【摘要】 以碳酸钙为固氟添加剂,以炉渣及粉煤灰等低氟材料取代全部或部分粘土作为粘结剂来制作蜂窝煤,进行了燃煤降氟的试验研究。结果表明,添加碳酸钙能有效降低蜂窝煤燃烧时候的氟排放,当煤∶粘土∶CaCO3的质量比为70∶17∶13时,碳酸钙的固氟效果最佳,氟的排放率可降低64.1%。以炉渣为粘结剂制作蜂窝煤能够显著降低燃烧时向外界排放的氟化物量,当煤∶炉渣∶CaCO3为80∶8∶12时,蜂窝煤燃烧排氟量较小且趋于稳定。已拌有一定剂量粉煤灰粘结剂的煤中添加15%的粘土后碳酸钙的固氟效果明显改善,当煤∶粘土∶粉煤灰∶CaCO3为70∶15∶9∶6时固氟效果最佳,此时蜂窝煤氟逸出率仅为18.2%,氟的减排率达到77.9%,显著优于未添加粘土时碳酸钙的固氟效果,蜂窝煤添加碳酸钙固氟剂进行高效固氟时,需同时适当增加粉煤灰加入量,以稳定固氟剂的高温固氟效果。更多还原

【Abstract】 Slag and fly ash were selected as composition for the preparation of honeycomb briquette,CaCO3 was used for calcium-based sorbent,the characteristics of fluoride emission from those honeycomb briquettes combustion were obtained successfully.The experimental results indicated that fluoride pollution from honeycomb briquette combustion was effectively reduced by blending with CaCO3,the optimum condition for fluoride retention was coal∶clay∶CaCO3 = 70∶17∶13,and then the fluoride mitigation rate was 64.1%.It was found that coal mixed with slag for honeycomb briquette combustion could reduce fluoride emission remarkably,when coal∶slag∶CaCO3 = 80∶8∶12,fluoride emission rate tended to be stabile and in lowest.Compared with honeycomb briquette composed of coal,fly ash and CaCO3,adding with 15% clay could improve the fluoride removal efficiency of CaCO3 farther,when coal∶clay∶fly ash∶CaCO3 = 70∶15∶9∶6,it reached the optimum efficiency of fluoride retention,and then fluoride emission rate of honeycomb briquette was only 18.2%,the mitigation rate was 77.9%,markedly excelled the result with no clay.So selecting CaCO3 as calcium-based sorbent should increase the dosage of fly ash at the same time,which could consolidate the efficiency of CaCO3 on fluoride retention.更多还原