U.S. patent application number 14/921339 was filed with the patent office on 2016-02-18 for low gwp heat transfer compositions containing difluoromethane, a fluorinated ethane and 1,3,3,3-tetrafluoropropene.
The applicant listed for this patent is HONEYWELL INTERNATIONAL INC.. Invention is credited to Christopher J. Seeton, Mark W. Spatz, Samuel F. Yana Motta.
Application Number | 20160046850 14/921339 |
Document ID | / |
Family ID | 47506795 |
Filed Date | 2016-02-18 |
United States Patent
Application |
20160046850 |
Kind Code |
A1 |
Yana Motta; Samuel F. ; et
al. |
February 18, 2016 |
LOW GWP HEAT TRANSFER COMPOSITIONS CONTAINING DIFLUOROMETHANE, A
FLUORINATED ETHANE AND 1,3,3,3-TETRAFLUOROPROPENE
Abstract
Heat transfer compositions, methods and use wherein the
composition comprising: (a) from about 5 to about 20% by weight of
HFC-32; (b) from about 70% to about 90% by weight of HFI-1234ze;
and (c) from about 5% to less than about 20% by weight of HFC-152a
and/or HFC-134a.
Inventors: |
Yana Motta; Samuel F.; (East
Amherst, NY) ; Spatz; Mark W.; (East Amherst, NY)
; Seeton; Christopher J.; (East Amherst, NY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
HONEYWELL INTERNATIONAL INC. |
MORRIS PLAINS |
NJ |
US |
|
|
Family ID: |
47506795 |
Appl. No.: |
14/921339 |
Filed: |
October 23, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13530585 |
Jun 22, 2012 |
9169427 |
|
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14921339 |
|
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61507185 |
Jul 13, 2011 |
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Current U.S.
Class: |
252/67 |
Current CPC
Class: |
C09K 5/045 20130101;
C09K 2205/126 20130101; C09K 2205/22 20130101; C09K 2205/122
20130101 |
International
Class: |
C09K 5/04 20060101
C09K005/04 |
Claims
1. A heat transfer composition comprising: (a) HFO-1234ze; (b)
HFC-32; and (c) HFC-152a, the amount of HFC-152a present in the
composition being less than about 20% by weight of the composition
and not less than about 5% of the composition.
2. The heat transfer composition of claim 1 wherein said
composition has a GWP of not greater than 150.
3. The heat transfer composition of claim 1 wherein said
composition has a GWP of not greater than 100.
4. The heat transfer composition of claim 1 wherein said
composition has a hazard value of less than about 7.
5. The heat transfer composition of claim 1 wherein said
composition has a hazard value of less than about 4.
6. The heat transfer composition of claim 1 wherein said
composition has a hazard value of not greater than about 2.
7. The heat transfer composition of claim 1 wherein said
composition has a burning velocity of less than 10.
8. The heat transfer composition of claim 1 wherein said
composition has a capacity relative to HFC-134a under MAC
conditions of from about 90% to about 105%.
9. The heat transfer composition of claim 1 wherein said
composition has a capacity relative to HFC-134a under MAC
conditions of from about 95% to about 101%.
10. The heat transfer composition of claim 1 wherein said
composition has a COP relative to HFC134a under MAC conditions of
from about 98% to about 102%.
11. The heat transfer composition of claim 1 wherein said
composition has a COP relative to HFC134a under MAC conditions of
from about 100%.
12. The heat transfer composition of claim 1 wherein said
composition comprises from about 70% to about 90% by weight of
HFO-1234ze.
13. The heat transfer composition of claim 12 wherein said
HFO-1234ze consists essentially of trans-HFO1234ze.
14. The heat transfer composition of claim 1 wherein said
composition comprises from about 5% to about 20% by weight of
HFC-32.
15. The heat transfer composition of claim 1 wherein said
composition further comprises HFC-134a in an amount of up to about
6% by weight.
16. The heat transfer composition of claim 1 wherein said HFC-152a
is present in the composition in an amount of not greater than
about 15% by weight.
17. The heat transfer composition of claim 1 wherein HFO-1234ze is
provided in an amount between about 75% and about 79% by weight,
HFC-152a is provided in an amount of about 15% by weight and HFC-32
is provided in an amount between about 6% and about 10% by
weight.
18. An air conditioning system comprising a heat transfer
composition according to claim 1.
19. A mobile air conditioning system comprising a heat transfer
composition according to claim 1.
20. An air conditioning system in a passenger car or for the
passenger compartment of a truck comprising a heat transfer
composition according to claim 1.
21. A heat transfer composition comprising: (a) HFO-1234ze; (b)
HFC-32; and (c) HFC-134a, the amount of HFC-134a present in the
composition being less than about 6% by weight of the composition
and not less than about 3% of the composition.
22. The heat transfer composition of claim 21 wherein said
composition has a GWP of not greater than 150.
23. The heat transfer composition of claim 21 wherein said
composition has a GWP of not greater than 100.
24. The heat transfer composition of claim 21 wherein said
composition has a hazard value of less than about 7.
25. The heat transfer composition of claim 21 wherein said
composition has a hazard value of less than about 4.
