Optimizing method of phosphogypsum-based cementitious material to improve filling rate

Abstract

The invention discloses an optimization method of a phosphogypsum-based cementitious material that improves the rate of filling and roofing. In the method, different ratios of phosphogypsum powders and activators are added to the filling aggregate to make cemented fillings with different ratios. Carry out the cemented filling body strength test and the filling body expansion rate test for the cemented filling body materials of different proportions, and obtain the test data of the cemented filling body strength and expansion rate of the cemented filling body materials with different proportions; adopt the quadratic polynomial Carry out stepwise regression analysis on the test data of the strength and expansion rate of the above-mentioned cemented filling body; take the 3d strength of the cemented filling body as the optimization goal, and take the 28d filling body expansion rate as the constraint condition, establish the ratio optimization model of the cementitious material; solve According to the above optimization model, the optimal proportion of the phosphogypsum-based cementitious material in the filling slurry can be obtained. This design method can realize low-cost and high-value resource utilization of phosphogypsum; it can realize low-cost and high-value utilization of phosphogypsum in filling mining.

Description

technical field [0001] The invention belongs to the technical field of filling and mining, in particular to an optimization method for a phosphogypsum-based cementitious material that improves the rate of filling and roof connection. Background technique [0002] With the rapid development of my country's national economy and the continuous development of resources, high-grade and good-condition resources are increasingly depleted, and more difficult-to-mine ore bodies such as deep burial, high ground pressure, and rich water are faced with mining. For safety, environmental protection and green mining, the filling and filling mining method is the first choice. Especially for complex and difficult-to-mining ore bodies with weak and broken surrounding rocks, it is necessary to protect them under the false roof of the filling body to achieve safe operation, so the downward layered filling mining method is the only choice. This filling mining method has complicated mining proce...

AI Technical Summary

Problems solved by technology

[0003] Harmful mineral components in phosphogypsum lead to low activity, poor gelation, and volume instability, resulting in less than 5% utilization of phosphogypsum

This treatment can improve its early strength to a certain extent, but there is no reliable basis for the significance of the effect, and it is difficult to meet the early strength requirements of the downward layered filling method.

CN108191365A discloses a method of applying phosphogypsum material to cement and fill metal mines. Phosphogypsum is used as a filling cementitious material, and a filling process applied in filling mines is disclosed. Neither the strength of the phosphogypsum-based cementitious material nor the strength of the phosphogypsum-based cementitious material is considered. Involving slurry pipeline transportation characteristics

Obviously, these treatment processes and methods not only increase the production cost of cementitious materials, but also a series of treatment processes such as mixed grinding and calcination also pollute the environment, which is not conducive to the low cost and large-scale utilization of phosphogypsum

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