Method for preparing low-pollution boards from municipal sludge and carbide slag

Abstract

The invention relates to a preparation method of sheet materials with low pollution by using city sludge and calcium carbide slags. Base materials which comprise city sludge with wet basis, coal ash, calcium carbide slags and broken stone slags are metered separately; firstly, heavy metal ions in the city sludge with wet basis are solidified, cracking and carbonization pretreatment is carried out for a part of the city sludge after solidification treatment, and the rest part of the city sludge after solidification treatment and calcium carbide slags are mixed in order to carry out pretreatment by a sintering method; the base materials after the pretreatment are mixed, and a compression molding is carried out for molding; after molding, drying is carried out till the weight is constant; a blank is placed in a microwave sintering apparatus, pumping is carried out in order to form vacuum, CO2 is introduced in order to keep the pressure in the system constant, and after maintenance, the sheet materials are obtained. The method has the beneficial effects that solidification effects of the heavy metal are good, the removal rates of various heavy metals are higher than 90%, and the removal rates are not limited by kinds of heavy metals; the utilization rate of solid wastes is high, and the sheet materials are widely suitable for usage in life and production.

Description

technical field [0001] The invention belongs to the technical field of sludge resource utilization, in particular to a method for preparing low-pollution boards by using urban sludge and carbide slag. Background technique [0002] Our country is a country with a lot of people and little land and resources are tight. In my country, with the continuous advancement of urbanization level construction, and from the national level to the general public, the awareness of environmental protection has become stronger and stronger. In recent years, the number of sewage treatment plants has increased sharply, and the resulting The amount of sludge (including various heavy metal ions, etc.) is also increasing. According to statistics, by 2020, my country's urban sludge discharge (dry weight) will reach 60 million tons. How to efficiently and rationally utilize these wastes and realize the rationalization and resource utilization of wastes has become an urgent problem to be solved at pr...

AI Technical Summary

Problems solved by technology

[0005] ① Municipal sludge contains a large amount of heavy metal ions, which will cause great harm to human life and production. As far as the current technology is concerned, there is no good solution, and sludge is blindly made into building materials Applied in daily production, as time goes by, the heavy metal ions in it will slowly leach out, causing harm to people's health

[0006] ② There are also a large amount of domestic garbage and urban pollutants in the urban sludge, which contain a large number of germs and harmful microorganisms. Not only is a lot of resources and fuel wasted, but also the harmful gas produced by incineration will pollute the air and cause serious harm to nearby people.

It uses sludge dehydrating agent and deodorant to dehydrate and deodorize sludge. Zhejiang Lvtian Environmental Engineering Co., Ltd. discloses a degradable sludge plastic environmental protection board and its preparation method (patent publication number: CN104591682A), It uses sludge, wood flour, PP powder, and various admixtures for secondary demoulding, granulation, and grouting. However, the durability and thermal insulation properties of the panels obtained by this method cannot be guaranteed, and this method is harmful to The heavy metal ions and organic matter in the sludge have not been well treated, only additives are added to fix them, and it is difficult to use them for a long time