Study on Energy Consumption For Soybean-Sauce Production 'Pabrik Kecap Zebra' Ciampea, Bogor

Energy is an Important factor for the success of industrialitation. and energy consumption of an industry. especially the small and medium industry. should be optimized based on the energy efficiency system. The objective of this research is to analyse the energy consumption for soybean sauce production at 'Pabrik Kecap Zebra'. Ciampea Bogor. and to evaluate the efficiency of stoves used at the industry

PENGARUH PENYUSUTAN TERHADAP KARAKTERISTIK PENGERINGAN TEMU PUTIH

The effects of drying conditions on shrinkage of zedoary were studied. A thin-layer dryer with machine vision 2D system and image analysis software was used. Zedoary slices were dried at temperatures of 50, 60 and 70oC (at constant RH) and relative humidities of 20%, 30% and 40% (at constant temperature). The falling drying rate data were used to calculate the effective diffusion coefficients from the Fick’s equation. Changes in area of the slice were measured every 5 minute during drying. Shrinkage showed almost linear relation with moisture content. It was found that air temperature and relative humidity had no significant effect on shrinkage. Drying took place entirely in the falling rate period. Slices dried at 70oC showed more bend than slices dried at 50 and 60oC. Effective diffusivity values by considering the shrinkage were estimated in the range of 4.74-6.19×10-9 m2/s for studied drying temperatures.Keywords: drying, shrinkage, moisture, diffusivity, image analysis, zedoar

Analisis Eksergi Pengeringan Irisan Temulawak

Temulawak (Curcuma xanthorrhiza Roxb.) merupakan tanaman obat yang simplisianya digunakan sebagai bahan baku pembuatan jamu atau obat tradisional. Pengeringan merupakan proses utama dalam memproduksi simplisia. Untuk menganalisis efisiensi energi suatu proses pengeringan umumnya digunakan hukum termodinamika pertama yang menjelaskan tentang prinsip kekekalan energi. Akan tetapi teori ini mempunyai keterbatasan dalam mengukur penurunan kualitas energi. Untuk mengetahui apakah energi yang digunakan pada proses pengeringan sudah digunakan secara optimal dari sisi kualitas, digunakan hukum termodinamika kedua atau yang dikenal dengan analisis eksergi. Tujuan penelitian ini adalah menentukan efisiensi proses pengeringan lapisan tipis irisan temulawak dengan metode analisis energi dan eksergi. Dalam studi ini, metode analisis energi dan eksergi berdasarkan hukum termodinamika pertama dan kedua telah digunakan untuk menghitung rasio penggunaan energi dan besaran eksergi yang musnah (exergy loss). sehingga efisiensi proses pengeringan irisan temulawak dapat ditentukan secara akurat. Hasil penelitian menunjukkan bahwa kondisi proses pengeringan mempengaruhi rasio penggunaan energi dan efisiensi eksergi pengeringan. Semakin tinggi suhu dan RH pengeringan maka rasio penggunaan energi semakin rendah dan efisiensi eksergi semakin tinggi. Efisiensi eksergi pengeringan temulawak bervariasi antara 96,5%-100% untuk selang suhu 50 oC hingga 70 oC pada RH 40% serta 82,3% - 100% untuk selang RH 20% hingga 40% pada suhu 50 oC

Freeze drying of food materials is a time and energy consuming process, hence a high cost process. The drying rate is limited by heat and mass transfer process within the dried portion of the product. In order to improve the freeze drying performance, it is important to know parameters which affect the drying characteristics of each spesific food material, in regard to the drying time and the energy consumption. The objective of this experiment was to study the freeze drying characteristic of miched beef especially the effect of freezing rate and surface temperature of the material to the drying time. The study was conducted with freezing rate at 7.71 cmhours and 1.94 cmhours which are classified into fast and slow freezing rate, while the surface temperature of the material was controlled at 40 OC, 35 OC, and 30 OC. The experimental results confirmed that the faster freezing rate then the longest drying time, while the higher surface temperature give a shorter drying time of miched beef. It is important to determine the optimal freezing rate and surface temperature from the view point of energy consumption.

