DE3141202A1 - METHOD FOR GENERATING REFRIGERATION IN COMPRESSOR COOLING SYSTEMS - Google Patents

Description

3U1202

Vsesojuzny Nauchno-Issledovatelsky Experimentalno-Kons truktorsky institute Elektroby tovykh Mashin i Priborov . "Kiev, USSR

Process for generating cold in compressor cooling systems

The invention relates to a method for generating cold in cooling systems with compressor cooling units, the application of this process to compression refrigerators "with at least two cold chambers and refrigerants to carry out the procedure.

Generally known is a method for freezing and storing products in domestic refrigerators with a compression refrigeration unit, which is based on the fact that die.Produkte are introduced into one or more refrigeration chambers, the temperature in the freezing chamber, which is used for freezing and permanent storage, during freezing -24 ⁰ C and with the permanent

53Q-P89O25-M-61-SF-Bk

storage ^{must not exceed -18 0} C, and a temperature in the range of 0 to * 5 ⁰ C is maintained in the cooling chamber for short-term storage. Brief storage is understood to mean storage periods of 2 to 7 days and permanent storage storage times of up to 10 months, depending on the type of product.

These temperature conditions are created using known cooling methods.

An energetically particularly favorable process is based on the cold generation with a vapor compression unit in which the refrigerant circulates in a closed circuit. Boiling in the evaporator, ie the refrigerant evaporates at a reduced pressure P and low temperature. The required heat of evaporation is withdrawn from the objects to be cooled, causing their temperature to drop. The vapor formed is sucked off by the compressor, in this compressed to a condensing pressure P 'and fed to the condenser, in which it is cooled with water or air. Since heat is extracted from the steam, condenses this. The liquid refrigerant obtained is passed through a throttle device in which its The temperature and its pressure drop, and then returned to the evaporator for renewed evaporation, which results in a working cycle of the refrigeration unit, is equivalent to.

It is well known that it can be used to increase the economy of operation of compression refrigeration units required is the specific cooling capacity. increase by, for example, the specific Volume cooling capacity of the cooling unit is increased or the compressor's rate of delivery is increased. It is also known that the delivery rate of the compressor reverses the delivery pressure and the suction pressure is directly proportional.

In order to achieve the freezing temperature, that is, temperatures from -24 ⁰ C or less, the vapor compression refrigeration systems with large P- / P ratios, and hence a low delivery efficiency, and thus a low specific refrigerating capacity to be used. .

For the generation of cold, methods are also known in which two-stage and multi-stage refrigeration units are used will; With this method, the refrigerant is not immediately, but gradually, ie in two or several stages with intermediate cooling of the. Partly compressed vapors from the boiling pressure to the condensing pressure condensed.

The ratio of the delivery pressure to the suction pressure of the refrigerant in each stage is smaller than that Ratio of the condensing pressure to the boiling pressure, which are run through cyclically.

In the two-stage or multi-stage compression refrigeration

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aggregates that are used in known processes for cooling, is a closed Coolant circuit, with ammonia and fluorine-containing saturated hydrocarbons as refrigerants, mainly methane and ethane derivatives are used.

The known methods enable the generation of cold at a level of -24. ⁰ C and below. Furthermore, temperatures in the range from 0 ⁰ C to +5 ⁰ C can be generated, which are required for cold storage.

However, the known methods are due to the successive compression of the refrigerant in several stages with intermediate cooling of the partially compressed vapors.

Complicated units are required to carry out these known processes for generating cold required that 'consist of several compressors, chokes, coolers, evaporators and other assemblies exist. In addition, the use of several compressors increases the energy consumption and the Reliability decreased.

For producing refrigeration at a temperature level of 0 ⁰ C to +5 ⁰ C and -18 ⁰ C and below, it is also known to use a separate cooling unit for each temperature range, the cooling units according to the known vapor compression cycle work, mainly as a refrigerant difluoro-

dichloromethane is used.

