Dry ice forming method and ice making equipment for implementing the method

Abstract

The present invention discloses a dry ice forming method and ice-making equipment for implementing the method. The dry ice forming method first applies liquid ethanol to the inner surface of a mold cavity by spraying, coating, or rubbing. Liquid carbon dioxide is then sprayed into the mold cavity, where the carbon dioxide accumulates in the mold cavity in the form of snowflakes. A hydraulic cylinder mechanism is then activated to compact the carbon dioxide in the mold cavity to form dry ice blocks. Finally, the dry ice is removed from the mold cavity. Applying liquid ethanol to the inner wall of the mold cavity improves the smoothness of the dry ice side surface, reduces the volatile area of ​​the dry ice surface, and achieves uniform stress within the dry ice, thereby increasing its strength and density. Furthermore, the friction between the dry ice blocks and the mold cavity is reduced, thereby enhancing the compaction force on the dry ice.

Description

Technical Field

[0001] The invention relates to a dry ice forming method and ice making equipment for implementing the method. Background Art

[0002] Dry ice is solid carbon dioxide, capable of reaching temperatures exceeding -70°C, making it an excellent refrigeration material. However, dry ice readily absorbs heat and vaporizes, volatile. Therefore, dry ice must be immediately stored in insulated containers after production. While insulated containers can be used to maintain heat during transportation, their high volatility makes them impractical for long-distance transportation, such as exporting them internationally.

[0003] In summary, how to reduce the volatilization rate of dry ice and extend the transportation time of dry ice is a technical problem that technicians in this field have been seeking to overcome. Summary of the Invention

[0004] The present invention provides a dry ice forming method and an ice making device for implementing the method, which overcomes the shortcomings of the background art. The technical solution adopted by the present invention to solve the technical problem is:

[0005] The dry ice forming method first applies liquid ethanol to the inner surface of the mold cavity by spraying, coating or rubbing, and then sprays liquid carbon dioxide into the mold cavity. The carbon dioxide accumulates in the mold cavity in the shape of snowflakes. Then, the hydraulic cylinder mechanism is activated to compact the snowflake-shaped carbon dioxide in the mold cavity to form block dry ice, and finally the block dry ice is removed from the mold cavity.

[0006] Before pressing the dry ice, liquid ethanol is applied to the inner surface of the mold cavity. During the pressing process, the liquid ethanol on the outer surface of the dry ice and the inner surface of the mold cavity forms a thin, viscous layer under the high pressure of the hydraulic cylinder mechanism. This significantly improves the smoothness of the dry ice's side surface, effectively reducing the surface area for evaporation and slowing its evaporation rate. Furthermore, due to the smooth surface of the dry ice, the friction between the dry ice and the mold cavity surface is significantly reduced during the pressing process. The pressure applied to the dry ice is very uniform, resulting in uniform stress within the dry ice and preventing it from fracturing. This increases the ultimate pressure that the dry ice can withstand, which in turn increases the pressure of the hydraulic cylinder mechanism, thereby enhancing its strength and density. This increases the dry ice's density ratio and effectively reduces its evaporation rate. Furthermore, the smoother the dry ice surface, the easier it is to demold. After demolding, the liquid ethanol on the dry ice surface naturally evaporates after absorbing heat, without polluting the environment. The heat is partially absorbed by the liquid ethanol, which also helps to slow the evaporation rate of the dry ice.

[0007] In a preferred embodiment, the mold cavity is a straight through channel, and the hydraulic cylinder mechanism squeezes the dry ice in the mold cavity from both sides. This compresses both sides of the dry ice, increases its strength, and prolongs its volatilization time.

[0008] In a preferred embodiment, the mold cavity is placed vertically, thereby facilitating demoulding.

[0009] In a preferred embodiment, an exhaust pipe is connected to the mold cavity, and liquid carbon dioxide is sprayed into the mold cavity from the top of the exhaust pipe. This facilitates exhaust during the pressing process and improves the tightness of the dry ice.

[0010] In a preferred embodiment, an ethanol injection nozzle is provided on the upper portion of the inner wall of the mold cavity, thereby enabling automatic injection of liquid ethanol and facilitating automation.

[0011] In a preferred embodiment, the ethanol injection nozzle injects liquid ethanol obliquely downward.

[0012] In a preferred embodiment, the dry ice is pushed out of the mold cavity by means of a hydraulic cylinder mechanism.

[0013] In a preferred embodiment: the pressure of the hydraulic cylinder mechanism is ≥25MPa.

[0014] The ice-making equipment includes a mold base, which is provided with a vertically penetrating mold cavity and a two-hydraulic cylinder mechanism capable of respectively squeezing the material in the mold cavity from the upper and lower sides of the mold cavity. The mold base is provided with a nozzle for spraying liquid ethanol on the upper part of the inner wall of the mold cavity.