26. The heat transfer composition of claim 21 wherein said
composition has a hazard value of not greater than about 2.
27. The heat transfer composition of claim 21 wherein said
composition has a burning velocity of less than 10.
28. The heat transfer composition of claim 21 wherein said
composition has a capacity relative to HFC-134a under MAC
conditions of from about 90% to about 105%.
29. The heat transfer composition of claim 21 wherein said
composition has a capacity relative to HFC-134a under MAC
conditions of from about 95% to about 101%.
30. The heat transfer composition of claim 21 wherein said
composition has a COP relative to HFC134a under MAC conditions of
from about 98% to about 102%.
31. The heat transfer composition of claim 21 wherein said
composition has a COP relative to HFC134a under MAC conditions of
from about 100%.
32. The heat transfer composition of claim 21 wherein said
composition comprises from about 83% to about 88% by weight of
HFO-1234ze.
33. The heat transfer composition of claim 32 wherein said
HFO-1234ze consists essentially of trans-HFO1234ze.
34. The heat transfer composition of claim 21 wherein said
composition comprises from about 8% to about 12% by weight of
HFC-32.
35. The heat transfer composition of claim 21 wherein HFO-1234ze is
provided in an amount between about 85% and about 86% by weight,
HFC-134a is provided in an amount of about 4.5% by weight and
HFC-32 is provided in an amount between about 9.5% and about 10.5%
by weight.
36. An air conditioning system comprising a heat transfer
composition according to claim 21.
37. A mobile air conditioning system comprising a heat transfer
composition according to claims 21.
38. An air conditioning system in a passenger car or for the
passenger compartment of a truck comprising a heat transfer
composition according to claim 21.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a division of Ser. No.
13/530,585, filed Jun. 22, 2012 which application claims priority
to U.S. Provisional Patent Application No. 61/507,186, filed on
Jul. 13, 2011, the contents of which each are incorporated herein
by reference.
FIELD OF THE INVENTION
[0002] This invention relates to compositions, methods and systems
having utility in numerous applications, including particularly
heat transfer systems such as refrigeration systems. In preferred
aspects, the present invention is directed to refrigerant
compositions particularly well adapted for use in applications in
which the refrigerant 1,1,1,2-tetrafluoroethane (HFC-134a) was
previously and frequently used, including particularly for heating
and/or cooling applications, and for retrofitting refrigerant
and/or air conditioning systems, including systems designed for use
with HFC-134a. The preferred use of such compositions is stationary
refrigeration and air conditioning equipment.
BACKGROUND
[0003] During the course of the past several years, substantial
effort has been devoted to developing more environmentally friendly
alternatives to materials which had previously been frequently used
for refrigeration and air conditioning purposes. During this time,
the main refrigerant used for mobile air conditioning (MAC) systems
had been HFC-134a. Although HFC-134a possesses many properties that
make it attractive for use in MAC systems, it has a relatively high
global warming potential (GWP) of about 1430 (100 years).
[0004] The fluorinated olefin HFO-1234yf has emerged after much
research and development effort by the assignee of the present
invention as the material of choice to replace HFC-134a in MAC
systems. The emergence of HFO-1234yf as the next-generation
material of choice for MAC systems is due primarily to its
exceptional ability to provide a combination of difficult to
achieve properties, such as excellent heat transfer
characteristics, low toxicity, low flammability, and chemical
stability, among other properties. Furthermore, HFO-1234yf is
capable of providing this combination of properties with little or
no need to be blended with other materials.
[0005] Despite the exceptional and extraordinary success of
HFO-1234yf as the next generation refrigerant for many
applications, including particularly MAC systems, the present
applicants have come to appreciate that circumstances may arise in
which HFO-1234yf is not readily available as a result of production
capacity limitations, especially in the near term. Accordingly,
applicants have come to recognize the need for the development of
other materials which might approach the commercial success of
HFO-1234yf as the next generation refrigerant.
[0006] Prior to and subsequent to the development of HFO-1234yf,
much of the effort directed toward next-generation refrigerants was
focused on the development of heat transfer compositions comprised
of a blend or mixture of two or more components. However, these
efforts have thus far been generally less than fully successful
because of a failure to fully realize one or more of the myriad of
properties required for a successful next generation
refrigerant.
[0007] The fluorinated olefin 1,3,3,3-tetrafluoropropene
(HFO-1234ze) has also been identified in an application assigned to
the assignee of the present invention as a next generation
refrigerant due to its advantageous combination of properties. See,
for example, WO 2009/089511. While this application discloses that
HFO-1234ze is very attractive as a refrigerant in many
applications, it also reveals that it has a substantially lower
capacity relative to HFC-134a than does HFO-1234yf in certain air
conditioning applications when each is used as the sole
refrigerant.
[0008] Blends comprising such fluorinated olefins (e.g. 1234ze or
1234yf) have been suggested for use in a wide variety of
applications, including heat transfer compositions. For example, WO
2009/089511, discloses blends comprising as a first component one
or more fluorinated olefins according to a particular structure and
a second component selected from a list of compounds comprising
chloroflurocarbons (CFCs), hydrofluorocarbons (HFCs) water and CO2.
