A Cold Experimental Research On The Recirculating Calciner For High Solid-gas Ratio

There are many advantages for recirculating calciner with high solid-gas ratio(HSGR). By the way of centrifugal separation, making the coarse powder external recirculation can be realized develop the advantageous position of recirculating calciner. Based on the point, two different recirculating calciners have been designed, and pressure drop and collection efficiency have been studied under different conditions. Performances of horizontal cyclone and whirl separator, which are component of the recirculating calciner, have been investigated, meanwhile, fractional collection efficiency of horizontal cyclone was analyzed.The results show that under pure gas flow condition, when the cross-section gas velocity of calciner ranges 6.0⁸.0m/s, the pressure drop of horizontal cyclone separator varies in 80²00Pa, and the pressure drop of whirl separator is around 600¹180Pa. The pressure drop for I-recirculating calciner system (calciner and horizontal cyclone separator) is lower than II -recirculating calciner system (calciner and whirl separator) about 300⁶00Pa.Under normal working condition, the collection efficiency for horizontal cyclone separator fluctuates at the range of 31⁴8%, so by changing the operating parameters, the required collection efficiency can be satisfied when keeping with the structure size proportion. Under the conditions that the average diameter of cement raw meal is 24.3 μm and solid-gas ratio (z=0.3⁰.45) is lower, the fractional collection efficiency of the horizontal cyclone separator is gradually increased with increasing raw meal size, and the cut size is all more than 70μm. When the solid-gas ratio is in 0.58¹.59, the cut size d_c50 for the horizontal cyclone separator fluctuates at the range of 40⁷0μm, so coarse powder recirculating has been realized. When the collection efficiency for the whirl separator is less than 30%, II - recirculating calciner system can be operated stablywith relatively lower on the basis of lower recirculating proportion.According to the present research conclusions, primary analysis has been done for material separation and particle retention time for recirculating calciner system.