Disclosure of Invention
First, the technical problem to be solved
The embodiment of the invention provides a composite energy air treatment unit, which aims to solve the technical problems that the reheating process of the air treatment unit in the prior art is high in energy consumption, difficult to operate efficiently all the year round and more in heat transfer links.
(II) technical scheme
In order to solve the technical problems, the embodiment of the invention provides a composite energy air treatment unit, which comprises an air conditioning box body, a ground source heat exchanger, a compressor, a circulating pump and a composite heat exchanger, wherein the ground source heat exchanger, the compressor, the circulating pump and the composite heat exchanger are arranged outside the air conditioning box body; the hollow cavity in the air conditioning box body forms a gas channel, one end of the gas channel is an air inlet, and the other end is an air outlet; the first heat exchanger, the second heat exchanger, the third heat exchanger and the first fan are sequentially arranged in the gas channel according to the air flowing direction; one end of the circulating pump is connected with the ground source heat exchanger through a pipeline, and the other end of the circulating pump is connected with the first heat exchanger and the composite heat exchanger through a pipeline to form a first secondary refrigerant loop; one end of the compressor is connected with the second heat exchanger through a pipeline, and the other end of the compressor is connected with the third heat exchanger and the composite heat exchanger through pipelines to form a first refrigerant loop.
The first secondary refrigerant loop comprises a first secondary refrigerant circulation branch and a second secondary refrigerant circulation branch; the first secondary refrigerant circulating branch is formed by connecting a first heat exchanger, a ground source heat exchanger and a circulating pump in series; the second secondary refrigerant circulating branch is formed by serially connecting a ground source heat exchanger, a circulating pump and a first medium channel of the compound heat exchanger.
Wherein the first refrigerant circuit includes a first refrigerant circulation branch and a second refrigerant circulation branch; the first refrigerant circulation branch is formed by connecting a second heat exchanger, a second medium channel of the compound heat exchanger and a compressor in series; the second refrigerant circulation branch is formed by connecting a second heat exchanger, a third heat exchanger and a compressor in series.
The invention also provides a composite energy air treatment unit which comprises an air conditioning box body, and further comprises a ground source heat exchanger, a compressor, a circulating pump and a composite heat exchanger which are arranged outside the air conditioning box body; the hollow cavity in the air conditioning box body forms a gas channel, one end of the gas channel is an air inlet, and the other end is an air outlet; the first heat exchanger, the second heat exchanger, the third heat exchanger and the first fan are sequentially arranged in the gas channel according to the air flowing direction; one end of the circulating pump is connected with the ground source heat exchanger through a pipeline, and the other end of the circulating pump is connected with the first heat exchanger, the compound heat exchanger and the third heat exchanger through pipelines to form a second secondary refrigerant loop; the compressor is connected with the second heat exchanger and the compound heat exchanger through pipelines to form a second refrigerant loop.
The second secondary refrigerant loop comprises a third secondary refrigerant circulation branch, a fourth secondary refrigerant circulation branch and a fifth secondary refrigerant circulation branch; the third secondary refrigerant circulating branch is formed by connecting a first heat exchanger, a ground source heat exchanger and a circulating pump in series; the fourth secondary refrigerant circulating branch is formed by connecting a ground source heat exchanger, a circulating pump, a first medium channel of a compound heat exchanger and a third heat exchanger in series; the fifth secondary refrigerant circulating branch is formed by serially connecting a ground source heat exchanger, a circulating pump and a first medium channel of the compound heat exchanger.
The second refrigerant loop is formed by connecting a second heat exchanger, a second medium channel of the compound heat exchanger and a compressor in series.
The composite energy air treatment unit further comprises a humidifier arranged in the gas channel.
The composite energy air treatment unit further comprises a filter which is arranged in the air channel and close to the air inlet.
Wherein, the compound energy air treatment unit also comprises an air return port; the air return port is communicated with the gas channel and is positioned between the first heat exchanger and the second heat exchanger.
The composite energy air treatment unit further comprises a second fan arranged on the composite heat exchanger.
