EP4051971A1 - Improved heat pump - Google Patents
Improved heat pumpInfo
- Publication number
- EP4051971A1 EP4051971A1 EP20882090.2A EP20882090A EP4051971A1 EP 4051971 A1 EP4051971 A1 EP 4051971A1 EP 20882090 A EP20882090 A EP 20882090A EP 4051971 A1 EP4051971 A1 EP 4051971A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- conduit
- heat pump
- outlet
- refrigerant
- compressor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000003507 refrigerant Substances 0.000 claims abstract description 34
- 238000000034 method Methods 0.000 claims abstract description 14
- 230000008569 process Effects 0.000 claims abstract description 14
- 238000011144 upstream manufacturing Methods 0.000 claims abstract description 6
- 230000001747 exhibiting effect Effects 0.000 claims abstract 3
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 claims description 44
- 238000001035 drying Methods 0.000 claims description 35
- 229910002092 carbon dioxide Inorganic materials 0.000 claims description 22
- 239000007788 liquid Substances 0.000 claims description 20
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 12
- 239000000203 mixture Substances 0.000 claims description 11
- 239000007787 solid Substances 0.000 claims description 5
- 239000008247 solid mixture Substances 0.000 claims description 5
- 239000001569 carbon dioxide Substances 0.000 claims description 3
- 239000007791 liquid phase Substances 0.000 abstract description 3
- 239000007789 gas Substances 0.000 abstract 3
- 239000007792 gaseous phase Substances 0.000 abstract 2
- 239000003570 air Substances 0.000 description 28
- 238000010586 diagram Methods 0.000 description 19
- 238000001816 cooling Methods 0.000 description 14
- 230000000694 effects Effects 0.000 description 14
- 238000010438 heat treatment Methods 0.000 description 10
- 239000000047 product Substances 0.000 description 9
- 238000001704 evaporation Methods 0.000 description 7
- 239000012530 fluid Substances 0.000 description 6
- 239000000463 material Substances 0.000 description 5
- 238000009835 boiling Methods 0.000 description 4
- 229920006395 saturated elastomer Polymers 0.000 description 4
- 239000000498 cooling water Substances 0.000 description 3
- 238000000605 extraction Methods 0.000 description 3
- 239000012071 phase Substances 0.000 description 3
- 239000011343 solid material Substances 0.000 description 3
- 239000002699 waste material Substances 0.000 description 3
- 239000012080 ambient air Substances 0.000 description 2
- 239000006227 byproduct Substances 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 238000011084 recovery Methods 0.000 description 2
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 238000009360 aquaculture Methods 0.000 description 1
- 244000144974 aquaculture Species 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 238000012790 confirmation Methods 0.000 description 1
- 239000002826 coolant Substances 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000012467 final product Substances 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 235000013305 food Nutrition 0.000 description 1
- 239000008187 granular material Substances 0.000 description 1
- 239000008236 heating water Substances 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000009972 noncorrosive effect Effects 0.000 description 1
- 231100000252 nontoxic Toxicity 0.000 description 1
- 230000003000 nontoxic effect Effects 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000005057 refrigeration Methods 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- 239000010802 sludge Substances 0.000 description 1
- 239000004458 spent grain Substances 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- 230000032258 transport Effects 0.000 description 1
- 239000012808 vapor phase Substances 0.000 description 1
- 238000010792 warming Methods 0.000 description 1
Classifications
-
- 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
- F25B30/00—Heat pumps
- F25B30/06—Heat pumps characterised by the source of low potential heat
-
- 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
- F25B25/00—Machines, plants or systems, using a combination of modes of operation covered by two or more of the groups F25B1/00 - F25B23/00
- F25B25/005—Machines, plants or systems, using a combination of modes of operation covered by two or more of the groups F25B1/00 - F25B23/00 using primary and secondary systems
-
- 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
- F25B41/00—Fluid-circulation arrangements
-
- 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
- F25B40/00—Subcoolers, desuperheaters or superheaters
-
- 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
- F25B9/00—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point
- F25B9/002—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point characterised by the refrigerant
- F25B9/008—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point characterised by the refrigerant the refrigerant being carbon dioxide
Definitions
- the present invention relates to an improved heat pump for drying solid materials and liquid-solid mixtures.
