Application Research Of Copper Tailings In Porous Sintered Products

This subject uses copper tailings as the main raw material,and shale,feldspar,bentonite,and cement as auxiliary raw materials to prepare copper tailings porous sintered products.This article is based on the chemical analysis,mineral analysis,particle size analysis and thermal analysis of the experimental materials,the direct foaming method is used to prepare a copper tailings foam ceramic blank,and an artificial jacking method is used to prepare a copper tailings permeable product blank.By optimizing the composition of the product and the sintering process system,the optimal ratio and process parameters of the product were determined,and the relationship between the composition,structure and performance of the product was studied.The main contents of the study are as follows:?1?Theminerals in the copper tailings are mainly quartz,biotite,serpentine,and soda feldspar,and the oxides are mainly SiO₂,and a small amount of alkali metal oxides assist the flux.Copper tailings and other raw materials have a wide range of particle size distribution.Their-200 mesh particle size accounts formore than 70%.?2?The copper tailings foam ceramic foaming process requires high-temperature stirring and foaming using warm water at about 40?.The copper tailings water-permeable sintered products need to use a steel pin with a diameter of2 mm for artificial insertion when the body has a certain strength.?3?In the preparation of copper tailings foam ceramic body,when the ratio of copper tailings:cement:shale:feldspar:bentonite is 55:15:15:10:5,and the foam is added at 400%of the slurry volume the strength is best.Body strength reaches0.291 MPa,dry shrinkage is 6.91%.In the preparation of copper tailings permeable product body,when copper tailings:shale:feldspar ratio is 62.5:35:2.5,the strength of the body is 1.17 MPa,and the dry shrinkage is 3.12%.?4?The strength of copper tailings porous sintered products increases with the increase of the maximum firing temperature,increases with the increase of the holding time,and decreases with the rise of the heating rate,but the sintering temperature of the foam ceramics should not exceed 1120?.The sintering system of copper tailings foam ceramics is best heated to 1120?at a heating rate of2.5?/min and maintained for 120min;the sintering system of copper tailings permeable sintered products is best heated at a heating rate of 5.5?/min to 1120?for 120 min.?5?Through thermal analysis of other raw materials such as copper tailings,set up segmented sintering and maintain heat at special temperature points.The optimized sintering system is:sinter from room temperature to 200?at a temperature of 6?/min for 30minutes,sintering at a rate of 3.3?/min from 200?to 500?,sintering at a rate of 4?/min from 500?to 700?and holding for60 min,and sintering at a rate of 5?/min from 700?to 1120?for 120 min.What is the strength of the foamed ceramics produced is 1.26 MPa,the firing shrinkage is14.16%,the porosity is 56.6%,the water absorption is 16.5%,and the density is0.463 g/cm³,and the thermal conductivity is 0.11 W/?m·K?.The compressive strength of the obtained water-permeable sintered product was 37.3 MPa,and the flexural strength was 3.78 MPa.