liquid ring vacuum pump of  vacuum dewatering 

Vacuum dewatering is widely used in dewatering of pulverized coal, mineral powder, pulp, alkali, dyes, rubber and cement. Coal Washery in coal industry uses liquid ring vacuum pump and filter to suck water in the slurry water, so as to get dry slurry (filter cake), which is the most typical and widespread example in the application of liquid ring vacuum dewatering. Vacuum dewatering in paper mills is also a typical case of vacuum dewatering. Its main principle is vacuum dewatering of pulp by liquid ring vacuum pump.

2BE1 Series Liquid Ring Vacuum Pump

Before dehydration, open the cover of the water tank of the liquid ring vacuum pump unit and inject clean water into the vacuum chamber and catchment chamber to make the water surface level or slightly higher than the nozzle of the tank, adjust the buckle tightly, cover the lid tightly, block the water intake with 3-4 mm thick rubber plate, check the vacuum degree of the empty load of the pump, and the pump table should be greater than 650-700 mm Hg. In addition, it is necessary to check the availability of binders and repair supplies as well as commonly used repair tools.

Opening ring vacuum pump suction, generally control vacuum table 1 minute gradually extended to 400 ~ 500 mmHg, the highest value should not be greater than 650 ~ 700 mmHg. If the required vacuum can not be met within the specified time (3 minutes), the leak should be found immediately to remedy. If the sealing belt is used, some water can be slightly poured to wet the sealing edge, and then gently sweep it. If it still does not work, measures such as repair or replacement should be taken. In the process of vacuum treatment, the vacuum degree, dehydration time and dehydration amount should be recorded carefully, and the water flow in the air cushion film should be observed everywhere. If the local water movement is not smooth, the adjacent sealing edge can be raised at short intervals to infiltrate a small amount of air and promote the water movement in the surface layer of concrete. When the dehydration reaches the required time (dehydration time is generally 1-1.5 times of the thickness of the plate (cm), unit min) or the required amount of water has been removed (dehydration rate is generally 12%-15%), slightly lift 1-2 cm around the suction pad and continue to suck 10-15S to remove the remaining water from the working surface and pipeline.

Roll up the suction pad, move to the next working surface and continue vacuum dehydration. The position of each suction pad should be overlapped with the previous 20 cm to prevent leakage and suction, resulting in uneven distribution of water content.

Vacuum dehydration of liquid ring vacuum pump should pay attention to the following matters:

The operation depth of vacuum dewatering should not exceed 30 cm and the water cement ratio of mixture should not exceed 0.55.

When purchasing filter cloth and suction pad, the appropriate size should be selected according to the size of concrete pavement plate. Too large or too small will affect the dehydration effect.

Vacuum operators must stand on self-made “work bridge” and not walk on suction pads at will. Do not wear shoes with hard soles and nails. It is better to wear rubber shoes or sneakers.

When dewatering, we should make a good record, grasp the uniformity of dewatering time, and prevent concrete from “spring layer” and cracks.

When the suction pad is stored or moved, contact with hard objects with sharp corners should be avoided. When rolling up or laying down the suction pad, you should hold the support stick in your hand. In order to avoid damage to the suction pad. After the construction of each shift, the suction pad should be washed clean, and the sediment of the vacuum pump box should be flushed out to drain the stored water.

Joint treatment: Joint slab is not used in construction joints, but only seam slab is placed on top of concrete slab. After the concrete is solidified, the expansion joints and construction joints are pulled out in time, and then filled with filling materials. The construction of shrinkage joint adopts the method of cutting joint. That is to say, when the concrete reaches 50-70% of the designed strength, it is cut into joints with a slitting machine and the width of the joints is 3-5 mm.