Stabilization of Solidified and Virgin Fly Ash by Hydrostatic Pressing

Abstract

The invention relates to a method for achieving stabilization of solidified fly ash and protogenous fly ash through static-pressure pressing. Firstly, the solidified fly ash is added to the protogenous fly ash, the mass of the added solidified fly ash is 1%-99% of the total mass of the solidified fly ash and the protogenous fly ash, and the solidified fly ash and the protogenous fly ash are mixed evenly; then the mixture is loaded into a high-pressure-resistant die, and a hydraulic machine is used for pressing after the die is fixed; the pressure is controlled to be 5-5000 MPa, and the pressure maintaining time is 0.05-120 min; a fly ash die block is obtained after the die is removed, and the content of heavy metals in the fly ash die block like Cu and Hg is zero, the contents of Cr, Pb and Zn are significantly reduced, and the contents of other heavy metals are all below the detection limit through detection. The size of the fly ash die block and the leaching toxicity are significantly reduced; a solidification agent is fully used.

Description

technical field [0001] The invention relates to a static pressure pressing method for stabilizing solidified fly ash and original fly ash, and belongs to the technical field of waste incineration fly ash treatment. Background technique [0002] Domestic garbage, municipal sludge and other wastes in our country are produced in large quantities every year. One of the treatment methods is incineration, but incineration will produce bottom ash and 3% to 5% fly ash which account for about 23% of the total garbage. Among them, the fly ash is produced by the flue gas produced by the incinerator after being neutralized and purified by the reaction tower, mixed with a certain amount of adsorbent, and then separated by a high-efficiency dust separator. Fly ash mainly consists of SiO 2 , CaO, Al 2 o 3 , Fe 2 o 3 Reactants such as sulfate, sodium salt, and potassium salt, as well as heavy metal elements such as Hg, Mn, Mg, Sn, Cd, Pb, Cr, and trace-level organic substances such as ...

AI Technical Summary

Problems solved by technology

The steps of the stabilization treatment method are generally to take a certain amount of the above-mentioned stabilizer and dissolve it in an appropriate amount of water to make a solution, then add the aqueous stabilizer solution to a certain amount of incineration fly ash, stir evenly, and make a stable matrix solid; The mixing ratio of stabilizer and waste incineration fly ash is generally 1:100~5:100. If the curing agent is too much, the utilization rate is low, resulting in waste of expensive chemicals.