JPS6093273A - Multiple effect absorption type refrigerator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a multi-effect absorption refrigerating machine, and particularly to a multi-effect absorption refrigerating machine suitable for preventing overheating of a burner used in a high-temperature regenerator. It is.

[Background of the invention]

Absorption refrigerators are based on the principle of an absorption cycle in which the circulating refrigerant is separated from the solution by heating under high pressure, evaporated, and then reabsorbed under low pressure. Demand for machines is increasing.

First, the prior art will be explained with reference to FIGS. 1 and 2.

Figure 1 is a block diagram of a conventional multi-effect absorption chiller;
The figure is a sectional view of the high temperature regenerator section.

In Fig. 1, l is an evaporator, which has a built-in cold water pipe 1a for heat exchange with cold water, a refrigerant distribution header 9, and a float valve 14 as shown by the dashed arrow, and evaporates the refrigerant to generate cooling capacity. It is something that makes you

2 is an absorber, which has a built-in rudder 7 for dispersing the cooling water '@2a and concentrated solution, which exchanges heat with the cooling water as shown by the dashed arrow.
The refrigerant evaporated in the evaporator 1 is guided to the absorber 2 as shown by the wave-shaped arrow, and is absorbed into a solution within the absorber 2.

Reference numeral 3 denotes a high-temperature regenerator, which is equipped with a burner section 3a and a boiler section 3b to heat a solution that has absorbed a refrigerant and generate high-temperature, high-pressure refrigerant vapor.

Reference numeral 4 denotes a low-temperature regenerator, which is equipped with a heating tube 4a and condenses the refrigerant vapor from the high-temperature regenerator 3 by spraying a solution thereon.

A condenser 5 is provided with a cooling water pipe 5a indicated by a broken arrow, and is used to condense the refrigerant vapor generated in the low-temperature regenerator 4.

6.8 is a solution pump, 10 is a refrigerant pump, 11° and 12 are low temperature and cylinder heat exchangers, and the above-mentioned absorption cycle operating equipment is connected by refrigerant piping and solution piping, although no particular code is attached. A multi-effect absorption refrigerator is constructed. Arrows along the piping in the figure indicate the flow of refrigerant or solution.

When producing chilled water (during cooling operation) in the multi-effect absorption chiller configured as described above, the cooling/heating switching valve 15 is closed, and the refrigerant is sprayed from the spray header 9 onto the cold water pipe la of the evaporator 1 and evaporated. and sends this refrigerant gas to the absorber 2. On the other hand, during hot water production (during heating operation), the cooling/heating switching valve 15 is opened to send the refrigerant to the absorber 2 and mix it with the solution.

Next, details of the high temperature regenerator 3 will be explained with reference to FIG.

The high temperature regenerator 3 consists of a burner section 3a and a boiler section 3b. First, the configuration of the burner section 3a will be explained.

21 is a burner case, 22a is a mixing chamber for premixing fuel gas and primary air, 22b is a line-shaped boat part, 22
C is the flame mouth surface. 24 is a rectifier plate, which serves as a secondary air flow path 24.
I am able to compensate for a. A partition wall 25 is provided with a linear aperture 25a through which the flame 23 flows. A primary combustion chamber 26 is formed between the rectifier plate 24 and the partition wall 25.

A tertiary air chamber 30 is formed at the top of the burner case 21, and a secondary combustion chamber 27 is formed which communicates with the tertiary air chamber 30 through a tertiary air outlet 29 provided in the tertiary air chamber 30. The burner end plate 28 is in contact with the burner end plate 3b.

On the other hand, the boiler section 3b includes a tertiary combustion chamber 31 provided on the burner section 3a and communicating with the secondary combustion chamber 27, a solution tube group 32 disposed downstream of the tertiary combustion chamber 31, and the tertiary combustion chamber 31. Solution chamber 3 surrounding combustion chamber 31 and solution tube group 32
3, this solution chamber 33 is formed by the boiler end plate 34, which is connected to the burner end plate z8, and the inner and outer walls 35, 36.

The conventional high temperature regenerator 3 having such a structure has (1)
- Since the secondary air ratio is low and combustion is completed using secondary air and tertiary air, various gases and gasified kerosene can be used as fuel. (2) The combustion chamber load can be increased to about 2.5 times compared to the conventional one, and the tertiary combustion chamber 3
1 can be made smaller, the high temperature regenerator can be made more compact.

Therefore, there are advantages in that the amount of expensive solution can be reduced and the time required for startup can be shortened accordingly.

