CN108759138A

CN108759138A - The operation method and system of not exclusively cooling refrigeration system among second throttle

Info

Publication number: CN108759138A
Application number: CN201810800244.6A
Authority: CN
Inventors: 杨永安; 李瑞申
Original assignee: Tianjin University of Commerce
Current assignee: Tianjin University of Commerce
Priority date: 2018-07-20
Filing date: 2018-07-20
Publication date: 2018-11-06
Anticipated expiration: 2038-07-20
Also published as: CN108759138B

Abstract

The invention discloses the operation methods and system of not exclusively cooling refrigeration system among a kind of second throttle, it is desirable to provide a kind of method and system for using low-pressure stage compressor heat pump circulation to defrost for cryogenic vaporizer.There are medium temperature evaporator and cryogenic vaporizer, medium temperature evaporator to freeze for realizing medium temperature in each low-pressure stage unit, cryogenic vaporizer is for realizing cryogenic refrigeration or defrosting.When there is cryogenic vaporizer to need defrosting, pass through valve transfer, realize that the low-pressure stage compressor of defrosting function is converted into high pressure stage compressor operation, it realizes that the cryogenic compressor in the low-pressure stage unit of defrosting function is absorbed and presses through heat steam in the low-pressure stage compressor for realizing refrigerating function, condensation heating cryogenic vaporizer to be defrosted realizes defrosting after compression.The present invention uses low-pressure stage compressor heat pump circulation to defrost for cryogenic vaporizer, and temperature fluctuation is small, and defrosting efficiency is high, can provide the cold of refrigerator and guick freezing room.

Description

The operation method and system of not exclusively cooling refrigeration system among second throttle

Technical field

The present invention relates to refrigeration technology field, more specifically, it relates to a kind of to use heat pump with medium temperature evaporator The operation method and refrigeration system of not exclusively cooling refrigeration system among the second throttle of defrosting.

Background technology

In freezer, when heat exchanger cooling surface is covered by frost layer, if removing not in time, then frost accumulated will be such that compressor inhales Temperature degree reduces, and delivery temperature rises, and blocks air duct, reduces heat transfer area, and the flow resistance of air is dramatically increased, changed The thermal efficiency acutely reduces, and refrigerating plant runnability declines.The quality of defrosting effect be also the capacity of equipment for giving full play to freezer, Reduce overhaul cost, using electricity wisely and the key for ensureing food quality.

Mainly there is evaporator Defrost method in existing freezer：Electrical heating method, water drenching method, reverse cycle defrosting method etc..Wherein, The two kinds of defrosting defrostings of electrical heating method and water drenching method are all external heating frost layers, and frost is to melt outside in, so actually removing The heat ratio theoretical value of frost is much bigger, and this defrosting big energy-consuming, operating cost is higher, from safety and stability and energy saving upper consideration, It has been rarely employed now.Reverse cycle defrosting method origin of heat is in the wasted work of outdoor environment and compressor, by changing four-way commutation The connection type of valve temporarily changes the flow direction of the working medium of entire refrigeration system, and then changes the shift direction of heat, makes steaming Hair device is changed into condenser, reaches defrosting effect for evaporator heating, but refrigeration cycle stops in defrosting at this time, Suo Youzheng Sending out device cannot continue to freeze.Reverse cycle defrosting method defrosting efficiency is high, energy saving reliable.But this defrosting is only applicable to structure Simple single-stage compression refrigeration system, for the lower double-stage compressive refrigerating system of evaporating temperature, due to temperature of ice house compared with It is low, when inverse cycle being used to defrost for evaporator, if entire refrigeration system antikinesis, all evaporators of freezer all switch to Condenser, since the temperature difference between evaporator surface temperature and cold storehouse temperature is larger, defrosting time is longer, the temperature wave of freezer It is dynamic larger, food drying loss can be caused, economic loss is caused.Therefore, for make Two-stage Compression system keep high-efficiency operation, it is necessary to it is right Evaporator progress is orderly, efficiently defrosts.

Currently, the method effectively to defrost in double-stage compressive refrigerating system has single stage compress heat pump cycle method, i.e., original double The pipeline for connecting evaporator inlet-outlet is divided into refrigeration branch and defrosting branch, evaporator defrosting in grade compression refrigerating system Pipeline connects the exhaust end of high pressure stage compressor or low-pressure stage compressor, and evaporator outlet connects the larger gas-liquid separation of volume Device.When evaporator needs refrigeration, by the switching of valve, refrigeration branch is made to connect evaporator, evaporator refrigeration.Evaporator needs When defrosting, by the switching of valve, defrosting branch is made to connect evaporator, defrosted for evaporator.Due to this Defrost method except Single stage compress heat pump cycle is run when white participates in single-stage pressure when two-stage compression refrigeration cycle turns single machine compressing hot pump defrosting cycle The great increase of pressure difference of the compressor operating of contracting heat pump cycle defrosting, can be caused to impact to compressor, damage compressor, and this The Temperature of Working that single stage compress Defrost is recycled into evaporator defrosting is low, and defrosting speed is slow, the diffusion of evaporator ambient heat Time it is long, cause defrosting efficiency to reduce；In addition when defrosting for evaporator, a large amount of liquid working substance streams for having been condensed by evaporator Enter gas-liquid separator, these liquid working substances pass through long-term accumulation, are easily sucked by low-pressure stage compressor, form compressor wet pressing Contracting, causes compressor to damage, and forms economic loss.

In addition, existing freezer can only generally realize single refrigeration temperature, needs to provide refrigerator according to using or freeze Between cold, it is inconvenient to use.

Invention content

Low-pressure stage compressor is used in view of the technical drawbacks of the prior art, it is an object of the present invention to provide a kind of Heat pump cycle defrosts for low-temperature evaporation device wheel shelves, avoids generating temperature fluctuation, defrosting efficiency is high, can improve compressor stability Second throttle among not exclusively cooling refrigeration system operation method.

It is a further object to provide a kind of defrosting efficiency height, and temperature fluctuation is small, stable, while can carry For double-stage compressive refrigerating system not exclusively cooling among the second throttle of refrigerator and the cold of guick freezing room.

The technical solution adopted to achieve the purpose of the present invention is：

A kind of operation method of the not exclusively cooling refrigeration system in second throttle centre, in being arranged in each low-pressure stage unit Warm evaporator and cryogenic vaporizer, the medium temperature evaporator freeze for realizing medium temperature, and the cryogenic vaporizer is for realizing low Temperature refrigeration or defrosting, the operation method include the following steps：When all low-pressure stage units realize refrigerating function, the medium temperature is steamed Middle pressure saturated liquid working medium is flashed to middle pressure saturated vapor by hair device, realizes medium temperature refrigeration；The cryogenic vaporizer is by low pressure liquid Body working medium flashes to low-pressure steam, realizes cryogenic refrigeration；When there is cryogenic vaporizer to need defrosting, by valve transfer, realize The low-pressure stage compressor of defrosting function is converted into high pressure stage compressor operation, realizes the low temperature in the low-pressure stage unit of defrosting function Compressor is absorbed presses through heat steam in the low-pressure stage compressor of low-pressure stage unit for realizing refrigerating function, or absorbs and From the mixing hot gas of intercooler and the low-pressure stage compressor for realizing refrigerating function, it is sent into after compression to be defrosted described low Warm evaporator, the condensation heating cryogenic vaporizer realize defrosting, realize the cryogenic vaporizer in the low-pressure stage unit of refrigerating function Still refrigerating function is realized；It waits after defrosting, realizes that the low-pressure stage unit of defrosting function by valve transfer, realizes refrigeration work( Energy.

