Structure And Property Of Light-weight Materials Prepared From Insulators Waste

Ceramics insulators which were widely used for power transportation had graduallybecome an important source of solid waste. Large amount of ceramic insulators wastemade from feldspar, clay and quart couldn’t be recycled which caused waste of resources.In this paper, insulators waste were used as a cheap raw material for the preparation oflight-weight materials in order to take advantage of SiO2and Al2O3component effectivelyand provide low cost porous aggregates for light-weight castable.Based on thermal calculations, effects of firing temperature and content of insulatorswaste on the preparation of light-weight materials were investigated. The main contents inthis paper include three parts.(1) Influence of firing temperature, content of clay, particlesize and kinds of porogen on the properties of light-weight mullite bricks wereinvestigated while high-voltage insulators waste (HVIW) were used as main materials.(2)Influence of firing temperature, insulators waste content, kinds of porogen on theproperties and microstructures of light-weight aggregates were studied. In this part, HVIWand low-voltage insulators waste (LVIW) were used as main materials for two kinds oflight-weight aggregates.(3) Effects of different aggregates on the strength of light-weightcastables were studied. The detailed results were listed as follows:(1) Light-weight mullite bricks from HVIW, with the better comprehensive properties,bulk density1.14g/cm3, apparent porosity61%, cold crushing strength (CCS)3.5MPa，thermal conductivity0.223W/(m·K) at the testing temperature300oC, as the content ofclay is20wt.%, the firing temperature is1400oC.(2) Light-weight aggregates from LVIW, with the better comprehensive properties,bulk density1.10g/cm3, apparent porosity56.6%, compressive strength35.3N, as thecontent of LVIW is60wt.%, the firing temperature is1200oC.Light-weight aggregates from HVIW, with the better comprehensive properties,bulk density0.96g/cm3, apparent porosity65.8%, CCS42.1N, as the content of HVIW is70wt.%, the extra addition of porogen is1000mL/kg, and the firing temperature is1400oC.(3) Both cold modulus of rupture (CMOR) and CCS of LVIW castables dried at110oC×24h increased as the content of LVIW in aggregates increasing. LVIW castables got the better strength as aggregate was DA70. Both CMOR and CCS of HVIW castablesincreased as the firing increasing or the addition of porogen in aggregates decreasing.Matrix of HVIW castables combined with aggregates more closer while aggregate wasHA-2and the firing temperature is1400oC, contributing to the better properties of HVIWcastables.