(III) beneficial effects
According to the composite energy air treatment unit provided by the embodiment of the invention, the third heat exchanger connected with the compressor is used for reheating air, so that the condensation waste heat is directly utilized, and the extra reheat energy consumption required in the traditional primary return air treatment process is greatly reduced. In addition, the secondary refrigerant is adopted to recover condensation heat, so that free reheating is realized, and the energy consumption in the reheating process can be reduced; the advantages of the soil source and the air source heat pump are combined, the heat exchange is carried out by adopting the composite heat exchanger, the composite system is simplified, and the device can efficiently treat air all year round under the condition that no independent heat exchanger is added; compared with the traditional air conditioning box which adopts cold water and hot water provided by a heat pump to treat air, the direct expansion system reduces the energy loss in the heat transfer link.
Detailed Description
The following describes in further detail the embodiments of the present invention with reference to the drawings and examples. The following examples are illustrative of the invention and are not intended to limit the scope of the invention.
In the description of the present invention, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.
As shown in fig. 1, the embodiment of the invention provides a composite energy air treatment unit, which comprises an air conditioning box body 1, and further comprises a ground source heat exchanger 12, a compressor 20, a circulating pump 11 and a composite heat exchanger 8 which are arranged outside the air conditioning box body 1; the hollow cavity in the air conditioning box body 1 forms a gas channel, one end of the gas channel is an air inlet 2, and the other end is an air outlet 7; the first heat exchanger 3, the second heat exchanger 4, the third heat exchanger 5 and the first fan 6 are sequentially arranged in the gas channel according to the air flowing direction; one end of the circulating pump 11 is connected with the ground source heat exchanger 12 through a pipeline, and the other end of the circulating pump is connected with the first heat exchanger 3 and the composite heat exchanger 8 through a pipeline to form a first secondary refrigerant loop; one end of the compressor 20 is connected with the second heat exchanger 4 through a pipeline, and the other end is connected with the third heat exchanger 5 and the composite heat exchanger 8 through pipelines to form a first refrigerant loop.
Specifically, for example, in hot summer, when the device is in a refrigerating working condition, air enters the air channel from the air inlet 2 and then exchanges heat with the secondary refrigerant in the first heat exchanger 3, so that the temperature is reduced, and the precooling function is realized; as the outdoor air and the return air are mixed and continue to flow forwards, heat exchange is carried out between the outdoor air and the refrigerant at the second heat exchanger 4, at the moment, the refrigerant entering the second heat exchanger 4 can carry out cooling and dehumidifying treatment on the air again, at the moment, the refrigerant in the second heat exchanger 4 absorbs heat, the refrigerant after absorbing heat is conveyed to the third heat exchanger 5 under the action of the compressor 20 and is used for reheating the air after cooling and dehumidifying, and the reheated air is sent into a room through the air outlet 7; the refrigerant flowing out of the third heat exchanger 5 is refluxed to the second heat exchanger 4 after heat release for cooling and dehumidifying the air, and the refrigerant is circulated and reciprocated; the refrigerant flowing out of the compressor 20 can also flow into the second medium channel 10 of the composite heat exchanger 8, be cooled by the secondary refrigerant or the outdoor air from the ground source heat exchanger 12, and then flow into the second heat exchanger 4 for performing cooling and dehumidifying treatment on the air in the air-conditioning box, and circulate. If the outdoor heat exchange medium is the secondary refrigerant, the secondary refrigerant returns to the ground source heat exchanger 12 again for circulating heat exchange under the delivery of the circulating pump 11; if the outdoor heat exchange medium is air, it exchanges heat with the refrigerant by the driving of the second fan 14.
According to the composite energy air treatment unit provided by the embodiment of the invention, the third heat exchanger 5 connected with the compressor 20 is used for reheating air, so that the condensation waste heat is fully utilized, and the extra reheating energy consumption required in the traditional primary return air treatment process is greatly reduced; the soil source and air source heat pump systems are combined, and the heat exchange is carried out by adopting the composite heat exchanger 8, so that the composite system is simplified, and the two heat pump operation modes can be flexibly switched under the condition that an independent heat exchanger is not added; compared with the traditional air conditioning box which adopts the secondary refrigerant provided by the heat pump unit to treat air, the direct expansion system reduces the energy loss in the heat transfer link.
