Patent Grant
8425668
1. The Field of the Invention
The present invention relates to wastewater treatment systems and methods that utilize a water evaporator for separating wastewater from salts, minerals, and/or oil and/or gas.
2. The Relevant Technology
As natural gas is extracted from a ground well, a significant quantity of water accompanies the natural gas. This water is typically separated from the natural gas at a location proximate to the well head and then stored in an adjacent tank. Because of contaminants within the water, the water is typically trucked to a licensed disposal facility where it is deposited in a lined pond for evaporation. This same operation also typically occurs in the production of oil wells. That is, a significant quantity of water will often accompany extracted oil. The water and oil are deposited in a settling tank where the water and oil are separated. The water is then typically trucked to a licensed disposal facility where it is deposited in a lined pond for evaporation. Evaporation of the collected water is typically enhanced by sprinkler systems that spray the water into the air over the pond.
Although the above process is functional, there are significant costs in having to repeatedly ship the water to the disposal facility. There are also significant costs charged by the disposal facility to accept the water. Furthermore, trying to dispose of water through an evaporation pond can be problematic. For example, under windy conditions the sprinkler system cannot be operated due to the risk of non-evaporated fluid being carried by the wind onto the surrounding area. Furthermore, during colder or high humidity conditions, evaporation may fall below a desired evaporation rate.
Accordingly, what is needed are systems that eliminate or minimize the above problems or shortcomings.
Various embodiments of the present invention will now be discussed with reference to the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope.
The present invention relates to wastewater treatment systems and methods for treating wastewater streams. The wastewater treatment systems include a water evaporator that reduces the volume of the wastewater. The wastewater treatment systems can also include additional components or systems to perform one or more of the following features: separating components of the wastewater stream, collecting the evaporated water, generating electrical or mechanical power, and/or utilizing low-value hydrocarbons in a cost effective and environmentally friendly manner.
The water evaporation systems include a housing assembly providing a fluid reservoir and bounding an air flow path. A misting system is configured to spray wastewater from the fluid reservoir into the air flow path. A portion of the wastewater is evaporated, thereby concentrating salts and/or minerals in the fluid reservoir. The concentrated waste can be efficiently handled and/or disposed of.
The wastewater treatment systems include one or more sources of heat, which is delivered through the air flow path of the housing assembly to enhance evaporation. In various embodiments of the invention, the wastewater treatment system can include generators, motors, thermal oxidizers, gas furnaces, and the like to generate heat and/or create an airstream that can evaporate substantial quantities of water. The use of these components can produce a synergistic benefit that enhances the environmentally favorable treatment and disposal of a wastewater stream.
In some embodiments of the invention, the evaporation system can include one or more demisters near the air outlet of the evaporation system to remove suspended water droplets. The demisters remove suspended water without preventing expulsion of the evaporated water, thereby reducing amount of salt, metals, and other dissolved materials that escape through the airstream.
Some embodiments of the invention may also include a pretreatment system for separating hydrocarbons and wastewater to further facilitate efficient evaporation of the wastewater in the water evaporator.
In yet other embodiments, the water treatment systems can include condensers downstream from the evaporation system to condense the evaporated water from the air stream to produce desalinated and/or potable water.
Although the water treatment systems can be used in a variety of different situations where it is desirable to evaporate a large quantity of water, the present invention will often be used in association with the oil and gas industry. Some embodiments of the invention may be particularly advantageous when carried out at or near the oil and/or gas well.
Depicted in
During production of well source 212, fluids such as water and oil are passed out of well source 212 and are delivered, either directly or indirectly, to storage and separation system 214. Storage and separation system 214 can be an underground storage tank and/or above ground storage tanks. Storage and separation system 214 can include a single tank or two or more tanks in series and/or in parallel. In one embodiment, storage and separation system 214 can include a separation apparatus that separates crude hydrocarbons into a wastewater stream and hydrocarbon products. Within storage and separation system 214, the water and oil separate with the oil rising to the top and the water settling to the bottom. A pipe 218 is then used to convey the wastewater from storage and separation system 214 to water evaporation system 210. The water can be conveyed either under the force of gravity or by the use of a pump 219. As discussed below in greater detail, water evaporation system 210 is then used to evaporate the water and disperse it into the surrounding environment. If desired, a flow meter 221 can be mounted on pipe 218 so as to provide an exact measurement of how much fluid has been evaporated through water evaporation system 210.
It is appreciated that the water can be delivered to water evaporation system 210 using a variety of different methods. For example, in contrast to storage and separation system 214 being fluid coupled with a well head, the fluid can be delivered to storage and separation system 214 by truck, rail, or other transport mechanism. Furthermore, in contrast to water evaporation system 210 being coupled with storage and separation system 214, the water can be delivered to water evaporation system 210 directly from a settling pond or other type of container system Likewise, the water can be delivered to water evaporation system 210 directly from a truck, rail car, or other type of vehicle.
The wastewater is delivered to evaporation system 210 to have its mineral content concentrated. Concentrated waste 126 can then be more economically disposed of. In one embodiment, wastewater stream 106 and/or 120 is delivered to evaporation system 210 with a total dissolved solids content in a range from about 1% to about 15%, more typically in a range from about 2%-10%. The concentrated waste 126 has a higher mineral concentration. In one embodiment, the total dissolved solids of concentrated waste 126 may be in a range from about 10% to about 70%, more typically in a range from about 15% to about 50%.