- the present invention relates to a heat pump for drying solid materials, in particular transformation and recovery of waste from fisheries, aquaculture and disposed foods as well as sludge, biodegradables and by-products.
- Solid and semi-solids materials can be pre-formed in suitable shapes for drying such as particulates, granulates or agglomerates to be properly dried.
- the dryer processes Newtonian or non-Newtonian fluid-solid mixtures as they can be blended, cut, granulated or agglomerated prior to drying.
- this invention applies to industrial drying of distiller's byproducts and residues such as wet distillers wet spent grains.
- WO 2019/143254 discloses a modular system and a process of drying solids and liquid-solid mixtures, assigned to the same applicant as the present one.
- the dryer described there can be operated continuously, water is used as cooling medium in the condenser for extracting liquid from the vapor phase discharged from the dryer.
- the condenser requires a large volumetric rate of water to operate satisfactorily, which requires sufficient infrastructure to supply, and discharge water, which again results in loss of energy from the system in discharged water, and possibly cost per unit of water supplied.
- An object of the present invention is to provide an improved heat pump, arranged for use with dryers of solid material described above, with enhanced energy efficiency.
- the present invention concerns an improved heat pump for use with dryers in general, using carbon dioxide as refrigerant.
- the heat pump according to the invention is described in connection with the dryer disclosed in WO 2019/143254 discussed above.
- the improved heat pump is not limited to that particular dryer, and can be integrated with any dryer in need of cooling and/or heating.
- Fig. 1 is a schematic flow diagram illustrating an example of a prior art drying process
- Fig. 2A is a schematic flow diagram showing a first embodiment of the heat pump in accordance with the present invention integrated with the drying process of Fig. 1,
- Fig. 2B is a diagram similar to Fig. 2A, but of a second embodiment of the heat pump in accordance with the invention
- Fig. 3A is a pressure-enthalpy diagram showing the course through the first embodiment of the heat pump of Fig. 2A,
- Fig. 3B is a pressure-enthalpy diagram showing the course through the second embodiment of the heat pump of Fig. 2B
- Fig. 4 is a diagram showing specific cooling effect versus pressure
- Fig. 5 is a diagram showing specific heating effect versus pressure
- Fig. 6 is a diagram showing discharge temperature versus pressure
- Fig. 7 is a diagram showing cooling coefficient of performance versus pressure
- Fig. 8 is a diagram showing heating coefficient of performance versus pressure
- Fig. 9 is a diagram showing combined coefficient of performance versus pressure
- Fig. 10 is a diagram showing actual work input versus pressure
- Fig. 11 is a diagram showing compressor volumetric flowrate versus pressure. Detailed description
- instrumentation such as temperature gauges, pressure gauges, humidity gauges, flow meters and controller have been omitted for the case of simplicity.
- instrumentation such as temperature gauges, pressure gauges, humidity gauges, flow meters and controller have been omitted for the case of simplicity.
- the person skilled in the art would be in a position of including the instrumentation and controllers necessary to operate the process.
- FIG. 1 a simplified flow sheet a first embodiment of a dryer from the prior art disclosed in the above mentioned WO 2019/143254 is shown.
- a dryer chamber housing is indicated by reference numeral 100, having an inlet 101 for waste material with a hopper which feeds a screw conveyor 112 that is time- and flow-controlled to operate in semi-continuous or continuous mode.
- a feeder hopper 500 is arranged upstream of the drier chamber housing inlet 101, having an inlet 501, an outlet 502 in flow communication with the dryer housing inlet 101.
- the feeder hopper is kept in motion by an oscillator 503 to provide an initial de-clogging of the wet material to be dried.
- the feeder hopper 500 is illustrated as an elongate rectangular conduit, inclined in a direction downward in flow direction toward the outlet 502, and with an oscillator means arranged at the inlet end 501 to oscillate the feeder hopper 500 up and down urging the wet material toward the outlet 502 and de-bridging possibly agglomerated feed.
- a rotary impeller 102 is arranged at the bottom of the drying chamber housing 100, which serves to disaggregate and circulate the waste material and, in combination with air flow, establishing a fluidized bed at the bottom of the drying chamber housing 100.
