JPS6210354B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a direct-fired high-temperature regenerator, and more particularly to a direct-fired high-temperature regenerator (hereinafter sometimes simply referred to as a regenerator) used in an absorption refrigerator cycle.

The regenerator is a device that heats and concentrates a dilute lithium bromide (hereinafter referred to as LiBr) solution that has absorbed refrigerant vapor generated in the evaporator in an absorption refrigerator cycle to obtain a concentrated LiBr solution and refrigerant vapor. In the regenerator of an absorption refrigerator cycle that uses LiBr solution as the absorption liquid, the liquid temperature is 160°C or higher, and the LiBr concentration of the liquid is 60°C or higher.
It is concentrated to 65%, but as shown in Figure 1, LiBr
It has been confirmed that when the LiBr concentration of the solution is at the above concentration level (examples with LiBr concentrations of 62% and 65% are shown in the figure), the corrosion rate of metal increases rapidly when the concentration exceeds 175°C. ing.

Therefore, when designing and manufacturing a regenerator, it is necessary to improve the heat exchange performance, uniform the amount of heat exchange inside the regenerator, and maintain the liquid temperature uniformly at a low temperature (below 175℃). In order to prevent local concentration due to the occurrence of stagnant areas of the liquid, it is necessary to flow the liquid uniformly.

A conventional regenerator consisting of a furnace cylinder section and a solution tube group section will be explained with reference to FIGS. 2, 3, and 4. The regenerator 1 includes a burner 10, a furnace tube 11, a solution tube 12 following the furnace tube 11, an outer tube 13, and a chimney 14. Furnace tube 11 determined by the dimensions of flame 21
As shown in Fig. 3, the upper part is flat and the lower part is round. This is because boiling occurs from all around the furnace cylinder, but due to the bubbles 31 generated at the bottom.
This is to uniformize the liquid temperature by smoothly moving the LiBr solution 30 to the top, and to prevent local concentration. On the other hand, multiple solution tubes 1
As shown in FIG. 4, the solution tube group section constituted by 2 has a flat top and bottom, so that boiling mainly occurs within the solution tube 12, so there are relatively few problems in liquid flow.

Although a regenerator with such a structure is desirable from the viewpoint of preventing corrosion caused by LiBr,
1 and the outer cylinder 13 are round, there is a limit in terms of manufacturing cost reduction and VA, and there is also a drawback that the occupied area becomes large when it is incorporated into a refrigerator cycle. Furthermore, since it is difficult to reduce the amount of LiBr solution 30 present in the vessel, there is a drawback that the start-up time at startup and the operation time for diluting the LiBr solution at shutdown are relatively long.

In order to overcome the above-mentioned drawbacks of the conventional round regenerator, attempts have been made to develop a rectangular regenerator. FIG. 5 shows the furnace cylinder of a conventional vertical rectangular regenerator in which the rectangular regenerator is arranged vertically.
Trouble occurs due to poor liquid flow in the furnace cylinder portion of the vertical rectangular regenerator. That is, the LiBr solution 30 flows smoothly due to the generated bubbles 31 on the top and side surfaces of the furnace cylinder 11 in FIG. 5, but at the bottom, due to the floating effect of the bubbles 31,
The horizontal movement of the LiBr solution 30 and the bubbles 31 is obstructed, forming a stagnation area 40 of the liquid and bubbles,
Concentration of the LiBr solution and temperature rise occur, causing local corrosion.

An object of the present invention is to eliminate the above-described drawbacks of the prior art and to provide a rectangular regenerator that is free from corrosion problems due to poor liquid flow despite its rectangular shape.

The gist of the present invention is to provide a direct-fired high-temperature regenerator comprising a furnace cylinder part and a solution tube group part, in which the inner cylinder and outer cylinder of the furnace cylinder part and the solution tube group part are formed in a rectangular shape and inclined. A direct-fired high-temperature regenerator is characterized in that a rectifying plate is provided in a gas-liquid boundary area at the center of an outer cylinder.

The circumstances that led to the completion of the present invention will be explained below.

In the vertical rectangular regenerator shown in Figure 5, there is a stagnation area 40 at the bottom.
is formed and local corrosion occurs there, but the sixth
As shown in the figure, the outer cylinder 13 and the furnace cylinder 11 are set vertically by θ.
When the liquid is tilted to an angle of 1°, the bottom stagnation region disappears and a good liquid flow condition is achieved. Preferably, the inclination angle θ is 10 to 30°.

