RU2283462C1 - Method for ecologically safe utilization of cold, generated during expansion of natural gas in cryogenic gas expansion machine with diversion of mechanical energy, and system for realization of said method - Google Patents

Abstract

FIELD: power engineering, possible use in devices for using cold of natural gas at outlet of cryogenic gas expansion machine for ecologically safe cooling of air in chambers of refrigerator.

SUBSTANCE: method for utilization of cold, generated during expansion of natural gas in at least one cryogenic gas expansion machine with diversion of mechanical energy includes letting cold gas prior to feeding to consumer through at least one heat exchanger with cooling in this heat exchanger of intermediate fire and explosion safe liquid coolant. Heat exchanger is made with direct contact of substances. Cooling of air in cooling chamber is performed by letting cold liquid coolant through heat exchanger of refrigerator, which is returned to heat exchanger for cooling by natural gas. Draining of liquid coolant is compensated by natural gas by means of feeding liquid coolant into its circulation contour when level of liquid coolant decreases in heat exchanger. System for utilization of cold, generated during expansion of natural gas with diversion of mechanical energy contains at least one cryogenic gas expansion machine with device for receipt of mechanical energy, connected to source of high pressure natural gas, heat exchanger for cooling of liquid coolant, at least one chamber of refrigerator with heat exchanger and accumulating vessel for liquid coolant with device for controlling level of liquid coolant, connected to pipeline, connecting outlet for liquid coolant of heat exchanger for cooling of liquid coolant to at least one heat exchanger of refrigerator chamber. Vessel is made with possible connection to liquid coolant storage and through valve for discharging gas - to atmosphere when a signal is received by valve from device for controlling level of liquid coolant.

EFFECT: improved efficiency, increased ecological safety and explosion safety of cold utilization.

2 cl, 3 dwg

Description

Technical field

The group of inventions relates to the field of power engineering and is intended for use in the means of using cold natural gas at the outlet of the expander for environmentally friendly cooling of air in the chambers of the refrigerator for storing food and other purposes.

The prior art.

In known methods and air cooling systems in refrigerating chambers, environmentally hazardous refrigerants are used, such as freon, ammonia and others. Currently, new less hazardous refrigerants and methods for these purposes have been developed.

One of the solutions to this problem is the use of natural gas as a refrigerant, which is cooled during expansion in the expander with the removal of mechanical energy, for example, to drive an electric generator.

The methods and techniques for generating electricity and “cold” using expanders are covered in a number of publications and patents. For example, in the book “Energy-Saving Turbine Expander Units”, publishing house “Nedra”, 1999, the author - Stepanets A.A., in the article by Aksenov D.T. “Generation of electric energy and“ cold ”without burning fuel”, “Energy Saving” magazine, No. 3, 2003 and other publications, as well as in RF patent No. 2098713, cl. F 16 H 41 / 00.1996 g.

Closest to the proposed method is the use of cold generated during the expansion of natural gas in an expander with the removal of mechanical energy for its implementation according to the patent of the Russian Federation No. 2098713.

In existing solutions, the cooled natural gas in the expander enters the heat exchangers located in the refrigerator chambers (air coolers), where the gas transfers its cold to the air, and then the gas heated in this way enters the gas supply pipeline to consumers.

The problem is that gas is a fire and explosive agent and, when applied, it is necessary to implement a number of organizational and other measures that are governed by the rules and regulations for hazardous facilities. It is rational to use such refrigerators for long-term (strategic) storage of food products, since in this case it is possible to organize personnel trained for working at gas hazardous facilities to serve it. However, a large share of the refrigeration fleet is used for the operational laying and seizing of food products with short shelf life based on the conditions of their market sale. In such cases, individual cameras or groups of cameras are leased to users who need access to the cameras at any time and at any frequency by the personnel they have, i.e. not certified at hazardous facilities. This circumstance posed a technical problem for making the refrigerator safe when using cold natural gas generated during its expansion in expanders. Until now, such a problem has not arisen, and therefore has not been resolved. This is due to the novelty of this direction of the integrated use of energy of excess gas pressure in its preparation and supply to consumers.

SUMMARY OF THE INVENTION

The objective of the invention is the creation of a technical solution that ensures the efficiency, environmental friendliness and fire and explosion safety of the technology for receiving cold generated during the expansion of natural gas in the expanders during the generation of electrical energy and the transmission of this cold to the air of the refrigerator chambers.

