Design And Thermal Process Analysis For Vertical Reduction Furnace Of Laterite Nickel Ore

Currently,the increasingly reduced resources of nickel sulfide ore cannot meet the demand of countries from all over the world on nickel-iron,nickel oxide ore with poor nickel enrichment but abundant and convenient for mining gradually becomes the main raw material of nickel-iron alloy,current nickel-iron treatment process has issues of high consumption and complicated process when facing low presence of nickel oxide ore,it is the inevitable choice to develop a low pollution,low energy consumption,adaptable nickel oxide ore processing.Analysis of existing process,hydrometallurgical Ferro-nickel process common exists the problems of the treatment of wastewater,serious pollution and so on.From the point of investment and mature technology,Pyro metallurgical Ferro-nickel process occupies a leading position.And the most widely used RKEF method has the problem of each lower 0.1%nickel content increasing the energy consumption by 3%to 4%,CO recovery process and gas treatment equipment complexity.Based on the original process,we propose a new type of nickel-iron smelting process.The key elements are:First,a new type vertical ferronickel smelting reduction furnace processing is designed.The process used the methods of Da Jiangshan and magnesium reduction tank as a reaction vessel for reference,then pressed nickel ore and coal ball together into the tank,heating and reducing directly,making exhaust gas generated by smelting as a fuel secondary flow,finally ended the process and the smelting product needed the following steps of water quenching,magnetic separation and refining.This process has the advantages of direct and efficient use of CO and dry distillation gas,simple equipment,the use of storage technology and so on.Second,regard the cavity between the outside surface of the tank and the restore surface as the reaction field,use simulation software fluent to study the problems of complex combustion,flow and radiation in the three-dimensional space of furnace.The purpose is to obtain the temperature profile of the surface of the reduction tank as a boundary condition of following simulation inside the pellet.Third,regard the wall of the tank and the internal pellets as the research object,analyze its internal heat transmission process,establish differential equations and derive matrix solution.Provide the combustion simulation results as boundary conditions for reduction process simulation,and get the internal temperature distribution field of the tank after three hours'smelting,then analyze and compare the thermal parameters.Finally,analyze the influence of the different thermal parameters on the melting process,and find that the low material conversion rate is because of the low thermal conductivity of the pellets.The conversion rate of the pellets is 0.87 by the way of using the set of cans.Through the orthogonal test,it is the best smelting process parameters when heating time was 3h,temperature of the wall is 1400,the porosity is 0.45.Under this condition,the conversion rate of the pellets is 0.95.