Improvement of plate and frame filter press

The main function of plate and frame filter press is to carry out rapid solid-liquid separation of suspended liquid with concentration. It is usually multi-layer stainless steel plate and frame structure, which is used for the liquid concentration of 50%, and the liquid viscosity is relatively low, containing less slag.

Plate and frame filter press can sterilize, purify and filter liquid. With the continuous improvement of the output of power plants, the production of sludge wastewater substances is also increasing. For the substances that cannot be effectively treated, only by removing and discharging them will lead to environmental pollution and energy waste to a large extent.

The plate and frame filter press takes the pneumatic diaphragm pump as the supply pump, and then presses the mud into the filter press to help it filter, and finally realizes the separation of solid liquid, which can greatly improve the sludge utilization efficiency of the converter.

In recent years, the frame-frame filter press of our country has made some progress in theory and actually, but compared with foreign countries, there is still a large gap, so the research and optimization of the frame-frame filter press is very necessary.

With the development of urbanization, the total discharge of sludge and sewage is greatly increased. A variety of toxic substances in sewage sludge will not only cause the pollution of land resources and water resources, but also cause very serious harm to human body. China's water resources are already in a very short situation, and the pollution of water resources is very serious. Since the 1990s, people's awareness of environmental protection has been improved to a certain extent, and sewage treatment in most cities in China has been developing rapidly. Of the more than 660 cities in China, 380 have 790 wastewater treatment plants. When sewage treatment is carried out in sewage treatment plants, 10 million tons of sludge will be produced every day, with a water content of about 79%. There are a lot of bacteria and harmful substances in these sludge, and they become solid waste substances in the sewage treatment process. If the sludge can not be treated reasonably, it will cause serious environmental pollution. Filtration is a traditional solid-liquid separation technology, which has a certain degree of application in chemical industry, environmental protection, medical and other fields, but also plays a very important role in sludge dewatering technology. The most commonly used method in the world is mechanical dehydration. In essence, this method is filtered by filter cake, usually called surface filtration. Filter cake is a common machine used in the process of sludge dewatering. The filter cloth can filter out the suspended particles with a diameter greater than 1um, and it can treat the sludge with suspended particles content above 1%. In the industry of filtration and separation, the filter press is in a key position. The effective combination of filtration, pretreatment and filtration functions enables the filter press to filter ultra-fine particles. The plate and frame filter press is a kind of filtration machinery and equipment for solid-liquid separation that is often used. It has become a product with a large amount of supply demand in the industrial environment. Therefore, it is of very important practical significance to improve the degree of automation, reduce the manual workload, and better meet the actual needs of the site.

2. Current situation and development trend of plate and frame filter press

2.1 Introduction of plate and frame filter press The most critical part of plate and frame filter press is the filter plate and filter frame. The two are arranged and combined to slide on both sides of the bracket. The system can use the pressing device to press the filter frame and filter plate, and finally carry out further sealing and filtering operation on the sludge. The main function of the filter plate is washing plate and not washing plate two kinds, in the filter box and filter plate four corners of the hole, then can be connected to the space in the box for compression, can let the bottom hole and the left and right sides of the board are connected to each other, the upper left hole and the two sides of the board are also connected to each other, can let the washing liquid into, The small hole in the lower right corner is also connected with both sides of the board, which can discharge the washing liquid.

2.2 Development Trend of plate-frame filter press  was originally invented in Europe and plays an important role in chemical, medical, coal and other filtration processes. With the bad phenomena of technology drastically reduced. In addition, by improving the hopper of the bucket lifting machine, the wear resistance of the hopper is enhanced, the service performance of the hopper is significantly improved, and the production efficiency is greatly improved. Continuous development, plate and frame filter press, has a more important role. At present, there are many powerful professional companies on the market, for the production of plate and frame filter press, and the products are more and more professional, can meet the needs of different customers, and its sewage treatment capacity and reliable performance has been significantly increased. For example, the APN18 plate frame filter press produced by a Spanish company is a connecting rod structure. Through this structure, the overall diameter of the pressing cylinder can be reduced and the size of the pressing force of the filter plate can be guaranteed. Compared with foreign mature products, the product design level of domestic filter press is relatively low, and the performance and reliability are not as good as foreign products. After analyzing the market, we can know that the domestic market demand for plate and frame filter press is very huge, and the product is in the period of renewal, its profit is very rich. There are also many companies to research and develop independent intellectual property rights of high-performance products, which has led to a lot of competitive companies, but also led to a lot of universities, as well as school-enterprise cooperation to carry out the research and development of plate and frame filter press.

3 The improved plate frame filter press of the shaft end sealing device of the reducer used in the ball mill plays a very important role in the wastewater treatment system. Its structure is simple, easy to operate, and stable operation, maintenance is also very convenient. And for the size of the filter area, the optional range is very flexible, covers a small area, good adaptability to the material. These characteristics make the filter press is widely used in the desulfurization wastewater discharge and treatment system. However, for the filter press, the surrounding environmental problems have not been well solved. For example, after the new skeleton oil seal is replaced by the reducer of the ball mill, serious oil leakage begins in the place of the oil seal after running for a period of time, which will eventually lead to serious pollution of the equipment ground health and the loss of lubricating oil. For example, when changing the skeleton oil seal, the reducer should be disassembled and replaced. The workload of inspection and repair is huge, and it is also very dangerous.