Moreover, the method used in this technology should be carried out using well-known processes and equipment of serial production, and the devices used should be improved using standardized elements of this equipment.

The objective of the invention is solved by the fact that the new technology uses an environmentally and fire-, explosion-proof liquid intermediate (between the cold gas after the expanders and the cooled air in the refrigerator chambers) refrigerant, for example, one of the aqueous solutions of polypropylene glycol, ethylene glycol, etc.

The technical result is achieved by the fact that in the method of using the cold generated during the expansion of natural gas in at least one expander, with the removal of mechanical energy by passing the cooled gas before supplying the consumer through at least one heat exchanger with increasing gas temperature and cooling the air in at least one refrigerating chamber according to the invention, while passing the cooled gas through a heat exchanger, cooling is carried out in the intermediate heat exchanger ologicheski fire- and explosion-proof and liquid refrigerant, and the cooling air in the refrigerator compartment is carried out by passing through the cooler heat exchanger cooled liquid refrigerant which is returned back to the heat exchanger for cooling the natural gas it.

In this case, they can use both a heat exchanger for cooling a liquid refrigerant with natural gas, and a heat exchanger for cooling air with a liquid refrigerant with sealed walls separating the medium or with direct contact of the media.

When using heat exchangers for cooling a liquid refrigerant with natural gas and for cooling air with a liquid refrigerant with direct media contact, it is preferable to use a liquid refrigerant that does not react with natural gas at working pressures and temperatures and is not saturated with natural gas.

When using a heat exchanger for cooling a liquid refrigerant with natural gas with direct media contact, it is advisable to compensate for the entrainment of the liquid refrigerant with natural gas by supplying a liquid refrigerant to its circulation circuit when the liquid refrigerant level in the heat exchanger decreases, and to degass the liquid refrigerant by passing it through an expansion tank in front of the inlet to the heat exchanger.

When one or a group of expanders is connected in parallel with a gas reducing station (GDS), the amount of natural gas flow when the refrigerator operating mode is changed is controlled by changing the expander power, if there is one, or by changing the number of expanders working, or by a combination of these methods.

It is advisable to maintain unchanged the pressure of the gas supplied to the consumer by changing the number of included reduction lines on the gas distribution system.

When using more than one refrigerator chambers in the heat exchangers, at least part of them pass the cooled liquid refrigerant sequentially to ensure a different temperature level in the refrigerator chambers and subject to the condition that the temperature at the outlet of the last heat exchanger exceeds the temperature of the cooled natural gas at the outlet of the heat exchanger, in which he cools.

The technical result is also achieved by the fact that the system for using the cold generated during the expansion of natural gas with the removal of mechanical energy, comprising at least one expander with a device for receiving mechanical energy, connected to a source of high-pressure natural gas, and at least , one chamber of the refrigerator with a heat exchanger according to the invention is equipped with a heat exchanger for cooling a liquid refrigerant, the gas inlet of which is connected by a pipe to the outlet of at least one detan EPA yield gas - a gas supply pipe to the consumer, the yield of liquid coolant - with a pump which is connected to the input of at least one heat exchanger of the refrigerator chamber, the output of which is connected to the input conduit for the liquid coolant heat exchanger for cooling the liquid refrigerant.

The heat exchanger for cooling the liquid refrigerant and the heat exchanger of the refrigerator compartment can be either a heat exchanger with hermetically separable media walls, or a heat exchanger with direct media contact.

The system may be equipped with a liquid refrigerant storage tank with a liquid refrigerant level control device connected to a pipeline connecting the liquid refrigerant outlet of the heat exchanger for cooling the liquid refrigerant with at least one heat exchanger of the refrigerator compartment, and configured to connect to the liquid refrigerant storage and through the valve for gas discharge - with the atmosphere upon receipt of a signal from the device for monitoring the level of liquid refrigerant to the valve.