However, the specific combination of components in the particular
concentration ranges required by the present invention are not
disclosed, and no particular combination of these components is
identified in WO 2009/089511 as having the advantageous and
beneficial properties described herein.
[0009] US Application No. 2010/0044619, which is also assigned to
the assignee of the present invention, discloses blends comprising
fluorinated olefins for use in connection with heat transfer
compositions. This application describes blends comprising as a
first component dichloromethane (HFC-32), second component
comprising multi-fluorinated olefins having from 2 to 5 carbon
atoms, and optionally a third component selected from fluorinated
alkanes having to 2 to 3 carbon atoms, CF3I, and combinations of
these. According to this application, the second and/or third
component of the blend is incorporated for the purpose of acting as
of an agent for reducing the flammability of the material relative
to HFC-32 alone. Once again, however, the specific combination of
components in the particular concentration ranges required by the
present invention are not disclosed, and no particular combination
of these components is identified in US Application No.
2010/0044619 as having the advantageous and beneficial properties
described herein.
[0010] Although it is believed that the blends of materials
disclosed in the above-noted applications are generally acceptable
for use in heat transfer applications under certain circumstances,
applicants have found that unexpected yet highly beneficial
advantages can be achieved by careful selection of materials within
a specific concentration range for forming a heat transfer
composition blend which is at once capable of achieving highly
desirable heat transfer properties, extraordinarily beneficial
environmental properties and exceptionally and unexpectedly
nonhazardous compositions from the standpoint of combustion
ignition.
[0011] The burning velocity of a material is one measure that has
heretofore been used to assess the hazardousness of the material
from a flammability or explosive nature stand point. Thus it has
heretofore been considered in many applications that a material
having a burning velocity below a value of 10 (measured as
described hereinafter), is not only important or essential for many
applications, but also that such a material would be considered
generally a non-hazardous material from a flammability or explosive
nature stand point. Applicants have found that certain compositions
exhibit an undesirably high level of hazardousness even when such
compositions contain components that would indicate that the
material is acceptable for use from a burning velocity stand-point,
as discussed more fully hereinafter.
SUMMARY
[0012] Applicants have found that heat transfer compositions having
highly desirable heat transfer and environmental properties can be
produced which also have an unexpectedly advantageous level of
safety or non-hazardousness from the stand point of
flammability/combustion impact. More specifically, applicants have
found that great but unexpected advantages can be achieved by the
use of compositions comprising HFO-1234ze, HFC-32 and a third
component selected from HFC-152a, HFC-134a and combinations of
these.
[0013] For embodiments in which the third component comprises
HFC-152a, it is important in many applications that the amount of
HFC-152a is less than about 20% by weight of the composition, and
even more preferably that the amount of HFC-152a is not greater
than about 15% by weight of the composition, and also preferably
not less than about 5% of the composition. In this regard,
applicants have found that concentrations of HFC-152a of greater
than about 20% in such compositions produce compositions with an
undesirably high level of hazardousness notwithstanding that such
compositions having 20% or greater of HFC-152a would be expected to
have a burning velocity of less than about 10. Thus, applicants
have surprisingly found that tremendous advantage can be achieved
by requiring such compositions to contain less than about 20% by
weight of HFC-152a.
[0014] Applicants have also found that the use of HFC-152a in
amounts of about 5% or less have the undesirable effect of
increasing the evaporation glide of the blend to such a degree that
the use of such blends becomes highly problematic in certain
applications, as explained more fully below.
[0015] For embodiments in which the third component comprises
HFC-134a, it is important in many applications that the amount of
HFC-134a is less than about 6% and greater than about 3% by weight
of the composition, and even more preferably that the amount of
HFC-134a is not greater than about 5% by weight of the composition,
and also preferably not less than about 4% of the composition. In
this regard applicants have found that concentrations of HFC-134a
of greater than about 6% by weight in such compositions produce
compositions with an undesirably high level of global warming
potential, while compositions with amounts of less than about 3% by
weight have capacity and/or COP that diverges greater than a
desired about relative to pure HFC-134a. In such compositions, it
is also preferred that the amount of R-32 in the compositions is
from about 7% to about 15% by weight, more preferably from about 8%
to about 12% by weight, while the HFO-1234ze(E) is present in the
composition in an amount of from about 83% to about 88% by weight,
and even more preferably of from about 84% to about 87% by weight.
Thus, applicants have surprisingly found that tremendous advantage
can be achieved in certain embodiments by requiring such
compositions to have each of the components R-32, HFO-1234ze(E) and
HFO-134a in the amounts described herein. As used herein unless
otherwise indicated, weight percentages for such aspects of the
invention are based upon weight percent of R-32, HFO-1234ze and
HFC-134a in the composition.
[0016] In preferred aspects, the heat transfer compositions,
methods, uses and systems of the present invention comprise or
utilize a multi-component mixture comprising: (a) from about 70% to
about 90% by weight of HFO-1234ze, preferably transHFO-1234ze (also
referred to as HFO-1234ze(E)); (b) from about 5% to about 20% by
weight of HFC-32, (c) from greater than about 5% to less than about
20% by weight of HFC-152a; and (d) optionally HFC-134a in an amount
of from 0% to less than about a 5%. As used herein unless otherwise
indicated, weight percentages are based upon weight percent based
on the total amount of components (a), (b), (c) and (d) present in
the composition.