- a particle separator here provided in the form of a main filter (not shown), arranged in the upper part of the drying, covering the cross-section of the dryer housing 100.
- a product outlet 104 is arranged to discharge the dried-hot product from the bottom of the drying chamber housing 100, e.g. a screw conveyor 113 transports the dried-hot product from the outlet of the drying chamber 100 to the inlet of the cooler-dryer 400. This screw conveyor 113 is controlled to semi-continuously or continuously discharge dried-hot material.
- a product cooler-end-dryer arranged downstream of the product outlet 104, is indicated by reference numeral 400, having an inlet 401 connected with a drying chamber 100 and an outlet 402 for cooled-dried product discharge.
- a grid 403 is arranged inside the cooler-end-dryer chamber 400, supplied with medium-temperature air, coming from the CO2 heat pump gas-subcooler 802, to cool and end dry of the final product located inside the cooler- end-dryer chamber.
- a fan 404 is arranged to draw medium-temperature air from the gas-subcooler 802, into grid 403 and through product in the cooler-end-dryer housing 400.
- the fan 404 blows the warmer exiting air through the three-way valve and conduit 406, where the cooler-end-dryer exhaust air is mixed with the ambient air, and then the air flows through the inlet of CO2 heat pump gas-subcooler 802 to be pre-heated to the medium temperature and energy is recovered.
- the product cooler-end-dryer 400 is advantageously kept in motion by an oscillator (not shown).
- the dryer housing 100 further comprises a gas outlet 105 connected with gas conduit 200.
- a box filter 107 (Fig. 1) is arranged in gas conduit 200, to remove and collect very fine particles down to 30 microns or smaller. The filter is described in more details below.
- a condenser 300 is arranged downstream of the box filter 107, to condense vapour and remove liquid in air exhausted from the dryer chamber housing 100. Cooling water, at a temperature at least 5 °C lower than the dew point of the incoming condensing air stream, enters the condenser 300 at cooling water inlet 303, absorbs energy and increases its enthalpy and leaves the condenser 300 at cooling water outlet 304. Condensed liquid is drained at condense outlet 305 and from which the condensate energy can be recovered to preheat the material, screw conveyors or dis integrator.
- a bypass conduit 201 is arranged in the gas conduit 200, connecting the gas inlet 301 and gas outlet 302 of the condenser 300.
- a bypass valve means 202 is arranged in the bypass conduit 201, e.g. a flap or baffle valve, for partial control of flow, humidity and quality.
- the flap valve is opened in cases where the gas flow contains little humidity, as to control humidity and dry air mixture ratio and thus saving energy in the process.
- the present invention operates in wide range of high, medium and low pressures and variable gas- cooler outlet temperatures at the heat pump side and wide range of water removal and capacity at the drying side.
- evaporating temperature ranges from 5 to 10 °C
- gas-cooler outlet temperature between 35 and 50 °C
- evaporating pressure from 40 to 45 bars
- medium pressure between 55 and 58
- bars and high pressure from 90 to 120 bars.
- the pressures are measured and controlled by the electronic expansion valves at state points 2 and 3 for high pressure, states 1 and 10 for low pressure, and states 5, 6 and 11 for medium pressure.
- the low pressure side is selected to attain the required evaporating temperature to satisfactorily condense the vapor and cool drying air to the operating temperature.
- the high pressure side is selected to provide a discharge temperature and gas-cooler outlet temperature sufficient to re-heat both the drying air and the cooler-end- dryer air to the set point temperatures.
- Fig. 2A should be read in conjunction with Fig. 3A which is a pressure versus enthalpy diagram of CO 2.
- the heat pump comprises a closed-loop natural fluid conduit transporting refrigerant at varying pressures and temperatures.
- the heat pump 800 comprises a compressor 801 having an upstream inlet 1 (at state 1 in Fig. 3A) and a downstream compressor outlet 2 with compressed CO2 (at state 2 in Fig. 3A)
- the levels of pressure and enthalpy at the compressor inlet and compressor outlet are indicated by reference numerals 1 and 2 in Fig. 3A, respectively. From the diagram we can see that the pressure has increased from about 45 bars to about 100 bars (example values only).
