JPH0345088Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a non-condensable gas discharge device in an absorption heat pump. This extracts non-condensable gas including hydrogen gas and refrigerant vapor that remain in the absorber, and reuses the refrigerant vapor for heat recovery in the absorption heat pump. It is used in fields where wastewater is efficiently discharged to the outside.

[Prior art]

In an absorption heat pump that is composed of vacuum vessels such as an evaporator, absorber, regenerator, and condenser, water as a refrigerant and an aqueous lithium bromide solution as an absorption liquid are circulated in the form of liquid or refrigerant vapor. This allows hot water or steam to be obtained in the absorber. In such an absorption heat pump, the internal pressure of the evaporator and absorber is approximately 500 mmHg, and the internal pressure of the regenerator and condenser is approximately 40 mmHg. Therefore, although airtightness is achieved by welding, etc., a small amount of air may still get in.
An iron vacuum container is oxidized by the moisture in the refrigerant and absorption liquid, forming an oxide film. The hydrogen gas generated at this time and the air that enters are noncondensable gases and remain in the vacuum container. Among them, the non-condensable gas in the evaporator is introduced into the absorber together with the refrigerant vapor,
It collects in the tube bank along with the non-condensable gases of the absorber. Further, as described above, the non-condensable gas in the regenerator is introduced into the condenser together with the refrigerant vapor and collects in the tube group of the condenser. These non-condensable gases significantly reduce the heat recovery ability in the tube group of the absorber, and also cause a significant decrease in the heat transfer effect in the tube group of the condenser. Therefore, in order to discharge such non-condensable gases to the outside, conventional absorption heat pumps focus on the fact that the internal pressure of the absorber is higher than that of the condenser, and remove all the non-condensable gases from the condenser. It accumulates in the air and is discharged as a mixture with refrigerant vapor using a bleed pump. However, when non-condensable gas and refrigerant vapor are delivered from the absorber to the condenser, the partial pressure of the refrigerant vapor is higher than the partial pressure of the non-condensable gas, so very little non-condensable gas is delivered, and most of the non-condensable gas is A phenomenon is occurring in which refrigerant vapor is extracted. When a large amount of refrigerant vapor is introduced into the condenser, this refrigerant vapor is cooled by cooling water in the condenser and becomes refrigerant liquid, which generates latent heat of condensation in the absorber, a function that should originally be recovered as thermal energy. I will not be able to fulfill my purpose. In other words, refrigerant vapor is generated in the evaporator and is introduced into the condenser as it is to become refrigerant liquid, which is simply repeated, resulting in heat loss without being recovered. In addition, there is a problem in that the partial pressure of the non-condensable gas in the absorber is lower than that of refrigerant vapor, making it difficult to extract.

[Purpose of invention]

This invention was developed to solve the above-mentioned problems, and it extracts the non-condensable gas and refrigerant vapor in the absorber, reuses the refrigerant vapor as thermal energy, and easily extracts the non-condensable gas. It is an object of the present invention to provide a non-condensable gas evacuation device in an absorption heat pump that can be used in an absorption heat pump.

[Structure of the idea]

The features of the present invention will be explained with reference to FIG. Heat is exchanged between the high-concentration absorbing liquid heading from the absorber 3 and the low-concentrating absorbing liquid heading from the absorber 3 to the regenerator 19, and the refrigerant liquid in the condenser 8 is transferred to the evaporator 9 by the transfer pump 18. This is an absorption heat pump that introduces the refrigerant vapor into the absorber 3 and recovers high-temperature heat in the absorber 3. is introduced from the condenser 8 to the evaporator 9.
A condensing chamber 6 is provided in which a part of the refrigerant liquid heading to the condensing chamber 6 flows in to condense the refrigerant vapor, and a throttle 13 is interposed in the introduction pipe 12 through which the noncondensable gas separated in the condensing chamber 6 is introduced into the condenser 8. The absorption heat pump is provided with a supply pipe 11 for supplying the refrigerant liquid that has passed through the condensation chamber 6 to the evaporator 9, and a reflux pipe 14 that returns the refrigerant liquid condensed in the condensation chamber 6 to the condenser 8. This is a non-condensable gas exhaust device.

〔Example〕

EMBODIMENT OF THE INVENTION Below, the absorption heat pump of this invention will be explained in detail based on the drawing which shows the Example.

FIG. 1 is a system diagram of an absorption heat pump 2 including a non-condensable gas discharge device 1, which is an embodiment of the present invention. The absorber 3 is provided with a pipe end of a lead-out pipe line 4 in a group of pipes from which non-condensable gas and refrigerant vapor can be led out. A constrictor 5 is interposed in the outlet conduit 4, and its tip is connected to a condensing chamber 6. This condensation chamber 6 is provided with an inflow pipe 7 through which a refrigerant liquid flows in to cool the introduced non-condensable gas and refrigerant vapor, and the other end is used to evaporate the refrigerant liquid in the condenser 8 using a transfer pump 18. Branch point 1 of pipe line 10 to be transferred to vessel 9
Connected to 0A. On the other hand, another branch point 10B of the pipe line 10 and the outlet of the refrigerant liquid after flowing through the condensing chamber 6 are connected by a supply pipe line 11. In addition,
This supply line 11 can also be connected directly to the evaporator 9 . One end of an introduction pipe 12 for introducing non-condensable gas into the condenser 8 is connected to the upper part 6A of the condensing chamber 6, and the other end is connected to the condenser 8 through a throttle 13 for reducing the pressure of the non-condensable gas. It is protruded into the tube group of. A reflux pipe 14 is provided at the bottom 6B of the condensing chamber 6 for refluxing the refrigerant liquid condensed in the condensing chamber 6 to the condenser 8, and the other end is connected to the vicinity of the liquid reservoir 8a of the condenser 8. In the tube group of the condenser 8, a tube end of a conduit 15 for leading out noncondensable gas and refrigerant vapor is provided. A bleed pump 16 for discharging non-condensable gas is interposed in this conduit 15.

