WANG Aihua
,
CAI Jiuju
,
LI Xiuping
,
WANG Ding
,
ZHOU Qingan
钢铁研究学报(英文版)
To change the undesirable present situation of recovering and using converter gas in steel plants in China, the basic approaches to improving the converter gas recovery rate were analyzed theoretically along with the change curves of the converter gas component content, based on the converter gas recovery system of Baosteel No2 steelmaking plant. The effects of converter device, raw material, air imbibed quantity, recovery restricted condition, and intensity of oxygen blowing on the converter gas recovery rate were studied. Among these, the effects of the air imbibed quantity, recovery restricted condition, and intensity of oxygen blowing are remarkable. Comprehensive measures were put forward for improving the converter gas recovery from the point of devices, etc, and good results were achieved.
关键词:
steel plant;converter gas;recovery rate;affecting factor
WANG Aihua
,
CAI Jiuju
,
XIE Guowei
钢铁研究学报(英文版)
The influences of air preheating temperature, oxygen concentration, and fuel inlet temperature on flame properties, and NOx formation and emission in the furnace were studied with numerical simulation. The turbulence behavior was modeled using the standard kε model with wall function, and radiation was handled using discrete ordinate radiation model. The PDF (probability density function)/mixture fraction combustion model was used to simulate the propane combustion. Additionally, computations of NOx formation rates and NOx concentration were carried out using a postprocessor on the basis of previously calculated velocities, turbulence, temperature, and chemical composition fields. The results showed that high temperature air combustion (HiTAC) is spread over a much larger volume than traditional combustion, flame volume increases with a reduction of oxygen concentration, and this trend is clearer if oxygen concentration in the preheated air is below 10%. The temperature profile becomes more uniform when oxygen concentration in preheated air decreases, especially at low oxygen levels. Increase in fuel inlet temperature lessens the mixing of the fuel and air in primary combustion zone, creates more uniform distribution of reactants inside the flame, decreases the maximum temperature in furnace, and reduces NOx emission greatly.
关键词:
high temperature air combustion;flame property;temperature distribution;NOx formation;NOx emission
