循环流化床中石油焦与煤混合燃烧温度场研究

A Study of the Temperature Profile Resulting from the Mixed Combustion of Petroleum Coke and Coal in a Circulating Fluidized Bed

石油焦是炼油工艺的副产品 ,具有低灰分、一定挥发份和高热值的特性。焦中含有相当多的硫、氮元素和钒、镍等碱金属元素 ,这些成分在石油焦燃烧时可造成锅炉内腐蚀和沾污。经过技术对比认为 :利用循环流化床燃烧技术将石油焦与煤混合燃烧是高效、清洁回收利用石油焦的有效方法。本文在热输入率为 0 .5MW的循环流化床热态试验装置上进行了石油焦与煤掺混燃烧炉内温度场研究 ,分析了石油焦与煤不同燃料配比 ,不同锅炉运行参数 ,如一次风率、过量空气系数、Ca/S比和给料量等对炉内温度场分布的影响规律。

As a byproduct of crude refining process petroleum coke features a low ash content, moderate volatility and a high heating value. It contains a sizable quantity of metallic elements, such as vanadium and nickel as well as sulfur and nitrogen. During the combustion of petroleum coke these elements can cause in-boiler corrosion and fouling. After a technical study it is found that the mixed combustion of petroleum coke and coal in a circulating fluidized bed represents an effective and environment-friendly approach for the utilization of and heat recovery from the petroleum coke. To verify the above fact a study concerning the temperature profile obtained in the course of mixed combustion of petroleum coke and coal was performed on a circulating fluidized bed hot-state test rig with a heat input of 0.5 MW. The impact of various factors and parameters on the temperature profile in a boiler furnace was investigated. They include the different blending ratios of petroleum coke and coal, different boiler operating parameters, such as primary-air flow rate, excess air factor, Ca S ratio and coal feed rate, etc.