U.S. patent application number 10/778707 was filed with the patent office on 2004-11-18 for formulation for dust abatement and prevention of erosion.
Invention is credited to Lloyd, Christopher T., Schultz, Warren W., Spargo, Barry J., Wynne, James H..
Application Number | 20040227126 10/778707 |
Document ID | / |
Family ID | 33424111 |
Filed Date | 2004-11-18 |
United States Patent
Application |
20040227126 |
Kind Code |
A1 |
Wynne, James H. ; et
al. |
November 18, 2004 |
Formulation for dust abatement and prevention of erosion
Abstract
A safe, biodegradable, environmentally benign, non-toxic,
water-soluble solution consisting of water, sugar, starch, sodium
phosphate, and surfactant that can be applied to dust and sand
particles to bind the particles and form a hardened crust. Also
disclosed is the related method for abating dust and preventing
erosion.
Inventors: |
Wynne, James H.;
(Alexandria, VA) ; Spargo, Barry J.; (Baltimore,
MD) ; Lloyd, Christopher T.; (Springfield, VA)
; Schultz, Warren W.; (Edgewater, MD) |
Correspondence
Address: |
NAVAL RESEARCH LABORATORY
ASSOCIATE COUNSEL (PATENTS)
CODE 1008.2
4555 OVERLOOK AVENUE, S.W.
WASHINGTON
DC
20375-5320
US
|
Family ID: |
33424111 |
Appl. No.: |
10/778707 |
Filed: |
February 12, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60471445 |
May 16, 2003 |
|
|
|
Current U.S.
Class: |
252/88.1 |
Current CPC
Class: |
C09K 2105/00 20130101;
C09K 17/40 20130101; C09K 3/22 20130101 |
Class at
Publication: |
252/088.1 |
International
Class: |
C09K 003/22 |
Claims
What is claimed:
1. A composition of matter suitable for dust and sand abatement and
prevention of erosion, comprising: (a) between about 1 and 70%
(w/w) sugar; (b) between about 0 and 70% (w/w) of a polysaccharide;
(c) between about 0 and 30% (w/w) phosphate; (d) between about 0
and 30% (w/w) of a surfactant; and (e) between about 20 and 99%
(w/w/) water; wherein when said composition of matter is applied to
sand or dust particles, the composition of matter binds to the sand
or dust particles and forms a hardened crust.
2. The composition of matter of claim 1, wherein said sugar is
selected from the group consisting of sugar, syrup, corn syrup, and
combinations thereof.
3. The composition of matter of claim 1, wherein said sugar is
selected from the group consisting of monosaccharides,
disaccarides, and combinations thereof.
4. The composition of matter of claim 1, wherein said
polysaccharide is starch.
5. The composition of matter of claim 1, wherein said surfactant is
selected from the group consisting of soaps, quaternary ammonium
salts, and combinations thereof.
6. The composition of matter of claim 1, wherein said phosphate is
selected from the group consisting of sodium phosphate, detergents
containing phosphate, and combinations thereof.
7. The composition of matter of claim 1, comprising 24% (w/w)
sugar, 15% polysaccharide, 0.1% (w/w) sodium phosphate, 0.03% (w/w)
of a surfactant, and 61% (w/w) water.
8. The composition of matter of claim 7, wherein said
polysaccharide is starch and said surfactant is a soap.
9. The composition of matter of claim 1, additionally comprising up
to 1% of a biocide, a fungicide, or combinations thereof.
10. A method for dust and sand abatement and preventing erosion,
comprising the steps of: (a) preparing a solution comprising
between about 1 and 70% (w/w) sugar, between about 0 and 70% (w/w)
of a polysaccharide, between about 0 and 30% (w/w) phosphate,
between about 0 and 30% (w/w) of a surfactant, and between about 20
and 99% (w/w) water; (b) applying the solution to sand or dust
particles wherein the solution binds to the particles; and (c)
allowing the sand or dust particles to dry thereby forming a
hardened crust.
11. The method of claim 10, wherein said sugar is selected from the
group consisting of solid sugar, syrup, corn syrup, and
combinations thereof.
12. The method of claim 10, wherein said sugar is selected from the
group consisting of monosaccharides, disaccarides, and combinations
thereof.
13. The method of claim 10, wherein said polysaccharide is
starch.
14. The method of claim 10, wherein said surfactant is selected
from the group consisting of soaps, quaternary ammonium salts, and
combinations thereof.