Freeze drying of food materials is a time and energy consuming process, hence a high cost process. The drying rate is limited by heat and mass transfer process within the dried portion of the product. In order to improve the freeze drying performance, it is important to know parameters which affect the drying characteristics of each spesific food material, in regard to the drying time and the energy consumption. The objective of this experiment was to study the freeze drying characteristic of miched beef especially the effect of freezing rate and surface temperature of the material to the drying time. The study was conducted with freezing rate at 7.71 cmhours and 1.94 cmhours which are classified into fast and slow freezing rate, while the surface temperature of the material was controlled at 40 OC, 35 OC, and 30 OC. The experimental results confirmed that the faster freezing rate then the longest drying time, while the higher surface temperature give a shorter drying time of miched beef. It is important to determine the optimal freezing rate and surface temperature from the view point of energy consumption

ANALISIS EKSERGI PADA TEKNOLOGI PRODUKSI BIODIESEL KELAPA SAWIT

ABSTRAKBiodiesel merupakan bahan bakar alternatif yang dapat menggantikan bahan bakar diesel, karena sifatnya yang terbarukan dan ramah lingkungan. Biodiesel dapat diproduksi baik secara proses katalitik ataupun non-katalitik. Makalah ini membahas dua teknologi yang berbeda dalam memproduksi biodiesel kelapa sawit, yaitu proses katalitik yang menggunakan katalis basa dan proses non katalitik uap metanol superheated (superheated methanol vapor / SMV). Analisis eksergi dilakukan untuk membandingkan kedua teknologi tersebut. Sistem tertutup diasumsikan pada analisis eksergi, sedangkan eksergi kinetik dan potensial diabaikan. Hasil penelitian menunjukkan bahwa total efisiensi eksergi untuk proses non-katalitik SMV lebih rendah dibandingkan proses katalitik, yaitu sebesar 92,61% dan 95,37%, secara berurutan. Proses penguapan metanol memberikan kontribusi yang tinggi pada ireversibilitas (tidak mampu balik), yaitu sebesar 2802.07 kJ/kg biodiesel. Penerapan proses resirkulasi panas dapat meningkatkan efisiensi eksergi pada proses produksi biodiesel, terutama apabila metode SMV akan diterapkan. Ireversibilitas pada proses non-katalitik SMV lebih tinggi dibandingkan proses katalitik, karena kebutuhan suhu yang tinggi pada proses non-katalitik SMV. Oleh karena itu, perbaikan proses SMV sangat perlu dilakukan, terutama pada proses penguapan metanol, guna meningkatnya efisiensi proses tersebut.Kata kunci: minyak sawit, biodiesel, uap metanol superheated, katalis basa, analisis ekserg

Experimental and Theoritical Analysis of Thermal Properties in Zephyr Bamboo Tali (Gigantochloa Apus Kurz)

Specific heat, thermal conductivity and thermal diffusivity of Bamboo panel are USAble to support the Programming of Design and Planning in the Structure of the Agricultural Building Construction. The Specific heat of Bamboo's fiber, sheet and panel using the method of mixtures varied from 1.585-2.789 J/gr oC, with a mean value of 2.227 J/gr oC in the temperature difference range of 9 ± 0.1oC . It was found it will increase linearly with an increase in the sample temperature. Thermal conductivity values of Bamboo's fiber based on the transient line heat source technique varied from 0.1035 x 10-3-0.1322 x10-3 J/ cm2 sec oC in the sample temperature 22 to 30 oC on thermal diffusivity of bamboo fiber in 22-30 oC was found to be 0.0823 x 10-3J/cm secoC. The sorption Isotherm and the water activity in the bamboo's panel is depend on the chemical composition, glue laminated, additive and the porosity. There are related with the absorbing of the water into the bounded water and the diffusivity of the water in and out the panel. The moisture equilibrium range are 7.89 to 19.22 percent in the control of the circumstances and 11 to 75 % of the environment.relative humidity

