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KAJIAN EKSPERIMENTAL KELAYAKAN DAN PERFORMA ALAT PENUKAR KALOR TIPE SHELL AND TUBE SINGLE PASS DENGAN METODE BELL DELAWARE

Prosiding Seminar Nasional Sains Dan Teknologi Fakultas Teknik Vol 1, No 1 (2012): PROSIDING SEMINAR NASIONAL SAINS DAN TEKNOLOGI 3 2012
Publisher : Prosiding Seminar Nasional Sains Dan Teknologi Fakultas Teknik

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Abstract

Peranan Alat Penukar Kalor dalam industri sangat besar, misalnya dipergunakan pada industri makanan, pembangkit tenaga listrik, perminyakan, transportasi, pendingin dan pemanas, dll. Pada umumnya Alat Penukar Kalor berperan dalam peningkatan efisiensi sistem. Penelitian ini bertujuan untuk mengetahui performa Alat Penukar Kalor tipe Shell and Tube Aliran Tunggal dengan Metode Bell Delaware. Penelitian dilakukan di Lab Konversi Energi PSD III Teknik Mesin Undip secara ekperimental dengan laju aliran pada shell sebesar 5 lpm dan laju aliran pada tube sebesar 10 lpm. Dari hasil perhitungan data diperoleh hasil bahwa nilai effectiveness peralatan adalah berkisar antara 0,4 – 0,5. Sedangkan nilai koefisien perpindahan kalor total alat penukar kalor 132,618 W/m2K.Kata kunci: penukar kalor, shell and tube single pass, bell delaware

AUDIT ENERGI PADA SEBUAH HOTEL

GEMA TEKNOLOGI Vol 16, No 3 (2011): Periode April 2011 - Oktober 2011
Publisher : GEMA TEKNOLOGI

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Abstract

Didik Ariwibowo, in this paper explain that energy audit activities conducted through several phases, namely: the initial audit, detailed audit, analysis of energy savings opportunities, and the proposed energy savings. Total energy consumed consists of electrical energy, fuel, and materials in this case is water. Electrical energy consumption data obtained from payment of electricity accounts for a year while consumption of fuel and water obtained from the payment of material procurement. From the calculation data, IKE hotels accounted for 420.867 kWh/m2.tahun, while the IKE standards for the hotel is 300 kWh/m2.tahun. Thus, IKE hotel included categorized wasteful in energy usage. The largest energy consumption on electric energy consumption. Largest electric energy consumption is on the air conditioning (AC-air conditioning) that is equal to 71.3%, and lighting and electrical equipment at 27.28%, and hot water supply system by 4.44%. Electrical energy consumption in AC looks very big. Ministry of Energy and Mineral Resources of the statutes, the profile of energy use by air conditioning at the hotel by 48.5%. With these considerations in the AC target for audit detail as the next phase of activity. The results of a detailed audit analysis to find an air conditioning system energy savings opportunities in pumping systems. Recommendations on these savings is the integration of automation on the pumping system and fan coil units (FCU). The principle of energy conservation in the pumping system is by installing variable speed drives (VSD) pump drive motor to adjust speed according to load on the FCU. Load variations FCU provide input on the VSD pumps to match. Adaptation is predicted pump can save electricity consumption up to 65.7%. Keywords: energy audit, IKE, AC

MODEL PERPINDAHAN MASSA PROSES STEAMING INAKTIVASI ENZIM POLIFENOL OKSIDASE DALAM PENGOLAHAN TEH HIJAU

GEMA TEKNOLOGI Vol 15, No 1 (2006): Periode April - Oktober 2006
Publisher : GEMA TEKNOLOGI