15. The method of claim 10, wherein said phosphate is selected from
the group consisting of sodium phosphate, detergents containing
phosphate, carbonates, sulfonates, and combinations thereof.
16. The method of claim 10, wherein said composition comprises 24%
(w/w) sugar, 15% polysaccharide, 0. 1% (w/w) sodium phosphate,
0.03% (w/w) of a surfactant, and 61% (w/w) water.
17. The method of claim 16, wherein said polysaccharide is starch
and said surfactant is a soap.
18. The method of claim 10, wherein said solution additionally
comprises up to 1% of a biocide, a fungicide, or combinations
thereof.
19. The method of claim 10, wherein said solution is applied by
using a hand held bottle sprayer, a garden sprayer, a pump sprayer,
a hydro-seeder, an agricultural sprayer, a fire truck, an aircraft
sprayer, or any combination thereof.
Description
PRIORITY CLAIM
[0001] The present application claims priority from U.S.
Provisional Application No. 60/471,445 filed May 16, 2003, entitled
"FORMULATION FOR DUST ABATEMENT AND PREVENTION OF EROSION"
(attorney docket number 84,722), the entire contents of which are
incorporated herein by reference.
BACKGROUND
[0002] 1. Field of the Invention
[0003] The present invention relates to dust abatement and, more
specifically, to a crust-forming aqueous solution that aids in the
abatement of dust and sand and in the prevention of wind
erosion.
[0004] 2. Description of the Related Art
[0005] Dust abatement issues have been a major concern for the U.S.
military dating as far back as World War II. To date,
polyacrylamide (PAM) is used as a soil stabilizer on roads and
airfields to reduce the amount of airborne dust and sand particles.
More recently, there have been several incidents involving the hard
decking of military aircraft as a result of limited visibility due
to dust and airborne sand brownouts. Tests have been performed
utilizing PAM and were successful in a few cases; however, there
are several major concerns with the application of PAM. The
quantity of water required to effectively apply PAM is a concern,
especially in desert environments. The well-documented carcinogenic
properties associated with its residual monomer, acrylamide, which
is contained within, are an even greater cause for attention. Also,
the application of PAM can be a very labor-intensive operation.
These concerns suggest the need for a much safer more environmental
solution that would be less of a logistical burden.
[0006] The use of PAM for reduction of irrigation-induced erosion
has also increased in recent years; however, its toxicity and
environmental fate in this application remains a concern. PAM is a
water-soluble, high molecular weight, synthetic organic polymer
that interacts with the clay found in some soils. The interaction
depends upon the properties of the polymer as well as the
characteristics of the soil. It is effective in stabilizing soil
aggregates, reducing soil erosion, increasing water infiltration,
and also has an indirect positive impact upon crop growth and
yield. In general, PAM degradation occurs through physical
breakdown. PAM itself has been shown to be non-toxic to animals,
fish and plants; however, the toxicity of its residual monomer
(acrylamide) is a known neurotoxin to humans. The major source of
acrylamide that is released into the environment is from the use of
polyacrylamide products. As a result of such use, FDA regulates the
content of PAM and its residual monomer present in food products.
See C. A. Seybold, Communications in Soil Science and Plant
Analysis 1994, 25, 2171-2185 and D. J. King, R. R. Noss, Reviews on
Environmental Health 1989, 8, 3-16, both of which are incorporated
herein by reference. 1
Structure of Polyacrylamide (PAM)
[0007] PAM has been shown to be very effective in controlling water
erosion from furrow irrigation. Laboratory and field wind tunnel
tests using several formulations and rates of PAM were reported to
determine its possible use for forming wind erosion-resistant
surfaces (crusts). These tests showed that PAM was no more
effective than natural rainfall for wind erosion control within
general agricultural conditions. See D. V. Armburst, Journal of
Soil and Water Conservation 1999, 54, 557-559, incorporated herein
by reference.
[0008] Research has also been performed to optimize the binding
ability of PAM to various types of clay minerals. It was determined
that the efficacy of cationic and anionic PAM increased
effectiveness of dispersed clays; however, the non-neutral pH
materials pose additional environmental and health concerns. See D.
A. Laird, Soil Science 1997, 162, 826-832, incorporated herein by
reference.
[0009] Use of PAM for the reduction of pesticide contamination
through runoff from agricultural fields and wind erosion-resistant
surfaces has also been studied. The formation of the crust has been
reported to retain moisture in the sand/soil and prevent rapid
evaporation in arid conditions. See G. Singh, J. Letey, P. Hanson,
P. Osterli, & W. F. Spencer, Journal of Environmental Science
Health Part B 1996, 31, 25-41, incorporated herein by
reference.
