CN102062507B - Flow ice making method and device based on lithium bromide absorption type refrigeration cycle - Google Patents

Abstract

The invention utilizes concentrated lithium bromide solution to continuously absorb water vapor in the absorber to form a low-pressure environment in the evaporative freezing chamber, so that the water continuously evaporates and absorbs its own heat in the low-pressure environment of the evaporative freezing chamber, and partially freezes to form liquid ice. After the lithium bromide solution absorbs the water vapor from the evaporative freezer in the absorber and is diluted, it is pumped to the generator to be heated and regenerated. The concentration of the solution is increased, and it has moisture absorption capacity again, and then it is cooled and sent to the absorber. It constitutes a solution absorption-regeneration reciprocating cycle. The water vapor from the generator is condensed into supercooled water in the condenser, and then sent to the evaporative freezer to make ice after throttling. The ice making system is automatically replenished by the water tank according to the water level of the evaporative freezer.

Description

Method and device for producing liquid ice based on lithium bromide absorption refrigeration cycle

technical field

The present invention relates to a new method of producing liquid ice by evaporative freezing, which is a method and device for producing liquid ice by evaporative freezing based on lithium bromide solution absorption refrigeration cycle, and belongs to heat-driven refrigeration and liquid ice production. technology field.

Background technique

With the emergence of energy shortages, the energy consumption of air-conditioning systems caused by the wide application of refrigeration and air-conditioning equipment has aroused widespread concern in the current society. Energy conservation has become an urgent requirement in the refrigeration field under the new situation. my country has also proposed the sustainable development of the country. strategy. As an important means of saving energy and shifting peaks and valleys, cold storage has important practical significance and application value. Among them, ice storage has the advantages of large latent heat of phase change and low cost. Traditional ice energy storage has disadvantages such as low evaporation temperature, large heat transfer temperature difference in the production process, and low refrigeration performance coefficient. Fluid ice has become a promising application form of ice storage due to its good thermophysical properties and flow characteristics. Therefore, it is of great significance to research and develop new and efficient methods for producing liquid ice.

Contents of the invention

Technical problem: The present invention provides a lithium bromide-based absorption refrigeration cycle with energy saving, simple structure and easy operation.

Ring liquid ice preparation method and device.

Technical solution: In order to solve the above technical problems, the technical solution provided by the invention is:

The technical solution of the invention is to change and transform the evaporator in the traditional lithium bromide absorption refrigeration cycle into a flow ice production module, and realize it with auxiliary functional components.

The liquid ice preparation device based on the lithium bromide absorption refrigeration cycle of the present invention is composed of a solution circulation loop and an evaporative freezing ice-making module; the solution circulation loop includes a generator, an absorber, a solution heat exchanger, a cooler, and a first solution pump , the second solution pump, and the refrigerant water pump; wherein, the concentrated solution area in the lower part of the absorber is connected to the lower part of the generator through the first solution pump, the second solution pump and the solution heat exchanger respectively, and the input end of the cooler passes through the solution heat The exchanger is connected to the lower part of the generator, and the output end of the cooler is connected to the sprinkler on the upper part of the absorber;

The evaporative freezing ice-making module consists of a condenser, a water supply device, a throttle valve, an evaporative freezing chamber, an ice forming device, an ice-water separation device, a one-way valve, an intermediate ice storage device, a one-way valve, and an ice storage tank; the lower part of the condenser The concentrated solution area of the cooling tower is connected to the evaporative freezing chamber through a throttle valve, and the output end of the evaporative freezing chamber is connected to the ice storage tank through a one-way valve, an intermediate ice storage device, and a one-way valve in sequence; the output end at the bottom of the cooling tower is sequentially passed through a water pump and an absorber , The condenser returns to the input end of the upper part of the cooling tower.