A kind of not exclusively cooling refrigeration system in the second throttle centre using Defrost for realizing above-mentioned operation method, packet Include high pressure stage compressor group, condenser, first throttle valve, intercooler and multiple low-pressure stage units；Each low-pressure stage Unit includes low-pressure stage compressor, the first four-way reversing valve, second throttle, cryogenic vaporizer, medium temperature evaporator, first unidirectional Valve and the second check valve；The suction end of the low-pressure stage compressor is connect with the 4th interface of first four-way reversing valve, institute The exhaust end for stating low-pressure stage compressor is connect with the second interface of first four-way reversing valve, first four-way reversing valve Third interface is connect with the import of first check valve and the outlet of second check valve respectively, the first four-way commutation The first interface of valve is connect through the cryogenic vaporizer with the first interface of the second throttle；The of the medium temperature evaporator One interface is connected in parallel and is connect with the air inlet of the intercooler, the second interface of the second throttle and described The second interface of medium temperature evaporator is connect after being connected in parallel with the liquid outlet of the intercooler, first check valve Outlet, the import of second check valve and the high pressure stage compressor group suction end be connected in parallel after with the centre The gas outlet of cooler connects；The high pressure stage compressor group exhaust end is through the condenser, first throttle valve and the centre The inlet of cooler connects.

A kind of not exclusively cooling refrigeration system in the second throttle centre using Defrost for realizing above-mentioned operation method, packet Include high pressure stage compressor group, condenser, first throttle valve, intercooler and multiple low-pressure stage units；Each low-pressure stage Unit includes low-pressure stage compressor, the first four-way reversing valve, the second four-way reversing valve, second throttle, cryogenic vaporizer, medium temperature Evaporator, the first check valve and the second check valve；The suction end of the low-pressure stage compressor and first four-way reversing valve 4th interface connects, and the exhaust end of the low-pressure stage compressor is connect with the second interface of first four-way reversing valve, described The third interface of first four-way reversing valve is connect with the import of first check valve and the outlet of second check valve respectively, The first interface of first four-way reversing valve is connect through the cryogenic vaporizer with the first interface of the second throttle, institute The second interface for stating second throttle is connect with the second interface of second four-way reversing valve；The first of the medium temperature evaporator Interface is connect after being connected in parallel with the air inlet of the intercooler, the second interface of the medium temperature evaporator and described the The third interfaces of two four-way reversing valves connects, after the first interface and the 4th interface of second four-way reversing valve are connected in parallel It is connect with the liquid outlet of the intercooler；The exporting of first check valve, the import of second check valve and institute State high pressure stage compressor group suction end be connected in parallel after connect with the gas outlet of the intercooler；The hiigh pressure stage pressure The exhaust end of contracting unit is connect through the condenser, first throttle valve with the inlet of the intercooler.

A kind of not exclusively cooling refrigeration system in the second throttle centre using Defrost for realizing above-mentioned operation method, packet Include high pressure stage compressor group, condenser, first throttle valve, intercooler, two-way valve and multiple low-pressure stage units；It is each described Low-pressure stage unit includes low-pressure stage compressor, the first four-way reversing valve, second throttle, cryogenic vaporizer, medium temperature evaporator, One check valve and the second check valve；The suction end of the low-pressure stage compressor and the 4th interface of first four-way reversing valve connect It connects, the exhaust end of the low-pressure stage compressor is connect with the second interface of first four-way reversing valve, and first four-way changes It is connect respectively with the import of first check valve and the outlet of second check valve to the third interface of valve, the described 1st The first interface of logical reversal valve is connect through the cryogenic vaporizer with the first interface of the second throttle；The medium temperature evaporation The first interface of device is connect after being connected in parallel with the air inlet of the intercooler, the second interface of the second throttle And the second interface of the medium temperature evaporator be connected in parallel after connect with the liquid outlet of the intercooler, described first is single Pass through after being connected in parallel to the suction end of the exporting of valve, the import of second check valve and the high pressure stage compressor group The two-way valve is connect with the gas outlet of the intercooler；The exhaust end of the high pressure stage compressor group is through the condensation Device, first throttle valve are connect with the inlet of the intercooler.

A kind of not exclusively cooling refrigeration system in the second throttle centre using Defrost for realizing above-mentioned operation method, packet Include high pressure stage compressor group, condenser, first throttle valve, intercooler, two-way valve and multiple low-pressure stage units；It is each described Low-pressure stage unit includes low-pressure stage compressor, the first four-way reversing valve, the second four-way reversing valve, second throttle, low-temperature evaporation Device, medium temperature evaporator, the first check valve and the second check valve；The suction end of the low-pressure stage compressor is changed with first four-way It is connected to the 4th interface of valve, the exhaust end of the low-pressure stage compressor and the second interface of first four-way reversing valve connect It connects, the third interface of first four-way reversing valve goes out with the import of first check valve and second check valve respectively Mouth connection, first interface of the first interface through the cryogenic vaporizer Yu the second throttle of first four-way reversing valve Connection, the second interface of the second throttle are connect with the second interface of second four-way reversing valve；The medium temperature evaporation The first interface of device is connect after being connected in parallel with the air inlet of the intercooler, the second interface of the medium temperature evaporator It is connect with the third interface of second four-way reversing valve, the first interface of second four-way reversing valve and the 4th interface are in parallel It is connect with the liquid outlet of the intercooler after together；The exporting of first check valve, second check valve into Mouthful and the high pressure stage compressor group suction end be connected in parallel after by the two-way valve and the intercooler Gas outlet connects；The exhaust end of the high pressure stage compressor group is through the condenser, first throttle valve and the intercooler Inlet connection.

The high pressure stage compressor group includes one or more high pressure stage compressor, and particular number is transported according to the refrigeration system Row operating mode determines that when using more high pressure stage compressors, the air-breathing interface parallel connection of every high pressure stage compressor is as institute The suction end of high pressure stage compressor group is stated, the exhaust port parallel connection of every high pressure stage compressor is compressed as the hiigh pressure stage The exhaust end of unit.

The quantity at least three of the low-pressure stage unit.

Compared with prior art, the beneficial effects of the invention are as follows：

1, it in the operation method of refrigeration system of the invention, realizes the refrigeration of low-pressure stage unit by the switching of valve and removes The conversion of white pattern.In defrost mode, realize that the low-pressure stage compressor of defrosting function is converted into high pressure stage compressor operation, it is real Now the cryogenic compressor in the low-pressure stage unit of defrosting function absorbs the middle pressure from the low-pressure stage compressor for realizing refrigerating function Superheated vapor or from intercooler with refrigeration low-pressure stage compressor mixed vapour, realize low-pressure stage unit inverse cycle remove Frost, cycle when cycle and refrigeration when defrosting is two-stage compression cycle, and then forms a dynamic cooling system, temperature wave Dynamic small, defrosting efficiency is high, energy saving.Meanwhile compressor can stable operation, improve the service life of system.

2, refrigeration system of the invention passes through valve transfer when there is cryogenic vaporizer defrosting in low-pressure stage unit, realizes The refrigeration of low-pressure stage unit and the conversion of defrosting mode realize the low-pressure stage compressor conversion of defrosting function in defrost mode It is run at high pressure stage compressor, defrosting cycle and refrigeration cycle are two-stage compression cycles, and then form a dynamic refrigeration system System, using more flexible convenience, defrosting efficiency is high, has saved the energy.

3, in refrigeration system of the invention, low-pressure stage compressor is converted to high pressure when the evaporator in low-pressure stage unit defrosts Grade compressor operating, the defrosting cycle operation of low-pressure stage unit are pressed in centre between high pressure, and low-pressure stage unit is followed by freezing When ring is changed into defrosting cycle, the pressure difference variation to work between the compressor suction and discharge in low-pressure stage unit is smaller, and compressor dissipates It is hot more preferable, be conducive to protect compressor, the service life of compressor is provided.

4, in refrigeration system of the invention, the origin of heat refrigeration low-pressure stage unit of the evaporator defrosting in low-pressure stage unit In evaporator and compressor input work, heat when defrosting is in liberal supply, unrestricted, can fully defrost, defrosting effect Rate higher is more suitable in large-scale double-stage compressive refrigerating system.

