CN106568253B

CN106568253B - Efficient ice making device and method

Info

Publication number: CN106568253B
Application number: CN201610953622.5A
Authority: CN
Inventors: 胡涛; 张冀; 苏华山; 唐海波
Original assignee: China Three Gorges University CTGU
Current assignee: China Three Gorges University CTGU
Priority date: 2016-11-03
Filing date: 2016-11-03
Publication date: 2022-05-20
Anticipated expiration: 2036-11-03
Also published as: CN106568253A

Abstract

The invention discloses a high-efficiency ice making device and a method, which comprises a water chilling unit, wherein the water chilling unit is connected with a heat exchanger in series, an air pump and a second regulating valve are connected in series on a branch at the other side of the heat exchanger, a fluid ice storage tank is connected behind the second regulating valve, a nozzle is arranged at the top end inside the fluid ice storage tank, a pipeline where the nozzle is located is connected with a first regulating valve, a circulating water pump and a switch valve are arranged at the bottom of the fluid ice storage tank through a pipeline, the first regulating valve and the switch valve are simultaneously connected with a throttle valve, and the other end of the throttle valve is connected with the heat exchanger. The problems of overlarge corrosivity and refrigerant consumption of a direct contact method, low heat exchange efficiency, high energy consumption and the like of other ice slurry preparation methods are solved.

Description

Efficient ice making device and method

Technical Field

The invention relates to a device for preparing flow state ice slurry by directly contacting and carrying out phase change by using a specific thermophysical working medium with two properties (the evaporation temperature is slightly lower than 0 ℃ under normal pressure and is insoluble in water), such as n-butane (the evaporation temperature is 1atm and is-0.5 ℃), tetrafluoro-monochloroethane R124 (the evaporation temperature is 1atm and is-10.9 ℃), and the like. Because the supercooling degree is extremely low, when the evaporation temperature of the working medium is-0.5 ℃, the ice making efficiency of the system can reach about 160 percent of the performance coefficient of the traditional wall surface scraping type ice slurry making system.

Background

The ice slurry is a mixture of fine ice crystal particles and water solution, and has good fluidity, heat transfer property and energy storage property, so that the ice slurry becomes an ideal cold storage and cold transmission medium. Currently, ice slurry technology exhibits its specific advantages in many areas, such as: an ice cold storage air conditioning system, and the fields of food preparation and processing industry, fishery, medical treatment, refrigeration, industrial process cooling and the like. The preparation method of the fluid ice slurry mainly comprises the following steps: a scraping method, a supercooled water method, a vacuum method, a fluidized bed method, a direct contact method, and the like. In the several methods for preparing the flow state ice slurry, the direct contact method has the advantages of highest heat exchange efficiency, relatively low energy consumption, simple structure and high safety, ice blockage is not easy to form, and the method is an ideal ice slurry preparation technology. Meanwhile, the scraping method is actually mature and widely used in engineering, but the scraping method is a wall surface heat transfer mode, the thermal resistance is large, the corresponding supercooling degree is large (generally ranging from minus 19 ℃ to minus 10 ℃), and the heat exchange efficiency is low; and the existence of the wiper moving part complicates the system manufacturing and requires excessive power consumption of the moving part, resulting in low overall ice making efficiency.

Disclosure of Invention

The invention aims to solve the problems of overlarge corrosivity and refrigerant consumption of a direct contact method, low heat exchange efficiency, high energy consumption and the like of other ice slurry preparation methods.

In order to solve the technical problems, the invention provides the following technical scheme: the utility model provides a high-efficient system ice device, it includes the cooling water set, the cooling water set establishes ties with the heat exchanger, it has air pump and second governing valve to establish ties on the heat exchanger opposite side branch road, be connected with the flow state ice holding tank behind the second governing valve, the nozzle is installed on the inside top of flow state ice holding tank, be connected with first governing valve on the nozzle place pipeline, circulating water pump and ooff valve are installed through the pipeline in the bottom of flow state ice holding tank, first governing valve and ooff valve link to each other with the choke valve simultaneously, the other end and the heat exchanger of choke valve link to each other.

The ice making device adopts liquid n-butane or tetrafluoro-monochloroethane as a water-insoluble working medium to directly contact with water, and after mixing, the mixture is sprayed, depressurized and evaporated to continuously prepare fine flow state ice slurry.

