A dual-cycle exhaust heat recovery air conditioning system under combined normal and emergency conditions

Abstract

The utility model discloses a double-circulation exhaust heat recovery air conditioning system under hospital normal and emergency combined working conditions, including a first compressor, a first four-way valve, a fresh air heat exchanger, a first throttle valve, an exhaust heat exchanger, a second compressor, a second four-way valve, an indoor heat exchanger, a second throttle valve and an outdoor heat exchanger. Beneficial effects of the utility model: the utility model can meet the exhaust heat recovery needs under various working conditions, can recover the cold in the exhaust air in summer to deheat and dehumidify the fresh air, can recover the heat in the exhaust air in winter to heat the exhaust air, and has the function of defrosting by using the heat of the indoor exhaust air, can realize the recovery of sensible heat and latent heat while avoiding the defrosting model of conventional air conditioners such as electric heating and indoor heat absorption, and the recovery amount is fully adjustable within the range of 0 to 100%; it can realize the maximum utilization of fresh air for indoor air conditioning under both winter and summer working conditions, greatly reducing the energy consumption of the air conditioning system in both normal and epidemic conditions of the hospital.

Description

Technical Field

[0001] The present invention relates to the technical field of exhaust heat recovery heat pump air conditioning, and in particular to a double-circulation exhaust heat recovery air conditioning system under normal and emergency combined working conditions. Background Art

[0002] In hospital buildings, air conditioning consumes a huge amount of energy, accounting for 50% to 70% of the total energy consumption, which is about twice that of ordinary office buildings. Therefore, it is very necessary to take energy-saving measures for the hospital's air conditioning system. Among them, the fresh air load, as one of the components of the air conditioning load, generally accounts for 30% to 50% of the air conditioning load, and even exceeds 60% in winter, and even exceeds 70% in public buildings with a large population density. The use of exhaust heat recovery devices in the air conditioning system can recover and utilize the cold / heat contained in the exhaust air, pre-treat the fresh air, and thus reduce the energy consumption generated by processing the fresh air. Studies have shown that when the heat recovery efficiency of the heat recovery device reaches 70%, it can effectively reduce the heating energy consumption by 40% to 50%.

[0003] Compared with other public buildings, the air composition in hospital buildings is more complex. Some areas have high bacterial content, some areas have high concentrations of chemical pollutants, some areas have strong odors, and some areas even contain radioactive pollutants. It is a very special place. Emergency hospital buildings need to have good air flow direction and pressure gradient control. In addition, polluted gas exhaust and maintaining gas flow direction and pressure gradient control require a large amount of outdoor fresh air. Therefore, in hospital buildings, the fresh air volume and exhaust volume are relatively large, which provides conditions for the use of heat recovery systems to achieve good energy-saving effects. When selecting heat recovery devices, avoid using heat recovery devices that are prone to exhaust air infiltration pollution.

[0004] The main component of exhaust heat recovery in existing air conditioning systems is the heat exchanger, which mainly includes: it can be roughly divided into two categories: sensible heat recovery device and total heat recovery device. Sensible heat recovery devices can only recover sensible heat, and common ones include plate sensible heat heat exchangers, heat pipe heat exchangers and intermediate heat medium heat exchangers; total heat recovery devices can recover both sensible heat and latent heat, and common ones include plate-fin heat exchangers, rotary heat exchangers and heat pump heat exchangers.

[0005] 1. Sensible exhaust heat recovery unit

[0006] There are two types of sensible heat recovery units for exhaust air: plate type sensible heat recovery unit and heat pipe type sensible heat recovery unit. They recover waste heat by temperature difference sensible heat exchange and are reliable and safe in operation. However, they can only recover part of the sensible heat energy of the exhaust air and have limited heat recovery efficiency.

[0007] 2. Full heat exhaust heat recovery unit

[0008] (1) The total heat recovery efficiency of the chemical solution absorption type fresh air unit is high, which can reach more than 60%. The total heat recovery effect is stable and will not weaken with the extension of the use time. When the solution is used for heat exchange, it can remove most of the microorganisms, bacteria and inhalable particles in the air, and can effectively purify the air. The built-in solution filter can effectively ensure the cleanliness of the solution. During the heat exchange, the channels between the exhaust air and the fresh air are completely independent, solving the problem of cross contamination. The equipment requires a large net height space for installation and a high initial investment.

