针对石灰石-石膏湿法烟气脱硫系统（wet flue gas desulfurization, WFGD）工作过程中浆液pH难以精准测量、不利于WFGD作业的问题，建立一种基于双向门控循环单元的脱硫系统pH预测模型。首先，对原始数据进行清洗和归一化处理；其次，基于最大信息系数分析得出13个特征值为输入变量，pH为输出变量，并建立浆液pH模型；最后，运行模型，并对结果进行评价。研究结果显示，与长短期记忆和门控循环相比，所选用的数学模型的平均绝对误差分别下降了11.95%、24.92%，均方根误差分别下降了10.64%、19.49%，决定系数分别提高了1.79%、3.08%。表明基于双向门控循环单元的pH预测模型具有较高的精确度和稳定性，具有工程应用价值，为现有脱硫塔pH预测模型提供了工程参考。

Aiming to address the issue of accurately measuring the slurry pH value during the operation of limestone-gypsum wet flue gas desulfurization (WFGD) system, which hinders the efficient operation of WFGD, a prediction model for FGD system pH based on bi-directional gated recirculation unit(BiGRU) has been developed. Firstly, the raw data were cleaned and normalized. Secondly, based on the maximum information coefficient analysis, 13 characteristic values were obtained as input variables and pH as output variables, and a slurry pH model was established. Finally, the model was run and the results were evaluated. Compared to LSTM and GRU, the results indicate that the mean absolute error of this mathematical model decreases by 11.95% and 24.92%, while the root mean square error decreases by 10.64% and 19.49%. Additionally, the coefficient of determination improves by 1.79% and 3.08% respectively. This demonstrates that the BiGRU-based pH predictive model exhibits high accuracy and stability, making it valuable for engineering applications and providing an important reference for predicting pH models in existing desulfurization tower systems.