First, the basic principle The NaF leaching method reacts as follows: At 225 ° C, the concentration equilibrium constant is 24.5. The leaching rate of tungsten than white with CO 3 2 - -, PO 4 3 - other large (see FIG. 1) F. Figure 1 Reaction rate of CaWO4 with different anions (PB Kui) At less than 100 ° C, a CaF 2 film is formed on the surface of the ore particles, which hinders the reaction. Above 100 ° C, the film falls off. The apparent activation energies were 63.54 kJ∕mol and 89.03 kJ∕mol, respectively, at stirring speeds of 830 r∕min and 510 r∕min, respectively. Second, the main technical indicators When a Russian scholar treats a white tungsten ore containing 33.7% to 41.5% WO 3 , when the temperature is 225 ° C and the amount of NaF is 1.8 times the theoretical amount, the decomposition rate is 99.2% to 99.8%, and SiO 2 ∕ WO 3 = in the leachate. 0.2% to 0.5%. Yao Zhengang waited for the treatment of Shizhuyuan white tungsten concentrate under industrial conditions. When the amount of NaF was 1.2 times the theoretical amount and 1.5 hours at 190 °C, the decomposition rate was 98.87%, and the obtained Na 2 WO 4 solution contained P0.002g. L, As 0.017 g ∕ L, SiO 2 0.055 g ∕ L. The disadvantage of the NaF leaching method is that the solubility of NaF is limited, that is, the F - concentration in the leaching agent is limited, and accordingly the unit production capacity is low. Gildemeister CNC Lathe for Metal is one type of CNC Lathe Machine which designed mainly to do milling ,drilling and taping work on round metal material to make small spare parts or components for machine .Machine has professional control system as well as fixing device ,use special cutting tools drove by servo motors for a high accurate cutting work .The CNC Lathe for Metal machine is used for the industry such as Automotive ,Vessel,aircraft,Rail transit ,Energy ,chemical machinery ,Electrical appliance etc . Cnc Machine Turning Lathe Metal,Cnc Metal Lathe Machine,Cnc Metal Turning Lathe,Cnc Machined Parts Metal Jinan Rapid CNC Machinery Co.,LTD , https://www.gildemeistercnc.com