In the evaporative freezing chamber, the concentrated solution area in the lower part of the evaporative freezing chamber is connected to the sprinkler located in the upper part of the evaporative freezing chamber through a refrigerant water pump, and an ice-forming device is installed in the lower part of the sprayer, and ice water is installed in the lower part of the ice-forming device. separation device.

The method for producing fluid ice based on the fluid ice producing device of the lithium bromide absorption refrigeration cycle of the present invention is that the concentrated solution of the absorber is sent to the generator through the solution heat exchanger through the solution pump, and the The final dilute solution enters the absorber through the solution heat exchanger and cooler under the action of the differential pressure between the generator and the absorber to form a solution circulation loop; in the process of evaporative ice making, the water supply device supplies water to the condenser, and the water in the condenser It enters the evaporative freezing chamber through the throttle valve, and the ice-water mixture formed on the ice-forming device in the evaporative freezing chamber passes through the ice-water separation device, one-way valve, intermediate ice storage room, and one-way valve into the ice storage tank to complete the ice-making process .

This method uses the concentrated solution in the absorber to absorb the steam in the evaporative freezing chamber to create a low-pressure environment for the evaporative freezing chamber, in which water evaporates and absorbs its own heat, and grows into liquid ice on the ice-forming device.

The ice-water separation process of this method is that the ice crystals formed on the ice-forming device are separated by the ice-water separation device, the intermediate ice storage is kept at the same pressure as that in the evaporative freezing chamber, and the one-way valve is opened to enter the intermediate ice storage chamber, and then Close the one-way valve, open the one-way valve and the ice crystals enter the ice storage tank to complete the ice-water separation process; after the ice-water separation is completed, the intermediate ice storage chamber is evacuated by a vacuum pump.

Beneficial effect:

1. This method can use industrial waste heat, solar energy and other heat sources with a temperature of about 100 ℃ as the driving energy of the generator, which saves a lot of electric energy and realizes the sustainable development of energy utilization.

2. This device can be directly transformed from a lithium bromide absorption refrigeration device. It has a simple structure and stable operation, and can overcome the shortcomings of mechanical exhaust manufacturing vacuum wear, high noise, and difficulty in continuous operation.

3. The method and device provide a feasible method and solution for producing liquid ice, which can be realized only by modifying and upgrading the absorption refrigeration device with mature technology.

Description of drawings

Fig. 1 is a structural representation of the present invention;

Among them: generator 1, condenser 2, water tank 3, throttle valve 4, evaporative freezing chamber 5, ice forming device 6, ice-water separator 7, intermediate ice storage device 8, ice storage tank 9, absorber 10, Solution heat exchanger 11, first one-way valve 12, second one-way valve 13, cooling tower 14, cooler 15, first solution pump 16, second solution pump 17, refrigerant water pump 18, water pump 19, vacuum pump 20 , the heat source heats the fluid 21, and the water replenishment throttle valve 22.

Detailed ways

The device consists of a solution circulation loop and an evaporative freezing ice-making module; the solution circulation loop includes a generator 1, an absorber 10, a solution heat exchanger 11, a cooler 15, a first solution pump 16, a second solution pump 17, a refrigerant Water pump 18; evaporative freezing ice-making module consists of condenser 2, water supply device 3, throttle valve 4, evaporative freezing chamber 5, water supply throttle valve 22 connecting water replenishing device 3 and evaporative freezing chamber 5, ice forming device 6, ice water Separation device 7, one-way valve 12, intermediate ice storage 8, one-way valve 13, and ice storage tank 9; the condensed water in condenser 2 is connected to evaporative freezing chamber 5 through throttle valve 4, and the output of evaporative freezing chamber 5 The end sequence is connected to the ice storage tank 9 through the one-way valve 12, the intermediate ice storage container 8, and the one-way valve 13.

In the evaporative freezing chamber 5, the refrigerant water zone at the lower part of the evaporative freezing chamber 5 is connected to the shower located at the upper part of the evaporative freezing chamber 5 through a refrigerant water pump 18, and an ice forming device 6 is arranged at the lower part of the shower, and the ice forming device The bottom of 6 is provided with ice-water separator 7.