According to such a configuration, it can be operated as follows.

The pressure inside absorber 3 and evaporator 9 is approximately 500mmHg,
The pressure inside the condenser 8 and the regenerator 19 is a vacuum of 40 mmHg, and non-condensable gases including air entering from the outside and hydrogen gas generated inside remain in the tube group. . Among these non-condensable gases, the non-condensable gas in the evaporator 9 is sent to the absorber 3 via a pipe 20, and the non-condensable gas in the regenerator 19 is sent to the condenser 8 via a pipe 21 as a refrigerant. Introduced with steam. Among them, the non-condensable gas having a low partial pressure and the refrigerant vapor having a high partial pressure introduced into the absorber 3 are depressurized by the restrictor 5 of the outlet pipe 4 to prevent only a large amount of refrigerant vapor from being drawn out. while gradually being introduced into the condensing chamber 6. On the other hand, a part of the refrigerant liquid heading from the condenser 8 to the evaporator 9 flows into the condensation chamber 6 from the branch point 10A of the pipe line 10 via the inlet pipe line 7. The above-mentioned non-condensable gas and refrigerant vapor are cooled by this refrigerant liquid, and their respective partial pressures become approximately equal to the low pressure within the condensing chamber 6. This non-condensable gas is introduced into the lower pressure condenser 8 through the introduction pipe 12 while being reduced in pressure by the throttle 13. The introduced non-condensable gas is discharged to the outside by a bleed pump 16 through a pipe 15 together with the non-condensable gas and refrigerant vapor remaining in the condenser 8 . The refrigerant vapor introduced into the condensing chamber 6 is cooled to refrigerant liquid, and its partial pressure is already equal to or lower than that of the non-condensable gas, so it is condensed without being discharged to the inlet pipe 12. and becomes a refrigerant liquid. As a result, the refrigerant liquid is returned to the liquid reservoir 8a of the condenser 8 via the return pipe line 14. The refrigerant liquid in the liquid reservoir 8a is transferred through the pipe line 10 by the transfer pump 18 and flows into the liquid reservoir 9a of the evaporator 9. At this time, a part of the refrigerant liquid is separated at the branch point 10A, and the above-described operation is performed in the condensing chamber 6. The refrigerant liquid leaving the condensing chamber 6 joins with the remaining refrigerant liquid transferred through the pipe line 10 via the supply pipe line 11 at a branch point 10B, and flows into the liquid reservoir 9a of the evaporator 9.

Note that if another condensing chamber (not shown) similar to the aforementioned condensing chamber 6 is provided upstream of the extraction pump 16 interposed in the conduit 15 of the condenser 8, non-condensable gas can be removed from the condenser 8 more efficiently. Can be discharged.

[Effect of idea]

As explained in detail above, the present invention, after extracting the non-condensable gas and refrigerant vapor accumulated in the absorber,
Non-condensable gas and refrigerant vapor are separated in the condensing chamber, and the refrigerant vapor is condensed into refrigerant liquid and reused as thermal energy, while the non-condensable gas is discharged from the condenser. As explained in the technical section, heat can be effectively recovered without directly cooling the refrigerant vapor drawn out from the absorber in the condenser. In addition, since non-condensable gas can be discharged, heat transfer in the tube group inside the vacuum container is improved and the amount of heat supplied from the outside can be used effectively. As a result, it becomes possible to increase the heat recovery of the absorption heat pump.

[Brief explanation of the drawing]

FIG. 1 is a system diagram of an absorption heat pump including the non-condensable gas discharge device of the present invention. 1... Non-condensable gas discharge device, 2... Absorption heat pump, 3... Absorber, 5, 13... Throttle, 6
... Condensation chamber, 8 ... Condenser, 9 ... Evaporator, 11
... Supply pipe line, 12... Introductory pipe line, 14... Return pipe line, 18... Transfer pump, 19... Regenerator.

Claims (1)

[Claims for Utility Model Registration] Waste heat is supplied to the evaporator and regenerator, cooling water is passed through the condenser, and a highly concentrated absorbent flows from the regenerator to the absorber and a concentrated absorbent flows from the absorber to the regenerator. An absorption heat pump that exchanges heat with an absorbing liquid with a low temperature, transfers the refrigerant liquid from the condenser to the evaporator using a transfer pump, introduces the refrigerant vapor generated in the evaporator to the absorber, and recovers high-temperature heat in the absorber. In this step, noncondensable gas containing hydrogen gas and refrigerant vapor remaining in the absorber are introduced through a throttle, and a part of the refrigerant liquid heading from the condenser to the evaporator is flowed in to condense the refrigerant vapor. A condensation chamber is installed to
A throttle is interposed in an introduction pipe for introducing the non-condensable gas separated in the condensing chamber into the condenser, and a supply pipe is provided for supplying the refrigerant liquid that has passed through the condensing chamber to the evaporator. 1. A non-condensable gas discharge device for an absorption heat pump, characterized in that a recirculation pipe is provided for recirculating the refrigerant liquid condensed in the condensing chamber to the condenser.