WO2020191449A1

WO2020191449A1 - Enhanced coolant

Info

Publication number: WO2020191449A1
Application number: PCT/AU2020/050295
Authority: WO
Inventors: Craig Nicol; David Pope; Ashok Nanjundan; Roberto Bran
Original assignee: Graphene Manufacturing Australia Pty Ltd
Priority date: 2019-03-27
Filing date: 2020-03-27
Publication date: 2020-10-01

Abstract

The present invention relates to a method for producing an enhanced coolant. The method includes combining graphene with one or more dispersing agents to form a combination. The method further involves mixing the combination with one or more coolant compositions. In certain embodiments the enhanced coolant may provide an increased heat transfer rate and subsequent reduction in cooling time up to 48% over existing coolants.

Description

ENHANCED COOLANT

TECHNICAL FIELD

[0001] The present invention relates to an enhanced coolant. The present invention has particular, although not exclusive application to coolants for heat exchanger.

BACKGROUND

[0002] The reference to any prior art in this specification is not, and should not be taken as an acknowledgement or any form of suggestion that the prior art forms part of the common general knowledge.

[0003] A heat exchanger is a device used to transfer heat between two or more fluids. Heat exchangers are used in both cooling and heating processes. The fluids may be separated by a solid wall to prevent mixing or they may be in direct contact.

[0004] An example of a heat exchanger is found in an internal combustion engine in which a circulating fluid, known as a coolant, flows through radiator coils and air flows past the coils, which cools the coolant and heats the incoming air.

[0005] A coolant is a substance, typically gas, liquid and/or solid (two-phase), that is used to reduce or regulate the temperature of a system. An ideal coolant has high thermal capacity, low viscosity, is low-cost, non-toxic, chemically inert and neither causes nor promotes corrosion of the cooling system.

[0006] The coolant can either keep its phase and stay liquid or gaseous, and/or can undergo a phase transition, with the latent heat adding to the cooling efficiency. The latter, when used to achieve below-ambient temperature, is more commonly known as refrigerant.

[0007] The preferred embodiment provides an enhanced coolant over known coolants. SUMMARY OF THE INVENTION

[0008] According to one aspect of the present invention, there is provided a method for producing an enhanced coolant, the method including:

combining nanostructured graphene with one or more dispersing agents to form a combination; and

mixing the combination with one or more coolant compositions.

[0009] In certain embodiments, the enhanced coolant may provide an increased heat transfer rate and subsequent reduction in cooling time up to 48% over existing coolants. Preferably, the graphene is in the form of graphene nano-particles and/or flakes added to said dispersing agents. The graphene nanostructures may be manufactured from carbon gas, thereby being added in significantly lesser quantity (typically up to 100 times) than graphene otherwise manufactured from graphite to obtain a comparable result. The combination may include graphene dosage rates as low as 0.001% up to 3.0%, by weight for ready to use and concentrate products. The graphene nanostructures may be in the form of particles or platelets or flakes in the range of 2nm to 800nm.

[00010] The mixing process may involve mixing with a high shear mixer, with shear rates ranging from a minimum of 1/10,000 per second, to disperse and distribute the graphene nanostructures. The mixing times may range from 9 minutes to 72 hours, dependent upon varying dispersion and distribution combinations.

[00011] The coolant compositions may include one or more coolants and water. The method may involve adding water. The water dosages may be from 0% up to 100%, by weight. The coolant compositions may consist of one or more coolants. The coolants may include any glycol based coolant - including one or more of Ethylene Glycol, Propylene Glycol and Glycerin.

[00012] The dispersing agents may include any one or more or a combination of a surfactant based dispersant, Sodium dodecyl sulphate (SDS), Cetyl trimethyl ammonium bromide (CTAB), Sodium deoxycholate (DOC) and Sodium dodecyl benzene sulphonate. The dispersing agents may include any one or more of a cellulose based dispersant, Ethyl cellulose, Carboxy methyl cellulose (sodium salts included), and Dihydrolevoglucosenone. The dispersing agents may include a Polyaromatic Hydrocarbon based dispersant, such as Pyrene sulfonic acid sodium salt. The dispersing agents may include a Polymer based dispersant such as Polyvinyl pyrrolidone (PVP). The dispersing agents may include any one or more of a

commercially available dispersant, DYSPERBYK 194N, DYSPERBYK 192,

DYSPERBYK 199, DYSPERBYK 2013, DYSPERBYK 2015 and non-ionic surfactants such as Triton X-100, Brij L23, BrijOI O, Tween 20, ETHOQUAD and Adogen.

