U.S. patent application number 15/002254 was filed with the patent office on 2017-07-20 for systems and methods for safely transporting granular material.
The applicant listed for this patent is Transload Equipment, LLC. Invention is credited to Michael Mintz, Ron Wheaton.
Application Number | 20170203917 15/002254 |
Document ID | / |
Family ID | 59314315 |
Filed Date | 2017-07-20 |
United States Patent
Application |
20170203917 |
Kind Code |
A1 |
Mintz; Michael ; et
al. |
July 20, 2017 |
SYSTEMS AND METHODS FOR SAFELY TRANSPORTING GRANULAR MATERIAL
Abstract
Systems and methods are provided for safely and efficiently
transporting granular material. In one embodiment, a method
includes providing an expandable container in an unexpanded state,
expanding the expandable container from the unexpanded state to an
expanded state, and depositing granular material within the
expandable container via an input valve. In this embodiment, the
expandable container includes at least a top plate, a bottom plate,
an outer material coupled to the top and bottom plates, an input
valve associated with the top plate, and a discharge valve
associated with the bottom plate. The expandable container can also
include a containment bladder, for holding the granular material
within the container, and a discharge bladder, for assisting in
discharging the granular material from the container.
Inventors: |
Mintz; Michael; (Corpus
Christi, TX) ; Wheaton; Ron; (Corpus Christi,
TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Transload Equipment, LLC |
Corpus Christi |
TX |
US |
|
|
Family ID: |
59314315 |
Appl. No.: |
15/002254 |
Filed: |
January 20, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B65D 90/046 20130101;
B65D 88/62 20130101; B65D 88/54 20130101; B65D 88/005 20130101 |
International
Class: |
B65D 88/52 20060101
B65D088/52; B65D 90/00 20060101 B65D090/00; B65D 88/08 20060101
B65D088/08; B65D 88/54 20060101 B65D088/54; B65D 88/12 20060101
B65D088/12; B65D 88/30 20060101 B65D088/30 |
Claims
1. A method of safely transporting granular material, comprising:
providing an expandable container in an unexpanded state, the
expandable container comprising: a top plate; a bottom plate; an
outer material; an input valve associated with the top plate; and a
discharge valve associated with the bottom plate, expanding the
expandable container from the unexpanded state to an expanded state
by lifting the expandable container at the top plate; and
depositing granular material within the expandable container via
the input valve.
2. The method of claim 1, wherein depositing the granular material
causes the expandable container to expand while in a lifted
state.
3. The method of claim 1, further comprising discharging granular
material from the expanded container via the discharge valve.
4. The method of claim 3, wherein said discharging causes the
expandable container to return to the unexpanded state.
5. The method of claim 4, further comprising stacking the
expandable container, in the unexpanded state, on top of another
expandable container in an unexpanded state.
6. The method of claim 1, wherein the expandable container
comprises a restraint device removably coupled to the top and
bottom plates and/or support members associated with the top and
bottom plates, and wherein expanding the expandable container
further comprises removing the restraint device.
7. The method of claim 1, wherein the expandable container
comprises a containment bladder coupled to the top and bottom
plates.
8. The method of claim 3, wherein discharging further comprises
inflating a discharge bladder.
9. The method of claim 8, where inflating the discharge bladder
biases the granular material within the containment bladder toward
the discharge valve.
10. An expandable container for safely transporting granular
material, comprising: a top plate; a bottom plate; an outer
material coupled to the top and bottom plates; an input valve
associated with the top plate; and a discharge valve associated
with the bottom plate, wherein the expandable container can be
expanded by applying opposing forces to the top and bottom plates,
respectively.
11. The expandable container of claim 10, further comprising a
containment bladder coupled to the top and bottom plates.
12. The expandable container of claim 10, wherein the outer
material comprises a fabric having at least one of: an elastic
modulus of between about 100 and 200 GPa, or a tensile strength of
between about 2000-4000 MPa.
13. The expandable container of claim 10, wherein the outer
material is coupled to the top and bottom plates via retaining
rings.