[0009] (2) The rotary full heat recovery unit has a large equipment volume, occupies a large building area and has a large net height. The pressure resistance is large, and a transmission device is required. It consumes some power during operation, has leakage, and cross contamination cannot be completely avoided during actual operation.

[0010] (3) The micropores on the surface of the specially treated filter paper of the wing-type full heat recovery unit with high-strength filter paper are blocked with special heat-generating polymer materials to prevent direct air flow. The wet transfer of latent heat exchange in the heat exchanger is completed by the capillary action of the paper fibers. When the outdoor temperature is below 0℃, ice blockage will occur.

[0011] (4) Heat pump type full heat recovery unit. The working principle of the heat pump is to transfer heat from the low-temperature heat source to the high-temperature heat source by absorbing heat from the evaporator and releasing heat from the condenser. That is, it can transfer the energy in the exhaust air to the fresh air. In summer conditions, the coil on the fresh air side is the evaporator, and the system extracts heat from the fresh air. The coil on the exhaust side is the condenser, which fully utilizes the coldness of the exhaust air and achieves the effect of cooling the fresh air. In winter conditions, the coil on the exhaust side is the evaporator, and the coil on the fresh air side is the condenser. The system absorbs heat from the exhaust side and achieves the purpose of heating the fresh air. When the coldness of the exhaust air and the fresh air in the system is unbalanced, an auxiliary cold and heat source can be set to supplement the cooling or heating of the fresh air.

[0012] Therefore, it is necessary to propose a dual-circulation exhaust heat recovery air-conditioning system under normal and emergency conditions to solve the above problems. Summary of the invention

[0013] In view of the deficiencies in the above-mentioned prior art, the object of the present invention is to provide a dual-circulation exhaust heat recovery air-conditioning system under combined normal and emergency conditions to solve the above-mentioned problems.

[0014] A dual-circulation exhaust heat recovery air conditioning system under normal and emergency combined working conditions, comprising a first compressor, a first four-way valve, a fresh air heat exchanger, a first throttle valve, an exhaust air heat exchanger, a second compressor, a second four-way valve, an indoor heat exchanger, a second throttle valve, an outdoor heat exchanger, a first control valve and a second control valve, wherein a first pipeline led out of a first exhaust port of the first compressor is connected to a port a of the first four-way valve; a port d of the first four-way valve is connected to one end of the fresh air heat exchanger via a second pipeline; a third pipeline led out of the other end of the fresh air heat exchanger is connected to one end of the first throttle valve; and the other end of the first throttle valve The fourth pipe led out is connected to one end of the exhaust heat exchanger; the fifth pipe led out from the other end of the exhaust heat exchanger is connected to the b port of the first four-way valve; the c port of the first four-way valve is connected to the first suction port of the first compressor via the sixth pipe; the seventh pipe led out from the second exhaust port of the second compressor is connected to the e port of the second four-way valve; the h port of the second four-way valve is connected to one end of the indoor heat exchanger via the eighth pipe; the ninth pipe led out from the other end of the indoor heat exchanger is connected to one end of the second throttle valve; the tenth pipe led out from the other end of the second throttle valve is connected to one end of the outdoor heat exchanger.

[0015] Preferably, an eleventh pipeline led out from the other end of the outdoor heat exchanger is connected to the f port of the second four-way valve; and the g port of the second four-way valve is connected to the suction port of the second compressor via a twelfth pipeline.

[0016] Preferably, the thirteenth pipeline branched from the fifth pipeline is connected to one end of the first control valve, and the other end of the first control valve is connected to the eleventh pipeline.

[0017] Preferably, the fourteenth pipeline branched from the third pipeline is connected to one end of the second control valve, and the other end of the second control valve is connected to the ninth pipeline.

[0018] Preferably, when the fresh air heat exchanger and the indoor heat exchanger are evaporators, the exhaust air heat exchanger and the outdoor heat exchanger are condensers.

[0019] Preferably, when the fresh air heat exchanger and the indoor heat exchanger are condensers, the exhaust air heat exchanger and the outdoor heat exchanger are evaporators.

[0020] Preferably, the first throttle valve and the second throttle valve are both solenoid valves or capillaries.

[0021] Preferably, the first control valve is arranged on the thirteenth pipeline, and the second control valve is arranged on the fourteenth pipeline.