However, this known procedure leads to a low specific refrigeration capacity at the low temperature level as well as increased energy consumption. This is due to the fact that (-18 ⁰ C and below) a large difference between the boiling point and the condensation point and, consequently, a large value is the ratio of the condensing pressure P ₁ to boiling pressure P required to generate low temperatures. As the ratio of these pressures increases, the degree of delivery and the degree of efficiency of the compressor decrease, as a result of which the specific cooling capacity of the cooling unit decreases and the energy consumption increases.

Finally, methods are also known for generating cold to temperature levels that ensure the cooling, freezing and storage of products with less energy consumption, in which the conventional working cycle of vapor compression cooling units is complicated by additional process steps, namely by accumulating the liquid refrigerant and partial evaporation before throttling as well as through circulation of the -liquid refrigerant in two circuits, each of which has an evaporator for evaporating the refrigerant at the temperature level +5 ⁰ C to ^{0 0} C as well as -18 ⁰ C and below.

Although these procedures reduce energy consumption

slightly reduce, complex cooling units are required for their implementation, which have decreased reliability.

At the same time, an optimal heat exchange can be achieved by using a mixture of different Components of existing refrigerant can be achieved, which increases the efficiency of compression and thus allows an increase in the specific cooling capacity of the cooling unit.

■ As is well known, a high specific cooling capacity can be achieved with mixtures of refrigerants, which each have different boiling points. A special feature of such multi-component refrigerants is in that from the compressed mixture, the higher-boiling component and in the first condensation stage the lower boiling point in the second condensation stage Component condensed. The condensed components expand and boil at different temperature levels, whereby the required cooling and freezing temperatures can be achieved.

The use of binary refrigerants or refrigerants consisting of more than two components allows different To achieve boiling points in the evaporators without any additional devices.

A well-known process for generating cold with a closed circuit single-stage compression cooling unit is based on

that the refrigerant in the form of a mixture of components boiling at different temperature levels in

2 a compressor to a pressure of 1.96 MPa (20 kp / cm) compressed, partially liquefied by condensation of the higher-boiling component and by cooling the Direct flow with the return flow in a regenerative the heat exchanger is completely liquefied, which is liquid state immiscible components mixed in a homogenization zone to form a homogeneous mixture be, the 'homogeneous mixture obtained on a

2.

Pressure of 294 kPa (3 kp / cm) throttled and this mixture by evaporation of the lower boiling component partially evaporated in the corresponding zone of the evaporator and the mixture by evaporation of the higher-boiling component is completely evaporated in the regenerative heat exchanger.

As a low boiling component CO ₂ is used, whose boiling point under normal conditions -79.8 ⁰ C; than higher boiling component, for example, difluorodichloromethane eingesetzt-, -having the standard conditions has a boiling point of -29.8 ⁰ C.

This method allows one to be used for cooling of products as well as for freezing and long-term storage at the temperature required, however has a low specific cooling capacity and significant energy consumption.

Known refrigerants for in a closed Cycle-working vapor compression refrigeration units are Mixtures of different gas components, including ethane

- 1 ^ -

and propane. .

These refrigerants have an inadequate specific volume cooling capacity and, when corresponding cooling units are in operation, lead to compression pressures of 0.8 to 1.4 MPa (8 to
economic efficiency.

2
1.4 MPa (8 to 14 kgf / cm) to an only minor host

Also known are refrigerants for compression cooling units operating in a closed cycle, the difluorodichloromethane and a mixture ... of hydrocarbons, namely ethane in an amount of 20 to 40 VaI .-%, propane in an amount of 10 to 30 vol. ^ -%, ■ Isobutane in an amount of 10 to 30% by volume and n-butane contained in an amount of 10 to 30 vol .-%.

However, such refrigerants are explosive and fire hazardous, which is why their use, for example in household refrigerators, which are subject to high requirements in terms of explosion and fire safety.

The use of such refrigerants also brings benefits ■ serious problems in the series production of refrigerators.

The invention is based on the object of a method for generating cold in compressor cooling systems specify for freezing and storage of products as well as a refrigerant for its implementation, with which the specific cooling capacity in generating the required temperature conditions both on

· '* "" * ^: · 3Η1202

the cooling level as well as the freezing and permanent storage level can be achieved ·.

