Study On Technology Of Alumina And Silica Gel Extraction Of Coal Gangue In Zhungeer Mining Area

Coal gangue is the solid waste discharge in coal mining process, China’s current coalgangue accumulation of about40tons. The coal gangue accumulation not only occupy land,pollute the environment, but also cause the pollution of groundwater and Coal GangueMountain Landslide collapse of geological disasters, a serious threat to human survivalenvironment; in addition, the shortage of bauxite resources in China and the increasingdemand for alumina growing conflict, and coal gangue containing alumina and silicaresources therefore, a lot of, has the important theory significance research on Extraction ofalumina and silica gel technology on coal gangue in this paper, has important practicalsignificance to promote the sustainable development of society.Taking Inner Mongolia coal gangue in Zhungeer mining area as the research object, byelectron probe, chemical analysis and X ray diffraction analysis, chemical composition andmineral composition of coal gangue is determined. On this basis, combined with fractionalstripping method for extraction of alumina and silica gel from coal gangue by acid water, themain process parameters on leaching rate of alumina (including roasting activation, leaching,separation of silica and alumina and auxiliary recovery etc.) are analyzed, and as thefollowing conclusions:1chemical composition of coal gangue is mainly composed of SiO2and Al2O3, contentof more than80%, the main minerals are kaolinite, feldspar, illite and quartz etc..2water acid combined with stepwise leaching basic process steps of alumina and silicagel as the roasting activation, water immersion, water leaching slag clinker leaching, siliconaluminum separation, desalting, pyrolysis and removal of iron, silicon and other links, theprocess flow is simple, low temperature activation, small energy consumption. Through thisprocess can be more than93%of the coal gangue aluminum hydroxide and silica separated.3extracting alumina from coal refuse the best activated agent for sodium hydroxide. Theoptimum parameters of Coal Gangue Activation of coal gangue and sodium hydroxide, theratio of1:1.4, activation temperature of840℃, activation time20min, 4extracting alumina from coal refuse the optimum leaching agent for water andhydrochloric acid. Water acid combined with fractional leaching process using waterimmersion, first after acid leaching. The optimum parameters for the water immersion, waterand sintered clinker solid-liquid ratio1/16, extraction temperature is room temperature,leaching time and optimal parameters for10min; acid leaching, acid concentration,6mol/L,water and acid leaching residue of solid-liquid ratio was1/6, extraction temperature100℃,extraction time30min. Water immersion extraction rate was40.72%, acid leaching, leachingrate of52.65%.5Implementation of recovery and recycling effective than sodium hydroxide, sodiumcarbonate, water, HCl80%raw material can be of the reduce waste emissions process,improve the utilization rate of raw materials, reduces the cost, the development of circulareconomy, saving resources.6Use of the water acid combined method generate1ton alumina extraction from coalgangue, also can generate1.12t silica gel, the profit of1265.6yuan, the total energyconsumption is75.4×10~6KJ, the evaporation water consumption is61.24×10~6KJ, the totalenergy consumption of81.2%.This technique in the comprehensive utilization of coal gangue can be more than80%ofthe components separation of extraction, produce high value-added products, the residue isless than10%of raw coal gangue, does not produce secondary pollution, and can obtain goodeconomic benefit, provides a reliable gangue high value-added use of technology parameter,and has important practical application value.