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Abstract

Mohamad EndyYulianto, Didik Ariwibowo, Fahmi Arifan, Heni Kusumayanti, F.S. Nugraheni, Senin, in paper mass transfer model in inactivation steaming process of ocsidase polifenol enzim at green tea processing explain that tea is natural herbs for freshner and maintain body’s heart drinking because it contains catechin the bioactives agent that can prevent cancer, heart failure, myocardial infarction, eases the bowel movement, prevent infection of mouth, gum and so on. Because of it’s the high catechin is needed. The get high catechin the enzymatic oxidation of polifenol must be undergone. For the reason its needed to study an inactivated process of polifenol oxsidase enzyme by steaming. However, this process will depend on mass transfer behavior and pattern of steam penetration into tea leaves. It is effident because of its properties will influence catechin contain in fresh tea leaves. Mass transfer model of inactivation for polifenol oxsidase enzyme in high catechin green tea processing by steamingKey word : mass transfer, steaming, green tea

STUDI AWAL REKAYASA PROSES PRODUKSI TEH HIJAU BERKATEKIN TINGGI MELALUI TEKNOLOGI STEAMING

METANA Volume 4 Nomor 1 Juni 2007
Publisher : METANA

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Abstract

Abstract Tea is a nalural healty, beverage because of catechin content which is a bioactive matter that can retard cancel growth, heart desease, blood and nerves, making healthy for mouth, teeth and some other infection. Therefore, high catechin in tea would be needed. To Obtain high catechin contend it must eliminate enzymatically oxidation process of polyphenol during tea manufacturing. Thus, it was created a process and processing system which sustain the process. The basic design was inactivation of polyphenol oxidase enzyme by steaming. It wishes a high catechin green tea product that can either be directly as a beverage or as a catechin powder for dietary food and functional food or medicine. The variables of this study, were percentage of steam, tea leaves feeding and humidity. The investigated parameters were temperature, catechin content, moisture content, and humidity as time function. The result was that at 900C yielded high catechin. The study shows that at 70%  humidity  yielded higher catechin and lower moisture content.   Keywords : Green tea; Steaming

PERFORMA MESIN DIESEL BERBAHAN BAKAR BIODIESEL TEROKSIDASI

Prosiding Seminar Nasional Sains Dan Teknologi Fakultas Teknik Vol 1, No 1 (2011): PROSIDING SEMINAR NASIONAL SAINS DAN TEKNOLOGI 2 2011
Publisher : Prosiding Seminar Nasional Sains Dan Teknologi Fakultas Teknik

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Abstract

Penelitian ini bertujuan untuk mendapatkan informasi performa mesin diesel berbahan-bakar biodiesel teroksidasi dibandingkan dengan mesin diesel berbahan-bakar solar. Pengujian dilakukan pada mesin diesel izusu C223. Biodiesel dibuat dari minyak goreng curah dengan proses transesterifikasi. Kemudian, biodiesel tersebut dioksidasi dengan proses aerasi. Sifat-sifat biodiesel diukur antara lain bilangan peroksida, angka setana, dan kandungan energi. Torsi mesin diukur dengan water brake dynamometer, sedangkan konsumsi bahan bakar diukur dengan gelas ukur.  Performa mesin ditentukan oleh brake specific fuel consumption, bsfc, yang merupakan kalkulasi konsumsi bahan bakar dibagi dengan daya brake. Hasil penelitian menunjukkan bahwa bahan bakar biodiesel teroksidasi mempunyai karakteristik pembakaran lebih baik dibandingkan dengan solar, pada rentang beban kecil sampai dengan menengah, yang diindikasikan dengan daya yang lebih besar daripada solar yaitu sebesar 12,37%. Namun, bsfc dari bahan bakar tersebut lebih tinggi 4,84% daripada solar. Pemakaian B20 biodiesel-teroksidasi/solar merupakan pemakaian terbaik pada penelitian ini. Campuran B20 untuk biodiesel-teroksidasi/solar mempunyai daya lebih tinggi 16,2% dan bsfc lebih rendah 11,2% dibandingkan dengan solar. Pemakaian B100 biodiesel-teroksidasi tidak memberikan performa yang lebih baik pada mesin diesel. Kata kunci: performa, mesin diesel, brake specific fuel consumption

