Heating of tunnel kilns in ceramic industry - by lean gas obtd. by partial combustion of solid fuel in gas generator, and by recycling furnace exhaust gases

摘要

A solid fuel is partly burnt in a gas generator with a gas (I) contg. oxygen, so a weak or lean gas (II) at low pressure is obtd. Gas (II) is fed into forced jet injectors together with a compressed propulsion gas (III) obtd. from the kiln, thus producing a gas mixt. (II-III) at high pressure. The gas mixt. is then fed into burners in the kiln so the gases travel at high velocity out of the burners. The gas mixt. (II-III) is pref. ignited and burnt in the burners, thus achieving a further increase in its exit velocity. The pref. plant includes compressors providing gases I;III) at specified pressures. Wide kilns can easily be heated; and the use of hot exhaust gases from the furnace as gases (I;III) reduces the total fuel consumption.