The problem is solved according to the claims.

The inventive method for generating cold with compression refrigerators is based on the use a refrigerant from a mixture of components boiling at different temperatures, in which the Refrigerant compressed to the operating pressure, partially liquefied until a vapor-liquid mixture is formed, then completely liquefied, cooled, throttled and partially and then completely evaporated will; the method according to the invention is characterized in that the complete liquefaction of the refrigerant before cooling by dissolving those components that are in the vapor phase at the operating pressure • are present in the components liquefied at the operating pressure is made.

The concept of the invention can be used accordingly in numerous areas for generating cold in compressor cooling systems, for example in the food industry, for household purposes and in medicine for cooling and for freezing as well as for short-term storage and permanent storage of any products, for example food and for example biological products and also in numerous other technical areas where it is important to maintain cold at a level of -24 ⁰ C and below.

To completely liquefy the refrigerant

bring about, this is expediently ve at a pressure
seals.

2 Pressure from 0.98 to 1.4 MPa (10 to 14 kp / cm)

When applying the inventive concept, for example on household compression refrigerators, the min-, have at least two cold chambers, one of which is a deep-freeze chamber for freezing and permanent storage of products and the other is a cooling chamber for short-term storage of products, it is cheap according to the invention, the refrigerant for cold generation to partially evaporate in the deep-freeze chamber and completely in the cold-storage chamber to generate cold, wherein the refrigerant is expediently at a pressure of

49 to 294 kPa (0.5 to 3 kp / cm ² ) is throttled.

According to the invention, a refrigerant based on difluorodichloromethane can be used, which also contains at least one component with a boiling point under normal conditions between -55 and -85 ⁰ C, for example CO ₀ or trifluoromonochloromethane or trifluoromonobromomethane, in an amount of 10 to 50 vol .-% , a component with a boiling point under normal conditions between -30 and -55 ⁰ C, for example difluoromonochloromethane or propane, in an amount of 10 to

50 vol. I and at least one component with a boiling point under normal conditions between +16 and -30 ⁰ C, for example difluoromonochloroethane, difluoromonochlorobromomethane or octafluorocyclobutane / in an amount of 10 to 75 Vol »-%, the difluorodichloromethane in an amount of 10 to 50% by volume is used.

The refrigerant according to the invention can also have the following compositions:

Trifluoromonochloromethane 10-50

Difluoromonochloromethane 10-15

Octafluorocyclobutane 20-70

Difluorodichloromethane remainder

Difluorodichloromethane. 10-15

Trifluoromonobromomethane. 10-50

Octafluorocyclobutane 20-70

Difluoromonochloromethane remainder

or · .

voi: -%

. Difluorodichloromethane ₄ '10-15

Trifluoromonochloromethane ■ '10-50

Difluoromonochloroathane 20-70

Difluoromonochloromethane "remainder

Difluorodichloromethane 'iO-15

Trifluoromonochloromethane 10-50

DifluoromQnochlorobromomethane ■ 10-70

Difluoromonochloromethane.: Remainder

■ - '3.U1202

Difluorodichloromethane 10-20

Trifluoromonochloromethane 5-30

Octafluorocyclobutane 20-60

Trifluoromonobromomethane 5-30

Difluoromonochloromethane remainder

CO ₂ 10-45

Difluorodichloromethane 10-35

Difluoromonochloromethane 10-35

Difluoromonochloroethane 25-75.

The application of the method according to the invention for Cold generation under the above conditions and the refrigerant according to the invention which is used to carry it out lead to a significant increase in the specific cooling capacity, the economy and the Reliability of corresponding cooling units.

The invention is illustrated below with the aid of exemplary embodiments explained in more detail with reference to the drawing; show it:

Fig. 1: the operating cycle of a household

Compressor refrigerator in the temperature-entropy diagram

and

Fig. 2: a schematic representation of a

Cooling unit for carrying out the invention Procedure.

The process of freezing and storing products in, for example, household compressor refrigerators consists in that the products are introduced into one or more cooling chambers in which the required temperature conditions are generated.

