Patent ID: 8250996

Claim:
A process for burning coal instead of oil comprising the following stages: coal gasification, wherein feeding coal and gasifying agent into a fixed bed gas-generated furnace and gasifying the coal to generate a hot low calorific value gas having a lower heating value in range of 5.02-6.66 MJ/Nm 3 , when anthracite is used, the hot gas has a lower heating value in range of 5.02-5.65 MJ/Nm 3 , and when bitumite is used, the hot gas has a lower heating value in range of 5.65-6.66 MJ/Nm 3 , and a temperature selected above the dew point of the mixture of tar and steam therein, and the gasifying agent is a steam-saturated air, and wherein the coal is a briquette produced from a fine coal, the ash fusibility of the briquette is modified by ash-slag coagulation so that the difference between its deformation temperature DT and softening temperature ST is in range of 150-300° C., and the temperature in the oxidation zone of the fixed bed gas-generated furnace is regulated by varying the saturation temperature of the gasifying agent so that it is lower than the softening temperature ST of the briquette, thus reducing the dust content of the gas; and gas combustion, wherein introducing the generated hot gas into a burner used in steam injection boiler or heating furnace for heavy oil thermal recovery and burning the hot gas therein under a vacuum in range of 50-150 Pa, by mixing with a combustion air, which is introduced into said burner after being preheated to a temperature in range of 160-250° C.