WO2011121616A2

WO2011121616A2 - Rapid cooling system for cooling liquids

Info

Publication number: WO2011121616A2
Application number: PCT/IN2011/000237
Authority: WO
Inventors: Sorin Grama; Ethan Edward Pease; Samuel Saul White; Matthew Dorson; Anthony Joshua; Robert Shydo; Eric Smith; Jacob Riddley Felser
Original assignee: Promethean Power Systems
Priority date: 2010-03-31
Filing date: 2011-03-28
Publication date: 2011-10-06
Also published as: WO2011121616A3

Abstract

The present invention provides a rapid cooling system for cooling liquids. The system includes a double-jacketed tube having an outer layer and an inner layer. The outer layer is capped by an outer dome and the inner layer tapered to create an inner dome which is configured with an outlet. Further, the system includes a helical member configured between the outer layer and the inner layer for guiding a cooling medium entering through an inlet to flow in a counter- flow direction around the helical coil to move upwards. The cooling medium moves between the helical space created by the helical member. Furthermore, the system includes a funnel disposed over the double- jacketed tubes. The funnel is capable of directing a liquid to be cooled to flow down by gravity over the outer dome and the outer layer in a form of a thin film. The liquid to be cooled exchanges heat with the cooling medium flowing through the double jacketed tube.

Description

Rapid Cooling System for Cooling Liquids

Field of invention

The present invention relates to a rapid cooling system for cooling liquids, and more particularly, to a rapid cooling system for cool ing raw m i lk.

Background of the invention Preserving and storing food items such as raw mi lk requires cooling to temperatures below 5° C. Furthermore, rapidly cool ing the m ilk to a temperature of about 10 ⁰ C first slows down bacterial growth sign ificantly and contributes to a much greater milk quality. If the milk is cooled immediately after it has been milked, its taste and quality can be preserved until further processing.

Cool i ng l iq u ids such as the m i l k requ ires a heat exchanger to transfer energy from a cold fluid medium to the milk. The cold flu id medium is typically a l iquid such as water, a water-glycol m ixture, a water-alcohol m ixture or any other mixture that lowers the freezing point of water. As the water-alcohol mixture (cold flu id) and the milk (hot fluid) cannot be m ixed, they are arranged to flow on two different sides of a heat exchanging barrier. As the two fluids flow past each other, they exchange energy. In this process of heat exchange, the hot fl uid cools down while the cold flu id warms up. Various im plementations of such a heat exchanging mechanism are in use today.

Rapid cool ing devices for milk and other liquid food products are generally found in large industrial processing plants where these liquids are cooled immediately using san itary heat exchangers. These specialized heat exchangers are designed to work at very h igh flow rates and must be disassembled period ically to al low for cleaning in order to maintain the sanitary conditions. Because of this, the sanitary heat exchangers are expensive and difficult to operate. Furthermore, the heat exchangers of this nature are designed for large volumes and therefore consume large amounts of power for pumping the liquids. As such, these heat exchangers cannot be used in home or small commercial applications where flow rates are much smaller and available power is much less.

The known art in the field of rapid cooling devices falls into following two broad categories

1. Flat Plate Heat Exchangers: The flat plate heat exchangers are designed using a plurality of flat plates stacked up and sealed using a frame. The hot and cold fluids flow in a zigzag pattern on opposite sides of each plate. These heat exchangers are efficient at transferring energy from the cold fluid to the hot fluid. However, to maintain sanitary conditions, the flat plates are to be periodically removed and scrubbed to remove any residues that may cause bacterial growth. Further, these heat exchangers are expensive and difficult to maintain and can only be found in large cooling installation such as dairy processing plants.

Variations in the flat plate heat exchanger model include shell-in-tube heat exchangers which have same drawbacks and are expensive and difficult to clean.

