Compound bricks of phosphogypsum, and producing method

Abstract

This invention discloses a method for producing phosphogypsum composite bricks, which are produced from: steam-cured phosphogypsum 30-55 parts, gel material 10-30 parts, curing agent 5-15 parts, aggregrate 5-37 parts, and reinforcer 1-5 parts. The method comprises: (1) steam-curing phosphogypsum, mixing and strring with the other raw materials; (2) adding water so that the water content is 12-20%; (3) molding under 10-80 MPa; (4) steam-curing at high temperatures and high pressure for 5-24 h. The composite bricks have such advantages as high flexural strength, high compressive strength and good freeze resistance, thus can be used on main walls. The method efficiently and largely consumes phosphogypsum, thus saving soil resources and preventing environmental pollution by phosphogypsum piling. Besides, the method has high profit, and is environmentally friendly.

Description

technical field [0001] The invention belongs to the technical field of resource utilization of industrial waste residues, and specifically relates to a phosphogypsum composite brick and a production method thereof. The composite brick is produced by steaming and curing the industrial by-product phosphogypsum of a phosphorus compound fertilizer factory. Background technique [0002] As the country gradually strengthens the protection of land resources and the price of coal resources continues to be high, the past technology of using clay to sinter into bricks will be gradually eliminated, and will be replaced by non-sintered bricks that do not require sintering and whose main raw materials are industrial waste slag. The non-sintered brick technology adopts high-pressure molding, and the curing method adopts autoclaved curing or natural curing. The performance of bricks cured by high temperature and high pressure steam is more excellent and stable, so the non-sintered brick te...

AI Technical Summary

Problems solved by technology

[0005] Chinese invention patent application "Phosphogypsum Unburned Bricks and Its Production Process" (public number CN1277168A) presses phosphogypsum, sand and cement under high pressure and then naturally maintains it to obtain finished products. The disadvantage is that the raw materials have not been pretreated, and impurities in them will affect the bricks. performance, the stability of the performance of shaped bricks in the case of natural maintenance cannot be guaranteed

[0006] Chinese invention patent application "environmental protection high pressure non-fired phosphogypsum brick and its manufacturing method" (publication number CN1673154A) is that phosphogypsum, sand and admixture are pressed and formed at a pressure above 40MPa, and natural curing is adopted. The disadvantage is that the pressure is too large, and the additional The manufacture of the agent is cumbersome, the sand crushing increases the cost, and the natural maintenance cannot guarantee the long-term stability of the performance

[0007] Chinese invention patent application "high-strength phosphogypsum building block and its preparation method" (publication number CN1433989A) is to press phosphogypsum, aggregates, additives, etc. into high-pressure molding, and then use steam curing to obtain finished products. Pretreatment can easily lead to swelling and cracking of the brick body during steam curing, and the yield is low

[0008] The raw materials in the preparation of phosphogypsum bricks in the above-mentioned patents are not pretreated, which may easily lead to brick expansion and performance degradation, and generally adopts natural maintenance, and the stability of performance cannot be guaranteed, so there is no large-scale actual production application at present.