氧化铝蒸发系统的模拟

Simulation of Alumina Evaporation System

在氧化铝蒸发工序中,生蒸汽流量和母液出口浓度是重要的能耗指标和出口质量指标;目前,在实际生产中由于采用离线浓度检测,以致对蒸汽流量和出口浓度的控制严重滞后;因此,针对蒸汽流量控制和浓度检测滞后的现状,建立了氧化铝四效蒸发系统的数学模型;采用Newton-Raphson算法求解四效蒸发系统模型,并对实际氧化铝四效蒸发系统进行了模拟计算,进而绘出母液出口浓度和总蒸发水量的误差曲线图;结果表明该模型准确、高效,对蒸发系统节能降耗有现实的指导意义。

The fresh steam flow and the outlet eoneentration are important energy consumption index and outlet quality index in the alumina evaporation process. At present, the off--line method is universally adopted in manufacture so that the control of the fresh steam flow and the outlet concentration severely lags. According to this, the mathematieal model for four-- effect alumina evaporators is established. Newton--Raphson method is used to solve the model of four--effect evaporation system and the practical system has been computed analogically. The error curve diagrams of the outlet eoneentration and the total evaporation have been plotted. The practical simulation indicates that the model is accurate and efficient and it has guidance significance in saving energy and controlling depletion.