JPS6342181B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an absorption cooling/heating system that can be switched between a cooling cycle and a heating cycle using an absorption refrigeration system that performs an absorption refrigeration cycle using a refrigerant liquid and an absorption solution. .

In order to perform a heating cycle in a conventional absorption refrigeration system, such as a dual-effect absorption refrigeration system equipped with multiple generators, the cooling cycle and heating cycle can be performed by operating valves in the piping. In the heating cycle, it is known to directly input refrigerant vapor from a high temperature generator into a condenser to provide heat of condensation to hot water used for heating, and to operate by mixing refrigerant into a solution.

However, in an absorption refrigeration cycle, it is known that efficiency decreases as the flow rate of solution in and out of the high temperature generator increases, and that as the flow rate decreases, the concentration range increases and there is a risk of crystallization. For this reason, absorption refrigeration equipment is usually equipped with a flow rate control mechanism such as an orifice or a control valve to ensure a sufficient flow rate to prevent crystallization, and to limit the maximum flow rate to prevent a drop in efficiency.
It is set at around 1.1 to 1.3.

On the other hand, in the heating cycle, the heat from the heat source applied to the high-temperature generator is simply imparted to the hot water in the form of latent heat of the refrigerant vapor or sensible heat of the solution, and the formation coefficient is not affected by the solution flow rate. It is approximately 1.0. Therefore, assuming that the refrigeration capacity and the heating capacity are equal in terms of calorific value, the amount of heat from the heat source added to the high-temperature generator during heating is approximately 1.1 to 1.3 times that during cooling. If the flow rate is approximately constant during cooling and heating, the concentration range in the high temperature generator will be too large during heating, and there is a risk of crystallization. Particularly in a cycle in which a dilute solution is distributed between a high temperature generator and a low temperature generator (so-called parallel flow cycle), the concentration range in the high temperature generator becomes too large and there is a great risk of crystallization at the outlet of the high temperature generator. Become.

For this reason, in conventional absorption heating and cooling systems, in order to avoid crystals during heating, the solution flow rate is increased to match the heating time (by increasing the flow rate,
Efficiency during cooling decreases. ) Alternatively, heating and cooling equipment has been equipped with a large refrigerant tank, and the refrigerant is stored in this tank during operation during cooling, and this refrigerant is used during heating to reduce the concentration of the cycle.

The present invention aims to appropriately eliminate these conventional inconveniences, and aims to safely operate the solution by completely eliminating crystallization of the solution during the heating cycle by increasing the flow rate into and out of the high temperature generator during heating. The object of the present invention is to provide a heating and cooling device that can improve the efficiency of both heating and cooling cycles.

The present invention provides a high temperature generator, a low temperature generator, a condenser,
In a device that performs a cooling cycle and a heating cycle, comprising a mechanism that connects an evaporator, an absorber, a low-temperature heat exchanger, and a high-temperature heat exchanger to form an absorption refrigeration cycle, and an air conditioning/heating switching mechanism in the piping. In order to make the amount of solution flowing in and out of the high temperature generator during the heating cycle larger than the solution flow rate during cooling, the liquid from the high temperature generator is connected to the solution pipe connected to the high temperature heat exchanger on the inflow side of the high temperature generator. A solution piping provided with a float valve operated by surface fluctuation and flowing out from the high temperature generator and guided to the heating side of the low temperature generator or the low temperature heat exchanger, and a throttling device provided in the solution piping; It is characterized by comprising a bypass pipe that bypasses the throttle device and guides the bypass solution to a solution system path from the high temperature generator to the absorber, and further includes a flow rate control valve provided in the bypass pipe. .

Another important feature of the present invention is that, in combination with the above features, an auxiliary bypass line with a valve is provided to divert the dilute solution from the absorber during the heating cycle to the float valve and the throttle device in the solution delivery line. It is characterized in that it is bypassed and led to a high temperature generator or both to a low temperature generator.