- the increase in enthalpy from the compressor inlet to the compressor outlet is in the example shown in Fig. 3A about 35 kJ/kg, which is the only workload in the heat pump 800.
- Compressed refrigerant in conduit (state) 2 is then transported to air heater 206 in Fig. 1 (in the heat pump denoted as gas cooler 206) in a dryer circuit and cooled, in this example representing a heat loss from about 500 kJ/kg down to about 345 kJ/kg, representing a heat transfer of about 155 kJ/kg, heat which is transferred to the dryer recycle gas in conduit 207 (Fig. 1), fed to dryer 100.
- the CO2 fluid changes from state 2 to state 3.
- the cooled refrigerant in line 3 (or state 3) is then guided through the recovery gas-subcooler 802 above (in the heat pump denoted as external heat exchanger 802) to liberate additional heat to the drying air in conduit 406 to be supplied to the cooler-end-dryer 400 (Figs. 1 and 2A).
- the heat exchange in external heat exchanger 802 brings the specific enthalpy in the refrigerant further down from about 345 kJ/kg to about 315 kJ/kg, representing an additional extraction of energy in the CO2 heat pump of about 30 kJ/kg refrigerant.
- the loss of enthalpy at this stage in the circuit is illustrated in Fig. 3A from state 3 to state 4 at constant pressure.
- the cooled gas at state 4 is then expanded in an expansion valve 803, e.g. an electronic expansion valve, from a pressure of about 100 bars to about 57 bars, reducing the refrigerant pressure to about 43 bars in state 5.
- an expansion valve 803 e.g. an electronic expansion valve
- prior art heat pumps would proceed with boiling of refrigerant in an evaporator.
- a fan 404 is arranged to draw medium-temperature air from the gas-subcooler 802, into grid 403 and through product in the cooler-end-dryer housing 400. Then, the fan 404 blows the warmer exiting air through the three-way valve and conduit 406, where the cooler-end-dryer exhaust air is mixed with the ambient air, and then the air flows through the inlet of CO2 heat pump gas-subcooler 802 to be pre-heated to the medium temperature and energy is recovered.
- the expanded refrigerant comprising a mixture of gaseous and liquid refrigerant at state 5 is fed to a medium pressure gas-liquid separator 804, from which liquid refrigerant at equilibrium pressure at state 6 is fed to an internal heat exchanger 805, extracting additional heat in the refrigerant from about 315 kJ/kg to about 255 kJ/kg, indicated at state 7, representing an extraction of specific enthalpy of about 60 kJ/kg refrigerant.
- the cooled liquid refrigerant in conduit 7 is throttled and cooled further to state 8 using a medium pressure expansion valve 806.
- the fluid is a mixture of liquid and gas, in this example throttled from about 57 bars to about 45 bars, thus representing a pressure loss of about 12 bars at constant enthalpy.
- the cooled refrigerant mixture at low pressure of 45 bars at state 8 is then supplied to the evaporator 300, which in the dryer circuit operates as a condenser.
- the mixture is boiled reaching state 9.
- the boiling is achieved by taking heat from the externally flowing moist air in associated external process. During this process the moist air is cooled and the vapor is condensed and removed from the drying circuit 305 (Figs. 1 and 2A).
- the heat for boiling the CO2 in the evaporator is recycled in the gas-cooler 206 to reheat the drying air to feed the drying chamber 100 (Fig. 1).
- the specific enthalpy of the refrigerant is increased from about 220 kJ/kg at state 8 to about 435 kJ/kg in conduit or state 9, representing a heat extraction in the heat pump of about 215 kJ/kg.
- the gaseous refrigerant phase in medium pressure separator 804 at equilibrium pressure, indicated at state 11, is fed to a pressure control valve 807 to reduce gas pressure in conduit 12 (at state 12) to the pressure in conduit 10 described immediately above, whereupon the respective refrigerant flows from states 10 and 12, at similar pressure but different temperature, are combined at a junction 810 (Fig. 2A) as a feed at state 1 to compressor 801, thus completing the cycle.
