Inorganic composite conditioner for effective sludge dehydrating

Abstract

The invention discloses an inorganic composite conditioner for effective sludge dehydrating, comprising an inorganic high valent cation coagulant, quicklime and inorganic powder fine aggregate, wherein the weight percentages are as follows: 2-10% of the inorganic high valent cation coagulant, 30-50% of quicklime and 40-67% of inorganic powder fine aggregate. The invention also discloses a use method for the inorganic composite conditioner. The conditioner disclosed by the invention can obviously lower specific resistance of sludge (SRF) and capillary suction time (CST) so as to large raise the sludge dehydrating performance. In addition, the drugs of the conditioner are cheap, and the organic contents of the sludge cake after dehydrating are low, and the inorganic material compositions in the conditioner are helpful for forming the strength during the subsequent preparation of backfilling mulching soil and building materials, and the sludge cake after dehydrating can be used as a raw material for preparing the backfilling mulching materials and the building materials.

Description

technical field [0001] The invention relates to sludge treatment technology, in particular to an inorganic composite conditioner for treating sludge with a water content as high as about 97%. Background technique [0002] The sludge produced by urban sewage treatment plants with a moisture content of about 97% is a hydrophilic organic aggregate mainly composed of extracellular polymers (ECP). Regular, non-uniform height, extremely high specific surface area and porosity (porosity is often greater than 99%); high organic content, easy to rot and smell; fine particles, small specific gravity; high moisture content, not easy to dehydrate. The current dehydration technology generally adopts polyacrylamide (PAM) flocculant conditioning and then undergoes mechanical dehydration, and only mud cakes with a moisture content of about 80% can be obtained. Generally, thermal drying technology with high energy consumption and high operating cost is required to further dewater deeply to ...

AI Technical Summary

Problems solved by technology

When the treatment effect is good, the content of organic polymer dehydration conditioner is high, the cost is high, and it is difficult to reuse the dewatered cake

In CN1986788A, the sludge is tempered by adding water first, and then adding iron salt, calcium salt or calcium oxide step by step. Although the dehydration effect is still good, the dosage of calcium salt or calcium oxide is too large, and the mud cake is highly alkaline.

The sludge dewatering agent disclosed in CN101100345A is aimed at dewatered sludge with a water content of about 80%, and the surface active ion dispersant is as high as 5%, and the surfactant in the filtrate will inevitably increase, causing secondary pollution

The composition of composite filter aid in CN101182095A includes as many as 9 kinds, and the preparation process is complicated

The disadvantage is that the dosage is too large, which is 5-20% of the mass of the water-containing sludge, which will inevitably lead to a large increase in sludge volume.

CN1016...