Kajian Eksergi pada Mesin Pendingin Adsorpsi Menggunakan Pasangan Silikagel-Metanol

Sistem pendingin adsorpsi merupakan salah satu dari sistem pendingin yang ramah lingkungan, dimana dalam ope-rasinya sistem ini dapat dibangkitkan menggunakan sumber energi terbarukan seperti biomassa ataupun sinar surya. Sistem pendingin adsorpsi yang digunakan dalam percobaan ini menggunakan pasangan silika gel-metanol sebagai absorben dan refrigeran. Tujuan dari penelitian ini adalah mendapatkan kinerja mesin pendingin adsorpsi intermit- ten pasangan silikagel-metanol dan melakukan analisis eksergi pada mesin pendingin adsorpsi intermitten pasangan silikagel­metanol. Metode penelitian diawali dengan pengujian terhadap kebocoran pada semua komponen di da- lam sistem pendingin adsorpsi dan dilanjutkan dengan pengujian sistem pendingin adsorpsi menggunakan pasangan silikagel­metanol. Suhu tiap komponen yaitu generator, kondensor, evaporator dan pipa­pipa masukan dan keluaran diukur dengan menggunakan termokopel tipe C­C yang dihubungan dengan alat perekam suhu. Sedangkan untuk analisis eksergi diawali dengan perancangan model pada masing­masing komponen dalam sistem pendingin adsorpsi intermitten. Hasil percobaan menunjukkan nilai kehilangan eksergi yang diperoleh untuk tiap proses dalam sistem pendingin adsorpsi. Nilai kerugian eksergi menggambarkan ketidak efektifan proses transfer energi dalam sistem pendinginan adsorpsi. Rincian hasil yang dicapai dari perhitungan dengan analisis eksergi memberikan data pada generator desorpsi kehilangan eksergi (exergy destroy) sebesar 35.33 Watt (90.57 %). Kondensor memberikan nilai sebesar 0.20 Watt (0.51 %). Evaporator memberikan nilai sebesar 0.07 Watt (0.18 %) dan pada generator adsorpsi memberikan nilai sebesar 3.51 %

