Phosphogypsum consolidation diagenesis agent and preparation method and application thereof

Abstract

The invention discloses a phosphogypsum consolidation diagenesis agent and a preparation method and application thereof. The phosphogypsum consolidation diagenesis agent is formed by mixing a powderycuring agent A and a liquid curing agent B in the weight ratio of (9.2-9.99):(0.01-0.8), wherein the powdery curing agent A comprises, by weight, 98-99.9 parts of Portland cement and 0.01-2 parts of alginate, and the liquid curing agent B comprises, by weight, 92-99 parts of nano silicon dioxide solution and 1-8 parts of polyacrylic acid elastic emulsion. The powdery curing agent A in the phosphogypsum consolidation diagenesis agent is alkaline and is subjected to neutralization reaction with acidic phosphogypsum, phosphide and fluoride in phosphogypsum neutralize soluble phosphorus and fluorine and are converted into insoluble calcium phosphate and calcium fluoride substances, and attached water in phosphogypsum is absorbed, so that the water content of phosphogypsum is reduced, and phosphogypsum is solidified. The liquid curing agent B and the hydration product, namely silicate gel in the powdery curing agent A are subjected to colloid chemical reaction under the action of compactionpower to generate a structural body of silicon-oxygen tetrahedron to achieve the consolidation diagenesis function.

Description

technical field [0001] The invention relates to the technical field of road curing materials, in particular to a phosphogypsum compaction rock-forming agent and its preparation method and application. Background technique [0002] Phosphogypsum is the production of phosphate fertilizer and solid waste is discharged when phosphoric acid is produced. About 4.5 to 5 tons of phosphogypsum are produced for every ton of phosphoric acid produced. There is a large amount of phosphogypsum produced in my country every year. Phosphogypsum has the following characteristics: Phosphogypsum is a powdery material with almost no plasticity, phosphoric acid, sulfuric acid and hydrofluoric acid remain in phosphogypsum, which is an acidic by-product (PH<3); phosphogypsum contains 25% ~30% free water with a vertical permeability coefficient of 2×10 -5 ~1×10 -3 . At present, the effective utilization rate of phosphogypsum in China is less than 10%. Only a very small amount of phosphogypsum ...

AI Technical Summary

Problems solved by technology

At present, the effective utilization rate of phosphogypsum in China is less than 10%. Only a very small amount of phosphogypsum is used to produce building materials, and the remaining huge amount of phosphogypsum is stored as bulk industrial solid waste. Gypsum contains harmful heavy metal compounds such as arsenic, cadmium, and mercury, which pollute the environment

What's worse is that when the pavement layer is laid later, these cracks will be reflected to the road surface, resulting in reflective cracks, causing large or small damage, thereby affecting the service life and stability of the road; the smoothness of the cement-stabilized gravel base is difficult Grasp, the gravel itself is all or small stone bodies are very small and unstable

When the gradation of crushed stones does not meet the requirements, and sometimes there are saline-alkali particle size crushed stones, it will be difficult to lay the road surface evenly, and the crushed stones cannot be well mixed with cement and other cementitious materials. Segregation occurs, and the strength of cement-stabilized graded crushed stone is not enough

The strength of the road is related to its bearing capacity and service life. The reason for the insufficient strength of the cement-stabilized macadam base is that the core of the base is not up to standard, and when the mixture is unreasonably graded and the amount of cement ash or fine particles is too small, it will lead to cement stability. The gravel base is not strong enough, which affects the bearing capacity and service life of the road