The Research On The Anti-coking Technology Of The Burner In 670T/H Boiler

This paper put forward a method to improve the boiler by adding side-secondary air (SSA) to the primary air (PA) , dealing with the ubiquitous coke phenomenon of the 670T/H boiler in the thermoelectricity factory of DaQing oil fields and the lignite boiler in northeast area of China.In order to find out the best solution, the cold model experiments were carried out using the test bed existed. The average velocity of the wind field near the primary air exit and hearth wall area during a certain period was tested with 2-dimentional Hot Wire Anemometer under different working condition. The influence of the momentum of primary air, the momentum of side-secondary air and the ratio of height to width of the primary air to the PA jet rigidity with SSA were analyzed.The alteration solution to the 670T/H boiler was established and carried out based on the results of cold model experiments. And the cold air dynamics experiments were also carried out. The rule of the airflow was found, and thus provided the reference for the heat state running of the boiler. In order to improve the burning, the pulverized coal concentrator and the pulverized coal allocator baffle were adjusted to decrease the wind speed difference between the thick dense and the thin side of the same PA jet, and also different layers of PA jets. The feasibility of the alteration solution was proved through the air dynamical field experiment.After the cold model experiment, the 670T/H boiler in the thermoelectricity factory of DaQing oil fields was started. The parameters correspond were compared with which before the alteration, and educed the following conclusion: The coke phenomenon was settled successfully, and the burning efficiency of the boiler was improved. All these proved that the alteration of the four corners of a tangentially fired furnace come to a success.