[00013] According to one aspect of the present invention, there is provided an enhanced coolant produced in accordance with the method.

[00014] According to one aspect of the present invention, there is provided a manufacturing system for manufacturing an enhanced coolant, the system including: combining means for combining graphene with one or more dispersing agents to form a combination; and

mixing means for mixing the combination with one or more coolant compositions.

[00015] Any of the features described herein can be combined in any combination with any one or more of the other features described herein within the scope of the invention.

Preferred features, embodiments and variations of the invention may be discerned from the following Detailed Description which provides sufficient information for those skilled in the art to perform the invention. The Detailed Description is not to be regarded as limiting the scope of the preceding Summary of the Invention in any way.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[00016] According to an embodiment of the present invention, there is provided a method for producing an enhanced coolant. The method includes adding graphene nanostructures into one or more dispersing agents to form a combination. The resultant combination is then high-shear mixed with one or more coolant compositions to form the graphene-enhanced coolant.

[00017] The graphene nanostructures are pre-manufactured from gases containing Carbon, thereby being added in significantly lesser quantity (typically up to 100 times) than graphene otherwise manufactured from graphite to obtain a comparable result.

[00018] The combination includes graphene dosage rates as low as 0.01 % up to 1.0%, by weight. The graphene nano-particles are in the form of platelets in the range of 50nm to 200nm.

[00019] The mixing process may involve mixing with a high shear mixer. The high- shear mixing is a process whereby fluid undergoes shear when one area of fluid travels with a different velocity relative to an adjacent area. This velocity difference creates the shear; wherein shear rates range from a minimum of 1/10,000 per second and disperse and distribute the graphene nano-particles. The mixing times range from 9 minutes to 72 hours, dependent upon varying dispersion and distribution combinations required.

[00020] The coolant compositions can include one or more coolants and water. The method may involve adding water as required. The water dosages range from 0% up to 100%, by weight. The coolants but not limited to Mono Ethylene Glycol, Propylene Glycol and glycerol.

[00021] The dispersing agents can include any one or more of a surfactant based dispersant; namely: Sodium dodecyl sulphate (SDS), Cetyl trimethyl ammonium bromide (CTAB), Sodium deoxycholate (DOC) and Sodium dodecyl benzene

sulphonate. [00022] The dispersing agents can include any one or more of a cellulose based dispersants, namely whether Ethyl cellulose, Carboxy methyl cellulose (sodium salts included), and Dihydrolevoglucosenone.

[00023] The dispersing agents can include a Polyaromatic Hydrocarbon based dispersant, such as a sodium salt of Pyrene sulfonic acid.

[00024] The dispersing agents can include a Polymer based dispersant, such as Polyvinyl pyrrolidone (PVP).

[00025] The dispersing agents can include any one or more of a commercially available dispersant, including but not limited to DYSPERBYK 194N, DYSPERBYK 192, DYSPERBYK 199, DYSPERBYK 2013, DYSPERBYK 2015 and non-ionic surfactants such as Triton X-100, Brij L23, BrijOI O, Tween 20, ETHOQUAD and Adogen.

[00026] The enhanced coolant is suitable for use in heat transfer cooling processes including but not limited to:

• Heating, Ventilation, Air Conditioning (HVAC) systems;

• Industrial Process cooling systems;

• Automotive internal combustion petrol and diesel engine cooling system;

including passenger car, motor bike, commercial vehicle, truck (rigid and flexible), bus and other vehicles;

• Electrical vehicles;

• Stationary power systems (including gas turbines, diesel power generators,

petrol power generators and other stationary power systems);

• Aerospace (including any airplane, satellite and space rockets); and

• Electrical distribution grid storage system.

