SIMULATION OF GAS FLOW FIELD AND PRESSURE FIELD IN HIGH PELLET RATIO FURNACE SMELTING
In blast furnace production and smelting,increasing the proportion of pellet ore can bring many benefits,such as uniform particle size,lower SiO2 content than sintered ore,favorable indirect reduction,and reduced coke and fuel ratios.However,this will also lead to a decrease in the permeability of the melt zone,an increase in the pressure difference of the blast furnace,and at the same time suppress the development of the central gas flow,affecting the distribution of gas flow.This article uses numerical simulation methods to study the changes in gas flow field and pressure field in a 3 600 m3 blast furnace when increasing the proportion of pellets.The research results show that when the proportion of pellets increases from 31％to 60％,the total pressure difference of the blast furnace increases by 9.45 kPa.Among them,the high ball ratio promotes an increase in the porosity of the block shaped zone,reducing the pressure difference between the upper and middle parts,while the resistance of the soft melt zone to gas flow increases,resulting in a significant increase in the pressure difference at the lower part,and the increase exceeds the sum of the pressure difference decreases at the middle and upper parts.At the same time,the overall gas flow velocity was suppressed,with a decrease of 0.16 m/s in the gas flow velocity of the material layer and 0.32 m/s in the central gas flow velocity.The gas flow velocity in the coke window area of the soft melt zone decreased even more,at 0.63 m/s.In addition,if the proportion of pellet ore is increased while maintaining the same pressure difference,it is necessary to reduce the incoming air flow by 268 m3/min,lower the pressure in the lower part of the blast furnace,but further suppress the central gas flow;Or optimize the raw material conditions,adjust the fabric system,and increase the porosity of the block belt from 0.329 to 0.337.At this time,the gas flow rate still decreases,but the gas flow distribution in the block belt layer is improved.
numerical simulationhigh pellet ratiogas flowpressure fieldvelocity field
万方数据
维普