[0022] Preferably, the first control valve and the second control valve are both normally open solenoid valves.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. In summer, the present invention can recover the cold in the exhaust air to remove heat and dehumidify the fresh air and the indoor air. In winter, the present invention can recover the heat in the exhaust air to heat the exhaust air and the indoor air, thereby realizing sensible heat and latent heat recovery. This solves the problem that the heat exchange effect of conventional heat recovery devices depends on the temperature difference and moisture content difference between the supply and exhaust air flows, and is greatly affected by the outdoor temperature and humidity.

[0025] 2. The present invention solves the problems that the conventional exhaust heat recovery system cannot guarantee the supply air temperature under special climatic conditions (extremely cold or hot), and part of the energy in the exhaust of the conventional exhaust heat recovery system is wasted. It realizes the use of the sensible heat and latent heat of the indoor exhaust air to heat the fresh air and defrost the outdoor unit at the same time, avoiding the defrosting model of conventional air conditioners such as electric heating and indoor heat absorption.

[0026] 3. The exhaust air full heat recovery air conditioning system of the present invention has a heat (cold) recovery amount that is fully adjustable in the range of 0 to 100%. It can achieve maximum utilization of fresh air for indoor air conditioning in both winter and summer working conditions, and greatly reduce the energy consumption of the air conditioning system in both normal and epidemic conditions in hospitals. By combining the air conditioning system with the wind system, it is possible to achieve full heat recovery of the exhaust air after centralized treatment of the fresh air and exhaust air, further ensuring the reliability of hygiene and heat recovery. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a principle structure diagram of the exhaust full heat recovery heat pump air conditioning system of the present invention;

[0028] Figure 2 is a structural diagram of the connection between the first compressor and the first four-way valve of the present invention;

[0029] Figure 3 is a structural diagram of the connection between the second compressor and the second four-way valve of the present invention;

[0030] Figure 4 It is a connection structure diagram of the exhaust heat exchanger, the first control valve, the indoor heat exchanger and the second control valve of the present invention.

[0031] Reference numerals in the figure: 1, first compressor; 101, first exhaust port; 102, first air intake port; 2, first four-way valve; 3, fresh air heat exchanger; 4, first throttle valve; 5, exhaust air heat exchanger; 6, second compressor; 601, second exhaust port; 602, second air intake port; 7, second four-way valve; 8, indoor heat exchanger; 9, second throttle valve; 10, outdoor heat exchanger; 11, first control valve; 12, second control valve;

[0032] L1, the first pipeline; L2, the second pipeline; L3, the third pipeline; L4, the fourth pipeline; L5, the fifth pipeline; L6, the sixth pipeline; L7, the seventh pipeline; L8, the eighth pipeline; L9, the ninth pipeline; L10, the tenth pipeline; L11, the eleventh pipeline; L12, the twelfth pipeline; L13, the thirteenth pipeline; L14, the fourteenth pipeline. DETAILED DESCRIPTION

[0033] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0034] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and the like are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", and the like may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0035] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0036] The embodiments of the present invention are described in detail below with reference to the accompanying drawings, but the present invention can be implemented in many different ways as defined and covered by the claims.

[0037] like Figure 1 Combined with Figures 2 to 4As shown, a dual-circulation exhaust heat recovery air conditioning system under normal and emergency combined working conditions includes a first compressor 1, a first four-way valve 2, a fresh air heat exchanger 3, a first throttle valve 4, an exhaust air heat exchanger 5, a second compressor 6, a second four-way valve 7, an indoor heat exchanger 8, a second throttle valve 9, an outdoor heat exchanger 10, a first control valve 11 and a second control valve 12, wherein a first pipeline L1 led out from a first exhaust port 101 of the first compressor 1 is connected to a port a of the first four-way valve 2; a port d of the first four-way valve 2 is connected to one end of the fresh air heat exchanger 3 via a second pipeline L2; a third pipeline L3 led out from the other end of the fresh air heat exchanger 3 is connected to one end of the first throttle valve 4; and a third pipeline L4 led out from the other end of the fresh air heat exchanger 3 is connected to one end of the first throttle valve 4; and a third pipeline L5 led out from the other end of the fresh air heat exchanger 3 is connected to one end of the first throttle valve 4. The fourth pipeline L4 is connected to one end of the exhaust heat exchanger 5; the fifth pipeline L5 led out from the other end of the exhaust heat exchanger 5 is connected to the b port of the first four-way valve 2; the c port of the first four-way valve 2 is connected to the first suction port 102 of the first compressor 1 via the sixth pipeline L6; the seventh pipeline L7 led out from the second exhaust port 601 of the second compressor 6 is connected to the e port of the second four-way valve 7; the h port of the second four-way valve 7 is connected to one end of the indoor heat exchanger 8 via the eighth pipeline L8; the ninth pipeline L9 led out from the other end of the indoor heat exchanger 8 is connected to one end of the second throttle valve 9; the tenth pipeline L10 led out from the other end of the second throttle valve 9 is connected to one end of the outdoor heat exchanger 10.

