• Clean Technology
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• v.24 no.2
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• pp.119-126
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• 2018

This study introduced a treatment process that was developed to treat Indonesian low-rank coal with high-ash content, which has the same characteristics as residual coal from the biosolubilization process. The treatment process includes separation of ash, solid-liquid separation, pelletizing, and drying. To reduce the ash content, flotation was performed using 4-methyl-2-pentanol (MIBC) as frother, and kerosene, waste oil, and cashew nut shell liquid (CNSL) as collectors. The increasing amount of collector had an effect on combustible coal recovery and ash reduction. After flotation, a filter press, extruder, and an oven drier were used to make a dried coal pellet. Then another coal pellet was made using asphalt as a binder. The compressive strength and friability of the coal pellets were tested and compared.

• KSBB Journal
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• v.7 no.1
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• pp.73-78
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• 1992

The solubilizations of Australian lignite by the fungus Poria cocos, Trichodermareesei, Candide tropicalis, and niger were investigated. Three different types of chemical pretreatment methods were used for increasing biosolubility of lignite. Nitric acid and hydrogen peroxide were proven to be proper chemical pretreatment materials of Australian lignite. Poria cocos showed much better solubilization ability than other strains. Interpretation of the nature of coal solubilization by Poria cocos was based primarily on infrared, ultraviolet and nuclear magnetic resonance spectrum analyses.

• KSBB Journal
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• v.11 no.4
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• pp.462-469
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• 1996

Biosolubilization of an Australian lignite was investigated by using Streptomyces viridosporus and Poria cocos. In order to solubilize coals effectively they were pretreated by nitric acid both in surface and liquid cultures. The optimum growth pH was 7.5 for S. viridosporus and 4.5 for P. cocos. The effects of various carbon, nitrogen and metal sources on overall solubilization were also studied. Solubility increased with the addition of urea for S. viridosporus, and peptone and tryptone for P. cocos. However carbon and metal sources had little or negative effects on solubilization. Maximum amount of coal solubilized was 85%(w/w) in a batch fermentation culture. Extracellular materials produced by micro-organism were found to be responsible for the coal solubilization. Approximately 70 to 80% of coal solubilization was determined to be the result of non-enzymatic reactions, and the rest to be the result of enzymatic reactions. Characteristics of the solubilized coal were compared with those of original coal and pretreated coal by the approximate and ultimate composition analysis, and IR-spectrum analysis. The spectroscopic results showed that the mechanism of coal solubilization was caused by continuous oxidation.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.4
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• pp.188-193
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• 2005

Pantoea agglomerans immobilized in alginate solubilized four different rock phosphates efficiently under in vitro conditions. The solubilization pattern differed according to the rock phosphate source, where maximum solubilization of Morocco and Tunisia rock phosphates (215.6 and $186.1mg\;P\;L^{-1}$) on 6 days, Israel rock phosphate ($60.98mg\;P\;L^{-1}$) and tricalcium phosphate ($132.3mg\;P\;L^{-1}$) on 10 days and China rock phosphate ($48.8mg\;P\;L^{-1}$) on 12 days after inoculation was observed. The shelf life of the immobilized bacteria immobilized beads stored in two different temperatures was studied for six months. Beads stored at both room temperature as well as cold storage ($4^{\circ}C$) were found equally good in supporting the bacterial population as well as phosphate solubilizing activity. P. agglomerans immobilized in alginate might be exploited for large scale biosolubilization of rock phosphates intended for fertilizer use.