JPH0440Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a waste heat recovery device for coke dry fire extinguishing equipment that enables natural circulation of fluid in an evaporator system.

(Prior Art) In the conventional waste heat recovery device of coke dry fire extinguishing equipment, the heat transfer tubes of the evaporator were arranged horizontally.

Therefore, a high-temperature, high-pressure circulation pump was required to forcefully circulate the fluid to prevent vapor lock, but if such a circulation pump were installed, the equipment would be complicated and expensive, and a large amount of power would be required. There were other problems.

Furthermore, as shown in FIG. 5, a natural circulation boiler is known in which the heat exchanger tubes of the evaporator 6 are serrated and inclined upward with respect to the flow direction. Therefore, there were problems such as the height of the entire boiler becoming high and extremely expensive.

Further, Japanese Utility Model Application No. 58-48746 discloses an evaporator 6 having an inclined heat exchanger tube 9 having headers 10 and 11 at its inlet and outlet, respectively, as shown in FIG. The flow rate of canned water in the heat transfer tube of the evaporator 6 must be maintained above a certain level for heat removal. For this reason, a large amount of circulating water is required, and the downcomer pipe 1
2. The riser pipe 13 becomes larger. In addition, since a space is required for welding the heat exchanger tubes 9 and headers 10 and 11 at the header part, and because the size of the header is larger than the heat exchanger tubes, the distance between the heat exchanger tubes in the vertical direction becomes wider.
There were problems such as the inability to lower the height of the boiler, which made the boiler expensive.

(Problems to be solved by the invention) As explained above, the conventional forced circulation system for boilers requires a high temperature, high pressure circulation pump, resulting in high equipment costs and high operating costs.

In addition, the natural circulation method had the problem of higher equipment costs because the height of the entire boiler was higher.

The present invention aims to provide a waste heat recovery device for coke dry extinguishing equipment that eliminates the circulation pump, simplifies the equipment, does not increase the height of the boiler, reduces equipment cost, and reduces power consumption. This is the purpose.

(Means and effects for solving the problem) The present invention is characterized in that only the top part of the evaporator heat transfer tube having a gas inlet at the top is inclined upward by 2 degrees or more, and the other heat transfer tubes are provided horizontally. In this waste heat recovery device for coke dry extinguishing equipment, high-temperature gas flows from the top of the evaporator, first heating the inclined heat transfer tubes and generating steam.

The generated steam moves upward along the slope,
Since the fluid flows through the header pipe and into the riser pipe, a difference in specific gravity is created between the saturated water in the downcomer pipe and the air-water mixture in the riser pipe, so that the fluid is self-starting and circulates naturally.

(Example) Hereinafter, an example of the present invention will be described based on the drawings.

FIG. 1 shows an embodiment of the present invention, and FIG. 2 shows details of the evaporator section.

In the figure, 1 is a cooling chamber that cools the red-hot coke, 2 is a flue through which high-temperature gas is sent out after cooling the red-hot coke in the cooling chamber, and 3 is a waste heat recovery device.

The waste heat recovery device 3 is composed of a steam drum 4, a superheater 5, an evaporator 6, an economizer 7, a descending pipe 12, a rising pipe 13, etc. The evaporator 6 is provided with an inlet and an outlet header 10, 11. It is being The heat exchanger tubes of this evaporator 6 are composed of a horizontal heat exchanger tube 8 and an inclined heat exchanger tube 9 disposed at the end and having an upward slope, that is, an inclination angle 15 with respect to the gas-liquid mixed fluid.

Figure 3 shows that the inclined heat exchanger tube 9 is heated to steam 1 by high-temperature gas.
4 is shown.

When the waste heat recovery device 3 is in operation, the high-temperature gas generated by cooling the red-hot coke in the cooling chamber 1 is sent to the waste heat recovery device 3 for waste heat recovery. via evaporator 6
The steam flows from the upper part of the tube, heats the inclined heat exchanger tube 9, and generates steam 14. The generated steam 14 moves upward along the slope and reaches the outlet header 11 and riser pipe 13.
Since the steam 14 flows into the horizontal heat exchanger tube 8, the steam 14 acts as a natural circulation force, can be self-starting, and even without a circulation pump, natural circulation in the horizontal heat exchanger tube 8 is performed without vapor lock.

The inclination angle 15 of the inclined heat exchanger tube 9 is an economically permissible angle of 2 to 10 degrees. The minimum angle of 2° is the angle that must be secured to allow the steam 14 to slide up the slope of the inclined heat exchanger tube 9, and the maximum angle of 10° is to be maintained in the maintenance space between the superheater 5 and the evaporator 6. The maximum angle limit can be even larger for boilers with a large maintenance space.

In particular, the height from the evaporator outlet to the air/water drum 4 is 1/2 of the height from the evaporator inlet to the air/water drum 4.
If the above conditions are met, sufficient natural circulation force can be ensured,
Experiments have shown that it is even more effective.

The waste heat recovery device 3 of the coke dry fire extinguishing equipment is of a type in which gas flows in from the top, and an appropriate height between the evaporator 6 outlet and the air-water drum 4 can be ensured, and the above conditions are satisfied. Circulating boilers are best.

In addition, the inlet header 10 and the horizontal heat exchanger tube 8, and the outlet header 11 and the inclined heat exchanger tube 9 are connected by connecting two heat exchanger tubes 8, 9 to each header tube 10, 11, as shown in FIG. By piping the two heat exchanger tubes 8 and 9 in parallel, the necessary heat transfer area is secured, the length of each heat exchanger tube is shortened, and the resistance inside the heat exchanger tubes 8 and 9 is reduced. , which is even better because it facilitates natural circulation.

It should be noted that the present invention is not limited to the above-described embodiments, and it goes without saying that various changes can be made without departing from the gist of the present invention.

(Effect of the invention) In the waste heat recovery device of the coke dry extinguishing equipment of the present invention, the heat transfer tubes are arranged horizontally in the evaporator, and only the last heat transfer tube is inclined upward with respect to the flow direction, so that the fluid is self-starting and circulates naturally. This eliminates the need for a circulation pump, and since it is basically a horizontal heat transfer tube group, there is no need to increase the height.

Therefore, it is possible to save energy by simplifying equipment and reducing power consumption. In addition, various excellent effects can be expected, such as lower equipment costs and operation and maintenance costs.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of one embodiment of the present invention, Fig. 2 is a detailed explanatory diagram of the evaporator section, Fig. 3 is a diagram showing the movement of the inclined tube and bubbles, and Fig. 4 is the evaporator section of the present invention. Figure 5 shows another embodiment of the evaporator (heat exchanger tubes are serrated and sloped over the entire length) of a conventional natural circulation boiler. FIG. 6 is a diagram showing an evaporator of a conventional natural circulation boiler (each inclined heat exchanger tube is connected to an inlet and an outlet header). 1... Cooling chamber, 2... Flue, 3
...waste heat recovery device (boiler), 4 ... air-water drum, 5 ... superheater, 6 ... evaporator, 7 ... economizer, 8 ... horizontal heat transfer tube, 9 ... inclined heat transfer tube, 10
...Entrance header, 11...Outlet header, 12
... Descending pipe, 13 ... Rising pipe, 14 ... Steam (bubbles), 15 ... Inclination angle.

Claims (1)

[Scope of utility model registration request] A waste heat recovery device for coke dry extinguishing equipment, characterized in that only the top of an evaporator heat transfer tube having a gas inlet at the top is inclined upward by 2 degrees or more, and the other heat transfer tubes are installed horizontally.