Project/Area Number |
03650536
|
Research Category |
Grant-in-Aid for General Scientific Research (C)
|
Allocation Type | Single-year Grants |
Research Field |
金属精錬・金属化学
|
Research Institution | Institute for Advanced Materials Processing, Tohoku University |
Principal Investigator |
TOKUDA Masanori Institute for Advanced Materials Processing, Tohoku University, Professor, 素材工学研究所 (30006027)
|
Co-Investigator(Kenkyū-buntansha) |
UCHIDA Satoshi Institute for Advanced Materials Processing, Tohoku University, Research Associa, 素材工学研究所, 助手 (60232849)
|
Project Period (FY) |
1991 – 1992
|
Project Status |
Completed (Fiscal Year 1992)
|
Budget Amount *help |
¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 1992: ¥400,000 (Direct Cost: ¥400,000)
Fiscal Year 1991: ¥1,600,000 (Direct Cost: ¥1,600,000)
|
Keywords | Hydrothermal / Coal / Alkaline / Extraction / Pre treatment / Sodium hydroxide / Calcium hydroxide / Autoclave / 石炭 / クリ-ンエネルギ- / 脱灰分 / アルカリ水熱反応 / 脱燐 / 溶解度 |
Research Abstract |
The extraction behavior of mineral impurities from Brazilian coal was investigated from 180 to 250゚C in the Ca(OH)_2/NaOH solution...Among them, removal of phosphorus was better realized than other inert matters. The phosphorus extraction reached the highest results at lower temperatures between 180゚C and 200゚C. It was also found that lower concentrations could give better results; especially in the case of Ca(OH)_2. Using Ca(OH)_2, the better concentration range was considered to be from 0.5 mol/kg-H_2O to 1.0 mol/kg-H_2O. NaOH 2.0 mol/kg-H_2O leads more phosphorus to be removal. In the case of NaOH, significant lost of coal matter was observed either for the temperature increasing or for the concentration increasing. When the temperature goes up more than 200゚C, the calcium-phosphate complexes convert into hardly soluble matter such as hydroxyl apatite and turn back to the residue again. The SiO_2 and Al_2O_3 behaviors are quite similar: the higher the temperature and the reagent concentration, the higher the extraction degree of SiO_2 and Al_2O_3 in the case of NaOH. In addition, the increasing of temperature can promote more removal of SiO_2. The Ca(OH)_2 was not effective for SiO_2 and Al_2O_3 extraction. Compared the effects of Ca(OH)_2 and NaOH, Ca(OH)_2 showed more promising results. Furthermore, Ca(OH)_2 is much suitable than NaOH in the production factory. Nevertheless at atmospheric pressure conditions, hot water bath, NaOH is better than Ca(OH)_2 for removing phosphorus.
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