5, in refrigeration system of the invention, low-pressure stage compressor heat pump circulation is used to defrost for low-temperature evaporation device wheel shelves, together When, during defrosting, low-pressure stage compressor is converted to high pressure stage compressor operation successively, convenient for compressor lubrication of just arbitrarily downgrading Oily oil return is uniform, and compressor abrasion degree of just arbitrarily downgrading is uniform, and simple system is efficient.Be separately provided defrosting evaporator and Individually the refrigeration system of defrosting branch is compared, and structure is simpler, reduces system initial cost.

6, the cryogenic vaporizer defrosting in refrigeration system of the invention uses inverse circulating heat pump defrosting, adds from frost layer inside Heat, frost is easy to fall off from cooling surface, so the heat ratio theoretical value actually to defrost is much smaller.Meanwhile frost layer is melted by interior To outer, there is no vapor to be escaped to outside evaporator at defrosting initial stage.Only after frost thawing falls off, the outside spoke of heat ability on ribbed pipe It penetrates, but the stage of defrosting at this time also tends to terminate, therefore few with the heat exchange amount of Ku Nei and surrounding building enclosure, defrosting efficiency compares It is high.

7, refrigeration system mesohigh grade compressor number of the invention is unlimited, low-pressure stage unit number at least three, can be with According to different working condition requirements, different refrigeration requirements is realized variable-flow cycle of just arbitrarily downgrading, is matched between just arbitrarily downgrading grade most Good capacity ratio.

8, refrigeration system of the invention can produce the refrigerating capacity under two kinds of evaporating temperatures simultaneously, particularly suitable for freezer The cold of refrigerator and guick freezing room is provided simultaneously in system.

9, in refrigeration system of the invention, when having, when cryogenic vaporizer defrosts in low-pressure stage unit, defrost low-pressure stage unit The origin of heat of cryogenic vaporizer defrosting presses through hot gas in being, that is, the low-pressure stage unit mesolow grade compressor that defrosts is directly from system Cold low grade unit low-pressure stage compressor air-discharging end sucks the higher middle pressure steam of the degree of superheat, through the low-pressure stage unit low-pressure stage that defrosts The high-pressure working medium temperature higher of compressor discharge, into the Temperature of Working higher of defrosting low-pressure stage unit cryogenic vaporizer, defrosting Effect is more preferable, and defrosting speed is faster.

Description of the drawings

The non-full liquid type that Fig. 1 show the hot gas defrosting of the embodiment of the present invention 1 has medium temperature evaporation using Defrost The structure principle chart of double-stage compressive refrigerating system not exclusively cooling among the second throttle of device；

The full liquid type that Fig. 2 show the hot gas defrosting of the embodiment of the present invention 2 has medium temperature evaporator using Defrost Second throttle among not exclusively cooling double-stage compressive refrigerating system structure principle chart；

Fig. 3 show the non-full liquid type of the high temperature hot gas defrosting of the embodiment of the present invention 3 using the discharge of low-pressure stage compressor The structure of the double-stage compressive refrigerating system not exclusively cooled down among the second throttle with medium temperature evaporator of high temperature hot gas defrosting Schematic diagram；

Fig. 4 show the height that the full liquid type of the high temperature hot gas defrosting of the embodiment of the present invention 4 uses low-pressure stage compressor to be discharged The structure of not exclusively cooling double-stage compressive refrigerating system is former among the second throttle with medium temperature evaporator of warm hot gas defrosting Reason figure；

Fig. 5 show intercooler interface diagram.

Specific implementation mode

Below in conjunction with the drawings and specific embodiments, the present invention is described in detail.

The present invention designing points be：One low-pressure stage compressor string, one cryogenic vaporizer when defrosting, is cut by valve It changes, low-pressure stage compressor becomes high pressure stage compressor, and high pressure stage compressor part originally, which is shut down or all shut down, not to be had to, in making The low-pressure stage compressor sucking that pressure steam working medium is defrosted, the evaporator of defrosting are converted to Two-stage Compression condenser, one by one (or Group) defrosting, after having defrosted, each evaporator refrigeration is carried out by valve transfer.Specific technical solution is such as：

The operation method of not exclusively cooling refrigeration system, sets in each low-pressure stage unit among the second throttle of the present invention Medium temperature evaporator and cryogenic vaporizer are set, the medium temperature evaporator freezes for realizing medium temperature, and the cryogenic vaporizer is for real Existing cryogenic refrigeration or defrosting, the operation method include the following steps：When all low-pressure stage units realize refrigerating function, in described Middle pressure saturated liquid working medium is flashed to middle pressure saturated vapor by warm evaporator, realizes medium temperature refrigeration；The cryogenic vaporizer will be low Press liquid working medium flashes to low-pressure steam, realizes cryogenic refrigeration；When there is cryogenic vaporizer to need defrosting, by valve transfer, Realize that the low-pressure stage compressor of defrosting function is converted into high pressure stage compressor operation, in the low-pressure stage unit for realizing the function that defrosts Cryogenic compressor is absorbed presses through heat steam in the low-pressure stage compressor for realizing refrigerating function, or absorbs from intermediate cold But the mixing hot gas of device and the low-pressure stage compressor for realizing refrigerating function, is sent into cryogenic vaporizer to be defrosted after compression, cold The solidifying cryogenic vaporizer that heats realizes defrosting, realizes that the cryogenic vaporizer in the low-pressure stage unit of refrigerating function still realizes refrigeration Function；It waits after defrosting, realizes that the low-pressure stage unit of defrosting function by valve transfer, realizes refrigerating function；It is multiple when having When the cryogenic vaporizer needs defrosting, defrosting is realized by taking turns shelves mode.

In the present invention, high pressure stage compressor quantity in high pressure stage compressor group is one or more, low-pressure stage unit number Amount is at least three.When high pressure stage compressor quantity is 1, and low-pressure stage unit is three, reverse cycle defrosting needs are realized High pressure stage compressor is shut down.Attached drawing is to contain high pressure stage compressor 2 in high pressure stage compressor group, and low-pressure stage unit is 4, such as Two high pressure stage compressors are all shut down when one low-pressure stage unit defrosting of fruit, then operation proportioning of just arbitrarily downgrading is 1：3, if one One high pressure stage compressor runs another shutdown when a low-pressure stage unit defrosting, then operation proportioning of just arbitrarily downgrading is 2：3.If There are 3 high pressure stage compressors in high pressure stage compressor group, low-pressure stage unit 6, when defrosting, operation proportioning of just arbitrarily downgrading type is more It is more.During defrosting, high pressure stage compressor whether shut down or part shut down according to just arbitrarily downgrade head proportioning, specific operating mode with And defrosting quality etc. determines.

When there is cryogenic vaporizer 6-1 described in low-pressure stage unit to need defrosting, high pressure stage compressor part originally is stopped Machine or all shut down does not have to, the low-pressure stage compressor sucking for making middle pressure steam working medium be defrosted, when having in multiple low-pressure stage units When the cryogenic vaporizer 6-1 needs defrosting, using wheel shelves Defrost mode, i.e., low temperature steams described in one defrosting low-pressure stage unit It is immediately converted as refrigeration low-pressure stage unit after the 6-1 defrostings of hair device, is removed for cryogenic vaporizer 6-1 described in other low-pressure stage units Frost, multiple cryogenic vaporizer 6-1 defrost one by one, wait for that all cryogenic vaporizer 6-1 defrostings are completed, all low pressure Grade cell translation is refrigeration low-pressure stage unit, the high pressure stage compressor 1-2 bootings.

