The study of effects of

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Yogyakarta-Indonesia, 4-5

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December 2007

Chemical Engineering Department , Gadjah Mada University

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ISBN 978-979-16978-0-4

The Study Of Effects Of Electrolysis Variables To

The Inherent Moisture Content In Brown Coal

A. M.DJONI BUSTAN

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. B. MARDWITA

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Departement of Chemical Engineering University of Sriwijaya, Indonesia

a_{Graduate School University of Sriwijaya}

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Jalan Padang Selasa N0.524, Bukit Besar, Palembang 30139, Indonesia

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Telp: (0711)352132 – 354222 Fax : (0711) 317202 – 320310

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E-mail : djajashanta@yahoo.co.id

ABSTRACT

This research uses Electrothermal Dewatering Brown Coal (EDBC) technology to reduce the inherent moisture content in brown coal using kerosene as coal slurry medium maker. The purpode of this research is to learn the effect of voltage and process temperature to the increasing of coal product quality. From this research analysis of product at energy development and Mining Depatement of South Sumatera province shown that lowness inherent moisture product of experiment as 2.64% (adb) with beginning inherent moisture 12.09% (adb) that happen deriving inherent moisture as big as 78.16%. Lowness inherent moisture got from experiment use ratio of coal and kerosene at 1 : 2 and variable of electrolysis at 12 volts.

Keywords : Electrothermal dewatering brown coal technology, inherent moisture content, electrolysis.

I. INTRODUCTION

Indonesia is one of development country that try to reduce the crude oil consuming. With the potency of energy, Indonesia has no difficulty to subsitute crude oil. One of the energy is coal. The reserve in Indonesia is big enough 38.87 million tons or about 38% from total energy mix Indonesia [1]. Supporting from Energy and Mining Departement gives bright future for the use of coal. Main problem that occur in Indonesia mining is the water content in coal that cause the cost of transportation become expensive. Besides that, it makes the efficiency of burning become lower.

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II. RESEARCH METHOD

This research is used to analyze the effect of process variables to the increasing of brown coal (lignite) quality [8]. Generally this research consists of raw materials preparation, coal quality sampling analysis, electrothermal dewatering brown coal process (EDBC) and product analysis in laboratory. Coal particle ± 50 mesh, coal-kerosene ratio are 1:10, 1:20, and 1:40. The kerosene compound can reach inside the coal structure, after 15 minutes circulated process, kerosene and coal particle will be separated by the density for 1 hour aglomeration. Wet coal as product is dried by the temperature 160 oC for 2 hours and the product will be analyzed in laboratory to find out the inherent moisture content.

Waste water sinusoidal pattern as a electrical wave from electrolysis resources process. The percentage of inherent moisture content is being different for each coal ratio caused by electron suppy from electrolysis process.

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Fig 1.2. Electrolyse variable (voltage) to decreasing inherent moisture content (%adb) Process temperature 50 oC

Slurry making Water Reducing Coal-kerosene

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Yogyakarta-Indonesia, 4-5

th

December 2007

Chemical Engineering Department , Gadjah Mada University

14

TH

R

EGIONAL

S

YMPOSIUM ON

C

HEMICAL

E

NGINEERING

2007

ISBN 978-979-16978-0-4

IV. CONCLUSIONS

Electrolysis give significant effect to the decreasing of inherent moisture content and increasing of coal heating value . The highest decreasing of inherent moisture content is at coal-kerosene ratio 1: 20, temperature 70 oC and voltage 12 volts with percentage of decreasing achieved 78.16%.

REFERENCES

[1] Almu’minin Syarif, 2005, “Pengaruh Thermal Dewatering Batubara terhadap Kualitas Batubara”, Laporan Tugas Akhir Jurusan Teknik Pertambangan Fakultas Teknik Universitas Sriwijaya, Inderalaya. [2] Evans D.G.; and Seimon S.R. 1979. US patent number 3.552.031

[3] Syarifudin and Rr. Herminuke E.H, 2004 “Quality Improvement of Musi Bayuasin Low Rank Coal with

Deriving Inherent Moisture In Upgraded Brown Coal Process” Proceding of HEDS Seminar on Science &

Tecnology, Jakarta.

[4] Chaffe dan I Yarovshy, 2005, “The Chemistry of Coal-Water Interactions: and Theoritical and Experimentl

Investigation”, CRC for Clean Power from Lignit, Monash University dan RMIT University, Melbourne.

[5] T. Deguchi, T. Shigehisa and K. Shimasaki, 1999, “Study on Upgrading Brown Coal Process for

Indonesian Low Rank Coal”, Kobe Steel, Ltd., Procedings of 10th ICCS, Jepang.

[6] Meyers, Robert. A, 1981, “Coal Handbook”, Marcell Dekker. Inc, New York.

[7] Berkowitz. N, 1985, “The Chemistry of Coal: Coal Science and Technology”, Volume 2, Elvessier Publicatin.Co, Amsterdam.