Construction waste treating and recycling method

Abstract

The invention discloses a construction waste treating and recycling method. The method comprises the following steps: (1) properly smashing construction waste through a smasher, and initially sorting in a manual and / or mechanical way; (2) performing first-stage smashing and magnetic separation on remaining materials, sorting out small-piece metal materials, adding water into the materials for cleaning, and performing flotation to sort saw dust and small-piece plastic parts out; (3) performing second-stage smashing on the materials treated in the step (2) to generate aggregate for use in subgrade pavement; (4) screening burnt dust slag, separating powder and stone particles out, adding a certain amount of curing agent into the obtained powder, and performing conventional treatment to obtain cement. By adopting the method, the comprehensive utilization ratio of construction waste can be increased fully and effectively, and environmental pollution caused by construction waste is lowered.

Description

technical field [0001] The invention relates to the technical field of construction waste treatment, in particular to a construction waste treatment and recycling method. Background technique [0002] At present, the vast majority of construction waste is picked up and transported to the suburbs for stacking without treatment, occupying a large amount of production land. If it is not processed and utilized in a timely manner, the contradiction of land occupation will become more and more serious. In addition, after the construction waste is poured by rainwater at the dump site, a large amount of hydrated calcium silicate and calcium hydroxide contained in waste mortar and concrete blocks, a large amount of sulfate ions contained in waste gypsum, and a large amount of heavy metal ions contained in waste metal are dissolved. At the same time, waste cardboard and waste wood undergo anaerobic degradation to produce lignin and tannic acid and decompose them into organic acids. Th...

AI Technical Summary

Problems solved by technology

Furthermore, waste gypsum in construction waste contains a large amount of sulfate ions, which will be converted into hydrogen sulfide gas with the smell of rotten eggs under anaerobic conditions, and waste cardboard and waste wood will undergo anaerobic degradation to produce lignin and tannin And decomposed into organic acids, these harmful gases will seriously pollute the atmosphere

Polluted soil The harmful substances produced above will pollute the soil, affect the nutrient absorption and growth of plants, and destroy the ecological balance inside the soil