Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60H—ARRANGEMENTS OF HEATING, COOLING, VENTILATING OR OTHER AIR-TREATING DEVICES SPECIALLY ADAPTED FOR PASSENGER OR GOODS SPACES OF VEHICLES
  • B60H1/00—Heating, cooling or ventilating [HVAC] devices
  • B60H1/32—Cooling devices
  • B60H1/3202—Cooling devices using evaporation, i.e. not including a compressor, e.g. involving fuel or water evaporation
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60H—ARRANGEMENTS OF HEATING, COOLING, VENTILATING OR OTHER AIR-TREATING DEVICES SPECIALLY ADAPTED FOR PASSENGER OR GOODS SPACES OF VEHICLES
  • B60H1/00—Heating, cooling or ventilating [HVAC] devices
  • B60H1/00007—Combined heating, ventilating, or cooling devices
  • B60H1/00014—Combined heating, ventilating, or cooling devices for load cargos on load transporting vehicles
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60H—ARRANGEMENTS OF HEATING, COOLING, VENTILATING OR OTHER AIR-TREATING DEVICES SPECIALLY ADAPTED FOR PASSENGER OR GOODS SPACES OF VEHICLES
  • B60H1/00—Heating, cooling or ventilating [HVAC] devices
  • B60H1/0025—Heating, cooling or ventilating [HVAC] devices the devices being independent of the vehicle
  • B60H1/00257—Non-transportable devices, disposed outside the vehicle, e.g. on a parking
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60H—ARRANGEMENTS OF HEATING, COOLING, VENTILATING OR OTHER AIR-TREATING DEVICES SPECIALLY ADAPTED FOR PASSENGER OR GOODS SPACES OF VEHICLES
  • B60H1/00—Heating, cooling or ventilating [HVAC] devices
  • B60H1/32—Cooling devices
  • B60H1/3204—Cooling devices using compression
  • B60H1/3232—Cooling devices using compression particularly adapted for load transporting vehicles
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
  • F25B45/00—Arrangements for charging or discharging refrigerant
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25D—REFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT OTHERWISE PROVIDED FOR
  • F25D11/00—Self-contained movable devices, e.g. domestic refrigerators
  • F25D11/003—Transport containers
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25D—REFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT OTHERWISE PROVIDED FOR
  • F25D3/00—Devices using other cold materials; Devices using cold-storage bodies
  • F25D3/10—Devices using other cold materials; Devices using cold-storage bodies using liquefied gases, e.g. liquid air
  • F25D3/105—Movable containers
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
  • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
  • F17C2223/00—Handled fluid before transfer, i.e. state of fluid when stored in the vessel or before transfer from the vessel
  • F17C2223/01—Handled fluid before transfer, i.e. state of fluid when stored in the vessel or before transfer from the vessel characterised by the phase
  • F17C2223/0146—Two-phase
  • F17C2223/0153—Liquefied gas, e.g. LPG, GPL
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
  • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
  • F17C2225/00—Handled fluid after transfer, i.e. state of fluid after transfer from the vessel
  • F17C2225/01—Handled fluid after transfer, i.e. state of fluid after transfer from the vessel characterised by the phase
  • F17C2225/0146—Two-phase
  • F17C2225/0153—Liquefied gas, e.g. LPG, GPL
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
  • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
  • F17C2265/00—Effects achieved by gas storage or gas handling
  • F17C2265/06—Fluid distribution
  • F17C2265/065—Fluid distribution for refueling vehicle fuel tanks
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F24—HEATING; RANGES; VENTILATING
  • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
  • F24F5/00—Air-conditioning systems or apparatus not covered by F24F1/00 or F24F3/00, e.g. using solar heat or combined with household units such as an oven or water heater
  • F24F5/0007—Air-conditioning systems or apparatus not covered by F24F1/00 or F24F3/00, e.g. using solar heat or combined with household units such as an oven or water heater cooling apparatus specially adapted for use in air-conditioning
  • F24F2005/0039—Air-conditioning systems or apparatus not covered by F24F1/00 or F24F3/00, e.g. using solar heat or combined with household units such as an oven or water heater cooling apparatus specially adapted for use in air-conditioning using a cryogen, e.g. CO2 liquid or N2 liquid
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25D—REFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT OTHERWISE PROVIDED FOR
  • F25D2700/00—Means for sensing or measuring; Sensors therefor
  • F25D2700/12—Sensors measuring the inside temperature

Definitions

• the invention relates to a method for operating a refrigerated vehicle according to the preamble of patent claim 1.