Further, the first coolant circuit includes a first coolant circulation branch and a second coolant circulation branch; the first secondary refrigerant circulating branch is formed by connecting a first heat exchanger 3, a ground source heat exchanger 12 and a circulating pump 11 in series; the second secondary refrigerant circulating branch is formed by connecting a ground source heat exchanger 12, a circulating pump 11 and a first medium channel 9 of the compound heat exchanger 8 in series.
Specifically, for example, the pipe connected to the outlet of the circulation pump 11 may be divided into two branch pipes, one of which is provided with the second valve 16 and the other end of which is connected to the inlet of the first heat exchanger 3; a first valve 15 is arranged on the other branch, and the other end of the branch is connected to one end of the first medium passage 9. The secondary refrigerant output by the circulating pump 11 in the ground source heat exchanger 12 can be divided into two streams, and one stream is conveyed to the first heat exchanger 3 for fresh air pretreatment; the other is sent to the complex heat exchanger 8 for heat exchange with the refrigerant. Wherein the operation mode of the combined energy air treatment unit can be controlled by controlling the opening or closing of the first valve 15 or the second valve 16.
Further, the first refrigerant circuit includes a first refrigerant circulation branch and a second refrigerant circulation branch; the first refrigerant circulation branch is formed by connecting a second heat exchanger 4, a second medium channel 10 of the compound heat exchanger 8 and a compressor 20 in series; the second refrigerant cycle branch is formed by connecting the second heat exchanger 4, the third heat exchanger 5 and the compressor 20 in series.
Specifically, for example, a four-way valve 21 may be disposed on a pipeline connected to the outlet of the compressor 20, and one end of the bottommost end of the four-way valve 21 is denoted as a first end, and then the second end, the third end and the fourth end of the four-way valve 21 are respectively arranged in a clockwise direction; wherein the second end of the four-way valve 21 is connected with the outlet of the second heat exchanger 4 through a pipeline; the third end of the four-way valve 21 is connected with the inlet of the compressor 20 through a pipeline; wherein, the pipeline connected with the fourth end of the four-way valve 21 is divided into two branch pipes, one branch pipe is connected with the inlet of the third heat exchanger 5, and the other branch pipe is connected with one end of the second medium channel 10; the other end of the second medium channel 10 is connected with the inlet of the second heat exchanger 4 through a pipeline; the outlet of the third heat exchanger 5 may merge via a line between the line and the second medium channel 10 and the inlet of the second heat exchanger 4. Here, the inlets and outlets of the compressor 20, the second heat exchanger 4, and the third heat exchanger 5 are not absolute, but are distinguished for the sake of clarity in explaining the connection relationship between the respective portions, and in fact, the inlet may be an outlet, and the outlet corresponds to the inlet, depending on the flow direction of the refrigerant or the secondary refrigerant. A first expansion valve 17 may be provided on a line connected to the inlet of the second heat exchanger 4, a second expansion valve 18 may be provided on a branch line connected to the other end of the second medium passage 10, and a third expansion valve 19 may be provided on a branch line connected to the third heat exchanger 5; the first expansion valve 17, the second expansion valve 18, and the third expansion valve 19 may be any device capable of generating a throttling effect, such as an electronic expansion valve, a thermal expansion valve, a capillary tube, a throttle plate, and an expander.
As shown in fig. 2, the invention also provides a composite energy air treatment unit, which comprises an air conditioning box body 1, and further comprises a ground source heat exchanger 12, a compressor 20, a circulating pump 11 and a composite heat exchanger 8 which are arranged outside the air conditioning box body 1; the hollow cavity in the air conditioning box body 1 forms a gas channel, one end of the gas channel is an air inlet 2, and the other end is an air outlet 7; the first heat exchanger 3, the second heat exchanger 4, the third heat exchanger 5 and the first fan 6 are sequentially arranged in the gas channel according to the air flowing direction; one end of the circulating pump 11 is connected with the ground source heat exchanger 12 through a pipeline, and the other end of the circulating pump is connected with the first heat exchanger 3, the compound heat exchanger 8 and the third heat exchanger 5 through pipelines to form a second secondary refrigerant loop; the compressor 20 is connected to the second heat exchanger 4 and the composite heat exchanger 8 through a pipe line to form a second refrigerant circuit.
