It is necessary to do polyacrylamide screening test with new sludge samples in the laboratory. After selecting the appropriate polyacrylamide in the laboratory, it is necessary to do the test on the sludge dewatering device. In order to ensure the success, the experimenter must carefully observe and control the following parameters:

1. Polyacrylamide dissolving tank capacity (L) and agitator speed (RPM)

2. Sludge flow into the dehydrator (m3 / h)

3. Solid content of sludge (g / L)

4. Flow of polyacrylamide into dehydrator (L / h)

5. Concentration of polyacrylamide solution (g / L)

6. If the flocculant needs to be diluted again before entering the dehydrator, the flow of dilution water shall be controlled (m3 / h)

7. The position of polyacrylamide injection and the number of injection points

8. Observe whether the mud cake and filtrate are normal

With the above parameters, we can control and adjust the working condition of flocculant on site, evaluate the working efficiency of flocculant, calculate the dosage of polyacrylamide needed to treat each ton of sludge (or solid matter), and estimate the cost of polyacrylamide for each ton of sludge.

Different sludge dewatering equipment (belt filter press, plate and frame filter press, centrifuge) will put forward different requirements for polyacrylamide in operation. Therefore, the field engineer should timely check and adjust the polyacrylamide variety, configuration concentration, dosage, input point and other parameters according to the situation of dewatering equipment.