[0038] Furthermore, the eleventh pipeline L11 led out from the other end of the outdoor heat exchanger 10 is connected to the f port of the second four-way valve 7; the g port of the second four-way valve 7 is connected to the second suction port 602 of the second compressor 6 via the twelfth pipeline L12.

[0039] Furthermore, after the thirteenth pipeline L13 branched from the fifth pipeline L5 is connected to one end of the first control valve 11, the other end of the first control valve 11 is connected to the eleventh pipeline L11.

[0040] Furthermore, after the fourteenth pipeline L14 branched from the third pipeline L3 is connected to one end of the second control valve 12, the other end of the second control valve 12 is connected to the ninth pipeline L9.

[0041] Furthermore, when the fresh air heat exchanger 3 and the indoor heat exchanger 8 are evaporators, the exhaust air heat exchanger 5 and the outdoor heat exchanger 10 are condensers.

[0042] Furthermore, when the fresh air heat exchanger 3 and the indoor heat exchanger 8 are condensers, the exhaust air heat exchanger 5 and the outdoor heat exchanger 10 are evaporators.

[0043] Furthermore, the first throttle valve 4 and the second throttle valve 9 are both solenoid valves or capillaries.

[0044] Furthermore, the first control valve 11 is disposed on the thirteenth pipeline L13, and the second control valve 12 is disposed on the fourteenth pipeline L14.

[0045] Furthermore, the first control valve 11 and the second control valve 12 are both normally open solenoid valves.

[0046] Compared with the prior art, the present invention has the following beneficial effects:

[0047] 1. In summer, the present invention can recover the cold in the exhaust air to remove heat and dehumidify the fresh air and the indoor air. In winter, the present invention can recover the heat in the exhaust air to heat the exhaust air and the indoor air, thereby realizing sensible heat and latent heat recovery. This solves the problem that the heat exchange effect of conventional heat recovery devices depends on the temperature difference and moisture content difference between the supply and exhaust air flows, and is greatly affected by the outdoor temperature and humidity.

[0048] 2. The present invention solves the problems that the conventional exhaust heat recovery system cannot guarantee the supply air temperature under special climatic conditions (extremely cold or hot), and part of the energy in the exhaust of the conventional exhaust heat recovery system is wasted. It realizes the use of the sensible heat and latent heat of the indoor exhaust air to heat the fresh air and defrost the outdoor unit at the same time, avoiding the defrosting model of conventional air conditioners such as electric heating and indoor heat absorption.

[0049] 3. The exhaust air full heat recovery air conditioning system of the present invention has a heat (cold) recovery amount that is fully adjustable in the range of 0 to 100%. It can achieve maximum utilization of fresh air for indoor air conditioning in both winter and summer working conditions, and greatly reduce the energy consumption of the air conditioning system in both normal and epidemic conditions in hospitals. By combining the air conditioning system with the wind system, it is possible to achieve full heat recovery of the exhaust air after centralized treatment of the fresh air and exhaust air, further ensuring the reliability of hygiene and heat recovery.

[0050] Example 1

[0051] Under summer conditions, a dual-circulation exhaust heat recovery air-conditioning system under combined normal and emergency conditions for a hospital of the present invention is used as a summer refrigeration cycle to realize only exhaust cooling recovery conditions: the second compressor 6, the indoor heat exchanger 8, the outdoor heat exchanger 10 and the second throttle valve 9 are closed, and the exhaust gas of the first compressor 1 flows through the a end of the first four-way valve 2 and the b end of the first four-way valve 2 to the exhaust heat exchanger 5 for condensation, and the liquid working medium evaporates and absorbs heat in the fresh air heat exchanger 3 after throttling by the first throttle valve 4, and the gaseous working medium flows through the d end of the first four-way valve 2 and the c end of the first four-way valve 2 and then returns to the first compressor 1.

