriteria kevalidan ditentukan dengan melihat nilai koefisien determinasi (R2), nilai RMSD maupun nilai MAPD. Pemodelan  matematik yang telah dibangun dapat menggambarkan dengan tepat perubahan suhu air tangki penyimpan panas, suhu ruang pengering, suhu bahan maupun penurunan kadar air.
Edukasi Jelantah sebagai Sumber Energi pada Kelompok Ibu Rumah Tangga di Desa Petir, Bogor Dyah Wulandani; Leopold Oscar Nelwan; Dwi Setyaningsih
Agrokreatif: Jurnal Ilmiah Pengabdian kepada Masyarakat Vol. 7 No. 3 (2021): Agrokreatif Jurnal Ilmiah Pengabdian kepada Masyarakat
Publisher : Institut Pertanian Bogor

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29244/agrokreatif.7.3.193-200

Abstract

Jelantah is the used cooking oil. After being used more than three times for frying, the oil will be oxidized by ambient air, and dangerous free radical compounds are formed. Consuming of jelantah in certain amounts, can trigger diseases such as blockage of blood vessels, cancer and nervous disorders. In addition, jelantah discharged into the drains will cause blockage of drains and kill water ecosystems. However, jelantah can be used as an energy source and other products that have economic value. The purpose of this activity is to provide education for groups of housewives in Babakan Gang Salak, Petir Village, Bogor Regency regarding the dangers and benefits of jelantah, introducing simple technology of biodiesel production. The methods used include questionnaires, training and monitoring. The 1st, 2nd and 3rd trainings were held with different participants in the same location. The the participants’ enthusiasm and local site leaders was very high and they wished training for a wider range of participants. The training has been conducted successfully, which was showed that most of the participants could increase their skills and knowledge about the dangers and benefits of jelantah is biodiesel production. This knowledge is supposed to be applied in everyday life by not consuming jelantah for frying food, but it is used as a raw material for biodiesel production.
Pemodelan Dan Simulasi Pengeringan Jagung Pipilan Dalam Pengering Rotari Tumpukan Leopold Oscar Nelwan; I Nengah Suastawa; Sulikah .
Jurnal Keteknikan Pertanian Vol. 22 No. 2 (2008): Jurnal Keteknikan Pertanian
Publisher : PERTETA

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19028/jtep.022.2.%p

Abstract

A mathematical model of shelled corn drying has been developed in order to simulate the distribution of drying air temperature and humidity as well as the grain moisture content in a rotary bed dryer. The model was based on heat and mass balance of cylindrical packed bed of grain with airflow passing through the bed. Whenever the air relative humidity is higher than the equilibrium moisture content, it is assumed the condensation process will be occurred. Finite difference method with Euler scheme was used to perform the computation. The result showed that the model developed can predict the distribution ofgrain temperature and moisture content. The simulation conducted showed that there would be a wide variation ofmoisture content and temperature if mixing was not applied during the drying process. Mixing was significantly reduced the moisture content variation until a maximum of 0.8% w.b.Keywords: rotary bed drying, mathematical model, simulation, corn dryingDiterima: 5 Februari 2008; Disetujui: 26 Juni 2008
Disain dan Uji Kinerja Pengering Rotari Tumpukan untuk Pengeringan Jagung Pipilan Sulikah .; Leopold Oscar Nelwan; I Nengah Suastawa
Jurnal Keteknikan Pertanian Vol. 22 No. 2 (2008): Jurnal Keteknikan Pertanian
Publisher : PERTETA

