SYSTEMS FOR AUTOMATED CAPTURE AND RECOVERY OF OIL FROM OIL-CONTAMINATED WATER AND SOLIDS

Abstract

Systems for automated capture and recovery of oil from oil-contaminated water and solids are disclosed. In some embodiments, the systems include the following: a plurality of automated robotic oil recovery units; a plurality of deployable oil collection membranes positioned within each of the units, each of the membranes including an upper half including a material impermeable to both water and crude oil and a lower half including a semi-permeable hydrophilic membrane that is permeable to water but impermeable to crude oil; and a high pressure carbon dioxide oil solids separation unit for separating oil from oil-contaminated solids thereby producing substantially oil-free solids and an oil and carbon dioxide mixture; a solids separation unit for the separating substantially oil-free solids from the oil and carbon dioxide mixture via gravity separation; and an oil separation unit for separating oil from the oil and carbon dioxide mixture using a pressure swing.

Description

CROSS REFERENCE TO RELATED APPLICATION(S)

This application claims the benefit of U.S. Provisional Application No. 61/521,300, filed Aug. 8, 2011, which is incorporated by reference as if disclosed herein in its entirety.

BACKGROUND

While the number of major oil tanker spills has decreased significantly in the last decade due to safer shipping lanes and better engineered double hulls, crude oil spills in the marine environment continue to be a major environmental, political, and economic issue. Other large-scale oil spills such as the BP oil accident in 2010 can also be considered under the same category. Traditional methods of oil spill cleanup include in situ burning, containment using booms and skimmers, and dilution with chemical dispersants. Not only are these methods inefficient in that they require significant amounts of time and manpower, they themselves often lead to significant environmental damage either through the release of significant greenhouse gases or toxic chemicals.

Current oil spill cleanup technologies have the following shortcomings: 1. Cleanup cannot keep up with the rate of the oil spill leading to large area of contamination; 2. Require large amount of time and manpower; 3. Cannot recover most of the collected oil (absorbents are landfilled—another environmental problem).

However, even in recent years where little crude oil was spilled, such as in 2004, over 25,000 tonnes of crude oil were spilled and damaged the marine environment. The majority of crude oil spilled in a year typically derives from a major crude oil spill in which more than 1000 barrels are spilt.

According to the National Oceanic and Atmospheric Administration's (NOAA) Emergency Crude Oil Spill Response website, marine oil spills can involve many types of fuels, ranging from refined liquid petroleum from ships and recreational vessels to crude oil from tankers and offshore rigs. Of these fuels, crude oil poses the largest threat to the environment, as crude oil poisons and damages the flora and fauna of the marine ecosystem. It can become embedded in the sand and mud of shorelines, lasting for years after the spill occurred.

Apart from the long lasting environmental impacts, crude oil spills must be dealt with swiftly and effectively because crude oil spills result in political tension between environmental groups, the government, and crude oil companies. Crude oil spills also introduce major economic losses and public image damage to both crude oil companies and coastal communities.

NOAA's website gives descriptions of the current off shore crude oil spill cleanup technologies designed to meet the following primary objectives: (a) Prevent the spill from moving onto shore; (b) Reduce the impact of crude oil on marine life; and (c) Speed the degradation of any unrecovered crude oil.

For open-water crude oil spills, if weather permits, booms are used to temporarily contain crude oil between the surface and up to a few feet below the surface with special nets that do not allow crude oil to pass through. However, wave action renders booms highly ineffective.

Skimmers outfitted with pumps on board emergency boats are often used to clean up oil contained in booms. These skimmers usually employ suction pumps to intake surface crude oil. The crude oil is then stored in underwater tanks. Skimmers are only effective in calm waters, though, and are limited by the power-draining pumps and heavy tanks. An alternative to the pump is a skimmer that contains an oil-absorbing cloth. The cloth is dragged along the surface and oil is squeezed out of it when the cloth is saturated. Therefore, oil can be recovered. Nonetheless, the process of squeezing out the oil is very energy intensive. While the cloths can be reused, their capacity to collect oil is greatly reduced with each use. Furthermore, the used, oily cloth must be land filled after use, presenting an environmental concern.

Controlled burns of the oil slick within booms are also very common. They are relatively effective, however this process releases massive amounts of carbon dioxide and none of the crude oil can be recovered.

