Research On Dope For Paper-Making With Coal Gangue

In recent years, Coal gangue is no longer viewed as the longest industrial solid waste , but as a kind of resources , it has been widely used and studied in chemical engineering,building materials industry,metallurgical industry, light industry and so on. Coal gangue recycling has become the focus of the comprehensive exploitation research. Utilizing the industrial solid waste——coal gangue to produce the dope for making paper, is not only the progress in science and technology , but also an efficient way to improve profit.In this paper, the tests are made to produce dope for making paper——calcined kaolin using the coal gangue in Tangshan coal mine so as to utilize it as a kind of resources comprehensively. The coal gangue is kind of clay minerals, which is typical in Tangshan area and the whole country . In the property the principal non-metal mineral is hard kaolin. Its molecular formula is Al2O3?2SiO2?2H2O and impurity which affects its whiteness is primarily iron mine and organism carbon, therefore eliminating iron from the ore and calcining are two key techniques to produce dope for making paper——calcined kaolin. Through the tests, it is proved that the dope for making paper with SiO2 53.4%,Al2O3 43.46%,Fe2O3 0.48%,TiO2 1.02%,whiteness 87.21%,and granularity -1250 mesh 99%(-2μm89%),can be produced by acid leaching,wet super grinding and calcination. The product is qualified for the standard of national dope of copperplate paper. Based on the tests, the pricinple of acid lixiviation,mechanism of calcination and the influencing factors in above-mentioned processes are analyzed in theory and the acid reaction model of acid lixiviation is set up.According to the test result, some conclusions can be drawn as follows. The tests have proved the possibility of producing the dope for making paper——calcined kaolin and the good stability,repetition and adaptability of the industrial flow process .Not only does the capability of the product attain the standard of national dope of copperplate paper, but also its utilization rate is high.And there is no new solid waste generated in the tests, so the industrial solid waste——coal gangue can be utilized as a kind of resources.