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Abstract:

A fire suppression non-aqueous liquid concentrate includes starch, a
pseudo-plastic, high yield, suspending agent, a C10-18 paraffin or a
C10-18 olefin, a non-ionic surfactant, and an alcohol amine
neutralizer. The non-aqueous liquid concentrate forms a dilute dispersion
when added to water. The dilute dispersion clings to a surface, and forms
an intumescent char coating upon fire contact.

Claims:

1. A fire suppression non-aqueous liquid concentrate comprising; starch;
a pseudo-plastic, high yield, suspending agent; a C10-18 paraffin or
a C10-18 olefin; a non-ionic surfactant; an alcohol amine
neutralizer; and wherein the non-aqueous liquid concentrate forms a fire
suppressing dispersion when added to water; whereby the fire suppressing
dispersion clings to a surface, and forms an intumescent char coating
upon fire contact.

2. The liquid concentrate according to claim 1 wherein the paraffin
comprises a C14 to C16 linear alkane or the olefin comprises a
C14 to C16 linear alpha olefin.

3. The liquid concentrate according to claims 1 to 2 wherein the
pseudo-plastic, high yield, suspending agent comprises an acrylic acid
copolymer cross linked with a polyalkenyl polyether.

10. A method of forming a fire suppression non-aqueous liquid concentrate
comprising: combining a C10-18 paraffin or a C10-18 olefin with
a non-ionic surfactant and an alcohol amine neutralizer to form a first
liquid composition; combining a pseudo-plastic, high yield, suspending
agent to the first liquid composition to form a second liquid
composition; combining a smectite clay to the second liquid composition
to form a third liquid composition; and combining starch to the third
liquid composition to form a fire suppression non-aqueous liquid
concentrate.

11. The method according to claim 10 wherein the liquid concentrate
comprises less than 5 wt % water.

12. The method according to claims 10 and 11 wherein first liquid
composition is mixed until a homogenous first liquid composition is
formed and the second liquid composition is mixed until a homogenous
second liquid composition is formed and the third liquid composition is
mixed until a homogenous third liquid composition is formed and the fire
suppression non-aqueous liquid concentrate is mixed until a homogenous
fire suppression non-aqueous liquid concentrate is formed.

15. A method comprising: diluting the non-aqueous liquid concentrate of
claims 1 to 9 with water to form a fire suppression dispersion comprising
from 0.05 to 10 wt % non-aqueous liquid concentrate, wherein the fire
suppression dispersion clings to a surface and forms an intumescent char
coating upon fire contact.

16. The method according to claim 15 further comprising directing the
fire suppression dispersion onto a surface to suppress fire.

17. The method according to claim 15 wherein the diluting occurs on a
fire firefighting vehicle.

18. The method according to claim 15 wherein the diluting occurs within
fire firefighting equipment.

Description:

BACKGROUND

[0001] Fire is a continuing danger to life and property worldwide. In
rural areas forest, brush, and grassland fires cause immense damage each
year. This destruction is not only in terms of the dollar value of
timber, wildlife and livestock, but the catastrophic effects on erosion,
watershed equilibrium and related problems to the natural environment. In
urban areas fire, and the damage from large quantities of water used to
extinguish a fire, are responsible for the destruction of buildings, with
the loss of billions of dollars annually. Most importantly, fire is a
major danger to human life.

[0002] Over the years man has found numerous methods for combating fires.
The use of water, chemicals and other extinguishing materials are well
documented. Water treated with a wetting agent has been proven to be more
effective on a Class A fire where good water penetration is needed to
reach and extinguish the seat of the fire. Currently, there have been
efforts in the area of pretreatment with chemical retardants or
suppressants. A number of these pretreatments have been developed and
used for fighting rural forest fires. For example, antimony oxide and its
complexes, borates, carbonates, bicarbonates, ammonium phosphate,
ammonium sulfates, and other salts capable of being hydrated, have been
demonstrated to have useful properties as firefighting chemicals.
However, although the fire inhibiting properties of the borates,
carbonates and bicarbonates have been established, the use of these
materials for vegetation fires has been limited because of their tendency
to inhibit plant growth when used in large quantities.

[0003] Another method of fighting fires is the pretreatment of
flame-retardant materials on combustible surfaces that lead to the
creation of intumescent coating materials. Intumescent materials expand
with heat, similar to a vermiculite which expands when exposed to steam.
The expanded layer then protects the original surface from heat and
flame. The problem is that an expanded intumescent is also very fragile.
This problem was soon realized, and the intumescent needed a protective
hard outer coating. This lead to methods using carbonaceous materials to
form a char instead of the materials being consumed by the fire.