- a second, and preferred embodiment, of the integrated transcritical CO2 heat pump in accordance with the invention is illustrated.
- the fluid After boiling in the evaporator 300, the fluid exits at state 9, which can be a mixture, saturated or slightly superheated vapor.
- state 9 can be a mixture, saturated or slightly superheated vapor.
- the fluid flows into a gas-liquid-oil separator 808, also denoted as second separator 808, which assures that only saturated vapor is supplied to the internal heat exchanger 805 and, consequently, only superheated vapor enters the compressor 801 avoiding its damage by liquid droplets.
- the second separator 808 and its accompanying components replaces junction 810 in the first embodiment.
- the saturated gaseous refrigerant phase at about 57 bars from medium pressure separator 804 at equilibrium pressure at state 11 is fed to a pressure control valve 807 to reduce gas pressure and to become a mixture at state 12.
- the mixture enters the second separator 808, which advantageously allows the return of oil to the compressor.
- the mixture of liquid and oil in conduit 812 enters to the suction line and flows through the internal heat exchanger 805, reaches state 1 and enters the compressor 801.
- the separator 808 supplies cooled saturated gaseous refrigerant in state 10 that undergoes heat exchange against liquid refrigerant in conduit 6, as it flows through the internal heat exchanger 805 described above. Then the refrigerant reaches state 1 as superheated vapor and re-enters the compressor 801 to repeat the cycle. In this process the enthalpy in conduit 10 is increased from about 424 kJ/kg to about 475 kJ/kg at state 1.
- the pressure in the separator 808 is kept to be the same as set point evaporating pressure by the CO2 safety control valve 809 to avoid fluctuating temperatures of the evaporator and the income drying air that is to be cooled and condensed.
- This invention is a green technology using carbon dioxide that is natural fluid with zero ozone depletion and no global warming.
- CO2 is non-toxic, non-corrosive, non-flammable, non-taxable and has no restriction on charge or re-charge.
- CO2 has excellent thermal properties and high volumetric cooling capacity allowing compact components design, such as smaller diameter suction and discharge lines and smaller compressor size.
- CO2 has low critical temperature that allows heat pump operation at transcritical cycle that is desired to attain high gas-cooler pressure and high drying air temperature.
- the use of a closed circuit heat pump excludes the need for substantial infrastructure and cost of water supply.
- the invention operates in closed loop using only CO2, and therefore it avoids both discharge and loss of heated water as in conventional systems.
- the invention also obtains substantial energy savings because there is no need for heating water, only power supply to the compressor. A substantial part of the work input at the compression step is reused in the associated heat consuming in both drying and cooling-end- drying processes. In the exemplified drying process described in the example above, the drying time is reduced, the water removal or drying capacity is increased, and the energy consumption is reduced.
- FIGs. 4-11 are diagrams showing values obtained from simulations at chosen operating conditions:
- Figure 4 shows specific cooling effect versus pressure of a heat pump according to the invention and two prior art heat pumps.
- the invention exhibits a superior cooling effect, which is stable at varying pressure, in the example shown at about 220 kJ/kg, whereas the prior art cooling effects at 90 bars are substantially lower at a high pressure of 120 bars by about 18% and 38%, respectively, of the cooling effect provided by the invention, increasing to about 50% and 80%, respectively, of the cooling effect provided by the invention.
- FIG. 5 is a similar diagram, but where the specific heating effect versus pressure is compared between the invention and the two prior art heat pumps. Also here, the heat pump in accordance with the invention exhibits a substantial improvement compared to prior art.
- the compressor discharge temperature is substantially higher than the prior art. Higher temperature is desired and advantageous for drying at higher water removal rates and capacities.
- Figure 7 demonstrates that the invention exhibits a substantially higher cooling coefficient of performance as a function of pressure compared to the prior art, throughout the whole range of working pressure relevant to processes of this type.
- Figure 8 provides an additional confirmation of the technical effect in that the heating coefficient of performance as a function of pressure is substantially higher than the prior art throughout the whole range of working pressure relevant to processes of this type.
- Figure 9 show the combined coefficient of performance as a function of pressure shown in the Figures 7 and 8 above.