[0010] The application of PAM in landing zone environments is a
multi-step process. The procedure generally starts by an initial
application of water followed by an application of a select
sorbent. The sorbent is then mixed into the soil/sand by agitation.
Typically, this technique employs such instruments as a garden hoe
or a leaf rake. After mixing, an additional application of water is
made followed by treatment with polyacrylamide, which is typically
applied in the form of a high molecular weight solid ground
polymer. Due to the toxicity of residual monomer present in the PAM
polymer mixture, special personal protective equipment must be
utilized by those handling the material in fine powder form. Also,
aired conditions promote sublimation of residual monomer, which
again poses a health concern to the end users. This is yet again
manually mixed into the soil, and a final application of water is
made to complete the process.
[0011] The use of sugar has been noted in multiple commercial
applications; however, there are few reports that are relevant.
Patents for formulations involving sugar have been utilized to
prevent fertilizer granule caking (see, e.g., U.S. Pat. No.
5,328,497 to Hazlett, which is incorporated herein by reference)
and to reduce dust formation from detergent tablets (see, e.g.,
U.S. Pat. No. 6,376,454 to Eggersmann et al., which is incorporated
herein by reference). In addition, a polysaccharide comprising of
at least nine monosaccharide units suspended in an oil base with
thickeners and emulsifiers has been used for dust suppression (see,
e.g., U.S. Pat. No. 5,595,782 to Cole, which is incorporated herein
by reference).
[0012] Other products such as emulsions of polyvinyl acetate and
esters of polyvinyl alcohols have been reported to effectively
promote surface consolidation of soil and cements. See J. M. Geist,
S. V. Amagna, B. B. Mellor, Industrial and Engineering Chemistry
1953, 45, 759-767 and U.S. Pat. No. 6,122,860 to Von Tapavicza et
al., both of which are incorporated herein by reference. To a
lesser degree various foaming agents functioning as elastomeric
insoluble polymers have also been utilized in dust suppression
(see, e.g., U.S. Pat. No. 4,551,261 to Salihar, which is
incorporated herein by reference). Partly olefinically unsaturated
fatty acids of triglycerides as biodegradable plasticizers in
dispersions have been utilized for surface stabilization of sand
and soil (see, e.g., U.S. Pat. No. 5,846,601 to Ritter et al.,
which is incorporated herein by reference). Various compositions
consisting of primarily lignin sulfonate have been demonstrated to
stabilize soil formations from the effects of water (see, e.g.,
U.S. Pat. No. 4,394,213 to Ferm, which is incorporated herein by
reference).
[0013] With the aforementioned documented problems and limited
scope, there is clearly a need for an aqueous formulation that is
environmentally friendly and can be easily applied in a single step
for the purpose of dust abatement and prevention of wind
erosion.
SUMMARY
[0014] The aforementioned problems of the current technology are
overcome by the present invention wherein a safe, biodegradable,
environmentally-benign, non-toxic, water-soluble solution can be
applied to dust and sand to bind the particles forming a hardened
crust top layer. The solution consists of a mixture of water,
sugar, starch, sodium phosphate, and soap/surfactant. Once applied,
the wetted layer dries to form a wind erosion-resistant surface
(crust). Upon formation of the hardened crust and times prior
thereto, binding occurs insomuch as to be effective immediately
upon application. Heat and windy conditions promote the
effectiveness of this product.
[0015] According to a preferred embodiment, a composition of matter
suitable for dust abatement and prevention of erosion comprises
between about 1 and 70% (w/w) sugar, between about 0 and 70% (w/w)
of a polysaccharide, between about 0 and 30% (w/w) phosphate,
between about 0 and 30% (w/w) of a surfactant, and between about 20
and 99% (w/w) water, wherein when the said solution is applied to
sand or dust particles, the solution binds to the sand or dust
particles and forms a hardened crust. Another embodiment of the
present invention is a method for abating dust and preventing
erosion, comprising the steps of (a) preparing a solution
comprising between about 1 and 70% (w/w) sugar, between about 0 and
70% (w/w) of a polysaccharide, between about 0 and 30% (w/w)
phosphate, between about 0 and 30% (w/w) of a surfactant, and
between about 20 and 99% (w/w) water; (b) applying the solution to
sand or dust particles wherein the solution binds to the particles;
and (c) allowing the sand or dust particles to dry thereby forming
a hardened crust.
