Method for efficiently dewatering of sludge

Abstract

The invention relates to a method for efficiently dewatering of sludge. The method comprises the following steps of: adding an organic flocculant and a physical conditioner to a gravity thickening tank, wherein the amount of the added organic flocculant is 0.2 per mill to 5.0 per mill of the dry weight of the thickened sludge, and the amount of added physical conditioner is 1% to 10% of the dry weight of the thickened sludge; tempering: adding a calcium coagulant aid to the sludge slurry based on the amount of 1% to 5% of the dry weight of the thickened sludge; and then adding a ferrum flocculant after 1 to 10 minutes based on the amount of 0.5% to 5% of the dry weight of thickened sludge; reacting for 1 to 20 minutes; dewatering: introducing the tempered sludge into a plate-and-frame filter press through a pneumatic diaphragm pump, and charging for 20 to 30 minutes, and dewatering at 0.5 to 2.5Mpa; and discharging: discharging the dewatered sludge from the plate-and-frame filter press. According to the method, the chemical and physical combination mode is adopted to condition for boosting coagulation in the sludge thickening stage; the inorganic flocculant and the coagulant aid are added for further preprocessing in the sludge tempering stage; mechanical equipment with relatively high pressure is adopted to dewater, so that the effect of dewatering can be further improved, and efficient dewatering of the sludge in the urban wastewater treatment plant can be achieved.

Description

technical field [0001] The invention relates to a novel method for highly efficient dewatering of sludge in urban sewage plants. Background technique [0002] The treatment and disposal of urban sewage plant sludge (hereinafter referred to as urban sludge) has become a difficult and hot point in municipal engineering. According to the principle of adapting measures to local conditions, there are many options for sludge treatment and disposal, but reducing the moisture content of sludge and achieving efficient dehydration of sludge to reduce the moisture content to 60% or even below 50% has become the most important sludge treatment and disposal process. link. Municipal sludge is composed of hydrophilic and negatively charged colloidal particles, which have a strong affinity with water. Without proper pretreatment, dehydration is difficult. [0003] The water contained in municipal sludge can be roughly divided into four categories: interstitial water between particles, acc...

AI Technical Summary

Problems solved by technology

[0005] Aiming at the problem of low efficiency of the traditional sludge dewatering method, the present invention provides a high-efficiency sludge dewatering method. The method adopts chemical and physical combination conditioning coagulation aid in the sludge concentration stage, and adds inorganic flocculant in the sludge conditioning stage. and coagulant aid for further pretreatment, and use high-pressure mechanical equipment for dehydration to further improve the dehydration effect and realize efficient dehydration of urban sewage plant sludge