SU340842A1 - GAS MINING - Google Patents

Description

This invention relates to flame production systems for steam generators of power plants.

In the known gas intake shafts, which serve to supply flue gases to the drying of fuel in a mill, containing a metal thick-walled body with outer and inner insulation and attached to the body supports for the inner insulation in the form of shelves installed with a certain pitch inside the body, a large suction cup air, reaching 30-100% of the amount of flue gases supplied. The main places of the suction in the cold air mine are the gas intake area, the compensator, the joint of the gas intake shaft with the mill inlet and the raw coal feeding chute. The cold air suction adversely affects the performance of the mill and the efficiency of the boiler operation, since this air does not pass through the air preheater and does not participate in cooling the flue gases.

In the proposed gas intake shaft, a thin-walled metal shell with perforated end plates, adjacent to the furnace, mill inlet and flowing of the feed angle, to form an annular cavity filled with hot gas is installed between the casing and the inner insulation in order to eliminate cold air suction devices. by air. Some overpressure is maintained in the annular cavity (10-15 mm in. Art.). In addition, for the passage of hot air through the annular shelves, the latter are perforated, and to compensate for thermal deformations and to ensure the passage of hot air

between the parts of the mine, the housing is equipped with a double wall compensator.

Such an embodiment of the mine allows an increase in efficiency. by 1-2%. FIG. 1 shows a gas intake section.

mines; in fig. 2 - section of the site adjacent the shaft to the furnace; pas figs. 3 - section of the site of the mine adjoining the mill inlet. The gas intake shaft comprises a housing /,

shell 2, inner 3 and outer 4 insulation, annular cavity 5 for supplying hot air, compensator 6, annular shelves 7 and end perforated sheets 5 and 9. The mine works as follows.

Hot air enters the upper part of the annular cavity between the body and the shell and fills it. In the end parts of the mine, adjacent to the furnace and the suction pipe of the mill, as well as in the place of entry

As thin streams through holes 11, 12, and 13 enter the gas intake shaft and, creating an air curtain, interfere with the suction of cold air. The presence of pressure in the annular cavity prevents suction through leaks in the housing itself. For the passage of hot air from one part of the shaft to another, holes 14 are provided in the annular shelves, and the compensator is double-walled.

Subject invention

Claims (3)

1. A gas intake shaft for supplying flue gases to the steam drying the fuel in the mill, and the casing with external and internal thermal insulation and attached to the casing ring shelf supports, characterized in that, in order to eliminate cold air suction, a metal shell is installed between the casing and the inner insulation with perforated end sheets adjacent to the furnace, the mill inlet and the raw coal feed to form an annular ring with the casing cavities filled with hot air. 2. A shaft according to claim 1, characterized in that for the passage of hot air through the annular shelves, the latter are perforated. 3. Mine on PP. 1 and 2, characterized in that, in order to compensate for thermal deformations and to ensure the passage of hot air between parts of the shaft, the housing is equipped with a double wall compensator. FIG)