[0052] Example 2

[0053] Under summer conditions, a dual-circulation exhaust heat recovery air-conditioning system for hospital combined normal and emergency conditions of the present invention serves as a summer refrigeration cycle to achieve indoor refrigeration only and no exhaust cooling recovery: the first compressor 1, the fresh air heat exchanger 3, the exhaust air heat exchanger 5 and the first throttle valve 4 are closed, and the exhaust gas of the second compressor 6 flows through the e end of the second four-way valve 7 and the f end of the second four-way valve 7 to the outdoor heat exchanger 10 for condensation, and the liquid working medium evaporates and absorbs heat in the indoor heat exchanger 8 after throttling by the second throttle valve 9, and the gaseous working medium flows through the h end of the second four-way valve 7 and the g end of the second four-way valve 7 and then returns to the second compressor 6.

[0054] Example 3

[0055] Under summer conditions, a dual-cycle exhaust heat recovery air conditioning system under hospital emergency and normal conditions of the present invention is used as a summer refrigeration cycle to realize indoor refrigeration and exhaust cooling capacity recovery conditions at the same time: the solenoid valve 11 is opened and the solenoid valve 12 is closed, and the exhaust gas of the first compressor 1 flows through the a end of the first four-way valve 2 and the b end of the first four-way valve 2, and is mixed with the gaseous working medium of the second compressor 6 after the exhaust gas flows through the e end of the second four-way valve 7 and the f end of the second four-way valve 7, and is condensed in the outdoor heat exchanger 10, and the liquid working medium is throttled by the second throttle valve 9 and evaporates and absorbs heat in the indoor heat exchanger 8, and the gaseous working medium flows through the h end of the second four-way valve 7 and the g end of the second four-way valve 7 and then returns to the second compressor 6, and the other way is condensed in the exhaust heat exchanger 5, and the liquid working medium is throttled by the first throttle valve 4 and evaporates and absorbs heat in the fresh air heat exchanger 3, and the gaseous working medium flows through the d end of the first four-way valve 2 and the c end of the first four-way valve 2 and then returns to the first compressor 1.

[0056] Example 4

[0057] Under summer conditions, a dual-circulation exhaust heat recovery air-conditioning system under combined normal and emergency conditions of a hospital of the present invention is used as a summer refrigeration cycle to simultaneously recover exhaust cooling and outdoor heat, and only uses fresh air refrigeration conditions: the second compressor 6 and the indoor heat exchanger 8 are closed, the solenoid valve 11 and the solenoid valve 12 are opened, and the exhaust gas of the first compressor 1 flows through the a end of the first four-way valve 2 and the b end of the first four-way valve 2. The liquid working medium condensed in the exhaust heat exchanger 5 is throttled by the first throttle valve 4 and mixed with the liquid working medium condensed in the outdoor heat exchanger 10 through the other path after being throttled by the second throttle valve 9, evaporates and absorbs heat in the fresh air heat exchanger 3, and the gaseous working medium flows through the d end of the first four-way valve 2 and the c end of the first four-way valve 2 and then returns to the first compressor 1.

[0058] Example 5

[0059] Under summer conditions, a dual-circulation exhaust heat recovery air-conditioning system under combined normal and emergency conditions for a hospital of the present invention is used as a summer refrigeration cycle to simultaneously recover exhaust cooling and outdoor exhaust heat, and only operates under indoor refrigeration conditions: the first compressor 1 and the fresh air heat exchanger 2 are closed, the solenoid valves 11 and 12 are opened, and the exhaust gas of the second compressor 6 flows through the e end and the f end of the second four-way valve 7, and the liquid working medium condensed in the exhaust heat exchanger 5 is throttled by the first throttle valve 4 and mixed with the liquid working medium condensed in the outdoor heat exchanger 10 through the other path and throttled by the second throttle valve 9, and evaporates and absorbs heat in the indoor heat exchanger 8, and the gaseous working medium flows through the h end of the second four-way valve 7 and the g end of the first four-way valve 2 and then returns to the second compressor 6.