Turning to
In one embodiment, housing 220 comprises a standard metal shipping container having standard dimensions that has been modified for the intended use of the present invention. For example, standard metal shipping containers intended for intercontinental use typically have external standard dimensions of length 20 feet (6.10 m), 30 feet (9.14 m), or 40 feet (12.20 m); width of 8 feet (2.44 m); and height of 8.5 feet (2.59 m) or 9.5 feet (2.90 m). These dimensions are only approximations and can vary within a few inches, such as within six inches (0.15 m). For example, the 30 feet containers are typically closer to 29.9375 feet (9.125 m) in length. Other standard and non-standard dimensions can also be used. In the illustrated example of the present invention, housing 220 has a length of 40 feet (12.20 m), a width of 8 feet (2.44 m), and height between 8.5 feet (2.59 m) to 9.5 feet (2.90 m) each within a tolerance of six inches (0.15 m).
By forming housing 220 out of standard shipping containers, housings 220 can be stacked, if desired, and easily transported by rail, ship, truck or the like using conventional techniques. In an alternative embodiment, housing 220 can be custom designed having other dimensions and configurations and can be made from other materials such as wood, plastic, fiberglass, composite, and the like.
Depicted in
As depicted in
As depicted in
As depicted in
With reference to
An inlet opening 352 extends through roof 322 so as to communicate with evaporation chamber 566 at first end 325 while an outlet opening 354 extends through roof 322 so as to communicate with evaporation chamber 566 at second end 327. As will be discussed below in greater detail, housing assembly 211 can include a tubular stack 356 mounted on roof 322 so as to be disposed over outlet opening 354. Stack 356 has an interior surface 358 bounding a passage 360 extending between an upper end 362 and an opposing lower end 364. Upper end 362 provide an outlet opening for housing assembly 211. Stack 356 typically has a height extending between the opposing ends in a range between about 1 meter to about 30 meters with about 2 meters to about 5 meters being more common. Other lengths can also be used. In one embodiment, stack 356 can be hingedly mounted to roof 322 so that stack 356 can be selectively folded over to rest on top of roof 322 during transport of housing 210 and then folded upward and secured in position for final use.
Returning to
As previously discussed with regard to
In one embodiment of the present invention, means are provided for filtering fluid 576. By way of example and not by limitation, a weir 586, as shown in
Air flow path 574 comprises the area within the evaporation chamber 566 that is vertically above fluid reservoir 572. Accordingly, from one perspective, the boundary between air flow path 574 and reservoir 572 can be top surface 578 of pooled fluid 576. That is, the area above top surface 578 is air flow path 574 while the area below top surface 578 is fluid reservoir 572. As top surface 578 raises within evaporation chamber 566, the volume of fluid reservoir 572 increases while the volume of air flow path 574 decreases.
With continued reference to
In the embodiment depicted baffle 580 has a substantially rectangular base portion 582 extending between opposing sidewalls 228 and 330 and a substantially triangular portion 84 that extends from base portion 782 down to an apex 786 that is centrally positioned between opposing sidewalls 228 and 330. It is appreciated that baffle 580 can come in a variety of different sizes, shapes, and configurations. Examples include, but are not limited to baffles having a substantially triangular, semicircular or semielliptical configuration, or a substantially square or rectangular configuration. Baffle 580 can be positioned above top surface 578 of pooled fluid 576. Alternatively, baffle 580 or any of the other baffles can be formed from a porous material or have a plurality of openings 581 that extend therethrough so that the air and moisture can pass therethrough. In this embodiment, the baffle can extend down into pooled fluid 576. It is also noted that baffle 80 need not be a flat plate but can be contoured and/or can have a uniform or varied thickness.
In one embodiment of the present invention, means are provided for regulating the level of fluid 576 within fluid reservoir 572. By way of example and not by limitation, a sensor 630 (
Returning to
Disposed within storage chamber 568 is a pump 501. As shown in
As will be discussed below in greater detail, at least a portion of fluid 576 sprayed within air flow path 574 evaporates and is removed out of air flow path 574. By having fluid 576 sprayed upward and then fall back down, the duration that the sprayed fluid 576 is suspended within air flow path 574 is maximized so as to maximize evaporation of fluid 576 within air flow path 574. In an alternative embodiment, fluid 576 can simply be sprayed down from roof 322.
It is appreciated that the means for spraying fluid 576 pooled within fluid reservoir 572 can have a variety of different configurations. By way of example and not by limitation, it is appreciated that piping 588 can be mounted on or below floor 324 and/or on or above roof 322. Elongated risers can then be used to position spray nozzles 596 at the desired position within air flow path 574. In contrast to having two pipe sections 590 and 592, it is appreciated that a single pipe section can be used that is either centrally positioned between or is positioned along one of the sidewalls. Alternatively, three or more spaced apart pipe sections can be used. It is likewise appreciated that the, type, size, configuration, number, orientation, and position of spray nozzles 596 can be dramatically varied. The general concept is to spray fluid 576 into air flow path 574 at a flow rate and concentration that will maximize the evaporation of fluid 576 within air flow path 574.
In one embodiment of the present invention, means are provided for drawing air from the surrounding environment into air flow path 574 through inlet opening 352 and for drawing the air out of air flow path 574 through outlet opening 354. By way of example and not by limitation, depicted in
It is appreciated that a variety of different types of fans can be used within stack 356 or outlet opening 354 for drawing the air out of air flow path 574. In alternative embodiments, it is appreciated that a fan can be positioned at or adjacent to inlet opening 352 for drawing air into air flow path 574 or pushing air into airflow path 354. Likewise, in contrast to forming inlet opening 352 on roof 322, inlet opening 352 can also be formed on partition wall 565 and receive air through slot 350 or the alternatives thereto as previously discussed. Inlet opening 352 can also be formed on sidewall 228 or 330. Similarly, outlet opening 354 can be formed on sidewall 228 or 330 or end wall 334. In these embodiments, stack 356 would have a 90° elbow to connect with outlet opening 354.
During operation, a continuous flow of fresh air is drawn in from the environment and passed between inlet opening 352 and outlet opening 354 along air flow path 574. Spraying fluid 576 within air flow path 574 between inlet opening 352 and baffle 380 causes the air flow in that region to be highly turbulent. The combination of spraying fluid 576 in a fresh air stream that is highly turbulent and that is heated within air flow path 574 due to the ambient temperature and radiant energy striking housing 220 serves to optimize the evaporation of sprayed fluid 576 within air flow path 574.