[0017] In preferred aspects, the heat transfer compositions,
methods, uses and systems of the present invention comprise or
utilize a multi-component composition comprising: (a) HFO-1234ze,
preferably transHFO-1234ze; (b) HFC-32, (c) HFC-152a, and optional
components (d), including particularly HFC-134a, with the relative
amounts of each component (a)-(d) in the composition being
effective to provide said composition with a GWP (as hereinafter
defined) of not greater than 150, and even more preferably not
greater than about 100, and an ignition hazard level (as
hereinafter defined) of not greater than about 7, even more
preferably not greater than about 5, and even more preferably not
greater than about 2. In such embodiments it is also generally
preferred that the composition has a burning velocity (as
hereinafter defined) of not greater than about 10.
[0018] In certain preferred embodiments, the compositions of the
present invention have a relative amount of each component (a)-(d)
effective to provide said composition with a capacity relative to
HFC-134a under MAC conditions (as hereinafter defined) of from
about 90% to about 105%, and even more preferably from about 95% to
about 101%, and a COP relative to HFC-134a under MAC condition (as
hereinafter defined) for from about 98% to about 102%, more
preferably of about 100%.
[0019] In certain preferred embodiments, the compositions of the
present invention have a relative amount of each component (a)-(d)
effective to provide said composition with a Evaporator Glide (as
hereinafter defined) of not greater than about 8, and even more
preferably not greater than about 7.
[0020] In certain highly preferred embodiments, the present
invention comprises or utilizes a multi-component composition
comprising: (a) HFO-1234ze, preferably transHFO-1234ze; (b) HFC-32,
(c) HFC-152a, and optionally (d) HFC-134a, with the relative amount
of each component (a)-(d) in the composition being effective to
provide said composition with: (i) a GWP (as hereinafter defined)
of not greater than 150, and even more preferably not greater than
about 100; (ii) an ignition hazard level (as hereinafter defined)
of not greater than about 7, even more preferably not greater than
about 5, and even more preferably not greater than about 2; (iii) a
capacity relative to HFC-134a under MAC conditions (as hereinafter
defined) of from about 90% to about 105%, and even more preferably
from about 95% to about 101%; (iv) a COP relative to HFC-134a under
MAC condition (as hereinafter defined) for from about 98% to about
102%, more preferably of about 100%; and (v) a Evaporator Glide (as
hereinafter defined) of not greater than about 8, and even more
preferably not greater than about 7.
[0021] The present invention provides also methods and systems
which utilize the compositions of the present invention, including
methods and systems for heat transfer and for retrofitting existing
heat transfer systems. Certain preferred method aspects of the
present invention relate to methods of providing cooling in small
refrigeration systems. Other method aspects of the present
invention provide methods of retrofitting an existing small
refrigeration system designed to contain or containing R-134a
refrigerant comprising introducing a composition of the present
invention into the system without substantial engineering
modification of said existing refrigeration system. According to
certain highly preferred aspects of the present invention, the
refrigeration system and/or refrigeration methods and/or the
refrigerant compositions of the present invention are directed to
mobile air conditioning systems, and even more preferably
automotive air conditioning systems, and even more preferably
air-conditioning systems contained in or used in connection with
passenger cars.
[0022] The term HFO-1234ze is used herein generically to refer to
1,1,1,3-tetrafluoropropene, independent of whether it is the cis-
or trans- form. The terms "cisHFO-1234ze" and "transHFO-1234ze" are
used herein to describe the cis- and trans- forms of 1, 1, 1,
3-tetrafluoropropene respectively. The term "HFO-1234ze" therefore
includes within its scope cisHFO-1234ze, transHFO-1234ze, and all
combinations and mixtures of these.
BRIEF DESCRIPTION OF THE FIGURES
[0023] FIG. 1 illustrates a schematic depiction of the experimental
setup for testing of tubular heaters.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0024] Small refrigeration systems are important in many
applications, as mentioned above. In such systems, one of the
refrigerants that have been commonly used is HFC-134a, which has an
estimated Global Warming Potential (GWP) of 1430. Applicants have
found that the compositions of the present invention satisfy in an
exceptional and unexpected way the need for alternatives and/or
replacements for refrigerants in such applications, particularly
and preferably HFC-134a, that at once have lower GWP values and
provide non-flammable, non-toxic fluids that have a close match in
cooling capacity and/or efficiency (and preferably both) to
HFC-134a in such systems. Applicants have found that the
compositions of the present invention satisfy in an exceptional and
unexpected way the need for new compositions, especially for small
and medium refrigeration applications, having improved performance
with respect to environmental impact while at the same time
providing other important performance characteristics, such as
capacity, efficiency, flammability and toxicity. In preferred
embodiments the present compositions provide alternatives and/or
replacements for refrigerants currently used in these applications,
particularly and preferably HFC-134a, that at once have lower GWP
values and provide a refrigerant composition that has a degree of
hazardousness, as defined hereinafter, that is substantially lower
than the hazardousness of similar compositions but comprising
greater than 20% of HFC-152a, while at the same time maintaining a
desirably low toxicity, and preferably also having a close match in
cooling capacity and/or efficiency to HFC-134a in such systems.
