Process for dehydrating activated sludge by waste alkaline residue/alkali liquor

Abstract

The invention discloses a method for dewatering activated sludge by utilizing waste alkali slag / alkali liquor. The method of the invention mainly includes that the waste alkali slag / alkali liquor is first added with a certain amount of calcium oxide to be evenly mixed and then injected into activated sludge which goes through gravity settling, and evenly mixed; fully-dissolved polyacrylamide is then added and evenly mixed; the dry basis ratio of alkali slag, calcium oxide, polyacrylamide and activated sludge is 25 to 40 : 7 to 13 : 0.12 to 0.25:100; after being fermented and air-dried, dewatered sludge is served as agricultural fertilizer. The dewatering method of the invention has the advantages of low cost, high efficiency of sludge dewatering, good stability and low content of heavy metal in yielding sludge and achieves the purpose that the waste alkali slag is recycled to treat the waste by the waste; in addition, the alkali slag contains the elements of calcium, magnesium and a small amount of sodium, potassium, chloride, etc., which are necessary for the plant growth and can be used for making fertilizer in the agricultural production.

Description

Method for dehydrating activated sludge by using waste alkali slag / lye Technical field: The invention relates to the application of waste alkali slag / lye in the soda ash industry produced by ammonia-soda method, in particular to a method for dehydrating activated sludge by using the waste alkali slag / lye. Background technique: At present, the sludge dewatering process mostly uses high-molecular organic flocculants such as polyacrylamide, and there are also iron-based and aluminum-based flocculants. There are also reports abroad that use magnesium salts and zinc salts as flocculants. Domestic enterprises use lime And ferric chloride, to make activated sludge flocculation to achieve the purpose of mud-water separation. This method has a large content of heavy metals in the mud and the treatment effect is unstable. Invention content: The purpose of the present invention is to provide a method for dehydrating activated sludge by using waste alkali residue / alkali liquor, whi...

AI Technical Summary

Problems solved by technology

The purpose of the present invention is to provide a method for dehydrating activated sludge using waste alkali slag / lye, which can solve the problem of high cost of activated sludge treatment and the problem of final resource utilization