JPS6017911B2 - concrete chimney - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a concrete chimney whose chimney body is air-cooled.

Concrete chimneys with a height of 50 to 6 meters are widely used because they are cheaper than steel chimneys and require no maintenance.

When used in incineration plants, etc., the flue gas temperature is 1
Since the temperature is as high as 00 to 150 degrees Celsius, in order to prevent the concrete of the chimney body from heating up, straining and cracking, as shown in Fig. A refractory material 2 such as brick or castable is placed in the main body 1.
The concrete is supported and lined with a support bracket 6 embedded in the chimney as shown in FIG. 3, and outside air is taken into the gap 3 between the lining refractory 2 and the chimney body 1 to air-cool the concrete. This outside air is taken in through a plurality of ventilation holes 4, 4, etc. drilled on the circumference at the bottom and middle height positions of the chimney body 1, and exhausted outward through the ventilation hole 4' at the top of the chimney. There is. However, in the chimney as described above, it is necessary to increase the flow velocity of the flue gas in order to improve the diffusion of the flue gas from the viewpoint of pollution prevention, and for this reason, the top of the chimney is supported by a support metal fitting 7a as shown in Fig. 4. Since the inner refractory 7 is used to restrict the pressure and increase the internal pressure, if a crack occurs in the lining refractory 2, smoke will enter the gap 3 through the crack in the refractory 2, causing the smoke to leak through the ventilation hole at the mid-height of the chimney. 4, a phenomenon in which smoke is discharged outside has occurred, and as a result, there have been many cases of damage to residents and trees near chimneys. This invention was made to solve the above-mentioned problems, and its purpose is to improve the cooling effect and improve fire resistance by sucking chimney cooling air through the smoke ejector action and discharging it from the inside of the chimney top. The purpose is to provide a concrete chimney that prevents smoke damage from coming out of cracks in objects.

An embodiment of the present invention will be described below with reference to FIG. Since the chimney body 1 is lined with a refractory 2 and cooling air is passed through the gap 3 in the same manner as in the subordinate structure, the same parts are given the same reference numerals and detailed explanations are omitted. Reference numeral 8 in the figure is a refractory constriction part provided at the top of the chimney body 1. Reference numeral 9 denotes a discharge port for the chimney cooling air introduced into the gap 3, which is connected to the inside of the top of the chimney body 1.

Reference numeral 10 is a constricted portion provided at the top of the lining refractory 2.

The cooling air introduced into the gap 3 is sucked in by the ejector action of the exhaust smoke and is discharged from the exhaust port 9 to the inside of the chimney top.

When the throttle parts 8 and 10 made of refractory material are provided at the top of the chimney as in this embodiment, the ejector effect due to smoke exhaust is further increased, and cooling air can be sucked and discharged with a large suction force. According to this invention, since the suction power of the cooling air is large, the air intake vent 4 (the first
(see figure) is provided only at the bottom of the chimney, for example, below the bonito path 5. The concrete chimney of the present invention is as described above, and the chimney cooling air is sucked in by the ejector action of the flue gas and discharged from the inside of the chimney top, so the chimney cooling effect can be improved, and the lining Even if cracks occur in the refractory and exhaust smoke inside the chimney flows into the air cooling gap, the exhaust smoke will no longer be discharged outside from the middle of the chimney body.
It is possible to reliably prevent the smoke damage that occurs in the past.

[Brief explanation of the drawing]

Figure 1 is a vertical cross-sectional view of a conventional concrete chimney, Figures 2 and 3 are enlarged cross-sectional views of sections A and B in Figure 1, and Figure 4 is the main part of a conventional chimney with the top narrowed. FIG. 5 is an enlarged half-sectional view of the main part of the concrete chimney of the present invention. 1... Chimney body, 2... Refractory, 3... Gap, 4
...Air vent, 9...Exhaust port. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] 1. In a concrete chimney body lined with refractory material keeping an appropriate gap, outside air is drawn into the gap between the lining refractory material and the chimney body for air cooling, and the lower part of the chimney body is A ventilation hole for outside air intake is provided, and an outlet for the chimney cooling air introduced into the gap is opened inside the top of the chimney body, and a constriction part is provided at the top of the refractory lining, and the chimney is cooled by the ejector action of the exhaust smoke. A concrete chimney that is characterized by being designed to suck in air and exhaust it.