Study On Phosphogypsum-based Building Putty And Stucco Material

Phosphorus gypsum is mainly from the solid waste of the phosphate fertilizer industry. China as a large agricultural country, has a huge industrial base, the production of phosphate fertilizer in the traditional wet process phosphoric acid production process, in the process of production of a large number of phosphorus gypsum waste. Per production 1 ton can produce 4.5~5.5 tons of phosphogypsum, phosphate and diammonium phosphate can emissions per production 1 ton of 2.5~5 tons of phosphorus gypsum. In recent years, our country phosphogypsum emissions increasing year by year, annual emissions is close to 60 million tons, as well as the huge stock of both. Phosphogypsum commonly used way to deposited in the open air, land and air pollution, causing the destruction of the ecological environment, also has brought the serious negative impact to the society, also became one of phosphate fertilizer production enterprises heavy burden. Phosphogypsum effective composition content is higher, through certain pretreatment of removal of harmful impurities, can be a good gypsum resources. Group in phosphogypsum impurity type, shape, to the influencing factors and laws of phosphogypsum, pretreatment and the preparation of building gypsum has done a lot of basic research. In this paper, on the basis of exploring beta- half water phosphogypsum in the building putty and the application of painting materials, utilization of phosphogypsum in the good way.Phosphogypsum impurities, unstable performance, low-grade and other characteristics, has become an important factor restricting phosphorus gypsum-based material application development. Use building phosphogypsum as putty and paint the base construction material, there is a shorter operating time, poor construction performance, poor water resistance, low intensity, easy to crack and other defects, cannot meet the appropriate specifications. This selection of pretreated phosphogypsum as the main building material, trying to be incorporated in retarding additives, water retention, bonding, enhance, six water, cracking its modified sufficiently improved construction of phosphogypsum each performance, the final preparation of a good performance phosphogypsum base building putty and paint materials.By studying the impact of different types of buildings retarder phosphogypsum setting time and strength to find the best adaptation, best of retarder, change in crystal hardened scanning electron microscope observations, analyzes crystalline grain appearance of The intrinsic link with performance changes; study different types of cellulose ether and water repellent effect on building phosphogypsum retention and water resistance, and by observing the change in cellulose ether incorporated into the hardened body of crystalline appearance and to find the law; by subtracting agent and a binder to improve the strength of phosphogypsum building is an important means of measures herein modified, compared to the other properties on the basis of increase in strength, find the right type and dosage; polypropylene fiber construction phosphorus Effect of plaster cracking performance was characterized mainly by the flexural strength, and with the morphology was observed by scanning electron microscope, and identify the impact of law and reason. Mastered the additives on the basis of the law on the phosphogypsum modified by the addition of additives and fillers complex, formulated a good performance phosphogypsum base building putty and paint materials.Results show that the control between 0.06~0.1% dosage of modified protein retarder, PE retarder can significantly extend the setting time, meet the putty and paint material construction can be operation time, less negative effects at the same time the strength of gypsum material; Dosage is 1% of 4115 latex powder, improving the bond strength of phosphogypsum building and prolong the setting time, comprehensive performance is better; 0.2% dosage of methyl cellulose water retention effect is best, and minimal damage to strength; Organic silicon hate water content was 0.1%, significantly improve the water resistance of phosphogypsum buildings performance; Powder for poly(carboxylic acid water reducing agent can significantly reduce water consumption, improve the strength of the phosphorus gypsum sclerotium, dosage should be controlled between 0.5~1.0%; Length to diameter ratio of 400 was 0.04%, the dosage of polypropylene fiber on flexural properties of phosphogypsum building the best, best flexibility.Final preparation of the excellent performance of ordinary putty, flexible putty, water resistant putty and stucco gypsum. Water resistant type phosphorus gypsum putty table dry time of up to 101 min, bond strength before and after immersion were 0.63 MPa and 0.41 MPa, water retention rate of 86.9%, initial dry crack resistance, construction, grinding, water resistance are all good and above. Stucco gypsum final setting time at the beginning of 118 min and 151 min, respectively water rate was 94.7%, the flexural compressive strength 5.98 MPa and 18.76 MPa, respectively, the tensile bond strength of 0.7 MPa. This study were the four walls of paint products can meet the requirement of national standard and, applied to the development of phosphorus plaster base powder materials has a certain guiding significance.