基于机理模型的永川污水处理厂运行诊断与碳源优化

对重庆永川污水处理厂为期1.5年的历史数据和补充实验数据进行采集与分析,确定了其进水水质特征、运行方式、生化反应状态,对其全年平均状态及历时波动状态均完成了以机理模型为核心的数字化模拟仿真,确定了该污水处理厂现有运行状态中存在的问题与风险。通过运行参数的调整,可有效规避二沉池过负荷、系统污泥分布不均等风险;以合理的污泥龄运行,利用污水处理厂的进水水质特征,在出水水质稳定达标的前提下,减少外加碳源与药剂的投加。在平均状态、极端条件、历时波动等情景下进行了碳源投加的定量评估,动态进水状态下定量评估结果显示:一期甲醇年平均投加量可减少为原投加量的80%,二期可减少为原投加量的60%。

OPERATION DIAGNOSIS AND CARBON SOURCE OPTIMIZATION OF YONGCHUAN WASTEWATER TREATMENT PLANT USING PROCESS MODELING

The whole plant models were set up for Phase Ⅰ and Phase Ⅱ processes at Yongchuan wastewater treatment plant (WWTP) to evaluate the operation conditions and to determine the potential optimization strategies.The historical data for 1.5 years and supplementary experimental data of Chongqing Yongchuan sewage treatment plant were collected,analyzed and used for the model calibration.And its influent water quality characteristics,operation mode and biochemical reaction state were determined.The digital simulation based on the mechanism model was completed for its annual average state and duration fluctuation state.The historical and current operation conditions of the WWTP was assessed for the potential problems and risks.The optimization strategies including operation improvement and external carbon reduction were determined using the calibrated models.Through the adjustment of operation parameters,the risk of overload of secondary sedimentation tank and uneven distribution of sludge in the system could be effectively avoided with operating at a reasonable sludge age and using inlet water quality characteristics,it could reduce the addition of additional carbon source and reagent on the premise that the effluent quality was stable and up to standard.The quantitative evaluation of the external carbon addition was carried out under average,extreme,and dynamic conditions,respectively.As the result of dynamic simulation analysis:with the improvement on operation parameters such as recycle flow and sludge wastage,the annual average methanol addition can be reduced to 80% for Phase Ⅰ and 60% for Phase Ⅱ,respectively,as compared to the actual dosage at WWTP.