Baffle 580 and stack 356 help to facilitate removal of non-evaporated water droplets from the air flow before the air flow exits stack 356 and travels back into the surrounding environment. This is to help ensure that water droplets do not simply pass out through stack 356 and then deposit on the ground surrounding housing 220. With regard to baffle 580, spray nozzles 596 typically do not extend past baffle 580 so that the air flow between baffle 580 and outlet opening 354 is less turbulent than between inlet opening 352 and baffle 580. Baffle 580 thus in part functions as a shield to help minimize the amount of sprayed fluid that is passed beyond baffle 580 and thus decrease air turbulence beyond baffle 580. Baffle 580 also partially constricts that area of air flow path 574 at the location of baffle 580. By constricting air flow path 574, the air flow becomes more laminar as it travels around baffle 580. Likewise, the air flow increases in speed as it travels through the area constricted by baffle 580 but then slows down as it expands into the larger space on the opposing side of baffle 580. As a result of producing a slower, less turbulent air flow, fluid droplets that are carried by the air flow but that have not yet evaporated, drop out of the air flow and back into fluid reservoir 572. Stack 556 provides added retention time for the air flow to help ensure that substantially all of the non-evaporated fluid droplets fall out of the air flow before the air flow exits stack 556. Furthermore, by being vertically oriented, the fluid droplets falling out of the air flow fall through the upcoming air flow so as to combine with and collect other fluid droplets.
On occasion, such as during the colder months of the year or during a short term cold period, the ambient temperature and radiant energy produced by the sun may not be sufficient to facilitate evaporation of fluid 576 at a desired rate. Accordingly, in one embodiment of the present invention, means are provided for blowing heated air into air flow path 574. By way of example and not by limitation, a furnace 514 is disposed within storage chamber 568. Furnace 514 comprises a heating element and a fan. A tubular vent 926 extends from furnace 514 through partition wall 565 into air flow path 572. Furnace 514 can be designed to operate on electricity, gasoline, natural gas and/or propane or other fuels. For example, natural gas from well head 112 can be used to operate furnace 514.
Turning to
Returning to
It is appreciated that the above discussion is only one embodiment of how water evaporation system 100 can be configured and that the various components can be moved around. For example, by making plumbing modification, it is appreciated that baffle 580 and stack 556 can be positioned toward partition wall 565 while inlet opening 352 and spray nozzles 596 are positioned toward second end wall 334.
The present invention also envisions a variety of other embodiments of wastewater treatment systems. For example, depicted in
Wastewater treatment system 100A includes well source 212. Hydrocarbons extracted from well source 212 can be delivered via pipe 216 to be stored in storage and separation system 214. Hydrocarbons are separated in storage and separation system 214 to produce a wastewater stream 106 and hydrocarbon products 108. Storage and separation system 214 may also provide for separating volatile organic compounds (VOCs) 110 from wastewater stream 106 and hydrocarbon products 108. As explained in more detail below, the VOCs can be used to generate heat in a thermal oxidizer 114.
In one embodiment wastewater stream 106 may optionally be delivered to a pretreatment system 116 for additional separation. Pretreatment system 116 is described more fully below with respect to
Wastewater treatment system 100A further includes one or more sources of heat for increasing the rate of evaporation of the wastewater in water evaporation system 210A. In one embodiment, the source of heat can be a thermal oxidizer 114 configured to oxidize volatile organics 110 from storage and separation system 214 and/or pretreatment system 116 and/or gas from well 212. In an alternative embodiment, methane and/or another type of hydrocarbon from well source 212 can be delivered through a pipe 128 to a furnace 514A and/or a generator 924A, where the fuel can be burned to produce heat, air flow, mechanical power, and/or electricity. The heat from furnace 514A and/or generator 924A can be delivered to water evaporation system 210A to facilitate the evaporation of wastewater. Generator 924A may also be connected to a power grid 134 and used to generate electrical power for grid 134.
In one embodiment, a significant portion of the heat generated for water evaporation system 210A can be a waste heat. The term “waste heat” includes heat derived from electrical generation and/or the burning or oxidizing of hydrocarbons that are of little value due to their impurity and/or cost of handling. For example, waste heat includes heat derived from the exhaust of an electrical generator and/or the thermal oxidation of volatile organic compounds, but does not include heat generated from burning pipeline quality gas in a furnace. In one embodiment, at least about 20% to about 100% of the total heat generated and input into water evaporation system 210 is a waste heat, more specifically about 30% to about 95%, and even more specifically 50% to about 90%. In one embodiment, at least about 30%-100% of the heat is produced from a turbine (i.e., non-reciprocating) engine, more specifically about 50% to about 70%. In one embodiment, about 10%-70%, of the heat is produced from a reciprocating engine, more specifically about 30% to about 50%. In one embodiment about 20% to about 100% is generated from a non-engine process such as a furnace or thermal oxidizer, more specifically about 30% to about 80%.
Any type of thermal oxidizer 114 may be used in system 100A so long as the thermal oxidizer is compatible with the hydrocarbon source being oxidized. Examples of suitable thermal oxidizers include regenerative thermal oxidizers, regenerative catalytic oxidizer thermal recuperative oxidizer, catalytic oxidizer, and/or direct fired thermal oxidizer (i.e. afterburner). The heat from the thermal oxidizer can be piped directly into water evaporation system 210A or can be used to heat wastewater stream 120 in a heat exchanger. Those skilled in the art are familiar with selecting thermal oxidizers that can efficiently create a hot air stream and/or heat a fluid in a heat exchanger. The use of thermal oxidizer 114 not only provide heat for the rapid evaporation of wastewater but it also efficiently and safely disposes of unwanted VOCs.