Specifically, for example, in hot summer, when the device is in a refrigerating condition, air enters the air channel from the air inlet 2 and then contacts the first heat exchanger 3, and the first heat exchanger 3 cools the air flowing through the air channel, namely precooling treatment; as the outdoor air and the return air are mixed and continue to flow forwards, the outdoor air contacts the second heat exchanger 4, at the moment, the refrigerant in the second heat exchanger 4 can perform cooling and dehumidifying treatment on the air again, at the moment, the refrigerant in the second heat exchanger 4 absorbs heat, and the refrigerant after absorbing heat is conveyed into the second medium channel 10 under the action of the compressor 20, and heat exchange is performed in the composite heat exchanger 8; the refrigerant in the composite heat exchanger 8 can be cooled by the secondary refrigerant or outdoor air from the ground source heat exchanger 12, and the cooled refrigerant flows into the second heat exchanger 4 again for cooling and dehumidifying the air, and is circulated and reciprocated; for the secondary refrigerant in the first medium channel 9, the temperature rises after heat exchange with the refrigerant in the second medium channel 10, therefore, if the outdoor heat exchange medium is the secondary refrigerant, the other end of the first medium channel 9 can be connected with the third heat exchanger 5, the air after temperature and humidity reduction is reheated by the warmed secondary refrigerant, and then the secondary refrigerant returns to the ground source heat exchanger 12 for circulating heat exchange; if the outdoor heat exchange medium is air, it exchanges heat with the refrigerant by the driving of the second fan 14.
According to the composite energy air treatment unit provided by the embodiment of the invention, the ground source heat exchanger 12 is connected with the third heat exchanger 5, and the secondary refrigerant is adopted to recover condensation heat, so that free reheating is realized, and the energy consumption in the reheating process can be reduced; the soil source and air source heat pump systems are combined, and the heat exchange is carried out by adopting the composite heat exchanger 8, so that the composite system is simplified, and the two heat pump operation modes can be flexibly switched under the condition that an independent heat exchanger is not added; compared with the traditional air conditioning box which adopts the secondary refrigerant provided by the heat pump unit to treat air, the direct expansion system reduces the energy loss in the heat transfer link.
Further, the second coolant loop includes a third coolant circulation branch, a fourth coolant circulation branch, and a fifth coolant circulation branch; the third secondary refrigerant circulating branch is formed by connecting a first heat exchanger 3, a ground source heat exchanger 12 and a circulating pump 11 in series; the fourth secondary refrigerant circulating branch is formed by serially connecting a ground source heat exchanger 12, a circulating pump 11, a first medium channel 9 of the compound heat exchanger 8 and a third heat exchanger 5; the fifth secondary refrigerant circulating branch is formed by serially connecting a ground source heat exchanger 12, a circulating pump 11 and a first medium channel of the compound heat exchanger 8.
Specifically, for example, the pipe connected to the outlet of the circulation pump 11 may be divided into two branch pipes, one of which is provided with the second valve 16 and the other end of which is connected to the inlet of the first heat exchanger 3; a first valve 15 is arranged on the other branch, and the other end of the branch is connected to one end of the first medium passage 9. The secondary refrigerant output by the circulating pump 11 in the ground source heat exchanger 12 can be divided into two streams, and one stream is conveyed to the first heat exchanger 3 for fresh air pretreatment; the other is sent to the complex heat exchanger 8 for heat exchange with the refrigerant. Wherein the operation mode of the combined energy air treatment unit can be controlled by controlling the opening or closing of the first valve 15 or the second valve 16. The coolant flowing out of the first medium passage 9 can be made to flow into the third heat exchanger 5 by providing a branch pipe, and then return to the ground source heat exchanger 12. For example, a third valve 24 can be provided in the line between the coolant outlet of the first medium channel 9 and the inlet of the third heat exchanger 5, and a fourth valve 25 can be provided in the line between the two nodes of the third heat exchanger 5 connected to the main pipe; when the fourth valve 25 is closed and the third valve 24 is opened, the coolant flowing out of the first medium channel 9 flows through the third heat exchanger 5 and returns to the ground source heat exchanger 12. In actual operation, the opening or closing of the third valve 24 and the fourth valve 25 can be controlled according to the requirement to adjust the operation mode of the composite energy air treatment unit.
Further, the second refrigerant circuit is constituted by connecting the second heat exchanger 4, the second medium passage 10 of the composite heat exchanger 8, and the compressor 20 in series.