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19028/jtep.022.2.%p

Abstract

A rotary bed dryer for grain had been developed and tested in this study. The dryer was designed in order to provide an effective mixing effect. The dryer used perforated cylindrical drum for its chamber and was rotated by an electrical motor. The result showed that when the numbers of rotation was 20, the shelled corn had been mixed effectively. To meet this condition, the drum was rotated for 5 minutes every 15 minutes during the drying process. As the result, the variation of moisture Qontent in radial direction was less than 1.1% w.b. With drying air temperature of 670C and 600C the specific energy consumption of the dryer were 5.6 MJ/kg to reduce the moisture content from 25 to 16% b.b. and 5.4 MJ/kg from 17 to 13% w.b. Thermal energy was the highest contributor of total energy consumption. As it had been expected, the full load of the dryer provided a lower mechanical energy requirement than the half load. Keywords: rotary bed dryer, mixing, specific energy consumption Diterima: 5 Februari 2008; Disetujui: 10 Juni 2008
Analisis Sistem Heat Pump Kompresi Uap untuk Pengeringan Gabah Damawidjaya Biksono; Leopold Oscar Nelwan; Tineke Mandang; Dyah Wulandani; Yogi Sirodz Gaos
Jurnal Keteknikan Pertanian Vol. 4 No. 2 (2016): JURNAL KETEKNIKAN PERTANIAN
Publisher : PERTETA

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2026.833 KB) | DOI: 10.19028/jtep.04.2.%p

Abstract

AbstractAs a drying system, heat pump drying with appropriate configuration is potential to safe energy. The objective of this research was to develop vapor compression heat pump system for rough rice drying and to obtain low energy consumption from several system configurations. Therefore, the model of vapor compression heat pump system was designed in which its configuration was modifiable. The result showed that the ratio of specific moisture extraction rate which calculated mechanic and thermal consumption (SMERTot) upon resistive heating dryer for those several configurations was 159 – 329%. The open cycle heat pump drying method with intermittent operation produced the highest specific moisture extraction rate which only calculated thermal energy (SMERT) and SMERTot at 7.06 and 5.06 kg/kWh, respectively. Intermittent operation did not much influence drying rate but significantly reduced energy consumption. Ambient air inlet which placed before evaporator and condenser on a closed cycle could produce different SMERTot i.e. 4.01 dan 3.07 kg/kWh respectively. The utilization of ambient air through forced convection in heat exchanger could increase SMERTot, while the utilization of air flow the dryer from outlet could reduce SMERTot.AbstrakPengeringan heat pump merupakan sistem pengeringan yang berpotensi menghemat energi terutama apabila konfigurasinya sesuai. Tujuan dari penelitian ini adalah mengembangkan sistem heat pump kompresi uap (HPKU) untuk pengeringan gabah dan mendapatkan konsumsi energi yang rendah dariberbagai konfigurasi sistem. Untuk itu pada penelitian ini didesain sebuah model sistem pengering heat pump yang konfigurasinya dapat diubah-ubah untuk  pengeringan gabah. Hasil percobaan memperlihatkan bahwa rasio peningkatan specific moisture extraction rate yang memperhitungkan konsumsi energi mekanik dan termal (SMERTot) terhadap pengering pemanas resistif untuk berbagai konfigurasi tersebutadalah 159 – 329%. Metode pengeringan heat pump siklus terbuka dengan pengoperasian HPKU yang intermittent memberikan specific moisture extraction rate yang hanya memperhitungkan konsumsi energi termal (SMERT) dan SMERTot yang paling tinggi yaitu masing-masing 7.06 dan 5.06 kg/kWh. Pengoperasian intermittent tidak banyak mempengaruhi laju pengeringan, tetapi secara nyata menurunkan konsumsi energi. Penempatan inlet udara lingkungan sebelum evaporator dan sebelum kondensor pada siklus tertutup memberikan SMERTot yang berbeda yaitu 4.01 dan 3.07 kg/kWh. Penggunaan udara lingkungan dengan menggunakan konveksi paksa melalui penukar panas dapat meningkatkan SMERTot, sedangkan penggunaan aliran udara dari keluaran pengering dapat menurunkan nilai SMERTot.
Simulasi Pengeringan Gabah pada Pengering Spouted Bed Dua Dimensi Yusnita Oni Napitu; Leopold Oscar Nelwan; Dyah Wulandani
Jurnal Keteknikan Pertanian Vol. 4 No. 2 (2016): JURNAL KETEKNIKAN PERTANIAN
Publisher : PERTETA

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2409.099 KB) | DOI: 10.19028/jtep.04.2.%p