System 100A may also include furnace 514A as described above. Furnace 514A can be operated using natural gas or another hydrocarbon source. The hydrocarbon source can be purified, partially purified, unpurified, refined, and/or unrefined. Furnace 514A is typically configured and/or positioned within or adjacent water evaporation system 210 to maximize heat transfer to the air flow in evaporation system 210. For example, in one embodiment furnace 514A can have the same size and relative placement as furnace 514 as previously discussed with regard to
Generator 924A can comprise any type of electrical generator. For example, generator 924A may be an internal combustion engine or a micro turbine. Generator 924A can be configured to generate electrical power for transferring to power grid 134. Thus, generator 924A can be used to convert the natural gas from well source 212 to electricity which can then be transferred onto power grid 134. This eliminates the need for creating a gas line that transfers the gas to an established collection line. In addition to or in the alternative, generator 924A can be configured to generate the electricity necessary to power all the electrical components and mechanical components of water treatment system 100A. For example, generator 924A can drive a compressor, pump, a control unit and various valves. Thus, generator 924A can comprise generator 924 as previously discussed with regard to
Wastewater treatment system 100A may also include a control unit 136 housing electrical components configured to control any of the components of system 100A. In one embodiment, control unit 136 includes hardware and/or software for operating one or more of fans, pumps, valves, motors, turbines, sensors, and the like to maintain and/or change the state of system 100A. In one embodiment, control unit 136 includes CPU 920 and software that monitors the state of the system through sensors 922 (
Generator 924A can be sized and configured to produce a desired amount of heat for evaporation system 210A and/or to generate a desired amount of electrical power. As discussed above, in one embodiment, the electrical generator can be sized and configured to provide sufficient power for running the electrical systems of system 100A, including the control unit 136. This arrangement can be advantageous where the well source 212 is not near a power transmission line. In this embodiment, additional heat sources (e.g., thermal oxidizer, gas furnace, etc.) may be needed to provide sufficient heat for evaporation system 210A.
Alternatively, or in addition, one or more generators 924A can be configured to generate excess power for a grid, in which case, the power generation can greatly exceed the power needs of system 100A and the heat value of the exhaust can provide a substantial percentage and/or all of the heat in water evaporation system 210A. In one embodiment, one or more generators 924A used in system 100 have a total power output in a range from about 250 kW to about 20 MW, more specifically in a range from about 1 MW to about 15 MW, and even more specifically in a range from about 2 MW to about 10 MW. In an alternative embodiment, one or more generators can be sized to produce an exhaust coupled to the evaporation system 210A and providing at least about 30% to about 100% of the total heat input to evaporation system 210A, more specifically about 50% to about 70%.
Generator 924A may be gas powered or liquid fuel powered. However, gas powered is often advantageous at remote wells where petroleum distillates are difficult to obtain. Where a gas generator is used, the gas may be purified, partially purified, or unpurified (e.g., pipeline quality gas or not). Pipeline quality gas can be provided by conditioning the gas from well source using techniques known in the art. In a preferred embodiment, the gas used for generator 924A is only partially purified or unpurified.
Advantageously the systems and methods of the invention can employ a contaminated gas source (i.e., gas that is not pipeline quality). This can be made possible by delivering the exhaust from combustion into evaporation system 210A. Contaminates contained in the exhaust gas may be scrubbed by the moisture in evaporation system 210A and disposed of with concentrated waste 126 as described more fully below with respect to the evaporator systems. In one embodiment, the gas stream used for generator 924A can even include contaminants such as hydrogen sulfide where the contaminant has a concentration that prevents the use of the gas in residential gas pipelines and/or prevents its use in a combustion engine where the exhaust from combustion would fail environmental regulations. Gas that is contaminated with contaminates such as hydrogen sulfide and/or other impurities is often very inexpensive compared to pipeline quality gas due to the cost of gas conditioning to achieve the desired purity. In one embodiment, the gas employed in the generator 924A is not pipeline quality gas. For example, in one embodiment, the gas employed in generator 924A may not fulfill the requirements of 40 CFR §72.2 of the 1999 revisions to 40 CFR Parts 72 and 75. In one embodiment, the gas employed in generator 924A may include less than 70% methane by volume and/or include hydrogen sulfide content greater than 0.3 grams/100 scf or greater than 1.0 grams/100 scf.
Wastewater treatment system 100A may advantageously be constructed and or operated at a remote location. Because well source 212 is typically a natural oil or gas reserve, the location of well source 212 is dictated by geography rather than convenience. In many cases, well source 212 may be a substantial distance from a gas pipeline or a gas conditioning facility. The use of waste heat from the combustion of gas at a remote location can provide a synergistic benefit to reducing the cost of disposing of wastewater produced from a well source. The synergy from power generation and wastewater treatment near the well source arises from the shipping costs associated with transporting the wastewater and the transportation costs associated with transporting a gas in a pipeline to an alternative location. By producing the power near the well head, the costs of cleaning and/or transporting the gas can be avoided with impunity and/or the waste heat from the generation can be economically put to use in treating the wastewater from the well source. In addition, since the wastewater evaporation system 210 is configured to concentrate impurities, the exhaust from generator 924 (or thermal oxidizer 114) can be easily “scrubbed” as it is used to heat the wastewater. Even where the exhaust has relatively high concentrations of impurities, the exhaust is “scrubbed” of its impurities as it travels through evaporating system 210. Thus the combination of power generation and wastewater treatment synergistically benefits each other with little or no additional expense. While using impure gas to operate generator 924A may be advantageous in some embodiments, the us of impure gas is not required. In some cases using higher quality gas (e.g., pipeline quality gas) may be advantageous (e.g., to reduce wear and tear on generator 924A).