The method for producing fluid ice by evaporative freezing based on lithium bromide solution absorption refrigeration cycle comprises two processes of solution circulation and evaporative freezing to obtain fluid ice. The specific plan is as follows:

The lithium bromide solution circulation process is similar to the solution circulation in the traditional lithium bromide absorption refrigeration cycle. The solution is used in the absorber to absorb the water vapor in the evaporative freezer to maintain a low water vapor pressure in the evaporative freezer, which is lower than 622.8 Pa (the saturated phase transition pressure corresponding to water at 0°C), the solution is diluted after absorbing water and the concentration is reduced. The dilute lithium bromide solution passes through the solution pump and is heated and regenerated in the generator. The concentration is increased and the ability to absorb water vapor is restored. The process of producing liquid ice by evaporative freezing is that the concentrated solution in the absorber continuously absorbs the water vapor from the evaporator to create a low-pressure environment (less than 622.8Pa) in the evaporative freezing chamber, and the supercooled water in the condenser enters the evaporative freezing chamber after throttling , because the pressure in the evaporative freezing chamber is lower than the phase transition pressure 622.8Pa corresponding to 0°C water, the water in the evaporative freezing chamber will continue to evaporate and absorb its own heat, and the temperature will gradually drop to 0°C, or even lower than 0°C. The liquid ice is generated on the device through decooling, and the liquid ice is separated by an ice-water separation device with a certain structure. The frozen water at the bottom of the evaporation freezer is continuously sprayed on the ice forming device, and ice crystals or ice particles are gradually formed. With the continuous reduction of moisture in the ice-making cycle, a water replenishment device is added on the side of the evaporative freezer.

During the evaporative ice-making process, the water replenishment device 3 automatically replenishes water in the evaporative freezer 5 according to the minimum water level requirement in the evaporative freezer 5. In the evaporative freezing chamber 5, the water of the condenser enters the evaporative evaporative freezing chamber 5 through the throttle valve 4, and the ice-water mixture formed on the ice-forming device 6 in the evaporative evaporative freezing chamber 5 passes through the ice-water separation device 7, the one-way valve 12, The middle ice storage chamber 8 and the one-way valve 13 enter the ice storage tank 9 to complete the ice making process.

In the present invention, the water vapor generated by the generator driven by a heat source above 100°C enters the condenser, and the concentration of the lithium bromide solution after generation is increased, and after being cooled by the heat exchanger and cooling water, it is sprayed into the absorber and absorbed from the evaporation and freezing chamber. The water vapor in the absorption process, the heat released by the water vapor into the liquid is taken away by the cooling water from the cooling tower, and the concentration of the lithium bromide solution after the absorption is reduced, and then sent to the generator through the heat exchanger through the solution pump to complete the solution generation. process. The water vapor from the generator is cooled by the cooling water from the cooling tower in the condenser, condensed into supercooled water, and then sprayed to the evaporative freezing chamber after being throttled by the throttling device, and evaporated on the ice forming device in the evaporative freezing chamber And freeze into ice crystals, the evaporated water vapor is absorbed by the concentrated solution in the absorber, maintaining the low pressure environment in the evaporation and freezing chamber. In order to prevent the water in the system from continuously turning into ice particles, the water in the circulation is reduced, and the water replenishment device is used to replenish water in the condenser at an appropriate time to maintain the amount of water in the system circulation. When the ice crystals in the ice-water separator in the evaporative freezing chamber accumulate to a certain amount, open the one-way valve between the evaporative freezing chamber and the intermediate ice storage, and the ice crystals enter the intermediate ice storage under the action of gravity, and then close the one-way valve . When the ice crystals in the intermediate ice storage reach a certain amount, open the one-way valve between the intermediate ice storage and the ice storage tank, remove the generated ice crystals or ice particles, then close the one-way valve, and turn on the vacuum pump to ensure the intermediate ice storage A certain degree of vacuum.

