Jurnal Puslitbang tekMira (Teknologi Mineral dan Batubara)
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THE EFFECT OF HYDROGEN PRESSURE ON THE PREPARATION OF ARTIFICIAL CAKING COAL FOR COKE BINDER
No full textBinder of carbon compounds can be made through hydrogenation process and/or coal extraction. Hydroge- nation of coal converts the steam coal into caking one which functions as a binder or additive in the making of coke while the extraction of coal produces good quality pitch. Some coals from Tanito Harum, Baramarta and Bukit Asam were used as raw materials for binder making. Observations included effect of hydrogen pressure on the total carbon and ash contents and free swelling index as well. Coal hydrogenation was performed in a 5-litre batch type autoclave at reaction temperature of 400oC. The initial hydrogen pressure varies from 5 to 30 bars and to 1 hour reaction time. The next stage was the distillation of hydrogen product. It can be concluded that all non-caking coals used in the experiments can be converted into caking coal to be used as a binder in the coke making. The ash content within coal considerably affects the resulting binder product; binder that has low ash content is preferred
ALTERNATIVE METHOD OF THE ACTIVATION PROCESS FOR BENTONITE MINERAL
No full textBiodiesel manufacture usually applies liquid catalyst (homogenic catalyst) that deals with some obstacles, such as difficulty in catalyst product separation as they are in the same liquid phase, corrosive characters, excessive catalyst cannot be reused, and complicated to be handled. An alternative for a better process is solid catalyst as a heterogeneous system between raw material and product. Bentonite has layer structures and a potential to be used as solid catalyst by activation process. Three methods of activation process had been conducted,namely 60°C-heating; 60°C-heating followed by 1 week settling and 2 weeks settlement. Each method was performed in sulphuric acid and the chemical content of Al2O3 and SiO2 was observed. An activated bentonite has a molar ratio of SiO2 and Al2O3 between 6 - 9. All methods resulted in expected molar ratio, but the 2 weeks settlement process without heating provided more significant result which means it performed energy saving compared to other methods
BARIUM CONCENTRATION IN DEEP SEA SURFACE SEDIMENTS FROM TOMINI BASIN: VERTICAL DISTRIBUTION AND OCCURRENCE
No full textThe concentrations of trace elements (Th, Zr, Ba, Ce, Nb and Sr) in the sediments core from Tomini Basin, Sulawesi were studied to establish their vertical distributions and occurrence. However, the highest concen- tration of trace elements was dominated by barium (>300 ppm). Results indicate that barium composition in the surface sediments generally increase downward. Vertical distribution of barium in Tomini Basin indicates that its sedimentary environment has a high palaeo-productivity
ANALYSIS OF SMALL-SCALE MINING IN MINERAL AND COAL MINING LAW NUMBER 4/2009 (INPUTS FOR FORMULATION OF IMPLEMENTING REGULATION)
No full textLaw Number 4/2009 on Mineral and Coal Mining has been approved by the DPR (the Indonesian Parlia- ment) and issued by the government on January 12, 2009. Explicitely, small-scale mining is regulated by the law and the upcoming governmental decree that regulates its implementation to be issued in 2010, followed by the ministrial decree and regional regulation. In the meantime, illegal mining activites (PETI - Pertambangan Tanpa Izin) reported everywhere in Indone- sia. It reminds us on the case of tremendous environmental disaster due to illegal gold mine in Central Kalimantan, inconventional tin mine in Bangka Belitung, illegal coal mine in South Kalimantan, and illegal mine of industrial mineral (C Group minerals) in all areas in Indonesia. The current question is will those dissaters happen again and can the Law Number 4/2009 prevents it from happening? Analysis on the law identifies that the law needs to be clarified with implementing regulations that, among others, regulate the small-scale’s mining area, small-scale mining authorization, the right and responsibility of mining authorization holder, transfer of authority to head of district, the right of mining authorization holder over the land, etc
STUDY OF POLYMETHACRYLATE (PMA) INFLUENCE AS DISPERSANT ON UBCWM PREPARATION
No full textUpgraded brown coal water mixture (UBCWM) is a mixture of coal resulted from upgraded brown coal (UBC) process with water in a certain ratio to form a homogeneous and stable suspension during storage, transpor- tation and combustion. UBCWM can be used as direct fuel as substitute for heavy fuel oil, particularly in industrial boilers. To obtain a UBCWM with high coal concentration and low apparent viscosity as well as good flow characteristics, the addition of additive as dispersant is needed. To study the effectiveness of polymethacrylate (PMA) as dispersant, research on the effect of PMA in the production of UBCWM needs to be carried out. The research was conducted by preparing UBCWM with the addition of PMA of 0.1, 0.3 and 0.5% and also carboxymethyl cellulose (CMC) of 0.01% as stabilizer. Preparation of UBCWM using 0.3% PMA and CMC, xantham gum (S- 60) and ransham gum (S-194) of 0.01% each was also carried out. Flow characteristic of the UBCWM was measured by using a viscometer at various shear rate. Results indicate that the addition of 0.3% PMA in the production of UBCWM is effective as dispersant. The addition of 0.5% PMA did not significantly reduce apparent viscosity. The addition of 0.3% PMA together with 0.01% CMC produces UBCWM with the highest coal concentration of 58.3% with yield stress of 23.22 Pa
MACERAL AND MINERAL ANALYSIS OF LEBAK COALS REGARDING THEIR UTILISATION
No full textType and rank variations of Lebak coals were derived from twenty-eight samples of Palaeogene coalfield (Bayah, Cimandiri and Cihideung) and Neogene coalfields (Bojongmanik) using petrographic analy- ses. The Lebak coals are dominated by vitrinite, liptinite and minor inertinite and mineral matter as well. The coal type, in terms of maceral and mineral compositions, reflects climatic influences and differences in peat conditions. Higher vitrinite reflectance of Palaeogene coals, compared to Neogene ones, is a result of higher regional coalification level in the basin, associated with greater cover and local effect of igneous intrusion. The Palaeogene coals have better quality than the Neogenes and is also supported by higher specific energy. The coals that are vitrinite-rich, liptinite and inertinite-poor are suitable for direct combustion