The system can also be equipped with an expansion tank installed at the inlet through the liquid refrigerant of the heat exchanger for cooling the liquid refrigerant and equipped with a device for monitoring the level of liquid refrigerant and a valve for venting gas, configured to connect the expansion tank to the atmosphere upon receipt of a signal from the device for monitoring the liquid level refrigerant

The heat exchanger for cooling liquid refrigerant with direct media contact is made in the form of a housing, in the upper part of which there are spray nozzles for supplying liquid refrigerant, in its lower part there is a bath for collecting chilled liquid refrigerant connected to the pump, means for introducing chilled natural gas are placed above the bath and the upper part of the body has an outlet for heated natural gas and a droplet eliminator installed in front of it to reduce the entrainment of liquid refrigerant.

The heat exchanger of the refrigerator’s chamber with direct media contact is made in the form of a housing, in the upper part of which there are spray nozzles for supplying cooled liquid refrigerant, in its lower part there is a bath for collecting heated liquid refrigerant, connected to the pump, and heated air inlet means connected over the bath with a compressor and a trap of water molecules, and the upper part of the body has an outlet for cooled air and a droplet eliminator installed in front of it to reduce liquid entrainment whom refrigerant.

The system is equipped with pressure and gas temperature sensors installed on the gas supply line to the consumer, and at least one air temperature sensor in the refrigerator chamber associated with the operation matching unit (BSO), one or a group of expanders are connected in parallel with an existing gas reducing station (GDS) ), BSO is made with the possibility of changing the power of the expander or expanders or changing the number of working expanders, as well as changing the number of connected HRS reduction lines when deviating the sizes measured by the specified sensors, from the set values.

At least one air temperature sensor in the refrigerator chamber is connected with controlled shutoff bodies with the possibility of regulating the supply of chilled liquid refrigerant to the heat exchanger of the refrigerator chamber and / or supply of cooled air to the refrigerator chamber when the air temperature in the refrigerator chamber deviates from a predetermined value.

The specified temperature in the refrigerator chambers is maintained and regulated by changing the temperature and the amount of liquid refrigerant that is passed through the air coolers. A change in these indicators for liquid refrigerant causes a change in the operating mode of the heat exchanger, in which it is cooled by gas after the expander. The change in temperature of the gas that is passed through the gas-liquid heat exchanger is controlled by a change in the degree of expansion of the gas in the expander, and the amount of gas that is passed through this heat exchanger is controlled by a shut-off regulating body installed at its inlet using an automation system.

From this it follows that the operating modes of the refrigeration system of the refrigerator and expanders are interconnected and mutually determine the actions of their regulation system. In addition, the operation modes of expanders and GDS are also interconnected and they should automatically change so that the pressure and temperature of the gas in the pipeline supplying it to consumers are maintained within specified limits. For example, when an additional expander is turned on or with an increase in its power, one or more reducing “threads” (reduction lines) should be taken out of operation on the GDS.

During the operation of the energy-refrigerating complex at the gas distribution system, the time-varying operating modes of the gas supply system to the gas distribution system, gas consumption system, refrigeration system of the refrigerator, expander-generator power unit, gas-reducing units of the gas distribution system and an external power supply network to which it transfers electricity should be clearly and interdependently changed.

The property of the claimed system is to unconditionally maintain the parameters of the gas supplied to consumers within the specified limits, regardless of any changes in the gas, refrigeration systems and external power supply, and this property should be provided by self-propelled guns. This problem is solved by the fact that pressure sensors and gas temperatures are installed in the gas supply pipeline, which, when these parameters deviate, form pulses, which are converted into new pulses in the program unit that affect the control system of the expander-generator unit and the control system of the reducing units of the GDS , at the same time the required cold supply of the refrigerator, regardless of changes in the parameters of the gas supplied to the gas distribution station. In addition, the task of the program unit is to perform the operation to select the number and specific numbers of both the expander-generator units and the reducing units of the GDS, which must be entered or taken out of operation. This is due to the fact that, as a rule, some of them are in repair and preventive maintenance.

Brief Description of the Drawings

A group of inventions is represented by drawings, where:

figure 1 is a functional diagram of the claimed system is a gas energy-refrigerating complex (ECC);

figure 2 - functional diagram of the cooling system of the air of the refrigerator chamber with liquid refrigerant;

figure 3 is a functional block diagram of an automatic control system (ACS) of a gas energy refrigerating complex.