The operation method of the present invention can be realized by following refrigeration systems：

The present invention is using not exclusively cooling refrigeration system root among the second throttle with medium temperature evaporator of Defrost According to when there is cryogenic vaporizer defrosting in low-pressure stage unit, pressed with medium temperature evaporator before low-pressure stage unit second throttle of freezing The state of working medium is divided into full liquid liquid-supplying type and non-full liquid liquid-supplying type.Wherein, enter cryogenic vaporizer in the system of full liquid liquid-supplying type Low with the working medium mass dryness fraction of medium temperature evaporator, heat exchange efficiency is high, and cryogenic vaporizer and the heat exchanger area that medium temperature evaporator needs are small. The system structure of non-full liquid liquid-supplying type is simple, and parts are less, and cost is lower.

The present invention is using refrigeration system not exclusively cooling among the second throttle with medium temperature evaporator of Defrost In, when there is in low-pressure stage unit cryogenic vaporizer defrost, by valve transfer, the low-pressure stage unit mesolow grade compressor from Heat steam is pressed through in intercooler sucking, can also suck in being cooled down without intercooler and press through heat steam.Work as suction Enter the degree of superheat that mixes of middle pressure saturated vapor not come out with intercooler cooling gas outlet it is higher in press through heat steam, in The hot gas for pressing through higher temperature of the heat steam through the low-pressure stage unit low pressure compressor sucking compression discharge that defrosts, into defrosting low pressure The Temperature of Working higher of grade unit cryogenic vaporizer, defrosting effect is more preferable, and defrosting speed is faster.When low in all low-pressure stage units When warm evaporator need not all defrost, by valve transfer, high pressure stage compressor is drawn through the middle pressure of intercooler cooling Saturated vapor, the hot air temperature that middle pressure saturated vapor sucks compression discharge through high pressure stage compressor is relatively low, and condensation effect is good, refrigeration It is efficient.

It is divided into embodiment 1,2 embodiments 3,4 according to the difference of the middle pressure working medium of sucking.Wherein, embodiment 1 and embodiment 2 For defrosting when sucking from refrigeration low-pressure stage unit outflow in press through hot working fluid with from intercooler cool down gas outlet come out The technical solution of middle pressure saturated vapor mixed vapour, embodiment 3 and embodiment 4 are to be sucked not by the closing selection of two-way valve 8 The higher middle pressure steam of the degree of superheat mixed with the middle pressure saturated vapor that intercooler cooling gas outlet comes out, sucking mixing are steamed The refrigeration effect of gas is more preferable, and sucking is more preferable without the defrosting effect of the middle pressure steam of mixing.

Embodiment 1

The non-full liquid type of hot gas defrosting of the present invention is using not exclusively cooling refrigeration system among the second throttle of Defrost Structural schematic diagram as shown in Fig. 2, including high pressure stage compressor group, condenser 5, first throttle valve 4-1, intercooler 3 and Multiple low-pressure stage units.In the present embodiment, the high pressure stage compressor group includes one or more high pressure stage compressor 1-2, when When using more high pressure stage compressors, the air-breathing interface parallel connection of every high pressure stage compressor 1-2 is as the hiigh pressure stage pressure The suction end of contracting unit, the exhaust port parallel connection of every high pressure stage compressor 1-2 is as the high pressure stage compressor group Exhaust end.Each low-pressure stage unit include low-pressure stage compressor 1-1, the first four-way reversing valve 2-1, second throttle 4-2, Cryogenic vaporizer 6-1, medium temperature evaporator 6-2, the first check valve 7-1 and the second check valve 7-2.The low-pressure stage compressor 1-1 Suction end connect with the 4th interface of the first four-way reversing valve 2-1, the exhaust end of the low-pressure stage compressor 1-1 and institute State the second interface connection of the first four-way reversing valve 2-1, the third interface of the first four-way reversing valve 2-1 is respectively with described the The import of one check valve 7-1 and the outlet of the second check valve 7-2 connection, the first of the first four-way reversing valve 2-1 connects Mouth is connect through the cryogenic vaporizer 6-1 with the first interface of the second throttle 4-2；The of the medium temperature evaporator 6-2 One interface is connected in parallel and is connect with the air inlet 3-1 of the intercooler 3, and the second of the second throttle 4-2 connects The second interface of mouth and the medium temperature evaporator 6-2 are connect after being connected in parallel with the liquid outlet 3-4 of the intercooler 3, The suction end of the exporting of the first check valve 7-1, the import of the second check valve 7-2 and the high pressure stage compressor group It is connect with the gas outlet 3-2 of the intercooler 3 after being connected in parallel.The high pressure stage compressor group exhaust end is through described cold Condenser 5, first throttle valve 4-1 are connect with the inlet 3-3 of the intercooler 3.

The low-pressure stage unit can be used for refrigeration cycle or defrosting cycle, for being operated in Two-stage Compression when refrigeration cycle In low-pressure stage system, i.e., the cryogenic vaporizer refrigeration in the low-pressure stage unit is defined as refrigeration low-pressure stage unit.It is followed for defrosting It is operated in when ring in the hiigh pressure stage system of Two-stage Compression, i.e., the cryogenic vaporizer defrosting in the low-pressure stage unit is defined as defrosting Low-pressure stage unit.

When cryogenic vaporizer need not all defrost in low-pressure stage unit, all low-pressure stage units are used for refrigeration cycle, i.e., All low-pressure stage units are refrigeration low-pressure stage unit.Freeze low-pressure stage unit in the first four-way reversing valve 2-1 first interface with The connection of 4th interface, second interface and third interface connect.It is not exclusively cooling double among second throttle with medium temperature evaporator Grade compression refrigeration cycle thermal procession is as follows：Low-pressure stage compressor 1-1 in refrigeration low-pressure stage unit is changed through first four-way Low-pressure steam is sucked from the cryogenic vaporizer 6-1 to valve 2-1, low-pressure steam is compressed through the low-pressure stage compressor 1-1 to be risen Heat steam is pressed through in becoming after pressure, steam is through the first four-way reversing valve 2-1 and the first check valve 7-1 and the cooling during rolling The gas outlet 3-2 of device 3 come out saturation in pressure steam mixing, be mixed into the degree of superheat it is smaller in press through heat steam by the high pressure Grade compressor set sucking, steam become height through the high pressure stage compressor 1-2 compression boostings in the high pressure stage compressor group and press through It is discharged into after heat steam in the condenser 5 and is condensed into highly pressurised liquid, highly pressurised liquid is through the first throttle valve 4-1 reducing pressure by regulating flow Become middle pressure damp steam and the intercooler 3 is entered by the inlet 3-3 of the intercooler 3.The cooling during rolling Middle a part of evaporation endothermic of press liquid working medium in device 3, the cooling 3 air inlet 3-1 of intercooler press through heat in coming in Steam.The middle pressure saturated liquid working medium come out from 3 liquid outlet 3-4 of the intercooler is divided into two-way, middle all the way to press saturated solution Body working medium, which enters in the medium temperature evaporator 6-2, evaporates, and absorbs the heat in medium temperature freezer, medium temperature refrigeration phenomenon is generated, from institute Stating the middle pressure saturated vapor that medium temperature evaporator 6-2 comes out, by the air inlet 3-1 of the intercooler 3 to return to the centre cold But device 3；The middle pressure saturated liquid working medium that another part comes out from 3 liquid outlet 3-4 of the intercooler throttles through described second Valve 4-2 reducing pressure by regulating flow becomes low pressure damp steam into evaporating in the cryogenic vaporizer 6-1, absorbs the heat in low-temperature cold store, Cryogenic refrigeration phenomenon is generated, the low-pressure steam from the cryogenic vaporizer 6-1 out is returned through the first four-way reversing valve 2-1 To the suction end of the low-pressure stage compressor 1-1, not exclusively cooling twin-stage among the second throttle with medium temperature evaporator is completed Compress refrigeration cycle.