However, the high temperature regenerator 3 has the following drawbacks. That is, the high temperature (1
Heat from the combustion gas (approximately 300 to 1500 C) is transferred to the wall 27a of the secondary combustion chamber 27 by radiation and convection. This heat is transferred to the solution in the solution chamber 33 via the secondary combustion chamber wall 27a, the burner end plate 28 and the boiler end plate 34, so in order to maintain such heat transfer, the secondary combustion chamber wall 27a is The temperature becomes high. The temperature of the solution increases as the absorption refrigerator becomes more multi-effect, so as the order of effect increases, the temperature of the secondary combustion chamber wall 27 also becomes higher.

For example, assume that the burner section 3a and the boiler section 3b are made of aluminum and iron, respectively, and the burner end plate 28 and the boiler end plate 34 are fixed with bolts.

In the case of double effect, the temperature of the solution is about 150 C, and if the burner heat input is 30.000 kcal/h, the amount of heat flowing from the secondary combustion chamber 27 to the secondary combustion chamber wall 27a is about 1000 kcal/h. The temperature of the secondary combustion chamber wall is approximately 350 U, the temperature of the burner end plate is approximately 220 C, and the temperature of the boiler end plate is approximately 160 C. In triple effect, the solution temperature is about 210C, so the temperature of each part is 60C.
My throat gets high. As is clear from these facts, the secondary combustion chamber wall 27a reaches a very high temperature, which poses a problem in terms of heat resistance of aluminum. In addition, the burner end plate 28 and the boiler end plate 34
There was a problem in that thermal stress was generated at the joint between the boiler and burner due to the difference in coefficient of thermal expansion caused by the different materials of the boiler and burner, and there was a risk of fatigue failure.

[Purpose of the invention]

The purpose of the present invention is to solve the above-mentioned problems, prevent the burner from overheating, prevent the strength of the burner material from decreasing due to overheating and fatigue failure due to thermal stress, and prevent the burner from being lost from the high-temperature burner surface. [Summary of the Invention] The structure of the multi-effect absorption refrigerator according to the present invention is such that the refrigerant is evaporated. an evaporator that absorbs the evaporated refrigerant into a solution, and a burner section and a part of the boiler that heat the solution that has absorbed the refrigerant and generate high-temperature, high-pressure refrigerant vapor. A cycle is constructed by connecting a high-temperature regenerator equipped with a refrigerant, a low-temperature regenerator equipped with a heating tube that generates refrigerant by heating a solution with refrigerant vapor from the high-temperature regenerator, and a condenser that condenses the refrigerant vapor. In the multi-effect absorption refrigerator, a heat exchange section is provided connected to the burner section that heats a part of the boiler of the high temperature regenerator, and the heat exchange section is connected to the low temperature regenerator to circulate a refrigerant. It is constructed by disposing refrigerant pipes to

Furthermore, in the present invention, the molten K in the high temperature regenerator
By circulating a liquid refrigerant with a lower boiling point in the boiler mounting area of the burner, the burner is cooled and the burner is prevented from overheating, thereby preventing the generation of thermal stress. It was designed to recover the heat that was lost from the

[Embodiment of the Invention] An embodiment of the present invention will be described below with reference to FIGS. 3 and 4.

FIG. 3 is a block diagram of a multi-effect absorption refrigerator according to an embodiment of the present invention, and FIG. 4 is a sectional view of the high temperature regenerator section. .2 The parts with the same reference numerals as those in Fig. 2 are the same parts as in the prior art, so their explanation will be omitted.

In the figure, 4o is a heat exchanger, and the heat exchanger 4° is installed between the burner section 3a and the wheeler 3b, and has a refrigerant pipe 40a running inside. One of the refrigerant pipes 4o communicates with the inlet side of the heating pipe 4a in the low temperature regenerator 4 with a refrigerant pipe 41,
The other side communicates with the outlet side of the heating tube 4a through a refrigerant tube 42.

In the multi-effect absorption refrigerator configured in this way, the refrigerant vapor generated in the high temperature regenerator 3 is transferred to the heating pipe 4a of the low temperature regenerator 4.
After being condensed, part of the refrigerant is sent to the condenser 5 and the other part is sent to the heat exchanger 40 via the refrigerant pipe 42. The liquid refrigerant sent to the heat exchanger 40 evaporates while cooling the burner 3a, and returns to the low temperature regenerator 4 together with the steam generated in the still temperature regenerator 3 via the refrigerant pipe 41. High temperature regenerator 3 is low temperature regenerator 4
Since it is located at a low position, the heat exchanger 4 is connected from the heating pipe 4a.
Circulation to zero is driven by thermosiphoning. The evaporation temperature of the refrigerant in the heat exchanger 40 is about 95C, and the burner temperature can be lowered by about 550C compared to cooling the burner with a solution at about 150C as in the conventional example. This solves the problem of burner heat resistance and fatigue failure caused by thermal stress. In addition, the heat dissipated from the high-temperature burner surface is recovered into the liquid refrigerant, which leads to energy savings.In addition, if the heat exchanger 40 and burner 3a are made in one piece, contact thermal resistance is eliminated, which further cools the burner. It is more effective and the energy saving effect is also improved.