14. The expandable container of claim 10, wherein the input valve
and/or discharge valve comprises a spring-loaded plate.
15. The expandable container of claim 10, further comprising a
discharge bladder positioned outside the containment bladder.
16. The expandable container of claim 15, wherein the discharge
bladder is configured to be inflated via an inflation port.
17. The expandable container of claim 16, wherein the discharge
bladder, once inflated, provides a shape that biases the granular
material within the containment bladder toward the discharge
valve.
18. The expandable container of claim 10, further comprising a
restraint device configured to be removably coupled to the top and
bottom plates, thereby preventing the expandable container from
expanding and/or contracting.
19. The expandable container of claim 10, wherein the top and/or
bottom plate further comprises reinforcement members.
20. The expandable container of claim 19, wherein the reinforcement
members of the top and/or bottom plate are coupled to the input
and/or discharge valves, respectively.
Description
DESCRIPTION OF THE EMBODIMENTS
Field of the Embodiments
[0001] The embodiments herein relate generally to systems and
methods for safely transporting granular material, and, more
specifically, to improved systems and methods for safely
transporting granular agricultural and industrial materials such as
cement, barite, and sand for use in hydrocarbon fracking
operations.
BACKGROUND
[0002] Working with certain types of granular material can pose
significant health risks. According to the U.S. Occupational Safety
& Health Administration ("OSHA"), inhalation of small
crystalline silica particles puts workers at risk for silicosis,
lung cancer, chronic obstructive pulmonary disease, as well as
liver, heart, and kidney disease. With the increase of hydraulic
fracturing ("fracking") over the past 5-10 years, the instances of
sicknesses and deaths due to silica inhalation have rapidly
increased. Many fracking sites fail to meet current OSHA standards.
Moreover, OSHA has proposed a new rule lowering the permissible
exposure limit of respirable crystalline silica per cubic meter of
air. This lower limit will impact almost any industry that involves
transporting or otherwise using silica.
[0003] Fracking is a process for stimulating an oil well by
fracturing underground rock using a pressurized liquid. The
pressurized liquid consists primarily of water mixed with a
proppant. A typical proppant is sand, such as "frac sand," although
other granular materials can be used as well. The proppant
functions to maintain an induced hydraulic fracture open such that
the desired oil or gas can be extracted. A single fracking well can
require several thousand tons of frac sand.
[0004] Frac sand is mined and processed in a plant to improve its
performance characteristics. The sand then gets transported from
the plant to the fracking site. This transportation process can
involve trains, ships, trucks, conveyors, and other transportation
methods. Pneumatic pipe systems and conveyors are routinely used to
transport sand from one container to another--for example, from a
rail car to a truck or from a truck to a storage facility.
Pneumatic and conveyor transfers allow silica particles to permeate
the air in the surrounding area, causing a potential health hazard
to any workers nearby.
[0005] In addition to the health hazards, the typical processes for
transporting frac sand have additional drawbacks. For example, a
container (e.g., a rail car or a truck) designed to hold frac sand
may not be useful for carrying other items. That is, once the load
of frac sand has been deposited, the rail car or container cannot
be used for another purpose; instead, it must be returned to a
location where it can be refilled with frac sand. The lack of
reusability increases transportation costs and, as a result, the
overall cost of fracking.
[0006] Therefore, a need exists for systems and methods for safely
and efficiently transporting granular material. More specifically,
a need exists for systems and methods for transporting granular
material in a manner that limits respirable silica emissions,
eliminates harmful pneumatic transfers, and provides lower
transport costs.
SUMMARY
[0007] Embodiments described herein include systems and methods for
safely and efficiently transporting granular material. In one
embodiment, a method includes providing an expandable container in
an unexpanded state, expanding the expandable container from the
unexpanded state to an expanded state, and depositing granular
material within the expandable container via an input valve. In
this embodiment, the expandable container includes at least a top
plate, a bottom plate, an outer material coupled to the top and
bottom plates, an input valve associated with the top plate, and a
discharge valve associated with the bottom plate. The expandable
container can also include a containment bladder for holding of the
granular material within the container and protecting it from the
elements, and a discharge bladder for assisting in discharging the
granular material from the container.
