Sludge concentration dehydration method

Abstract

The invention relates to a method of sludge concentration and dewatering which can treat sludge with different water contents and can recycle the treated sludge. The method comprises the following steps: (1) firstly the sludge is concentrated; (2) then modulating agent is added in the concentrated sludge to mix; the mixture is transported to a dewatering device to take dewatering; (3) when the dewatered sludge meets the requirement of the final disposition, the corresponding disposition can be carried out directly; the invention is characterized in that: before the sludge in the step (1) is concentrated, organic modulating agent is added to carry out a first modulating; before the concentrated sludge in the step (2) enters the dewatering device, inorganic modulating agent is added to carry out a second modulating. The method of sludge concentration and dewatering provided by the invention has high efficiency of sludge concentration and dewatering, has low energy consumption, reduces the water content at large amplitude, saves time of the operation processing, has low investment and operation cost and simple process operation.

Description

technical field [0001] The invention belongs to the field of sludge treatment methods, in particular to a sludge concentration and dehydration method capable of treating sludge with different water contents and reusing the treated sludge. Background technique [0002] For the current sludge treatment methods with different water contents, most of them use the method of first concentrating the sludge and then adding a conditioning agent for dehydration. The specific steps are as follows: first transport the sludge to the gravity concentration tank Concentrate, then add conditioner to the concentrated sludge and mix it, and then send it to the dehydrator for dehydration. When the dehydrated sludge meets the requirements for final disposal, it can be disposed of accordingly; when the sludge dehydrated by the dehydrator does not meet the requirements for final disposal, it can be further dried to make the dried sludge meet the final disposal requirements. required, and then pro...

AI Technical Summary

Problems solved by technology

[0003] The above-mentioned sludge treatment method has the following disadvantages: 1. The sludge after concentration has a high water content, long concentration time, and a large floor area of ​​the concentration tank

For its further treatment and disposal, due to the large amount and high moisture content, the use value is less than the treatment cost, which greatly limits the resource utilization

For example, the moisture content of sludge is high, and there is only 20% dry sludge in the sludge with 80% moisture content. The 80% moisture contained in it results in a large amount, large volume and high quality of sludge, which makes the treatment and disposal very difficult. Difficult, especially resource utilization, due to the high water content, the relative proportion of available sludge is very small, resulting in the cost of water removal is greater than the value of sludge, and it is difficult to use; 4. The energy consumption of drying treatment is large

The sludge with a moisture content of about 80% produced by the sewage treatment plant is directly dried to remove the moisture in the sludge. Because the moisture content in the sludge is too high, the amount of water evaporated by drying is large, and the evaporation of water is difficult, resulting in sludge drying treatment. It consumes a lot of heat, which leads to high energy consumption, high drying costs, and a large load and processing capacity of drying equipment, resulting in very expensive investment and operating costs for sludge treatment and disposal, which is economically unbearable; if further Drying treatment to a moisture content of 10%, the treatment capacity of sludge with a moisture content of 80% is twice that of sludge with a moisture content of 60%; the water that needs to be dried and evaporated, 1 ton of sludge with a moisture content of 80% will be 0.5 tons 2.8 times the evaporation of sludge with 60% water content

5. It is also very inconvenient for sludge to be loaded, unloaded and transported

The disadvantage of this method is that it is necessary to add filtrate to the sludge, so it is only suitable for the sludge after centrifugal dehydration. The sludge with a water content of 85-80% after centrifugal dehydration is diluted with filtrate to make the sludge water content The rate reaches about 90%, and then add Fe-containing chemical raw materials and Ca chemical raw materials for conditioning

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