JPH0316588B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a refrigerant rectification device used as a means for varying the refrigerant composition of a heat pump device using a non-azeotropic mixed refrigerant.

Prior Art Conventional refrigerant rectifiers used in heat pump devices using non-azeotropic mixed refrigerants include, for example, a second
There is one shown in the figure. In FIG. 2, 1 is a refrigerant rectification column, 2 is a top reservoir, 3 is a bottom reservoir, 4 is a cooling source, 5 is a heating source, 6 is a low boiling point refrigerant liquid, 7 is a high boiling point refrigerant liquid, 8 and 9 are pipes connecting the tower top reservoir 2 and the refrigerant rectification column 1, and 10 is an extraction pipe for extracting the low boiling point refrigerant liquid 6 or the high boiling point refrigerant liquid 7, and each of them is connected to the main circuit of the heat pump device. Directs refrigerant liquid. 11
Conversely, it is an inlet pipe that leads the refrigerant from the main circuit of the heat pump device to the refrigerant rectification column 1. 12 is a refrigerant liquid falling inside the refrigerant rectification column 1, and 13 is a refrigerant gas rising therein. Reference numeral 14 denotes a filler filled in the refrigerant rectification column 1.

In the above configuration, the operation is as follows. The low boiling point components in the high boiling point refrigerant liquid 7 are boiled by the heating source 5, and the gas components rise within the refrigerant rectification column 1. On the other hand, the high boiling point components in the low boiling point refrigerant liquid 6 pass through the pipe 8 and descend within the refrigerant rectification column 1 . A filler 14 is filled in the refrigerant rectification column 1 . Here, the rising refrigerant gas 13 and the falling refrigerant liquid 12 exchange heat on the surface of the filler 14, and as the rising refrigerant gas 13 rises in the refrigerant rectification column 1, the lower boiling point components The resulting gas is liquefied by the cooling source 4 through the pipe 9, and becomes a liquid rich in low-boiling components, which accumulates in the top reservoir 2. Furthermore, the descending refrigerant liquid 12 is
Similarly, as the liquid descends due to heat exchange, the liquid becomes richer in high-boiling components and accumulates in the bottom reservoir 3.
Therefore, the refrigerant is introduced from the main circuit of the heat pump device through the extraction pipe 11, and the introduced refrigerant is separated into a high boiling point refrigerant liquid and a low boiling point refrigerant liquid and stored by causing the above action. Depending on the needs of the main circuit, the high boiling point refrigerant liquid 7 or the low boiling point refrigerant liquid 6 can be returned to the main circuit through the extraction pipe 10, allowing a refrigerant of a desired composition to flow through the main circuit of the heat pump device. can be changed to

Problems to be Solved by the Invention In the refrigerant rectification device for a heat pump, there are both the gas rising in the refrigerant rectification column and the liquid flowing down, and the flows of these two are completely opposite. Therefore, if the rising amount of gas (or gas flow rate) becomes significantly large, a so-called flattening phenomenon occurs, which obstructs the flow of liquid that should be falling. This often occurs when the amount of heat from the heating source is extremely large, and when this phenomenon occurs, the refrigerant rectifier no longer functions as it should, and the refrigerant liquid is separated into low-boiling point and high-boiling point refrigerant liquids, which cannot be stored. There was a problem.

Therefore, an object of the present invention is to provide a refrigerant rectifying device for a heat pump that has an extremely simple configuration and prevents the flooding phenomenon, which has been a problem in the past, while maintaining the original function of the refrigerant rectifying device. do.

Means for Solving the Problems The technical means of the present invention for solving the above problems are as follows:
A compartment with a variable volume is provided in each of the tower top reservoir and the tower bottom reservoir, and each compartment is connected with piping so that the fluid inside the compartment can go back and forth between the compartments. It is something.

Effect According to the above configuration, when the pressure inside the tower bottom reservoir fluctuates during stable operation, the volume of the compartment in the tower bottom reservoir changes suddenly, and the internal fluid flows through the piping to the top of the tower. By flowing into the compartment in the reservoir or into the bottom reservoir, the volume of the compartment in the top reservoir changes suddenly, and the internal pressure increases to the level in the compartment in the bottom reservoir. It settles down when it balances the pressure. At this time, the pressure in the top reservoir and the pressure in the bottom reservoir are the same as before the pressure fluctuation occurs.
It is well balanced and allows stable operation at all times.

Embodiment FIG. 1 is a configuration diagram showing an embodiment of a refrigerant rectification device for a heat pump according to the present invention. Each component numbered 15 to 28 in FIG. 1 corresponds to each component numbered 1 to 14 in FIG. 2,
have the same functionality. 29 is a lower compartment with a variable volume provided in the bottom reservoir 17, and the fluid 3 is contained therein.
It contains 0. 31 is an upper compartment with a variable volume provided in the top reservoir 16, and a lower compartment 29
and the upper compartment 31 are connected by a pipe 32 and a fluid 30
It is now possible to come and go.

The functions of the refrigerant rectifying apparatus constructed as described above, particularly the function of preventing the occurrence of flooding, will be explained. The basic explanation of operating the refrigerant rectifier to separate and store low-boiling point refrigerant liquid and high-boiling point refrigerant liquid is the same as in the conventional example.