[0060] Example 6

[0061] Under winter conditions, a dual-circulation exhaust heat recovery air-conditioning system for hospital combined normal and emergency conditions of the present invention is used as a winter heating cycle to realize only exhaust heat recovery conditions: the second compressor 6, indoor heat exchanger 8, outdoor heat exchanger 10 and second throttle valve 9 are closed, and the exhaust gas of the first compressor 1 flows through the a end of the first four-way valve 2 and the d end of the first four-way valve 2 to the fresh air heat exchanger 3 for condensation, and the liquid working medium evaporates and absorbs heat in the exhaust heat exchanger 5 after throttling by the first throttle valve 4, and the gaseous working medium flows through the b end of the first four-way valve 2 and the c end of the first four-way valve 2 and then returns to the first compressor 1.

[0062] Example 7

[0063] Under winter conditions, a dual-circulation exhaust heat recovery air-conditioning system for hospital combined normal and emergency conditions of the present invention serves as a winter heating cycle to achieve indoor heating only and no exhaust heat recovery conditions: the first compressor 1, the fresh air heat exchanger 3, the exhaust air heat exchanger 5 and the first throttle valve 4 are closed, and the exhaust gas of the second compressor 6 flows through the e end of the second four-way valve 7 and the h end of the second four-way valve 7 to the indoor heat exchanger 8 for condensation, and the liquid working medium is throttled by the second throttle valve 9 and evaporates and absorbs heat in the outdoor heat exchanger 10, and the gaseous working medium flows through the f end of the second four-way valve 7 and the g end of the second four-way valve 7 and then returns to the second compressor 6.

[0064] Example 8

[0065] Under winter conditions, a dual-circulation exhaust heat recovery air conditioning system under combined normal and emergency conditions of a hospital of the present invention serves as a winter heating cycle to realize indoor heating and exhaust heat recovery conditions at the same time: the solenoid valve 11 is closed and the solenoid valve 12 is opened, and the exhaust gas of the first compressor 1 flows through the a end of the first four-way valve 2 and the d end of the first four-way valve 2 to the fresh air heat exchanger 3 for condensation, and then is mixed with the exhaust gas of the second compressor 6 through the e end of the second four-way valve 7 and the h end of the second four-way valve 7 to the indoor heat exchanger 8 for condensation. One path is throttled by the second throttle valve 9 and then evaporates and absorbs heat in the outdoor heat exchanger 10, and the gaseous working medium flows through the f end of the second four-way valve 7 and the g end of the second four-way valve 7 and then returns to the second compressor 6, and the other path is throttled by the first throttle valve 4 and then evaporates and absorbs heat in the exhaust heat exchanger 5, and the gaseous working medium flows through the b end of the first four-way valve 2 and the c end of the first four-way valve 2 and then returns to the first compressor 1.

[0066] Example 9

[0067] Under winter conditions, a dual-circulation exhaust heat recovery air-conditioning system under combined normal and emergency conditions of a hospital of the present invention is implemented as a winter heating cycle by only recovering exhaust heat, while performing outdoor heating and fresh air heating conditions: the second compressor 6 and the indoor heat exchanger 8 are closed, the solenoid valve 11 and the solenoid valve 12 are opened, and the exhaust gas of the first compressor 1 flows through the a end of the first four-way valve 2 and the d end of the first four-way valve 2 to the liquid working medium condensed in the fresh air heat exchanger 3. One path is throttled by the first throttle valve 4 and then evaporates and absorbs heat in the exhaust heat exchanger 5, and is mixed with the other path of the gaseous working medium that is throttled by the second throttle valve 9 and then evaporates and absorbs heat in the outdoor heat exchanger 10. The mixed gaseous working medium flows through the b end of the first four-way valve 2 and the c end of the first four-way valve 2 and then returns to the first compressor 1.

[0068] Example 10

[0069] Under winter conditions, a dual-circulation exhaust heat recovery air-conditioning system under combined normal and emergency conditions of a hospital of the present invention is used as a winter heating cycle to simultaneously recover exhaust heat and take heat from the outdoors, with only indoor heating conditions: the first compressor 1 and the fresh air heat exchanger 2 are closed, the solenoid valves 11 and 12 are opened, and the exhaust gas of the second compressor 6 flows through the e end and the h end of the second four-way valve 7 to the indoor heat exchanger 5 for condensation. The liquid working medium in one path is throttled by the first throttle valve 4 to the exhaust heat exchanger 5 for evaporation and heat absorption, and then mixed with the liquid working medium in the other path which is throttled by the second throttle valve 9 to the outdoor heat exchanger 10 for evaporation and heat absorption. The mixed gaseous working medium flows through the f end of the second four-way valve 7 and the g end of the first four-way valve 2 and then returns to the second compressor 6.