[0004] In addition to all these problems, the most difficult problem to
overcome for chemical retardant formulations is that they are relatively
expensive, compared to water. Also of concern is the environmental impact
of absorbent particles presently used in various gel formulations. The
absorbent particles pose an environmental risk once used to fight a fire,
particularly when used on a large scale, such as a forest fire. The cost
factor also comes into conflict with applying them in large quantities,
as is often required. In combating or preventing forest, brush and grass
range fires, a considerable amount of effort has been spent in the search
for low cost or waste materials that are both available in quantity and
inexpensive.

BRIEF SUMMARY

[0005] The present disclosure relates to a non-aqueous fire suppressing
liquid concentrate. In particular the present disclosure relates to a
non-aqueous fire suppressing liquid concentrate that when added to water
forms a dilute dispersion. The dilute dispersion can cling to a surface
and suppress or extinguish a fire.

[0006] In one illustrative embodiment, a fire suppression non-aqueous
liquid concentrate includes starch, a pseudo-plastic, high yield,
suspending agent, a C10-18 paraffin or a C10-18 olefin, a
non-ionic surfactant, and an alcohol amine neutralizer. The non-aqueous
liquid concentrate forms a dilute dispersion when added to water. The
dilute dispersion has a pH in the range of 5.0 to 8.0, and the dilute
dispersion clings to a surface, and forms an intumescent char coating
upon fire contact.

[0007] In another illustrative embodiment, a method of forming a fire
suppression non-aqueous liquid concentrate includes combining a
C10-18 paraffin or a C10-18 olefin with a non-ionic surfactant
and an alcohol amine neutralizer to form a first liquid composition. Then
the method includes combining a pseudo-plastic, high yield, suspending
agent to the first liquid composition to form a second liquid
composition. Then combining a smectite clay to the second liquid
composition to form a third liquid composition, and combining starch to
the third liquid composition to form a fire suppression non-aqueous
liquid concentrate.

[0008] In a further illustrative embodiment, a method includes diluting
the non-aqueous liquid concentrate with water to form a fire suppression
dispersion having from 0.1 to 10 wt % non-aqueous liquid concentrate. The
fire suppression dispersion clings to a surface and forms an intumescent
char coating upon fire contact.

[0009] These and various other features and advantages will be apparent
from a reading of the following detailed description.

DETAILED DESCRIPTION

[0010] In the following description, it is to be understood that other
embodiments are contemplated and may be made without departing from the
scope or spirit of the present disclosure. The following detailed
description, therefore, is not to be taken in a limiting sense. U.S.
Provisional Application No. 61/320,870 filed Apr. 5, 2010 is herein
incorporated by reference in its entirety.

[0011] Unless otherwise indicated, all numbers expressing feature sizes,
amounts, and physical properties used in the specification and claims are
to be understood as being modified in all instances by the term "about."
Accordingly, unless indicated to the contrary, the numerical parameters
set forth in the foregoing specification and attached claims are
approximations that can vary depending upon the desired properties sought
to be obtained by those skilled in the art utilizing the teachings
disclosed herein.

[0012] As used in this specification and the appended claims, the singular
forms "a", "an", and "the" encompass embodiments having plural referents,
unless the content clearly dictates otherwise. As used in this
specification and the appended claims, the term "or" is generally
employed in its sense including "and/or" unless the content clearly
dictates otherwise.

[0013] The present disclosure relates to non-aqueous fire suppressing
liquid concentrates. In particular the present disclosure relates to
non-aqueous fire suppressing liquid concentrates that when added to water
forms a dilute dispersion. The dilute dispersion can cling to a surface
and form an intumescent char coating upon fire contact. The non-aqueous
fire suppressing liquid concentrate includes starch, a pseudo-plastic,
high yield, suspending agent, a C10-18 paraffin or a C10-18
olefin, a non-ionic surfactant, and an alcohol amine neutralizer. The
present disclosure also relates to a method of making the non-aqueous
fire suppressing liquid concentrates. The components are combined as
described herein to obtain a stable non-aqueous fire suppressing liquid
concentrate. The present disclosure also relates to a method of using the
non-aqueous fire suppressing liquid concentrates. The non-aqueous fire
suppressing liquid concentrates can be diluted with water and directed
toward a surface to suppress or extinguish a fire. The non-aqueous fire
suppressing liquid concentrates can be diluted (e.g., dispersed in water)
on or in a fire fighting vehicle or within fire fighting equipment. While
the present disclosure is not so limited, an appreciation of various
aspects of the disclosure will be gained through a discussion of the
examples provided below.

