Modified ardealite setting retarder for cement and its preparing process

Abstract

The invention discloses a modified phosphogypsum cement retarder and the preparation method thereof, comprising the following steps: performing composite modification to the industrial residue phosphogypsum by using acetylene sludge and fly ash which are also industrial residues, meanwhile, adding the glauber-salt powder used as a cement excitant and / or triethanolamine scrap used as a cement grinding aid, wherein the weight percentage of the components thereof is: 90 percent to 95 percent of phosphogypsum, 3 percent to 7 percent of acetylene sludge, 1 percent to 5 percent of fly ash, 1 percent to 3 percent of glauber-salt powder and / or the triethanolamine scrap; the materials are put into a storage hopper, then crushed, balled by a telescopic pelletizer and dried so as to finally obtain the product. The cement retarder prepared through the adoption of the invention can accelerate the hydration, promote the condensation of the cement, improve the initial strength of the cement and eliminate the influence of the soluble minor components upon the hydration of the cement; moreover, the cement retarder contains little moisture in the obtained balls, is stored for a short time, not only utilizes the waste but also is environment friendly, thereby achieving the aims of comprehensively using the waste residue resources and saving resources,; and the cement retarder has low cost, thereby enhancing economic returns for enterprises.

Description

technical field [0001] The invention relates to a phosphogypsum cement retarder, in particular to a modified phosphogypsum using industrial waste residue as a cement retarder and a preparation method thereof. Background technique [0002] Phosphogypsum is industrial waste slag discharged during the production process of phosphorus chemical enterprises. The stacking of phosphogypsum not only takes up a lot of space and money, but also pollutes the environment. Using industrial waste phosphogypsum as a cement retarder can improve the utilization rate of waste residue, reduce the pollution of waste residue to the ecological environment, reduce the accumulation of waste residue to occupy cultivated land, save energy, and reduce production costs. There have been related reports in public publications. [0003] The current phosphogypsum modification technology is to add quicklime to the phosphogypsum, dry it with a dryer at a temperature of 800°C, and then add water and granulate ...

AI Technical Summary

Problems solved by technology

However, the research shows that there are still the following defects: in the formula, the amount of phosphogypsum used is small, so that the cement is slow in the hydration process, the coagulation force is poor, and the early strength is low. Large (about 20% water content), naturally dried and stored for a long time

Images