2002 Fiscal Year Final Research Report Summary
Improvement of Energy Use Efficiency and Reduction of Environmental Load by Upgrading of Unused Low Rank Coal
| Project/Area Number |
12450409
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
資源開発工学
|
|---|
| Research Institution | HOKKAIDO UNIVERSITY |
|---|
Principal Investigator |
HIRAJIMA Tsuyoshi Hokkaido Univ., Graduate School of Eng, Associate Professor, 大学院・工学研究科, 助教授 (00175556)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
SASAKI Keiko Otaru University of Commerce, Associate Professor, 商学部(環境科学), 助教授 (30311525)
HIROYOSHI Naoki Hokkaido Univ., Graduate School of Eng, Instructor, 大学院・工学研究科, 助手 (50250486)
TSUNEKAWA Masami Hokkaido Univ., Graduate School of Eng, Professor, 大学院・工学研究科, 教授 (40002026)
FUKUSHIMA Masami National Institute of Advanced Industrial Science and Technology, Chief Researcher, つくば西事業所・環境管理研究部門, 主任研究員
|
|---|
| Project Period (FY) |
2000 – 2002
|
| Keywords | Low Rank Coal / Hot Water Drying / Upgrading / Flotation / Oil Agglomeration / Chemical Cleaning / Sexivalent Chrome / Reduction |
|---|
| Research Abstract |
Hot water drying (HWD) treatment was carried out at different temperatures such as 270, 300 and 330℃. With increasing temperature water content and carboxyl content of the both coals were decreased and their floatability became higher. Combustible matter recovery of the HWD treated coals by flotation was 20-30% higher than that of the raw coals and the ash content of the froth product was lower for the treated coals than the raw coals. Products containing 4.1-4.3% ash were also recovered by oil agglomeration of the fine HWD treated Beluga coals. Chemical coal cleaning method of the HMD treated coals with aqueous caustic process leads to a drastic decrease in ash content with a high recovery of combustible matter than that of raw coal. The ultra clean coal with 0.5% ash and 86% recovery of combustible matter was produced by a combination of three treatments such as the HWD, flotation and chemical cleaning.
Liquid products produced in a HWD process were characterized by GC/MS, HPLC, GPC,
… More
TOC measurement and cyclic voltammetry. The ability of the liquid products to reduce Cr(VI) was investigated by analyzing solutions containing the liquids and Cr(VI), and by fluorescence spectrometry. With increasing treatment temperature TOC concentration of the liquid products became larger. The liquid product at 270℃ contained acetic acid, acetic acid-methyl ester and oligomer of mass weight 1600-3400. The liquid product at 300℃ and 330℃ contained catechol and phenol, and the latter product included more catechol groups. The reduction behavior of both liquids obtained above 300℃ was similar to that of catechol in cyclic voltammetry.
All liquid products reduced the Cr(VI) to Cr(III), and their reduction ability became stronger with decreasing pH. For a solution containing high Cr(VI) concentration the liquid obtained at 330℃ successfully reduced Cr(VI) below the allowed level at pH 2. It was found by fluorescence spectroscopy that Cr(VI) was reduced to catechol groups in the liquid products. Less
|