[0014] The disclosed non-aqueous fire suppressing liquid concentrates can
be augmentations to water and used to extinguish fires, for example. The
non-aqueous fire suppressing liquid concentrates can be diluted with
water by any suitable method to form the fire suppressing dispersion. In
many embodiments, the non-aqueous fire suppressing liquid concentrate can
be directed into water by any suitable method. For example the
non-aqueous fire suppressing liquid concentrates can be added to a water
reservoir or injected or educted directly into a liquid stream that may
be directed to a substrate for fire suppression or fire retarding.

[0015] The non-aqueous liquid concentrates use starch, a pseudo-plastic,
high yield, suspending agent, a C10-18 paraffin or a C10-18
olefin, a non-ionic surfactant, and an alcohol amine neutralizer, added
to water to produce a stable, augmentation to water (i.e., fire
suppressing dispersion). In many embodiments, when diluted or dispersed
into water or injected into a stream of water, the fire suppressing
liquid concentrate can make up from 0.05 to 10 wt % or from 0.1 to 5 wt %
of the fire suppressing dispersion.

[0016] The fire suppressing dispersion is easily pumped or sprayed by
typical high pressure pumping equipment or by low-pressure individual
back tanks. The fire suppressing dispersion has a "high yield value,"
meaning it has an initial resistance to flow under stress but then is
shear thinning, and when used, exhibits "vertical cling," meaning it has
the ability at rest, to return to a pseudo-plastic or thixotropic gel.
The fire suppressing dispersion does not readily separate or settle and
can be easily sprayed and thickens when it contacts a wall or ceiling
surface. This gives the firefighter, for example, the ability, unlike
water alone, to build thickness and hold the fire suppressing dispersion
on vertical or overhead surfaces. While not wishing to be bound to any
particular theory, it is believed that the fire suppressing dispersion's
mass and the vertical cling both act as a heat sink capable of clinging
to vertical and overhead surfaces. This clinging to the surfaces causes
the overall temperature of the surfaces to generally remain at or below
the boiling point of water. The heat sink effect does not allow the
temperature of the surface coated with the fire suppressing dispersion of
the composition to exceed 100 degree centigrade until the water in the
composition has been evaporated.

[0017] In many embodiments the non-aqueous fire suppressing liquid
concentrate includes starch, a pseudo-plastic, high yield, suspending
agent, a C10-18 paraffin or a C10-18 olefin, a non-ionic
surfactant, and an alcohol amine neutralizer and optionally a smectite
clay. These materials can be mixed or blended utilizing a mixer to obtain
a homogenous and stable non-aqueous fire suppressing liquid concentrate
composition. It has been found that these non-aqueous fire suppressing
liquid concentrate compositions quickly form a stable gels, suspensions
or dispersions when combined with water. In many embodiments, the diluted
fire suppressing gel, dispersion or suspension has a pH in the range of
5.0 to 8.0 and the fire suppressing gel, dispersion or suspension clings
to a surface positioned at nearly any orientation, and forms an exterior
intumescent char coating upon fire contact, while retaining an interior
aqueous gel composition.

[0018] In many embodiments the non-aqueous fire suppressing liquid
concentrate includes 30-40 wt % pseudoplastic, high yield, suspending
agent, 0.1-20 wt % starch, 30-50 wt % C10-18 paraffin or a
C10-18 olefin, 0.5-5 wt % non-ionic surfactant, 5-10 wt % alcohol
amine, and 0.1 to 5 wt % smectite clay. The non-aqueous fire suppressing
liquid concentrate is substantially free of water. In many embodiments
the non-aqueous fire suppressing liquid concentrate includes less than 5
wt % water, or less than 3 wt % water, or less than 2 wt % water, or less
than 1 wt % water. Maintaining a low water content has been found to be
improve the stability and usefulness of the non-aqueous fire suppressing
liquid concentrate.

[0019] There are many types of pseudo-plastic high yield suspending agents
or rheology modifiers that can be used successfully in the inventive
composition. One major group of such suspending agents are known by their
trade designation CARBOPOL® (generally high molecular weigh homo- and
copolymers of acrylic acid cross linked with a polyalkenyl polyether).
CARBOPOL® are particularly effective pseudo-plastic high yield
suspending agents. One particularly useful material is CARBOPOL® EZ-3,
a hydrophobically modified cross-linked polyacrylate powder. The polymer
is self-wetting and can require low agitation for dispersion. The
convenience of low agitation is very evident in the very short wetting
out time needed, when making a concentrate. CARBOPOL® EZ-3 is
commercially available from Noveon, Inc., Cleveland, Ohio 44141. These
materials have a shear thinning rheology so they can be pumped or sprayed
onto a surface without the loss of cling. Other suitable pseudo-plastic,
high yield, suspending agents may include modified guar and xantham gums,
casein, alginates, modified cellulose, including methyl cellulose,
hydroxyethyl cellulose, hydroxypropyl cellulose and carbomethyl
cellulose, gum tragacanth, synthetic polymers such as polyvinyl alcohol,
polyvinyl acetate, polyethylene oxide, polypropylene oxide and
polyvinylpyrolidone, to name a few used individually or in combination.