PENGEMBANGAN TANAMAN JARAK PAGAR (Jatropha curcas L) MENDUKUNG KAWASAN MANDIRI ENERGI DI NUSA PENIDA, BALI

ABSTRAKDalam upaya memenuhi kebutuhan listrik di daerah terpencil danpulau-pulau kecil, pemerintah meluncurkan kebijakan pengembangan desamandiri energi. Di Nusa Penida, salah satu kawasan di Bali yang terdiriatas 3 pulau kecil, program mandiri energi dirancang dalam bentuk desawisata energi yang diwujudkan dengan pengembangan tanaman jarakpagar (Jatropha curcas L) sebagai penghasil bahan bakar nabati (BBN)untuk subtitusi bahan bakar pembangkit listrik tenaga diesel (PLTD).Analisis kebijakan pengembangan tanaman jarak pagar mendukungkawasan mandiri energi Nusa Penida dilakukan pada bulan Oktober 2007-April 2008. Penelitian ini bertujuan untuk: (1) mengkaji kesesuaian lahandan iklim Nusa Penida untuk pengembangan tanaman jarak, dan (2)melakukan analisis kelayakan finansial usahatani jarak pagar. Kesesuaianlahan dan iklim dianalisis secara deskriptif, sedangkan kelayakan finansialdianalisis berdasarkan kriteria investasi : NPV, B/C, dan IRR. Hasilpenelitian menunjukkan bahwa berdasarkan karakteristik iklim, wilayahNusa Penida termasuk ke dalam kriteria sesuai (S2) untuk pengembangantanaman jarak pagar. Unsur iklim yang menjadi pembatas adalahketersediaan air terutama pada bulan-bulan Agustus, September, danOktober yang merupakan puncak musim kemarau, sehingga waktu panenhanya berlangsung pada bulan Maret-Juli. Peran minyak jarak pagarmensubstitusi solar sebagai bahan bakar PLTD selain ditentukan olehwaktu panen, juga tergantung kepada harga biji jarak pagar yang dapatmemberikan insentif bagi petani untuk mengembangkan tanaman tersebut.Usahatani jarak pagar layak dikembangkan pada tingkat harga minimumRp 2.000/kg biji di tingkat petani.Kata kunci : Jatropha curcas L., kesesuaian lahan dan iklim, kelayakanfinansialABSTRACTPhysic Nut Jatropha curcas Development to SupportLocal Self-sufficient Energy in Nusa Penida, BaliTo fulfill the electricity requirement in remote areas and smallislands, Indonesian government runs the self-sufficient energy villageprogram. In Nusa Penida, an area that consists of three islands in BaliProvince, the program is run by developing Energy Tourism Area (ETA).In this program, physic nut (Jatropha curcas L.) was planted in the ETAand the seeds will be used for bio-diesel to substitute diesel powerelectricity generator fuel. A policy analysis of developing Jatropha curcasplantation in the ETA has been done in the period of October 2007 to April2008. The objectives of this research are : (1) to analyze the land andclimate suitability for planting physic nut, and (2) to analyze financialfeasibility of physic nut farming. The land and climate suitability analyzedby descriptive method. Financial feasibility analyzed by investmentcriteria : NPV, B/C ratio, and IRR. The result shows that the land andclimate in Nusa Penida is suitable (S2) for planting physic nut. The crucialelement of the climate is the availability of the water during dry season inAugust, September and October. The harvest season is in March to July.The role of physic nut as a source for bio-diesel is influenced by theharvest time and the price of physic nut seeds. A good price will lead thefarmer to maintain and develop their jatropha plantation.Key words : Jatropha curcas L., land and climate suitability, financialfeasibilit

Comparison of static-mixer and blade agitator reactor in biodiesel production

One of the difficulties faced in the current technology for biodiesel production is the requirement for rigorous mixing of methanol with the feedstock oil in the reactor.  Utilization of blade mixer is limited by the immiscible state of those substances.  This research is devoted to the assessment of static-mixer utilization in a transesterification reactor for biodiesel production in terms of kinetics reaction (reaction rate coefficient k, activation energy Ea, and collision factor or coefficient factor A).  The experiments were conducted by reacting palm oil (triglyceride or TG) with methanol (MeOH) at 50, 55, 60, 65, and 70℃, using potassium hydroxide (KOH) as catalyst.  Molar ratio of TG and MeOH was 1 : 10.5 and KOH used was 1% of palm oil weight.  Transesterification process using blade agitator with the same reaction condition was performed as base of comparison to those of static-mixer.  The experiments showed that static-mixer has significant effect in reducing reaction time to reach required fatty acid methyl ester content (FAME) i.e. 96.5% than those of blade agitator.  Transesterification reaction time with static-mixer is shorter than with blade agitator for all temperature levels.  Reaction temperature of 65℃ with five minutes of reaction time is demonstrated the best condition for running the static-mixer reactor.  The static-mixer and blade agitator experiments exhibited two stages transesterification that give the initial and the final activation energy (Ea1 and Ea2) and the initial and final collision factor (A1 and A2).  The value of Ea1, Ea2, A1, A2 for static-mixer experiments is 0.13 J/mol, 37.1 J/mol, 4.8, and 1,256, respectively.  Meanwhile the value of Ea1, Ea2, A1, and A2 for blade agitator experiments is   0.81 J/mol, 6.9 J/mol, 2.0 and 11.8, respectively.Keywords: static mixer, blade agitator, activation energy, utilization, biodiesel, collision factor, transesterification. Citation: Alamsyah, R., A. H. Tambunan, Y. Aris Purwanto, and D. Kusdiana.  Comparison of static-mixer and blade agitator reactor in biodiesel production.  Agric Eng Int: CIGR Journal. 2010, 12(1): 99-106.&nbsp