When having, when cryogenic vaporizer needs defrosting in low-pressure stage unit, corresponding low-pressure stage unit is defrosting low-pressure stage list Member, remaining low-pressure stage unit are refrigeration low-pressure stage unit.Defrost the of the first four-way reversing valve 2-1 described in low-pressure stage unit One interface is connect with second interface, third interface is connect with the 4th interface, the first four-way commutation described in low-pressure stage unit of freezing The first interface of valve 2-1 is connect with the 4th interface, second interface and third interface connect.It is above-mentioned with medium temperature evaporator two Among secondary throttling on not exclusively cooling two-stage compression refrigeration cycle heating power process basis, the low temperature described in low-pressure stage unit that defrosts steams It is as follows to send out device defrosting thermal procession：From the gas outlet 3-2 of intercooler come out middle pressure saturated vapor with from refrigeration low-pressure stage The exhaust end of low-pressure stage compressor in unit presses through during the larger superheated vapor mixing of temperature becomes in being discharged and presses through temperature Smaller superheated vapor is defrosted the low-pressure stage compressor 1-1 in low-pressure stage unit through the first four-way reversing valve 2-1 And the second check valve 7-2 sucking, steam become high pressure superheated vapor after low-pressure stage compressor 1-1 compression boostings and are discharged into It is condensed in the cryogenic vaporizer 6-1, heats the cryogenic vaporizer 6-1, the defrosting for generating the cryogenic vaporizer 6-1 is existing As, the highly pressurised liquid working medium being condensed into through the second throttle 4-2 reducing pressure by regulating flow become middle pressure damp steam with from described Between 3 liquid outlet 3-4 of cooler come out middle press liquid mixing, be mixed into damp steam into the medium temperature evaporator 6-2 with refrigeration In second throttle 4-2 described in low-pressure stage unit, complete using the defrosting of low-pressure stage compressor heat pump circulation there is medium temperature to steam Send out not exclusively cooling two-stage compression refrigeration cycle among the second throttle of device.

Embodiment 2

The full liquid type of hot gas defrosting of the present invention is using not exclusively cooling refrigeration system among the second throttle of Defrost Structural schematic diagram is as shown in Fig. 2, including high pressure stage compressor group, condenser 5, first throttle valve 4-1, intercooler 3 and more A low-pressure stage unit.In the present embodiment, the high pressure stage compressor group includes one or more high pressure stage compressor 1-2, when adopting When with more high pressure stage compressor 1-2, the air-breathing interface parallel connection of every high pressure stage compressor 1-2 is as the hiigh pressure stage pressure The suction end of contracting unit, the exhaust port parallel connection of every high pressure stage compressor 1-2 is as the high pressure stage compressor group Exhaust end.Each low-pressure stage unit includes low-pressure stage compressor 1-1, the first four-way reversing valve 2-1, the second four-way reversing valve 2-2, second throttle 4-2, cryogenic vaporizer 6-1, medium temperature evaporator 6-2, the first check valve 7-1 and the second check valve 7-2.Institute The suction end for stating low-pressure stage compressor 1-1 is connect with the 4th interface of the first four-way reversing valve 2-1, the low-pressure stage compression The exhaust end of machine 1-1 is connect with the second interface of the first four-way reversing valve 2-1, and the of the first four-way reversing valve 2-1 Three interfaces are connect with the import of the first check valve 7-1 and the outlet of the second check valve 7-2 respectively, first four-way The first interface of reversal valve 2-1 is connect through the cryogenic vaporizer 6-1 with the first interface of the second throttle 4-2, described The second interface of second throttle 4-2 is connect with the second interface of the second four-way reversing valve 2-2；The medium temperature evaporator 6- 2 first interface is connect after being connected in parallel with the air inlet 3-1 of the intercooler 3, and the of the medium temperature evaporator 6-2 Two interfaces are connect with the third interface of the second four-way reversing valve 2-2, the first interface of the second four-way reversing valve 2-2 and 4th interface is connect after being connected in parallel with the liquid outlet 3-4 of the intercooler 3；The outlet of the first check valve 7-1, The import of the second check valve 7-2 and the suction end of the high pressure stage compressor group are cold with the centre after being connected in parallel But the gas outlet 3-2 connections of device 3；The exhaust end of the high pressure stage compressor group through the condenser 5, first throttle valve 4-1 with The inlet 3-3 connections of the intercooler 3.

When cryogenic vaporizer need not all defrost in low-pressure stage unit, all low-pressure stage units are used for refrigeration cycle, i.e., All low-pressure stage units are refrigeration low-pressure stage unit.The first of first four-way reversing valve 2-1 described in refrigeration low-pressure stage unit connects Mouth is connect with the 4th interface, second interface and third interface connect, the first interface and second of the second four-way reversing valve 2-2 Interface connection, third interface are connect with the 4th interface.Not exclusively cooling twin-stage among second throttle with medium temperature evaporator 6-2 It is as follows to compress refrigeration cycle thermal procession：Low-pressure stage unit mesolow grade compressor 1-1 freeze through first four-way reversing valve 2-1 sucks low-pressure steam from the cryogenic vaporizer 6-1, and the first steam is after low-pressure stage compressor 1-1 compression boostings Heat steam is pressed through in becoming, in press through heat steam through the first four-way reversing valve 2-1 and the first check valve 7-1 with from described Between cooler 3 gas outlet 3-2 come out saturation in pressure steam mixing；Be mixed into the degree of superheat it is smaller in press through heat steam by institute State high pressure stage compressor group suction end sucking, in press through heat steam through the high pressure stage compressor in the high pressure stage compressor group Become being discharged into the condenser 5 after high pressure superheated vapor being condensed into highly pressurised liquid after 1-2 compression boostings；It is flowed from condenser 5 The highly pressurised liquid gone out through the first throttle valve 4-1 reducing pressure by regulating flow become middle pressure damp steam by the intercooler 3 into Liquid mouth 3-3 enters the intercooler 3.Middle a part of evaporation endothermic of press liquid working medium in the intercooler 3, it is cooling 3 air inlet 3-1 of the intercooler presses through heat steam in coming in.The middle pressure that 3 liquid outlet 3-4 of the intercooler comes out Saturated liquid working medium is divided into two-way, and middle pressure saturated liquid working medium is evaporated through the second four-way reversing valve 2-2 into the medium temperature all the way It is evaporated in device 6-2, absorbs the heat in medium temperature freezer, medium temperature refrigeration phenomenon is generated, from the medium temperature evaporator 6-2 comes out Pressure saturated vapor returns to the intercooler 3 by the air inlet 3-1 of the intercooler 3；It is intermediate described in another part The middle pressure saturated liquid working medium that 3 liquid outlet 3-4 of cooler comes out is through the second four-way reversing valve 2-2 and second throttle 4-2 Reducing pressure by regulating flow becomes low pressure damp steam into evaporating in the cryogenic vaporizer 6-1, absorbs the heat in low-temperature cold store, generates low Temperature refrigeration phenomenon, the low-pressure steam from the cryogenic vaporizer 6-1 out return to described through the first four-way reversing valve 2-1 The suction end of low-pressure stage compressor 1-1 completes not exclusively cooling Two-stage Compression system among the second throttle with medium temperature evaporator SAPMAC method.