[00027] A manufacturing system is also provided for manufacturing the enhanced coolant. The system includes combining means for combining the graphene nano particles with one or more dispersing agents to form a combination. The system further includes mixing means for mixing the combination with one or more coolant

compositions. [00028] A person skilled in the art will appreciate that many embodiments and variations can be made without departing from the ambit of the present invention.

[00029] In one embodiment, each coolant composition consists of one or more coolants only, and no added water.

[00030] In compliance with the statute, the invention has been described in language more or less specific to structural or methodical features. It is to be understood that the invention is not limited to specific features shown or described since the means herein described comprises preferred forms of putting the invention into effect.

[00031] Reference throughout this specification to‘one embodiment’ or‘an embodiment’ means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearance of the phrases‘in one embodiment’ or‘in an embodiment’ in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more combinations.

Claims

The claims defining the invention are as follows:

1. A method for producing an enhanced coolant, the method including:

combining graphene with one or more dispersing agents to form a combination; and

mixing the combination with one or more coolant compositions.

2. A method as claimed in claim 1 , wherein the graphene is in the form of graphene nano-particles added to said dispersing agents.

3. A method as claimed in claim 2, wherein the graphene nanostructures are manufactured from carbon containing gases, thereby being added in significantly lesser quantity than graphene otherwise manufactured from graphite to obtain a comparable result.

4. A method as claimed in claim 2, wherein the graphene nano-particles are in the form or platelets in the range of 2nm to 800nm.

5. A method as claimed in claim 1 , wherein the combination includes graphene dosage rates as low as 0.001 % up to 3.0%, by weight.

6. A method as claimed in claim 1 , wherein the mixing involves mixing with a high shear mixer, with shear rates ranging from a minimum of 1/10,000 per second, to disperse and distribute the graphene particles.

7. A method as claimed in claim 1 , wherein the mixing involves mixing times ranging from 9 minutes to 72 hours, dependent upon varying dispersion and distribution combinations.

8. A method as claimed in claim 1 , wherein the coolant compositions include one or more coolants and water.

9. A method as claimed in claim 1 , involving adding water.

10. A method as claimed in claim 9, wherein the water dosages are from 0% up to 100%, by weight.

1 1. A method as claimed in claim 1 , wherein the coolant compositions consist of one or more coolants only.

12. A method as claimed in claim 1 1 , wherein the glycol based coolants include any one or more of Mono Ethylene Glycol, Propylene Glycol and glycerol.

13. A method as claimed in claim 1 , wherein the dispersing agents include any one or more of: a surfactant based dispersement, Sodium dodecyl sulphate (SDS), Cetyl trimethyl ammonium bromide (CTAB), Sodium deoxycholate (DOC) and Sodium dodecyl benzene sulphonate.

14. A method as claimed in claim 1 , wherein the dispersing agents include any one or more of: a cellulose based dispersants, Ethyl cellulose, Carboxy methyl cellulose, and Dihydrolevoglucosenone.

15. A method as claimed in claim 1 , wherein the dispersing agents include a

Polyaromatic Hydrocarbon based dispersant, such as Pyrene sulfonic acid.

16. A method as claimed in claim 1 , wherein the dispersing agents include a Polymer based dispersant such as Polyvinyl pyrrolidone (PVP).

17. A method as claimed in claim 1 , wherein the dispersing agents include any one or more of a commercially available dispersant, including but not limited DYSPERBYK 194N, DYSPERBYK 192, DYSPERBYK 199, DYSPERBYK 2013, DYSPERBYK 2015 and non-ionic surfactants such as Triton X-100, Brij L23, BrijOI O, Tween 20,

ETHOQUAD and Adogen.

18. An enhanced coolant produced in accordance with the method as claimed in claim 1.

19. A manufacturing system for manufacturing an enhanced coolant, the system including:

combining means for combining graphene with one or more dispersing agents to form a combination; and

mixing means for mixing the combination with one or more coolant compositions.

20. A manufacturing system as claimed in claim 19, further including means for producing the graphene in the form of graphene nano-particles combined with said dispersing agents.