The highest pressure in the ice making device is controlled within 2.5atm, and the highest pressure value is less than 1.6atm when n-butane is used as a working medium.

An ice making method using an efficient ice making apparatus, comprising the steps of:

1) the method comprises the following steps of preparing 4 ℃ cold water by using an air source through a small water chilling unit 1, conveying the cold water to a spiral sleeve type heat exchanger 2, exchanging heat with superheated R124 steam compressed and conveyed by an air pump 3, condensing the R124 into a supercooled liquid, meanwhile, returning the 4 ℃ cold water to the water chilling unit 1 after exchanging heat and heating in the spiral sleeve type heat exchanger 2, cooling to 4 ℃ again, and circulating;

2) the ice making circulation is carried out, the upper space in the fluid ice storage tank is superheated steam tetrafluoro-monochloroethane R124 at about 0 ℃, the pressure of the superheated steam tetrafluoro-monochloroethane R124 is about 1.64atm, the superheated steam tetrafluoro-monochloroethane R124 is compressed and further superheated to 10 ℃ under the action of the air pump 3 through the second regulating valve 9, the superheated steam tetrafluoro-monochloroethane R enters the spiral heat exchanger 2 and is condensed to be liquid R124 at about 4 ℃, the liquid R124 is throttled and decompressed to about 1.95atm through the throttle valve 6 and is mixed with chilled water sent by the circulating water pump 4at about 0 ℃ and 11, the temperature of the two mixed liquids is between 0 and 4 ℃, and the mixing temperature can be close to 0 ℃ as far as possible by controlling the opening degree of the throttle valve;

3) the mixed liquid close to 0 ℃ passes through the first regulating valve 7 along the pipeline under the action of the circulating water pump 4, finally enters the nozzle 8, is sprayed into the fluid ice storage tank 10, the second regulating valve 9 is controlled to keep the pressure of the upper space of the fluid ice storage tank 10 at about 1.6atm, the mixed liquid of the water and the liquid R124 is suddenly reduced to 1.6atm because the saturated evaporation pressure of the liquid R124 at 4 ℃ is 1.9atm, the liquid R124 in the mixed liquid is evaporated and phase-changed in the upper space of the fluid ice storage tank 10, a large amount of heat required by evaporation comes from the frozen water drops sprayed together, the frozen water drops release heat and supercool in a large amount in a short time to freeze into fine ice crystals, and finally fall into the frozen water stored in the fluid ice storage tank 10 to become fluid ice;

4) the stored fluid ice in the fluid ice storage tank 10 is basically concentrated on the upper part of the liquid, the lower part of the liquid ice is still frozen water with the temperature of 0 ℃, the frozen water is continuously sent to the position 11 to be mixed with the liquid R124 under the action of the circulating water pump 4, and the reciprocating circulation is carried out to prepare fluid ice slurry.

The invention has the following beneficial effects:

1. the fluid ice slurry is prepared by adopting a specific thermophysical working medium containing two properties (the evaporation temperature under normal pressure is slightly lower than 0 ℃ and the working medium is insoluble in water), such as n-butane (the evaporation temperature of 1atm is minus 0.5 ℃), tetrafluoro-monochloroethane R124 (the evaporation temperature of 1atm is minus 10.9 ℃) and the like, to directly contact and generate phase change.

2. The supercooling degree of the ice slurry preparation device is extremely low during operation, and when the evaporation temperature of the working medium is-0.5 ℃, the ice preparation efficiency of the ice slurry preparation device can reach about 160% of the performance coefficient of a traditional wall scraping type ice slurry preparation system theoretically to the maximum.

3. Because the adopted working medium is n-butane and tetrafluoro-monochloroethane R124 which are insoluble in water and do not react with water to form corrosive substances, the problem of corrosivity of a direct contact method is well solved.

4. The heat exchange efficiency is greatly improved because the n-butane and the tetrafluoro-monochloroethane R124 are directly contacted with the ice making solution without wall thermal resistance.

5. Since the highest pressure inside the whole system operation is lower than 2.5atm, the safety and reliability are high, and the manufacturing cost of the device is low.

Drawings

The invention is further illustrated by the following figures and examples.

FIG. 1 is a schematic view of an efficient ice making apparatus.

Fig. 2 is an explanatory schematic view of an indication of a fluidized ice making cycle.