[0015] A nozzle is installed inside the mold cavity, connected to an ethanol bottle via a pipe. Liquid ethanol is then sprayed onto the mold cavity's inner surface. Snowflake-shaped dry ice is then added to the cavity, and finally, a hydraulic cylinder mechanism squeezes the material toward each other to form a block of dry ice. This not only improves the smoothness of the block's side surface and reduces the surface area for evaporation, but also creates uniform stress within the dry ice, enhancing its strength and facilitating demolding.

[0016] A preferred embodiment further includes an exhaust pipe connected to the mold cavity. A copper filter formed by powder metallurgy sintering is installed on the sidewall of the exhaust pipe. A carbon dioxide inlet is provided above the copper filter. This facilitates exhaust from the mold cavity and improves the tightness of the dry ice. DETAILED DESCRIPTION

[0017] The dry ice forming method involves spraying, coating, or rubbing liquid ethanol onto the inner surface of the mold cavity. An ice machine then sprays liquid carbon dioxide into the mold cavity, causing the carbon dioxide dry ice to accumulate in the form of snowflakes. A hydraulic cylinder is then activated to compact the snowflakes into blocks, which are then removed from the mold. The temperature change caused by the liquid carbon dioxide spraying into the mold creates the snowflake-shaped dry ice.

[0018] Preferably, the mold cavity is a straight through channel, and the hydraulic cylinder mechanism squeezes the dry ice within the mold cavity from opposite sides. The mold cavity is positioned vertically, with the two hydraulic cylinder mechanisms squeezing the dry ice from the top and bottom, respectively. Furthermore, after the dry ice is formed, the hydraulic cylinder mechanism can be used to push it out from the bottom of the mold cavity, facilitating automatic demolding.

[0019] Preferably, an exhaust pipe is connected above the mold cavity, and liquid carbon dioxide is sprayed into the mold cavity from the top of the exhaust pipe. The front part of the extrusion process is conducive to the exhaust of gas.

[0020] Preferably, an ethanol injection nozzle is provided on the upper portion of the inner wall of the mold cavity to automatically inject liquid ethanol. The ethanol injection nozzle injects liquid ethanol obliquely downward, which is conducive to filling the mold cavity.

[0021] The pressure of the hydraulic cylinder mechanism is ≥25MPa, and can be increased to 27MPa, or even 30MPa.

[0022] The ice-making equipment used to implement the above-mentioned forming method includes a mold base, which is provided with a vertically penetrating mold cavity, and also includes two hydraulic cylinder mechanisms that can squeeze the material in the mold cavity from the upper and lower sides of the mold cavity respectively. The mold base is provided with a nozzle for spraying liquid ethanol on the upper part of the inner wall of the mold cavity.

[0023] During production, the nozzle sprays liquid ethanol, coating the inner surface of the mold cavity. Then, the mold cavity is filled with carbon dioxide in the form of snowflakes. Finally, two hydraulic cylinders move in opposite directions to compact the material in the mold cavity to form dry ice. Those skilled in the art will recognize that using hydraulic cylinders to compact the material in the mold cavity to form dry ice is a traditional dry ice production process.

[0024] Preferably, the method further comprises an exhaust pipe connected to the mold cavity, wherein a copper filter formed by powder metallurgy sintering is provided on the side wall of the exhaust pipe, and a carbon dioxide feed port is provided above the copper filter. Hydraulic carbon dioxide is injected into the mold cavity and the exhaust pipe through the carbon dioxide feed port and accumulates in a snowflake-like manner.

[0025] The above description is merely a preferred embodiment of the present invention and therefore cannot be used to limit the scope of the present invention. In other words, equivalent changes and modifications made according to the scope of the present invention and the contents of the specification should still fall within the scope of the present invention.

Claims

1. Dry ice forming method, characterized in that: First, liquid ethanol is applied to the inner surface of the mold cavity by spraying, coating or rubbing, and then liquid carbon dioxide is sprayed into the mold cavity. The carbon dioxide accumulates in the mold cavity in the shape of snowflakes. Then, the hydraulic cylinder mechanism is started to compact the snowflake-shaped carbon dioxide in the mold cavity to form block dry ice, and finally the block dry ice is taken out from the mold cavity.

2. The dry ice forming method according to claim 1, wherein: The mold cavity is a straight through channel, and the hydraulic cylinder mechanism squeezes the dry ice in the mold cavity from both sides of the mold cavity.

3. The dry ice forming method according to claim 2, wherein: The mold cavity is placed vertically.

4. The dry ice forming method according to claim 3, wherein: An exhaust pipe is connected above the mold cavity, and liquid carbon dioxide is sprayed into the mold cavity from the top of the exhaust pipe.

5. The dry ice forming method according to claim 3, wherein: An ethanol injection nozzle is arranged on the upper portion of the inner wall of the mold cavity.

6. The dry ice forming method according to claim 5, wherein: The ethanol injection nozzle injects liquid ethanol obliquely downward.

7. The dry ice forming method according to claim 1 or 2, characterized in that: The dry ice is pushed out of the mold cavity with the help of a hydraulic cylinder mechanism.

8. The dry ice forming method according to claim 1, wherein: The pressure of the hydraulic cylinder mechanism is ≥25MPa.