PTA装置醋酸脱水塔的动态模拟及控制策略分析

以PTA装置醋酸脱水塔为研究对象，在该醋酸脱水塔的稳态模型的基础上，通过建立的平衡级动态数学模型以及补充设置好的动态参数，利用Aspen Plus软件建立好动态模型。以Aspen Dynamics软件为工具，用回流流量控制灵敏板温度，塔釜再沸器热负荷与进料流量F ₁呈比例控制，模拟设计出了控制策略CS1。又为了保证在进料流量扰动时塔底醋酸浓度更加稳定，利用塔釜再沸器热负荷来控制塔釜醋酸浓度，设计出了控制策略CS2。将两种不同的控制策略对其动态响应进行分析比较，得出在相同目标条件下表现更优的控制策略，为实际生产和控制方案的设计提供方向和指导。

Dynamic simulation and analysis of control strategies of acetic acid dehydration tower in PTA plant

The research object of this paper is acetic acid dehydration tower in PTA plant. The dynamic model was based on the dynamic mathematical model of the balance level and supplemented with the set dynamic parameters and the steady state model which was derived by using Aspen Plus. Next, the temperature of the sensitive stage was controlled by the reflux flow, and the column kettle reboiler duty was proportional to the feed flow F ₁. Aspen Dynamics was used to simulate the control strategy CS1, which has the dynamic response analysis of the key index parameters in the acetic acid dehydration tower after disturbance of the feed flow. To ensure the concentration of acetic acid at the bottom of the tower is more stable when the feed flow is disturbed, the heat load of the bottom tank reboiler is used to control the acetic acid concentration in the tower, and the control strategy CS2 is designed. Two kinds of different control strategies were analyzed and compared to their dynamic responses to obtain better control strategies under the same target conditions, which provided direction and guidance for the actual production and control strategy design.