JPS5949465A - Heat pump type absorption cold and hot water machine - 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 The present invention includes an evaporator, an absorber, a regenerator, a condenser, a heat exchanger, and a pump that are not operated in series, and the cold water flowing to the evaporator is connected to a low-temperature heat source. This invention relates to a heat pump type absorption chiller/heater in which hot water is used as the cooling water that flows through an absorber and a condenser, and the heat is extracted to the outside.

A heat pump using a conventional single-effect absorption refrigerator is
In principle, there is no difference from absorption refrigerators used for general cooling purposes. Therefore, when extracting hot water of a level used for normal heating using well water or the like as a low-temperature heat source, it is possible to extract hot water of about 50C without any special measures.

However, when taking out hot water of 500C or more, the higher the hot water temperature is, the better, such as preheating boiler feed water, and for other purposes, for example, based on a low temperature heat source of about 30 to 35C. If you want to extract high-temperature water at 90C, in a normal -1 efficiency cycle, the highest temperature point and highest concentration point during the cycle will exceed the practical range, and the cycle will not be completed, and the heat source pressure is not high. It is so unsuitable for practical use.

A typical cycle system in this case is shown in FIG. 1, and a cycle diagram shown on the Dueling diagram is shown in FIG. 2, respectively. First, to explain the cycle with reference to FIG. 1, the refrigerant that is evaporated by taking heat from the low-temperature heat source water 2 in the evaporator 1 flows into the absorber 3, where it gives heat to the cooling water 4 flowing through the pipe and becomes a concentrated solution. be absorbed into. The dilute solution 5 that has absorbed the refrigerant is sent to a regeneration temperature 7 by a solution pump 6, where it is concentrated by a heating source 8 and separated into a concentrated solution 9 and refrigerant gas. The concentrated solution 9 is returned to the regenerator 3 to generate refrigerant gas. This refrigerant gas flows into the condenser 10, gives heat to the cooling water 4, and condenses.

It is liquefied and returned to the evaporator 1. In this evaporator 1, a pump 11 spreads refrigerant liquid over a group of tubes to improve heat transfer efficiency. Furthermore, a heat exchanger 12 is provided between the dilute solution and the concentrated solution to improve cycle efficiency.

In such a cycle, what determines the practical limit of use is the regenerator port temperature 15. The heating source pressure is 16 and the concentrated solution concentration is 17. In other words, if the regenerator inlet temperature is too high, the corrosivity of the solution will rapidly become noticeable, and if the heating source pressure is too high, the upper limit temperature of the hot water that can be obtained will be restricted due to constraints on the supply equipment, and the heat pump will not be able to function properly. will not be able to fully achieve its objectives. Furthermore, if the concentration of the concentrated solution is too high, crystals will form, so the upper limit temperature of hot water obtained from these three points is determined.

Further, according to FIG. 2, the lower the temperature of the low-temperature heat source water, the lower the evaporation temperature 13, and the higher the temperature of the hot water to be extracted, the higher the condensation temperature 14.
It can be seen that the larger the difference in 4, the higher the maximum temperature, concentration, and heating source pressure.

In such a normal -1 utility cycle, 30-35C
It is practically impossible to scale high-temperature water of 85 to 90C based on a low-temperature heat source of about 100℃. Note that in FIGS. 2 and 4, curve W is a water saturation line.

In view of the above, the present invention is based on a single-effect absorption cycle, and is intended to scale hot water at a high temperature (85-90C) with a low-level heating source, including an evaporator, an absorber, a regeneration temperature and a condensing temperature. Each device is divided into at least two parts via a partition wall, each of these divided devices is combined to form at least two independent single-effect absorption cycles, and cooling water (
The hot water is heated to a high temperature by flowing the hot water in the order of the first absorber, second absorber, second condenser, and first condenser.

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 3, la, lb, 3a, and 3b are an evaporator and an absorber divided into two by a partition wall 20, respectively;
One of the evaporators 1a and lb is a tube 22a through which low-temperature heat source water (cold water) flows.

22b group, and the other absorber 3a,
'3b is a tube 21a through which cooling water (hot water) 4 flows.
, '21b group, respectively. 7a
, 7b and 10a, 10b are a regenerator and a condenser, respectively, which are divided into two by a partition wall 20. One of the regenerators 7a, 7b is a tube 2 through which a heating source 8 such as steam flows.
3a and 23b groups, and the other condenser 10a
, 10b is a tube 24a through which cooling water (@water) 4 flows.
, and 24b groups, respectively.