The use of generator 924A may be particularly advantageous for wells that are sufficiently far from a gas pipeline that gas transportation costs are an issue. In this embodiment, power can be placed on a grid without having to set up a long distance delivery system for gas. In this embodiment, the use of pipeline quality gas may be economical since the power generation also produces a waste heat that can be used in evaporation system 210A.
Evaporator housing 220 has a substantially flat roof 222 and an opposing floor 224 that each extend between a first end and an opposing second end. An encircling sidewall includes a first sidewall 228 and an opposing second sidewall 330 that each extend between first end 1032 and an opposing second end 1034. Housing 220 bounds an evaporation chamber 588. First end 1032 may be open to ambient air or a source of forced air and may include doors 348 and 349. An opening 1004 can provide a doorway that allows entry into mechanical room 1038 near end 1032.
Housing assembly 211 further includes a plurality of tubular exit stacks 1016 and 1018. Exit stacks 1016 and 1018 have an internal passageway 1005 and 1007, respectively, that is in fluid communication with the evaporation chamber 588 (
Turning now to
Partition wall 556 includes a lower divider 1051 that is water tight to prevent fluid in fluid reservoir 572 from flowing into mechanical room 1038. An upper portion of partition wall 565 bounds one embodiment of furnace 514A having slits 1048 that allow air to pass through and enter evaporation chamber 588. The slits 1048 provide an inlet for outside air to enter evaporation chamber 588 above fluid reservoir 572 and create an air flow path 574. Air flow path 574 extends horizontally within evaporation chamber 588 between slits 1048 and openings 1050, which lead to exit stacks 1016 and 1018. A curved air guide panel 1052 may be provided inside evaporation chamber 588 below opening 1050 to direct the airflow up into exit stacks 1016 and 1018. Panel 1052 is not essential, but can improve the efficiency of the system. A second air flow guide panel 1042 can be provided in mechanical room 1038 to direct air into slits 1048 to improve the efficiency of airflow into furnace 514A.
Air flow path 574 may be produced in whole or in part by one or more blowers configured to force air into and/or pull air out of evaporation chamber 588. The blower can be any device configured to create air flow. In one embodiment, the blower used to produce air flow in path 574 may be a fan, an electrical generator, a thermal oxidizer, a gas powered furnace, as discussed above, and/or the like. The embodiment shown in
As described above with respect to
The source of the forced air and the type of forced air may be selected to provide a desired level of efficiency and to recoup waste heat produced from ancillary systems to the evaporation system 210A. As shown and discussed above with respect to
To increase the evaporation of water from fluid reservoir 572, evaporator 210 can include a misting system 1060. Misting system 1060 may include a plurality of spray nozzles (e.g., nozzles 596) piping 588, and pump 501 as previously discussed with regard to water evaporation system 210. Misting system 1060 produces a fine mist of wastewater that increases the rate of evaporation of wastewater into air flow path 574 as described above with respect to the discussion of nozzles 596. Misting system 1060 can include any number and/or sizes of conduit and/or nozzles configured to spray wastewater into the air above fluid reservoir 572. Additional details regarding spray nozzles can be found in co-pending patent application Ser. No. 12/029,377, filed Feb. 11, 2008, which is hereby incorporated herein by reference.
In a preferred embodiment, wastewater introduced into fluid reservoir 572 is treated to inhibit scaling. In a preferred embodiment, the descaling treatment is carried out without softening the water. The descaling treatment can include lowering the pH, applying crystal forming inhibitors, and/or scaling inhibitors. In one embodiment, fluid reservoir 572 has a pH less than about 7, more specifically in a range from about 4.5 to about 6.5, and even more specifically in a range from about 5 to about 6. Adjusting the pH of the wastewater to a pH lower than about 7 inhibits precipitation of salts and other minerals on the sidewalls and other surfaces within evaporation chamber 588. The pH of the wastewater stream can be adjusted by adding a strong acid such as hydrochloric acid, sulfuric acid, and/or phosphoric acid. The acid can be added into the wastewater within the evaporator or prior to the evaporator. As described more fully below with regard to
The demister typically includes a pattern of walls and channels that allow air to flow therethrough but that cause suspended water droplets to collide and coalesce to form larger water droplets that are heavy enough to fall downward through airstream 1260, which is flowing upward. In alternative embodiments airstream 1260 can flow horizontally or at other angles so long as the collected water can be separated from the evaporated water in airstream 1260.
The size and configuration of the surfaces in the demister and the thickness of the demister (i.e., the length of the flow path through the demister) determines the size and percentage of the water droplets that will coalesce. In general, a longer flow path (i.e., thicker demister) results in a high percentage of a given size water droplet being coalesced and narrower channels and/or thinner wire surfaces results in smaller droplets being coalesced.
First coalescing pad 1262 includes a plurality of wall structures that define channels through which air stream 1260 is forced to flow over. Wall structures 1266 can have any shape suitable for directing airflow. For example, as shown in
The structure of first coalescing pad 1262, which includes wall structures 1266, is configured to remove water droplets of a particular size. For example, the dimensions and spacing of the wall structures 1266 can be configured to remove water droplets with a diameter of about 20 microns to 100 microns or larger. Water coalescing pads having wall structures are typically useful for removing relatively larger water droplets as compared to a wire mesh pad (e.g., water coalescing pad 1268, described below). In one embodiment, the water coalescing pad 1262 has wall structures 1266 with a thickness in a range from about 0.5 mm to about 5 mm and spacing in a range from about 2 mm to about 50 mm, more specifically about 9.5 mm (⅜ inch) to about 12.7 mm (½ inch). In one embodiment, the wall structures 1266 are configured to coalesce water droplets with a diameter in a range from about 20 microns to about 100 microns. The coalescing pad 1262 can include any number of layers of wall structures 1266. The thickness 1263 of coalescing pad 1262 is typically between about 100 mm and 1000 mm, more typically between about 200 mm and 500 mm.