Chemical dispersants sprayed from aircraft or emergency ships onto the area of containment is a method used to break up crude oil surface slicks. The breakup of crude oil helps microbes to digest the crude oil faster and prevents crude oil slicks from poisoning and coating marine wildlife which inhabit or breathe at the ocean surface. The chemical properties and environmental effects of dispersants however, are not fully understood, and may be as detrimental to the marine environment as the crude oil itself. Furthermore, dispersants often exacerbate the spreading of crude oil over a large area and depth, especially when stronger currents are present. None of the crude oil can be recovered.

All of these cleanup methods are problematic in that they are highly labor intensive since they require manual deployment/coordination and may require specially trained technicians. In addition, their implementation and transport to the spill site often takes a significant amount of time since they arrive via emergency ships, which may not be near the spill. This time lag allows the oil to spread great distances, increasing the likelihood of shoreline oiling and contact with the marine environment. The spreading also makes cleanup more difficult since a greater area must be treated.

SUMMARY

Embodiments of the disclosed subject matter include oil spill cleanup systems that include self-powered automated oil recovery robotic units and a soil cleaning system that uses carbon dioxide as a leaching media.

In systems according to the disclosed subject matter, the self-powered automated oil recovery robotic units are kept on board a tanker ship, similar to life boats. They are designed with solar panels so that they can store solar energy for the emergency situations. During non-emergency times, the generated excess energy is used for the operation of the tanker ships. If there is an oil spill, the self-powered automated oil recovery robotic units are deployed to collect and capture oil using special membranes until they can be recovered. Therefore, the crew can focus on the repair of the tanker ship or other emergency related activities. The collected oil is then pumped into a new tanker once it arrives to the spill site. Components of the robotic units, i.e., the membranes, are easily cleaned and recycled.

Oil spill cleaning technology according to the disclosed subject matter is designed to clean the contaminated soil using high pressure carbon dioxide. Since liquid or supercritical carbon dioxide is miscible with oil, carbon dioxide will separate oil from the particle surface. Once oil is leached out, the soil/sand can be separated via gravity separation. The separation of oil and carbon dioxide is easy since carbon dioxide can be vaporized by lowering the pressure. In fact, a smaller pressure swing can also be used to keep carbon dioxide in liquid phase and recycle it through the cleaning system. With both the robotic units and the cleaning system, oil can be recovered in a useable form instead of being landfilled.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings show embodiments of the disclosed subject matter for the purpose of illustrating the invention. However, it should be understood that the present application is not limited to the precise arrangements and instrumentalities shown in the drawings, wherein:

FIG. 1 is a schematic diagram of systems according to some embodiments of the disclosed subject matter;

FIG. 2 is a side section view of an automated robotic oil recovery units according to some embodiments of the disclosed subject matter;

FIG. 3 is a back section view of an automated robotic oil recovery units according to some embodiments of the disclosed subject matter; and

FIG. 4 is a side section view of an automated robotic oil recovery unit according to some embodiments of the disclosed subject matter.

DETAILED DESCRIPTION

Referring now to FIGS. 1-4, aspects of the disclosed subject matter include a system 100 for cleaning oil spills, which includes a plurality of automated robotic oil recovery units 102 and a solids cleaning module 104.

Referring now to FIGS. 1 and 2, each of automated robotic oil recovery units 102 includes deployable membranes 106 for collecting oil 108 and each of the units is configured for deployment from a ship 110 for automated capture and recovery of oil from oil-contaminated water 112 and solids 114. In some embodiments, system 100 will include units 102 of varying sizes.

Referring now to FIGS. 3 and 4, in some embodiments, deployable membranes 106 include an upper half 116 including a material 118 impermeable to both water 120 and crude oil 108, e.g., HDPE or similar, and a lower half 124 including a semi-permeable hydrophilic membrane 126 that is permeable to water 120 but impermeable to crude oil 108, e.g., as disclosed in published U.S. Patent Application US2011/0303620, by Dr. Di Gao, which is incorporated by reference as if disclosed herein in its entirety.

Referring now to FIGS. 1-4, each of units 102 include an outer shell 128 having a shock-absorbing lining 130 for protecting inner components of the units from forces generated by impact on water when deploying the units from ship 110 and from corrosion from seawater 132. Outer shell 128 includes a plurality of channels 134 formed on an inner surface 136 of the outer shell. Channels 134 are configured to allow oil-contaminated water 112 to flow through units 102 and keep membranes 106 open when stored in outer shell 128. Each of units 102 includes a membrane deployment track 138 for deploying membranes 106 one by one and holding one end of a membrane in place while collecting oil 108.