Figure 1 presents a diagram of the claimed system is a gas energy refrigerating complex, including a cold supply system that implements the proposed method, showing the relationship of its components with each other and with GDS. As you can see, this complex includes the GDS 100, the power unit 101 with the expander-generator units, the refrigerator 102 and the refrigeration system of the refrigerator chambers. All these objects are connected by one gas stream. Each object that makes up the energy-refrigerating complex produces its own positive effect:

- GDS 100 - regulates the process of gas reduction during joint work with the power unit;

- Power unit 101 generates electricity and cold;

- The refrigerator 102 provides refrigerated storage of food;

- The cold supply system 103 selects the cold from the gas after the expander and transfers it to the air of the refrigerator chambers;

- The automatic control system (ACS) provides coordinated in time operation of technological processes occurring in the facilities of the complex based on the conditions of gas supply to consumers with specified parameters and the required cold supply of the refrigerator.

GDS 100 and power unit 101 are connected in parallel to an external source of high pressure gas and to the gas supply pipeline to consumers. The cold gas after the expanders (when connected in parallel) enters the collector, from which the gas enters the cold supply system, which receives cold from the gas and transfers it to the air in its chambers.

Thus, the system that implements the method is a unit for taking cold from the gas and transferring it to the liquid intermediate refrigerant and an interconnected circulation system with a pumping unit that delivers liquid refrigerant to the heat exchangers (air coolers) of the refrigerator chambers to transfer the brought cold to the air and then carries out return of the liquid refrigerant to the heat exchanger again for taking cold from the gas. This system is shown in FIG. 1 together with the power unit and GDS.

The cold gas extraction unit is arranged as follows: to the gas outlet from the expander or to the collector 1 by a pipe equipped with a shut-off-regulating body 2, a heat exchanger 3 is connected for cooling the liquid refrigerant, the outlet of which is connected by a pipe equipped with a shut-off element 4 to the gas exhaust pipe 5 to consumers with a closed shut-off body 6. The amount of gas that must be passed through the heat exchanger 3 depends on the cold consumption of the refrigerator and is controlled by a controlled shut-off and regulating body 2. With this unit interacts circulating cold supply system of the refrigerator via the heat exchanger 3. In the heat exchanger 3 via conduit equipped with shut-off and the regulator 7 is fed into the heated air coolers liquid intermediate refrigerant. The amount of liquid refrigerant that must be passed through the heat exchanger is controlled by a controlled organ 7. After it is cooled in the heat exchanger 3, it is taken by a pump 9 through a pipe equipped with a shut-off element 8 and fed to the collector 10 of the refrigerator. From the collector 10, the liquid refrigerant through the locking and regulating devices 11 enters the heat exchangers 12 of the chambers 13 of the refrigerator, where it gives off the cold brought from the gas to the air. Then, the liquid refrigerant heated in the heat exchangers 12 is discharged to the collector 14 and then through a pipeline equipped with a shut-off element 15, with the shut-off element 16 closed, it is fed through a controlled shut-off-regulating element 7 again to the heat exchanger 3 for taking cold from the gas. In this case, the temperature difference between the gas and the liquid refrigerant at the inlet and outlet of the heat exchanger 3 is controlled by changing the ratio of the number of media that pass through it.

The required temperature difference between the gas at the inlet to the heat exchanger 3 and the air in the refrigerator chamber 13 is determined by summing the specified temperature differences in the heat exchangers 3 and 12 between the heat transfer media and the temperature head loss in the pipeline connecting them. The absolute value of the temperature of the gas at its inlet to the heat exchanger 3 is determined by summing the predetermined air temperature in the refrigerator chamber 13 with the indicated temperature difference, that is, with the loss of temperature head in the heat exchangers and the pipeline. The required level of this gas temperature is ensured by controlling the degree of expansion of the gas in the expanders. The magnitude of the flow of cold gas supplied to the heat exchanger 3 is controlled by changing the power of the expander (if it is one) or changing the number of expanders included in the work. And the magnitude of the flow of liquid refrigerant supplied to the same heat exchanger 3 is regulated using a controlled shut-off-regulating body 7 based on the conditions of the required cold consumption of the refrigerator 102.