When having, when cryogenic vaporizer needs defrosting in low-pressure stage unit, corresponding low-pressure stage unit is defrosting low-pressure stage list Member, remaining low-pressure stage unit are refrigeration low-pressure stage unit.Defrost the first four-way reversing valve 2-1 first described in low-pressure stage unit Interface is connect with second interface, third interface is connect with the 4th interface, the second four-way reversing valve 2-2 first interfaces and the 4th Interface connection, second interface and third interface connect.Freeze the first four-way reversing valve 2-1 and the two or four described in low-pressure stage unit The connecting interface of logical reversal valve 2-2 is constant.The not exclusively cooling twin-stage pressure among the above-mentioned second throttle with medium temperature evaporator On the basis of contraction SAPMAC method thermal procession, the thermal procession of cryogenic vaporizer defrosting described in low-pressure stage unit that defrosts is as follows：Therefrom Between cooler gas outlet 3-2 come out middle pressure saturated vapor with from refrigeration low-pressure stage unit in low-pressure stage compressor exhaust It presses through the smaller superheated vapor of temperature in pressing through the larger superheated vapor mixing of temperature in the discharge of end and becoming and is defrosted low-pressure stage The low-pressure stage compressor 1-1 in unit is through the first four-way reversing valve 2-1 and the second check valve 7-2 suckings, steam warp Become high pressure superheated vapor after low-pressure stage compressor 1-1 compression boosting and be discharged into the cryogenic vaporizer 6-1 to condense, add The heat cryogenic vaporizer 6-1, generates the defrosting phenomenon of the cryogenic vaporizer 6-1, the highly pressurised liquid working medium warp being condensed into The second throttle 4-2 reducing pressure by regulating flow becomes middle pressure damp steam, and middle pressure damp steam is through described in the second four-way reversing valve 2-2 entrance The 6-2 evaporations of medium temperature evaporator, complete the second throttle with medium temperature evaporator using the defrosting of low-pressure stage compressor heat pump circulation Intermediate not exclusively cooling two-stage compression refrigeration cycle.

Embodiment 3

The non-full liquid type of high temperature hot gas defrosting of the present invention is using not exclusively cooling refrigeration among the second throttle of Defrost The schematic diagram of system is as shown in figure 3, including high pressure stage compressor group, condenser 5, first throttle valve 4-1, intercooler 3, two Port valve 8 and multiple low-pressure stage units.In the present embodiment, the high pressure stage compressor group includes one or more high pressure stage compressor 1-2, when using more high pressure stage compressors, the air-breathing interface parallel connection of every high pressure stage compressor 1-2 is as the height The exhaust port parallel connection of the suction end for compressor set of arbitrarily downgrading, every high pressure stage compressor 1-2 is compressed as the hiigh pressure stage The exhaust end of unit.Each low-pressure stage unit includes low-pressure stage compressor 1-1, the first four-way reversing valve 2-1, the second throttling Valve 4-2, cryogenic vaporizer 6-1, medium temperature evaporator 6-2, the first check valve 7-1 and the second check valve 7-2；The low-pressure stage compression The suction end of machine 1-1 is connect with the 4th interface of the first four-way reversing valve 2-1, the exhaust of the low-pressure stage compressor 1-1 End is connect with the second interface of the first four-way reversing valve 2-1, the third interface of the first four-way reversing valve 2-1 respectively with The import of the first check valve 7-1 and the outlet of the second check valve 7-2 connection, the first four-way reversing valve 2-1's First interface is connect through the cryogenic vaporizer 6-1 with the first interface of the second throttle 4-2；The medium temperature evaporator 6- 2 first interface is connect after being connected in parallel with the air inlet 3-1 of the intercooler 3, and the of the second throttle 4-2 The second interface of two interfaces and the medium temperature evaporator 6-2 connect after being connected in parallel with the liquid outlet 3-4 of the intercooler 3 It connects, the exporting of the first check valve 7-1, the import of the second check valve 7-2 and the suction of the high pressure stage compressor group Gas end is connect by the two-way valve 8 with the gas outlet 3-2 of the intercooler 3 after being connected in parallel；The hiigh pressure stage pressure The exhaust end of contracting unit is connect through the condenser 5, first throttle valve 4-1 with the inlet 3-3 of the intercooler 3.

When cryogenic vaporizer need not all defrost in low-pressure stage unit, all low-pressure stage units are used for refrigeration cycle, i.e., All low-pressure stage units are refrigeration low-pressure stage unit.Freeze low-pressure stage unit in the first four-way reversing valve 2-1 first interface with The connection of 4th interface, second interface and third interface connect, and two-way valve 8 is opened.Among second throttle with medium temperature evaporator Not exclusively cooling two-stage compression refrigeration cycle thermal procession is as follows：Freeze described in low-pressure stage unit mesolow grade compressor 1-1 warps First four-way reversing valve 2-1 sucks low-pressure steam from the cryogenic vaporizer 6-1, and steam is through the low-pressure stage compressor 1-1 Compression boosting after become in press through heat steam, in press through heat steam through the first four-way reversing valve 2-1, the first check valve 7-1 Steam is pressed to mix with from the saturation that the gas outlet 3-2 of the intercooler 3 outflows come out through the two-way valve 8；It is mixed into It presses through heat steam during the degree of superheat is smaller to be sucked by the suction end of the high pressure stage compressor group, steam is compressed through the hiigh pressure stage High pressure stage compressor 1-2 compressions in unit, which boost to be discharged into the condenser 5 after becoming high pressure superheated vapor, is condensed into height Press liquid, highly pressurised liquid become middle pressure damp steam through the first throttle valve 4-1 reducing pressure by regulating flow and pass through the intercooler 3 Inlet 3-3 enters in the intercooler 3.Middle a part of evaporation endothermic of press liquid working medium in the intercooler 3, The air inlet 3-1 of the cooling intercooler 3 presses through heat steam in coming in.3 liquid outlet 3-4 outflows of the intercooler The middle pressure saturated liquid working medium come is divided into two-way：Pressure saturated liquid working medium, which enters in the medium temperature evaporator 6-2, in all the way evaporates, The heat in medium temperature freezer is absorbed, medium temperature refrigeration phenomenon is generated, the middle pressure saturated vapor come out from the medium temperature evaporator 6-2 is logical The air inlet 3-1 for crossing the intercooler 3 returns to the intercooler 3；3 liquid outlet of intercooler described in another part Middle pressure saturated liquid working medium out becomes low pressure damp steam through the second throttle 4-2 reducing pressure by regulating flow and is steamed into the low temperature It is evaporated in hair device 6-1, absorbs the heat in low-temperature cold store, generate cryogenic refrigeration phenomenon, from the cryogenic vaporizer 6-1 out Low-pressure steam the suction end of the low-pressure stage compressor 1-1 is returned to through the first four-way reversing valve 2-1, complete that there is medium temperature Not exclusively cooling two-stage compression refrigeration cycle among the second throttle of evaporator.

When having, when cryogenic vaporizer needs defrosting in low-pressure stage unit, corresponding low-pressure stage unit is defrosting low-pressure stage list Member, remaining low-pressure stage unit are refrigeration low-pressure stage unit.Defrost the first four-way reversing valve 2-1 first described in low-pressure stage unit Interface is connect with second interface, third interface is connect with the 4th interface, and freeze the first four-way reversing valve described in low-pressure stage unit The connection relation of 2-1 is constant, and the two-way valve 8 is closed.It is not exclusively cold among the above-mentioned second throttle with medium temperature evaporator But on two-stage compression refrigeration cycle heating power process basis, the thermal procession of cryogenic vaporizer defrosting described in low-pressure stage unit is defrosted such as Under：The low-pressure stage compressor 1-1 in defrosting low-pressure stage unit is through the first four-way reversing valve 2-1 and the second check valve 7- 2 from the larger middle pressure steam of the exhaust end sucking degree of superheat of the low-pressure stage compressor 1-1 of refrigeration low-pressure stage unit, described in steam warp Become high pressure superheated vapor after low-pressure stage compressor 1-1 compression boosting and be discharged into the cryogenic vaporizer 6-1 to condense, heats institute Cryogenic vaporizer 6-1 is stated, the defrosting phenomenon of the cryogenic vaporizer 6-1 is generated, described in the highly pressurised liquid working medium warp being condensed into Second throttle 4-2 reducing pressure by regulating flow becomes middle pressure damp steam and the middle press liquid from 3 liquid outlet 3-4 of the intercooler out Mixing is mixed into damp steam into the second throttle 4-2 in the medium temperature evaporator 6-2 and the low-pressure stage unit that freezes In, it completes among the second throttle with medium temperature evaporator using the high temperature hot gas defrosting of low-pressure stage compressor discharge not exclusively Cooling two-stage compression refrigeration cycle.

