Installation and commissioning of quick-opening diaphragm filter presses

sports event

Coal processing plant is the first large-scale coking coal processing plant designed and built by China itself, and the annual processing capacity has reached 5.76Mr. Coal processing plant washes raw coal from a dozen mines such as No.2 mine, No.4 mine, No.5 mine, No.10 mine, No.11 mine, No.12 mine, No.13 mine, Pingyu mine, Shushan mine, Dazhuang mine, Gaoshuang mine, etc. Raw coal is sourced from a wide range of sources and the quality of the coal varies a lot. Raw coal comes from a wide range of sources and the quality of coal varies greatly. The continuous deterioration of the quality of the washed coal, coupled with the gradual increase in the user's requirements for product quality, has made many of the original process, equipment has been insufficient to meet the current production requirements. Especially in the dewatering process of flotation concentrate, when encountering muddy coal and friable coal, it is difficult for the filter to form cakes with high moisture, which not only causes the loss of concentrate by bubbling material in the concentrate pool, but also makes the total moisture of concentrate high and affects the quality of the products. Moreover, our plant is undergoing technological transformation and upgrading, and then the processing capacity will be jumped to the level of ten million tonnes, and the amount of flotation will be increased exponentially, which makes the pressure of the dewatering process of flotation concentrate even more self-evident. Therefore, the launching of new and efficient flotation coal dewatering equipment is an inevitable choice for our plant to expand production and increase capacity.

diaphragm filter press

diaphragm filter pressAdopting machine, electricity and liquid integration manufacturing, high technology content, stable and reliable performance. It adopts PLC and human-machine interface control, and the working process is divided into seven processes: pressing the filter plate, feeding filtration, blowing back, diaphragm pressing, blowing air release, loosening the filter plate, and pulling the plate to unload the material, with fast filtration speed and high degree of automation. The filter press adopts reinforced polypropylene filter plate with high strength, and after the diaphragm inflatable press, the moisture of the filter cake is further reduced in a shorter time, and the efficiency is greatly improved.

Installation of filter presses

1) Lifting the whole set When lifting the set, unload the hydraulic station first. If the set is large, all the movable filter plates can be unloaded to reduce the lifting weight. Be careful not to damage the surface of the filter plates, and put the filter plates back in the original order after the set is installed (the diaphragm plate and the ordinary filter plate should be placed between each other). The wire ropes used for lifting should be hooked to the lifting holes at both ends of the main beam. When lifting, the centre of gravity must be found, the wire rope must be reasonably selected, and the parts of the wire rope in contact with the equipment must be lined with cloth or other soft materials.

2)filter pressInstallation In general, the filter press should be installed horizontally on the concrete base structure frame, the thrust plate feet are fixed with M20x300 anchor bolts, and the cylinder seat feet are not fixed (for some models where the cylinder seat and its feet are separated, the feet should be fixed, but the connecting bolts between the cylinder seat and the feet have to be removed) in order to ensure that there is a certain axial displacement of the main beam in the stress condition. The foundation should be made of cement secondary grouting, the plane of the foundation should be smooth, the elevation should be based on the convenience of slag unloading operation, and the opening of the underwater gutter of the plant should be considered. When installing the machine, the frame should be levelled and diagonally corrected. The closer the installation place is to the material handling site, the better, and in order to facilitate the operation of unloading, leave a space of one metre or so around the frame. The base of the whole machine should be higher than the foundation surface by a certain size, so that the liquid catching device can be placed under the machine. The electrical control box should be installed in the operation room isolated from corrosive gases to avoid damage to the electrical components, which may affect the normal operation. The order of the filter plates should be based on the order of the filter plates at the time of discharge, and should not be reversed arbitrarily. In particular, the wall plate at the end of the compression plate should not be moved to other positions. The filter cloth should only be ironed with a special tool such as a soldering iron to avoid burring of the filter cloth. The pressure and flow rate of the feed pump should be matched with the product, and the return pipe and pressure gauge should be installed on the feed pipe to ensure the pressure adjustment. Hydraulic station installation location can be determined according to the actual site, installation, should avoid other coal, water and other debris mixed into the tank, affecting the sensitivity of the action of the hydraulic components, or even damage to the hydraulic components.