The cold supply system provides for the maximum possible use of the temperature head of the liquid refrigerant. To this end, it is fed first to the first group of heat exchangers 12 to maintain the lowest air temperature in the chambers 13 where they are located. To this end, not all heat exchangers 12 are connected to the collector 10, but only half of them are connected, and the rest are connected to the collector 17 and the collector 14. The liquid refrigerant through the controlled shut-off-regulating bodies 11 in the quantity required by the operating mode of the chamber 13 is supplied to the heat exchangers 12 and having passed them, it enters the collector 14, and then from this collector 14 through the controlled locking and regulating organs 18 (with open locking and regulating bodies 18a) it enters the collector 17 and beyond (with the open locking organ 16 and the closed locking organ 15) enters through the pipeline through the locking-regulating body 7 to the heat exchanger 3. In this case, the locking body 19 on the pipeline connecting the collectors 10 and 17 is closed. Such a piping arrangement for liquid refrigerant allows both the indicated series connection of air cooler groups - heat exchangers 12, and, under certain conditions, their parallel connection in order to supply liquid refrigerant to them at the temperature with which it enters the manifold 10. Temperature level air in the chamber 13 of the refrigerator in the direction of its increase can be controlled by reducing the supply of liquid refrigerant to the air coolers, reducing the number of included air coolers, off speeding one or more fans on the air coolers and reducing their rotation speed.

In heat exchanger 3, cold from gas to liquid refrigerant can be transmitted through a sealed separation wall, as well as by direct contact of heat-exchanging media. In this case, the following requirements are imposed on the properties of a liquid refrigerant: it must be environmentally and fire- and explosion-proof, it must not be saturated with gas, it must be chemically inert to natural gas, and it must retain physical and chemical properties for a long time at operating pressure and temperature. In a system with heat exchangers with dividing walls, a significantly higher temperature head is required for cooling air to a predetermined temperature due to its inevitable losses in these heat exchangers, that is, the created cold is not used efficiently. In the case of transfer of cold by direct contact of heat-exchanging media, the pressure loss is sharply reduced, and the created cold is used with high efficiency.

When using a contact heat exchanger, some entrainment of the liquid refrigerant by the gas stream is inevitable, and during operation it is necessary to recharge the system. For this purpose, it is envisaged to connect the storage tank 20 to the pipeline at the outlet of the liquid refrigerant from the heat exchanger 3 through a controlled shut-off element 21, which is triggered by pulses from the device 22 for controlling the level of liquid refrigerant in the bath of the heat exchanger 3, into which it merges after cooling by irrigation of the oncoming flow cold gas after the expander. The storage tank 20 is connected to the liquid refrigerant storage by a pipe equipped with a shutoff body 23. In addition, this tank 20 is connected to the gas manifold 1 by a pulse tube equipped with a shutoff 24 and to the atmosphere through the shutoff 25.

With direct contact of the gas with a liquid refrigerant, some gas saturation is possible. In this regard, to degass the liquid refrigerant at the inlet to the heat exchanger 3, it is passed through the expansion tank 26. In this tank, the level of liquid refrigerant is maintained by discharging the degassing gas through a controlled shut-off element 27, which is triggered by the receipt of pulses from the device 28 level control.

If the specified pressure of the liquid refrigerant after the pump 9 is exceeded due to a mismatch between its supply and flow rate through the heat exchangers 12, it is transferred to the inlet of the heat exchanger 3 through a pipeline with a valve 29.

The contact heat exchanger 3 (Fig. 2) is a vertical cylindrical vessel - housing 30. In the upper part of the housing 30 there is a gas outlet, in front of which there is a droplet eliminator 31 of a traditional design to prevent gas entrainment of liquid refrigerant, and a device 32 for spraying is installed below the droplet eliminator 31. liquid refrigerant to irrigate an oncoming flow of cold gas, which is introduced through the means 33 in the lower part of the vessel 30. To the device 32 for spraying heated in the chambers 13 of the refrigerator liquid refrigerant is supplied through its inlet through channels. In the lower part of the vessel body 30 there is a bath for collecting liquid refrigerant cooled by contact with the gas, from which it is taken by the pump 9a and then, as previously described, is supplied to the collector 10 of the refrigerator. In this bath, as noted, the level of liquid refrigerant is maintained within predetermined limits. In this case, the gas inlet is located above the level of liquid refrigerant in this bath.