To explain the present invention with reference to the drawings, a high temperature generator 1, a low temperature generator 2, a condenser 3, an evaporator 4, an absorber 5, a low temperature heat exchanger 6, and a high temperature heat exchanger 7 are connected by piping. In a device that performs a cooling cycle and a heating cycle by providing a mechanism for configuring an absorption refrigeration cycle and heating/cooling switching mechanisms 8 and 9 in the piping, condensed water drawn out from the condenser 3 and entering the evaporator 4 is provided. A valve 8 is provided in the liquid return pipe 18, and one end of a refrigerant liquid bypass pipe 19 having a valve 9 is connected to the return pipe 18, and the other end is connected to a system line and/or a low temperature generator 2 connected to the low temperature generator 2. It is directly connected to vessel 2.

Then, by opening the valve 8 and closing the valve 9, the cooling cycle is performed. That is, the dilute solution is transferred to a low temperature heat exchanger 6 and a high temperature heat exchanger 7 by a solution pump 25.
The liquid is sent to the high temperature generator 1, where it is heated to a high temperature, releases refrigerant vapor, and is concentrated to form an intermediate solution. This solution enters the high temperature heat exchanger 7, where its temperature is lowered by heat exchange with the dilute solution from the absorber 5, and then enters the low temperature generator 2 where it is heated by the refrigerant vapor previously generated in the high temperature generator 1. As it is heated, more refrigerant vapor is released and the solution increases in concentration to become a concentrated solution.

On the other hand, the refrigerant vapor generated in the low temperature generator 2 enters the condenser 3, where it is cooled by cooling water and condensed.
Further, the refrigerant vapor generated in the high temperature generator 1 is also condensed by heat exchange with the solution in the low temperature generator 2 and enters the condenser 3. The refrigerant accumulated in the condenser 3 is transferred to the condensate return pipe 18
The water passes through the valve 8 and returns to the evaporator 4. Further, the concentrated solution leaving the low temperature generator 2 passes through a pipe 16, exchanges heat with the dilute solution in a low temperature heat exchanger 6, enters an absorber 5, and enters an absorber tube 5, which is a heat transfer tube through which cooling water passes. ’ group is sprayed. The sprayed concentrated solution is cooled by cooling water and passed through the evaporator 4.
It absorbs the evaporated refrigerant vapor and becomes a dilute solution.
In this evaporator 4, heat is removed from the cold water by evaporation of the refrigerant, and the temperature becomes low. The dilute solution was prepared as described above.
It is sent to the high temperature generator 1 via the low temperature heat exchanger 6 and the high temperature heat exchanger 7, and performs a cooling cycle.

Further, during the heating cycle, the valve 8 is closed, the valve 9 is opened, and the refrigerant liquid accumulated in the condenser 3 is introduced into the low temperature generator 2. The solution leaving the low temperature generator 2 passes through the low temperature heat exchanger 6 and enters the absorber 5, giving heat to the cooling water (hot water). In this case, the solution concentration in the low temperature generator 2 becomes low, and due to the decrease in concentration, the generated vapor pressure becomes high, and the condensation temperature increases. Therefore, the temperature of the cooling water (hot water) coming out of the condenser 3 becomes high and can be used for heating or the like.

In the apparatus of the present invention, as shown in FIG. 1, in order to make the amount of solution flowing in and out of the high temperature generator 1 during the heating cycle larger than the solution flow rate during cooling, the solution pipe 10 on the inflow side of the high temperature generator 1 is heated. A float valve 12 is provided in the solution path connected to the heat exchanger 7, which is operated by fluctuations in the liquid level in the high temperature generator 1, and the solution flows out from the high temperature generator 1 and flows into the low temperature generator 2.
The solution return pipe 11 guided to the solution return pipe 11, the throttle device 13 provided on the solution return pipe 11, and the throttle device 13 are bypassed, and the bypass solution is guided to the solution system path from the high temperature generator 1 to the absorber 5. Furthermore, since the bypass pipe 15 is provided with a flow control valve 14, even if the float valve 12 is used to maintain the liquid level of the high temperature generator 1 at a substantially constant level, for example, the valve 14 of the bypass pipe 15 can be By opening it, the amount of solution sent to the high temperature generator 1 can be increased compared to when cooling, increasing the amount of solution in the high temperature generator 1, reducing the concentration range in the high temperature generator 1, and mixing the refrigerant into the solution. Even with this method, there is no need to worry about crystals since there is only one outlet from the high temperature generator.

