The Research Of Compound Air Stage Combustion Technology Application On Tower Type Boiler

As China relies on coal as its major energy resource,coal-fired generating units will continue dominating in China's overall power supply structure.For the reason that people pay growing attention to the sustainable development of energy and environment,large-capacity ultra-supercritical tower boilers take an increasing significant position in the field of thermal power generation for its energy efficiency and low emission.This thesis takes ultra-supercritical tower pulverized-coal fired boiler as the main object of study,aiming to provide some references for the development of combustion system of ultra-supercritical tower pulverized-coal fired boiler.A modification scheme of a certain 1000 MW tower boiler was proposed by analyzing the running condition of its combustion system.Then the modification effect was analyzed with the data of performance evaluation test.A superior compound air stage combustion designing scheme was put forward based on the experience of the modification.And this advanced compound air stage combustion designing scheme was applied to a new 1200 MW tower boiler.Using a commercial software,the flow field,heat transfer,combustion process and process of NOx production in this 1200 MW pulverized-coal fired boiler was investigated numerically.The research results show that: With the application of the advanced compound air stage combustion technology,tower type boiler's furnace shows good aerodynamic field and combustion temperature field and flue gas temperature deviation is decreased.In addition,the furnace shows good ingredient distribution field and guarantees the combustion stability and burn-out rate.Furthermore,the application effectively reduces the NOx emissions during pulverized-coal combustion.