In the invention, as an alternative solution, it is proposed to use a contact method for transferring cold from liquid refrigerant to the air of the refrigerator chambers 13 instead of using traditional type air coolers, that is, heat exchangers with hermetic walls separating heat-exchanging media. At the same time, as in the above-described method of cooling a liquid refrigerant with cold gas, the counter vertical air stream is cooled by irrigation with a cold liquid refrigerant in a similar heat exchanger 12, which is also discharged into a collecting bath, and from it it is pumped through a pipeline returns to the heat exchanger 3 for cooling with cold gas after the expanders.

In FIG. 2 shows a functional diagram of a system for taking air from a refrigerator chamber, cooling it in a contact heat exchanger with liquid refrigerant, and returning cold air back to the refrigerator chamber.

The air from the refrigerator chamber 13 is evacuated through a channel 34 by a compressor 35, in front of which a trap 36 of microcrystals of molecular water, carried with the air stream from the refrigerator chamber 13, is installed. This trap 36 is a device in which there are channels meandering along the air, providing multiple contact of air during its movement with the walls. The walls of these channels have a temperature several degrees below air temperature, which ensures the adhesion of microcrystals of molecular water to them, that is, their capture. This temperature of the walls of the channels can be achieved by cooling them with liquid refrigerant. Further, the “dried” air is thus supplied to the inlet of the contact heat exchanger 37, in which it moves from the bottom up, is irrigated with cold liquid refrigerant and cooled. Cold air through the outlet, in front of which a droplet eliminator 31 is installed, is supplied to the refrigerator chamber 13 through a channel 38 equipped with a controlled regulatory body 39. The circulation of air in the chamber 13 is traditionally provided by fans.

A bath is arranged in the lower part of the heat exchanger housing 37, in which the sprayed liquid refrigerant is collected. Its level in this bath is maintained within specified limits by changing the flow. The air inlet to the contact heat exchanger 37 is located above the specified level. Essentially, this heat exchanger is similar to the heat exchanger described above when considering the cooling of a liquid refrigerant with a cold gas. The liquid refrigerant after heating in contact with air is taken from the bath by the pump 9a and piped into the heat exchanger 3 for gas cooling.

Any combination of these methods of cold exchange between gas and liquid refrigerant can be used in the refrigerator’s cold supply system.

The energy-refrigerating complex consists of several objects united by a single gas stream. Moreover, this complex is connected with gas and external electrical systems, the operating modes of which vary significantly over time (by season, during each month, by week of the month and by hour during the day). To ensure stable and efficient operation of such a complex complex, whose main goal is to maintain the pressure and temperature of the gas supplied to consumers within the specified limits and guaranteed cold supply of the refrigerator, an automatic control system (ACS) is required that is able to influence the determining processes in a coordinated and directed way. and characteristics of the objects combined into a complex.

Figure 3 presents a diagram of an energy-refrigerating complex and its control technology. As noted, the main specific purpose of this system is to clearly maintain the parameters of the gas at the outlet of the energy refrigeration complex. The pressure sensor 40 and the temperature sensor 41 of the gas supplied to the consumer, as well as the air temperature sensor 42 in the refrigerator chamber 13 control these parameters and when they deviate from the permissible limits, they give out their pulses to the operation coordination unit (BSO) 43. In turn, BSO 43 according to the program it converts them into new impulses that act simultaneously on the operation mode of the power unit from the expander-generator units 44 through their automation systems 45 and on the operation mode of the GDS. This unit performs a directional search for the type of impact (turn on / off the expander and simultaneously: turn on / off the “thread” (reduction line) on the GDS), select the number of the expander and the number of “thread” that are in operation or in reserve and then feeds commands for their corresponding operation.

A “thread” connects the high pressure gas collector 46 to the low pressure gas collector 47. It is a pipeline equipped with two reducing valves 48 and 49, one of which is a working one, and the other is a backup. The backup valve 48 is always open. This valve 48 has a diaphragm control head. If gas is supplied under pressure to this head, then valve 48 closes and the thread is turned off. For this purpose, two controlled shut-off bodies 50 and 51 are installed on the head. One (pos. 51) - for supplying compressed gas to the head when the “thread” is turned off, and the other (pos. 50) - for discharging gas from it upon receipt commands for opening the “thread” while closing the shut-off element 50. Gas is supplied to the heads of the reducing valves 48 or 49 from the pressure reducer 52 at the required pressure. Here one of the possible embodiments of the reducing thread is described.

