Diaphragm plate and frame filter press has the characteristics of good stability and strong water resistance in the construction project of deep dehydration of river and lake sediment. In order to improve the integration of equipment control and automatically control the production process, an automatic control system for plate and frame dehydration process parameters is proposed in this paper. The system is an important part of the intelligent management and control system for river and lake sediment dehydration and drying. By analyzing and optimizing the construction parameters of plate and frame pressure filtration of river and lake sediment, this paper defines the time of the expected dry basis of mud feed. For the abnormal construction parameters encountered in the actual production, through the real-time analysis of feed pressure and water output, a targeted improvement scheme is proposed, which significantly improves the production efficiency.
With the rapid development of industry and agriculture and the process of urbanization, the river and lake sediment composed of clay, silt and minerals produces flocculent or honeycomb structural substances formed by sedimentation with the slow flow of water in lakes or rivers (Zhu 2018). Its engineering composition is complex, diverse and contains a certain amount of pollutants. The mechanical dewatering method is applicable to the dewatering treatment of river and lake sediment, which has the characteristics of reducing the quality and volume of sludge, high dewatering rate and low water content of mud cake (Xu, 2016). According to different types of machinery, mechanical dewatering methods mainly include centrifugal separation dewatering method, belt filter press, plate and frame filter press dewatering method, etc. (Zhang, 1981).
The plate and frame filter press dehydrator has been gradually applied to many industries. The research shows that (Chen 2019). The application of diaphragm plate and frame filter press in sludge treatment system and sludge deep dehydration has a water content of less than 40% and a capacity reduction of more than 60%. Many domestic scholars have carried out research on the process parameter optimization of plate and frame filter press. Zhao Yan et al. (Zhao 2013) explored the effects of filter cloth type, sludge feeding time, reagent dosage, feed pressure and purging on high-efficiency dehydration based on the test and analysis of sludge system of catalyst sewage unit, which provided reliable technical parameters for the transformation of pretreatment system of the unit. Ren Wentao et al. (Ren, 2012) solved the important problem of solid-liquid separation of coal slurry water by adding plate and frame pressure filtration link on the basis of GPJ-120 pressure filter. The filtrate after secondary treatment can be directly used as circulating water. Jia Teng (Jia, 2018) improved and optimized the PLC control program of bamzbl120 plate and frame filter press commonly used in concentrator, and realized a series of functions such as automatic plate pulling, pressing plate, filtration, pressure maintaining, etc. At the same time, the structure and feeding mode of plate and frame filter press are optimized, which greatly improves the operation stability and dehydration effect of the equipment. Throughout all similar reports, the research on the optimization of process parameters of plate and frame filter press is mainly applied to sewage and slime water. There is no relevant research on the optimization of process parameters of supporting control systems related to large-scale river and lake bottom mud plate and frame filter press dehydration treatment.