Next, another embodiment of the present invention will be explained as shown in FIG.
This will be explained with reference to the figures.

FIG. 5 is a sectional view of the high temperature regenerator section of a multi-effect absorption refrigerator according to another embodiment of the present invention.
Components with the same reference numerals as those in the drawings are the same parts as in the previous embodiment, so their explanation will be omitted.

In FIG. 5, 3C is a part of the boiler, and the boiler 3c is a once-through boiler consisting of a spirally wound solution heat transfer tube 37 and an outer wall 38. The solution is heated while flowing through the solution heat transfer tube 37 to separate the refrigerant vapor and send it to the low temperature regenerator.

The burner section 3a is similar to the embodiment shown in FIG.

43 is a refrigerant pipe arranged in contact with the burner end plate 28;
It is configured to remove heat from the burner. This refrigerant pipe 43 will be more effective as a heat exchanger if the contact surface with the burner is made flat (not shown) to increase the contact area.

Further, the refrigerant pipe 43 may be formed integrally with the burner section to improve heat transfer.

In the multi-effect absorption refrigerator configured in this way, the refrigerant condensed in the low-temperature regenerator is guided to the refrigerant pipe 43 to absorb heat from the burner, and then returned to the low-temperature regenerator again, as in the previous embodiment. , it is possible to prevent overheating of the burner and also perform heat recovery.

Further, in this embodiment, the structure of the boiler 3c is a once-through type, so it has an excellent pressure-resistant structure, and is suitable for use in a triple-effect machine where the pressure and temperature in the high-temperature regenerator are high.

In this case, the solution temperature is as high as 250C, so it is difficult to cool the burner.This embodiment, in which the burner is cooled using a liquid refrigerant, is very effective.

Furthermore, the once-through boiler has the effect of reducing the amount of solution sealed, saving the amount of solution, and improving the start-up characteristics of an absorption chiller.

〔Effect of the invention〕

As described above, according to the present invention, liquid refrigerant having a low boiling point, whether it is a solution or not, is circulated from the low-temperature regenerator and used to cool the burner, and the evaporated refrigerant is returned to the low-temperature regenerator, so that the burner It prevents overheating, prevents a decrease in strength due to overheating of the burner material, and prevents fatigue failure due to thermal stress. It also saves energy by recovering heat that would have been lost from the burner surface, which has reached a high temperature. There is an effect.

[Brief explanation of the drawing]

Figure 1 is a block diagram of a conventional multi-effect absorption chiller;
3 is a configuration diagram of a multi-effect absorption refrigerator according to an embodiment of the present invention. FIG. 4 is a sectional view of the high-temperature regenerator section. FIG. 5 is a sectional view of a high temperature regeneration section of a multi-effect absorption refrigerator according to another embodiment of the present invention. 1... Evaporator, 2... Absorber, 3... High temperature regenerator, 3a... Burner part, 3b... Boiler part, 3C.
... Once-through boiler, 4... Low temperature regenerator, 4a... Heating tube, 5... Condenser, 37... Solution heat transfer tube, 40...
...Heat exchanger, 40a. 41.42.43... Refrigerant pipe. ■ 1 Figure 2 Figure 4 Figure 5

Claims (1)

[Scope of Claims] 1. An evaporator that evaporates refrigerant to generate refrigeration capacity, an absorber that absorbs the entire solution of the evaporated refrigerant, and a solution that absorbs the refrigerant and heats it to generate refrigerant vapor at high temperature pressure. A high-temperature regenerator equipped with a burner section and a boiler section to generate refrigerant, a low-temperature regenerator equipped with a heating tube that heats a solution with refrigerant vapor from the high-temperature regenerator to generate refrigerant, and condenses the refrigerant vapor. In a multi-effect absorption refrigerator that is connected to a condenser to form a cycle, a heat exchange part is provided by joining to the burner part that heats a part of the boiler of the high temperature regenerator, and a heat exchange part is provided in the heat exchange part. A multi-effect absorption refrigerating machine, characterized in that it is configured by disposing a refrigerant pipe connected to the low-temperature regenerator to circulate refrigerant. 2. In the item described in claim 1, a heat exchanger is provided between the burner section of the high-temperature regenerator and a part of the boiler, and the heat exchanger is provided in contact with the burner section and the boiler section. A multi-effect absorption refrigerator in which a refrigerant pipe is installed in the refrigerant pipe, and both ends of the refrigerant pipe are communicated with the inlet and outlet sides of the heating pipe of the low-temperature regenerator. 3. In the item described in claim 1, a part of the boiler of the high-temperature regenerator is a once-through boiler with a built-in solution heat transfer tube, and a refrigerant tube is arranged so as to face or connect with the burner part. A multi-effect absorption refrigerator.