The valve 14 of the bypass pipe 15 is fully opened during heating, but it can also be slightly opened, while it can be fully closed or slightly closed during cooling.

In the embodiment shown in FIG. 1, for example, an orifice, a regulating orifice, or a regulating valve is used as the throttle device 13 of the solution return pipe 11 of the high temperature generator 1, and a bypass pipe 15 is provided to bypass this. The position is preferably below the float part 12' of the float valve 12, and its end point is on the downstream side of the throttle device 13, as shown by the dotted line, in the low temperature generator 2 or in the solution piping before and after the low temperature generator. In any case, the flow rate of solution into and out of the high temperature generator 1 can be increased to enable effective operation.

The bypass piping 15 can bypass both the heating side of the high temperature heat exchanger 7 and the heating side of the low temperature heat exchanger 6, or can bypass either one of them, as appropriate, as shown in each embodiment below. It can also be linked to a valid location.

Also, although a configuration in which the refrigerant is mixed into the solution for the heating cycle is shown using valves 8, 9 and piping 18, 19, other connection configurations can be selected, or a configuration in which the refrigerant is not mixed in is also possible. It is possible.

In the figure, 1' and 2' are generator tubes, 3' is a condenser tube, 4' is an evaporator tube, 5' is an absorber tube, 12' is a float, 17 is a solution reservoir, and 20
The pipe 21 that leads the dilute solution from the absorber 5 to the low temperature generator 2 is closed or nearly closed with a valve during heating.
24 is a refrigerant pump.

Although the specific example in FIG. 2 is an example of a parallel flow cycle, a throttle device 22 such as an orifice that restricts the flow rate flowing into the high temperature generator 1 is provided in the solution supply piping 10 in addition to the float valve 12. The bypass pipe 15 bypasses only the throttle device 13 in the solution return pipe 11 and bypasses the throttle device 22 in the solution supply pipe 10 and the low-temperature heat exchanger 6.
A pipe 20 is provided to guide the dilute solution to the low temperature generator 2 or the pipe 11 that enters the low temperature generator 2 from between the pipe 20 and the pipe 20 is provided with a valve 21 as necessary, and is used to throttle during heating, resulting in a parallel flow cycle. It's like this.

Note that when the amount of solution introduced to the high temperature generator 1 is increased in a parallel flow cycle, the flow rate of the solution pump 25 may increase and cavitation may occur.
By providing a valve 21 at 0 and closing or closing the valve completely during heating, it is possible to prevent this problem accurately.

In addition to the float valve 12, the embodiment of FIG. 7. This is an example in which a bypass pipe 10' with a valve 23 that bypasses one of the low-temperature heat exchangers 6 is provided in the solution supply pipe 10, and the valve 23 is closed during cooling and is opened during heating. Then, the flow rate during cooling and the flow rate passing through the valve 23 become the inflow amount to the high temperature generator 1 and act effectively.

In this case, the heat exchangers 6 and 7 are usually used for the purpose of recovering heat during cooling, and are designed with a flow rate during the cooling cycle, so increasing the flow rate during heating increases the flow velocity. Since this increases the pressure loss of the heat exchanger and makes it more susceptible to corrosion, consideration is being given to bypassing a large amount of the heat exchanger. This also applies to the heating side of the heat exchanger, and as shown in the figure, the bypass piping 15 may bypass the high temperature heat exchanger 7, and this heat exchanger bypass is used especially during the parallel flow cycle, that is, the cooling cycle. This is effective in a configuration in which a pipe 20 with a throttle device 21 is added to guide the dilute solution from the absorber 5 to the high temperature generator 1 and the low temperature generator 2.

Moreover, when the solution flowing into the inlet of high temperature generator 1 bypasses the heat exchanger, the temperature of the liquid entering high temperature generator 1 becomes lower and most of the heat from the high temperature generator heat source is obtained in the form of sensible heat. Concentration width (heating amount ≒
It is also useful in preventing the amount of heat input into the high temperature generator from becoming too large.

