Views: 0 Author: Site Editor Publish Time: 2020-05-09 Origin: Site
The characteristics of the valveless filter of the diaphragm filter press
1. Backwashing is automatically formed and stopped. There are two issues worth noting here. First, during the backwashing process, as the water level of the flushing tank drops, the flushing strength gradually decreases, which is quite beneficial to the flushing effect; second, during the backwashing process, the filter of the diaphragm filter press The water is constantly being fed in and discharged together with the backwash water, causing water loss.
2. The automatic backwashing of the valveless filter tank of the diaphragm filter press can only be performed when the head loss of the filter tank reaches the allowable head loss value at the end of the cycle. If the head loss of the filter has not reached the allowable value, and for some reasons, backwashing is required in advance, forced backwashing must be used. For this reason, a forced flushing device is provided in the valveless filter tank, which is a pressure tube inserted in the upper part where the siphon auxiliary pipe is connected to the suction pipe. When forced backwashing is required, open the inlet valve on the pressure pipe, and the high-pressure water flow will quickly draw the air out of the siphon tube, causing siphon formation.
3. Constant water filtration with variable head. During the filtration process, the water level in the siphon riser rises as the filtration time continues, the amount of suspended matter in the filter layer increases and the resistance of the filter layer increases. Therefore, under the condition that the water output is constant, it is in a state of constant-speed filtration with variable head until the backwash starts.
4. Adopt small resistance water distribution system. Due to the structural characteristics of valveless filter tanks, low water head backwash is usually used, so only low resistance water distribution systems can be used. In thermal power plants, the water distribution system of valveless filters is mostly grid type.