[0008] In another embodiment, the method also includes transporting
the expandable container. The method can further include
discharging granular material from the expanded container via the
discharge valve. The discharge bladder may be inflated in a manner
that urges or biases the granular material within the containment
bladder toward the discharge valve. Discharging the granular
material may cause the expandable container to return to its
unexpanded state. Once in its unexpanded state, the expandable
container may be stacked on top of a similar expandable container,
also in an unexpanded state, for transporting. This can, for
example, require half or fewer train cars to return the expandable
containers than is needed for transporting the full containers.
[0009] In one embodiment, the expandable container includes a
restraint device removably coupled to the top and bottom plates
and/or support members associated with the top and bottom plates.
Expanding the expandable container may include the step of removing
the restraint device.
[0010] In yet another embodiment, an expandable container is
provided for safely transporting granular material. The expandable
container can include a top plate, a bottom plate, an outer
material coupled to the top and bottom plates, an input valve
associated with the top plate, and a discharge valve associated
with the bottom plate. Furthermore, the expandable container can be
expanded by applying opposing forces to the top and bottom plates,
respectively.
[0011] The expandable container may include a containment bladder
coupled to the top and bottom plates. The outer material may
include at least one Kevlar or Kevlar-reinforced band, and/or may
be coupled to the top and bottom plates via retaining rings. The
input valve and/or discharge valve may include a spring-loaded
plate. A discharge bladder may be included, and can be positioned
outside the containment bladder and inside the outer material. The
discharge bladder can be configured to be inflated via an inflation
port. Once inflated, the discharge bladder can provide a shape that
biases the granular material within the containment bladder toward
the discharge valve.
[0012] The expandable container can also include a restraint device
that can be removably coupled to the top and bottom plates, thereby
limiting the vertical expansion of the container. The top and/or
bottom plates of the expandable container can also include
reinforcement members. These reinforcement members can be coupled
to the input and/or discharge valves, respectively.
[0013] Both the foregoing general description and the following
detailed description are exemplary and explanatory only and are not
intended to restrict the scope of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The accompanying drawings, which are incorporated in and
constitute a part of this disclosure, illustrate various
embodiments and aspects of the present invention. In the
drawings:
[0015] FIG. 1 is an illustration of an example embodiment of an
expandable container for transporting granular material;
[0016] FIG. 2 is a cross-sectional view of an example embodiment of
an input valve of an expandable container;
[0017] FIG. 3 is a cross-sectional view of an example embodiment of
an expandable container having a discharge valve and discharge
bladder;
[0018] FIG. 4A is an illustration of an example embodiment of an
expandable container in an unexpanded state;
[0019] FIG. 4B is an illustration of an example embodiment of an
expandable container in an expanded state; and
[0020] FIG. 5 is a flow chart of an example method of transporting
granular material using an expandable container.
DETAILED DESCRIPTION
[0021] Reference will now be made in detail to the present
exemplary embodiments, including examples illustrated in the
accompanying drawings. Wherever possible, the same reference
numbers will be used throughout the drawings to refer to the same
or like parts.
[0022] The expandable containers described herein may be used to
store and transport granular material, such as frac sand. In one
example embodiment, the expandable container may have a containment
volume of about 500 cubic feet. In that example the expandable
container may be about 10 feet tall in its expanded state and have
a diameter of about 8 feet. The height and diameter, and therefore
the containment volume, of the container may be varied according to
the particular transportation needs of a project. For example, the
container may have an expanded height of between 6-14 feet, and may
have a diameter of between 4-12 feet. Other sized may be used as
well, and these examples are not intended to limit this disclosure
in any way.
[0023] FIG. 1 is an illustration of an example embodiment of an
expandable container 100 for transporting granular material. The
expandable container includes a top plate 110 and bottom plate 120,
with an outer material 130 coupled to the top and bottom plates
110, 120. The top and bottom plates 110, 120 may be constructed
from a rigid material, such as steel or other metals and alloys.