- the combined coefficient of performance represents two unique characteristics of the CO2 heat pump dryer in this invention. Firstly, it uses condensing energy for air heating the drying air and the cooling-end-drying air. Secondly, it uses the evaporating energy to cool the dry-air, to condense the vapor fraction and remove the liquid water from the drying loop. This indicates a unique aspect of the invention in which the CO2 heat pump dryer is capable to simultaneously use and recycle energy from both the refrigeration and heat pump cycles.
- Figure 10 demonstrates a lower actual work input for the invention than the prior art heat pumps.
- the low actual work is accompanied by a significant increased cooling capacity due to the separator 804, which operates between the CO2 critical and evaporating pressures and feeds only liquid phase that is subcooled before throttling to evaporating pressure.
- the separator 804 operates between the CO2 critical and evaporating pressures and feeds only liquid phase that is subcooled before throttling to evaporating pressure.
- the mixture released by the expansion valve approaches the saturation liquid line (see diagrams), and the cooling effect is maximized.
- the prior art heat pumps may allow liquid droplets to enter and damage the compressor, whereas the invention includes superheat by using the internal heat exchange and separator, both assuring that only superheated vapor flows through the compressor protecting it.
- both devices provide a higher discharge temperature desired for heating the drying air.
- the heat pump can operate at a substantially higher efficiency and with a smaller compressor than the prior art.
- the volumetric flow rate at 90 bars is about 4.3 and 2.7 times larger for the prior art heat pumps, and at 120 bars the rates are about 1.4 and 1.2 times larger for the prior art systems.
Abstract
Description
Claims
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
NO20191289A NO345812B1 (en) | 2019-10-28 | 2019-10-28 | Improved heat pump |
PCT/NO2020/050259 WO2021086196A1 (en) | 2019-10-28 | 2020-10-22 | Improved heat pump |
Publications (2)
Publication Number | Publication Date |
---|---|
EP4051971A1 true EP4051971A1 (en) | 2022-09-07 |
EP4051971A4 EP4051971A4 (en) | 2023-11-15 |
Family
ID=75714544
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP20882090.2A Pending EP4051971A4 (en) | 2019-10-28 | 2020-10-22 | Improved heat pump |
Country Status (3)
Country | Link |
---|---|
EP (1) | EP4051971A4 (en) |
NO (1) | NO345812B1 (en) |
WO (1) | WO2021086196A1 (en) |
Family Cites Families (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH11142007A (en) * | 1997-11-06 | 1999-05-28 | Nippon Soken Inc | Refrigerating cycle |
JP3614330B2 (en) * | 1999-10-20 | 2005-01-26 | シャープ株式会社 | Supercritical vapor compression refrigeration cycle |
US6457325B1 (en) * | 2000-10-31 | 2002-10-01 | Modine Manufacturing Company | Refrigeration system with phase separation |
RU2472078C2 (en) * | 2007-11-13 | 2013-01-10 | Керриер Корпорейшн | Refrigeration systems and method of cold generation |
WO2010117973A2 (en) * | 2009-04-09 | 2010-10-14 | Carrier Corporation | Refrigerant vapor compression system with hot gas bypass |
JP5240332B2 (en) * | 2011-09-01 | 2013-07-17 | ダイキン工業株式会社 | Refrigeration equipment |
EP3023712A1 (en) * | 2014-11-19 | 2016-05-25 | Danfoss A/S | A method for controlling a vapour compression system with a receiver |
EP3303944A1 (en) * | 2015-06-08 | 2018-04-11 | Danfoss A/S | A method for operating a vapour compression system with heat recovery |
JP6589537B2 (en) * | 2015-10-06 | 2019-10-16 | 株式会社デンソー | Refrigeration cycle equipment |
JP6749392B2 (en) * | 2015-10-20 | 2020-09-02 | ダンフォス アクチ−セルスカブ | Method of controlling vapor compression system in flooded condition |
ITUA20163465A1 (en) * | 2016-05-16 | 2017-11-16 | Epta Spa | REFRIGERATOR SYSTEM WITH MORE LEVELS OF EVAPORATION AND METHOD OF MANAGEMENT OF SUCH A SYSTEM |