Abstract

AbstractA mathematical model developed by Nellist et al. (1987) was adopted in this continuous two dimensional spouted bed dryer (2DSB) configuration. The objective of this research was to predict air temperature, grain temperature, absolute humidity and moisture content during the drying process in 2DSB. In simulation, spouted bed was divided into two regions which were spout and downcomer regions. Air and grains in spout and downcomer were assumed to be moving with co- and counterflow principles. During experiments, drying air temperature at 80oC and different paddy initial moisture contents (at 41% db, 36% db and 30% db) were used. Based on data, the air temperature profiles in spout region showed that air temperature dropped significantly with the axial positions while downcomer regions resulted fluctuated value. The average deviation of the air temperature in the spout was less than 4.5% and within downcomer was less than 4.2%. Grain temperature and absolute humidity in spout region increased slowly whilst decreasing in steps in downcomer regions with axial position. The moisture content decreased both in spouted and downcomer regions. Moisture reduction in spout region was higher than downcomer regions because of the high air flow rate in spout region.AbstrakPenelitian ini menggunakan model matematika yang dikembangkan oleh Nellist et al. (1987) untuk pengering spouted bed dua dimensi tipe kontinyu. Tujuan dari penelitian ini adalah menduga sebaran suhu udara, suhu gabah, kelembaban mutlak udara dan kadar air selama proses pengeringan. Pada proses simulasi, ruang pengering dibagi menjadi dua daerah yaitu daerah spout dan daerah downcomer. Udara dan bahan di daerah spout dan downcomer diasumsikan bergerak dengan prinsip aliran co- dan counterflow. Suhu udara yang digunakan selama pengujian adalah suhu 80oC dengan kadar air awal bahan yang berbeda-beda yaitu 41% bk, 36% bk dan 30% bk. Dari data pengujian menunjukkan bahwa suhu udara di daerah spout akan menurun secara signifikan terhadap posisi aksial ruang pengering tetapi pada daerah downcomer suhu udara bernilai fluktuatif. Nilai rataan deviasi pada pendugaan suhu udara daerah spout bernilai kurang dari 4.5% dan pada daerah downcomer deviasi bernilai kurang dari 4.2%. Suhu gabah dan kelembaban mutlak udara pada daerah spout menunjukkan bahwa nilai akan naik secara bertahap sementara untuk daerah downcomer nilai menurun secara bertahap terhadap posisi aksial. Penurunan kadar air menunjukkan bahwa untuk daerah spout dan daerah downcomer mengalami penurunan nilai. Penurunan kadar air daerah spout lebih besar dibandingkan daerah downcomer karena pada daerah spout laju aliran udara lebih besar.
Uji Performansi Alat Pengering Efek Rumah Kaca Hybrid Tipe Rak Berputar untuk Bawang Merah (Allium Cepa L.) Dyah Wulandani; Leopold Oscar Nelwan; Sri Endah Agustina
Jurnal Keteknikan Pertanian Vol. 5 No. 2 (2017): JURNAL KETEKNIKAN PERTANIAN
Publisher : PERTETA

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1626.141 KB) | DOI: 10.19028/jtep.05.2.%p