[0020] The non-aqueous fire suppressing liquid concentrate and resulting
fire suppressing dispersion can have a high yield value with a "shear
thinning capacity" which means, the non-aqueous fire suppressing liquid
concentrate or fire suppressing dispersion becomes thin when pumped and
thixotropic or pseudoplastic or sag resistant, at rest. Thus, after being
pumped and sprayed, the non-aqueous fire suppressing liquid concentrate
or fire suppressing dispersion is capable of clinging to a vertical,
inclined, or overhead surface.

[0021] Any starch can be used in the non-aqueous fire suppressing liquid
concentrate. Examples of starches and their modifications, include corn,
wheat, potato, tapioca, barley, arrowroot, rice or any combination of
starches. It is believed that dry starch contains about 12% water and has
a particle size in a range from 1 to 50 micrometers. When soaked in
water, the starch associates and holds up to 18% water and the particle
size increases to 40 micrometers. As the fire suppressing dispersion is
heated (e.g., by a fire), the starch forms a gel or association with the
surrounding water starting around 70 degrees centigrade. Thus, when the
fire suppressing dispersion is heated, either from the substrate or the
air side, the starch absorbs more water at the interface and becomes
thicker. Then it is believed that on the substrate side, the fire
suppressing dispersion first rides on its own vapor and, as it cools,
forms its own film on the substrate surface. On the air side, where
evaporation largely occurs, the fire suppressing dispersion first
thickens and then crusts over and eventually is converted to a carbonized
char. The char formed is a hard, intumescent coating, which slows the
evaporation of water from the fire suppressing dispersion. In essence,
the fire suppressing dispersion's own film and char act as a vessel to
contain the soft-gelled composition, which now acts as a heat sink to
cool the backside of the intumescent char. This synergism between the
intumescent hard coating and the fire suppressing dispersion's aqueous
gel helps optimize the amount of water. The char/gel coating further
reduces the available combustible material to the fire, and also reduces
the smoke emission.

[0022] Hydrophobic agglomerating material can be added to the non-aqueous
fire suppressing liquid concentrate. It has been found that the
hydrophobic agglomerating material improves the material properties as
compared to compositions that do not include the composition. While not
wishing to be bound to any particular theory, it is believed that the
hydrophobic agglomerating material improves the speed at which the
aqueous gel or aqueous suspension is formed. In many fire suppression
applications, quick formation of the aqueous gel or aqueous suspension is
important.

[0023] In some embodiments the hydrophobic agglomerating material includes
liquid paraffins or olefins. Paraffin is the common name for alkane
hydrocarbons with the general formula CnH2n+2. Liquid paraffin
generally have less than 20 carbon atoms. In many embodiments the
paraffin has from 10 to 18 carbon atoms or 10 to 14 carbon atoms and is
linear, or has from 14 to 16 carbon atoms and is a linear alkane. Olefin
is the common name for alkene hydrocarbons with the general formula
CnH2n where the hydrocarbon is not saturated. In many
embodiments the olefin has from 10 to 18 carbon atoms or 10 to 14 carbon
atoms and is linear, or has from 14 to 16 carbon atoms and is a linear
alpha olefin.

[0024] Commercially available paraffins and olefins include BIO-BASE®
100LF (linear internal olefin with a carbon chain length between C15 and
C18), BIO-BASE® 300 (linear paraffin with a carbon chain length
between C11 and C14), BIO-BASE® 200 (linear alpha olefin with a carbon
chain length between C16 and C18), BIO-BASE® 220 (linear alpha olefin
with a carbon chain length between C14 and C16), BIO-BASE® 250 (linear
alpha olefin with a carbon chain length between C14 and C18),
BIO-BASE® 360 (blend of iso-paraffins and linear paraffins with a
carbon chain length between C15 and C16), all are available from Shrieve
Chemical Products Company (Woodlands, Tex.). It has been found that the
presence of the hydrophobic agglomerating material improves the
performance of the non-aqueous fire suppressing liquid concentrate.

