Study On The Wet Casting Preparation Of Porcelain Building Ceramic Using Granite Waste

As China's reform and opening up,industrialization and urbanization progress,the scare of building ceramics will be further expanded over next few years,in the meantime,clay production slowed to a trickle which is high quality raw materials can be used for the production of tradition ceramics.As a result resource shortage is becoming more and more serious.Granite is a common mineral,and its reserves are abundant in our country,from the chemical composition aspect.Granite can be use to preparation building ceramics instead of clay.Granite is rich in quartz and feldspar which are barren materials,it is difficult for body molding during the producing process.To achieve in-suit consolidation forming of green body,the gelling network formed by carrageenan dissolved in hot water and solution gel in cool water.we innovatively introduced the in-situ solidification molding method into the production of traditional architectural ceramic.The thesis innovation use granite waste as the main raw material,bauxite as auxiliary raw material,earrageenan and sesbania gum as gelling agent,low molecular polyacrylate sodium as dispersing agent.discuss green body performance through the main influence factor as material's formula?different kind of gel and their proportion,gel content.Preparation technology,The experiment results show that green strength up to 1.5 MPa,drying shrinkage 5%?9%,flexural strength 44?60 MPa,firing range of 1140??1180?,bibulous rate is less than 0.5%.It is the first time using carrageenan and sesbania gum in traditional architectural ceramic.When carrageenan added 2.7%,green strength is 1.2 MPa,When the sesbania gum and carrageenan added the same amount.and total amount was 2.2%,green strength is 1.3 MPa,When carrageenan 1.3g and 0.4g sesbania gum,the green strength is 1.5 MPa,which achieve current dry pressing molding green strength standard.When the solid content is equal,Different concentration of carrageenan slurry has different gel temperature,as carrageenan concentration less than 1.4%,slurry gel temperature is 50? When carrageenan concentration between 1.4%?2.4%,slurry gel temperature is 60 C.Slurry solid content and the addition of colloid have a great influence on green body.Usually,the more solid content the more dense green body the less drying shrinkage.But an excess of solid content will increase the viscosity of slurry that make uneven distribution of body composition,it is a negative factor of green strength.The results showed that the green strength increase with the rising of colloid content,but too much colloid would cause slurry viscosity increase and the slurry liquidity becomes poor.Using low molecular polyacrylate sodium as dispersant,slurry viscosity decreases firstly,and then increases with the rising of dispersant addition.As low molecular polyacrylate sodiun content is 0.3%,the flow of the slurry performance is best.The organic colloid ruled out since 200oC and to the end of the 900? when heating.Because gel adds volume is small,therefore the degreasing process can skim when heating.The addition of bauxite ean promote the formation of mullite,products flexural strength increase with the rising of bauxite content,when bauxite amount is 15%,the body flexural strength is 60 MPa.Using wastes wet cast molding make architectural ceramic can not only avoid take high-power machine such as the large tonnage press machine and spray drying tower in traditional ceramic manufacturing process,but also can reduce dust pollution and machine noise effectively.Use granite as the main raw material preparation of architectural eeramic can easing clay shortage problem and get a higher economic benefit.