• the invention also relates to a refrigerated vehicle suitable for carrying out the method according to the invention.
• Refrigerated vehicles are equipped with a storage area in which temperature-sensitive goods can be transported at a temperature of e.g. 4°C to 10°C, or as frozen goods at temperatures below 0°C.
• Conventional cooling units are often still used for cooling, but they are increasingly being criticized for their high emissions of noise, CO2, NOx and particulate matter during operation. Cooling using a cryogenic refrigerant is an alternative.
• the cryogenic refrigerant for example liquid nitrogen, is stored in liquid form in a thermally insulated refrigerant tank mounted on the vehicle and, if required, fed to the storage area via a pipeline.
• cryogenic refrigerant is either sprayed into the storage area in liquid or gaseous form (direct cooling) or brought into indirect thermal contact with the atmosphere in the storage area via a heat exchanger arrangement (indirect cooling).
• direct cooling the cryogenic refrigerant is either sprayed into the storage area in liquid or gaseous form
• indirect cooling the cryogenic refrigerant is brought into indirect thermal contact with the atmosphere in the storage area via a heat exchanger arrangement (indirect cooling).
• Examples of such refrigerated vehicles and cooling systems of refrigerated vehicles are described in WO 2011/141287 A1, EP 1 659355 A2, GB 2275098 A or EP 2384916 A2.
• the refrigerant tanks When such refrigerated vehicles are used, the refrigerant tanks must be refilled from time to time in order to replace refrigerant that evaporates or heats up when the goods are cooled.
• Refueling takes place at private filling stations, for example at the location of the logistics company that operates the refrigerated vehicles, or at public filling stations.
• the storage area either continues to be cooled with cryogenic refrigerant from the refrigerant tank, or cooling is suspended for the duration of refueling.
• such filling stations also have two filling lines that have to be connected to the refrigerant tank during filling: A first line is used for supplying liquid cryogenic refrigerant, a second for removing refrigerant vaporized in the refrigerant tank during filling. Since that simultaneous connection of the containers via two lines is very complex and also associated with an increased risk for the operator, more recent developments, such as the subject of WO 2019/042714 A1, allow the connection via only one filling line. With this item, the cryogenic refrigerant is brought into a supercooled state before filling, with the result that the gas phase in the refrigerant tank collapses during the filling process and no longer has to be discharged via a separate line. Before the start of the filling process, only a filling pistol mounted on the filling line has to be connected gas-tight, but detachable, to a corresponding connection piece of the refrigerant tank.
• the invention is therefore based on the object of specifying a method for operating a refrigerated vehicle and a refrigerated vehicle that enables the cold chain to be maintained even over long periods of non-operation, without having to remove products from the refrigerated vehicle.
• the method includes operating a refrigerated vehicle equipped with a storage area for transporting products to be refrigerated by direct or indirect thermal contact with a cryogenic refrigerant a specified cooling temperature is maintained, a first operating state of the refrigerated vehicle, during which the refrigerant for cooling the storage area is taken from a refrigerant tank arranged on the refrigerated vehicle, and a second operating state of the refrigerated vehicle, in which the refrigerant for cooling the storage area is taken from a stationary storage tank, bypassing the refrigerant tank is removed.
• the refrigerated vehicle In the first operating state, also called “transport state” below, the refrigerated vehicle is used as intended for transporting products to be refrigerated and/or delivering them to customers.
• the products to be cooled can be, for example, food products, medical, pharmaceutical, biotechnical or other temperature-sensitive products.
• the refrigerated vehicle can be moved in this operating state, although necessary downtimes - for example during loading and unloading or due to legally prescribed rest periods - are not excluded. However, such periods of downtime are to be dimensioned in such a way that the proper cooling of the storage area by means of refrigerant from the refrigerant tank can be guaranteed during this time.