With increasing air temperature in the chamber 13 of the refrigerator from the temperature sensor 42, a pulse simultaneously enters the BSO 43 and the control unit 53 of the refrigeration supply system of the refrigerator. BSO 53 monitors, using a sensor 50, the temperature of the liquid refrigerant at the outlet of the heat exchanger 3, in which it is cooled with cold gas after the expanders 44 entering it through a controlled shut-off-regulating organ 2. This organ 2 changes the gas supply to the heat exchanger 3 by pulse, which fed to it from the BSO 53 after converting the pulse in it from the temperature sensor 50. The BSO 53 may, according to the program, provide impulses to control the shut-off-regulating body 11, which regulates the supply of liquid refrigerant to the heat exchanger 12 and to control the bypass organ 29.

An energy-refrigerating complex with an automation system operates and is regulated as follows.

During the operation of the gas distribution system, gas from an external source enters the manifold 46, and from it through the reducing "threads" it enters under collector pressure 47, which is connected to the gas supply pipe to consumers. Sensors 36 pressure and 37 temperature are installed on this pipeline.

A collector 55, common to all expander-generator units, is connected to the collector 46, from which gas enters the expanders and then exits to the low pressure manifold 1. Next, the gas through an open shut-off-regulating organ 2 enters the heat exchanger 3, in which it cools the liquid intermediate refrigerant. From this heat exchanger 3, gas is piped to a gas supply line 43 to consumers.

Regulation and control of the gas complex according to the deviations of the readings of sensors 36 and 37, as noted, is carried out using pulses from them, which are received in BSO 53, are converted into new pulses and fed into automation systems for controlling the expander-generator units 44 to change the operating modes of the power unit and GDS.

In the heat exchanger 3, through which the cold gas from the collector 1 passes, liquid refrigerant flows in the opposite flow, is cooled and then fed to the heat exchanger 12 of the refrigerator chamber 13. At the outlet of the heat exchanger 3, its temperature is monitored using a sensor 50, and when it deviates from the set value, an impulse is supplied to BSO 53 to change the gas passage through the organ 2 or supply liquid refrigerant through the organ 11.

The air temperature in the chamber 13 of the refrigerator is controlled by the sensor 42. When it deviates from the set value, it gives a pulse to BSO 53, which converts it to new pulses and feeds them to the organ 11 for directional influence on the supply of liquid refrigerant to the heat exchanger 12 or on the regulation of its value organ bypass 29.

The above material allows us to conclude that the proposed technical solution in the scope of two inventions (a method and system for its implementation) overcomes a number of problems that stand in the way of increasing the efficiency of using the cold generated during the generation of electricity by the expander-generator units due to the energy of technological differences in natural gas at the gas distribution station to create highly efficient environmentally friendly refrigerators.

Industrial applicability.

The present invention can be applied in gas distribution systems of industrial housing centers, at compressor stations of main gas pipelines and in gas fields.

Claims (15)

