Research on Improving Dewatering Performance of Diaphragm Filter Press in Wastewater Treatment in Iron and Steel Industry

With the continuous improvement of the production capacity of my country's iron and steel enterprises, the resulting wastewater treatment, recycling and reuse, and compliance discharge have become new environmental governance problems. The discharge of these wastewater into the nature has extremely bad effects on the environment, so the advanced treatment of these industrial wastewater has become one of the key research topics. This paper studies the factors that affect the filtration performance of the membrane filter press, finds out the reasons, formulates countermeasures, and implements corresponding measures to guide daily production, and finally achieves the expected goal of improving the dehydration performance and cycle production capacity of the membrane filter press. The main work is as follows: (1) Study the process flow of solid-liquid separation of the diaphragm filter press, and divide the process into three processes, the initial filter chamber feed, the intermediate pressure filtration, and the late diaphragm extrusion. The analysis of the three different stages Influencing factors, in the end, it is considered that the medium-term pressure filtration stage takes the longest time and is also the stage with the most relevant influencing factors. The subject will mainly focus on the medium-term pressure filtration stage to carry out related research. (2) Use Fluent software to simulate and analyze the filtration speed, filtration time, pressure distribution, solid phase distribution, etc. of the sludge in a single filter chamber, and discuss and study the law of mud cake formation and change, and the flow law of solid-liquid two-phase flow. Simulate and explore the changing law of the moisture content of the filter cake. (3) Analyze and study the factors that affect the productivity and performance of the diaphragm filter press, and find out the factors that can be changed or adjusted in daily production, such as feeding speed, feeding pressure, feeding method, agent adjustment, etc., These four aspects can be adjusted without changing the filter structure. There are two kinds of filters on site with different feeding methods, one is upper feeding and the other is center feeding. Through experiments, it is found that the center feeding is more suitable. Comprehensive consideration of economic factors, change the previous concept that the higher the feed pressure, the better the dewatering performance, and select the best feed pressure; study the combined dosage of Fe Cl3 and hydrated lime (Ca(OH)2) on the specific resistance of sludge Influence and influence on the moisture content and dehydration rate of the final filter cake. (4) The diaphragm filter press and related equipment imported from Italy with the model HB-1500 of the sewage treatment department were selected as the experimental equipment to verify the accuracy of the preliminary simulation experiment. (5) Through experiments, determine the best operating parameters, structure, filter chamber thickness, and pharmaceutical use of the diaphragm filter press, so that the moisture content of the filter cake is further reduced, the production capacity is improved, and the daily production environmental protection requirements are met. It provides valuable experimental data for the design progress of filter press equipment in the future.