[0016] The present invention has several advantages over existing
technology and current techniques, including the following: it is
environmentally friendly; it is a simple, one-step application; it
is non-toxic, non-flammable, and biodegradable; it is cost
effective; it requires less water than other dust palliatives; it
has increased binding strength over PAM and other products; it is
easy to prepare and apply; desert conditions increase its
effectiveness; it is immediately effective upon application; it is
effective on a variety of particle sizes ranging from less than 1
Jim to greater than 500 .mu.m; it is effective on a variety of
types of dusts and sands, including silicas, clays and carbonates;
it has increased shelf-life; it will not harden nor degrade in
solution form upon storage; and it withstands generated wind shear
up to 50 psf.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] In a preferred embodiment, an optimum highly effective
solution consists of a mixture of 24% (w/w) sugar (sucrose), 15%
(w/w) starch, 0.1% (w/w) sodium phosphate, 0.03% (w/w)
soap/surfactant (e.g. Dawn.RTM.), and 61% (w/w) water. The sugar
and the water are the primary active ingredients within the
solution. The concentrations of these components within the mixture
may be varied while maintaining effectiveness of the solution,
within the ranges listed below. Additionally, a small amount (<1
%) of a biocide, fungicide, or combination of biocide and fungicide
may be added to enhance storage stability. The application of the
described solution is effective at temperature ranges from 0 to
150.degree. F.
[0018] The solution may consist of 20 to 99% (w/w) water.
[0019] The sugar content in the solution may range from 1 to 70%
(w/w). The sugar can be in a solid form or a liquid form (e.g.,
syrup or corn syrup). Several alternatives in part or in whole, may
be substitutes for the sugar (sucrose) in the mixture. Any form of
a monosaccharide (e.g. glucose, fructose) or disaccharide (e.g.
maltose) may be substituted for the sugar in the solution while
obtaining similar binding effects.
[0020] The percent starch in the solution may range from 0 to 70%
(w/w). Any form of a polysaccharide (e.g. cellulose) may be
substituted for the starch without decrease in the effectiveness of
the solution.
[0021] The concentration of soap may be varied from 0 to 30% in the
solution (functioning as a surfactant). Similar surfactants
including, but not limited to, any quaternary ammonium salt or
mixture there of, may be substituted for the soap.
[0022] The sodium phosphate concentration may be varied from 0 to
30% in the solution mixture. This additive may function as a
mordant and may be substituted for other similar compounds, such as
automatic detergent, laboratory glassware detergent, carbonates,
phosphates or other sulfates.
[0023] Studies involving varying the concentrations of each of the
components within the solution were performed to examine
effectiveness. Solutions were applied to sand of various
compositions and particle sizes. Particle sizes ranged from <1
.mu.m to >500 .mu.m. Sand compositions consisted of carbonate,
silica, clay, mixes and others. Application was made using hand
held bottle sprayers, garden sprayers, hydro-seeders, an
agricultural sprayer, commercial and military automated pump
sprayers, fire trucks, and combinations thereof. The sand was
allowed to dry in ambient conditions with times ranging from 1
second to 48 hours. Hardening of surface was increased with
prolonged drying times, increased temperature, decreased humidity,
or combinations thereof.
[0024] For purposes of reducing occurrences involving helicopter
hard decking due to brownouts, tests were performed in ambient
outdoor conditions using a high-velocity wind-generating fan. Three
feet by three feet areas of sand were prepared and the described
solution was applied. Various surfaces were examined to include
groomed and rough terrain and hills. Upon complete drying and
hardening, top crusts were formed with varying thickness depending
upon volume of solution applied. The solution may be applied in
volumes ranging from 1 mL to 20 liters per square foot. The wind
generator was placed directly over the sand. The generated wind
speed was varied from speeds of 5,000 rpm to 15,000 rpm. Heavy-lift
military helicopters are known to produce downwind forces
equivalent to 7,500 rpm upon landing and take-off.
[0025] Experimental Details
[0026] General Procedure for Preparation of the Embodied
Solution
[0027] In this example, commercial materials were employed in the
preparation of the described solution. To a 4 L beaker equipped
with magnetic stirrer were added 2 L of water and 800 grams of
sugar (sucrose). While stirring at a rate of 870 rpm, at room
temperature, the sugar was allowed to dissolve over a period of
about 5 minutes. The solution became homogeneous prior to the
addition of 0.5 liters of starch, 3 grams of sodium phosphate, and
1 gram of liquid dishwashing soap/surfactant (a 15% aqueous
cetyldimethylethylene ammonium bromide (CDEAB) solution). The
resulting solution was allowed to stir for an additional 10 minutes
to ensure complete mixing.