The outer material 130 can be coupled to the top and bottom plates
110, 120 via locking rings 150. Locking rings 150 secure the outer
material 130 to the top and bottom plates 110, 120 by applying a
clamping force. Locking rings 150 may fit flush with the side of
the top and/or bottom plates 110, 120, or may fit at least
partially inside a slot provided in the top and/or bottom plates
110, 120. Locking rings 150 may be tightened by mechanical means to
a tension sufficient to retain the outer material 130 during
use.
[0024] The outer material 130 can be constructed from a robust yet
flexible material such as, for example, Kevlar or other material
having similarly high elastic modulus and/or tensile strength
measurements. For example, the outer material 130 can be made from
a fabric having an elastic modulus of between about 100 and 200
GPa. In some examples, the outer material 130 can be made from a
material having a tensile strength of between about 2000 and 4000
MPa. In other examples, material having characteristics outside of
these ranges can be used. However, a material with these
characteristics can prevent bulging and thereby maintain the
uniform cross-sectional diameter of the container as the outer
material. The outer material 130 functions to contain the contents
of the expandable container 100, including any internal bladders or
containment vessels. The outer fabric material 130 can be stronger
than steel, on a per-weight basis. However, it also provides
flexibility such that the expandable container 100 can be expanded
or contracted in an efficient and reliable manner. At the same
time, however, the outer material 130 is strong enough to resist
tearing or rupturing during use, which may involve heavy machinery
and large forces or loads.
[0025] For increased strength and overall robustness of the
container, support members 160 may be coupled to the top plate 110
and/or bottom plate 120. The support members 160 provide increased
rigidity of the top and bottom plates 110, 120, and enable multiple
expandable containers 100 to be stacked on top of one another. The
support members 160 also provide a mechanism to manipulate the
expandable container 100 itself. For example, the loading process
may require the top plate 110 to be lifted and/or vibrated to
efficiently fill the containment volume with granular material. In
this scenario the top plate 110 can be gripped via support members
160 and manipulated as needed. The container 100 can be filled with
sand while lifted, allowing the weight of the sand to expand the
container 100 downward. Then the full container 100 can 100 can be
placed on a train car or other transport.
[0026] Additionally, support members 160 can be used to temporarily
fix the height of the expandable container 100. As discussed
further with respect to FIG. 4A, the support members 160 can be
connected via an additional member that limits the expansion or
contraction abilities of the expandable container 100 while
connected. Finally, the support members 160 may also be coupled to
the input valve 140 and/or discharge valve, as discussed in more
detail below.
[0027] With respect to FIG. 1, a discharge bladder valve 170 is
also shown. The discharge bladder valve 170 can be used to provide
fluid, such as compressed air, to one or more discharge bladders
inside the expandable container 100. This functionality is
discussed in more detail below with respect to FIG. 3.
[0028] FIG. 2 is a cross-sectional view of an example embodiment of
input valve 140. The same architecture and components may be used
for a discharge valve as well--therefore, any reference herein with
respect to an "input" valve, or its components, may be applied in
similar fashion to a discharge valve. FIG. 2 shows a support member
160 coupled to both the top plate 110 and the input valve 140. The
support member 160 may be coupled to the top plate 110 via
fasteners or welds along the length, or a portion of the length, of
the support member 160. The support member 160 may be coupled to
the input valve 140 via valve shaft 220. Valve shaft 220 can be
provided as a solid or hollow bar of metal or other high-strength
material in order to provide a solid base upon which the input
valve 140 functions. The support member 160 can be coupled to valve
shaft 220 by welding, fastening, or other mechanical connection
techniques.
[0029] A valve plate 210 can be used to control the flow of
material into or out of a valve. The valve plate 210 can be
provided as a circular disk with a hole that accommodates valve
shaft 220, such that the valve plate 210 can slidably move along
the valve shaft 220. A biasing mechanism, such as a spring 240, can
be used along at least a portion of the valve shaft 220. Spring 240
biases the valve plate 210 in a manner that will cause the valve
plate 210 to sit flush with the top plate 110 in its resting
position (i.e., when no external forces are being applied to the
valve plate 210). A valve pin 230 can be provided along the valve
shaft 220 to abut one end of the spring 240, while the other end of
the spring 240 abuts the valve plate 210.
