JPS5836277B2 - Heat storage and regeneration heat exchanger - Google Patents

Description

[Detailed Description of the Invention] The present invention provides a method for constantly circulating hot gas and heat-receiving gas.
The present invention relates to a heat storage and regeneration type heat exchanger that transfers heat between both gases.

A typical regenerative heat exchanger conventionally used for heat exchange between large amounts of gas is a rotary regenerative heat exchanger.

This heat exchanger rotates a round-shaped heat storage chamber containing a heat storage medium, and allows hot gas and heat-receiving gas to flow in the direction of the rotation axis in a heat storage manner, thereby exchanging heat between the two gases. However, in order to reduce the leakage phenomenon between the two gases, the rotating body must be specially designed to take into account thermal expansion.

Of course, such devices have been attempted in the past, as seen in Japanese Patent Publication No. 4393/1983, but they have not fundamentally solved the various problems caused by thermal expansion.

In recent years, from the standpoint of energy conservation, heat recovery from combustion gas discharged from various plants has become essential.Especially in flue gas desulfurization and flue gas denitrification, efficient methods with less gas leakage have become essential. Heat recovery is essential.

The present invention proposes a regenerative heat exchanger that can be incorporated into flue gas desulfurization equipment or flue gas denitrification equipment, in which the heat storage chamber is left stationary without rotating, and the heat exchanger is able to receive heat from hot gas. The present invention provides a heat storage and regeneration type heat exchanger that efficiently exchanges heat between the two gases while continuously circulating the gas through the heat storage chamber.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings. FIG. 1 is a partially cutaway perspective view showing an embodiment of the heat storage and regeneration type heat exchanger according to the present invention, This heat exchanger consists of a total of eight heat storage chambers 2a and 2b that house heat storage media 1 made of a large number of metal plates and are arranged in parallel.
,...2g, 2h.

Each heat storage chamber has two openings, and one of the openings can be communicated with the hot gas introduction section 3 and the heat receiving gas discharge section 4 via a damper. It communicates with the hot gas introduction duct 3 via the damper 5a, and with the heat receiving gas exhaust duct 4 via the damper 6a.

Similarly, the curved opening of each heat storage chamber can be communicated with the hot gas discharge duct 7 and the heat receiving gas introduction duct 8 through dampers. It communicates with the exhaust pipe 7, and communicates with the heat-receiving gas introduction pipe 8 through the pumper 10a.

A damper opening/closing machine 11 for a set of compressed air cylinders is provided in each turner.

Next, to explain the heat exchange mode in the heat exchanger constructed as above, Fig. 1 shows the heat storage chambers 2a, 2b, 2g.
and 2h are in a heat storage state, respectively, and heat storage chambers 2c and 2d
, 2e and 2f are each in a heat dissipation state.

In other words, in each heat storage chamber in a heat storage state, only the pumps leading to the hot gas introduction duct and exhaust duct are kept open, and all the pumps leading to the heat receiving gas introduction duct and exhaust duct are kept closed. Ru.

On the other hand, in each heat storage chamber in the heat dissipation state, all the dampers leading to the hot gas introduction duct and exhaust duct are closed, and only the dampers leading to the heat receiving gas introduction duct and exhaust duct are kept open. be.

The hot gas supplied into the heat exchanger from the hot gas introduction duct 3 passes through the dampers 5a, 5b, 5g and 5h, enters the heat storage chambers 2a+2by2g and 2h, and heats the heat storage medium 1. Thereafter, the hot gas is discharged from the heat exchanger through the exhaust duct 7.

During this time, the heat-receiving gas is supplied into the heat exchanger from the heat-receiving gas introduction port 8, and passes through the heat storage chambers 2cy 2d, 2e, and 2f, receiving heat from the heat storage medium. and 6f, and is discharged to the outside of the heat exchanger from the heat-receiving gas discharge outlet 4.

There is a certain time lag between the heat storage chamber where the heat storage medium is heated by the passage of the hot gas and the heat storage chamber where the heat storage medium is cooled by the passage of the heat receiving gas.
The state sequentially shifts from the heat storage state to the heat radiation state, and from the heat radiation state to the heat storage state.

In other words, hot gas and heat-receiving gas are constantly supplied to the heat exchanger, but the distribution of hot gas and heat-receiving gas to each heat storage chamber is performed in a certain sequence.
The number of heat storage chambers in a heat storage state and the number of heat storage chambers in a heat radiation state are always maintained at the same level, and such a situation requires opening and closing of individual dampers interposed between each heat storage chamber and the hot gas duct and heat receiving gas duct. , is achieved by performing them in a certain sequence.

