Anionic Polyacrylamide Improves Sludge Thickening Efficiency

After using an anionic polyacrylamide flocculant, sometimes the effect can not meet their requirements. So how to operate to achieve normal processing efficiency?

1. Use low-dose flocculant anionic polyacrylamide

Sludge with different properties has strict requirements for its dosage and selection. For example, anionic polyacrylamide for sludge thickening is divided into a low, medium, and high ionic degree. If it is too high or too low, the refining efficiency will be uncoordinated. The initial load of the sludge refining tank shall meet the design requirements. If the sludge treatment capacity is too large, the clear liquid is dirty, the solid concentration of refined sludge is low, and the refining efficiency is poor. If the treatment capacity is too small and the sludge stays in the tank for too long, it may lead to anaerobic fermentation of sludge, making the sludge float up, and small bubbles escape from the liquid level, affecting the treatment efficiency.

2. How to apply anionic polyacrylamide in vacuum filtration？

In vacuum filtration, adding flocculant anionic polyacrylamide can improve the permeability of the filter bottle, increase the output of solid materials and greatly reduce the solid content in the returned sewage. The mixed-use of Cationic PAM with lime and polymerized NaCl can reduce the problem of excessive sludge when using inorganic coagulant alone.

In the vacuum filtration of the sewage treatment plant, when the inorganic coagulant becomes polyelectrolyte, the change of floc size should be studied to select the appropriate filter cloth to prevent the floc from leaking from the filter cloth hole. Cationic PAM can be used for centrifugal dehydration to improve the strength of flocs and increase the efficiency of solid-liquid separation. Cationic PAM can also be used to increase the consistency of sludge and produce flocs with larger size and higher strength.

3. Cause analysis of adding PAM in the sludge thickening process

PAM is short for Polyacrylamide, which is a high molecular polymer. It has many functions. Its function in sludge thickening is to combine with the sludge to produce large flocs. After the water is filtered out through the filter cloth of the filter press, the water in the sludge is squeezed out through the filter cloth pressure filtration, and then the dry mud remaining on the filter cloth is scraped down and flows into the dry sludge tank. Alternatively, the water in the floc can be shaken off by the centrifugal force of the centrifuge, and then the sludge can be discharged for treatment. PAM plays the role of flocculation and dehydration here. It belongs to a kind of flocculant. Whether it is using board and frame, centrifuge, crawler, turbine, and other dehydration equipment, most of them increase its dehydration rate through the high-efficiency flocculation dehydration of PAM! Of course, some mud samples can achieve the effect of dehydration without adding chemicals.