Specifically, for example, the fourth end of the four-way valve 21 may be connected to one end of the second medium passage 10 through a pipe, the other end of the second medium passage 10 may be connected to the inlet of the second heat exchanger 4 through a pipe, and the outlet of the second heat exchanger 4 may be connected to the inlet of the compressor 20 through a pipe.
Further, the complex energy air treatment unit further includes a humidifier 13 provided in the air passage of the air conditioning case. Specifically, for example, the humidifier 13 may be a water sprayer or a device capable of realizing a humidifying function such as a steam spraying device. The humidifier 13 may be turned on as needed to humidify the air fed into the room.
Further, the composite energy air treatment unit further comprises a filter 23 arranged in the gas channel near the air inlet 2. Specifically, for example, the filter 23 may be any kind of purifying device. The filter 23 may be disposed between the air inlet 2 and the first heat exchanger 3, and may filter and purify the air flowing in from the air inlet 2 and then exchange heat with the first heat exchanger 3.
Further, the composite energy air treatment unit also comprises an air return opening 22; the return air inlet 22 is communicated with the gas channel and is positioned between the first heat exchanger 3 and the second heat exchanger 4. Specifically, for example, the indoor return air can enter the air channel through the return air inlet 22, be mixed with the air entering through the air inlet 2, and enter the room after passing through the second heat exchanger 4 and/or the third heat exchanger 5 for heat exchange; the arrangement is beneficial to saving energy consumption.
Further, the composite energy air treatment unit further comprises a second fan 14 arranged on the composite heat exchanger 8. The arrangement of the second fan 14 can play a role in forced convection, and is beneficial to realizing efficient heat exchange of air, refrigerant and secondary refrigerant at the position of the composite heat exchanger 8.
Several modes of operation of the air treatment unit are described below in connection with the present combination:
mode one, mid-season of cold supply: precooling, water cooling unit refrigeration and reheating
As shown in fig. 1, the circulation pump 11, the first valve 15, the second valve 16, the compressor 20, the first expansion valve 17, the second expansion valve 18, the third expansion valve 19, and the first fan 6 are all opened, and the second fan 14 and the humidifier 13 are closed. The secondary refrigerant is split through the outlet of the circulating pump 11: one path flows through the first valve 15, absorbs heat and heats up in the first medium channel 9; one path is subjected to heat exchange with air in the first heat exchanger 3 through the second valve 16 to raise the temperature. The secondary refrigerant after confluence passes through the ground source heat exchanger 12 to release heat and reduce temperature, and then returns to the inlet of the circulating pump 11. The refrigerant is split from the outlet of the compressor 20 through the four-way valve 21: one path enters the third heat exchanger 5 for air reheating and then flows through the third expansion valve 19; one path enters the second medium channel 10 of the compound heat exchanger 8 to exchange heat with the secondary refrigerant, and then flows through the second expansion valve 18. The converged refrigerant passes through the first expansion valve 17 to generate throttling effect, then enters the second heat exchanger 4 to absorb air heat, and then flows through the four-way valve 21 to return to the inlet of the compressor 20. Fresh air enters the air channel through the air inlet 2, exchanges heat with the secondary refrigerant at the first heat exchanger 3 after passing through the filter 23, is mixed with return air entering at the return air inlet 22 after precooling, exchanges heat with the refrigerant at the second heat exchanger 4, cools and dehumidifies, and then passes through the third heat exchanger 5 to achieve reheating, enters the first fan 6, enters the air pipe from the air outlet 7 and finally enters the room.
