| The fuel cost recently has been inflated with rise in oil price, and how to make full use of Chinese coal resource instead of oil becomes one focus in industry. To ensure continuable development of energy sources and circumstance in China, the pollution of coal-consumed must be reduced, and moreover, the technology about clean combustion with coal should be developed actively. The realization of effectual and clean combustion with low-pressure hot gas from furnace, whose applied foreground is very wide, can improve economy and protect environment availably. Via having been determined the correlation of flux and press between simulant gas and combustion-supporting air, the pump performance of hot gas combustor is studied without ignition to investigate the characteristic hydrodynamic properties of the coaxial jet combustor and coaxial swirling combustor. The air and gas premixing ability is tested with the burny experimentation about the low-pressure hot gas, and which is compared with the combustion using diesel oil. Besides, numerical analysis is conducted for the turbulent combustion process in finite space out of coaxial jet combustor. --model is adopted to receive distributing and change on press, velocity, turbulent kinetic energy, dissipation rate, temperature and mass fraction etc. of researchful area. Finally, technical flow of substituting gas for oil by calculation is designed, and the feasible blue print is brought forward in the kiln system of detached brick.All the results show that in the experiment without ignition, when simulant gas blower cut off and conduit closed, there is a vacuum on the testing dot of gas pipeline, whose value increases with the elevation of the combustion-supporting air flux, and which can pump low-press gas; as the simulant gas flux is definite, the pump action has relation to air flux only when the air flux exceeds one fixed value.The upmost temperature attains 1050℃ in the combustion experimentation with coaxial jet combustor, which may even be higher when the press and flux of gas is held firmly, it can be satisfied with the combustion request of detached brick; using the ameliorated combustor with the virtue of coaxial, swirling and crossed, the average temperature is up to 1088℃, and sometimes can arrive at 1250℃ or even more, the flame color and clarity degree show superiority compared with the combustion using diesel oil, and the combustor with gas burns more adequately than with diesel oil. By this token, the premixing ability of coaxial swirling crossed combustor is much better, the clean combustion of low-press hot gas comes true, and yielding request of detached brick can be satisfied. Numerical analysis results indicate, the out press of combustor decreases with increasing the value; there is a little backflow about the exit of the core duct of combustor, after gas emission with air possessed enough chemic proportion; when other few combustion components ignored, simulant temperature is up to 1207℃, the error between the temperature of experiment, engineering calculation and numerical simulation can be accepted on the engineering application; the value of mass fraction of CO increases with increasing, mass fraction of O2 initially doesn't exist, but escalates from central section of finite region by the exit of combustor, the mass fraction of combustion outcome CO2, firstly augments and later decreases, the combustion between CO and O2 happens in the space of 0.1～0.8m.The system of hot gas is compared with that of diesel oil through engineering calculation, and thus it can be seen, to meet the need of the combustion atmosphere at 1260℃, every combustor needs consume 36.962Nm3/h of gas and 42.913 Nm3/h of air in an hour. According to the chemic propotion, the coaxial jet combustor and the coaxial swirling crossed combustor, which have been used in the burny experimentation, and the gas furnace MQL-2000, blower, valve, and other corresponding equipments are selected for the craft of hot gas.
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