研究論文
超臨界水、製鉄スラッジ、転炉スラグ間反応による水素系ガス製造と製鉄発生物の再資源化技術
2007 年 33 巻 4 号 p. 187-192
詳細
2007 年 33 巻 4 号 p. 187-192
Automobile Shredder Residue (ASR) and Refuse derived fuels (not carbonized and carbonized: YRDF and RDF) as carbonaceous wastes were reacted isothermally with sub-supercritical water (600-695°C, 200 atm) together with a CO2 fixation reagent Ca(OH)2 inside a closed metallic tube reactor (7cm3). Product gas mainly consisted of hydrogen gas and a little methane gas except YRDF. As a whole, gas generated more in order ASR, YRDF, and RDF. Addition of catalysis NaOH or KOH made product gas increase more. KOH was more effective to product gas than NaOH. X-ray diffraction followed that Ca(OH)2 and CaCO3 existed mainly in residues after reaction tests with a CO2 fixation reagent Ca(OH)2 or CaO. Therefore, it was supposed that an overall chemical reaction took place as shown below. BOF steelmaking slag for CO2 fixation provided maximum gas generation 1.42 times as much as molar carbon in a RDF sample with KOH.
C + H2O + Ca(OH)2 = CaCO3 + 2H2
Two kinds of wastes from integrated steel mills (sludge from mill scale and activated sludge) were each reacted with supercritical water (600-650°C, 200 atm). Both sludges were effective to generate hydrogenous gas. It was found that harmful cyan in the latter sludge mostly decomposed after reaction. Also, the crushing strength after curing the steelmaking slag bearing residue briquette was not as high as that from Portland cement.
