The Fluorine release rate of coal, clay of different Fluorine content, and coal mixed with clay used by resident households were studied by using the ion selective electrode （ISE） and solidoid balance methods, and t...The Fluorine release rate of coal, clay of different Fluorine content, and coal mixed with clay used by resident households were studied by using the ion selective electrode （ISE） and solidoid balance methods, and the degree of influence on Fluorine pollu- tion generated by coal and clay was analyzed according to the proportion characteristics of coal used by resident households. The results show that the Fluorine release rate of coal is more than 95% during combustion; The Fluorine release rate of clay is more than 99%; The Fluorine release rate of coal mixed with clay is between 56.44% and 96.64%, and the average value is 76.68%. The clay as a binder for fine coal is one important source of Fluorine pollution caused by coal-combustion in Zhaotong, Yunnan Province. When the Fluorine content of coal is less than 80 mg/kg, the F[uodne amount released from clay （in which Fluorine content is more than 530 mg/kg） is more than 50% of the total Fluorine amount released from coal and clay during coal-combustion. The Fluorine amount released from clay （in which Fluorine content is more than 1 000 mg/kg） is more than 70% of total Fluorine amount released from coal and clay during coal-combustion.展开更多
The release characteristics of CH_(4),H_(2),CO and CO_(2) from iron coke hot briquette(ICHB)during carbonization were studied.The results show that compared with briquette without iron ore,Fe_(3)O_(4) can inhibit the ...The release characteristics of CH_(4),H_(2),CO and CO_(2) from iron coke hot briquette(ICHB)during carbonization were studied.The results show that compared with briquette without iron ore,Fe_(3)O_(4) can inhibit the release rate of H2 and promote the production of CO and CO_(2).In addition,when the heating rate increases from 3 to 7℃/min,the release rates of CH4 and H2 increase,while the release rates of CO and CO_(2) first increase and then decrease.The carbonization process of ICHB was segmented,and corresponding kinetic analysis was carried out.The results show that the activation energy of StageⅡand StageⅣis higher in the carbonization process of ICHB,and the active pyrolysis of coal and the reduction of iron ore occur in these two stages.In addition,the effect of heating rate on the kinetic parameters of ICHB carbonization process was investigated.It was found that when the heating rate increased,the reaction activation energy of StageⅣdecreased first and then increased,which was consistent with the release law of CO and CO_(2).The analysis showed that the increase in heating rate leads to more reactions at higher temperatures,resulting in an increase in the release rate of some gases.In addition,thermal hysteresis can also cause some processes to fail to fully react at the end of heating.It is also found that the apparent activation energy and preexponential factor have kinetic compensation effect during the car-bonization of ICHB.展开更多
基金Supported by the National High-Tech Research and Development Program of China(2006AA06Z380)the National Natural Science Fundation of China(40872210)Western Key Fund(90202017)
文摘The Fluorine release rate of coal, clay of different Fluorine content, and coal mixed with clay used by resident households were studied by using the ion selective electrode （ISE） and solidoid balance methods, and the degree of influence on Fluorine pollu- tion generated by coal and clay was analyzed according to the proportion characteristics of coal used by resident households. The results show that the Fluorine release rate of coal is more than 95% during combustion; The Fluorine release rate of clay is more than 99%; The Fluorine release rate of coal mixed with clay is between 56.44% and 96.64%, and the average value is 76.68%. The clay as a binder for fine coal is one important source of Fluorine pollution caused by coal-combustion in Zhaotong, Yunnan Province. When the Fluorine content of coal is less than 80 mg/kg, the F[uodne amount released from clay （in which Fluorine content is more than 530 mg/kg） is more than 50% of the total Fluorine amount released from coal and clay during coal-combustion. The Fluorine amount released from clay （in which Fluorine content is more than 1 000 mg/kg） is more than 70% of total Fluorine amount released from coal and clay during coal-combustion.
文摘The release characteristics of CH_(4),H_(2),CO and CO_(2) from iron coke hot briquette(ICHB)during carbonization were studied.The results show that compared with briquette without iron ore,Fe_(3)O_(4) can inhibit the release rate of H2 and promote the production of CO and CO_(2).In addition,when the heating rate increases from 3 to 7℃/min,the release rates of CH4 and H2 increase,while the release rates of CO and CO_(2) first increase and then decrease.The carbonization process of ICHB was segmented,and corresponding kinetic analysis was carried out.The results show that the activation energy of StageⅡand StageⅣis higher in the carbonization process of ICHB,and the active pyrolysis of coal and the reduction of iron ore occur in these two stages.In addition,the effect of heating rate on the kinetic parameters of ICHB carbonization process was investigated.It was found that when the heating rate increased,the reaction activation energy of StageⅣdecreased first and then increased,which was consistent with the release law of CO and CO_(2).The analysis showed that the increase in heating rate leads to more reactions at higher temperatures,resulting in an increase in the release rate of some gases.In addition,thermal hysteresis can also cause some processes to fail to fully react at the end of heating.It is also found that the apparent activation energy and preexponential factor have kinetic compensation effect during the car-bonization of ICHB.
