Application Of Solid Waste In Shale Sintered Brick

Make full use of solid waste is the concept of circular economy,which can reasonably protect plowland and mineral resources.It coincides the sustainable development of wall materials,building a conservation-oriented society.This paper aims to make solid waste into shale sintered brick,developing effective energy.It provides technical support for national circular economy and energy conservation.The influence of agent on properties of shale brick was investigated.Analyzing the mineral and chemical components of titanium slag,CFBC fly ash and chromium slag, the main components were Si O2,Al2O3,Fe2O3,Ca O,Mg O.Titanium slag contained perovskite and diopside.CFBC fly ash contained silica,hematite and gypsum.Chromium slag contained periclase,brownmillerite and chromium oxide. Analysis of the thermal properties of the three solid wastes,they can lost adsorbed water and crystal water in low temperature.There were chemical reactions in high temperature with endothermic,heat and mass change.Titanium slag, CFBC fly ash and chromium slag had chemical reactions completely in 1000℃,900 and 900℃ ℃,which were initial sintering temperatures to make shale bricks.Solid waste and shale made sintered brick,which tested properties of compressive strength,firing linear shrinkage,water absorption and bulk density.Studies have shown that titanium slag was 20%,compressive strength of 30 MPa fitting the national standard. It could be appropriate to increase content of the titanium slag,using resources sufficiently.The 1000 ℃sintering temperature and 2h holding time were optimum preparation conditions.Compressive strength of 15% CFBC fly ash was 10.55 MPa,fitting the minimum strength 10 MPa.Compressive strength of 20% CFBC fly ash was 6.05 MPa,so it was up to 15% in shale.The 1100 sintering temperature and 2h ℃holding time were suitable heating program.Compressive strength of 20% chromium slag was 10.67 MPa,which could not add content,but the suitable content was 7%.Sintering temperature was between 900 ℃and 1000℃,and optimum holding time was 4h. Sintered products for micro-analysis, the main crystalline phases of titanium slag-shale brick were quartz,anorthite,akermanite and diopside.CFBC fly ash-shale brick were quartz and anorthite.The main crystalline phases of chromium slag-shale brick were different at diverse chromium slag contents and sintering temperatures,but they included quartz.Through leaching toxicity experiments,the concentrations of leaching of heavy metals were analyzed with solid waste and shale making sintered brick.Concentrations of Ba,Cr,Cu,Ni,Pb,Zn,As,Cd and Co in the leachates were measured,the contents of titanium slag and CFBC fly ash in accordance with national standards,environmentally and safely.When chromium slag added 10%,15% and 20%,concentrations of Cr was higher than standard.However,maximum content of chromium slag was 7%,and the concentrations of heavy metals in the leachates of sintered bricks were less than theoretical concentrations.