Influence of N₂/CO₂ on deflagration characteristics of CO/H₂

High-concentration CO/H₂ mixture may be formed in the cold hopper area of local boiler. Deflagration would be caused if there are some high temperature cokes droping into the dangerous area. The influence of N₂, CO₂ concentration on lower deflagration limit(LDL)of CO and H₂, deflagration overpressure of CO/H₂ mixture and its propagation velocity were studied. The results indicate that with the added volume concentration of CO₂ rising from 0 to 18%, the LDL of CO rises from 18.3% to 31.0% nearly linearly, and the LDL of H₂ rises from 11.0% to 16.3% with the same regularity. The overpressure of CO/H₂ deflagration peak decreases from 111.8 kPa to 60.4 kPa within the same CO₂ concentration range. The propagation velocity decreases sharply, but it is always higher than 420 m/s. The higher the molar ratio of CO/H₂ is, the weaker the deflagration overpressure is. The inhibiting effect of CO₂ is more powerful than that of N₂ under the same condition.