The snail sludge dewatering machine can not press the mud can be described as the following conditions:
1. Mud running and mud leakage when working
2. The sludge efficiency is low, the sludge cake is thin, and the processing capacity is small;
3. The moisture content of the mud cake is high, exceeding 80%
Low sludge concentration is the main reason for sludge concentration, which is often referred to as sludge solids content. Sludge solids content is less than 1%, direct mechanical sludge dehydration is not ideal, and the demand for flocculants increases. If domestic sludge or viscous industrial sludge with a concentration of less than 1% enters into the snail, it will cause a leakage of mud, and the sludge cannot be pressed out, and the treatment efficiency is low. The traditional method is to increase the sludge concentration tank in civil engineering. The plate and frame sludge thickener solves this problem very well. After the sludge thickener is concentrated, the sludge concentration can be increased to about 3.5%-11%, which is very suitable for entering the screw stacker for pressure filtration and dehydration process, avoiding The sludge concentration is too low to cause sludge leakage. It is widely used in domestic sewage with large sewage volume and low solids content.
The flocculation effect of sludge is not ideal, and the plate-and-frame filter press dehydrator is more dependent on the conditioning. If the dosage is insufficient and the conditioning effect is not good, the capillary water in the sludge cannot be converted into free water and removed in the gravity zone, so the sludge entering the low-pressure zone from the mold zone is still fluid and there is no way to squeeze Pressure. On the contrary, if the amount of drug added is too large, one is to increase the treatment cost, and more importantly, because the viscosity of the sludge increases, it is easy to cause the filter belt to be blocked. For urban sewage mixed sludge, when using cationic PAM, the dosage of dry sludge is generally 1 to 10 kg/t, which can be determined by experiment or adjusted repeatedly during operation.