2. Conventional Falling Film Heat Exchangers: The conventional falling film heat exchangers are an improvement on the flat-plate heat exchangers to allow for easier cleaning and sanitation. Falling film heat exchangers of the prior art use a two-phase refrigerant gas-liquid as the cooling medium. The refrigerant liquid (such as R-22) expands into gas inside a set of two flat plates sandwiched together while the liquid to be cooled (such as milk) flows as a thin film on the outside the flat plates.. Design of the fall ing film heat exchangers of the prior art , cannot be scaled to small applications that require lower flow rates, is not energy efficient as it requires large compressor power and does not implement counter-flow heat exchanging mechanism because it uses expanding refrigerant gas instead of a flowing l iquid cooling medium.

Objects of the invention

An object of the present invention is to provide an energy efficient, rapid cooling system for l iquids.

Another object of the present invention is to provide a rapid cooling system which is easy to clean and maintains sanitary conditions.

Yet another object of the present invention is to provide a rapid cool ing system which simple in construction and can be adapted to small-scale appl ications requiring minimal pumping power

Summary of the invention

Accord ingly the present invention provides a rapid cooling system for cool ing l iqu ids, the system com prising:

a double-jacketed tube having an outer layer and an inner layer, the outer layer capped by an outer dome and the inner layer capped by an inner dome, the inner dome configured with an outlet,

a hel ical member configured between the outer layer and the inner layer, the helical member providing a helical space between the outer layer and the inner layer for guiding a cooling medium entering through an inlet to flow in a counter- flow direction and to move upwards thereby covering the inner surface of the outer layer and the outer dome, thereafter the cooling medium exit through the outlet of the i nner layer; a funnel disposed over the double-jacketed tubes, the funnel capable of directing a l iquid to be cooled to flow down by gravity over the outer dome and the outer layer in a form of a thin film, wherein the liquid to be cooled exchanges heat with the cool ing medium flowing through the double jacketed tube; and

a bottom tray for col lecting the cooled l iquid from the sides of the outer layer.

Typically, wherein the outer layer and outer dome is made of stainless steel.

Typically, wherein the inner layer and inner dome is made from any one of plastic and stainless steel.

Typically, wherein the cooling medium is a liquid comprising of any one of the water, water-glycol m ixture or water-alcohol mixture

Typically, wherein the liquid to be cooled is m ilk.

Brief description of the drawings

Figure 1 illustrates the schematic diagram of a rapid cooling system for cooling l iquids in accordance with the present invention; and

Figure 2 illustrates the partial sectional view of the rapid cooling system for cooling liquids in accordance with the present invention.

Detailed description of the invention

The foregoing objects of the present invention are accompl ished and the problems and shortcomings associated with the prior art, techniques and approaches are overcome by the present invention as described below in the preferred embodiment. Accordingly, the present invention provides a rapid cooling system (hereinafter referred as the 'system') for cooling liquids in accordance with the present invention. The system is energy efficient. Further, the system is easy to clean and maintains sanitary conditions. Furthermore, the system is simple in construction and can be scaled to small applications.

The present invention is illustrated with reference to the accompanying drawings, throughout which reference numbers indicate corresponding parts in the various figures. These reference numbers are shown in bracket in the following description.

Referring now to figure 1 and 2. there is shown a rapid cooling system for cooling liquids in accordance with the present invention. Specifically, the figure 1 and 2, shows the system (100). The system (100) includes a double-jacketed tube (10), a helical coil (20). a funnel (30) and a bottom tray (40).

The double-jacketed tube (10) includes an outer layer (12) and an inner layer (14). Specifically, the outer layer (12) is capped by an outer dome (16) and the inner layer is tapered to create an inner dome (18) which is configured with an outlet (19). Specifically, the inner layer (14) and the inner dome (18) follow the shape of the outer layer and outer dome.

In an embodiment, the outer layer (12) is made of stainless steel and the inner layer (14) is made of material selected from group consisting of plastic and stainless steel. The outer layer (12) and the inner layer (14) include the helical member (20) therebetween.

Specifically, a helical member (20) is configured between the outer layer (12) and the inner layer (14). The helical member (20) provides a helical space for guiding a cooling medium entering through an inlet (22) to flow in a counter-flow direction. The cooling medium moves upwards thereby uniformly covering the inner surface of the outer layer (12) and outer dome (16). Further, the cooling medium exits through the outlet (19).