The high boiling point refrigerant liquid heated by the heating source 19 boils, and the generated low boiling point component gas rises through the space between the packing materials 28 in the refrigerant distillation tower 15 and reaches the top reservoir 1.
The refrigerant liquid 26 flows oppositely from the refrigerant liquid 26 falling through the pipe 22 from the refrigerant 6 . If the refrigerant gas 27 rises in large quantities, the refrigerant liquid 26 that should fall
However, it becomes difficult to overcome the rising gas and fall, and it rises together with the refrigerant gas 27,
Eventually, no liquid will fall from the top reservoir 16. A so-called flattening phenomenon occurs. When this phenomenon occurs, the refrigerant gas 27
It is known that the difference between the pressure inside the tower top reservoir 26 and the pressure inside the tower bottom reservoir 17 suddenly becomes large because the amount of gas generated becomes large. That is, as shown in FIG. 3, if the refrigerant gas flow rate in the refrigerant rectification column 15 is plotted on the horizontal axis, and the pressure difference between the pressure in the top reservoir 16 and the pressure in the bottom reservoir 17 is plotted on the vertical axis, then , there is a point P where the differential pressure suddenly increases with respect to the gas flow rate, and this is generally called the flattening point. Further, point Q is called a loading point, and is a point before the differential pressure increases. (Reference “Distillation Engineering Handbook” P374
Written by Shiro Sano). The refrigerant rectification column operates normally in the region to the left of point P, preferably in the region to the left of point Q. In this region, the pressure inside the tower top reservoir 16 and the inside pressure in the bottom reservoir 17 are The differential pressure is very small, and the change in differential pressure with respect to changes in gas flow rate is also small. Therefore, when the refrigerant rectification tower is operating normally, the lower compartment 29 and the upper compartment 31 hardly move due to their own tension, and the fluid 30 inside them does not move either. On the other hand, if an abnormality occurs in the refrigerant rectification tower and a large amount of refrigerant gas 27 is generated, the gas flow rate increases and the third
When reaching point Q in the figure, the differential pressure suddenly increases to point P. At this time, rather than self-tension, the top reservoir 17
The pressure difference between the internal pressure and the pressure of the fluid 30 becomes larger, and the lower compartment 29 contracts in the direction of decreasing its volume (in the direction of the arrow in FIG. 1). Accordingly, the internal fluid 30 passes through the pipe 32 to the upper compartment 31.
The upper compartment 31 expands in the direction of increasing its volume (in the direction of the arrow in FIG. 1), and stops when the internal pressure of the upper compartment 31 and the internal pressure of the lower compartment 29 are balanced. Due to this movement of the upper compartment 31, the actual volume inside the tower top reservoir 16 (excluding the upper compartment 31) decreases, and the pressure inside the tower top reservoir 16 becomes lower than that during normal operation. increases. Therefore, the velocity of the refrigerant gas rising through the pipe 23 decreases rapidly, and the low boiling point refrigerant liquid 20
As the liquid level of the refrigerant 20 tends to decrease, the low boiling point refrigerant liquid 20 rapidly falls through the pipe 22. The fallen liquid overcomes the rising refrigerant gas whose velocity has decreased and accumulates in the tower bottom reservoir 17 without difficulty.
By doing this, in the tower bottom reservoir 17,
The temperature of the high-boiling refrigerant liquid, which is actively generating refrigerant gas, drops, suppressing boiling, and returning to normal operation. When the operation is normal, the pressure difference between the pressure inside the tower bottom reservoir 17 and the pressure inside the tower top reservoir 16 is reduced.
This time, the fluid 30 moves in the opposite direction from the upper compartment 31 to the lower compartment 29 through the pipe 32 and returns to its normal position with the pressure balanced. Due to this effect,
The refrigerant rectification column can always be kept in stable operation.

Effects of the Invention As described above, the refrigerant rectifying device for a heat pump of the present invention includes an upper compartment and a lower compartment whose volumes are variable in the top reservoir and the bottom reservoir. By connecting the refrigerant rectifiers with piping to allow the internal fluid to flow, it is possible to prevent the problem of flooding, which is common in conventional refrigerant rectification equipment, with an extremely simple configuration, and the refrigerant rectification equipment can be used at all times. It has the effect of allowing stable and normal operation.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of a refrigerant rectifier for a heat pump according to an embodiment of the present invention, Fig. 2 is a block diagram of a conventional refrigerant rectifier for a heat pump, and Fig. 3 is a flow rate of gas in the refrigerant rectifier. FIG. 2 is a characteristic diagram showing the relationship between the pressure inside the tower top reservoir and the pressure inside the bottom reservoir. 1,15...Refrigerant rectification column, 2,16...Tower top reservoir, 3,17...Tower bottom reservoir, 12,26...
Refrigerant liquid, 13, 27... Refrigerant gas, 29... Lower compartment, 30... Fluid, 31... Upper compartment, 32...
…Piping.

Claims (1)

[Claims] 1. A tower top reservoir for storing a low boiling point refrigerant, a tower bottom reservoir for storing a high boiling point refrigerant, an upper part connected to the tower top reservoir, and a lower part connected to the tower bottom reservoir,
a refrigerant rectification column having piping into which a low-boiling point refrigerant, a high-boiling point refrigerant, or a mixed refrigerant thereof flows in; an upper compartment with a variable volume is provided in the tower top reservoir; A refrigerant rectifying device for a heat pump, which has a variable lower compartment and connects the upper compartment and the lower compartment.