Referring now to FIG. 4, each of units 102 includes inflatable membrane supports 140 for keeping membranes 106 floating on the surfaces 142 of water 132 and visible to collection vessels. Each of units 102 also include deployable inflatable body supports 144 and air tanks 146 for inflating the inflatable body supports and inflatable membrane supports 140.

Referring now to FIGS. 2-4, each of units 102 include a power unit 148 including a motor 150, one or more batteries 152, a propeller unit 154, and a gas tank 156. Power unit 148 is contained in a substantially waterproof storage compartment 158 formed within shell 128. Each of units 102 also includes solar panels 160 for charging batteries 152. Each of units 102 includes a protective mesh 162 for preventing seaweed and other debris from entering the units and damaging propeller unit 154.

Referring now to FIG. 1, in some embodiments, system 100 includes a plurality of booms 164 connected to automated robotic oil recovery units 102 thereby allowing the units to form a ring of booms for containing an oil spill. In some embodiments, a hollow boom, which includes pumps embedded along its circumference, can be used.

Referring now to FIG. 2, each of units 102 includes a GPS control unit 166 for coordinating positions of each of the plurality of automated robotic oil recovery units of the system around an oil spill and identifying its position when it needs to be recovered. In some embodiments, GPS control unit 166 includes an antenna 168.

Referring again to FIG. 1, although not illustrated in detail, solids cleaning module 104, which is used for separating and recovering oil from oil-contaminated solids that are captured by automated robotic oil recovery units 102, include the following: a high pressure carbon dioxide oil solids separation unit for separating oil from oil-contaminated solids thereby producing substantially oil-free solids and an oil and carbon dioxide mixture; a solids separation unit for the separating substantially oil-free solids from the oil and carbon dioxide mixture via gravity separation; and an oil separation unit for separating oil from the oil and carbon dioxide mixture using a pressure swing.

Systems according to the disclosed subject matter offer advantages and benefits over known technology. A large scale oil spill causes great economic damage to companies. Thus, there is a significant commercial need for a technology that minimizes environmental issues related to potential spills. Thus, like a having an airbag in your car, the installation of oil spill cleanup devices according to the disclosed subject matter will lower the insurance for the tankers and provide better environmental measures for the companies.

Self-powered on-board robotic system according to the disclosed subject matter offer the following advantages over known systems: 1. Cleanup can keep up with the rate of the oil spill leading to limited area of contamination; 2. Require minimum amount of time and manpower; and 3. Can recover most of the collected oil (no landfill needed).

High pressure carbon dioxide soil/sand cleaning systems according to the disclosed subject matter offer the following advantages over known systems: 1. Can recover most of the collected oil (no landfill needed); 2. Mobile unit (can be installed at the back of a truck)—can clean up spills at various locations; and 3. Save environment. Systems using carbon dioxide as a leaching medium are also used for any other environmental contaminations associated with soil, sand, or particles.

Although the disclosed subject matter has been described and illustrated with respect to embodiments thereof, it should be understood by those skilled in the art that features of the disclosed embodiments can be combined, rearranged, etc., to produce additional embodiments within the scope of the invention, and that various other changes, omissions, and additions may be made therein and thereto, without parting from the spirit and scope of the present invention.

Claims

1. A system for cleaning oil spills, comprising:

a plurality of automated robotic oil recovery units, each of said units including deployable membranes for collecting oil and each of said units configured for deployment from a ship and for automated capture and recovery of oil from oil-contaminated water and solids; and

a solids cleaning module for separating and recovering oil from oil-contaminated solids.

2. The system according to claim 1, wherein each of said deployable membranes comprise:

an upper half including a material impermeable to both water and crude oil; and

a lower half including a semi-permeable hydrophilic membrane that is permeable to water but impermeable to crude oil.

