JPH0414263B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a square direct-fired generator, and particularly to a direct-fired generator (hereinafter referred to as a generator) used in an absorption refrigerator.

(b) Conventional technology As a conventional technology for a square generator used in a lithium-promide aqueous absorption refrigerator, for example, as seen in Publication of Utility Model Publication No. 15729/1972, a square container into which an absorption liquid enters and exits is used. A plurality of parallel rectangular hollow shunts (absorbent liquid passages) are formed at both ends of the tube and communicate with each other, and a heater is inserted into the heating cylinder (furnace cylinder and flue) formed between these shunts. There are burners that send the flame and combustion gas from the bottom to the top.

(c) Problems to be Solved by the Invention The above-mentioned conventional square generator has the advantage that it is easy to weld the joints of the container and the absorption liquid passage, which is desirable as a generator for an absorption refrigerator that requires a high degree of airtightness. Also, since it is square, it has the advantage of being able to utilize a smaller space more effectively when incorporated into an absorption chiller than a round type, but the outer wall of the rectangular absorption liquid passage directly receives high-temperature flames. Since it has many places that are locally heated, it has the disadvantage that these places are easily corroded by the lithium bromide aqueous solution. In addition, excessive air bubbles generated due to local heating of the container or absorption liquid passage tend to impede the flow of liquid at the bottom of these areas, causing local concentration and crystallization of the absorption liquid. was.

In addition, in order to prevent local concentration due to stagnation of liquid and bubbles, a generator has been proposed in which a heat insulating material is placed at the bottom of the container where the absorption liquid enters and exits, but this generator does not utilize the heat of flame or combustion gas. The problem is that the degree of

In view of these problems, the present invention can alleviate stagnation of liquid and bubbles, reduce local heating of absorption liquid passages and local concentration of absorption liquid, reduce corrosion of structural members, and reduce flame and combustion gas. The object of the present invention is to provide a square-shaped direct-fired generator for an absorption refrigerator that can also increase the degree of heat utilization.

(d) Means for Solving the Problems The present invention provides a rectangular direct firing generator for an absorption refrigerating machine as a means for solving the above problems by connecting the flue to the rear of the furnace. The solution passages are arranged vertically at the boundary between the furnace and the flues on both sides in communication with the solution distribution part, and the passages are arranged symmetrically on both sides of the furnace, and the solution passages are arranged vertically at the boundary between the furnace and the flues on both sides. A group of solution tubes are arranged vertically, and a combustion gas outlet with the same opening area located at the most downstream part of each flue is formed in the solution flow part so as to pass through it. A plurality of solution inlets are formed at the bottom of the flow section, and a solution outlet and a vapor outlet are formed above the solution flow section.

(E) Effect According to the means of the present invention, the flues are formed symmetrically around the furnace, and the gas discharge ports of each flue are formed with the same opening area, so that the combustion gas is This provides an almost uniform flow inside the generator without any drifting, and since the vertical solution passage is placed at the boundary between the furnace and the flue, the temperature of the combustion gas flowing into the flue is lowered and the temperature of the flue is lowered. This has the effect of preventing overheating of the solution tube group on the upstream side, and a large number of solution inlets are formed at the bottom of the solution flow section, and a solution outlet and a vapor outlet are formed above the solution flow section. Therefore, it has the effect of alleviating the stagnation of bubbles and solution at the bottom of the solution flow section and within the vertically disposed solution pipes and solution passages. Due to these effects, both the flame and combustion gas on the heating side and the solution on the heated side flow smoothly in the generator, and the degree of heat exchange between them increases, resulting in local heating of the generator and Local concentration of the absorption liquid is reduced and corrosion of the generator components is reduced.

(F) Embodiment FIG. 1 is a partially cutaway side view showing the schematic structure of an embodiment of a square direct-fired generator for an absorption refrigerator according to the present invention, and FIG. It is a cross-sectional view of the -X section seen from the front side of the generator. Moreover, FIG. 3 is a cross-sectional view of the Y-Y cross section of FIG. 1 viewed from above the generator.