In the freezer, which is used for freezing and permanent storage, a temperature of -24 ⁰ C or below beam freezing and a temperature of about -18 ⁰ C is maintained during permanent storage. In the cooling chamber for short term storage, a temperature in the range of O is maintained to +5 ⁰ C under all operating conditions of the refrigerator. Such temperature conditions are made possible in that the refrigerant is subjected to the sequence of process steps explained below, which are also explained in FIGS. 1 and 2.

The 'refrigerant is first compressed in a compressor λ_ (Fig. 2) (process I-II in "Fig. 1), then cooled with dissipation of heat g. Into the environment (process II-III) and then in a condenser 2 ^ partially condensed until a vapor-liquid mixture is formed. The non-condensed components "of the refrigerant dissolve in the condensed components (process III-IV) with the dissipation of heat q ₂ . The refrigerant is then fed to an evaporator heat exchanger 3_ ", in which it is cooled to a temperature T (process IV-V); the refrigerant is then throttled in a throttle _4 while the temperature is reduced from Ty to T (process V -VI) and then an 'evaporator -5_ of the freezer compartment with dissipation of the heat -q_

supplied from this chamber (process VI-VII), the refrigerant being heated and only partly evaporated 'and thus partly' as vapor and 'partly as liquid'. The refrigerant, which is partly in the vapor state and partly in the liquid state, then passes into the evaporator heat exchanger 3 ^, in which it evaporates completely, with the heat q. from the cooling chamber for the short-term storage of products and removes the heat q ^ from the compressed refrigerant entering the heat exchanger 3 ^ from the condenser 2_. ■

The refrigerant finally reaches the new one Compression in the compressor JU

The ratio P ₁ ZP _{9 of} the pressure of the compressed refrigerant (hereinafter referred to as refrigerant for short) and the relaxed refrigerant (compression ratio) is significantly lower than in the known processes. For example, the compression ratio in the compressor of refrigeration units based on the usual procedure for freezing and storage when using Freon-12 as a refrigerant reaches the value 14. The optimal value of the compression ratio according to the method according to the invention is 3 to 5 The reduction in the compression ratio leads to an increase in the delivery rate of the compressor, which corresponds to the ratio of the real hourly delivery rate of the compressor to the ideal hourly volume produced by the piston. Lowering the compression ratio from 14 to 4 results in a

- 20 -

two to three times the efficiency of the compressor and consequently a significant increase the efficiency of the cooling unit.

This in turn can reduce the energy required for freezing and storing products will. ■

The refrigerant is used for complete liquefaction to a pressure of 0.98 to 1.37 MPa (10 to

2 '

14 kp / cm) compacted. Sufficient for complete evaporation it, the coolant to a pressure of 49 to

2
294 kPa (0.5 to 3 kp / cm) to be throttled.

When the refrigerant is at a pressure below

0.98 MPa (10 kp / cm ² ) or above 1.37 MPa (14 kp / cm ² )

2 compressed, and to a pressure below 49 kPa (0.5 kp / cm)

2
or above 294 kPa (3 kp / cm), the desired increase in the specific cooling capacity of the cooling unit cannot be achieved due to the liquefaction of the refrigerant and its evaporation.

The following examples explain the implementation of the process according to the invention.

The refrigerant in vapor and liquid state is compressed in the compressor ] _ to a pressure of 0.98 to 1.37 MPa (10 to 14 kp / cm ² ) and fed to a condenser 2_. The refrigerant is cooled in the condenser _2 by releasing heat to the environment (air or water). As a result of

t » (· C

■ '3ΗΊ202

Heat removal from the vapors of the refrigerant condense its higher boiling components, which means that the refrigerant partly up to the formation of a vapor-liquid mixture while maintaining the increased Pressure is liquefied. "'■

At this pressure and a temperature of 20 to 45 ^° C., the refrigerant is completely liquefied in the liquefied components through the dissolution of those components which boil lower and are in a vaporous state under these conditions.

The liquefied refrigerant is in the heat exchanger 3_ with the vapor-liquid emulsion formed by the partial evaporation of the refrigerant in the evaporator cooled, which is fed to the heat exchanger in the return flow.

