Study On Preparation Of Autoclaved Silicate Materials By Soda Residue And Ceramic Polishing Residue

Soda residue and ceramic polishing residue are the waste residue produced in the process of industrial production of soda and building ceramic tile respectively.The production of soda and ceramic tiles in China is huge,and a lot of waste residue are brought in the industrial production.At present,the main treatment methods of the two industrial wastes are stacking and storage and shallow landfill treatment,but the methods seriously damage the ecological environment,waste land resources and cause serious damage to human health.The resource treatment of industrial waste residue is an urgent problem to be solved.In this paper,the soda residue discharged by Guangdong Nanfang soda Industry Co.,Ltd.and the ceramic polishing residue discharged by Dongpeng ceramic factory in Foshan,Guangdong Province are studied.Based on the study of different treatment methods of soda residue and ceramic polishing residue(one of which uses the common clay mineral kaolin),this paper puts forward the technical route of preparation of silicate materials by soda residue-kaolin mixed low-temperature calcination,and studies the process parameters of soda residue-kaolin mixed calcination and the key technologies.of preparation of autoclaved silicate materials by industrial waste residue.The autoclaved silicate material with compressive strength of46.0Mpa,water absorption of 8.0% and softening coefficient of 0.93 is prepared,which provides theoretical support for the comprehensive utilization of industrial waste.In this paper,the particle size of soda residue,ceramic polishing residue and kaolin are analyzed.Three different treatment methods are used for soda residue,such as drying and milling,high temperature calcination and mixed with kaolin at low temperature calcination.The ceramic polishing residue is dried and milled.The results show that the fine powders made from crushed soda residue and crushed ceramic polishing residue can be used as mineral admixtures and siliceous materials of autoclaved silicate materials respectively;After calcining at 900 ℃ for 2 h,soda residue can be used as calcium raw material to prepare autoclaved silicate materials;The results show that the best dispersing performance of 8:2soda residue-kaolin mixture is that of adding 120% water and 3% naphthalene dispersant.Then the production technology,the best mixing amount and the best proportion of autoclaved lime sand products were studied by ball milling,calcined soda residue and ball milling ceramic polishing residue.The influence mechanism of the waste residue on autoclaved ash sand products was analyzed by XRD and SEM.The results show that the properties of the products can be improved when the content of ball milled soda residue is less than 8%,and 4% is the best;With the increase of calcined soda residue content,the performance of lime sand products first decreases and then increases.When the content exceeds 20%,the performance decreases.The product with 20% calcined soda residue has the best performance.When ceramic polishing residue replaces grinding sand powder as silicon material,the product performance increases with the increase of the amount of ceramic polishing residue.Through XRD and SEM analysis,it is found that the reason for the performance change of autoclaved lime sand products is that the type and quantity of hydrated calcium silicate formed under autoclaved conditions are changed after adding different raw materials.Finally,the technical route of preparing autoclaved silicate material by mixed calcination of soda residue kaolin is put forward.Through experimental research,the best calcination process parameters of soda residue-kaolin mixture are found.The best addition,proportion and ratio of the mixture of soda residue-kaolin with cement,grinding sand powder,fine sand and ceramic polishing residue are studied Meanwhile,XRD and SEM were used to analyze the phase and morphology of the autoclaved silicate materials.When 8:2 ratio soda residue-kaolin mixture was treated at 700℃ and calcination time for 3 hours,the main phases of calcined materials were C12A7,C2 S,Ca SO4 and non reactive calcium carbonate crystals.At the same time,it was found that the calcined materials would produce hydrated garnet under the condition of autoclaved water heat.The autoclaved silicate products with excellent performance can be prepared by the mixture of soda residue-kaolin calcined material with cement,sand powder,sand and ceramic polishing residue under certain pressure.Based on the cost factors,the optimum ratio of the new autoclaved silicate material is 45% 8:2 soda residue-kaolin calcined material,5% cement,20% grinding sand powder and 30% ceramic polishing residue.The best forming pressure is 20 MPa.The compressive strength of the test piece is 46.0Mpa,the bulk density is 1810kg/m3,the water absorption rate is 8.0%,the softening coefficient is 0.93 under the condition of 1.3Mpa pressure,192℃ temperature and8 h constant temperature.One of the important strength sources of autoclaved silicate products is CSH(B),tobermonite and aluminum tobermonite which are transformed by C12A7 and C2 S.In this paper,the soda residue and ceramic polishing residue were successfully used to prepare autoclaved lime sand products and autoclaved silicate products.Autoclaved lime sand products with properties higher than MU30 grade in GB/T 11945-2019 autoclaved lime sand solid bricks and solid blocks and autoclaved silicate products with properties higher than MU40 grade in CJ/T 400-2012 recycled aggregate floor tiles and permeable bricks were prepared.This paper is innovative and has remarkable results.