• the refrigerant tank must be filled up.
• the refrigerant tank is temporarily connected to a stationary filling station, and the refrigerant tank is filled with a defined amount of cryogenic refrigerant. Transporting products to be cooled is not possible during this time, but products to be cooled may still be in the storage area.
• the storage area either continues to be cooled by refrigerant from the refrigerant tank, or there is no cooling, since in many cases the time required for refueling is so short that the temperature can be kept below a specified value during this time without continued cooling .
• the second operating mode also referred to here as "stationary cooling"
• stationary cooling there is a permanent line connection between the refrigerated vehicle and a stationary one storage tank, and the storage area is cooled using cryogenic refrigerant from the storage tank, bypassing the refrigerant tank on the refrigerated vehicle. Similar to refueling, it is not possible to transport products to be cooled in this operating state.
• the storage tank takes over the function of the refrigerant tank.
• the coolant required to cool the storage area is taken from the storage tank and fed to a cooling unit arranged in the storage area via the permanent line connection.
• the amount of refrigerant released from the storage container during the period of stationary cooling depends on the cooling required in the storage area, so it is not - as with refueling - released a fixed predetermined amount of refrigerant to the refrigerated vehicle. Since the stationary storage tank can be chosen to be very large, this operating mode is suitable, for example, for longer operating breaks lasting a few hours to several days, especially for a break in operation at the weekend, or for pre-cooling the refrigerated vehicle to operating temperature before loading. During stationary cooling, the storage area can be kept at the specified temperature, so it is not necessary to move the products to be cooled from the storage area of the refrigerated vehicle to a cold store or similar.
• the refrigerant tank is fluidically decoupled from the storage area. Refrigerant that is still in the refrigerant tank therefore only evaporates at a very low rate, which is determined by the insulation of the refrigerant tank, which means that refrigerant can still be present in the refrigerant tank for days even without prior filling. It is therefore possible in many cases to immediately return to the transport state after the end of the stationary cooling without the cooling of the refrigerant tank to the operating temperature being necessary beforehand.
• the removal of the refrigerant from the stationary storage tank is preferably regulated as a function of a predetermined cooling temperature in the storage area.
• the control is preferably carried out with the same control unit, which is usually present on refrigerated vehicles and which controls the removal of refrigerant from the refrigerant tank in the transport state.
• Liquid nitrogen or pressure-liquefied carbon dioxide are preferably used as cryogenic refrigerants in refrigerated vehicles.
• Cooling of the storage area is always guaranteed during the aforementioned operating states. In a further operating state, not considered in detail here, no cooling of the storage area is provided, for example during an empty run or during maintenance of the refrigerated vehicle.
• a refrigerated vehicle is equipped with a storage area intended for receiving products to be cooled, a refrigeration unit arranged in the storage area for cooling the atmosphere in the storage area through direct or indirect thermal contact with a cryogenic refrigerant, with a refrigerant tank for storing the cryogenic refrigerant, which has a connection piece to connecting a filling gun of a filling station, and equipped with piping connecting the refrigerant tank to the refrigeration unit, wherein the piping, in addition to being connected to the refrigerant tank, is equipped with a connection fitting for connecting to a stationary storage tank for storing cryogenic refrigerant.
• connection on the piping allows the storage area to be cooled with refrigerant from the stationary storage tank, bypassing the refrigerant tank on the refrigerated vehicle, by connecting the piping directly to the storage tank via a line.
• the connection connection is preferably designed as an additional connection that is separate from the connection piece used to fill the refrigerant tank and preferably has a connection mechanism that is suitable for a permanent connection that is not constantly monitored, for example a flange connection.
• the refrigerated vehicle according to the invention therefore enables the "stationary refrigeration" explained above and the maintenance of the refrigeration chain for refrigerated or frozen goods that are in the storage area during longer breaks in operation.
• Means are preferably provided in terms of flow between the connection connection and the refrigerant tank, by means of which the refrigerant tank can be decoupled from the piping, in particular as long as during the stationary cooling there is a flow connection of the piping with the storage tank via the connection port.
• These means are, for example, a valve arranged in terms of flow between the connection connection and the refrigerant tank.
