高炉水冲渣过程中硫化物排放计算分析

Calculation and Analysis of Sulfide Element Discharged During BF Slag Granulation

高炉炉料中的硫元素约85%随炉渣排出,对高炉水冲渣过程中的硫化物排放进行了计算分析。计算结果表明:①炉渣与水接触的0.3s内产生大量的H_(2)S和SO_(2),在随蒸汽及气溶胶外排至大气的过程中,有部分H_(2)S转化成SO_(2),温度较低时会生成H_(2)SO_(4);②当人炉硫负荷为4kg/t时,冲渣点烟窗处的硫化物排放如全部折算成SO_(2)为369.96mg/m^(3),如全部折算成H_(2)S为196.54mg/m^(3);③从某1500m^(3)高炉渣处理系统的实测结果来看,硫化物排放峰值高于理论计算值;④有部分H_(2)S和SO_(2)与Ca(OH)2反应生成CaSO_(4)·0.5H_(2)O和CaSO_(4)·2H_(2)O,并在循环过程中结晶析出,是造成滤层板结及管道堵塞的根本原因。

About 85%of the sulfur element in the BF charge is discharged along with the slag.The sulfide element dis-charged during slag granulation is calculated and analyzed.The results show that:(1)a large amount of H,S and SO,mass is generated within O.3s after the slag contacts water,and part of the H,S mass is converted into SO,mass when they are e-mitted to the atmosphere with steam and aerosols,and H_(2)SO_(4) mass will be formed when the temperature is low;(2)as the load of sulfur charged to the furnace is 4kg/t,the sulfide emitted from the chimney of the slag granulation system is 369.96 mg/m*if all of sulfur is converted into SO_(2),and 196.54mg/m if all converted into H_(2)S;(3)according to the test results of a slag treatment system for a 1500m^(3) BF,the measured peak sulfide emission is higher than the calculated one;(4)part of H,S and SO_(2) masses react with Ca(OH)2,forming CaSO_(4)·0.5H_(2)O and CaSO_(4)·2H_(2)O masses,which will crystallize and will be precipitated during the circulation;they are the root causes of filter layer caking and pipeline blockage.