The Numerical Simulation Of The Distribution Of Temperature Field During Startup In The Pressurized Pulverized Coal Gasifier

Coal gasification technology is an important direction for the development of clean coal technology, in which pressurized dry pulverized coal gasification technology for its high conversion rate and high environmental benefits has been rapid development. Start-up burner is a key equipment in Shell gasifier start process, mainly during the start of the gasifier reaction chamber boost heating will help to enhance the coal response rate after administration of coal, reducing the reaction chamber outlet stream unconverted carbon content, while controlling the powder burner gas range within the design range, so as not to damage the wall surface of the wall brush protective layer. Carried out on the burner starts operating parameters, especially the temperature field simulation study has important implications for the proper understanding and control of the boot process gasifier.In this paper, the physical model based on Shell dry pulverized coal gasifier, and a three dimensional numerical calculation model is established, and combined with field operating parameters input boundary conditions, the numerical simulation of the operating process oxygen speed, outlet pressure, the amount of fuel, and Effect of oxygen oil ratio and other parameters of the reaction chamber temperature field and flow field; outlet temperature simulation of the resulting reaction chamber compared with the actual operating results, deviation of the engineering technology that is acceptable rangeSimulation results show that: under fuel-rich conditions, with the rate of oxygen increases the temperature of the reaction chamber is gradually increased, and with the increase of the fuel mass flow rate of the reaction chamber temperature is gradually lowered; as the reaction chamber outlet pressure increasing the reaction chamber temperature is gradually reduced, which means a boost in heating process, if the ratio of oil to maintain constant oxygen, oxygen must also increase oil. Increasing the temperature of the reaction chamber with oxygen-oil ratio is reduced after the first increase in the vicinity of the equivalent ratio to the highest temperatures. The reaction chamber pressure of a certain change in the spatial position in the lower portion of the burner operating pressure changes by a big margin, but overall is below a given value, which is also illustrated in the lower portion of the burner started turbulent flow strength is relatively large, fluctuations in operating pressure changes the upper portion of the burner is relatively small, the whole is greater than the given value. Overall temperature distribution in the reaction chamber is 0.3 to 1.3 meters or less start the burner temperature is higher in the longitudinal direction(Y-axis) direction on both sides of the nozzle is high, intermediate low; lateral(X-axis) direction is away from the high temperature zone in the burner a certain distance, forming similar angle of inclination of the burner started along a downward sloping temperature change area, which is conducive to investment and coal combustion fire area.