6a is a solution pump that sends the dilute solution 5a in the absorber 3a to the regenerator 7a via the conduit 25a and the heat exchanger 12a;
The heat exchanger 12a functions to exchange heat between the dilute solution 5a and the concentrated solution 9a returned from the regenerator 7a to the absorber 3a. 6b connects the dilute solution 5b in the absorber 3b to the conduit 2.
5b and heat exchanger 12 b f: a solution pump that sends the solution to the regenerator 7b via which the heat exchanger 12L+ exchanges heat with the dilute solution 5b and the concentrated solution 9b that is returned from the regenerator 71 to the absorber 3b. It performs the action of causing 11 is an evaporator la;
This is a refrigerant pump that sprays refrigerant into the group of tubes 22a and 22b of Ib to promote evaporation.

Next, we will discuss the operation of this embodiment consisting of the above-mentioned structure.
explain.

Each set of absorber 3a and evaporator 1a and absorber 3b and evaporator 1b provided on both sides of partition wall 20 performs respective functions of absorption and evaporation independently, and also controls temperature of hot water 4 and cold water 2. Each set of absorber and evaporator has its own absorption and evaporation temperatures.

If flexural bending is performed, on the left side of the partition wall 20, the evaporator 1a on the side where the temperature of the cold water 2 is higher and the absorber 3a on the side where the temperature of the hot water 4 is lower are 1.
Even if the temperature of the hot water 4 flowing out from the group of tubes 21b of the absorber 3b on the right side of the partition wall 20 is high, the dilute solution 5a of the absorber 3a becomes sufficiently dilute.

Therefore, since the concentration of the dilute solution 5a flowing into the regenerator 7a provided on the left side of the partition wall 20 is low, the concentration of the concentrated solution 9a in the regenerator 7a also decreases, and the tube 2 of the condenser 10a
The temperature of the hot water 4 flowing out from the group 4a becomes higher than in the conventional case. Therefore, even if the condensation pressure in the condenser 10a increases, the saturation concentration of the concentrated solution 9a will be lower than in the conventional example, so even if the temperature of the heating source 8 supplied to the group of tubes 23a of the regenerator 7a is low, the refrigerant can be played.

On the other hand, on the right side of the partition wall 20, the evaporator 1b on the low temperature side of the cold water 2
Since the absorbers 3b on the high temperature side of the hot water 4 work together to evaporate and absorb the dilute solution 5b, the dilute solution 5b, which has a high concentration, is sent to the regenerator 7b via the pump 6b. Since the temperature of hot water 4 flowing through the group of tubes 24b built in the condenser 10b corresponding to the regenerator 7b is lower than that on the condenser 10a side, the condensation pressure decreases, and the temperature of the hot water 4 flowing through the group of tubes 24b built in the condenser 10b corresponding to the regenerator 7b decreases. The temperature level of the heating source 8 flowing into the regenerator 7 a Mu
It can be sufficiently heated and concentrated at the same level.

To explain the above-mentioned absorbing solution cycle with respect to the DJ diagram shown in FIG.
, lb are the evaporation temperatures, C and 2 are the condensers 10b and 1, respectively.
0a is the condensation temperature, a and b are the absorption liquid temperatures of the absorbers 3a and 3b, respectively, and C is the absorption liquid outlet temperature of the regenerators 7a and 7b. The concentration of the absorption liquid increases in the direction of arrow E.

The dilute solution 5a in the absorber 3a is indicated by point A from the evaporation temperature a and the absorption liquid temperature a, and the dilute solution 5b in the absorber 3b is similarly indicated by point C. It can be understood from this that the former dilute solution 5a is apparently much thinner than the latter dilute solution 5b. In order to send this thin dilute solution 5a to the regenerator 7a, even if the temperature of the hot water in the condenser 10a becomes high and the condensation temperature becomes -, the temperature of the concentrated solution 9a remains at point C relative to point B. . Therefore, it can be seen that the solution can be sufficiently heated and concentrated if the heating source 8 supplied to the group of tubes 23a built in the regenerator 7a is a few degrees higher than the temperature of the concentrated solution 9a.

On the other hand, point C indicating the dilute solution 5b in the absorber 3b is
It can be seen that the concentration is better than point A, which indicates the dilute solution 5a of a. In order to send this highly concentrated dilute solution 5b to the regenerator 7b, the temperature of the hot water flowing through the group of tubes 24b of the condenser 10b becomes lower on the condenser 10a side, so the condensation temperature of the condenser 10b becomes 2. For this reason, the temperature of the concentrated solution 9b becomes equal to point C relative to point D, so it is understood that it is sufficient for the heating source 8 to have the same temperature d as that of the heating source on the regenerator 9a side.

