轻烧氧化镁气流床煅烧炉热工过程及煅烧风量研究

轻烧氧化镁气流床煅烧炉热工行为研究是其热工参数优化、实现节能降耗的必需的基础性工作之一。基于Euler-Lagrange理论建立了某企业轻烧氧化镁气流床煅烧炉数值计算模型,籍此研究了炉内气固流动、传热及分解过程基本规律,并确定了现有产量下的适宜煅烧风量。结果表明：主炉内煅烧烟气旋流上升,温度中心高、壁面低;副炉内旋流效应骤减,温度趋于均匀;距离烟气入口4~18 m行程范围内,气固换热剧烈,物料快速分解,分解率达96%,而后于24 m处分解完全。将煅烧风量降至原有风量的91.22%、气料体积质量比降至1.46 Nm³/kg,不但提高了炉窑空间利用率,同时吨产品燃耗降低了8.78%。

Study on the thermal process and calcination gas flow rate of light-burned magnesia entrained-flow calciner

Research on the thermal behavior of light-burned magnesia entrained-flow calciner is one of the necessary basic works for optimizing thermal parameters and achieving energy saving and consumption reduction.Based on Euler-Lagrange theory,a numerical model of a company′s light-burned magnesia entrained-flow calciner was established.The basic laws of gas-solid flow,heat transfer and decomposition process in the calciner were studied,and the suitable calcination gas flow rate under the current production was determined.The results showed that the calcination flue gas in the main calciner rose in a swirling flow,and the center temperature was high as well as the wall was low.The swirling effect in the sub-calciner decreased sharply and the temperature tended to be uniform.Within the range of 4~18 m from the flue gas inlet,the gas-solid heat ex-change was intense and the materials were quickly decomposed up to 96%.Then the materials were completely decomposed at 24 m.The calcination gas flow rate was reduced to 91.22% of the original and the gas-to-material ratio was reduced to 1.46 Nm³/kg,which improved the space utilization rate of the calciner,and the fuel consumption per ton of product was reduced by 8.78%.