In the direct-fired generator for absorption refrigerating machines (hereinafter referred to as the generator) shown in these figures, 1 is a square outer cylinder, and 2 is a square inner cylinder, which is connected to the inner cylinder wall. Solution flow portions 3, 4, 5, 6, 7, and 8 are formed between the outer cylinder 1 and the wall of the outer cylinder 1, through which bubbles of an absorbing liquid (for example, lithium bromide aqueous solution) and refrigerant vapor (for example, water vapor) flow. 9 is a furnace formed in the center of the generator, and flues 10 and 11 communicating with the rear of this furnace are formed symmetrically on both sides of the furnace 9,
Further, solution passages 12 and 13 are vertically disposed at the boundaries between the furnace 9 and the flues 10 and 11 on both sides thereof, which communicate with the solution flow sections 3, 4 and 8, respectively. That is, the furnace 9 and the flues 10 and 11 are surrounded by a solution passage through which the absorbing liquid flows and a solution distribution part. 1
4 and 15 are combustion gas exhaust ports located at the most downstream parts of the flues 10 and 11, respectively; these exhaust ports 14,
15 are formed at right angles to the respective flues 10 and 11, are formed to penetrate through the solution flow parts 6 and 7 on both sides of the direct combustion generator, and are formed to have the same opening area. Note that 16 is, for example, a flame inlet of a gun-type burner.

In addition, P, P... groups are solution tube groups communicating with the solution distribution parts 3 and 8, and these solution tube groups are respectively connected to the flue 1.
0 and 11 are arranged vertically from the upstream side to the downstream side. P _E is an introduction pipe for an absorption liquid sent by a pump from an absorber (not shown) of the absorption refrigerator, and this introduction pipe is connected to an absorption liquid introduction chamber 17 provided at the bottom of the generator. The bottom wall of the outer cylinder 1, which serves as a partition wall between the absorption liquid introduction chamber 17 and the solution distribution section 8, is provided with a number of holes of the same size at predetermined intervals. That is, the solution flow section 8 is formed with a large number of solution inlets E, E, . In addition, P ₀ is a liquid lifting pipe through which the bubbles of the absorption liquid heated and concentrated in the generator and the refrigerant vapor generated flow, and by connecting this liquid lifting pipe to the outer cylinder 1, the upper side of the solution distribution part is That is, the solution flow section 3 has an outlet O for the solution and vapor.

Although not shown, the solution outlet and the vapor outlet may be formed separately. For example, by widening the distance between the upper wall of the outer cylinder 1 and the upper wall of the inner cylinder 2, a liquid layer and a vapor layer are formed in the solution flow section 3, and a vapor outlet communicating with the vapor layer and a solution communicating with the liquid layer are formed. An outlet may also be provided in the solution flow section 3.

Furthermore, 18, 18... are the outer cylinder 1 wall, the inner cylinder 2
This is a combustion gas passage surrounded by walls, solution passages 12 and 13 walls, or solution tube P walls.

In the generator configured in this way (hereinafter referred to as the main generator), the heat (radiant heat) of the high temperature (approximately 1100°C) flame and combustion gas in the furnace 9 is transferred to the solution distribution parts 3 and 8 and the solution passage 12. , 13, the temperature of the combustion gas flowing out from the rear of the furnace 9 to the flues 10, 11 on both sides decreases (to about 900° C.). In this way, since the combustion gas whose temperature has been lowered flows into the flues 10 and 11, overheating of the absorption liquid in the solution tubes P disposed on the upstream side of these flues is prevented, and the refrigerant in these tubes is prevented from overheating. Excessive generation of steam is also prevented. And these solution tubes P, P
...bubbles of refrigerant vapor are generated within the solution tube, and as the bubbles rise, the concentrated absorption liquid is pumped from the bottom to the top and flows smoothly inside the solution tube.

On the other hand, although high-temperature heat is applied to the absorbent liquid in the solution passages 12 and 13, the amount of the liquid is much larger than that in the solution tube, so overheating of the absorbent liquid in the solution passages is also prevented. Therefore, the solution passage 12,1
The absorption liquid in the tube 3 flows smoothly as well as in the solution tube.