The cooled refrigerant is then passed through a throttle _4_, in which the pressure and the temperature are lowered are fed to the evaporator! 5. When throttling, the pressure of the refrigerant is increased to 49 to 294 kPa

2
(0.5 to 3 kgf / cm) lowered.

5_ in the evaporator boils (evaporates), the refrigerant, the required evaporation heat is extracted from the cooled objects whose temperature thereby drops to -30 ⁰ C. This leads to partial evaporation, in which the majority of the lower-boiling components evaporate. After the exit of the vapor-liquid emulsion from the evaporator 5 ceases

the evaporation of the lower boiling components and the higher boiling components of the refrigerant begin to evaporate. The process of complete evaporation of the refrigerant is carried out in the heat exchanger 3_ in that the heat required to boil the refrigerant is withdrawn from the direct flow by heat exchange between the direct flow and the return flow.

The formed vapors of the refrigerant are carried through. the compressor _1_ is sucked out ^for renewed compression, whereby the operating cycle of the unit is closed.

It is particularly beneficial to increase the delivery pressure

1.18 MPa (1.2 kp / cm ² ) and the suction pressure to 294 kPa

2
(3 kp / cm ·). "

By dissolving the non-liquefied components of the refrigerant in its liquefied components "in the implementation of the refrigeration cycle In single-stage compressor cooling units, complete liquefaction of the refrigerant can occur in one lower condensation pressure and consequently also at a lower delivery pressure can be achieved. Through this it becomes possible to reduce the ratio of delivery pressure to suction pressure, which is the specific The refrigeration capacity of the unit is increased and the efficiency of the compressor is increased by corresponding Reduction of the energy losses in it increases.

To carry out the method according to the invention

■ ■ · 3HI

the refrigerant must be chosen in such a way that it aiming the required temperatures at the corresponding temperature level with a lowered optimum Degree of compaction allowed.

To achieve this goal, "contains the refrigerant difluorodichloromethane with a" boiling point under normal conditions of -29.8 ⁰ C as well as components'

having a boiling point under normal conditions from -55 to -85 ⁰ C, a component having a boiling point under normal conditions of -30 to -55 ⁰ C and components having a boiling point at normal conditions · between +16 and.-30 ⁰ C.

As such components, any known compounds are suitable, for example, CO _2, and Trifluormonochlormethan Trifluormonobrommethan having a boiling point under normal conditions (Normalsublimationspunkt) of -79.8, -81 or -57.75 ⁰ C, Difluormonochlor-. methane and propane with a boiling point under normal conditions of -40.8 and -40 ⁰ C, difluoromonochloroethane, difluoromonochlorobromomethane and octaf luorcy.clobutane with a boiling point under normal conditions of -9.25, -3.4 and -5.8 ⁰ C.

The least effort and consequently the greatest effect can be can be achieved using refrigerants with the following composition:

1. difluorodichloromethane, trifluoromonochloromethane, Difluoromonochloromethane and difluoromonochloroethane;

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2. CO «, difluorodichloromethane, difluoromonochloromethane and difluoromonochloroethane;

3. trifluoromonochloromethane, difluoromonochloromethane, Octafluorocyclobutane and difluorodichloromethane;

4. difluorodichloromethane, trifluoromonochloromethane, Difluoromonochloroethane and difluoromonochloromethane ;

5. difluorodichloromethane, trifluoromonochloromethane, Difluoromonochlorobromomethane and difluoromonochloromethane; ·

6. difluorodichloromethane, trifluoromonochloromethane, Octafluorocyclobutane trifluoromonobromomethane and difluoromonochloromethane.

Any other changes can also be made within the scope of the concept of the invention possible combinations can be used.