[0025] Heat Transfer Compositions
[0026] The compositions of the present invention are generally
adaptable for use in heat transfer applications, that is, as a
heating and/or cooling medium, but are particularly well adapted
for use, as mentioned above, in low and medium temperature
refrigeration systems, and in automotive AC systems, that have
heretofore used HFC-134a.
[0027] Applicants have found that use of the components of the
present invention within the stated ranges is important to
achieving the highly advantageous combinations of properties
exhibited by the present compositions, particularly in the
preferred systems and methods, and that use of these same
components but substantially outside of the identified ranges can
have a deleterious effect on one or more of the important
properties of the compositions of the invention.
[0028] In certain preferred embodiments, the multi-component
mixture comprises: (a) from about 5% to about 15% by weight of
HFC-32; and (b) from about 70% to about 85% by weight of
HFO-1234ze, preferably transHFO-1234ze; and (c) greater than 5% to
about 18% by weight of HFC-152a.
[0029] In certain preferred embodiments, the multi-component
mixture comprises: (a) from about 5% to about 10% by weight of
HFC-32; and (b) from about 70% to about 80% by weight of
HFO-1234ze, preferably transHFO-1234ze; and (c) greater than 5% to
about 15% by weight of HFC-152a.
[0030] As mentioned above, the preferred compositions exhibit a
degree of hazard value of not greater than about 7. As used herein,
degree of hazardousness is measured by observing the results of a
cube test using the composition in question and applying a value to
that test as indicated by the guidelines provided in the following
table below:
[0031] Hazard Value Guideline Table
TABLE-US-00001 TEST RESULT HAZARD VALUE RANGE (No ignition).
Exemplary of this hazard 0 level are the pure materials R-134a and
transHFO-1234ze. Incomplete burning process and little or no 1-2
energy imparted to indicator balls and no substantial pressure rise
in the cube (all balls rise an amount that is barely observable or
not all from the cube holes and essentially no movement of the cube
observed). Exemplary of this hazard level is the pure material
HFO-1234yf, with a value of 2. Substantially complete burning
process 3-5 and low amount of energy imparted to some of the balls
and substantially no pressure rise in the cube (some balls rise an
observable small distance and return to the starting position, and
essentially no movement of the cube observed). Exemplary of this
hazard level is the pure material R-32, with a value of 4.
Substantially complete burning process 6-7 and substantial amount
of energy imparted to most balls and high pressure rise in the cube
but little or no movement of the cube (most balls rise an
observable distance and do not return to the top of the cube, but
little or no movement of the cube observed). High Hazard Conditions
- Rapid burning 8-10 and substantial imparted to all balls and
substantial energy imparted to the cube (substantially all balls
rise from the cube and do not return to the starting position, and
substantial movement of the cube observed). Exemplary of this
hazard level are the pure materials R-152a and R- 600a, with values
of 8 and 10 respectively.
[0032] The cube test is conducted as indicated in the Examples
below.
[0033] As mentioned above, applicants have found that the
compositions of the present invention are capable of achieving a
difficult combination of properties, including particularly: low
GWP; excellent capacity relative to HFC-134a; excellent efficiency
relative to HFC-134a; an evaporator condition glide of less than
about 8; and a hazard value of not greater than 7, and preferably
of about 5 or less. By way of non-limiting example, the following
Table A illustrates the substantial GWP superiority of certain
compositions of the present invention, which are described in
parenthesis in terms of weight fraction of each component, in
comparison to the GWP of HFC-134a, which has a GWP of 1430.
TABLE-US-00002 TABLE A BV Group # Composition GWP cm/s 32 + 152a +
1234ze A1 R32/R152a/1234ze(E)(0.1/0.15/0.75) 91 4.1 A2
R32/R152a/1234ze(E)(0.08/0.15/0.77) 77 4.0 A3
R32/R152a/1234ze(E)(0.06/0.15/0.79) 64 3.9 32 + (152a + 134a) +
1234ze B1 R32/R152a/1234ze(E)/R134a(0.09/0.15/0.72/0.04) 141 4.6 B2
R32/R152a/1234ze(E)/R134a(0.08/0.15/0.73/0.04) 134 4.5 B3
R32/R152a/1234ze(E)/R134a(0.07/0.15/0.74/0.04) 127 4.5 32 + 134a +
1234ze B4 R32/1234ze(E)/R134a(0.105/0.85/0.045) 140 1.3 B5
R32/1234ze(E)/R134a(0.1/0.855/0.045) 137 1.3 B6
R32/1234ze(E)/R134a(0.095/0.86/0.045) 134 1.3 32 + 152a + 1234ze
(BV <10 C1 R32/R152a/1234ze(E)(0.1/0.2/0.7) 97 5.3 but
hazardous) C2 R32/R152a/1234ze(E)(0.1/0.3/0.6) 109 7.6
[0034] The refrigerant compositions of the present invention may be
incorporated into heat transfer compositions which include not only
the refrigerant having the required and optional components for the
refrigerant, but which also includes other components for the
purpose of enhancing or providing certain functionality to the
composition, or in some cases to reduce the cost of the
composition. For example, heat transfer compositions according to
the present invention, especially those used in vapor compression
systems, include in addition to components (a)-(d) as mentioned
above, but also a lubricant, generally in amounts of from about 30
to about 50 percent by weight of the composition, based on the
total of the refrigerant composition and the lubricant, and in some
cases potentially in amount greater than about 50 percent and other
cases in amounts as low as about 5 percent by weight.