3. The system according to claim 1, wherein each of said plurality of automated robotic oil recovery units comprise:

an outer shell including a shock-absorbing lining for protecting inner components of said system from forces generated by impact on water when deploying said system from a ship and from corrosion from seawater;

a plurality of channels formed on an inner surface of said outer shell, said channels configured to allow oily water to flow through said system and keep said membranes open when stored in said shell;

4. The system according to claim 1, further comprising:

a plurality of inflatable membrane supports for keeping said membranes floating on the surfaces of the water and visible to collection vessels;

a plurality of deployable inflatable body supports; and

air tanks for inflating said inflatable body supports and said inflatable membrane supports.

5. The system according to claim 3, further comprising:

a power unit including a motor, a battery, a propeller unit, and a gas tank; and

a substantially waterproof storage compartment formed within said shell that includes said power unit.

6. The system according to claim 5, further comprising solar panels for charging said batteries.

7. The system according to claim 1, further comprising a membrane deployment track for deploying said membranes one by one and holding one end of a membrane in place while collecting oil.

8. The system according to claim 5, further comprising a protective mesh for preventing seaweed and other debris from entering said system and damaging said propeller unit.

9. The system according to claim 1, further comprising a GPS control unit for coordinating positions of each of said plurality of automated robotic oil recovery units of said system around an oil spill and identifying its position when it needs to be recovered.

10. The system according to claim 1, said solids cleaning module further comprising:

a high pressure carbon dioxide oil solids separation unit for separating oil from oil-contaminated solids thereby producing substantially oil-free solids and an oil and carbon dioxide mixture;

a solids separation unit for said separating substantially oil-free solids from said oil and carbon dioxide mixture via gravity separation; and

an oil separation unit for separating oil from said oil and carbon dioxide mixture using a pressure swing.

11. The system according to claim 1, further comprising:

a plurality of booms configured to connect to said plurality of automated robotic oil recovery units thereby allowing said units to form a ring of booms for containing an oil spill.

12. A system for automated capture and recovery of oil from oil-contaminated water and solids, comprising:

a plurality of automated robotic oil recovery units;

a plurality of deployable oil collection membranes positioned within each of said units, each of said membranes including an upper half including a material impermeable to both water and crude oil and a lower half including a semi-permeable hydrophilic membrane that is permeable to water but impermeable to crude oil; and

a solids cleaning module for separating and recovering oil from oil-contaminated solids.

13. The system according to claim 12, further comprising:

a plurality of inflatable membrane supports for keeping said membranes floating on the surfaces of the water and visible to collection vessels.

14. The system according to claim 12, further comprising a GPS control unit for coordinating positions of each of said plurality of automated robotic oil recovery units of said system around an oil spill and identifying its position when it needs to be recovered.

15. The system according to claim 12, said solids cleaning module further comprising:

a high pressure carbon dioxide oil solids separation unit for separating oil from oil-contaminated solids thereby producing substantially oil-free solids and an oil and carbon dioxide mixture;

a solids separation unit for said separating substantially oil-free solids from said oil and carbon dioxide mixture via gravity separation; and

an oil separation unit for separating oil from said oil and carbon dioxide mixture using a pressure swing.

16. The system according to claim 12, further comprising:

a plurality of booms configured to connect to said plurality of automated robotic oil recovery units thereby allowing said units to form a ring of booms for containing an oil spill.

17. A system for automated capture and recovery of oil from oil-contaminated water and solids, comprising:

a plurality of automated robotic oil recovery units;

a plurality of deployable oil collection membranes positioned within each of said units, each of said membranes including an upper half including a material impermeable to both water and crude oil and a lower half including a semi-permeable hydrophilic membrane that is permeable to water but impermeable to crude oil; and

a high pressure carbon dioxide oil solids separation unit for separating oil from oil-contaminated solids thereby producing substantially oil-free solids and an oil and carbon dioxide mixture;

a solids separation unit for said separating substantially oil-free solids from said oil and carbon dioxide mixture via gravity separation; and

an oil separation unit for separating oil from said oil and carbon dioxide mixture using a pressure swing.

18. The system according to claim 17, further comprising:

a plurality of inflatable membrane supports for keeping said membranes floating on the surfaces of the water and visible to collection vessels.

19. The system according to claim 17, further comprising a GPS control unit for coordinating positions of each of said plurality of automated robotic oil recovery units of said system around an oil spill and identifying its position when it needs to be recovered.

20. The system according to claim 17, further comprising:

a plurality of booms configured to connect to said plurality of automated robotic oil recovery units thereby allowing said units to form a ring of booms for containing an oil spill.