Research On Preparation And Property Of Tungsten Tailings Aerated Concrete

Beneficiation would produce the accumulation of tungsten tailings, not only takes up a lot of land resources, but also pollutes the environment. The amount of tungsten mine in Jiangxi is a quarter of that in the whole nation. And at present the development and utilization of tungsten tailings is less. There fore, strengthening the cyclic utilization of the tungsten tailings and promoting the recycling of tungsten tailings, such as developing the application of that in construction wall materials, would promote the coordinating development of mine enterprise’s economic benefit, social benefit and environmental benefit.This text uses some tungsten tailing from Ganzhou, studies the chemical composition, mineral composition and activation index of that, and studies the basic physical properties,frostresistance,water resistance,anti-carbonation and of autoclaved microtructure aerated concrete.By studying we know that there are a lot of active SiO2in the tungsten tailings. After levigation,through the experimental analysis of activation index,we find that,the activation index of tungsten tailings glue sand specimens with thirty percents of tungsten tailing after28days comes to70%; and that with forty percents of tungsten tailing comes to60%.By the active admixture experiments, we find that putting early strength agent and alkali-activator into tungsten tailings can make the activation of tungsten tailings be further improved, especially have great impact on the improvement of the early strength. By adding active admixtures, we can change the property of tungsten tailings to improve the later strength.By the orthogonal design experimental analysis on the impact of raw materials on the property of aerated concrete,we initially determine the initial mix proportion of aerated concrete,and then by further optimal design,we get the percentage of various raw materials which are to be maken into tungsten tailing aerated concrete.The percentage of cement is10%to20, lime18%to20%, gypsum4%, aluminum powder0.08%to0.14%, and ratio of water to material0.55to0.6. The made-up aerated concrete of B06-level and B07-level wth optimized mix proportion has good frost resistance and water resistance.Maintained in room temperature condition, the hydration product’s crystallized degree of tungsten tailing aerated concrete is low, and produce CSH (B) with much gel and weak crystallization, These hydration products reduce the strength of products.However, in autoclaved environment, the generated tobermorite stones penetrate each other and combine closely to result in improving the strength of products. In freezed environment, the internal structure of products is destroyed, the bonding force of tobermorite stones is poor,and the strength of products is reduced.