In accordance with the present invention, the helical space is created by a helical member (20) wrapped around the inner layer (14) in between the inner layer (14) and the outer layer (12). However, it may be evident to those skilled in the art that the helical space can be created by any other means such as shaping or molding of the inner layer (14). Specifically, the helical space through which the cold medium flows is delineated by a helical member wrapped around the around the inner layer (14) in between the inner layer (14) and the outer layer (12).

In an embodiment, the cooling medium is any one of the water, water-glycol mixture and water-alcohol mixture. However, it may be evident to those skilled in the art that any other liquid cooling medium may be used.

Further, the funnel (30) is disposed over the double-jacketed tube (10). Specifically, the funnel (30) is positioned above the outer dome (16). The funnel (30) is capable of directing a liquid to be cooled to flow down by gravity over the outer dome (16) and the outer layer (12) in a form of a thin film. The liquid to be cooled exchanges heat with the cooling medium flowing through the double jacketed tube (10). In an embodiment, the liquid to be cooled is milk. However, it may be evident to those skilled in the art that any other liquids other than milk may be cooled using the system of the present invention.

The liquid to be cooled is dispensed from a funnel (30) through a calibrated spout (50) located above the outer dome (16). The diameter of the spout (32) determines the flow rate while the length of the spout (32) ensures a constant flow rate during operation. The bottom tray (40) collects the cooled liquid from the sides of the outer layer (12).

The system of the present invention is designed to work with low volumes of milk and uses the power of gravity to move the milk in order to reduce electrical power consumption.

Further, to maintain sanitary condition, only the outer dome ( 1 6) and the outside of outer layer (12) of the system ( 100) need to be cleaned. These two surfaces are the only surfaces that the liquid to be cooled touches during the heat exchanging process. These two surfaces are easily accessed and visible to an operator.

An important aspect the present invention is that the liquid to be cooled flows without any restrictions over the outer dome ( 16) and the outer layer ( 12) by force of gravity. Furthermore, the liquid to be cooled spreads into a thin-film over the heat exchanging surface thus enhancing the heat transfer and ensuring a rapid cooling.

Furthermore, rapid cooling performance of the system ( 100) depends on the liquid flow rate over the heat exchanging surface. The diameter of the spout (32) determines the flow rate while the length of the spout (32) ensures a constant flow rate during operation.

The system according to present invention is designed to cool lower amounts of liquid quickly using only a small amount of electrical power. Further, the system is designed to operate easily and can be cleaned by a single operator after each use, thus maintaining optimal sanitary conditions. The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the present invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teach ing. The em bod iments were chosen and described i n order to best explain the principles of the present invention and its practical application, to thereby enable others skilled in the art to best utilize the present invention and various embodiments with various modifications as are suited to the particular use contemplated. It is understood that various om ission and substitutions of equivalents are contemplated as c ircumstance may suggest or render expedient, but such are intended to cover the appl ication or implementation without departing from the spirit or scope of the present invention.

Claims

We Claim

1 . A rapid cool ing system for cooling liquids, the system comprising:

a hel ical mem ber configured between the outer layer and the inner layer, the helical member providing a helical space between the outer layer and the inner layer for guid ing a liqu id cooling medium entering through an inlet to flow in a counter-flow direction and to move upwards thereby covering the inner surface of the outer layer and the outer dome, thereafter the cooling medium exit through the outlet of the inner layer;

a funnel disposed over the double-jacketed tubes, the funnel capable of directing a l iquid to be cooled to flow down by gravity over the outer dome and the outer layer in a form of a thin fi lm, wherein the liqu id to be cooled exchanges heat with the cool i ng med i um flowing through the double jacketed tube; and

a bottom tray for col lecting the cooled liquid from the sides of the outer layer.

2. The system as clai med i n clai m 1 , wherein the outer layer and the outer dome is made of stainless steel .

3. The system as claimed in claim 1 , wherein the inner layer and the inner dome is made of material selected from group consisting of plastic and stainless steel .

4. The system as claimed in claim 1 , wherein the cool ing med ium is any one selected from group consisting of water, water-glycol mixture, water-alcohol mixture or any other liquid cooling medium .

5. The system as claimed in claim 1 , wherein the liquid to be cooled is milk.