FIG. 2 is an explanatory diagram showing an example of a sequence regarding opening and closing of dampers, and here, hot gas introduction dampers 5a, 5b, 5g, 5h of the heat exchanger shown in FIG.
And Gumper 6a r6b for discharging heat receiving gas...
・Situations in which the open/close states of 6g and 6h change over time as shown in A to C are shown.

In the heat exchanger of the present invention, each damper through which hot gas is discharged is in the same open/closed state as each damper through which hot gas is introduced, and each damper through which heat receiving gas is introduced is It is in the same open and closed state as each damper through which the discharge is performed.

Now, A-C in Fig. 2 shows the temporal transition of the open and closed states of each damper, and as shown in A, at a certain point, dampers 5a and 5h are fully open, and dampers 5c, 5d, 5e, and 5f are fully open. Fully closed, 5b and 5g are half open and half closed.

On the other hand, 6ay 6b, 6 which is the damper on the heat receiving gas side
g and 6h are fully closed, 6d and 6f are fully open, and 6c and 6f are half open and half closed.

Now, the heat storage chambers 2a, 2b for hot gas and heat receiving gas...
・Assuming that the distribution to 2g and 2h is carried out in the alphabetical order shown in the figure, opening dampers 5b and 6f,
By closing the turnpers 60 and 5g at the same speed, the open/closed state of each turnper can be shifted from A to B in FIG. 2.

Similarly, dampers 50 and 6g are opened, and damper 6
By closing d and 5h at the same speed, the open/closed state of each turnper can be changed from B to C in FIG. 2.

In other words, in the heat exchanger of the present invention, each damper for hot gas and the damper for heat receiving gas in each heat storage chamber are not opened at the same time. The dampers for waste are sequentially opened and closed in the same direction and at the same speed, with a certain time lag in their opening and closing timing, and as a result, in the heat exchanger of the present invention, the heat exchanger is in a heat storage state. The number of heat storage chambers and the heat storage chambers in a heat radiating state are always maintained at the same number.

In this case, each damper can be opened and closed using a known damper opening/closing mechanism, for example, as shown in Figure 1, a damper opening/closing machine with a set of compression cylinders is installed for each damper, as described above. By opening and closing a compressed air valve that is linked to a timer that incorporates a suitable opening and closing timing sequence,
The damper opening/closing machine can be opened and closed.

Although the configuration and heat exchange mode of an embodiment of the present invention have been described above, the heat storage and regeneration type heat exchanger of the present invention is not limited to the specific example shown in the drawings; for example, the number of heat storage chambers is four. , 6 groups, 8 groups, or 10 groups.

However, since the heat exchanger of the present invention is constantly supplied with hot gas and heat-receiving gas and continuously transfers heat between the two gases, it is necessary to include at least four heat storage chambers. The total number of bases is preferably an even number.

As is clear from the above, the heat storage and regeneration type heat exchanger of the present invention having at least four or more heat storage chambers always maintains the same number of heat storage chambers in a heat storage state and heat storage chambers in a heat radiation state. By supplying the hot gas and the heat-receiving gas simultaneously and continuously, it is possible to continuously perform heat exchange between the two gases.

Therefore, the heat exchanger of the present invention is extremely suitable for recovering heat from a large amount of hot gas.

In addition, in the heat exchanger of the present invention, since the heat storage chamber in which expansion and contraction due to heat occurs most often is in a stationary state, consideration must be given to the thermal influence of the rotating body such as in a rotary heat storage and regeneration type heat exchanger. It also has the structural advantage that it is not necessary.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway perspective view showing an embodiment of a heat storage and regeneration type heat exchanger according to the present invention. Fig. 2 is an explanatory diagram showing the opening/closing sequence of the evening chamber in the heat storage and regeneration type heat exchanger shown in Fig. 1. 1... Heat storage medium, 2a''h... Heat storage chamber, 3 ...Hot gas introduction duct, 4...Heat receiving gas discharge duct, 5a~
h...Hot gas introduction damper, 6a"-h...Heat-receiving gas discharge damper, 7...Hot gas discharge turctor, 8...
- Heated gas introduction Gunhar, 9a...Hot gas discharge damper, 10a...Heat receiving gas introduction damper 11...Gumper opening/closing machine.

Claims (1)

[Claims] 1 At least four heat storage chambers containing a heat storage medium are arranged in parallel and integrated, one opening of each heat storage chamber is communicated with the hot gas introduction duct and the heat receiving gas discharge duct via a damper, and A heat storage and regeneration type heat exchanger, which has one opening communicated with a hot gas discharge duct and a heat receiving gas introduction duct via a damper, and is further provided with a damper opening/closing mechanism that opens and closes each of the dampers in a temporally staggered manner.