废气分析在RH脱碳过程中的应用

根据RH废气分析系统对废气流量及其中CO、CO2气体含量的测量,建立了废气分析脱碳数学模型。经验证,模型计算值与实际测量值吻合较好。对于成品碳的质量分数小于等于20×10-6的超低碳钢,模型计算的RH自然脱碳终点碳的质量分数误差在±3×10-6之间。废气流量修正系数δ采用分段取值更能符合实际情况,RH精炼开始3 min内,δ为0.35,3 min后δ为0.6。在RH自然脱碳后期,当废气中CO的质量分数由峰值降低到5%时,钢水中碳的质量分数的平均值达到13×10-6,已经低于RH终点碳含量的要求值,可以判定RH脱碳过程结束。

Application of Waste Gas Analysis for RH Decarburization Process

Based on the waste gas flow rate and CO, CO_2 content measured by the RH waste gas analysis system, the mathematic model on waste gas analysis decarburization was established. The calculated results by model inoscu-lated the measured ones. The precision of the end-point carbon content of conventional RH treatment was ± 3 × 10~(-6) for ULC steel(ω_(C])≤20 ×10~(-6)). The correction coefficient,δ, of waste gas flow rate was evaluated by two subsections according with the factual production process. The value of δ was 0.35 when the RH treatment time was less than 3 min, otherwise δ was 0.6. When the CO content of waste gas decreased to 5 % from the maximum at the terminal stage of RH decarburization, the average value of carbon content in the bulk liquid steel was 13 ×10~(-6) which was below the requirement content at the end of RH process, therefore, the RH decarburization process could be judged to finish.