Abstract

Abstract Drying is the most important step of shallot processing before it is consumed. Generally, the farmer dried shallot by spreading it on the ground under the sun, however sun drying could not be implemented at rainy season, therefore the mechanical dryer is necessary. The research introduced the rotary tray hybrid green house effect (GHE) solar dryer for shallot drying. The objective of the study was to test the performance of the rotary rack of the GHE hybrid solar dryer for shallot drying. Three drying experiments has been done to got the performance of the Rotary rack type-hybrid GHE solar dryer. The dryer has drying efficiency of 20.8 % and the energy consumed of 12.1 MJ/kg vapor evaporated. Base on the cost analysis, it was obtained that the drying cost was Rp 1,013,- per kg fresh shallot. The shallot drying bussiness is feasible with payback period of 4 years. Volatile reducing substances (VRS) of dried shallot was 31.1 μg eq/g which has no significant decrease compared with fresh shallot. GHE solar dryer -hybrid of solar and biomass energy- utilization for shallot drying is still useful when the solar irradiation is unavailable for sun drying. It could reduce losses caused of decay of shallot.Abstrak Pengeringan merupakan tahap proses pengolahan bawang sebelum siap dikonsumsi. Secara umum petani menjemur bawang merah di bawah sinar matahari. Pada saat musim penghujan, penjemuran langsung tidak mungkin dilakukan, oleh karena itu dibutuhkan pengering mekanis. Pengering Efek Rumah Kaca (ERK) energi hibrid biomassa-surya tipe rak berputar merupakan salah satu pilihan. Untuk itu tujuan penelitian ini adalah untuk menguji performansi pengering ERK hibrid untuk mengeringkan bawang merah (Allium Cepa L.). Tiga buah percobaan pengeringan telah dilakukan untuk mendapatkan performansi pengering ERK hibrid tipe rak berputar. Pengering ERK hibrid tipe rak berputar memiliki tingkat efisiensi pengeringan 20.8 % dan nilai konsumsi energy pengeringan yang rendah yaitu 12.1 MJ/kg uap. Berdasarkan analisis biaya, diperoleh biaya pokok pengeringan sebesar Rp 1,013,- per kg bawang merah segar. Usaha pengeringan bawang merah akan kembali modal pada tahun ke-4. Volatile reducing substances (VRS) bawang merah kering adalah 31.1 μg ek/g, penurunannya sangat kecil dibandingkan dengan nilai VRS bawang segar. Pada kondisi dimana surya tidak tersedia untuk melakukan metode pengeringan dengan penjemuran, maka penggunaan pengering ERK hibrid berenergi surya dan biomassa dapat menekan kerugian yang diakibatkan oleh kebusukan.
Kajian Pengeringan dan Pendugaan Umur Simpan Seledri pada Berbagai Bahan Kemasan Fleksibel Tri Yulni; Rokhani Hasbullah; Leopold Oscar Nelwan
Jurnal Keteknikan Pertanian Vol. 5 No. 2 (2017): JURNAL KETEKNIKAN PERTANIAN
Publisher : PERTETA

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1091.015 KB) | DOI: 10.19028/jtep.05.2.%p

Abstract

AbstractCelery is a perishable horticultural product due to its high water content. This condition leads to a short durability of the celery, thus efforts to prolong its shelf life are required. This study aimed at studying the effects of immersion in sodium metabisulphite and drying temperature on the quality of dried celery leaves, and determining its shelf life using acceleration method based on critical moisture content approach. The results showed that soaking treatment using solution of sodium metabisulphite prior to drying process was able to maintain the dried celery leaves qualities, which resulted in higher chlorophyll content, lower apparent density, higher rehydration ratio, and higher VRS (volatile reducing substance) in comparison without soaking treatment. Moreover chlorophyll content, apparent density, volatile reducing substance (VRS), and rehydration behaviours were affected by the drying temperature. Shelf life of dried celery leaves based on critical moisture content approach represented in linear low density polyethylene (LLDPE) plastic, polypropylene (PP), and aluminium foil oriented polypropylene (OPP) were 30, 51, and 790 days, respectively. AbstrakSeledri merupakan produk hortikultura yang mudah rusak karena memiliki kandungan air yang tinggi. Kondisi ini menyebabkan seledri tidak tahan lama disimpan sehingga diperlukan penanganan untuk memperpanjang umur simpannya. Tujuan penelitian ini adalah mengkaji pengaruh perendaman dalam larutan natrium metabisulfit dan suhu pengeringan terhadap mutu daun seledri kering dan menentukan umur simpan daun seledri kering berdasarkan metode akselerasi dengan pendekatan kadar air kritis. Hasil penelitian menunjukkan perendaman dalam larutan natrium metabisulfit sebelum pengeringan mampu mempertahankan mutu daun seledri kering, dimana dihasilkan kandungan klorofil lebih tinggi, densitas kamba lebih rendah, rasio rehidrasi lebih tinggi, serta kandungan VRS lebih tinggi dibandingkan seledri tanpa perlakuan perendaman. Selain kandungan klorofil, nilai densitas kamba, VRS, dan rasio rehidrasi dipengaruhi oleh suhu pengeringan. Umur simpan seledri berdasarkan metode akselerasi dengan pendekatan kadar air kritis didapat dalam kemasan LLDPE, PP, dan aluminium foil OPP berturut-turut adalah 30, 51, dan 790 hari.
Rancangan Kemasan dan Aplikasi Ice gel untuk Transportasi Jamur Tiram (Pleurotus ostreatus) Mila Siti Amalia; Emmy Darmawati; Leopold Oscar Nelwan
Jurnal Keteknikan Pertanian Vol. 5 No. 2 (2017): JURNAL KETEKNIKAN PERTANIAN
Publisher : PERTETA