[0035] Commonly used refrigeration lubricants such as Polyol Esters
(POEs) and Poly Alkylene Glycols (PAGs), PAG oils, silicone oil,
mineral oil, alkyl benzenes (ABs) and poly(alpha-olefin) (PAO) that
are used in refrigeration machinery with hydrofluorocarbon (HFC)
refrigerants may be used with the refrigerant compositions of the
present invention. Commercially available mineral oils include
Witco LP 250 (registered trademark) from Witco, Zerol 300
(registered trademark) from Shrieve Chemical, Sunisco 3GS from
Witco, and Calumet R015 from Calumet. Commercially available alkyl
benzene lubricants include Zerol 150 (registered trademark).
Commercially available esters include neopentyl glycol
dipelargonate, which is available as Emery 2917 (registered
trademark) and Hatcol 2370 (registered trademark). Other useful
esters include phosphate esters, dibasic acid esters, and
fluoroesters. In some cases, hydrocarbon based oils are have
sufficient solubility with the refrigerant that is comprised of an
iodocarbon, the combination of the iodocarbon and the hydrocarbon
oil might more stable than other types of lubricant. Such
combination may therefore be advantageous. Preferred lubricants
include polyalkylene glycols and esters. Polyalkylene glycols are
highly preferred in certain embodiments because they are currently
in use in particular applications such as mobile air-conditioning.
Of course, different mixtures of different types of lubricants may
be used.
[0036] Heat Transfer Methods and Systems
[0037] The present methods, systems and compositions are thus
adaptable for use in connection with a wide variety of heat
transfer systems in general and refrigeration systems in
particular, such as air-conditioning (including both stationary and
mobile air conditioning systems), refrigeration, heat-pump systems,
and the like. In certain preferred embodiments, the compositions of
the present invention are used in refrigeration systems originally
designed for use with an HFC refrigerant, such as, for example,
R-134a. The preferred compositions of the present invention tend to
exhibit many of the desirable characteristics of R-134a but have a
GWP that is substantially lower than that of R-134a while at the
same time having a capacity and/or efficiency (as measured by COP)
that is substantially similar to or substantially matches, and
preferably is as high as or higher than R-134a. In particular,
applicants have recognized that certain preferred embodiments of
the present compositions tend to exhibit relatively low global
warming potentials ("GWPs"), preferably less than about 150, and
more preferably not greater than about 100, while at the same time
achieving a hazard value of less than about 7, and even more
preferably of not greater than about 5.
[0038] As mentioned above, the present invention achieves
exceptional advantages in connection with systems known as low
temperature refrigeration systems. As used herein the term "low
temperature refrigeration systems" refers to vapor compression
refrigeration systems which utilize one or more compressors and a
condenser temperature of from about 35.degree. C. to about
75.degree. C. In preferred embodiments, the systems have an
evaporator temperature of from about 10.degree. C. to about
-35.degree. C., with an evaporator temperature preferably of about
-10.degree. C. Moreover, in preferred embodiments, the systems have
a degree of superheat at evaporator outlet of from about 0.degree.
C. to about 10.degree. C., with a degree of superheat at evaporator
outlet preferably of from about 4.degree. C. to about 6.degree. C.
Furthermore, in preferred embodiments of such systems, the systems
have a degree of superheat in the suction line of from about
1.degree. C. to about 15.degree. C., with a degree of superheat in
the suction line preferably of from about 5.degree. C. to about
10.degree. C.
[0039] Another preferred system of the present invention is
referred to herein as a "automotive AC or MAC systems." Such
systems have an evaporator temperature of from about 0.degree. C.
to about 20.degree. C. and a CT of from about 30.degree. C. to
about 95.degree. C. Moreover, in preferred embodiments of such
systems, the systems have a degree of superheat at evaporator
outlet of from about 2.degree. C. to about 10.degree. C., with a
degree of superheat at evaporator outlet preferably of from about
4.degree. C. to about 7.degree. C. Furthermore, in preferred
embodiments of such systems, the systems have an increase of
temperature in the suction line of from about 0.5.degree. C. to
about 5.degree. C., with an increase of temperature in the suction
line preferably of from about 1.degree. C. to about 3.degree.
C.
[0040] As mentioned above, the present invention also achieves
exceptional advantage in connection with systems known as medium
temperature refrigeration systems. As used herein the term "medium
temperature refrigeration system" refers to vapor compression
refrigeration systems which utilize one or more compressors and a
condenser temperature of from about 35.degree. C. to about
75.degree. C. In preferred embodiments of such systems, the systems
have an evaporator temperature of from about 10.degree. C. to about
-35.degree. C., with an evaporator temperature preferably of about
-10.degree. C. Moreover, in preferred embodiments of such systems,
the systems have a degree of superheat at evaporator outlet of from
about 0.degree. C. to about 10.degree. C., with a degree of
superheat at evaporator outlet preferably of from about 4.degree.
