摘要
采用低温对流脱水工艺对神华集团金烽煤矿的高含水低变质程度煤进行干燥,实验研究了煤在脱水过程中被热空气氧化的规律并优化出最佳的干燥工艺条件。采用XPS对脱水前后的煤样表面碳元素的价态进行分析,结果表明:用170℃热空气脱水10min可将煤的全水分从30%降至15%以下,低位发热值从18.63MJ/kg提高到23.51MJ/kg;随着热空气温度的升高和脱水时间的延长,煤的脱水活化能增加,吸氧增重活化能降低,煤样表层碳元素的C-H/C-C键比例逐渐减少,而氧化产物C-O键和羰基逐渐增多,煤氧复合反应的速度逐渐加快,煤在脱水过程中的氧化程度加深,自热和自燃的倾向性增强。
In this paper,the low-temperature convective drying technique for high-moisture low rank coal was carried out.And the oxidation law of the coal in the drying process was studied,and the different drying conditions on the oxidation and spontaneous combustion properties of coal was discussed.The analysis of carbon state on coal surface befor and after drying by XPS show that the water in the coal can be reduced from 30% to 15%,and low-level heating power increases from 18.63MJ/kg to 23.51MJ/kg under the condition of drying 10 min with 170 ℃ hot air.The C-C or C-H bands of the coal surface will decrease but the oxidized production such as C-O band and carbonyl group will in crease.All these changes are show that the coal dehydration was inconvenience gradually;the degree of oxidation of the coal was improved on the dryness process.It will increase the risk of spontaneous combustion of the coal.
出处
《煤炭技术》
CAS
北大核心
2010年第5期189-191,共3页
Coal Technology
关键词
低温干燥
煤
氧化
XPS
low-temperature drying
coal
oxidation
XPS
