900t/d高热值垃圾焚烧炉污泥掺烧数值模拟

Numerical Simulation of Co-combustion of Sludge in a 900t/d Waste Incinerator

本文针对某台900 t/d高热值垃圾焚烧炉焚烧城市生活垃圾和掺烧生活污泥进行了数值模拟,研究了掺烧污泥含量、污泥含水率对炉内燃烧、流场及烟气主要组分分布及污染物排放特性的影响。结果表明:在相同工况下燃烧城市生活垃圾,烟气温度和污染物浓度的模拟结果与现场数据相符合。随着污泥掺烧量的增加,炉排固相燃烧过程延迟,水分蒸发速率增大,温度下降,挥发分析出速率降低约70 kg/(m^2·h),焦炭燃烧速率下降约10 kg/(m^2·h),污染物NO_x排放增加50.98 mg/m^3。随着污泥含水率的增加,温度降低约25 K,污染物NO_x排放降低.掺烧污泥对炉内速度矢量场影响较小。该数值模拟结果可为垃圾焚烧发电厂提供掺烧污泥的可行性建议与掺烧方案。

Numerical simulation was carried out on a 900 t/d high-calorific-value waste incinerator for co-incineration of municipal waste and domestic sludge.The effects of mixing quantity and the moisture content of sludge on the combustion characteristic and flow field in the furnace were studied.The distributions of the main components of the flue gas and pollutant discharge characteristics are researched as well.Under the identical working conditions,the simulation results about flue gas temperature and pollutant concentration of burning municipal solid waste are consistent with the actual field data.As the amount of sludge blending increases,the solid phase combustion process of the grate is delayed,and the water evaporation rate increases.Meanwhile,the temperature decreases,and the volatilization analysis rate decreases by 70 kg/(m^2·h) approximately.The coke burning rate decreases by 10 kg/(m^2·h) approximately,pollutant NO_x emissions increased by 50.98 mg/m^3.With the increase of moisture content of the sludge,the temperature decreases by about 25 K,and the NO_x emission decreases.The mixed sludge has little impact on the velocity vector field in the furnace.The numerical simulation results can provide feasible suggestions and burning schemes for municipal solid waste power plants.