The components are to be used in the following proportions:

Trifluoromonochloromethane 10-50

Difluoromonochloromethane 10-15

Octafluorocyclobutane. 20-70

Difluorodichloromethane remainder

Difluorodichloromethane · .. '10 -15

Trifluoromonobromomethane 10-50

Octafluorocyclobutane 20-70

Difluoromonochloromethane "remainder

Difluorodichloromethane Trifluoromonochloromethane Difluoromonochloroethane Difluoromonochloromethane

Difluorodichloromethane Trifluoromonochloromethane Octafluorocyclobutane Trifluoromonobromomethane Difluoromonochloromethane

CO ■
2

Difluorodichloromethane

Difluoromonochloromethane Difluoromonochloroethane

Vol. TO - 10 - 20 - .r% - 15 - 50 - 70 rest

Vol%

10-20 5-30

20 - 60 • 5-30

rest

VoI -.-%

10 - 10 -

10 -25 -

If the low-boiling components in smaller amounts and the high-boiling components in larger, ·. Are used specified quantities as above, the required temperature conditions can not be achieved in the chambers of the refrigerator, which means that the temperature drops in the cooling chamber for short term storage to below 0 ° C, while in the deep-freezing chamber the temperature -18 ⁰ C not is achieved.

On the other hand, when the low-boiling components

are used in larger amounts and the high-boiling components in smaller amounts, the low-boiling components do not dissolve completely in the high-boiling components, which in turn has the consequence that the required temperature conditions cannot be achieved in the cooling chamber, ie the temperature in this Chamber rises to values above +5 ^{0 C.}

Every refrigerant is a mixture of components that are stored in balloons or similar containers. To produce the mixture, such an amount of the liquid component is allowed to flow from each container into a common collecting container, the volume of which corresponds to the predetermined volume percentage of this component in the mixture. Here, first, that component is placed in the sump _r having the lowest vapor pressure of the liquefied gases, namely octafluorocyclobutane, Difluormonochloräthan, Difluomonochlorbrommethan and difluorodichloromethane, whereupon the gases with higher vapor pressure in the liquefied state ie, be added difluoromonochloromethane, Trifluormonobrommethan and Trifluormonochlormethan.

The following are examples of possible variants of the combination of the components for the production of the invention Refrigerant specified.

Example 1

Difluorodichloromethane, CO ₂ , difluoromonochloromethane and difluoromonochloroethane become a refrigerant

- ^: '- *. ■ '''■ . 3U120Z

mixed with the following composition:

Difluorodichloromethane ■ 20

CO ₂ . . ■ 14

Difluoromonochloromethane 20

Difluoromonochloroethane 46.

When used in domestic compressor refrigerators, this refrigerant allows a degree of compression of 4 to 5 and creates the required temperature conditions in the cooling chambers, namely a temperature of 0 to +5 ° C in the cooling chamber for short-term storage and a temperature of. not higher than -24 ⁰ C for freezing and -18 ⁰ C for permanent storage.

Example 2

In a container are difluorodichloromethane, trifluoromonochloromethane, difluoromonochloromethane and Octafluorocyclobutane to form a refrigerant with the following composition mixed:

Difluorodichloromethane 22

Trifluoromonochloromethane 10

Trifluoromonobromomethane 22

Difluoromonochloromethane. 22nd

Octafluorocyclobutane. 24.

This refrigerant allowed-a degree of compaction of the compressor of 4 to 5 and maintain the following temperature conditions: in the cooling chamber from 0 to +5 ° C and in .the deep-freezing chamber is not higher than -24 ⁰ C to freeze and -18 ⁰ C for the duration of storage.

Example 3

In a container, difluorodichloromethah, Trifluoromonochloromethane, difluoromonochloromethane and Difluoromonochloroethane mixed to form a refrigerant with the following composition:

Difluorodichloromethane 25

Trifluoromonochloromethane '20

'. Difluoromonochloromethane. 25 ■ ·

Difluoromonochloroethane 20.

Example 4 "·.

A refrigerant of the following composition is produced using the above process:

Difluorodichloromethane 10

Trifluoromonochloromethane 15

-Difluoromonochloromethane 25

Dif luormonochloroethane .50.

Example 5 · '"·

A refrigerant of the following composition is produced using the above process:

VoI -.-%

Difluorodichloromethane 20

Trifluoromonochloromethane 20 '

Difluoromonochloromethane 10

Difluoromonochloroethane 50.