US10830499B2 (en) * | 2017-03-21 | 2020-11-10 | Heatcraft Refrigeration Products Llc | Transcritical system with enhanced subcooling for high ambient temperature |
EP3619481A4 (en) * | 2017-05-02 | 2021-01-27 | Rolls-Royce North American Technologies, Inc. | Method and apparatus for isothermal cooling |
NO20180066A1 (en) * | 2018-01-16 | 2019-07-08 | Waister As | System and method of drying solid materials and liquid-solid mixtures |
-
2019
- 2019-10-28 NO NO20191289A patent/NO345812B1/en unknown
-
2020
- 2020-10-22 WO PCT/NO2020/050259 patent/WO2021086196A1/en unknown
- 2020-10-22 EP EP20882090.2A patent/EP4051971A4/en active Pending
Also Published As
Publication number | Publication date |
---|---|
NO20191289A1 (en) | 2021-04-29 |
WO2021086196A1 (en) | 2021-05-06 |
NO345812B1 (en) | 2021-08-16 |
EP4051971A4 (en) | 2023-11-15 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP2468946B1 (en) | A heat pump system for a laundry dryer and a method for operating a heat pump laundry dryer | |
Schmidt et al. | Applying the transcritical CO2 process to a drying heat pump | |
CA2655281C (en) | Process and plant for treatment of wet material | |
US8006503B2 (en) | Energy recovery system and method for a refrigerated dehumidification process | |
CN110127984A (en) | A kind of sludge at low temperature heat pump drying equipment | |
JP2005279257A (en) | Dryer and operation method thereof | |
CN211601490U (en) | Heat pump type low-temperature coal slime drying system based on low-temperature heat pipe | |
EP2551401A1 (en) | A heat pump system for a laundry dryer | |
CN107270696A (en) | One kind is based on CO2The drying system of Trans-critical cycle heat pump cycle | |
CN208454788U (en) | A kind of low temperature drying equipment handling sludge | |
CA3087364A1 (en) | Modular system and process of drying solids and liquid-solid mixtures | |
CN108870878A (en) | Direct heat pump integrates transformation drying system and method | |
JP4931791B2 (en) | Refrigeration air conditioner | |
KR20150117529A (en) | Heat pump type drying apparatus | |
EP4051971A1 (en) | Improved heat pump | |
JP5568838B2 (en) | Industrial drying system | |
Sarkar | Performance characteristics of multi-evaporator transcritical CO2 refrigeration cycles with hybrid compression/ejection | |
EP2551402A1 (en) | A heat pump system for a laundry dryer | |
CN106196894A (en) | Utilize the brown coal drying of heat recovery circuit | |
Alves-Filho | Energy effective and green drying technologies with industrial applications | |
CN207081023U (en) | A kind of smoke processing system for power plant desulfurization dehydration drop mist | |
CA2346138A1 (en) | Method and installation for drying a textile mass | |
CN107166418A (en) | A kind of smoke processing system that drop mist is dehydrated for power plant desulfurization | |
CN206831868U (en) | A kind of multifunctional cold and hot water air-conditioner set | |
JP5318153B2 (en) | Refrigeration air conditioner |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE |
|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE |
|
17P | Request for examination filed |
Effective date: 20220525 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
DAV | Request for validation of the european patent (deleted) | ||
DAX | Request for extension of the european patent (deleted) | ||
P01 | Opt-out of the competence of the unified patent court (upc) registered |
Effective date: 20230526 |
|
A4 | Supplementary search report drawn up and despatched |
Effective date: 20231016 |
|
RIC1 | Information provided on ipc code assigned before grant |
Ipc: F25B 40/00 20060101ALI20231010BHEP Ipc: F25B 30/06 20060101ALI20231010BHEP Ipc: F25B 25/00 20060101ALI20231010BHEP Ipc: F26B 23/00 20060101ALI20231010BHEP Ipc: C02F 11/13 20190101ALI20231010BHEP Ipc: F25B 40/06 20060101ALI20231010BHEP Ipc: F25B 9/00 20060101ALI20231010BHEP Ipc: F25B 1/00 20060101ALI20231010BHEP Ipc: F25B 30/02 20060101AFI20231010BHEP |