[0030] To operate the input valve 140, the valve plate 210 is
depressed such that it moves along the valve shaft 220 toward the
valve pin 230, compressing the spring 240. In practice, the valve
plate 210 can be depressed by a loading apparatus. For example, the
nozzle of a hopper, tube, or pipe carrying granular material can be
shaped to contact and depress the valve plate 210. In some
embodiments one mechanism is used to depress the valve plate 210
while a separate component provides the granular material. Any
device that depresses the valve plate 210 toward the valve pin 230
can be used to open the input valve 140.
[0031] As mentioned above, a discharge valve may incorporate the
same, or similar, components described in FIG. 2 with respect to
the input valve 140. FIG. 3 shows a cross-sectional view of an
example embodiment of an expandable container having a discharge
valve 320 and discharge bladder 340. Similar to the input valve 140
described with respect to FIG. 2, the discharge valve 320 of FIG. 3
includes a valve shaft 322, valve plate 324, valve pin 328, and a
spring 326. The discharge valve 320 is operated by depressing or
otherwise moving the valve plate 324 along the valve shaft 322
toward the valve pin 328, compressing the spring 326 and exposing
an opening in the bottom plate 310. The discharge valve 320 of FIG.
3 is shown in an open position, where the granular material 350 may
freely flow out.
[0032] FIG. 3 also shows a containment bladder 330 having an amount
of granular material 350. The containment bladder 330 is located
within the outer material 130 and may be constructed from a
gas-impermeable membrane, such as nylon. Other materials may be
used as well. Suitable materials include any material that is
sufficiently pliable and strong, and does not allow any granular
material, dust, or gases to escape through the material. The
containment bladder 330 can be coupled to the outer material 130,
support members 160, or the top and/or bottom plates 110, 310. In
the embodiment depicted in FIG. 3, the containment bladder 330 is
coupled to at least the bottom plate 310.
[0033] FIG. 3 also shows discharge bladder 340. Discharge bladder
340 is shown in two portions in FIG. 3--each portion roughly
triangular in cross section. These two portions represent a
cross-sectional view of a single discharge bladder 340 that wraps
around the expandable container 100. In this embodiment the
discharge bladder 340 is one bladder; however, in other embodiments
the discharge bladder 340 may include multiple bladders working in
combination with one another. In either case, the bladders may be
inflated with a fluid, such as air or another gas, via discharge
bladder valve 170.
[0034] Discharge bladder 340 can be inflated during the discharge
process when the granular material 350 begins to run low. One
purpose of the discharge bladder 340 is to prevent granular
material 350 from remaining trapped inside the containment bladder
330 due to the flat-bottomed shape of the expandable container 100.
Discharge bladder 340 fills in the areas that may trap the granular
material 350, thereby urging the remaining granular material 350 to
exit the discharge valve 320.
[0035] Discharge bladder 340 may inflate automatically, for example
by using input from a sensor that determines the amount of granular
material 350 remaining in the expandable container 100. In this
embodiment discharge bladder 340 may be connected to a built-in
pump provided within, or attached to, the expandable container 100.
In other embodiments the discharge bladder 340 can be inflated
manually by attaching an air hose to the discharge bladder valve
170.
[0036] FIGS. 4A and 4B each show an expandable container 100
similar to the container of FIG. 1. The expandable container 100 in
FIG. 4A is shown in a collapsed or unexpanded state, whereas the
expandable container 100 in FIG. 4B is shown in an expanded state.
FIGS. 4A and 4B also show a restraint device 410 that can be
coupled to at least one support member 160. Although only a single
restraint device 410 is shown, multiple may be used. When the
restraint device 410 is secured to two support members 160
associated with the top and bottom plates 110, 120, respectively
(as shown in FIG. 4A), the expandable container 110 is prevented
from expanding.