PEMODELAN DAN SIMULASI PROSES PENGERINGAN CHIPS MOCAF

METANA Vol 8, No 02 (2012): Volume 8 No.02 Desember 2012
Publisher : METANA

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Abstract

This study was to propose the use of a simple heat and mass transfer based model to predict the evolutions of the moisture content and temperature of cassava chip undergoing superheated steam drying (SSD). Cassava chip has been chosen as the product to be simulated because of its various uses in the food especially as modified cassava flour (mocaf). Recently, superheated steam drying (SSD) has received much attention as an alternative drying technique for heat-sensitive biomaterials. There are a very limited number of works that report attempts to model this drying process, although there are a number of works that report studies of this drying technique experimentally. The results showed that the drying of the product is affected by the drying steam temperature and the product characteristics. The model was found to be able to predict the heat and mass transfer behavior. Keywords: Cassava chip, mocaf, superheated steam drying

PEMODELAN DAN SIMULASI PROSES PENGERINGAN CHIPS MOCAF

METANA Vol 8, No 02 (2012): Volume 8 No.02 Desember 2012
Publisher : METANA

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Abstract

This study was to propose the use of a simple heat and mass transfer based model to predict the evolutions of the moisture content and temperature of cassava chip undergoing superheated steam drying (SSD). Cassava chip has been chosen as the product to be simulated because of its various uses in the food especially as modified cassava flour (mocaf). Recently, superheated steam drying (SSD) has received much attention as an alternative drying technique for heat-sensitive biomaterials. There are a very limited number of works that report attempts to model this drying process, although there are a number of works that report studies of this drying technique experimentally. The results showed that the drying of the product is affected by the drying steam temperature and the product characteristics. The model was found to be able to predict the heat and mass transfer behavior. Keywords: Cassava chip, mocaf, superheated steam drying

PENGEMBANGAN ADSORBENT BED UNTUK PENINGKATAN KONDUKTIVITAS TERMAL MELALUI PENAMBAHAN PARTIKEL METAL ALUMINIUM

Prosiding Seminar Nasional Sains Dan Teknologi Fakultas Teknik Vol 1, No 1 (2014): PROSIDING SEMINAR NASIONAL SAINS DAN TEKNOLOGI 5 2014
Publisher : Prosiding Seminar Nasional Sains Dan Teknologi Fakultas Teknik

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Abstract

Penelitian ini dimaksudkan untuk meningkatkan konduktivitas termal adsorbent dengan cara memberikan penambahan butiran metal ke dalam adsorbent bed sehingga menjadi suatu campuran butiran dalam suatu bed. Adsorbent bed berisi butiran karbon aktif dan partikel metal aluminium. Kegiatan yang dilakukan meliputi: desain dan pabrikasi prototipe adsorbent bed, dilanjutkan studi perfroma termal dari adsorbent bed. Studi perfroma termal dari adsorbent bed meliputi: studi pengaruh rasio metal/adsorben pada konduktivitas termal dari adsorbent bed. Parameter yang diteliti adalah rasio metal/adsorben (5, 10, 15% berat). Hasil penelitian menunjukkan bahwa penambahan partikel aluminium meningkatan nilai konduktivitas termal adsorbent bed sebesar 10,9 Wm-1K-1; 21,9 Wm-1K-1; dan 30,9  Wm-1K-1 pada penambahan volume partikel aluminium 5%, 10%, dan 15% yang dibandingkan dengan adsorbent bed karbon aktif yang memiliki nilai konduktivitas termal 1,6 Wm-1K-1. Nilai konduktivitas termal hasil eksperimen lebih tinggi daripada nilai konduktivitas termal kalkulasi. Persentase perbedaan tersebut menurun seiring dengan meningkatnya temperatur permukaan bed. Persentase perbedaan yang relatif tinggi berkisar pada nilai 45%, sedangkan perbedaan yang relatif rendah berkisar pada 10%. Rentang perbedaan yang rendah yaitu 10-20% terjadi pada rentang temperatur 55-65 oC. Kata kunci: adsorbent bed, rasio metal/adsorben, konduktivitas termal

