SU1691677A1 - Shaft furnace for calcination of lump material - Google Patents

Abstract

The invention relates to devices for the firing of bulk materials and can be used in metallurgy, construction, chemistry and other industries. The aim of the invention is to increase thermal efficiency by uniformly distributing the heat load over the cross section and height of the furnace. The goal is achieved by installing in the furnace shaft vertical rods of heat-resistant material installed at a distance (0.14-0.37) d from each other, where d is the diameter of the cross-section of the mine. The application of this invention allows to reduce fuel consumption for the process 3 Il.

Description

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The invention relates to devices for the firing of bulk materials and can be used in metallurgy, construction, chemistry and other industries.

The purpose of the invention is to increase thermal efficiency by uniformly distributing the heat load over the cross section and height of the furnace.

Figure 1 shows the longitudinal and transverse sections of the furnace; figure 2 - the location of the rods at the height of the low-tonnage mine (up to 100 tons / day) furnace; on fig.Z - the location of the rods at the height of the shaft large-tonnage (over 100 tons / day) furnace; Fig. 4 shows the dependence of the resistance of layer materials on the flow rate to blow with a distance between the rods from 0.14 to 0.37d.

The shaft furnace 1 for firing bulk material consists of heating zones 2, firing 3 and cooling 4. Combustion system 5 can be made in the form of beam burners, central in combination with peripheral external combustion chamber. The vertical heat-resistant rods 6 are installed in the mine at a distance of 0.14-0.37d from each other, where d is the diameter of the mine cross-section. The rods are fastened to the top of the shaft.

The arrangements of the rods may vary depending on the furnace abarites (Fig. 2). If the furnace has a small capacity (up to 100 tons / day), then the rods extend the entire height of the shaft (Fig. 2). In the cooling zone, the pillars may end in the middle of its height, since in the lower part the uneven geomagnetic

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wear, but HMORI places half a meter with cooling air supply through the supply system 7. In the lower part of the burning zone of large-capacity furnaces, where the temperature conditions are particularly stressful, uniform distribution is provided by the fuel supply and combustion system, the presence of rods is optional. Therefore, the rods are installed both on the top of the furnace (and extend to the middle of the burning zone) and in the cooling zone (Fig. 3).

The furnace works as follows. The calcined material (limestone) is served on top in the heating zone 2. The material, heated in countercurrent with furnace gases, from the heating zone enters the burning zone 3, where it dissociates. From the burning zone 3, the calcined material enters the cooling zone 4, where it is cooled to 80-100 ° C and unloaded from the furnace. The lime cooling air is evenly introduced into the cooling zone. Uniform air distribution over the zone height is carried out with the help of vertical rods, along which there are zones of low hydraulic resistance, and since the number of these rods is large, the resistance of the layer in the space between the rods and they are comparable along the rods, which ensures uniform air distribution over the layer at the entire height of the zone.

Fuel or semi-gas is introduced into the burning zone and distributed over the entire cross-section of the burning zone. The fuel is burned or afterburned in the burning zone 3 in the atmosphere of heated air coming from the cooling zone 4. Physical heat

precombustion in the burning zone consumes limestone dissociation

Uniform distribution of combustion products thanks to those installed in the mine

vertical rods contributes to the completion of heat exchange along the height of the burning zone, and gases with a temperature of 900-950 ° C enter the heating zone 2, where the physical heat of the combustion products is consumed

for limestone heating. The furnace gases leaving the preheating zone have a temperature of 280-300 ° C. The heat exchange at the height of the preheating zone 2 is completed completely.

The arrangement of rods should

as dense as possible so that the number of zones with reduced hydraulic resistance is maximum. However, the rods should not prevent the material being processed at once, i.e.

they get stuck.

The application of the invention allows to reduce fuel consumption per process.

Claims (1)

Claims of an Invention Shakhna kiln for lump material containing height-divided technological zones, fuel supply and combustion system, characterized in that, in order to increase thermal efficiency due to uniform distribution of heat load over the cross section and height of the kiln, it is fitted with fixed vertically in its upper part by heat-resistant rods installed at a distance of (0.14-0.37) d relative to each other, where d is the equivalent diameter of the mine’s cross-section. , n. J x - 9 N -Lh4 1LU1691 Fig 2. (YigZ SP BUT 4jfSt; Of 6.55 0.5 Ofti ABOUT, OfО, 6Oi FIG 4 Cos rods S # 4w / c