1. The method of using the cold generated during the expansion of natural gas in at least one expander, with the removal of mechanical energy by passing the cooled gas before supplying the consumer through at least one heat exchanger while increasing the temperature of the gas and cooling the air in at least one cooling chamber, characterized in that the heat exchanger is made with direct contact of the media, while passing the cooled gas through the heat exchanger, cooling in this heat exchanger is intermediate about fire and explosion-proof liquid refrigerant, and air cooling in the refrigerator is carried out by passing a cooled liquid refrigerant through the heat exchanger of the refrigerator, which is returned back to the heat exchanger to cool it with natural gas, while compensating for the entrainment of the liquid refrigerant by natural gas by supplying liquid refrigerant to its circulation circuit with a decrease in the level of liquid refrigerant in the heat exchanger. 2. The method according to claim 1, characterized in that a heat exchanger is used to cool the air with liquid refrigerant with sealed media separating walls or with direct contact of the media. 3. The method according to claim 1 or 2, characterized in that they use a liquid refrigerant, which at operating pressures and temperatures does not enter into chemical reactions with natural gas and is not saturated with natural gas. 4. The method according to claim 1 or 2, characterized in that the degassing of the liquid refrigerant is carried out by passing it through an expansion tank before entering the heat exchanger. 5. The method according to claim 1, characterized in that the expander or group of expanders is connected in parallel to the existing gas reducing station (GDS), while the flow of natural gas when changing the operating mode of the refrigerator is controlled by changing the power of the expander, if it is one, or by changing the number working expanders, or by a combination of these methods. 6. The method according to claim 5, characterized in that the pressure of the gas supplied to the consumer is kept constant by changing the number of included reduction lines on the GDS. 7. The method according to claim 1, characterized in that when using more than one refrigerator chambers in heat exchangers, at least part of them pass the cooled liquid refrigerant sequentially to provide a different temperature level in the refrigerator chambers and subject to the condition that the outlet temperature the last heat exchanger exceeds the temperature of the cooled natural gas at the outlet of the heat exchanger. 8. A system for using the cold generated by the expansion of natural gas with the removal of mechanical energy, comprising at least one expander with a device for receiving mechanical energy, connected to a source of high-pressure natural gas, and at least one refrigerator chamber with a heat exchanger, characterized in that it is equipped with a heat exchanger with direct media contact for cooling a liquid refrigerant, the gas inlet of which is connected by a pipeline to the outlet of at least one expander, the gas outlet - with a gas supply line to the consumer, the liquid refrigerant outlet is connected to a pump that is connected to the inlet of at least one heat exchanger of the refrigerator chamber, the outlet of which is connected by a pipeline to the liquid refrigerant inlet of the heat exchanger for cooling the liquid refrigerant, as well as an accumulating tank for liquid refrigerant with a device for monitoring the level of liquid refrigerant connected to the pipeline connecting the outlet through the liquid refrigerant of the heat exchanger for cooling the liquid refrigerant with at least one a heat exchanger of the refrigerator’s chamber, and made with the possibility of connecting to the liquid refrigerant storage and through the valve for gas discharge, to the atmosphere when a signal is received from the device for monitoring the level of liquid refrigerant to the valve. 9. The system of claim 8, characterized in that the refrigerator chamber heat exchanger is a heat exchanger with airtight walls separating the medium. 10. The system of claim 8, wherein the heat exchanger of the refrigerator chamber is a heat exchanger with direct contact media. 11. The system of claim 8, characterized in that it is equipped with an expansion tank installed at the inlet through the liquid refrigerant of the heat exchanger for cooling the liquid refrigerant and equipped with a device for monitoring the level of the liquid refrigerant and a gas vent valve configured to connect the expansion tank to the atmosphere at receipt of a signal from the device for monitoring the level of liquid refrigerant. 12. The system of claim 8, characterized in that the heat exchanger for cooling the liquid refrigerant is made in the form of a housing, in the upper part of which there are spray nozzles for supplying liquid refrigerant, in its lower part there is a bath for collecting the cooled liquid refrigerant connected to the pump, a chilled natural gas input means is placed above the bathtub, and the upper part of the body has an outlet for heated natural gas and a droplet eliminator installed in front of it to reduce the entrainment of liquid refrigerant. 13. The system of claim 10, wherein the refrigerator chamber heat exchanger is made in the form of a housing, in the upper part of which there are spray nozzles for supplying the cooled liquid refrigerant, in its lower part there is a bath for collecting heated liquid refrigerant, connected to the pump, above the bath contains a means of introducing heated air, connected to a compressor and to a trap of water molecules, and in the upper part of the body has an outlet for cooled air and a drip catcher installed in front of it for smart Reducing the entrainment of liquid refrigerant. 14. The system of claim 8, characterized in that it is equipped with pressure and gas temperature sensors installed on the gas supply line to the consumer, and at least one air temperature sensor in the refrigerator chamber associated with the operation coordination unit (BSO), one or a group of expanders connected in parallel to an existing gas reducing station (GDS), BSO is configured to change the power of the expander or expanders or change the number of working expanders, as well as change the number of connected reduction lines GDS Ia rejecting parameter values measured by said sensor from the predetermined values. 15. The system of claim 8, characterized in that at least one air temperature sensor in the refrigerator chamber is connected to controlled shut-off bodies with the ability to control the supply of chilled liquid refrigerant to the heat exchanger of the refrigerator chamber and / or the supply of cooled air to the refrigerator chamber when deviation of air temperature in the refrigerator chamber from the set value.

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