Example 6 '... ·

A refrigerant of the following composition is produced using the above process:

Vol.-'- έ

Difluorodichloromethane '20 Trifluoromonochloromethane 15

Difluoromonochloromethane. 25th

Difluoromonochloroethane 40.

The refrigerants given in Examples 3 to 6 ensure a degree of compression of 4 to and the generation of the temperature conditions listed above in the corresponding cold chambers of compressor refrigerators. . ■

The required temperature conditions can also be achieved by the following additional refrigerants will:

Example 7

VoI.-

Difluorodichloromethane - 15 Trifluoromonobromomethane ■ 50 Octafluoxcyclobutane 20

Difluoromonochloromethane "15

Example 8

VoI.-

Difluorodichloromethane. 15th . Trifluoromonobromomethane 30

Octafluorocyclobutane · 40 difluoromonochloromethane. '15.

Example 9

VoI.-

Difluorodichloromethane 10

Trifluoromonobromomethane 10

Octafluorocyclobutane 70

Difluoromonochloromethane '10

Example 10

VoI.-

Difluorodichloromethane 15

Trifluoromonochloromethane 50

Difluoropnochloroethane 20

Difluoromonochloromethane -T 5.

Example 11

Difluorodichloromethane Trifluoromonochloromethane Difluoromonochloroethane Difluoromonochloromethane

Vol. 15 ■ 20 50 15.

Example 12

Difluorodichloromethane Trifluoromonochloromethane Difluoromonochloroethane Difluoromonochloromethane

10 10 70 10

Example 13

Difluorodichloromethane Trifluoromonochloromethane Difluoromonochlorobromomethane Difluoromonochloromethane

Vol.

. 15- ■ 50

20th

15th

Example 14

Difluorodichloromethane Trifluoromonochloromethane Difluoromonochlorobromomethane Difluoromonochloromethane

Example 15

Difluorodichloromethane Trifluoromonochloromethane Difluoromonochlorobromomethane Difluoromonochloromethane

18 20

⁴⁴ 18

10 10 70 10

Example 16 Example 17

Difluorodichloromethane ■ 15

Octafluorocyclobutane -60

Difluoromonochloromethane 15

Trifluoromonochloromethane 5

Trifluoromonobromomethane 5 »

Difluorodichloromethane 29

Octafluorocyclobutane 36

Difluoromonochloromethane. 11

Trifluoromonochloromethane 12

Trifluoromonobromomethane ■ 12

Example .1 8

Difluorodichloromethane 10

Octafluorocyclobutane ■ ■. 20th

Difluoromonochloromethane ■ 10

Trifluoromonochloromethane 30 '

Trifluoromonobromomethane 30.

Experimental studies have shown that. the maximum specific cooling capacity of cooling units operated with the refrigerants according to the invention is significantly higher than when using conventional refrigerants. · '. '

In addition, a lowering of the cooling temperature can be achieved by increasing the percentage of components in the

are mixed achieved whose boiling point at · Atmo.sphärendruck below -50 ⁰ C, but the specific cooling capacity of the cooling unit then decreased slightly.

The specific refrigerating capacity of the refrigerator rises with the increase of the percentage of components in a mixture whose boiling point at atmospheric pressure above -10 ⁰ C, to significantly. Here, however, the cooling temperature decreases, which can even come close to the boiling point of the highest-boiling component.

JV

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Claims (1)