[0070] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A dual-circulation exhaust heat recovery air conditioning system under normal and emergency conditions, characterized in that: The invention comprises a first compressor (1), a first four-way valve (2), a fresh air heat exchanger (3), a first throttle valve (4), an exhaust air heat exchanger (5), a second compressor (6), a second four-way valve (7), an indoor heat exchanger (8), a second throttle valve (9), an outdoor heat exchanger (10), a first control valve (11) and a second control valve (12), wherein a first pipeline (L1) led out from a first exhaust port (101) of the first compressor (1) is connected to a port a of the first four-way valve (2); a port d of the first four-way valve (2) is connected to one end of the fresh air heat exchanger (3) via a second pipeline (L2); a third pipeline (L3) led out from the other end of the fresh air heat exchanger (3) is connected to one end of the first throttle valve (4); a fourth pipeline (L4) led out from the other end of the first throttle valve (4) is connected to a connected to one end of the exhaust heat exchanger (5); a fifth pipeline (L5) led out from the other end of the exhaust heat exchanger (5) is connected to the b port of the first four-way valve (2); the c port of the first four-way valve (2) is connected to the first air intake port (102) of the first compressor (1) via the sixth pipeline (L6); a seventh pipeline (L7) led out from the second exhaust port (601) of the second compressor (6) is connected to the e port of the second four-way valve (7); the h port of the second four-way valve (7) is connected to one end of the indoor heat exchanger (8) via the eighth pipeline (L8); a ninth pipeline (L9) led out from the other end of the indoor heat exchanger (8) is connected to one end of the second throttle valve (9); and a tenth pipeline (L10) led out from the other end of the second throttle valve (9) is connected to one end of the outdoor heat exchanger (10).

2. A dual-circulation exhaust heat recovery air conditioning system under normal and emergency conditions as claimed in claim 1, characterized in that: The eleventh pipeline (L11) leading out from the other end of the outdoor heat exchanger (10) is connected to the f port of the second four-way valve (7); the g port of the second four-way valve (7) is connected to the second suction port (602) of the second compressor (6) via the twelfth pipeline (L12).

3. A dual-circulation exhaust heat recovery air conditioning system under normal and emergency conditions as claimed in claim 1, characterized in that: The thirteenth pipeline (L13) branched from the fifth pipeline (L5) is connected to one end of the first control valve (11), and the other end of the first control valve (11) is connected to the eleventh pipeline (L11).

4. A dual-circulation exhaust heat recovery air conditioning system under normal and emergency conditions as claimed in claim 3, characterized in that: The fourteenth pipeline (L14) branched from the third pipeline (L3) is connected to one end of the second control valve (12), and the other end of the second control valve (12) is connected to the ninth pipeline (L9).

5. A dual-circulation exhaust heat recovery air conditioning system under normal and emergency conditions as claimed in claim 1, characterized in that: When the fresh air heat exchanger (3) and the indoor heat exchanger (8) are evaporators, the exhaust air heat exchanger (5) and the outdoor heat exchanger (10) are condensers.

6. A dual-circulation exhaust heat recovery air conditioning system under normal and emergency conditions as claimed in claim 1, characterized in that: When the fresh air heat exchanger (3) and the indoor heat exchanger (8) are condensers, the exhaust air heat exchanger (5) and the outdoor heat exchanger (10) are evaporators.

7. A dual-circulation exhaust heat recovery air conditioning system under normal and emergency conditions as claimed in claim 1, characterized in that: The first throttle valve (4) and the second throttle valve (9) are both solenoid valves or capillaries.

8. A dual-circulation exhaust heat recovery air conditioning system under normal and emergency conditions as claimed in claim 4, characterized in that: The first control valve (11) is arranged on the thirteenth pipeline (L13), and the second control valve (12) is arranged on the fourteenth pipeline (L14).

9. A dual-circulation exhaust heat recovery air conditioning system under normal and emergency conditions as claimed in claim 8, characterized in that: The first control valve (11) and the second control valve (12) are both normally open solenoid valves.

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