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1176.177 KB) | DOI: 10.19028/jtep.05.2.%p

Abstract

AbstractThe high ambient temperatures at the oyster mushrooms distribution will accelerate deterioration. Ice gel can be used to lower the mushrooms temperature during transport, so that the mushrooms quality can be maintained. This research was aimed to design the packages, determine the ice gel need, and decreased the oyster mushroom temperature up to 15 oC by applying ice gel. The research treatments were giving ice gel (G): without an ice gel (G0), the ice gel formation 1 (G1) placed the ice gel vertically between every partition on the mushroom retail package and the ice gel formation 2 (G2) placed two ice gel on the top of the package horizontally and an ice gel at the side of the package vertically; and plastic PP perforation treatment: 0.1 % (P1) and 0.3 % (P2) of package area. The result was the 50 x 40 x 24 cm corrugated cardboard dimension had been designed for 3 kg of mushroom and 2.52 kg ice gel could be used with the expectation to lower the mushrooms temperature up to 15 ° C for 2.5 hours. The ice gel formation 2 with perforated 0.3 % and 0.1 % could decrease mushroom temperature at the top part, up to 11 oC and 12.2 oC. While, the rate of mushroom temperature in the package were 16.9 oC and 17.1oC during 2.5 hours.                                                                                                                           Abstrak Suhu lingkungan yang tinggi saat distribusi jamur tiram akan mempercepat penurunan mutu. Ice gel dapat digunakan untuk menurunkan suhu jamur selama transportasi sehingga kualitas jamur dapat dipertahankan. Penelitian ini bertujuan untuk merancang kemasan, menentukan kebutuhan ice gel dan menurunkan suhu jamur tiram hingga 15 oC saat transportasi dengan aplikasi ice gel. Perlakuan yang diberikan adalah pemberian ice gel (G): tanpa ice gel (G0), ice gel susunan 1 yaitu diletakkan secara vertikal antara masing-masing sekat pada kemasan ritel jamur (G1) dan ice gel susunan 2 yaitu 2 buah ice gel diletakkan secara horizontal dibagian atas kemasan dan 1 buah ice gel secara vertikal pada sisi kemasan (G2). Perlakuan perforasi (P) pada plastik PP: 0.1 % (P1) dan 0.3 % (P2) dari luas kemasan. Hasil penelitian ini adalah kemasan berbahan karton gelombang dengan dimensi 50 cm x 40 cm 24 cm yang telah dirancang untuk wadah 3 kg jamur dan 2.52 kg ice gel dapat digunakan dengan harapan dapat menurunkan suhu jamur hingga 15 oC selama 2.5 jam. Posisi ice gel susunan 2 dengan perforasi plastik 0.3 % dan 0.1 % dapat menurunkan suhu jamur bagian atas masing-masing hingga 11 oC dan 12.2 oC, sedangkan rata-rata suhu jamur dalam kemasan adalah 16.9 dan 17.1 selama 2.5 jam.
Simulasi Tungku Gasifikasi Tipe Natural Draft Berbasis Model Efek Cerobong dan Keseimbangan Termokimia Leopold Oscar Nelwan; Dyah Wulandani; Edy Hartulistiyoso; Sri Endah Agustina; Dziyad Dzulfansyah; Erlanda Augupta Pane
Jurnal Keteknikan Pertanian Vol. 6 No. 1 (2018): JURNAL KETEKNIKAN PERTANIAN
Publisher : PERTETA

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1437.842 KB) | DOI: 10.19028/jtep.06.1.61-68