Expectations Procedure for. Cold generation with compression cooling units using a refrigerant from a mixture of components that boil at different temperatures by. Compression of the refrigerant to the operating pressure, partial liquefaction up to the formation of a vapor-liquid mixture, complete liquefaction, cooling> Throttling, partial and complete evaporation of the refrigerant, through this marked that the complete liquefaction of the refrigerant before its cooling by dissolving those components that are present in the vapor phase at the operating pressure in the components liquefied at operating pressure is taken. 2. The method according to claim 1, characterized in that the refrigerant to a pressure of 0.98 to 1.37 MPa (10 to 14 kgf / cm) is compressed. 53O-P89Ο25-Μ-6Ί-SF-Bk 3. The method according to claim 1 or 2 for refrigeration in • Compression refrigerators with at least two cold chambers, one of which is a freezer chamber for freezing and for permanent storage of products and the other a cooling chamber for short-term storage of products is characterized in that the refrigerant is used to generate cold in the deep-freeze chamber is partially and completely evaporated in the cooling chamber. 4. The method according to claim 3, characterized in that for partial and then for complete evaporation . the refrigerant to a pressure of. 49 to 294 kPa (0.5 2
up to 3 kp / cm) is throttled. 5. The method according to any one of claims 1 to 4, characterized in that a refrigerant based on difluorodichloromethane is used which has at least one component with a boiling point under normal conditions between -55 and -85 ⁰ C, a component with a boiling point under normal conditions between -30 and -55 ⁰ C and at least one component with a boiling point under normal conditions between + 16 'and -30 ⁰ C. 6. Application of the method according to one of claims 1 to 5 on the generation of cold in household refrigerators. 7. refrigerant for performing the method according to any one of claims 1 to 6, characterized by the following Composition:.' "· 3U1202 *: Γ: Difluorodichloromethane 10 - 50 at least one component with a boiling point under normal conditions between -55 and . -85 ⁰ C 10-50 a component with a boiling point under normal conditions between -30 and -55 ⁰ C 10-50 and at least one component with a boiling point under normal conditions between +16 and -30 ⁰ C 10-75. 8. Refrigerant according to claim 7, characterized in that with a boiling point
it as a component / under normal conditions between -55 and -85 ⁰ C CO ₂ or trifluoromonochloromethane or trifluoromonobromomethane, as a component with a boiling point ^: under normal conditions between -30 and -55 ⁰ C difluoromono- ^ chloromethane, propane and as a component with a boiling point at Normal conditions between +16 and -30 ⁰ C contains difluoromonochloroethane, difluoromonochlorobromomethane and octafluorocyclobutane. 9. Refrigerant according to claim 7 or 8, characterized by the following composition: Trifluoromonochloromethane 10-50 Difluoromonochloromethane 10-15 Octafluorocyclobutane 20 - Difluorodichloromethane rest. 10. Refrigerant according to claim 7 or 8, characterized by the following composition: Difluorodichloromethane 10-15 Trifluoromonobromomethane 10-50 Octafluorocyclobutane 20-70 Difluoromonochloromethane remainder. 11. Refrigerant according to claim 7 or 8, characterized by '' the following composition: Difluorodichloromethane 10-15 Trifluoromonochloromethane 10-50 Dif luormonochloroethane 20 * - - 70 'Difluoromonochloromethane remainder. 12. Refrigerant according to claim 7 or 8, characterized by the following composition: Difluorodichloromethane 10-15 Trifluoromonochloromethane 10-50 Difluoromonochlorobromomethane 10-70 . · Dif luormoikich'lorme than rest. • 13. Refrigerant according to claim 7 or 8, characterized by the following composition: Difluorodichloromethane 10-20 Trifluoromonochloromethane 5-30 Octafluorocyclobutane 20-60 Trifluoromonobromomethane 5-30 Difluoromonochloromethane remainder. 14. Refrigerant according to claim 7 or 8 ,, characterized .by the following composition: VoI, -% CO ₂ · .10-45 Difluorodichloromethane 10-35 • Difluoromonochloromethane 10-35 Difluoromonochloroethane 25 - 15. Refrigerant according to claim 16, characterized by the following Composition: CO ₂ 14 Difluorodichloromethane 20 Difluoromonochloroethane ·. 46 Difluoromonochloromethane .20. 16. Refrigerant according to claim 7 or 8, characterized by the following composition: Trifluoromonochloromethane 10 Trifluoromonobromomethane 22 Difluoromonochloromethane ■ 22 Difluorodichloromethane 22 Octaf luorcyclobutane · ■ 24. 17. Refrigerant according to claim 11, characterized by fol The following composition: ■ Vol .-% Trifluoromonochloromethane. 20th Difluoromonochloromethane 25 Difluorodichloromethane 15 Difluoromonochloroethane 40.