How to debug the plate and frame filter press when using polyacrylamide desliming

When the plate and frame filter press is used at the sewage desliming site, we select the model through the polyacrylamide "beaker experiment" and equipment trial operation. When doing a polyacrylamide beaker test, it should be observed: floc strength, floc size, reaction speed, sewage clarity, etc. The experiment of polyacrylamide during the trial operation of the equipment should be observed: pressure, filtration cycle, polymer dosage, sludge flow, mud cake texture, sludge dryness, etc.

When the following problems occur, we should make adjustments based on the corresponding content.

◆ Mud cake sticky filter cloth

1. Check the dosage of coagulant. Addition of coagulant at a later stage can reduce viscosity.

2. Check the cleaning condition of the filter cloth (if the filter cloth is too dirty, it is impossible to obtain a good desilting effect, the filter cloth should be rinsed regularly with a high-pressure water gun)

3. Check the choice of flocculant (if the flocculant is not properly selected, the mud cake will be sticky, pay attention to the molecular weight and dosage of polyacrylamide when doing beaker experiments in the laboratory)

◆ The filter cloth is blocked

1. Check the boost pressure. At the beginning of each cycle, the pressure should increase slowly in a small test. Check this parameter and find the connection between it and the mud.

2. Check the cleaning condition of the filter cloth. If the filter cloth is dirty and clogged quickly, it should be rinsed before each new experiment.

3. The size of the floccules. To get a good filtering effect, small and shear-resistant flocs are needed. At this time, we should adjust the molecular weight or molecular structure of polyacrylamide.

◆ the polymer loses its effect

1. Check the configuration of the polymer, whether the solution degrades over time or uses a high-speed shear pump to destroy the molecular structure of polyacrylamide.

2. Check the PH value of the inlet mud. If the inlet mud pH is high, the cationic polyacrylamide will quickly fail. If the pH is too high or too low, it will affect the flocculation effect. If conditions permit, the pH value should be adjusted in advance.

3. Check the mixing effect and select the appropriate dosing point to fully mix the sludge and flocculant.