C. to about 6.degree. C. Furthermore, in preferred embodiments of
such systems, the systems have a degree of superheat in the suction
line of from about 1 .degree. C. to about 15.degree. C., with a
degree of superheat in the suction line preferably of from about
5.degree. C. to about 10.degree. C.
EXAMPLES
[0041] The following examples are provided for the purpose of
illustrating the present invention but without limiting the scope
thereof.
Compositions Tested
[0042] The following compositions within the scope of the present
invention are the utilized in the examples which follow:
TABLE-US-00003 COMPOSITION wt % transHFO- Wt % Wt % DESIGNATION
1234ze HFC-32 HFC-152 Wt % 134a A1 75 10 15 0 A2 77 8 15 0 A3 79 6
15 0 B1 72 9 15 4 B2 73 8 15 4 B3 74 7 15 4 B4 85 10.5 0 4.5 B5
85.5 10 0 4.5 B6 86 9.5 0 4.5 C1 70 10 20 0 C2 60 10 30 0
Example 1: Auto AC Conditions
[0043] This example illustrates the performance of embodiments
A1-A3 and B1-B3 of the present invention when used as a replacement
for HFC-134a in a auto AC refrigerant systems. The system is one
have an evaporator temperature (ET) of about 4.degree. C., with a
degree of superheat at the evaporator outlet of about 5.degree. C.,
and condenser temperature (CT) of about 60.degree. C., with about
5.degree. C. subcooling. The system has a degree of superheat at
the suction line of about 10.degree. C. and an efficiency of about
70%.
[0044] The coefficient of performance (COP) is a universally
accepted measure of refrigerant performance, especially useful in
representing the relative thermodynamic efficiency of a refrigerant
in a specific heating or cooling cycle involving evaporation or
condensation of the refrigerant. In refrigeration engineering, this
term expresses the ratio of useful refrigeration to the energy
applied by the compressor in compressing the vapor. The capacity of
a refrigerant represents the amount of cooling or heating it
provides and provides some measure of the capability of a
compressor to pump quantities of heat for a given volumetric flow
rate of refrigerant. In other words, given a specific compressor, a
refrigerant with a higher capacity will deliver more cooling or
heating power. One means for estimating COP of a refrigerant at
specific operating conditions is from the thermodynamic properties
of the refrigerant using standard refrigeration cycle analysis
techniques (see for example, R. C. Downing, FLUOROCARBON
REFRIGERANTS HANDBOOK, Chapter 3, Prentice-Hall, 1988).
[0045] The properties of each composition and its performance in
the exemplary auto AC system is observed to be as follows these
operating parameters are reported in the table below, with the
performance based upon HFC-134a having a COP value of 1.00 and a
capacity value of 1.00:
TABLE-US-00004 Eff Ev Cap % of Full % of 134 Glide BV Hazard
Composition GWP 134 (COP) C cm/s Value A1
R32/R152a/1234ze(E)(0.1/0.15/0.75) 91 100% 101% 7.38 4.1 4 A2
R32/R152a/1234ze(E)(0.08/0.15/0.77) 77 97% 101% 6.55 4.0 4 A3
R32/R152a/1234ze(E)(0.06/0.15/0.79) 64 93% 101% 5.50 3.9 4 B1
R32/R152a/1234ze(E)/R134a(0.09/0.15/0.72/0.04) 141 100% 101% 675
4.6 4 B2 R32/R152a/1234ze(E)/R134a(0.08/0.15/0.73/0.04) 134 98%
101% 6.32 4.5 4 B3 R32/R152a/1234ze(E)/R134a(0.07/0.15/0.74/0.04)
127 96% 101% 5.85 4.5 4
[0046] The EV full glide is determined by taking the deference
between the bubble point and dew under evaporating conditions of
the system.
[0047] The Hazard Value is determined as described above using the
Cube Test. The Cube Test is performed pursuant to the procedure
described herein. Specifically, each material being tested is
separately released into a transparent cube chamber which has an
internal volume of 1 ft3. A low power fan is used to mix
components. An electrical spark with enough energy to ignite the
test fluids is used. The results of all tests are recorded using a
video camera. The cube is filled with the composition being tested
so as to ensure a stoichiometric concentration for each refrigerant
tested. The fan is used to mix the components. Effort is made to
ignite the fluid using the spark generator for 1 min. Record the
test using HD camcorder.
[0048] A schematic of the experimental setup for testing of tubular
heaters is illustrated in FIG. 1.