In addition, the flow of the absorbent liquid and bubbles in the solution flow sections 4, 5, 6, and 7 is maintained well, almost the same as in the solution tube group.

On the other hand, the flow of the absorption liquid in the solution distribution section 8 is controlled by the solution distribution sections 4, 5, 6, and 7 formed vertically.
There are also a large number of solution inlets E, E..., which are not facilitated by the buoyancy of air bubbles as in the solution passages 12, 13 and the vertically arranged solution tubes P, P...
It is maintained well because it is promoted by the inertial force of the absorbent flowing in from the inlet.

Then, the absorption liquid and air bubbles that have risen to the solution distribution section 3 flow out from the outlet O and rise through the liquid pumping pipe _P0 , as in the conventional generator, and then flow through the absorption refrigerating machine's gas-liquid separator (not shown), for example. ). Further, a part of the absorption liquid that has risen to the solution distribution section 3 descends through the solution distribution sections 6 and 7, and an absorption liquid circulation circuit is formed on both the left and right sides of the furnace 9.

In this way, in this generator, the absorption liquid circulates and flows smoothly, preventing stagnation of the absorption liquid and resulting excessive local temperature and concentration increases. corrosion is reduced.

Furthermore, in this generator, combustion gas flows through flues 10 and 11 that are symmetrical with the furnace 9 at the center, and exhaust ports with the same opening area are formed perpendicularly to the most downstream parts of the flues 10 and 11. Since the combustion gases flow out uniformly from each of the combustion gases 14 and 15, the imbalance in the flow of combustion gas is reduced. Furthermore, in the flues 10 and 11, where the combustion gas temperature is lower than that in the furnace 9, there are many solution pipes P, P...
Since the heat exchange area is increased by providing the group, the imbalance in the amount of heat exchanged between the high and low combustion gas temperature regions is also reduced.

As mentioned above, the smooth flow of the absorption liquid and the reduction of unevenness in the amount of heat exchanged and the unevenness in the flow of combustion gas combine to raise the temperature of the absorption liquid almost uniformly in this generator, resulting in local heating of the absorption liquid. In addition, highly efficient heat exchange and generation of refrigerant vapor (absorbent concentration) are achieved.

(G) Effects of the Invention As described above, the generator of the present invention takes advantage of the advantages of the conventional square direct-fired generator, while also achieving the effect of maintaining a good and smooth flow of the absorbent and reducing the imbalance in the flow of combustion gas. It also has the effect of preventing local heating, local concentration of absorption liquid, and corrosion of generator components, which were disadvantages of square direct-fired generators, and highly efficient heat exchange and absorption. It is of high practical value as it can achieve concentration of liquid.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway side view showing a schematic structure of an embodiment of a square direct-fired generator according to the present invention, and Fig. 2 is a cross section taken along line XX in Fig. 1, viewed from the front side of the generator. The sectional view, FIG. 3, is a sectional view of the YY section in FIG. 1, viewed from above the generator. 1...Outer cylinder, 2...Inner cylinder, 3, 4, 5, 6, 7, 8
...Solution distribution part, 9...Furnace, 10, 11...Flue, 1
2, 13... Solution passage, 14, 15... Combustion gas outlet, E... Solution inlet, O... Outlet, P... Solution pipe.

Claims (1)

[Claims] 1. In a rectangular direct-fired generator consisting of a furnace, a flue, a solution distribution section provided around the flue and the furnace, and a group of solution tubes that communicate with this solution distribution section, it communicates with the rear of the furnace and A flue formed symmetrically on both sides, a group of solution tubes installed perpendicularly to each flue, and the same opening formed perpendicular to the flue at the lowest downstream part of each flue and penetrating the solution flow section. A combustion gas outlet with a large area, a solution passage that is provided perpendicularly to the boundary between both sides of the furnace and the flue and communicates with the solution distribution section, a plurality of solution inlets formed at the bottom of the solution distribution section, and a solution distribution section. and a solution and steam outlet formed on the upper side of the direct-fired generator.