[0028] General Procedure for Application and Evaluation
[0029] The formulated solution was placed in a 32-ounce spray
bottle and applied to a variety of sands with varying particle
sizes. The sand was allowed to dry in ambient conditions with times
ranging from 1 seconds to 48 hours. Hardening was increased with
prolonged periods of drying and/or addition of heat. Surface
hardness tests were performed during the drying process by applying
weight in excess of 10 pounds to four-inch by four-inch areas of
the top crust layer of the treated sand. As a result, the crust
withstood the force applied, 90 psf, with no visible signs of
disturbance to the treated layer.
[0030] Tests were performed outdoors using a high-velocity wind
generator. Conditions for these tests ranged from 65 to 80.degree.
F. with 10 to 20% relative humidity. Three feet by three feet (9
ft.sup.2) areas of sand with various particle sizes were treated
with 50 mL of the formulated solution using a 2-gallon garden
sprayer. The wind generator was placed directly over the sand/dust
and speed ramped from a velocity of 5,000 rpm, generating 10 psf,
to 15,000 rpm, generating 50 psf.
[0031] Currently, heavy-lift military helicopters are known to
produce downward wind forces of approximately 17 psf, (.about.7,500
rpm) during take-off and landing. This confirms that the formulated
solution is very effective in such applications as preparing
landing zones for heavy-lift military helicopters. Reapplication to
broken surfaces also proved successful.
[0032] Because the formulated solution is effective for situations
where high velocity wind forces are introduced, a direct parallel
can be drawn (extrapolated) to include the utility of this product
in agricultural applications, where wind erosion prevention is
needed.
[0033] After successful laboratory experimentation, a field test
was conducted in a desert area of the Marine Corps Air Station in
Yuma, Ariz. A landing zone area was designated 200 feet by 200
feet, and then subdivided into two areas, thus creating two 100
feet by 200 feet areas. In both cases, the solution was premixed by
agitation in a 700-gallon water bladder and then subsequently
sprayed onto the desert floor/surface. A 3.5 horsepower gasoline
powered garden pump was used to supply the prepared solution
through two 11/2-inch flexible water hoses. The spray guns employed
were connected to the flexible water hose using a threaded PVC
adapter. The dimensions of this apparatus employed for this case
was a 11/2 inch PVC pipe with cutoff valve and a terminal reducing
coupling to 1 inch at the exit point.
EXAMPLE 1
[0034] On one area, a dilute formulation was applied. The dilute
formulation consisted of 1,200 pounds granulated sugar, 250
milliliter dishwashing liquid, 1 pound phosphate salt, 150 pound
starch and 1200 gallons of water.
EXAMPLE 2
[0035] In the second area, the formulation consisted of a more
concentrated formulation. The more concentrated formulation
consisted of 1,200 pounds granulated sugar, 250 milliliters
dishwashing liquid, 1 pound phosphate salt, 150 pound starch and
400 gallons of water.
[0036] In both examples, the results were excellent. Within minutes
of application and evaporation of the water, a solid hardened crust
formed. The following day, helicopters landed on both of the test
sites multiple times with almost complete reduction of airborne
sand and dust. Even the areas of the surface that were damaged by
the landing gear and/or landing wheels automatically self-healed to
regenerate a top hardened surface. Various military helicopters
performed landings, touch-and-goes, and hovering maneuvers the
following day with equal success.
[0037] Examples 3 and 4 below describe additional field testing
that was done using corn syrup as the sugar. Again, the results
were excellent with a solid hardened crust forming within minutes
of application and evaporation of the water.
EXAMPLE 3
[0038] The solution consisted of 130 gallons of corn syrup, 4
pounds phosphate salt, 2.5 gallons liquid starch, 300 mL of liquid
soap and 865 gallons of water.
EXAMPLE 4
[0039] The solution consisted of 130 gallons of corn syrup, 4
pounds phosphate salt, 2.5 gallons liquid starch, 300 mL of liquid
soap and 1265 gallons of water.
[0040] The above description is that of a preferred embodiment of
the invention. Various modifications and variations are possible in
light of the above teachings. It is therefore to be understood
that, within the scope of the appended claims, the invention may be
practiced otherwise than as specifically described. Any reference
to claim elements in the singular, e.g. using the articles "a,"
"an," "the," or "said" is not construed as limiting the element to
the singular.
* * * * *