When it is used in the field, the effect of polyacrylamide can be reflected in three aspects: sedimentation, air flotation and sludge dewatering. When the effect is sedimentation and air flotation, we can observe the reaction speed and water clarity. When the effect is sludge dewatering, we should not only observe the reaction speed and water clarity, but also observe the size of sludge volume, floc size and water content of sludge cake, so as to make it convenient on site Different treatment process will affect the usage and treatment effect of the product.For all dehydration equipment, we need to detect the following parameters: sludge flow, sludge concentration, flocculant flow, polyacrylamide concentration, post dilution water flow and dosing point.When the site is a belt filter, the following problems should be paid attention to:

1、 In case of poor filtration, we should solve the problem from the following three aspects:1. Mixing conditions: such as adjusting the mixing intensity, finding the better dosing point and checking the adhesion of sludge on the filter cloth.2. Flushing system: such as flushing flow, water pressure, nozzle condition and pressure.3. Flow: in order to improve the effect, adjust the sludge flow, polymer flow and post dilution flow.

2、 When the sludge is extruded, we should consider the following three aspects:1. Flocculation: reduce the dosage to a lower level and add from less to more.2. Check the filter: check the washing condition of the filter belt.3. Check the inlet sludge: if the solid content of the inlet sludge is too high, there will be problems. Attention should be paid to reduce the sludge flow and the width of sludge in the filter area, and increase the sludge thickness.

3、 When the moisture content of mud cake is low, the following three aspects should be considered:1. Check the mixing conditions: if the mixing is not uniform, the degree of biscuit will be reduced. Adjust the mixing conditions and improve the dosing point.2. Check the belt speed and pressure: if the belt speed is too fast, the dewatering time is too short. By reducing the belt speed and prolonging the filtration time, the dewatering effect can be improved, and the belt pressure can be increased to obtain better mud cake parameters.3. Test the type of polyacrylamide: change the molecular weight, adjust the concentration of polyacrylamide, dilute after adjustment.