[0025] The non-aqueous fire suppressing liquid concentrate can include a
neutralizer (e.g., a basic neutralizing material.) In many embodiments
the basic neutralizing material is any material capable of increasing pH
when added to an aqueous material (e.g., forming the aqueous suspension).
In many embodiments the basic material includes other neutralizers. In
some embodiments the basic neutralizing material includes an alcohol
amine neutralizer such as, for example, an amino-methyl-propanol (e.g.,
2-amino-2-methly-1-propanol). One commercially available alcohol amine is
AMP-100® and is available from Angus Chemical Company, for example.

[0026] The non-aqueous fire suppressing liquid concentrate can include a
surfactant. In many embodiments the surfactant is a non-ionic surfactant.
In some embodiments the non-ionic surfactant includes an alkoxylated
alcohol non-ionic surfactant. One commercially available alkoxylated
alcohol non-ionic surfactant is DeIonic® LF-EP-61 and is available
from DeForest Enterprises Inc., (Boca Raton, Fla.) for example.

[0027] The non-aqueous fire suppressing liquid concentrate can include a
smectite clay. The smectite clay can be included in any useful amount and
can act as a suspending agent. Commercially available smectite clay is
available under the trade designations Bentone® SDI and Bentone®
SD3 and is available from Elementis Specialities Inc., (Highstown, N.J.)
for example.

[0028] It has been found that the stability of the non-aqueous fire
suppressing liquid concentrate can depend upon the order of addition of
the components of the non-aqueous fire suppressing liquid concentrate. A
stable non-aqueous fire suppressing liquid concentrate has been formed
when combined in the following manner. First, combining a C10-18
paraffin or a C10-18 olefin with a non-ionic surfactant and an
alcohol amine neutralizer to form a first liquid composition; then
combining a pseudo-plastic, high yield, suspending agent to the first
liquid composition to form a second liquid composition; then combining a
smectite clay to the second liquid composition to form a third liquid
composition; and finally combining starch to the third liquid composition
to form a fire suppression non-aqueous liquid concentrate. It is believed
that the clay and starch are added last since they contain the most water
and minimizing the amount of water in the non-aqueous fire suppressing
liquid concentrate has been found to unexpectedly enhance stability of
the non-aqueous fire suppressing liquid concentrate.

[0029] One exemplary non-aqueous fire suppressing liquid concentrate is
formed by combining a C10-18 paraffin or a C10-18 olefin (e.g.,
BIO-BASE® 200) with a non-ionic surfactant (e.g., DeIonic®
LF-EP-61) and an alcohol amine neutralizer (AMP-100) to form a first
liquid composition. This first liquid composition was mixed to form a
homogenous first liquid composition. Then combining a pseudo-plastic,
high yield, suspending agent (e.g., CARBOPOL® EZ-3) to the first
liquid composition to form a second liquid composition. This second
liquid composition was mixed to form a homogenous second liquid
composition. Then combining a smectite clay (e.g., Bentone SD-3) to the
second liquid composition to form a third liquid composition. This third
liquid composition was mixed to form a homogenous third liquid
composition. Finally combining starch (e.g., corn starch) to the third
liquid composition to form a fire suppression non-aqueous liquid
concentrate and mixed until the liquid material is homogenous. One
exemplary fire suppressing liquid concentrate was formed by combining 40
wt % BIO-BASE® 200, 1 wt % DeIonic® LF-EP-61, 7 wt % AMP-100, 36 wt
% CARBOPOL® EZ-3, 1.5 wt % Bentone SD-3, and 14.5 wt % corn starch. Wt
% is based on the total weight of the non-aqueous fire suppressing liquid
concentrate.

[0030] The resulting non-aqueous fire suppressing liquid concentrate can
be packaged (in an air-tight container) for later use such as, combining
it with an amount of water and directing the diluted product onto a
surface to suppress or retard fire, as described above. The non-aqueous
fire suppressing liquid concentrate can be diluted with water to form a
fire suppression dispersion having from 0.05 to 10 wt % non-aqueous fire
suppressing liquid concentrate in water. The fire suppression dispersion
clings to a surface and forms an intumescent char coating upon fire
contact. The fire suppression dispersion can then be directed toward a
surface to suppress fire. The non-aqueous fire suppressing liquid
concentrate can be diluted on a firefighting vehicle or within
firefighting equipment.

[0032] Thus, embodiments of the NON-AQUEOUS FIRE SUPPRESSING LIQUID
CONCENTRATE are disclosed. The implementations described above and other
implementations are within the scope of the following claims. One skilled
in the art will appreciate that the present disclosure can be practiced
with embodiments other than those disclosed. The disclosed embodiments
are presented for purposes of illustration and not limitation, and the
present invention is limited only by the claims that follow.