3.1 Technical Background The utility model relates to a shaft end sealing device of a reducer for a ball mill. The ball mill is a key equipment for further crushing after crushing the material. This equipment is widely used in cement, fire resistant materials, chemical fertilizers, glass ceramics and non-ferrous metal beneficiation, new materials construction, silicate products and other production industries, on a variety of ores and a variety of abrasive materials for wet grinding and dry grinding. The ball mill is generally divided into wet and dry grinding methods. For the wet ball mill, when working, it is necessary to convert the high speed gear of the reducer into the gear suitable for the work of the ball mill. The ball mill has the characteristics of simple operation, small investment capital and small maintenance. For wet ball mill reducer lubrication and sealing mode, it uses the axial oil seal sealing mode, the advantages of this way is relatively simple structure, relatively low cost, and convenient replacement. However, this sealing structure is easy to lead to certain friction on the spindle, leading to serious wear of the spindle, and finally lead to the shaft end sealing effect of the reducer shaft is not good, and after the spindle wear, the replacement cost is very high, and for the spindle, the procurement cycle is very long, may lead to serious leakage, and finally affect the working effect and life of the wet ball mill.

3.2 Specific implementation methods The design purpose of this technology is to improve the above technical problems, the design and completion of a reducer shaft end sealing device about the ball mill, the design structure of the device is reasonable, the use of a double-layer sealing structure. If the inner sealing structure is worn, leading to damage at the contact point of the spindle, then the outer sealing structure is installed to further achieve a tight seal of the shaft end of the reducer, so as to increase the total service time of the reducer. The technical solution can solve the above problem. The technology provides a reducer shaft end sealing device for ball mill, which comprises a fixed flange and a sealing sleeve. The sealing sleeve is constituted by a sealing ring and a wedge sealing ring, and the seal ring is placed inside the wedge sealing ring, and the wedge sealing ring is closely connected with the spindle. The wedge-shaped sealing ring is closely matched with the wedge-shaped surface of the upper part of the fixed flange, and the inner fastening bolt is fixed on the reducer; The shaft end sealing device of the reducer also includes an outer flange, and a wedge sealing ring on the wedge surface of the outer flange, which is fixed on the reducer through the outer fastening bolt. The shaft end sealing device of the reducer used in the ball mill is one of the important parts of the plate frame filter press, which makes the oil leakage situation of the ball mill significantly improved, also significantly extended the working time of the reducer, and reduced the overhaul workload.

For the press cloth, press plate and mud storage bucket, they shoulder the functions of filtering water, squeezing and mud storage. In the process of equipment operation, the press cloth will produce folds and press plate fracture, which will lead to waste water and sludge splashing onto the wall of the factory through the gap between the press plate and the press cloth, causing serious pollution to the surrounding environment. The mud storage bucket is the core component of the plate and frame filter press. The function of the mud storage bucket is to save the filter cake after the dry water filtration. After the storage is full, it is transported to the stacking place by truck. However, sometimes the forming degree of filter cake is relatively poor, so that when unloading filter cake, the filter cake will be scattered under the bucket, and then lead to the pollution of the surrounding environment. In this case, the method of installing mud curtain can be adopted, which can effectively reduce the environmental pollution.

4.1 Technical background The filter press is generally composed of pressing, filtering mechanism and frame. During the operation of the equipment, the sludge is transported to the press cloth and press cloth, and then the hydraulic system is used to further press the frame, and finally the water through the filter cloth into the trench. The sludge is pressed into cake and kept in the mud storage bucket, and finally transported and unloaded. In this process, the press cloth will fold and age, which may lead to sludge leakage and sputtering, which will have an impact on the environment.

4.2 Specific implementation methods Add a whole circle of PVC soft strips around the frame of plate and frame filter press, which can resist corrosion and erosion. For example, it can effectively isolate the sludge leakage caused by the fold of the press cloth and prevent direct sunlight from shining on the press cloth, which greatly improves the service life of the press cloth. Make use of PVC transparent soft plate to make two mud curtain placed on the left and right sides of the discharge hopper of the filter press, and then design two hand on the factory wall, the use of steel wire rope and universal wheel to pull up and down the soft plate, can be used to prevent the mud cake pollution to the wall, and only need to clean the fender regularly. After the mud cake loading is completed, the mud curtain can be raised to make the overall environment of the waste water building in the factory cleaner. After the transformation, the wall around the plate and frame filter press is very clean and tidy, and there is no need to wash and paint the wall often.

5. The optimization of the anti-mud process of the plate and frame filter press in the wastewater system of the plate and frame filter press, as well as the optimization of the shaft end sealing device of the reducer used in the ball mill, has played a good environmental protection effect and can save a lot of manpower, material resources and financial resources.