Design And Performance Analysis Of Steam-assisted Flare Burner

The torch system is an important safety and environmental protection facility of the refinery.Its function is to burn the flare gas containing various organic substances such as hydrocarbons and hydrogen sulfide in start-stop,abnormal working conditions and accident conditions.However,during the combustion process,the flare gas often cannot be completely burned,and the torch emits black smoke frequently.At present,measures to inject high-pressure steam into the torch head(the device in which the flare system is responsible for burning the flare gas)are mainly used to reduce black smoke and improve the burn-up rate.The ejector in the torch head is the main structure for jetting steam.The device enables the entrainment of air near the torch head: having the ability to ignite air.The stronger the ejector's ability to ignite,the less water vapor can ignite more air,which can reduce the amount of steam,save costs,and promote the combustion of the flare gas more fully,so the ability of the steam ejector to ignite the air has a decisive influence on the processing capacity of the flare head.Based on this,this paper mainly carries out the following work:(1)Design a new type of torch head that can achieve split combustion and central combustion support.By improving its structure parameters,the injection coefficient of the steam head of the flare head is improved,and the combustion efficiency of the flare gas is improved.(2)By establishing the steam ejector simulation model,the influence of the ejector spacing,throat diameter,cone angle and other structural parameters on the ejector coefficient is analyzed by Fluent software.The linear regression algorithm is used to comprehensively improve the parameters such as the distance between the nozzle of the ejector and the venturi,the cone angle and the diameter of the throat.The overall structure improvement scheme of the ejector is obtained,and the coefficient of the ejector is increased.(3)The flaming combustion module is used to simulate the combustion of the torch head,and the concentration of the reactants,the concentration of the product and the concentration of the pollutants are analyzed.The designed torch head can meet the national VOC environmental protection requirements.(4)The particle analyzer(PDPA)build an experimental platform.Through the experimental data,the effects of spacing,cone angle and mixing tube diameter on the ejector coefficient are analyzed.The simulation and experimental results are consistent,and the simulation method proposed in this paper is verified.The improved steam injection device can meet the requirements of the torch head performance.The ejector coefficient of the improved flare head reaches 15 or more.Pollutant emissions after flare gas combustion are far below national standards and can meet the requirements of field applications.