As shown in fig. 2: the circulation pump 11, the first valve 15, the second valve 16, the compressor 20, the first expansion valve 17, the first fan 6, the third valve 24 and the fourth valve 25 are all opened, and the second fan 14 and the humidifier 13 are closed. The coolant is split through the outlet of the circulation pump 11: one path flows through the first valve 15, absorbs heat in the first medium channel 9 and heats up, then part of secondary refrigerant flows through the fourth valve 25 from the left side of the first medium channel 9, and part of secondary refrigerant flows through the third valve 24 and flows through the third heat exchanger 5 to exchange heat with air and cool down; the other path is subjected to heat exchange with air in the first heat exchanger 3 through the second valve 16 to raise the temperature. The secondary refrigerant after confluence passes through the ground source heat exchanger 12 to release heat and reduce temperature, and then returns to the inlet of the circulating pump 11. The refrigerant enters the second medium channel 10 of the compound heat exchanger 8 from the outlet of the compressor 20 through the four-way valve 21 to exchange heat with the secondary refrigerant, then passes through the first expansion valve 17 to generate throttling effect, then enters the second heat exchanger 4 to absorb air heat, and then flows through the four-way valve 21 to return to the inlet of the compressor 20. Fresh air enters the air channel through the air inlet 2, exchanges heat with the secondary refrigerant at the first heat exchanger 3 after passing through the filter 23, is mixed with return air entering at the return air inlet 22 after realizing the precooling function, exchanges heat with the refrigerant at the second heat exchanger 4, and is reheated after cooling and dehumidifying by exchanging heat with the secondary refrigerant through the third heat exchanger 5, then enters the first fan 6, enters the air pipe from the air outlet 7 and finally enters the room.
Mode two, mid-heating season: preheating and heating by water source heat pump unit
As shown in fig. 1: the circulation pump 11, the first valve 15, the second valve 16, the compressor 20, the first expansion valve 17, the second expansion valve 18, the first fan 6 and the humidifier 13 are all opened, and the second fan 14 and the third expansion valve 19 are closed. The coolant is split through the outlet of the circulation pump 11: one path flows through the first valve 15, and releases heat and lowers temperature in the first medium channel 9; one path exchanges heat with air in the first heat exchanger 3 through the second valve 16 to cool down. The concentrated coolant is heated by the heat absorption of the ground source heat exchanger 12 and then returns to the inlet of the circulating pump 11. The refrigerant enters the second heat exchanger 4 from the outlet of the compressor 20 through the four-way valve 21, releases heat, passes through the first expansion valve 17, throttles at the second expansion valve 18, exchanges heat with the secondary refrigerant through the second medium channel 10 of the composite heat exchanger 8, and returns to the inlet of the compressor 20. Fresh air enters the air channel through the air inlet 2, exchanges heat with the secondary refrigerant at the first heat exchanger 3 after passing through the filter 23, is mixed with return air entering at the return air inlet 22 after being preheated, exchanges heat with the refrigerant at the second heat exchanger 4 for heating, and the heated air enters the first fan 6 after being humidified by the humidifier 13, enters the air pipe from the air outlet 7 and finally enters a room.
As shown in fig. 2: the third valve 24 is opened and the fourth valve 25 is closed, otherwise the same as in fig. 1, and further description thereof will be omitted.
Mode three, early and end of cold season: air cooling unit refrigeration
As shown in fig. 1 or 2, the compressor 20, the first expansion valve 17, the second expansion valve 18, the first fan 6, the third expansion valve 19, and the second fan 14 are all on, and the circulation pump 11, the first valve 15, the second valve 16, and the humidifier 13 are off. The refrigerant is split from the outlet of the compressor 20 through the four-way valve 21: one path enters the third heat exchanger 5 for air reheating and then flows through the third expansion valve 19; one path enters the second medium channel 10 of the compound heat exchanger 8 to exchange heat with the outdoor air, and then flows through the second expansion valve 18. The refrigerant after converging passes through the first expansion valve 17 to generate throttling effect, then enters the second heat exchanger 4 to absorb air heat, and then flows through the four-way valve 21 to return to the inlet of the compressor 20. Fresh air enters the air channel through the air inlet 2, is mixed with return air entering from the return air inlet 22 after passing through the filter 23, the mixed air exchanges heat with the refrigerant at the second heat exchanger 4, the dehumidified and cooled air is reheated through the third heat exchanger 5, and then enters the first fan 6, enters the air pipe from the air outlet 7 and finally enters the room.