Second water coalescing pad 1268 shown in
The wire mesh of coalescing pad 1268 is typically woven together, although other methods of interconnecting and/or linking the wires may be used. In one embodiment, coalescing pad 1268 includes a plurality of layers of wire mesh. For example, coalescing pad 1268 can include 50-200 layers of woven wire. Moreover, coalescing pad can have layers with different sized wires and/or spacing. For example, in one embodiment, an upstream portion of the coalescing pad 1268 can have a first coarser wire and/or lower surface area and a downstream portion can have a finer wire diameter and/or higher surface area. The thickness 1269 of coalescing pad may be in a range from about 100 mm to about 1000 mm, more typically between about 150 mm and 500 mm.
Examples of suitable coalescing pad that can be used in demisters according to some embodiments of the invention are sold by Amistco Separation Products, Inc. located in Alvin Tex., USA.
The exit stacks 1016 and 1018 preferably include a wetting system 1270 configured to keep a downstream surface 1267 of demister 1296 wet. Any hardware suitable for applying a liquid such as clean water or wastewater to the downstream surface 1267 may be used. In one embodiment, wetting system 1270 include a plurality of conduits (e.g., conduit 1273) that traverse exit stack 1018 near outlet 1002 above demister 1296. The plurality of conduits 1294 each include a plurality of sprayers 1272, such as sprinklers, misters, nozzles, drip lines or other suitable type of water distribution apparatus. The sprayers 1272 are configured to spray the surface area with sufficient water to maintain a wet surface. Wetting system 1270 can be coupled to a water supply using valves, pumps, conduits and other techniques known in the art. In one embodiment, the wetting system 1270 uses wastewater as the water source.
In operation, the sprayers 1272 can be operated continuously and/or at timed intervals and/or at desired flow rates to maintain a desired wetness. In one embodiment, wetting system 1270 is operated periodically to provide periodic water flow into exit stack 1018, while minimizing the extent to which the water flow impedes airstream 1260 through demister 1296. In one embodiment, the interval for wetting surface 1267 is at least about every hour, more specifically at least about every half hour, and even more specifically at least about every fifteen minutes.
Surprisingly, maintaining a wet surface on the demisters can, in many circumstances, substantially impede the escape of salts and dissolved minerals from the evaporator evaporation system 210A without undo restriction on airstream 1260. Using a wetting system 1270 allows the airstream 1260 to carry a higher concentration of water without losing salts at the interface between the demister and the ambient air. Wetting the surface dissolves salt and/or minerals that would otherwise collect on the surface of the demister and gravity can draw the water back into the airstream 1260, where concentrated salts will fall back down into fluid reservoir 572. The use of wastewater to wet the surface of the demisters may also be advantageous because a portion of the water will be evaporated into the ambient air, which further increases the evaporation efficiency of the system.
Demister 1296 can have any shape suitable for placement in exit stack 1018 so long as airflow can be directed through demister 1296. To facilitate flow of the air stream 1260 through demister 1296, the demister can include brackets and expansion hardware that allows the pads 1262 and 1268 to expand and contract without forming gaps between the walls of exit stack 1018 and demister 1296.
The demister 1296 is useful for preventing dissolved salts and minerals from escaping the evaporator system. Water that has been suspended in airstream 1260, but not evaporated, typically contains salts and/or minerals. Water that is actually evaporated (i.e. gaseous) contains very little if any dissolved salts. By retaining water vapor within the evaporator system, the salts and minerals can be more efficiently concentrated and properly disposed of.
The proper air flow and temperature within exit stack 1018 can be maintained using one or more sensors. Evaporation system 210A may include temperature sensors, humidity sensors, pressure sensors, mass air flow sensors and the like either inside or outside the airflow stream (i.e., inside or outside the system).
The present invention also includes methods for evaporating a fluid. In one embodiment, the methods can include all or a portion of the following steps: (i) pooling a fluid within a reservoir that is bounded by an elongated housing, the housing also bounding an air flow path that is disposed over top of and that communicates with the reservoir, the air flow path extending from an air inlet opening in the housing to an air outlet opening in the housing; (ii) creating a flowing air stream wherein air in the environment outside of the housing flows into the air flow path through the air inlet opening, travels along the air flow path so that the air passes over the fluid within the reservoir, and then exits out of the housing through the air outlet opening; (iii) spraying the fluid within the reservoir into the air flow path within the housing and above the reservoir; and (iv) coalescing suspended water droplets in the air stream on a demister upstream from the air outlet opening and downstream from the reservoir, the demister including at least one water coalescing pad configured to coalesce suspended water droplets in the air stream. In one embodiment, the method the step of coalescing suspended water droplets includes removing at least about 50% by weight of water droplets in the air flow stream having a size between about 1 micron and about 20 microns in diameter. More specifically, at least about 80%, 90%, or even at least about 99% of water droplets having a size between about 1 micron and about 20 microns in diameter are removed. Alternatively, or in addition, the method may include the step of coalescing at least about 50% by weight of water droplets in the air flow stream having a size between about 20 micron and about 100 microns. More specifically, at least about 80%, 90%, or even at least about 99% of water droplets having a diameter of about 20 microns to about 100 microns are removed.
The method can also include wetting a downstream surface of the demister. The wetting may be carried out continuously or intermittently. For example, the surface can be wetted at intervals of less than about 1 hour, more specifically at intervals of less than about 0.5 hour, and even more specifically at intervals of less than about 0.25 hour. The method may also include generating electrical power using an electrical generator to produce an exhaust stream; supplying the electrical power to a power grid and/or powering a control unit configured to operate the electrical generator; and using the exhaust stream to create at least a portion of the flowing air stream. In one embodiment, the method can also include regulating the speed of the flowing air stream based on the temperature or humidity within or outside of the housing. This step can be carried out using a control unit and one or more sensors inside and/or outside the housing. This step can be carried out using a control unit and one or more sensors inside and/or outside the housing. The method can also be carried out using any of the features described above with regard to
As mentioned above, the present invention includes systems and methods wherein the well source is a brackish water such as sea water. In this embodiment, the desired product from the systems and methods may be a desalinated water condensed from the airflow stream downstream from the demisters. The evaporated water in airstream 1260 can be condensed downstream from demister 1296 and recovered to produce a desalinated water. The desalinated water may be potable water or an irrigation water. Where potable water is desired, the heat source for evaporation system 210A typically includes a furnace and the exhaust heat from the combustion of highly polluting materials is typically avoided.
