Municipal sweage wastewater generally contains solid material consisting of organics, cellulose, starch, sugar, lipids proteins, as well as microbiology such as bacteria and virus. Sewage pH is typically neutral or acdic . we normally use cationic flocculant, it may be beneficial to use an inorganic coagulant such as PAC if the ionic charge of the sewage is very high.
The sludge produces as a waste product of treatment has a pH value generally between 5.5~7.5. Its consistency can range between 1% up to 4% and further dewatering will be required. Sludges are usually treated by cationic polymers prior to use in a thickening device such as a belt press, centrifuge or screw press. The PAM dosage depends will depend on the equipment selected for dewatering and the desired % solids of the sludge.
Sewage is the waste water produced by the city offices, schools and residents in daily life. The water generally appears black and smells badly which is because it contains a large number of organics, such as cellulose, starch, sugar and fat proteins, etc. It often contains bacteria and virus and its PH value is mostly neutral. It is better to treat it with anion and PAC. In some cases, we can also use cationic with low ionic degrees and inorganic PAC to deal with it. A ton of water consume 480g PAC and 3g ~ 10g PAM. The COD is generally reduced 100 ~ 200mg / L, which can meet the national standards of emission with follow-up treatment process.
Sludge is the solid part of the sewage whose PH value is generally 5.5 to 7.5 with appearance of dark brown and also smelly. It is the thick thing between liquid and solid, which is hard to be separated by natural sedimentation. Sludge is usually treated by cationic. You can choose the models according to the nature of the mud, generally with neutral ionic degree. The sludge can be pressed directly by the filter press, achieving dewatering. It needs different usage with different solid clay. It is general to use 5 ~ 25g PAM in one ton of sludge.