Embodiment 4

The full liquid type of high temperature hot gas defrosting of the present invention is using not exclusively cooling refrigeration system among the second throttle of Defrost The structural schematic diagram of system as shown in figure 4, including high pressure stage compressor group, condenser 5, first throttle valve 4-1, intercooler 3, Two-way valve 8 and multiple low-pressure stage units.In the present embodiment, the high pressure stage compressor group includes the compression of one or more hiigh pressure stage Machine 1-2, when using more high pressure stage compressors, described in the air-breathing interface parallel connection conduct of every high pressure stage compressor 1-2 The suction end of high pressure stage compressor group, the exhaust port parallel connection of every high pressure stage compressor 1-2 is as the hiigh pressure stage pressure The exhaust end of contracting unit.Each low-pressure stage unit includes low-pressure stage compressor 1-1, the first four-way reversing valve 2-1, the two or four Logical reversal valve 2-2, second throttle 4-2, cryogenic vaporizer 6-1, medium temperature evaporator 6-2, the first check valve 7-1 and second are unidirectional Valve 7-2；The suction end of the low-pressure stage compressor 1-1 is connect with the 4th interface of the first four-way reversing valve 2-1, described low The exhaust end of compressor 1-1 of arbitrarily downgrading is connect with the second interface of the first four-way reversing valve 2-1, first four-way reversing valve The third interface of 2-1 is connect with the import of the first check valve 7-1 and the outlet of the second check valve 7-2 respectively, described First interface of the first interface of first four-way reversing valve 2-1 through the cryogenic vaporizer 6-1 and second throttle 4-2 connects It connects, the second interface of the second throttle 4-2 is connect with the second interface of the second four-way reversing valve 2-2；The medium temperature The first interface of evaporator 6-2 is connect after being connected in parallel with the air inlet 3-1 of the intercooler 3, the medium temperature evaporation The second interface of device 6-2 is connect with the third interface of the second four-way reversing valve 2-2, the second four-way reversing valve 2-2's First interface and the 4th interface are connect after being connected in parallel with the liquid outlet 3-4 of the intercooler 3；First check valve The suction end of the exporting of 7-1, the import of the second check valve 7-2 and the high pressure stage compressor group leads to after being connected in parallel The two-way valve 8 is crossed to connect with the gas outlet 3-2 of the intercooler；Described in the exhaust end warp of the high pressure stage compressor group Condenser 5, first throttle valve 4-1 are connect with the inlet 3-3 of the intercooler 3.

When cryogenic vaporizer need not all defrost in low-pressure stage unit, all low-pressure stage units are used for refrigeration cycle, i.e., All low-pressure stage units are refrigeration low-pressure stage unit.The first of first four-way reversing valve 2-1 described in refrigeration low-pressure stage unit connects Mouth is connect with the 4th interface, second interface and third interface connect, the first interface and second of the second four-way reversing valve 2-2 Interface connection, third interface are connect with the 4th interface, and two-way valve 8 is opened.It is endless among second throttle with medium temperature evaporator Complete cooling two-stage compression refrigeration cycle thermal procession is as follows：Low-pressure stage unit mesolow grade compressor 1-1 freeze through described first Four-way reversing valve 2-1 sucks low-pressure steam from the cryogenic vaporizer 6-1, and steam is compressed through the low-pressure stage compressor 1-1 Press through heat steam in becoming after boosting, steam through the first four-way reversing valve 2-1, the first check valve 7-1 with from the centre Pressure steam mixing in the saturation that the gas outlet 3-2 outflows of cooler 3 come out through the two-way valve 8；It is smaller to be mixed into the degree of superheat In press through heat steam by the high pressure stage compressor group suction end suck, hiigh pressure stage of the steam through the high pressure stage compressor group Become being discharged into the condenser 5 after high pressure superheated vapor after compressor 1-2 compression boosting being condensed into highly pressurised liquid；High pressure liquid Body becomes middle pressure damp steam through the first throttle valve 4-1 reducing pressure by regulating flow and is entered by the inlet 3-3 of the intercooler 3 The intercooler 3.Middle a part of evaporation endothermic of press liquid working medium in the intercooler 3, the cooling centre are cold But 3 air inlet 3-1 of device presses through heat steam in coming in.The middle pressure saturated liquid that 3 liquid outlet 3-4 of the intercooler is flowed out Working medium is divided into two-way：Pressure saturated liquid working medium enters in the medium temperature evaporator 6-2 through the second four-way reversing valve 2-2 and steams in all the way Hair absorbs the heat in medium temperature freezer, generates medium temperature refrigeration phenomenon, and the middle pressure come out from the medium temperature evaporator 6-2, which is saturated, steams Gas returns to the intercooler 3 by the air inlet 3-1 of the intercooler 3；Intercooler 3 described in another part goes out The middle pressure saturated liquid working medium that liquid mouth comes out becomes low through the second four-way reversing valve 2-2, second throttle 4-2 reducing pressure by regulating flow Pressure damp steam, which enters in the cryogenic vaporizer 6-1, to be evaporated, and is absorbed the heat in low-temperature cold store, is generated cryogenic refrigeration phenomenon, from Low-pressure steam in the cryogenic vaporizer 6-1 out returns to the low-pressure stage compressor through the first four-way reversing valve 2-1 1-1 suction ends complete not exclusively cooling two-stage compression refrigeration cycle among the second throttle with medium temperature evaporator.

When having, when cryogenic vaporizer needs defrosting in low-pressure stage unit, corresponding low-pressure stage unit is defrosting low-pressure stage list Member, remaining low-pressure stage unit are refrigeration low-pressure stage unit.Two-way valve 8 is closed, and defrost the first four-way described in low-pressure stage unit Reversal valve 2-1 first interfaces are connect with second interface, third interface is connect with the 4th interface, the second four-way reversing valve 2-2 First interface is connect with the 4th interface, second interface and third interface connect.The first four-way changes described in refrigeration low-pressure stage unit It is connected to valve 2-1 with the interface of the second four-way reversing valve 2-2 constant.Above-mentioned in the second throttle of medium temperature evaporator Between on not exclusively cooling two-stage compression refrigeration cycle heating power process basis, defrost cryogenic vaporizer defrosting described in low-pressure stage unit Thermal procession is as follows：Low-pressure stage compressor 1-1 described in low-pressure stage unit defrost through the first four-way reversing valve 2-1 and second Check valve 7-2 is steamed from the larger middle pressure of the exhaust end sucking degree of superheat of the low-pressure stage compressor 1-1 of refrigeration low-pressure stage unit Gas, steam become high pressure superheated vapor after low-pressure stage compressor 1-1 compression boostings and are discharged into the cryogenic vaporizer 6-1 The cryogenic vaporizer 6-1 is heated in middle condensation, generates the defrosting phenomenon of the cryogenic vaporizer 6-1, the high pressure liquid being condensed into Body working medium becomes middle pressure damp steam through the second throttle 4-2 reducing pressure by regulating flow, and damp steam enters through the second four-way reversing valve 2-2 The medium temperature evaporator 6-2 evaporations, that completes to defrost using the high temperature hot gas of low-pressure stage compressor discharge has medium temperature evaporator Second throttle among not exclusively cooling two-stage compression refrigeration cycle.

The low-pressure stage compressor and high pressure stage compressor are screw compressor, rotor compressor, helical-lobe compressor and work Fill in any one of compressor.

The condenser is air-cooled condenser, water-cooled condenser or evaporative condenser.

The cryogenic vaporizer and medium temperature evaporator are air-cooled or solution refrigerating formula.

The intercooler is plate heat exchanger, double pipe heat exchanger or shell and tube exchanger.

The first throttle valve and second throttle are electric expansion valve, heating power expansion valve, capillary or orifice throttle dress It sets.

First check valve, the second check valve, the first four-way reversing valve and the second four-way reversing valve are the prior art.? It can be replaced with two-way valve, hand valve, three-way diverter valve in system.