The hot moist air exiting evaporator evaporation system 210A at opening 1002 can be directed to any condenser known in the art for condensing evaporated moisture from a humid air supply. For example, moisture can be cooled using a heat exchanger that cools the purified evaporated stream exiting evaporator evaporation system 210A using ambient air and/or a coolant such as water, including sea water. Those skilled in the art are readily familiar with condensers that can be used to produce condensed water from a high moisture content stream such as airstream 1260 downstream from demister 1296. Moreover, those skilled in the art are familiar with systems including pumps, valves, storage tanks, etc. that are useful for handing the desalinated water to obtain it from the ground or a body of water and/or for injecting concentrated water back into the environment. Additional details regarding condensers and systems for drawing brackish water from the natural environment can be found in US Patent Publication No. 2007/0084778 to St. Germain and US Patent Publication No. 2002/0178723 to Bronicki, which are both hereby incorporated herein by reference.
The wastewater stream 106 is treated with polymer 1308 and optionally acid 1310 to form conditioned wastewater stream 1312, which is then delivered to gas induction apparatus 1314. Gas induction apparatus 1314 mixes a gas into stream 1312 to form induction stream 1310. Induction stream 1310 is injected into upflow separator 1304 via inlet 1322. Upflow separator 1304 separates the wastewater stream into a recycle gas stream 1316, volatile organic compounds 1318, a foam stream 1324, a pretreated wastewater stream 1323, and in some cases a solids stream 1336.
In one embodiment, pretreated wastewater stream 1323 can be treated in a second upflow separator 1306 to ensure complete separation. Or, alternatively wastewater stream 1324 can be delivered to water evaporation system 210A via stream 1330. The additional pretreatment of stream 1323 can be selectively controlled by valve 1337. For example, if a certain quantity of solids and/or hydrocarbons remains in stream 1323, valve 1337 can be set to deliver stream 1323 to a second gas induction apparatus 1338 and subsequently to second upflow separator 1306. In an alternative embodiment, pretreatment system can be configured to always deliver stream 1323 to a second upflow separator 1306 or even one or more additional upflow separators to achieve a desired level of separation between the water and hydrocarbons.
The second gas induction apparatus combines stream 1323 with a gas from upflow separator 1306 via line 1344 and/or from ambient air to form a second induction stream 1342, which is then introduced into the second separator 1306 via inlet 1340. A second quantity of polymer 1338 can also be added to stream 1323 to enhance separation of the water and polymer. Second upflow separator 1306 creates a stream 1319 of volatile organic compounds, a foam stream 1326 that includes separated hydrocarbons, a pretreated wastewater stream 1332 and in some cases a second solid waste stream 1334.
The polymer 1308 is added to the wastewater stream 1312 and optionally added to stream 1323 in sufficient quantities to enhance separation of the hydrocarbons and the water fraction of the wastewater. Any polymer can be used that will enhance the interaction of hydrocarbons with the surface of the water. The polymer can be a high or low molecular weight, anionic, or cationic polymer that is water or emulsion soluble. Examples of suitable polymers include polymamines and polyamides (e.g., polyacrylamide). Other flocculents known in the art can be used alone or in combination with the polymer to facilitate separation of the hydrocarbons and the water. The polymer can be continuously metered into the wastewater stream 106 or alternatively a desired quantity can be added in batch to a certain quantity of wastewater to obtain a desired concentration. In one embodiment, the concentration of the polymer in the wastewater is in a range from about 1 parts per million (vol. %) to about 300 parts per thousand (vol. %) more specifically about 2 ppm (vol. %) to about 50 ppm (vol. %), and most preferably about 3 ppm to about 10 ppm. The use of a polymer can have a substantial impact on the separation of hydrocarbons from water. In one embodiment, wastewater departing pretreatment system 116 has a hydrocarbon content less than about 150 ppm, less than about 50 ppm, or even less than about 10 ppm.
An acid may also be metered or batch added to the wastewater stream 1312 to lower the pH. Examples of suitable acids include concentrated hydrochloric acid and concentrated sulfuric acid. Hydrochloric acid may be preferred in some embodiments. The use of an acid to lower the pH of the wastewater stream in combination with the use of a polymer was surprisingly found to increase the separation of hydrocarbons from wastewater in the upflow separator 1304 as compared to polymer alone. However, lowering the pH is not essential for separation in the upflow separator. Moreover, substantial benefits throughout system 100 were observed from adding acid to wastewater stream 106. The use of an acid has been found to substantially reduce buildup of salt and other minerals on the components of system 100, and particularly the components of evaporation system 210 that come into contact with wastewater (including misted wastewater as described above). Thus, while adding acid prior to upflow separator 1304 can be desirable, the addition of acid may also be beneficial in evaporation system 210 or in line between pretreatment system 116 and evaporation system 210. In one embodiment, the acid is added in sufficient quantities to lower the pH to within a range from about 4-7, more specifically about 4.5-6.5, and even more specifically about 5-6. The pH of the wastewater stream can be measured using techniques known in the art (e.g., a pH meter).