In the figure: the system comprises a water chilling unit 1, a heat exchanger 2, an air pump 3, a circulating water pump 4, a switch valve 5, a throttle valve 6, a first regulating valve 7, a nozzle 8, a second regulating valve 9 and a fluid ice storage tank 10.

Detailed Description

Embodiments of the present invention will be further described with reference to the accompanying drawings.

Example 1:

as shown in fig. 1-2, a high-efficient ice making device, it includes cooling water set 1, cooling water set 1 establishes ties with

heat exchanger

2, 2 opposite side branches of heat exchanger establish ties on have air pump 3 and second governing valve 9, be connected with flow state ice holding tank 10 behind the second governing valve 9, nozzle 8 is installed on the inside top of flow state ice holding tank 10, be connected with first governing valve 7 on the pipeline of nozzle 8 place, there are circulating water pump 4 and ooff valve 5 bottom of flow state ice holding tank 10 through the pipe-line mounting, first governing valve 7 and ooff valve 5 link to each other with choke valve 6 simultaneously, the other end of choke valve 6 links to each other with heat exchanger 2.

Further, the ice making device adopts liquid n-butane or tetrafluoro-monochloroethane as a water-insoluble working medium to directly contact with water, and after mixing, the mixture is sprayed, depressurized and evaporated to continuously prepare fine flow state ice slurry.

Further, the highest pressure inside the ice making device is controlled within 2.5 atm.

Example 2:

in this embodiment, tetrafluoromonochloroethane R124 is selected as the ice making working medium, the external cold source adopts a small chiller 1, and the external cold source circulates (see a-a loop in fig. 2): a small-sized water chilling unit 1 is adopted, cold water with the temperature of 4 ℃ is prepared by an air source and then is conveyed to a spiral sleeve type heat exchanger 2, the cold water exchanges heat with overheated R124 steam which is compressed and conveyed by an air pump 3, R124 is condensed into supercooled liquid, meanwhile, the cold water with the temperature of 4 ℃ exchanges heat in the spiral sleeve type heat exchanger 2, the cold water returns to the water chilling unit 1 after being heated, and the temperature of the cold water is lowered to 4 ℃ again, and the circulation is carried out.

Ice making cycle (see circuit B-B, C-C, D in FIG. 2): the superheated steam tetrafluoro-monochloroethane R124 with the temperature of about 0 ℃ in the upper space of the fluid ice storage tank has the pressure of about 1.64atm, is compressed and further superheated to 10 ℃ under the action of the air pump 3 through the second regulating valve 9, has the pressure of about 2.3atm, enters the spiral double-pipe heat exchanger 2 to be condensed into liquid R124 with the temperature of about 4 ℃, is throttled and depressurized to about 1.95atm through the throttle valve 6, is mixed with the chilled water sent by the circulating water pump 4at about 0 ℃ at 11 shown in figure 2, and the two mixed liquids (the temperature is between 0 and 4 ℃ and can be controlled to be as close to 0 ℃ as possible) pass through the first regulating valve 7 along the pipeline under the action of the circulating water pump 4 and finally enter the nozzle 8 to be sprayed into the fluid ice storage tank 10, the second regulating valve 9 is controlled to keep the pressure of the upper space of the fluid ice storage tank 10 at about 1.6atm, since the saturated evaporation pressure of the liquid R124 at 4 ℃ is 1.9atm, the liquid R124 is sprayed from the nozzle 8, the pressure of the mixed liquid of the water and the liquid R124 is suddenly reduced to 1.6atm, the liquid R124 in the mixed liquid is subjected to evaporation phase change (the evaporation temperature is about-0.5 ℃, namely the supercooling degree of the frozen water at 0 ℃ after balance is about 0.5 ℃), a large amount of heat required for evaporation comes from the frozen water drops sprayed together, the frozen water drops largely release heat and are supercooled in a very short time to be frozen into fine ice crystals, and finally the frozen water drops fall into the frozen water stored in the fluid ice storage tank 10 to become fluid ice. The stored fluid ice in the fluid ice storage tank 10 is basically concentrated on the upper part of the liquid, the lower part of the liquid ice is still frozen water with the temperature of 0 ℃, the frozen water is continuously sent to the position 11 to be mixed with the liquid R124 under the action of the circulating water pump 4, and the reciprocating circulation is carried out to prepare fluid ice slurry.

Therefore, the preparation of the flow state ice slurry under a lower supercooling degree (0.5 ℃) can be realized, and the ice making circulation efficiency of the system is greatly improved.