PENGEMBANGAN ADSORBENT BED UNTUK PENINGKATAN KONDUKTIVITAS TERMAL MELALUI PENAMBAHAN PARTIKEL METAL ALUMINIUM

GEMA TEKNOLOGI Vol 17, No 4 (2014): Periode Oktober 2013 - April 2014
Publisher : GEMA TEKNOLOGI

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Abstract

Didik Ariwibowo, Sutrisno, in this paper explain that this research is to increase thermal conductivity of a adsorbent bed by adding metal particles in it so that the bed become a granule-mixed bed. The adsorbent bed contains activated-carbon granule and aluminium particles. The research activity include: design and fabrication of adsorbent bed prototype following thermal performance study of the adsorbent bed. The thermal performance study of the adsorbent bed was conducted by varying metal/adsorbent ratio of 5%, 10%, 15% by volume. The result showed that adding 5%, 10%, and 15% aluminium particles into adsorbent bed has increased its thermal conductivity, those are 10,9 Wm-1K-1; 21,9 Wm-1K-1; and 30,9  Wm-1K-1 respectively from 1,6 Wm-1K-1 activated carbon thermal conductivity. The values of experimental thermal conductivity were higher than those of calculated thermal conductivity. The percentage of the difference between experimental thermal conductivity and calculated thermal conductivity decreased as bed surface temperature increased. The relatively higher percentage was in 45% whereas the lower was 10%. The lower range of the difference was 10-20% occurred in 55-65 oC temperature range. Key words: adsorbent bed, metal/adsorbent ratio, thermal conductivity

KARAKTERISTIK ALAT PENEPUNG DISC MILL FFC-XX UNTUK PENEPUNGAN TONGKOL JAGUNG KERING

ROTASI Vol 18, No 3 (2016): VOLUME 18, NOMOR 3, JULI 2016
Publisher : Jurusan Teknik Mesin, Fakultas Teknik, Universitas Diponegoro

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Abstract

Sisa tanaman pertanian yang cukup melimpah tetapi masih jarang digunakan sebagai bahan ransum pakan hewan adalah tongkol jagung. Pengurangan ukuran partikel pakan dengan cara penggilingan kemudian dibuat pelet merupakan salah satu perlakuan pradigesti pada pakan berserat secara fisik yang mampu meningkatkan kecernaan. Alat penepung tipe disc mill merupakan alat penggiling yang telah banyak diproduksi secara komersial. Namun, karakteristik disc mill terhadap bahan umpan perlu diinvestigasi terkait dengan kapasitas produksi dan konsumsi energi spesifik untuk bahan dengan tingkat kekeringan tertentu. Riset ini bertujuan untuk menginvestigasi karakteristik suatu alat penepung tipe disc mill FFC-XX untuk memproduksi tepung dari bahan tongkol jagung. Tongkol jagung yang diumpankan memiliki kandungan air (moisture content - MC) 22% dan 33%. Tongkol jagung digiling menjadi tepung dengan ukuran mesh-20, mesh-25, dan mesh-80. Karakteristik yang dideskripsikan yaitu kapasitas produksi (kg/jam) dan konsumsi bahan bakar spesifik (Liter/kg). Analisis sidik ragam menunjukkan bahwa kandungan air bahan umpan berefek pada perbedaan kapasitas produksi pada mesh-20 dan mesh-25. Kapasitas produksi pada mesh-20 berturut-turut adalah 8,44 kg/jam untuk MC 22 dan 10,61 kg/jam untuk MC 33, dan pada mesh-25 berturut-turut adalah 10,36 kg/jam untuk MC 22 dan 11,98 kg/jam untuk MC 33. Namun pada mesh-80, kandungan air tidak berefek pada perbedaan kapasitas. Kapasitas produksi pada mesh-80 berada pada rentang 1,95 kg/jam - 2,15 kg/jam. Analisis sidik ragam pada konsumsi bahan bakar spesifik (L/kg) menunjukkan bahwa konsumsi bahan bakar spesifik berbeda pada pengoperasian alat dengan mesh-25. Pada mesh tersebut, konsumsi bahan bakar spesifik adalah 0,1 L/kg untuk MC 22 dan 0,07 L/kg untuk MC 33