Low nitrogen formation mechanism and furnace pressure control during combustion

The formation mechanism of NOx

The primary air is mixed with the gas, ignited and ejected, and the secondary high-speed airflow coils the surrounding furnace gas back flow, so that the oxygen concentration in the flame combustion area is reduced, and the oxygen concentration of 2% ~ 15% is obtained, forming oxygen-poor combustion, and the production of NO is reduced.

Air passes into the combustion area twice, so that the whole combustion process is divided into two stages, avoiding excessive concentration of high temperature area, and the temperature field in the furnace is more uniform. In high temperature regenerative combustion system, smoke and air switch device is needed, thus reversing valve is the key equipment of the system if the by pass valve, the system has a pair of high temperature regenerative combustion devices will need 4 sets of switch valve, and USES the directional control valve, the system in high temperature regenerative combustion device is only need a switch valve, cost can be greatly, reduce the reversing control in general is given priority to with when reversing, but when overtemperature exhaust system must have at the same time to enforce the function of reversing reversing valve commutation time by time and temperature of master-slave control, i.e., according to the timing, but at the same time, when the regenerator flue gas temperature more than set set, The control system will automatically alarm and control the reversing valve to force reversing according to the temperature signal.

the furnace pressure control in the combustion process

In the process of periodic switching of combustion/exhaust in regenerative combustion system, the furnace pressure will also change periodically, but the change of furnace pressure will obviously lag behind the switching of combustion system. The disturbance to the control system during periodic reversing is the difference between regenerative furnace and conventional furnace. But due to the interference is foreseeable interference, control system in the automatic control mode, the system can be used "shock" the method of interference filter system, to stabilize the combustion and to prevent the cold wind, absorption system should be set inside the furnace pressure in the 0 to 50 pa micro positive pressure condition, the computer system should be able to control the adjustment of the machine top butterfly valve opening automatically track the set value, guarantee within the scope of furnace pressure has been set.