Abstract

AbstractThis study was aimed to simulate a novel configuration of gasification stove with the natural draft principles (natural draft gasification or called as NDG stove) based on chimney effect and thermochemical equilibrium modeling. The thermochemical equilbrium model used general stoichiometric gasification,methanation and water-gas shift equations and their equilibrium constant equations as well as the general energy balance equation. Those equations were coupled with the chimney effect equation and then solved to obtain the reaction coefficients, equilibrium constants, reaction temperature as well as the mass flow rate of air. Simulation was performed by using VBA programming codes in Excel. Subsequently, a stove was built in order to obtain the charcoal consumption rate data which is required to validate the model. The test results showed that the combustion rate was constant i.e. 8.8 g/min and the quality of the flame of the stove was visually good. The calculation result showed that the model could succesfully predict the product gases including CO, CH4, CO2, O2, N2 and other gases. The simulation showed that by using lower stoveheight (0.5 and 0.4 m) the combustible gases (CO, H2 and CH4) compositions were increased in such a way that with same combustion rate the potential heat of gas increased from 2.33 kW at stove height of 0.6 m to 2.63 kW at 0.4 m.AbstrakPenelitian ini bertujuan untuk mensimulasi tungku gasifikasi dengan konfigurasi baru yang menggunakan prinsip natural draft (tungku natural draft gasification atau disebut sebagai tungku NDG) didasarkan padapemodelan efek cerobong dan keseimbangan termokimia. Model keseimbangan termokimia menerapkan persamaan stoikiometri untuk gasifikasi, methanation dan water-gas shift, persamaan-persamaan konstanta keseimbangannya serta persamaan neraca energi umum. Persamaan-persamaan tersebut digabungkan dengan persamaan efek cerbong dan dipecahkan untuk memperoleh koefisien reaksi, konstanta keseimbangan, suhu reaksi dan laju aliran massa udara. Selanjutnya tungku tersebut dikonstruksi dan diuji untuk memperoleh data laju konsumsi arang yang dibutuhkan untuk validasi model. Hasil pengujiankinerja menunjukkan bahwa penggunaan tungku untuk arang kayu memiliki laju pembakaran yang konstan 8.8 g/menit dan kualitas nyala api tungku ini cukup baik secara visual. Hasil perhitungan menunjukkanbahwa model yang diterapkan telah dapat memprediksi konsentrasi gas-gas produk yang mencakup CO, CH4, CO2, O2 serta gas N2 dan gas-gas lainnya. Hasil simulasi menunjukkan bahwa tinggi tungku yang lebih rendah (0.5 dan 0.4 m) memberikan konsentrasi gas-gas mampu bakar yang lebih tinggi sedemikian hingga dengan laju konsumsi arang yang sama daya gas potensialnya meningkat dari 2.33 kW pada tinggi0.6 m menjadi 2.63 kW pada tinggi 0.4 m.
Co-Authors Achmad Fitrah Maulidin Ali Usman, Ali Bandul Suratmo Budi Rahardjo Chandra Gupta Damawidjaya Biksono Devi Tanggasari Dwi Setyaningsih Dyah Wulandani Dziyad Dzulfansyah Edy Hartulistiyoso Eko Heri Purwanto Emmy Darmawati Erlanda Augupta Pane Hayatri Sali Setia Herry Suhardiyanto I Nengah Suastawa I Wayan Astika I Wayan Budiastra Irwansyah Irwansyah Kudang Boro Seminar M Ridwan Dwi Astanto Mila Siti Amalia Mohamad Solahudin Mohammad Aftaf Muhajir Muhamad Yulianto Muhamad Yulianto Nurul Choerunnisa Omil Charmyn Chatib Putri Ayu Ira Distriani Ranti - Ranti Rokhani Hasbullah Rustam Efendi Samsudin Samsudin Sigit Triwahyudi Siregar, Gokma Ampetua Sofyan Sjaf Sri Endah Agustina Sulikah . Sutrisno . Syahputra, Sufri Yanto Tamaria Panggabean Tineke Mandang Tri Yulni Tya Lestari Usman Ahmad Wawan Hermawan Winny Purnama Sari Y. Aris Purwanto Yogi Sirodz Gaos Yusnita Oni Napitu