• the refrigerated vehicle preferably has a control device, by means of which the removal of refrigerant from the refrigerant tank or the storage tank can be controlled as a function of a predetermined cooling temperature in the storage area and the decoupling of the refrigerant tank during stationary cooling. While the control device controls the withdrawal of refrigerant from the refrigerant tank when the refrigerated vehicle is being transported, the same control device is preferably used during stationary refrigeration to regulate the withdrawal of refrigerant from the stationary storage tank. An additional control device at the location of the storage tank is therefore not required.
• the refrigerated vehicle is in particular a road vehicle, such as a refrigerated truck or transport vehicle with a semi-trailer (trailer), on whose loading area a storage area for products to be cooled is arranged.
• the invention is suitable, for example, for refrigerated vehicles intended for transporting and/or delivering fresh products (with a storage temperature between +2°C and +12°C) and/or frozen products (with a storage temperature below -18°C).
• FIGS. 1 to 3 schematically show a refrigerated vehicle according to the invention in various operating states.
• the refrigerated vehicle 1 has, in a manner known per se, a storage area 2 equipped with thermally well-insulated walls for accommodating refrigerated goods, in particular for accommodating refrigerated or frozen products for which the cold chain must be maintained.
• a cooling unit in the exemplary embodiment shown here a heat exchanger 3, at which the atmosphere in the storage area 2 is brought into indirect thermal contact with a cryogenic refrigerant, for example liquid nitrogen or liquid carbon dioxide, which is guided through the heat exchanger 3.
• the refrigerant is stored in a refrigerant tank 4 mounted on the refrigerated vehicle 1 and routed to the heat exchanger 3 via piping 5 .
• the refrigerant tank 4 and/or piping 5 are designed to be pressure-resistant and/or thermally well insulated. After passing through the heat exchanger 3 , the refrigerant that evaporates during the heat exchange is discharged via an exhaust pipe 6 without entering the interior of the storage area 2 .
• the supply of cryogenic refrigerant to the heat exchanger 3 is controlled via a control valve 7 which is operatively connected to one arranged in the storage area 2 Temperature sensor 8 stands.
• the refrigerant tank 4 is filled with the refrigerant in the manner described in more detail below via a connecting piece 9 which can be closed flow-tight by a valve 10 .
• the piping 5 is equipped with an additional connection port 11 which can be opened and closed by means of a valve 12 .
• the connection port 11 is used for connection to a stationary storage tank in the manner described below.
• a valve 13 is also provided between the connection connection 11 and the refrigerant tank 4 , which blocks or opens this part of the piping 5 .
• necessary safety fittings such as safety valves in particular, are present, but are not shown here for reasons of clarity.
• the refrigerated vehicle 1 In the operating state ("transport state") shown in FIG. 1, the refrigerated vehicle 1 is mobile and ready for the transport and delivery of products to be refrigerated in the storage area 2 while maintaining the cold chain.
• the valves 10, 12 are closed, the valve 13 is opened, and the refrigerant tank 4 is filled up to a level 14 with a refrigerant, here liquid nitrogen.
• a refrigerant here liquid nitrogen.
• the liquid nitrogen is transported in metered amounts to the heat exchanger 3, where it evaporates in indirect heat exchange with the atmosphere of the storage area 2 and is discharged via the exhaust pipe 6.
• the amount of nitrogen stored in the refrigerant tank 4 is reduced by the ongoing cooling process during the transport of the products to be cooled. If the level 14 in the refrigerant tank 4 falls below a certain minimum level, the driver of the refrigerated vehicle 1 receives a corresponding signal to fill up the refrigerant tank 4.
• the refrigerant tank 4 is filled at a public or private filling station 16 for the cryogenic refrigerant.
• the filling station 16 includes a gas pump 17 with control and monitoring elements 18 and other devices not shown here, such as a subcooler.
• the dispenser 17 is in flow communication via a refrigerant line 19 with a storage tank 20 for the cryogenic refrigerant.
• the dispenser 17 is equipped with a flexible filling line 21 which is suitable for transporting the cryogenic refrigerant in the storage tank 20 and which opens out at a filling pistol 22 .
