Study On The Preparation Of New Thermal Insulation Materials Utilizing Pitchstone By Foaming Method At Room Temperature

Building energy conservation is an important measure to save energy and protect the environment.Inorganic thermal insulation materials are believed to dominate the building industry in the future due to their high fire resistance performance as well as high strength,non-toxic in practical application and low cost of production.The preparation of a new type of inorganic thermal insulation material-pitchstone thermal insulation material by foaming method at room temperature were mainly studied in the thesis.And the effects of liquid-solid ratio,cetyltrimethylammonium bromide?CTAB?content,hydrogen peroxide?H₂O₂?content,rockwool?RW?addition and low-temperature calcination on the thermal conductivity,compressive strength,density and other properties of the sample and the heat transfer process inside the pitchstone thermal insulation board were systematically studied.The main results of this paper are as follows.?1?The pitchstone thermal insulation material of environmental protection and high-performance was prepared by chemical foaming method using pitchstone as the main raw material,water glass as the alkali activator,CTAB as the surfactant,and hydrogen peroxide solution as the foaming agent at room temperature.When the liquid-solid ratio is 1:1,the surfactant is 0.1%,and the foaming agent is 6%,after400?calcination,the thermal conductivity,density and compressive strength of the samples can be engineered in the range of 0.110 g/cm³,0.049 W/?m·K?and 0.206MPa.?2?Several rules are obtained from optimization results:Firstly,the liquid-solid ratio has little effect on the macro performance,porosity and pore diameter of the sample.Secondly,the content of the hydrogen peroxide solution has effects on the average pore diameter,thermal conductivity,compressive strength,density and other properties.Thirdly,CTAB has a great effect on the size,distribution,and structure of pores.Fourthly,adding appropriate content of rock wool will help reduce the thermal conductivity of the sample,but has little effect on the compressive strength and density.Fifthly,the density,thermal conductivity and compressive strength of the sample decrease to different degrees after 400?calcination,and it is more obvious when the hydrogen peroxide content is low.?3?The modified effective dielectric theory,fractal geometry theory,and several other common theoretical models were used to fit the internal heat transfer process of pitchstone thermal insulation material.It was found that the modified effective dielectric theory fits the actual heat transfer process best,followed by the fractal geometry theory,and the other models have different degrees of deviation from the actual heat transfer process,therefore,they are not suitable for the internal heat transfer process of pitchstone thermal insulation materials.