Example 2: Auto AC Conditions
[0049] This example illustrates compositions within the scope of
certain aspects of the present invention, namely compositions B4-B6
which do not contain HFC-152a, but which do contain HFC-134a using
an auto AC system operated is in Example 1. The results are
reported in the following table:
TABLE-US-00005 Cap Eff % % of of 134 Ev Full BV Hazard Composition
GWP 134 (COP) Glide C cm/s Value B4
R32/1234ze(E)/R134a(0.105/0.85/0.045) 140 99% 99% 9.19 1.3 0.5 B5
R32/1234ze(E)/R134a(0.1/0.855/0.045) 137 97% 99% 9.00 1.3 0.5 B6
R32/1234ze(E)/R134a(0.095/0.86/0.045) 134 96% 99% 8.80 1.3 0.5
[0050] As can be seen from the results reported above, the
compositions which do not contain HFC-152a but which contain
HFC-134a in accordance with the teachings contained herein show an
excellent but unexpected combination of properties, including low
GWP, low burning velocity and hazard value and excellent capacity
and COP. The glide of such compositions may be higher than desired
for some applications, but is acceptable for many applications.
Comparative Example C1: Auto AC Conditions
[0051] This example illustrates the performance of the compositions
outside the scope of the present invention, namely compositions C1
and C2, using an auto AC system operated is in Example 1. The
results are reported in the following table:
TABLE-US-00006 Cap Eff % % of of 134 Ev Full BV Hazard Composition
GWP 134 (COP) Glide C cm/s Value C1
R32/R152a/1234ze(E)(0.1/0.2/0.7) 97 102% 102% 7.17 5.3 7 C2
R32/R152a/1234ze(E)(0.1/0.3/0.6) 109 102% 102% 6.16 7.6 7
[0052] As can be seen from the results reported above, the
compositions which contain 20 percent by weight or greater of
HFC-152a each exhibit a detrimentally and unexpectedly high hazard
value, notwithstanding that each composition also has a calculated
burning velocity of less than 10.
Example 3: Medium Temperature Conditions
[0053] This example illustrates the performance of embodiments
A1-A3 and B1-B3 of the present invention when used as a replacement
for HFC-134a in a Medium temperature refrigerant system. The system
is one have an evaporator temperature (ET) of about -10.degree. C.,
with a degree of superheat at the evaporator outlet of about
5.degree. C., and condenser temperature (CT) of about 5.degree. C.,
with about 5.degree. C. subcooling. The system has a degree of
superheat at the suction line of about 45.degree. C. and an
efficiency of about 70%.
[0054] The properties of the composition and its performance in the
exemplary medium temperature system is observed to be as
follows:
TABLE-US-00007 Eff Ev Cap % of Full % of 134 Glide BV Hazard
Composition GWP 134 (COP) C cm/s Value A1
R32/R152a/1234ze(E)(0.1/0.15/0.75) 91 101% 100% 7.72 4.1 4 A2
R32/R152a/1234ze(E)(0.08/0.15/0.77) 77 97% 100% 6.88 4.0 4 A3
R32/R152a/1234ze(E)(0.06/0.15/0.79) 64 93% 100% 5.81 3.9 4 B1
R32/R152a/1234ze(E)/R134a(0.09/0.15/0.72/0.04) 141 100% 100% 7.07
4.6 4 B2 R32/R152a/1234ze(E)/R134a(0.08/0.15/0.73/0.04) 134 98%
100% 6.64 4.5 4 B3 R32/R152a/1234ze(E)/R134a(0.07/0.15/0.74/0.04)
127 96% 100% 6.15 4.5 4
[0055] The EV full glide and Hazard Value are each determined as
indicated in Example 1 above.
Example 4: Medium Temperature Conditions
[0056] This example illustrates compositions within the scope of
certain aspects of the present invention, namely compositions B4-B6
which do not contain HFC-152a, but which do contain HFC-134a, using
an auto medium temperature system operated is in Example 2. The
results are reported in the following table:
TABLE-US-00008 Cap Eff % % of of 134 Ev Full BV Hazard Composition
GWP 134 (COP) Glide C cm/s Value B4
R32/1234ze(E)/R134a(0.105/0.85/0.045) 140 100% 99% 9.63 1.3 0.5 B5
R32/1234ze(E)/R134a(0.1/0.855/0.045) 137 99% 99% 9.44 1.3 0.5 B6
R32/1234ze(E)/R134a(0.095/0.86/0.045) 134 97% 99% 9.23 1.3 0.5
[0057] As can be seen from the results reported above, the
compositions which do not contain HFC-152a but which contain
HFC-134a in accordance with the teachings contained herein show an
excellent but unexpected combination of properties, including low
GWP, low burning velocity and hazard value and excellent capacity
and COP. The glide of such compositions may be higher than desired
for some applications, but is acceptable for many applications.
Comparative Example 2C: Medium Temperature Conditions
[0058] This example illustrates the performance of the compositions
outside the scope of the present invention, namely compositions C1
and C2, using a medium temperature system operated is in Example 2.
The results are reported in the following table:
TABLE-US-00009 Cap Eff % % of of 134 Ev Full BV Hazard Composition
GWP 134 (COP) Glide C cm/s Value C1
R32/R152a/1234ze(E)(0.1/0.2/0.7) 96 105% 101% 7.32 5.3 7 C2
R32/R152a/1234ze(E)(0.1/0.3/0.6) 108 104% 101% 6.26 7.6 7
[0059] As can be seen from the results reported above, the
compositions which contain 20 percent by weight or greater of
HFC-152a each exhibit a detrimentally and unexpectedly high hazard
value, notwithstanding that each composition also has a calculated
burning velocity of less than 10.
* * * * *