[0037] The unexpanded state of FIG. 4A can be useful for
transporting empty containers 100 in an efficient manner. For
example, thirty trucks may be sent to a worksite, with each truck
carrying two expandable containers 100 filled with granular
material. After depositing the granular material at the worksite,
the expandable containers 100 can be secured in their unexpanded
states via restraint device 410 and stacked three containers high,
such that all sixty containers can be loaded onto ten trucks. This
lowers the transportation cost associated with transporting
granular material.
[0038] To prepare the expandable container 100 of FIG. 4A for
loading, the restraint device 410 can be decoupled from one of the
support members 160. As shown in FIG. 4B, for example, the
restraint device 410 can be decoupled from a support member 160
associated with the bottom plate. In order to secure the restraint
device 410 when it is only attached to one support member 160, a
restraint strap may be provided along the side of the expandable
container 100. For example, the restraint strap may be attached to
the outer material 130.
[0039] FIG. 5 provides a flow chart of an example method of
transporting granular material using the expandable containers
described herein. At step 510, an expandable container is provided.
In the embodiment of FIG. 5, the container is provided in an
unexpanded state; however, the container may be provided in either
an expanded or unexpanded state at this step.
[0040] If a restraint device is installed such that the container
is prevented from expanding, the restraint device is removed at
step 520.
[0041] At step 530, the expandable container is expanded. This may
involve, for example, lifting the expandable container using the
top plate, or support members attached to the top plate, and
allowing the container to expand via the weight of the bottom
plate. This step may also involve some amount of vibration or
movement to encourage the container to expand sufficiently.
[0042] At step 540, granular material is deposited into the
expandable container via an input valve. This step may occur
simultaneously with step 530, or may occur after step 530. For
example, when the expandable container is lifted from the top
plate, pouring sand into the lifted container can provide enough
weight to cause the bottom of the container to expand downward.
Step 540 includes accessing the input valve by depressing the valve
plate, as described with respect to FIG. 2. This step also includes
supplying granular material to the expandable container, for
example by using a hopper, conduit, hose, funnel, or other device
that directs the granular material into the input valve. The device
supplying the granular material may also depress the valve plate,
or these actions may be done separately by two different
devices.
[0043] Step 540 may also include vibrating or otherwise applying
force to the expandable container as the granular material is
deposited. The application of force spreads the granular material
within the expandable container and allows for an uninterrupted
flow of material into the container.
[0044] At step 550, the filled expandable container is transported
to its destination. Because a filled container can be quite heavy,
machinery may be used to lift the filled container and place it on
a truck, ship, train car, or other transportation device. In some
embodiments, the same machinery is used to expand the container at
step 530 and load the container at step 550. In other embodiments
separate machines are used at each step.
[0045] At step 560, the granular material is discharged from the
expandable container at its desired location. Depending on the type
of transport vehicle used, the filled containers may need to be
removed from the transport vehicle before the granular material is
discharged. To discharge the material, the container is positioned
in the desired location and the valve plate of the discharge valve
is depressed, as shown in FIG. 3. This opens the valve and allows
material to flow from the container.
[0046] Step 570 includes inflating the discharge bladder (or
bladders, if the container is equipped with more than one) such
that any remaining granular material is expelled through the
discharge valve. As described with respect to FIG. 3, the discharge
bladder may inflate automatically based on a perceived level of
material in the container, or may be inflated manually by, for
example, attaching a source of compressed air to the discharge
bladder valve.
[0047] At step 580, the now-empty expandable container is provided
in an unexpanded state due to its lack of contents. At this step
the restraint device may be installed, or reinstalled, such that it
connects to at least one support member along the top plate and one
support member along the bottom plate. Once secured, the restraint
device maintains the unexpanded geometry of the container. This
allows for multiple unexpanded containers to be stacked on top of
one another--for example, on a truck or other shipping vehicle.
Once the unexpanded containers are returned to the storage location
for the granular material, they may be filled again starting with
Step 510.
[0048] Other embodiments of the invention will be apparent to those
skilled in the art from consideration of the specification and
practice of the invention disclosed herein. It is intended that the
specification and examples be considered as exemplary only, with a
true scope and spirit of the invention being indicated by the
following claims.
* * * * *