In addition, the concentration width of the absorption solution cycle formed by the absorber 3a and the regenerator 7a and the absorber 3b and the regenerator 7b is reduced,
Then, points A and B and points C and D will approach each other, and the concentration at point C will decrease, so it can be seen that even higher hot water temperatures can be handled.

In the second embodiment shown in FIG. 5, cold water 2 is introduced into a group of tubes 22b built in the evaporator 1b as shown by the arrow, and then introduced into a group of tubes 22a built in the evaporator 1a. This is different from the first embodiment shown in FIG.
Since the other structures are the same, their explanation will be omitted. In this example, the inlet temperature of the cold water 2 is high and the flow @
It is suitable when there is little. In addition, if the tubes 21a and 21b groups and the hot water flow rate are set so that the relationship between the solution concentrations in the absorbers 3a and 3b is optimal for the solution 6H determined by the temperature of the hot water 4, the overall solution concentration will decrease. , there is an advantage that the temperature of the heating source 8 can be lowered.

The third embodiment shown in FIG. 6 differs from the first embodiment in that the partition wall 20 between the evaporators 1a and 1b of the first embodiment shown in FIG. 3 is removed and a single evaporator 1 is formed. Since the other structures are the same as those of the first embodiment, their explanation will be omitted. Although the third embodiment has been described with reference to the case where cold water is used, the invention is not limited to this, and it goes without saying that the same effect can be obtained when the water is divided into n parts.

As explained above, according to the present invention, the larger the temperature range of the cooling water (hot water), that is, the temperature difference between the inlet of the first absorber and the outlet of the n-th condenser, the more remarkable the effect can be exhibited. Furthermore, when the temperature range of cold water (low-temperature heat source water) is wide, the solution concentration can be further reduced by combining an evaporator on the high IM side and an absorber on the low temperature side. Furthermore, when the temperature range of the hot water is wide, by dividing each device into multiple stages, the hot water temperature can be raised to an even higher temperature n, and the energy saving effect can be improved.

[Brief explanation of the drawing]

Figures 1 and 2 show a system diagram and Dueling diagram of a conventional heat pump type absorption chiller/heater, and Figures 3, 5, and 6 show an embodiment of the heat pump type absorption chiller/heater of the present invention. The system diagram, FIG. 4, is a Düring diagram of the absorption solution cycle of FIG. la, 1b°" 1st. 2nd evaporator, 2...cold water, 3a
. 3b... 1st. Second absorber, 4...Cooling water, 7a. 7 b... 1st. 2nd regenerator, 10a, 1Ob - 1st degree flat 1 Figure '￥3 z Figure 1 dirty Figure 4 army 5 Figure n

Claims (1)

[Claims] 1. An evaporator, an absorber, a regenerator, a condenser, a heat exchanger, and a pump are operatively connected, and the cold water flowing through the evaporator is used as a low-temperature heat source, and the absorber and condenser are connected together. In a heat pump type absorption chiller/heater in which the cooling water flowing through the vessel is hot water and the heat is extracted to the outside, the evaporator, absorber, regenerator, and condenser are each divided into at least two parts via a partition, and these The divided devices are combined to form at least two independent absorption solution cycles, and the cold water is transferred from the one with the highest temperature to the first evaporator. The cooling water is passed through the second evaporator in order, and the cooling water is passed in order from the lowest temperature to the first absorber and then the second absorber, and then passes through the second condenser and starts from the first condenser to the highest temperature. A heat pump type absorption chiller/heater characterized by being configured so that the cooled water flows out. 2. Pass the cold water from the low temperature heat source through the highest temperature cooling water i
Claims characterized in that the cold water at the lowest temperature is configured to flow into the evaporator corresponding to the absorber through which the cold water flows and the lowest temperature cold water flows out from the evaporator corresponding to the absorber through which the lowest temperature cooling water flows. The heat pump type absorption chiller/heater according to item 1. 3. The heat pump absorption cooling system according to claim 1 or 2, wherein the first evaporator and the second evaporator are configured as one evaporator by removing the partition wall of the evaporator. Water machine. 4. Cold water at multiple temperature levels is passed through the evaporators in the same section, and the evaporation pressure is configured to have the most desirable relationship with the absorption liquid concentration in that section and the cooling water temperature. A heat pump type absorption chiller/heater according to any one of claims 1 to 3.