In addition, in the example shown in FIG. 4, in an absorption air conditioning system in which a dilute solution from an absorber is guided to a high temperature generator and a low temperature generator during the cooling cycle, the solution flowing into the high temperature generator 1 is passed through the float valve 12 and the high temperature heat exchanger. 7 is bypassed from between the low-temperature heat exchanger 6 and the high-temperature heat exchanger 7 to the low-temperature generator 2 by bypass piping 10 that leads to the high-temperature generator 1 from the line of the piping 20 with the flow rate control valve 21' bypassed to the low-temperature generator 2. ', and can be operated by a valve 23 in the bypass piping 10'.

In this case, the bypass pipe 15 as a bypass at the outlet of the high temperature generator 1 is connected to the high temperature generator 1 as shown in the figure.
Therefore, the high-temperature heat exchanger 7 and the expansion device 13 may be connected in a bypass manner, and if necessary, they can be connected above or below the liquid level of the normal high-temperature generator 1. In any case, the bypass piping 15 The flowing fluid can be vapor, liquid, or gas-liquid two-phase.

Furthermore, in this embodiment, as in the example shown in FIG. J type line 2 from low temperature generator 2 to absorber
It can also be connected to 6. In this example of connecting to the J-type line 26, the throttle mechanism 13, high-temperature heat exchanger 7, and low-temperature heat exchanger 6 are all bypassed, resulting in an effective configuration.

In each of the above embodiments, the cooling water (hot water) flows through the absorber 5 and then into the condenser 3 during the heating cycle.
In addition to the method of leading to , the condenser 3 may be placed first,
Furthermore, in order to obtain two systems of hot water, one system may be divided into one through the absorber 5 and one through the condenser 3. In particular, if a method is adopted in which the condenser 3 is passed first and then passed through the absorber 5, the pressure difference between the condenser 3 and the absorber 5 can be reduced, and the latent heat of the condenser 3 can be used to increase the temperature. It is convenient to be able to raise the temperature further by using the sensible heat of the absorber 5.

The valves 8 and 9 can be configured to be switched by a single three-way valve, or can be manually operated or automatically operated by a solenoid valve or the like. A part of the mixture can be mixed into the concentrated solution, and the location of the mixture can be selected not only in the generator body but also at an effective location in the circulation path. can also be mixed in the evaporator and then mixed into the solution.

The present invention relates to an absorption refrigeration system that performs both a cooling cycle and a heating cycle. In particular, in an absorption refrigeration system that performs a dual-effect cycle during cooling, the amount of solution flowing in and out of a high temperature generator during heating is adjusted to By setting the flow rate to be higher than the flow rate, the solution concentration width in the high temperature generator can be reduced, making it easy to eliminate problems caused by crystals, making it possible to operate with high efficiency, and making cooling or heating operations easier. It can be switched with a simple operation, ensures extremely stable operation, is easy to maintain, has no inconvenience in handling, and uses an absorption refrigerator exclusively for cooling to perform the heating cycle efficiently. This makes it possible to do this without requiring expensive equipment, and by including the low-temperature generator in the operating cycle during the winter, it eliminates problems caused by crystals that are likely to occur when the low-temperature generator is stopped in a dual-effect refrigerator. It can accurately prevent crystallization due to solution stoppage in this part during the heating cycle, guarantee safe switching operation at all times, and can be easily used in existing equipment, making it extremely versatile. It is useful in reducing the equipment cost and operating cost of the enrichment device.

[Brief explanation of drawings]

The drawings show embodiments of the present invention, with FIG. 1 being a system explanatory diagram, and FIGS. 2 to 4 being system explanatory diagrams of other embodiments. 1...High temperature generator, 2...Low temperature generator, 1', 2'...
Generator tube, 3... Condenser, 3'... Condenser tube, 4... Evaporator, 4'... Evaporator tube, 5...
Absorber, 5'...Absorber tube, 6...Low temperature heat exchanger, 7...High temperature heat exchanger, 8, 9...Air conditioning switching mechanism, 10...Solution supply piping, 10'...Bypass piping,
11...Solution return piping, 12...Float valve, 13...
Throttle mechanism, 14...Valve, 15...Bypass piping, 16
... Piping, 17... Solution reservoir, 18, 19... Piping, 20
...Piping, 21, 22... Throttle mechanism, 23... Flow rate control valve, 24... Refrigerant pump, 25... Solution pump, 26
...J type piping.

