多源石墨固废制备电热建筑板材试验研究

为提高多源石墨固废的利用率和冬季供暖效率,以石墨矿开采废石为骨料,添加不同质量的球形石墨尾料进行电热建筑板材制备试验研究。考察了球形石墨尾料掺量、养护龄期及湿度对电热建筑板材电学性能及力学性能的影响,并通过通电发热试验研究了发热温度及板材稳定性。结果表明：① 球形石墨尾料掺量和养护龄期对电热建筑板材的体积电阻率影响较大,球形石墨尾料掺量9%时出现渗流阈值。② 养护龄期的增加有利于提高电热建筑板材的力学性能,而随着球形石墨尾料掺量的增加,力学强度先提高后降低,存在最优掺量0.8%。③ 球形石墨尾料掺量9%~11%时,电热建筑板材在36 V交流电压下最终发热温度71~109 ℃,长时间升温后电学性质稳定,可为房屋电热建筑板的冬季取暖应用提供技术指标。

Experimental Study on Preparation of Electrothermal Building Plate from Multi-source Graphite Solid Waste

In order to improve the utilization rate of multi source graphite solid waste and heating efficiency in winter.the experimental study on the preparation of electrothermal building plate was carried out by using graphite mining waste rock as aggregate and adding spherical graphite tailings material with different mass.The effects of spherical graphite tailings content,curing age and humidity on the electrical and mechanical properties of electrothermal building plate were investigated.The heating temperature and plate stability were studied by electric heating test.The results showed that:① the volume resistivity of electrothermal building plate is greatly affected by content of spherical graphite tailings and curing age,and the seepage threshold appears when the content of spherical graphite tailings is 9%.② The increase of curing age is beneficial to improve the mechanical properties of electrothermal building plate,but with the increase of spherical graphite tailings content,the mechanical strength increases first and then decreases,and the optimal content is 0.8%.③ When the content of spherical graphite tailings is 9%~11%,the final heating temperature of electrothermal building plate is 71~109 ℃ at 36 V alternating voltage voltage.After long time heating,the electrical properties are stable,which can provide technical indicators for the winter heating application of electrothermal building plate.