• the filling gun 22 is adapted to the connection piece 9 of the refrigerant tank 4 and enables a temporary, gas-tight and liquid-tight connection of the filling line 21 to the refrigerant tank 4.
• the filling gun 22 is connected to the connecting piece 9 and the valve 10 is opened.
• the valve 12 remains closed. Cryogenic refrigerant is then filled into the refrigerant tank 4 up to a predetermined fill level.
• the filling process is continuously monitored via the control and monitoring elements 18 and by staff. After completion of the filling process, the valve 10 is closed and the filling gun 22 is disconnected from the connecting piece 9 . The refrigerated vehicle 1 is then available again for the transport and delivery of refrigerated goods.
• the refrigerated vehicle 1 has another operating state available, in which the storage area 2 is cooled directly from a stationary storage tank 24 for the cryogenic refrigerant.
• FIG. 1 In this operating state (“stationary cooling”) shown in FIG.
• the flow connection is established via a preferably flexible, thermally insulated and/or pressure-resistant connecting line 25 which is firmly but detachably connected to the storage tank 25 on the one hand and to the connection port 11 on the other hand.
• valve 12 In this operating state, valve 12 is open and valve 13 is closed; the refrigerant tank 4 is therefore fluidically separated from the piping 5 .
• Refrigerant still present in the refrigerant tank 4 is therefore no longer used to cool the storage area 2, but during this operating state only serves to keep the refrigerant tank 4 at a low temperature.
• the storage area 2 is cooled exclusively by refrigerant from the storage tank 24 , which in this respect takes over the function of the refrigerant tank 4 .
• the temperature in the storage area 2 is also regulated via the control valve 7 and the temperature sensor 8 , the control valve 7 now controlling the inflow of refrigerant from the storage tank 24 in this case.
• the storage tank 24 can be part of a supply system in which a plurality of refrigerated vehicles can be supplied with refrigerant from the storage tank 24 during a break in operation.
• a branch line 26 leads from the connecting line 25, on which a plurality of connecting connections 27, 27', 27" are arranged, which can be connected to a corresponding number of refrigerated vehicles for the supply of cryogenic refrigerant.
• the storage tank 20 of a filling station 16 can also be designed to supply one or more refrigerated vehicles 1 during stationary cooling.
• the storage tank 20 (not shown here) has additional connections for connecting the storage tank 20 with a piping 5 of a refrigerated vehicle 1, similar to the connections 27, 27', 27" of the storage tank 24.
• the refrigerated vehicle 1 is not under the constant supervision of supervisors during the entire operating break, precautions are required to secure the refrigerated vehicle 1 and the fluidic connection to the storage tank 25, which must be determined in each individual case depending on the situation.
• These can include, for example, brake pads 28, which prevent the refrigerated vehicle 1 from rolling away, or a safety valve 29, which automatically prevents the removal of refrigerant from the storage tank 24 in the event of a sudden drop in pressure in the connecting line 25, which indicates a line rupture, or - not shown here - means for remote monitoring which automatically detect the occurrence of an undesired event and send a warning signal to a central control room.
• valve 12 is closed and the connecting line 25 is detached from the connecting port 11 .
• the valve 13 is opened and the storage area 2 is cooled again by the refrigerant still present in the refrigerant tank 4 .
• the refrigerated vehicle 1 is ready for immediate use, possibly after the refrigerant tank 4 has been filled up.
• the cold chain for fresh or frozen products located in the storage area 2 can be maintained even during longer breaks in operation lasting several days without the products having to be relocated from the refrigerated vehicle 1 .

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• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Thermal Sciences (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Devices That Are Associated With Refrigeration Equipment (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=82361292

Family Applications (1)

Country Status (5)

Family Cites Families (8)

• 2021
  • 2021-06-25 DE DE102021003305.1A patent/DE102021003305A1/de active Pending
• 2022
  • 2022-06-24 CA CA3223509A patent/CA3223509A1/en active Pending
  • 2022-06-24 CN CN202280042235.XA patent/CN117480061A/zh active Pending
  • 2022-06-24 EP EP22736256.3A patent/EP4359237A1/de active Pending
  • 2022-06-24 WO PCT/EP2022/067459 patent/WO2022269090A1/de active Application Filing

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