3) Installation of piping system The installation of piping can be installed according to the piping layout provided by the factory and combined with the actual situation on the site of the user unit, but it should be noted that the installation, use and maintenance of the pipeline must be convenient, the pipeline should not be connected to the wrong pipeline, the pipeline should be as short as possible. Figure 2 shows the pipeline installation layout of our factory. The pipeline initially designed by our plant also had a lot of problems during the commissioning period. For example, at first, the blowback material returned directly to the slurry drum, and the filter press could not be processed directly back to the flotation concentrate pool, but due to the high pressure of the blowback, and to the concentrate pool of the return pipe is thin, resulting in the slurry drum hold open, a large amount of bubbling material and affect the operation of equipment, so it was changed to the existing piping arrangement; and filtrate discharge was initially designed as a single-end double-slot pooling, single-end discharge, due to the fast filtration speed of the filter press, the filtrate discharge is not as good as, resulting in a run-up situation from time to time, the filtrate discharge is not as good as. Due to the fast filtration speed of the filter press, the filtrate is not discharged as quickly as it should be, which leads to the running situation from time to time. In addition, this machine can be equipped with an air compressor and an air storage tank for air blowing as required. Corresponding equipment and various valves can be selected according to process requirements. The selection of feed pump can be made according to the requirements of flow rate, granularity and viscosity, but the pressure should not exceed the maximum filtration pressure of the equipment.

Commissioning of filter presses

1) Wipe the hydraulic station and electric control box clean, clean the inside of the oil tank, check the power supply and the pressure tightness, whether the return oil pipe is installed correctly, whether the upper and lower pressure limits of the electric contact pressure gauge (DY) are set appropriately, whether the power supply wiring is safe and reasonable.

2) Clean the frame, filter plate and piston rod, check whether the filter plate is neatly and correctly arranged; check whether there is any folding phenomenon in the installation of the filter cloth, if so, it needs to be spread out. Normal phenomenon . 3) Check whether the configuration of pipes and valves for feeding, washing, blowing (including positive and negative blowing system), liquid discharge and pressing is correct and reasonable.

Electricity Hydraulics Commissioning

1) When the above required inspection items to confirm that there is no error, to the oil tank filled with clean hydraulic oil to the specified oil level, turn on the power supply, click the "return" button, observe whether the motor is along the clockwise direction of the positive rotation. Then, loosen the high-pressure relief valve in the counterclockwise direction, press the "pressure" button, adjust the high-pressure relief valve to about 2MPa, and then make the piston move several times to exhaust the air in the cylinder.

2) When pressing for the first time, adjust the pressure to IOMPa, and after pressing, observe whether the connections of the frame are normal and whether the beam is deformed. If everything is normal, then adjust the pressure to 15MPa, 20MPa, 25MPa respectively, and observe once for each adjustment. If there is any abnormality, press the emergency stop button and return to unload the pressure. After identifying the cause, re-commissioning.

3) Let the piston rod drive the pressure plate back and forth three times to see whether the oil pressure rises to the upper limit of the electric contact ￡f force table will automatically stop. In the pressure state, observe the oil pressure drop, in the first pressure, the pressure drop rate ≤ 3MPa / l0min is normal, when the pressure drops to the lower limit of the electric contact pressure gauge, the motor automatically starts on the pressure, the second pressure drop rate ~ < 2MPa / 2Omin is normal.

Filter section debugging

1)Press the filter plate firmly and keep pressure .

2) Open all the liquid outlet valves, feed the pump on the amount of gate open about one-quarter of the feed pump, start the feed pump, observe the filtrate and feed pressure changes, such as pressure is too high, you need to open the valve on the return line to adjust. Due to the capillary effect of the filter cloth, the filtrate is slightly turbid at the beginning of filtration.

Status of equipment production

As this filter press was firstly used in the dewatering of flotation concentrate, some parts and equipments were not well adapted to the characteristics of low concentration of flotation concentrate and easy to settle, so there were many equipment and process problems. Through the communication with the manufacturer and the joint efforts of our technicians and workers, we overcame and solved many problems and ensured that the filter press could be used for the first time in the flotation concentrate dewatering process.Fine Coal Filter PressThe three filter presses were put into operation in August 2011, and all the components were running well with good stability and low accident rate, and the maintenance was convenient. The three filter presses were formally put into operation in August 2011, and all the components are running well, with good stability, low accident rate, convenient maintenance, and reduced labour intensity of the workers; it can reach about 4 cycles per hour, and the cake moisture is controlled near 21%-24%, which has reached the expected process performance indexes, and has achieved practical economic benefits.

concluding remarks

Quick-opening diaphragm filter pressThe use of the fast-opening diaphragm filter press not only reduces the moisture content of the coal, but also reduces the amount of high ash and fine mud in the system. The visualised operation and high degree of automation have reduced the working intensity and improved the working environment of the workers; the use of fast-opening diaphragm filter press not only reduces the moisture content of the refined coal, but also reduces the accumulation of high ash and fine sludge in the system, which in turn improves the refined coal yield and quality, and achieves better economic and social benefits.