Claims (1)

[Claims] 1. High temperature generator, low temperature generator, condenser, evaporator,
In an apparatus that performs a cooling cycle and a heating cycle, the apparatus includes a mechanism that connects an absorber, a low-temperature heat exchanger, and a high-temperature heat exchanger to form an absorption refrigeration cycle, and an air-conditioning/heating switching mechanism in the piping to perform a cooling cycle and a heating cycle. In order to make the amount of solution flowing in and out of the high-temperature generator larger than the solution flow rate during cooling, a float valve is provided in the solution piping on the inflow side of the high-temperature generator, which is activated by fluctuations in the liquid level of the high-temperature generator. At the same time, a solution pipe that flows out from the high temperature generator and is guided to the low temperature generator or the low temperature heat exchanger heating side, a throttle device installed in this solution pipe, and a throttle device are bypassed, and the bypass solution is heated to a high temperature. 1. An absorption heating and cooling device comprising: a bypass pipe leading to a solution line from a generator to an absorber via a low-temperature generator; and further comprising a flow control valve disposed in the bypass pipe. 2. The absorption type according to claim 1, wherein the bypass pipe has a starting point connected to a solution pipe flowing out from a high temperature generator below the float part of the float valve or to an outlet part of the high temperature generator. Air conditioning equipment. 3. The absorption air-conditioning apparatus according to claim 1 or 2, wherein the bypass pipe has a starting point connected to a solution return pipe after exiting the high-temperature heat exchanger. 4 Claims in which the bypass piping is a piping that bypasses a throttling mechanism that limits the flow rate of the solution coming out of the high temperature generator, and is a piping that guides the bypassed solution to the low temperature generator. The absorption air-conditioning device according to item 1, item 2 or 3. 5. The bypass pipe is a pipe that bypasses a solution flow rate control mechanism that limits the flow rate of the solution coming out of the high temperature generator, and is a pipe that guides the bypassed solution to the absorber. Absorption type air-conditioning device according to the first, second, or third scope. 6. The bypass piping bypasses a solution flow rate control mechanism that limits the flow rate of the solution coming out of the high temperature generator, and absorbs some or all of the bypassed solution from the low temperature generator. The absorption type air-conditioning device according to claim 1, 2, 3, or 4, which is a pipe leading to a solution piping system to a container. 7. The bypass piping bypasses a solution flow rate control mechanism that limits the flow rate of the solution coming out of the high temperature generator, and allows the bypassed solution to flow into both the low temperature generator and the absorber. The absorption type air-conditioning device according to claim 1, 2, or 3, which is a distribution pipe. 8 High temperature generator, low temperature generator, condenser, evaporator,
A device that performs a cooling cycle and a heating cycle by comprising a mechanism that connects an absorber, a low-temperature heat exchanger, and a high-temperature heat exchanger to form an absorption refrigeration cycle through piping, and an air-conditioning/heating switching mechanism in the piping, which performs a cooling cycle and a heating cycle. In order to make the amount of solution flowing in and out of the high temperature generator during the cycle larger than the solution flow rate during cooling, a float valve that is operated by fluctuations in the liquid level of the high temperature generator is provided in the solution piping path on the inflow side, and the A solution pipe that flows out from the high temperature generator and is guided to the low temperature generator or low temperature heat exchanger heating side, a throttle device installed in this solution pipe, and a throttle device that is bypassed so that the bypass solution flows from the high temperature generator. The auxiliary system is equipped with a bypass pipe that leads to a solution system path that passes through a low-temperature generator and reaches an absorber, and further includes a flow rate control valve in the bypass pipe, and a valve that can be opened during heating in addition to the bypass pipe. An absorption air-conditioning system characterized in that a bypass pipe is provided in front of the throttle device in the solution supply pipe by bypassing the float valve and connected to the high temperature generator or the solution pipe flowing into the high temperature generator. 9. The absorber according to claim 8, wherein the auxiliary bypass pipe is a pipe that guides a part of the feed solution from at least one of the heated side of the low-temperature heat exchanger or the high-temperature heat exchanger to the high-temperature generator. type air conditioning system. 10. The absorber according to claim 8 or 9, wherein the auxiliary bypass pipe is a pipe that distributes the dilute solution on the heated side of the high-temperature heat exchanger to both a low-temperature generator and a high-temperature generator. type air conditioning system.