| Gas-solid fluidized bed has very extensive application because of its good isothermal characteristics and can improves the contact and transmission between the fluid and particles,after years of development,the research direction and content of gas-solid fluidized bed are becoming more and more.But at present,domestic and foreign researchers mainly focus on the dry particle system on the study of particle flow characteristics in the fluidized bed,in the actual production process,the chemical reaction of gas-solid particles in the fluidized bed will inevitably produce liquid components or add liquid components for the process.The domestic low-temperature chlorination technology is being continuously studied and mature,but the reaction between chlorine gas and TiC in this process is very violent and will give off a lot of reaction heat,so effective means of temperature control are needed to take the heat out.At present,the most effective method to take heat is returning mud,the previous research results show that there is a strong correlation between the amount of returning mud and the slagging of the chlorination furnace,excessive amount of mud or too fast rate of returning mud may cause the slagging of the chlorination furnace.This topic takes the low temperature chlorination process of titanium-bearing slag as the research background.and take the chlorination furnace produced in a pilot plant as an example to establish an experimental system for simulating the gas-solid flow in a chlorination furnace.The fluidization parameters of carbonized slag and its substitute powder were analyzed by using the Mastersizer 2000 laser particle size analyzer and choose the rutile for the simulation experiment which has the similar fluidization characteristics to carbonized slag.It has a Experimental research on the the main operating parameters Including the bottom fluidization speed,the height of the material layer and feeding speed which is affecting gas-solid flow mixture and get the optimal range of bottom fluidized gas flow is 12m~3/h?16m~3/h,the optimal layer height is475mm,and the optimal feeding speed is 361.2kg/h.On this basis,it is studied the influence of the added wet component on the gas-solid flow state in the furnace,and the optimum gun height was 450mm.A computer numerical simulation model was established to simulate the interaction process of gas-solid two-phase flow in the furnace.By comparing and analyzing the flow state,particle concentration distribution and bed pressure drop obtained by extraction and simulation calculation with corresponding physical model experiment,it shows that the simulation calculation can better describe the actual flow process and parameter change characteristics in the furnace,and the simulation calculation is feasible.Then adding wet components to simulate and considering the influence of residual liquid phase quantity in the furnace on the gas-solid flow under the condition of adding wet components and analyze the influence of the flow state,pressure change and component concentration in the furnace under different fluidization velocity,wet component location,wet set of components(liquid-solid ratio?)and bed height,the results are as follows,(1)the pressure distribution and concentration distribution in the bed are relatively uniform when the fluidized gas velocity is 14m~3/h?16m~3/h;(2)the position(insertion depth),liquid-solid ratio and height of material layer of the wet component spray gun have obvious influence on the pressure and concentration distribution in the furnace.The reasonable insertion depth of the wet component spray gun position is 300mm?450mm,the reasonable liquid-solid ratio is 0.001-0.005.The recommended bed height range is 475mm?525mm. |
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