However, when the influence of the inclination of the container in the solution tube group is considered, a problem arises as a liquid flow pattern as shown in FIG. 7 is obtained. That is, the flow of the liquid forms an asymmetrical circulation on the left and right sides, with the circulation on the left side being particularly strong and small, but when such a phenomenon occurs, local corrosion is likely to occur due to concentration of the liquid, etc.

Therefore, the present inventors investigated ways to improve asymmetric circulation by tilting the vessel, and as a result, as shown in Figure 8,
It has been found that by providing the flat rectifying plate 50, the left-right asymmetric circulation can be improved. Furthermore, as a result of studying the influence of the rectifier plate 50 on the liquid flow in the furnace cylinder, the inventors found that the liquid flow is dominated by the flow in the side of the furnace cylinder, and the water level above the side is lowered, as shown in FIG. is higher, but the flow near the rectifying plate 50 at the upper center is small and it has been confirmed that there is no effect.

As the current plate 50, in addition to the above-mentioned flat plate type, the V-type current plate shown in FIG. 10a and the inverse Λ (lambda) type current plate shown in FIG. This is not preferable because it also promotes liquid circulation, and although the latter improves liquid flow in the same way as flat rectifying plates, it is inferior to flat rectifying plates in terms of manufacturing cost.

FIGS. 11, 12, and 13 show embodiments of the rectangular regenerator of the present invention, and according to these figures,
The rectangular regenerator is tilted at θ°, and the furnace cylinder 11 inside the regenerator is tilted at θ°.
A flat rectifying plate 50 is installed above the solution tube 12. In addition, Figure 12 shows XII-XII in Figure 11.
A cross-sectional view along the line, Figure 13 is the same as in Figure 11.
It is a sectional view along a line.

Although the present invention has been explained using a regenerator as an example, the field of application of the present invention is not limited to this, and the present invention can be applied to all tubular heat exchangers for concentrating corrosive liquids. Of course.

As described above, according to the present invention, the occurrence of local corrosion due to poor liquid circulation, which is a drawback of square regenerators, is eliminated by sloping the regenerator and installing a rectifier plate inside the regenerator, so local corrosion is significantly reduced. It has the advantage of being Furthermore, since it is square, it has advantages such as reduced manufacturing cost and occupied area.

[Brief explanation of the drawing]

Fig. 1 is a graph showing the relationship between the concentration and temperature of LiBr solution and the corrosion rate of metal, Fig. 2 is a vertical cross-sectional view of a conventional round regenerator, and Fig. 3 is a graph showing the relationship between the concentration and temperature of LiBr solution and the corrosion rate of metal.
Figure 4 is a cross-sectional view taken along the - line in Figure 2, Figure 5 is a cross-sectional view of the furnace cylinder of a conventional rectangular regenerator, and Figure 6 is a furnace of an inclined rectangular regenerator. 7 is a cross-sectional view of the solution tube group of the tilted rectangular regenerator; FIG. 8 is a cross-sectional view of the solution tube group of the tilted rectifier of the present invention having a rectifying plate; FIG. FIG. 9 is a sectional view of the furnace tube part of the inclined angle regenerator of the present invention having a rectifying plate, FIG. 10 is a sectional view of the solution tube group part of an inclined angle regenerator having another rectifying plate, The figure is a longitudinal cross-sectional view of the regenerator of the present invention, FIG. 12 is a cross-sectional view taken along line XII--XII of FIG. 11, and FIG. 13 is a cross-sectional view of the regenerator of FIG.
It is a sectional view along a line. 1... Regenerator, 10... Burner, 11... Furnace tube, 12
...Solution pipe, 13...Outer tube, 14...Chimney, 40...Stagnation area, 50...Buffer plate.

Claims (1)

[Scope of Claims] 1. In a direct-fired high-temperature regenerator comprising a furnace cylinder part and a solution tube group part, the inner cylinder and the outer cylinder of the furnace cylinder part and the solution tube group part are square and inclined, A direct-fired high-temperature regenerator characterized in that a rectifying plate is provided in the gas-liquid boundary area at the center of the outer cylinder. 2. The direct-fired high-temperature regenerator according to claim 1, wherein a flat rectifying plate is used as the rectifying plate, and the flat rectifying plate forms an acute angle with the outer cylinder so as to dam the flow of liquid. 3. The direct-fired high-temperature regenerator according to claim 1 or 2, wherein the degree of inclination of the inner cylinder and the outer cylinder is 10 to 30 degrees from the vertical.