From the above description, those skilled in the art can make various changes and modifications without departing from the technical spirit of the present invention, and all such changes and modifications are within the scope of the present invention. The present invention is not limited to the details given herein, but is within the ordinary knowledge of those skilled in the art.

Claims

1. The ice making method of the efficient ice making device comprises a water chilling unit (1), wherein the water chilling unit (1) is connected with a heat exchanger (2) in series, an air pump (3) and a second regulating valve (9) are connected on a branch at the other side of the heat exchanger (2) in series, a fluid ice storage tank (10) is connected behind the second regulating valve (9), a nozzle (8) is installed at the top end inside the fluid ice storage tank (10), a first regulating valve (7) is connected on a pipeline where the nozzle (8) is located, a circulating water pump (4) and a switch valve (5) are installed at the bottom of the fluid ice storage tank (10) through pipelines, the first regulating valve (7) and the switch valve (5) are simultaneously connected with a throttling valve (6), and the other end of the throttling valve (6) is connected with the heat exchanger (2);

characterized in that the ice making method comprises the following steps:

1) the method comprises the following steps of preparing 4 ℃ cold water by using an air source through a small water chilling unit (1), conveying the cold water to a spiral sleeve type heat exchanger (2), exchanging heat with superheated R124 steam compressed and conveyed by an air pump (3), condensing the R124 into a supercooled liquid, meanwhile, returning the 4 ℃ cold water to the water chilling unit (1) after exchanging heat and heating in the spiral sleeve type heat exchanger (2), cooling to 4 ℃ again, and circulating;

2) the ice making circulation is carried out, superheated steam tetrafluoro-monochloroethane R124 with the temperature of about 0 ℃ is arranged in the upper space of the fluid ice storage tank, the pressure of the superheated steam tetrafluoro-monochloroethane R124 is about 1.64atm, the superheated steam tetrafluoro-monochloroethane R124 is compressed and further superheated to 10 ℃ under the action of an air pump (3) through a second regulating valve (9), the superheated steam tetrafluoro-monochloroethane R enters a spiral sleeve type heat exchanger (2) to be condensed into liquid R124 with the temperature of about 4 ℃, the liquid R124 is throttled and reduced to about 1.95atm through a throttle valve (6) and then is mixed with chilled water sent by a circulating water pump (4) at a temperature of about 0 ℃ and (11), the temperature of the two mixed liquids is between 0 and 4 ℃, and the mixing temperature of the two liquids can be close to 0 ℃ as far as possible by controlling the opening degree of the throttle valve;

3) the mixed liquid with the temperature close to 0 ℃ passes through a first regulating valve (7) along a pipeline under the action of a circulating water pump (4) and finally enters a nozzle (8) to be sprayed into a fluid ice storage tank (10), the pressure of the upper space of the fluid ice storage tank (10) is kept at about 1.6atm by controlling a second regulating valve (9), the saturated evaporation pressure of the liquid R124 at the temperature of 4 ℃ is 1.9atm, the mixed liquid of the water and the liquid R124 is suddenly reduced to 1.6atm, the liquid R124 in the mixed liquid is subjected to evaporation phase change in the upper space of the fluid ice storage tank (10), a large amount of heat required by evaporation comes from the frozen water drops sprayed together, the frozen water drops are subjected to large-amount heat release and supercooling in a short time to be frozen into fine ice crystals, and finally fall into the frozen water stored in the fluid ice storage tank (10) to become fluid ice;

4) the stored fluid ice in the fluid ice storage tank (10) is basically concentrated at the upper part of the liquid, the lower part of the liquid ice is still frozen water with the temperature of 0 ℃, the frozen water is continuously sent to the position (11) to be mixed with the liquid R124 under the action of the circulating water pump (4), and the reciprocating circulation is carried out to prepare fluid ice slurry.

2. An ice making method of an efficient ice making apparatus as claimed in claim 1, wherein: the ice making device adopts liquid n-butane or tetrafluoro-monochloroethane R124 as a water-insoluble working medium to directly contact with water, and after mixing, the mixture is sprayed, depressurized and evaporated to continuously prepare fine flow state ice slurry.

3. An ice making method of an efficient ice making apparatus as claimed in claim 1, wherein: the highest pressure in the ice making device is controlled within 2.5atm, and the highest pressure value is less than 1.6atm when n-butane is used as a working medium.