Mode four, early and late heating season: air cooling unit heating
As shown in fig. 1 or 2, the compressor 20, the first expansion valve 17, the second expansion valve 18, the first fan 6, and the second fan 14 are all on, and the circulation pump 11, the first valve 15, the second valve 16, the humidifier 13, and the third expansion valve 19 are all off. The refrigerant enters the second heat exchanger 4 from the outlet of the compressor 20 through the four-way valve 21 to release heat, passes through the first expansion valve 17, throttles at the second expansion valve 18, passes through the second medium channel 10 of the compound heat exchanger 8 to exchange heat with outdoor air, and then flows through the four-way valve 21 to return to the inlet of the compressor 20. Fresh air enters the air channel through the air inlet 2, is mixed with return air entering from the return air inlet 22 after passing through the filter 23, and the mixed air exchanges heat with the refrigerant at the second heat exchanger 4 to raise temperature, and the air after temperature raising enters the air pipe from the air outlet 7 and finally enters the room through the first fan 6.
Mode five, the ground source supplements cold/heat
As shown in fig. 1 or 2, when the fresh air does not need to be treated with the refrigerant cycle in a transition season or the like, the cold/heat in the air can be used to supplement the cold/heat to the soil. At this time, the circulation pump 11, the first valve 15 and the second fan 14 are turned on, the compressor 20, the second valve 16, the first fan 6 and the humidifier 13 are turned off, and the system is operated in the "ground source cooling/heating" mode. At this time, the secondary refrigerant enters the first medium channel 9 through the first valve 15 from the outlet of the circulating pump 11 to exchange heat with air, then enters the ground source heat exchanger 12 from the first medium channel 9 to exchange heat with soil, balances the cold/heat of the soil, and returns to the inlet of the circulating pump 11.
Mode six, ground source temperature regulation
As shown in fig. 1 or 2, the air can be simply conditioned by only using the heat and cold of the ground source even when the fresh air is not required to be circulated with the refrigerant in a transition season or the like. At this time, the circulation pump 11, the second valve 16 and the first fan 6 are turned on, the compressor 20, the first valve 15 and the second fan 14 are turned off, and the system is operated in the ground source temperature adjustment mode. The secondary refrigerant enters the first heat exchanger 3 from the outlet of the circulating pump 11 through the second valve 16, exchanges heat with air, enters the ground source heat exchanger 12, exchanges heat with soil, and then returns to the inlet of the circulating pump 11. The fresh air is subjected to heat exchange with the secondary refrigerant at the first heat exchanger 3 after passing through the filter 23, and then is mixed with the return air, and flows out from the air outlet 7 under the drive of the first fan 6.
From the above embodiments, it can be seen that the composite energy air treatment unit provided by the invention has the following beneficial effects:
1. Compared with the traditional summer air treatment process of primary return air, the method greatly reduces the extra reheat energy consumption required by consumption, adopts the third heat exchanger as a direct expansion condenser in the refrigerant cycle for reheating, or adopts the third heat exchanger as a reheater for recovering the condensing heat of a unit in the secondary refrigerant cycle, thereby realizing free reheating. The system has good application prospect in areas with larger wet load and smaller cold load (such as Yangtze river basin in China).
2. Natural energy is fully utilized in each link of air treatment, and the energy consumption of air treatment is reduced. The problem that the heat unbalance of the soil is easily caused by long-term operation of the conventional air treatment unit based on the ground source heat pump unit is solved, the annual cold load is obviously larger than the heat load in the Yangtze river basin area, and the phenomenon of the heat unbalance of the soil is greatly reduced; the problem that the conventional air treatment unit based on the air source heat pump unit is low in winter and summer operation efficiency and easy to cause frosting of the outdoor heat exchanger when the air treatment unit is operated in high humidity and cold areas in winter is solved. Meanwhile, the heat exchange is carried out by adopting the composite heat exchanger, a composite system is simplified, and the device can be operated at high efficiency all year round under the condition that an independent heat exchanger is not added.
3. Compared with the traditional air conditioning box which adopts cold water and hot water provided by a heat pump unit to treat air, the direct expansion system reduces the energy loss in the heat transfer link.
In conclusion, the air source and the ground source are connected through the composite heat exchanger to serve as energy sources for fresh air treatment, and meanwhile, the multi-split air conditioner directly utilizes condensation heat by adopting one-split multi-split air conditioner, so that the air treatment method by fully utilizing natural energy sources is realized. The problems of the traditional air treatment unit based on the single source heat pump are avoided, and according to different energy grades, natural energy with proper temperature is used for treating air in each link, so that the device can operate efficiently all year round.
The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, alternatives, and improvements that fall within the spirit and scope of the invention.