| China is rich in tungsten resources,although the tungsten smelting industry started relatively late,but after decades of development,China's tungsten smelting technology has been ranked the world's leading level.At present,the mainstream decomposition of tungsten ore in tungsten smelting industry is sodium hydroxide decomposition method.In order to avoid the "calcium returning " chemical reaction which could lead to low leaching rate.Phosphoric acid or sodium phosphate was added in industrial decomposition of tungsten ore.The operation is also applicable to tungsten smelting factory whose major raw material is wolframite-scheelite mixed ore which is common in the Southern region of Ganzhou district.Compared with other methods of decomposing wolframite-scheelite mixed ore.The operation has the characteristics of small amount of sodium hydroxide and high leaching rate.However,when applied into actual production,sometimes the leaching solution contains high concentration of phosphorus.thus additional phosphorus removal process is needed to ensure phosphorus content in product APT could reach the standard-ed level,Thereby additional production cost caused.In order to perfect deficiencies in actual operation,improve the utilization rate of phosphoric acid in the leaching process,control the concentration of phosphorus in the leaching solution.Based on the program corded using Matlab for ore-matching,special kinds of wolframite-scheelite mixed ore were matched to investigate The effects of major components on the leaching rate of tungsten and the utilization rate of phosphoric acid.A system especially for wolframite-scheelite mixed ore matching process was developed using the experimental results as objective function algorithm.The main contents and results are summarized as follows:(1)As to the fact that the content and ratio of the major components in the wolframite-scheelite mixed ore prepared by the traditional method of ore-matching remained changed frequently.A program corded using Matlab targeted ore-matching process for wolframite-scheelite mixed ore was developed,ore preparation could accurately achieved by the program,and used in experiments to explore the effect of major components on the leaching rate of tungsten and the utilization rate of phosphoric acid.(2)Using the program corded for ore-matching with reference to factory's best technological conditions(liquid solid ratio of 2:1;the amount of phosphoric acid is equal to the theoretical amount;the amount of sodium hydroxide is 1.66 times of the theoretical amount;the reaction temperature of 140 degrees;the holding time of 3h;The stirring speed of 350r/min)to investigate the effects of changes in three major components content in wolframite-scheelite mixed ore: calcium;tungsten trioxide;calcium in the form of calcium tungstate on the leaching rate of tungsten and the utilization rate of phosphoric acid.Experimental results show: with the increase of the percentage of calcium content in the mixed ore.The leaching rate and the utilization ratio of phosphoric acid were gradually increased,and the phosphorus concentration in the leaching solution was gradually increased also;with a increasing percentage of tungsten trioxide content in the mixed ore,the leaching rate and the utilization ratio of phosphoric acid were gradually increased,however the phosphorus concentration in the leaching solution was gradually decreased;with a increased percentage of calcium content in the form of calcium tungstate in the mixed ore,The utilization ratio of phosphoric acid was decreased,and the phosphorus concentration in the leaching solution was increased also,but leaching rate remained almost unchanged.(3)Results of experiments investigating the effects of changes in three major components content in wolframite-scheelite mixed ore: calcium;tungsten trioxide;calcium in the form of calcium tungstate on the leaching rate of tungsten and the utilization rate of phosphoric acid were used as the basis of the system objective function algorithm for the development of Optimized ore-matching system.The system consists of tungsten ore information storage and import module,the selection of tungsten ore module,methods of matching process module,ore distribution results and statistical results output module,menu bar and right-click menu module.tests results shows the system is stable;simple;user-friendly.Compared with the traditional ore matching method,The system is more accurate and fast.meanwhile,can stabilize tungsten leaching rate and control phosphorus concentration in leaching solution,improve the utilization of phosphoric acid,remove the special existing phosphorus removal process,reduce tungsten smelting cost. |
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