- 期刊
高爐內爐渣流動性與焦炭熱間強度之關鍵指標建立及其應用
Development and Application of Final Slag Fluidity Index and Coke Strength After Reaction Index for Blast Furnace Operation
摘要
高爐產製鐵水之績效端視爐上部透氣性與爐下部透液性而定，而爐料品質優劣有顯著的影響，尤其焦炭。當焦炭強度差時，爐內粒度變小，粉料增加，造成爐內透氣性變差、熔渣滴下不易、爐床出渣出鐵不順等異常爐況，進而造成鐵水產量損失與高爐壽命減少。故高爐亟需發展爐渣流動性與適當的焦炭熱間強度(Coke Strength after Reaction, CSR)等指標，來協助操作人員提早因應爐況變化。爐渣流動性指標（指渣之液化溫度及黏度）建立乃以高爐渣為基礎，添加不同比率的MgO、Al_2O_3及控制B_2(CaO/SiO_2)等所做出的半合成渣，探討對此熔渣流動性之影響，依此建立了高爐渣流動性線上指標及斷渣預警系統，已全面應用於中鋼集團之高爐，即時提供爐操人員掌握爐渣波動，並作出因應對策，為一種判斷爐床通液性好壞之關鍵指標。其所衍生之改善方案亦常應用於檢討原料配比之補救措施，如渣中Al_2O_3偏高影響爐渣流動性之調整方案。另外，適當的焦炭熱間強度指標之建立乃透過高爐鼓風嘴焦炭的取樣，進行焦炭性質試驗，如I型轉鼓強度及磨耗率之分析，探討鼓風嘴焦炭性質與高爐操作條件和透氣阻力指標之優劣關係，建立了包含噴煤率與爐渣液化溫度等爐操條件下，適當入爐焦炭CSR之指標及其線上系統，有助於高爐調整焦炭或爐操之參考。
並列摘要
The performance of hot metal (HM) produced from Blast furnace (BF) was determined by gaspermeability in the upper portion of BF and liquidpermeability in the lower part of BF. It was wellknown that burden quality has a significant impact on the BF permeability. When the coke strength is weak, the coke fines inside BF become finer that reduce production and BF life. It is necessary to develop a Final Slag Fluidity Index and a Coke Strength after Reaction (CSR) Index for a Blast Furnace. In this study, the SiO_2-Al_2O_3-CaO-MgO-TiO_2 semi-synthetic slag was prepared based on BF slag. We investigated related factors (MgO, Al_2O_3, CaO/SiO_2) of slag fluidity (liquid temperature and viscosity) and its application. We installed slagflow- off warning system in the process computer of all CSC BFs to present slag fluidity in real time. This system immediately provided BF staffs process information to control the variation of slag fluidity to ensure effective and smooth BF operation. The improvement strategies derived from the indices were often used as a remedy in reviewing burden ratio. The required CSR index of BFs and the online system were established by using the sampling coke properties at different gas permeability resistance and pulverized coal injection ratio to provide references for HM and coke production.