Claims (5)

1. A liquid ice production device based on a lithium bromide absorption refrigeration cycle, characterized in that the device is composed of a solution circulation loop and an evaporative freezing ice-making module; the solution circulation loop includes a generator (1), an absorber (10) , solution heat exchanger (11), cooler (15), first solution pump (16), second solution pump (17); wherein, the concentrated solution area in the lower part of the absorber passes through the first solution pump and the second solution pump respectively. The solution pump and the solution heat exchanger are connected to the lower part of the generator, the input end of the cooler is connected to the lower part of the generator through the solution heat exchanger, and the output end of the cooler is connected to the sprinkler on the upper part of the absorber; the evaporative freezing ice-making module is composed of Condenser (2), replenishing water device (3), throttle valve (4), evaporative freezing chamber (5), water replenishing throttle valve (22) connecting water replenishing device (3) and evaporative freezing chamber (5), ice forming Device (6), ice-water separation device (7), first one-way valve (12), intermediate ice storage (8), second one-way valve (13), ice storage tank (9), refrigerant water pump ( 18) composition; the condensed water in the condenser (2) is connected to the evaporative freezer (5) through the throttle valve (4), and the output end of the evaporative freezer (5) passes through the first one-way valve (12), intermediate storage The ice container (8) and the second one-way valve (13) are connected to the ice storage tank (9). the 2. The liquid ice production device based on lithium bromide absorption refrigeration cycle according to claim 1, characterized in that, in the evaporative freezing chamber (5), the refrigerant water zone at the lower part of the evaporative freezing chamber (5) passes through the cooling The agent water pump (18) is connected to the sprinkler located on the upper part of the evaporative freezing chamber (5), and the ice-forming device (6) is arranged at the lower part of the shower, and the ice-water separation device (7) is arranged at the lower part of the ice-forming device (6). ). 3. A method for producing liquid ice based on a lithium bromide absorption refrigeration cycle based liquid ice production device as claimed in claim 1, characterized in that, in the evaporation ice making process, the water supply device (3) is based on the evaporation The minimum water level in the freezer (5) requires automatic replenishment of water into the evaporative freezer (5). During the replenishment process, the normal temperature water in the water replenishment device (3) enters the evaporative freezer after being throttled and reduced by the water replenishment throttle valve (22) In (5), the water in the condenser enters the evaporative freezing chamber (5) through the throttle valve (4), and the ice-water mixture formed on the ice-forming device (6) in the evaporative freezing chamber (5) passes through the ice-water separation device (7 ), the first one-way valve (12), the middle ice storage chamber (8), and the second one-way valve (13) enter the ice storage tank (9) to complete the ice making process. 4. The method for producing liquid ice based on the liquid ice production device of the lithium bromide absorption refrigeration cycle according to claim 3, characterized in that the method utilizes the concentrated solution in the absorber (10) to absorb and evaporate the freezing chamber The steam in (5) creates a low-pressure environment for the evaporative freezer (5), in which water evaporates to absorb its own heat, and grows into liquid ice on the ice-forming device (6). 5. according to claim 3 the manufacture of the liquid ice production device based on lithium bromide absorption refrigeration cycle The method for taking liquid ice is characterized in that the ice-water separation process of the method is formed on the ice-forming device (6). The ice crystals are separated by the ice-water separation device (7), and kept in the intermediate ice storage (8) and in the evaporative freezer At the same pressure, open the one-way valve (12), the ice crystals enter the intermediate ice storage (8) under the action of gravity, then close the first one-way valve (12), open the second one-way valve (13) and the ice crystals enter The ice storage tank completes the ice-water separation process; after the ice-water separation is completed, the intermediate ice storage (8) is evacuated by a vacuum pump.

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