1. Constant pressure filtration
In this case,
Filtration is carried out at a constant pressure differential, called constant pressure filtration. Constant pressure filtration is the most commonly used filtration, filtration process, with the cake layer of the continuous thickening, resistance increases, due to pressure difference, the filtration rate will gradually decrease.
In this case,
2. Constant speed filtration
In this case,
The filtering operation is carried out at a constant speed, called constant speed filtration. As the filtration time continues, the thickness of the cake layer increases and the resistance increases, and the pressure drop across the filter increases linearly over time. Pressure equipment, the pressure capacity is limited, the pressure can not be too high. For compressible filter cake, the excessive pressure increase does not increase the speed, on the contrary will cause the filter to terminate.
In this case,
3. Constant pressure after constant pressure filtration
In this case,
This filter is to start at a lower speed constant speed filtration, so as not to rise too early to form a flow channel blockage, when the pressure rises to a given value and then use constant pressure filtration. The pump outlet pressure increases, if the pressure rises to enable the bypass valve automatically open the set value, the branch open, part of the slurry back to the pump inlet pump inlet pressure, , Filter press into the filter to reduce the filter inlet pressure to maintain a constant, which began constant pressure filtration.