The above is only a preferred embodiment of the present invention, it is noted that for the common skill of the art For art personnel, various improvements and modifications may be made without departing from the principle of the present invention, these improvements and modifications Also it should be regarded as protection scope of the present invention.

Claims

1. the operation method of not exclusively cooling refrigeration system among a kind of second throttle, which is characterized in that in each low-pressure stage list Medium temperature evaporator and cryogenic vaporizer are set in member, and the medium temperature evaporator freezes for realizing medium temperature, the cryogenic vaporizer For realizing cryogenic refrigeration or defrosting, which includes the following steps：When all low-pressure stage units realize refrigerating function, Middle pressure saturated liquid working medium is flashed to middle pressure saturated vapor by the medium temperature evaporator, realizes medium temperature refrigeration；The low-temperature evaporation Low pressure liquid working medium is flashed to low-pressure steam by device, realizes cryogenic refrigeration；When there is cryogenic vaporizer to need defrosting, pass through valve Switching realizes that the low-pressure stage compressor of defrosting function is converted into high pressure stage compressor operation, realizes the low-pressure stage list of defrosting function Cryogenic compressor in member is absorbed presses through heat steam in the low-pressure stage compressor of low-pressure stage unit for realizing refrigerating function, Or the mixing hot gas from intercooler with the low-pressure stage compressor of realization refrigerating function is absorbed, it is sent into waits removing after compression The cryogenic vaporizer of frost, the condensation heating cryogenic vaporizer, which is realized, to defrost, in the low-pressure stage unit for realizing refrigerating function Cryogenic vaporizer still realizes refrigerating function；It waits after defrosting, realizes the low-pressure stage unit of defrosting function by valve transfer, Realize refrigerating function.

2. not exclusively cooling system among a kind of second throttle using Defrost for realizing operation method described in claim 1 Cooling system, which is characterized in that including high pressure stage compressor group, condenser, first throttle valve, intercooler and multiple low-pressure stages Unit；Each low-pressure stage unit include low-pressure stage compressor, the first four-way reversing valve, second throttle, cryogenic vaporizer, Medium temperature evaporator, the first check valve and the second check valve；The suction end of the low-pressure stage compressor commutates with first four-way 4th interface of valve connects, and the exhaust end of the low-pressure stage compressor is connect with the second interface of first four-way reversing valve, The third interface of first four-way reversing valve respectively with the import of first check valve and the outlet of second check valve The first interface of connection, first four-way reversing valve connects through the first interface of the cryogenic vaporizer and the second throttle It connects；The first interface of the medium temperature evaporator is connected in parallel and is connect with the air inlet of the intercooler, and described second The second interface of throttle valve and the second interface of the medium temperature evaporator with the intercooler go out liquid after being connected in parallel Mouthful connection, the air-breathing of the exporting of first check valve, the import of second check valve and the high pressure stage compressor group End is connect after being connected in parallel with the gas outlet of the intercooler；The high pressure stage compressor group exhaust end is through the condensation Device, first throttle valve are connect with the inlet of the intercooler.

3. not exclusively cooling refrigeration system, feature among the second throttle according to claim 2 using Defrost It is, the high pressure stage compressor group includes one or more high pressure stage compressor, and particular number is run according to the refrigeration system Operating mode determines, when using more high pressure stage compressors, described in the air-breathing interface parallel connection conduct of every high pressure stage compressor The suction end of high pressure stage compressor group, the exhaust port parallel connection of every high pressure stage compressor is as the high pressure stage compressor The exhaust end of group.

4. refrigeration system not exclusively cooling among second throttle according to claim 2 or 3, which is characterized in that described The quantity at least three of low-pressure stage unit.

5. not exclusively cooling system among a kind of second throttle using Defrost for realizing operation method described in claim 1 Cooling system, which is characterized in that including high pressure stage compressor group, condenser, first throttle valve, intercooler and multiple low-pressure stages Unit；Each low-pressure stage unit includes low-pressure stage compressor, the first four-way reversing valve, the second four-way reversing valve, the second section Flow valve, cryogenic vaporizer, medium temperature evaporator, the first check valve and the second check valve；The suction end of the low-pressure stage compressor with 4th interface of first four-way reversing valve connects, the exhaust end of the low-pressure stage compressor and first four-way reversing valve Second interface connection, the third interface of first four-way reversing valve respectively with the import of first check valve and described the The outlet of two check valves connects, and the first interface of first four-way reversing valve throttles through the cryogenic vaporizer and described second The first interface of valve connects, and the second interface of the second throttle is connect with the second interface of second four-way reversing valve； The first interface of the medium temperature evaporator is connect after being connected in parallel with the air inlet of the intercooler, the medium temperature evaporation The second interface of device is connect with the third interface of second four-way reversing valve, the first interface of second four-way reversing valve and 4th interface is connect after being connected in parallel with the liquid outlet of the intercooler；The exporting of first check valve, described The suction end of the import of two check valves and the high pressure stage compressor group goes out after being connected in parallel with the intercooler Gas port connects；The exhaust end of the high pressure stage compressor group is through the condenser, first throttle valve and the intercooler Inlet connects.

6. not exclusively cooling system among a kind of second throttle using Defrost for realizing operation method described in claim 1 Cooling system, which is characterized in that including high pressure stage compressor group, condenser, first throttle valve, intercooler, two-way valve and more A low-pressure stage unit；Each low-pressure stage unit includes low-pressure stage compressor, the first four-way reversing valve, second throttle, low Warm evaporator, medium temperature evaporator, the first check valve and the second check valve；The suction end of the low-pressure stage compressor and described first 4th interface of four-way reversing valve connects, and the exhaust end of the low-pressure stage compressor connects with the second of first four-way reversing valve Mouthful connection, the third interface of first four-way reversing valve respectively with the import of first check valve and second check valve Outlet connection, the first interface of first four-way reversing valve through the cryogenic vaporizer and the second throttle first Interface connects；The first interface of the medium temperature evaporator is connect after being connected in parallel with the air inlet of the intercooler, institute The second interface of the second interface and the medium temperature evaporator of stating second throttle be connected in parallel after with the intercooler Liquid outlet connection, the exporting of first check valve, the import of second check valve and the high pressure stage compressor group Suction end be connected in parallel after connect with the gas outlet of the intercooler by the two-way valve；The hiigh pressure stage compression The exhaust end of unit is connect through the condenser, first throttle valve with the inlet of the intercooler.

7. not exclusively cooling system among a kind of second throttle using Defrost for realizing operation method described in claim 1 Cooling system, which is characterized in that including high pressure stage compressor group, condenser, first throttle valve, intercooler, two-way valve and more A low-pressure stage unit；Each low-pressure stage unit includes low-pressure stage compressor, the first four-way reversing valve, the commutation of the second four-way Valve, second throttle, cryogenic vaporizer, medium temperature evaporator, the first check valve and the second check valve；The low-pressure stage compressor Suction end is connect with the 4th interface of first four-way reversing valve, the exhaust end of the low-pressure stage compressor and the described 1st The second interface connection of logical reversal valve, the third interface import with first check valve respectively of first four-way reversing valve And the outlet connection of second check valve, the first interface of first four-way reversing valve through the cryogenic vaporizer with it is described The first interface of second throttle connects, and the second interface of the second throttle connects with the second of second four-way reversing valve Mouth connection；The first interface of the medium temperature evaporator is connect after being connected in parallel with the air inlet of the intercooler, described The second interface of medium temperature evaporator is connect with the third interface of second four-way reversing valve, and the of second four-way reversing valve One interface and the 4th interface are connect after being connected in parallel with the liquid outlet of the intercooler；First check valve goes out The suction end of mouth, the import of second check valve and the high pressure stage compressor group is logical by described two after being connected in parallel Valve is connect with the gas outlet of the intercooler；The exhaust end of the high pressure stage compressor group is through the condenser, first segment Stream valve is connect with the inlet of the intercooler.