Experimental Technology And Performance Characterization Of Lightweight Foam Glass Based On Coal Waste

The preparation of foam glass not only makes full use of waste glass,but also can incorporate fly ash to enhance the strength of foam glass and alleviate the increasingly serious dust pollution.Foam glass has small density,low thermal conductivity,sound absorption,non-flammable,good chemical stability,anti-freeze performance and other excellent properties.Therefore,it is of great significance to use waste glass and fly ash to produce foam glass reasonably and effectively.In this paper,fly ash and waste flat glass are used as the main raw materials,and foam glass is prepared by molding sintering method.Firstly,the influence of the type of foaming agent on the properties and structure of foam glass was studied to determine the optimum foaming agent type.The main factors affecting the performance of the foam glass and the appropriate ratio and proeess are obtained by single factor test and orthogonal test.The physical properties such as bulk density,average pore diameter,compressive strength and porosity of foam glass were tested and their pore structure was characterized.The specific research contents and test results are as follows:(1)The foam glass was prepared by using calcium carbonate,silicon carbide and carbon powder as foaming agents respectively.The results show that when silicon carbide as foaming agent,the prepared foam glass has smaller average pore diameter,lower bulk density and small thermal conductivity,but poor mechanical properties.When the carbon powder is used as a foaming agent,the prepared foam glass has less open pores.The mechanical properties are good,but the thermal conductivity is high.Considering various physical performance indexes,calcium carbonate is used as foaming agent,and when the content is from 1%to 3%,foam glass with uniform pore distribution,high porosity,excellent heat preservation performance and compressive strength can be obtained.(2)The results of single factor test showed that when the content of calcium carbonate was 2%,the performance of foam glass was the best,the porosity was as high as 82.6%,the bulk density was 0.43g/cm3,and the thermal conductivity was 0.053W/(m·K).The addition of fly ash can significantly improve the mechanical properties of foam glass,and at the same time lead to the reduction of porosity.When the fly ash content is 20%,the compressive strength of the foamed glass is 6.8 MPa,the porosity is 78.5%,and the reasonable fly ash content does not exceed 20%.Increasing the foaming temperature or prolonging the holding time,the average pore diameter and porosity of the foam glass increase,but the foaming temperature is too high or the holding time is too long,and it is easy to produce excessively connected pores,causing the surface of the foam glass to collapse and destroy the pores of the foam glass.When the foaming temperature is 875 ?,the performance of the foam glass is the best and reasonable.The holding time should not exceed 50 minutes.(3)The results of multi-index orthogonal test show that different factors have different degrees of influence on different indicators.For the two indexes of porosity and thermal conductivity,the fly ash content has the greatest influence on the index,followed by the foaming agent content,and the foaming temperature and the holding time have the least influence.According to the range analysis and analysis of variance,the best choice was:The foaming agent content is 2%,the fly ash content is 10%,the foaming temperature is 875 ?,and the holding time is 30 min.Figure[45]table[12]references[116]...