The mixture ejected from riser 1458 forms a foam-water mixture that separates based on density into a water fraction 1470, a foam fraction 1468 and a gaseous fraction 1466. Foam fraction 1468 floats above the water fraction 1470 because it is lighter than water. The water fraction 1470 collects near the bottom of vessel 1403. The water level (i.e., the interface between fraction 1470 and 1468) can be maintained by controlling the flow of water out of outlet 1453. If the rate of flow out of outlet 1453 is greater than the accumulation of separated water entering through riser 1458 then the water level rises. Conversely, if the rate of flow out of 1453 is greater than the rate of water accumulation from outlet 1453, the water level drops. The foam fraction 1468 is allowed to accumulate in vessel 1403. The accumulating foam rises above water fraction 1470 until the foam flows over weir wall 1460. Foam flowing over weir wall 1460 flows along a slanted support 1462 and exits vessel 1403 as stream 1324. The top of weir wall 1460 and opening in vessel wall create the opening through which foam flows out of vessel 1403.
Gas fraction 1466 is lighter than foam fraction 1468 and collects in vapor space above weir wall 1460 and exists vessel 1403 as stream 1316 (i.e., gas induction line) or as stream 1318 (i.e., VOCs).
Outlet 1136 can be selectively opened to flush solids that may collect in the bottom of vessel 1403, depending on the presence or absence of solids in wastewater stream 106. One or more sprayers (e.g., sprayers 1450 and 1452) can be provided to facilitate flushing vessel 1403.
The use of polymer and optionally acid enhances the degree and/or rate to which hydrocarbons are separated in vessel 1403. Because foam fraction 1468 has a high surface area, the polymer in the foam is able to better attract hydrocarbons than polymer in the water fraction 1470. This feature can result in rapid separation of the hydrocarbons from the water fraction. This feature results in much higher throughput of material for a given volume of vessel 1403, thereby reducing capital costs and reducing the number of successive upflow separators needed to sufficiently treat the wastewater stream. In some embodiments, sufficient separation can be achieved with a single separation vessel or just two separation vessels, although more than one or two upflow separators can be used depending on the circumstances of the wastewater stream.
In one embodiment, upflow separator 1304 may be efficiently operated by periodically purging foam fraction 1468. Periodically purging foam fraction 1468 prevents vessel 1403 from becoming clogged and improves the separation of gases, solids, water, and foam. To purge foam fraction 1468, water flow through outlet 1453 can be halted or reduced to allow the water level to rise.
In some cases, solids such as small rocks, dirt, and/or sand can accompany the wastewater stream and may collect in the bottom of reactor 1403.
Additional details regarding upflow separator systems that can be used in the present invention include, but are not limited to the features of the upflow separators described in U.S. Pat. No. 4,564,457, which is hereby incorporated herein by reference.
In one embodiment, the invention includes methods for separating oil and gas contaminants from water. In one embodiment, the methods include all or a portion of the following steps: (i) providing an upflow separator apparatus include a vessel defining an internal space having a top end and a bottom end. A riser is positioned within the vessel and is coupled to an inlet thereof and extending upward from the bottom end of the vessel, the riser having one or more injection openings configured to produce a foam from an injection stream; (ii) providing an induction apparatus in fluid communication with the inlet of the vessel and with a wastewater stream; (iii) mixing a polymer with the wastewater stream; (iv) adjusting the pH of the wastewater to less than about 7; (v) inducing gas into the wastewater stream to produce an injection stream; (vi) emitting the injection stream from the injection openings to produce a foam; (vii) allowing the emitted injection stream to separate into a water fraction, a foam fraction, and a gas fraction; (viii) recovering the separated water fraction, foam fraction, and gas fraction; and (ix) introducing the recovered water fraction into a fluid reservoir of a water evaporator, the water evaporator including a housing bounding the fluid reservoir formed at or adjacent to a floor, the housing also bounding an air flow path that is disposed over top of and that communicates with the fluid reservoir; an inlet opening formed at a first location of the housing, the inlet opening being configured to introduce air from outside of the housing into the air flow path; an outlet opening formed at a second location of the housing and communicating with the air flow path, the outlet opening communicating with the open environment outside of the housing; a blower for forcing air into the air flow path and out the outlet opening; and a misting system configured to spray fluid pooled within the reservoir into the air flow path above the fluid reservoir.
The method can employ any of the features described above with respect to the pretreatment system described in
In view of the foregoing, it is appreciated that different embodiments of the present invention can be used to achieve a number benefits. For example, the water evaporation system can be designed to be transportable. As such, the water evaporation system can be shipped directly to a well head, storage tank, pond, or other site where it is desired to evaporate a fluid such as water. The water evaporation system thus eliminates the need to ship the fluid and eliminates the need to pay for disposal fees at a disposal facility. Once use of the system at one location is completed, the system can then be moved to another location. Likewise, if additional capacity is needed, two or more water evaporation systems can be positioned at a single site. In alternative embodiments, it is appreciated that the water evaporation system need not be transportable but can be built as a fixed structure at a desired location.
Additional benefits of the water evaporation system are that some embodiments can be designed to be self-contained for use in remote locations. Furthermore, because housing 220 is enclosed, the system can be used in high winds and in any other environmental conditions. In some embodiments, depending on whether conditions, it is appreciated that the water evaporation system can be used to evaporate more than 200 barrels of water per day and more commonly more than 300 or 400 barrels of water per day. Although the present invention is primarily discussed with the evaporation of water, it is also understood that the inventive water evaporation system can also be used for the evaporation of other types of fluids.
The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. For example, it is appreciated that the different features of wastewater treatments systems 100 and 100A and the alternatives thereof can be mixed and matched to form other system configurations. Thus, the described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.
This application claims the benefit of U.S. Provisional Application No. 61/285,901, filed Dec. 11, 2009, the disclosure of which is incorporated herein by specific reference.
| Number | Name | Date | Kind |
|---|---|---|---|
| 1502911 | Doern | Jul 1924 | A |
| 2268871 | Hall | Jan 1942 | A |
| 2825680 | Stutz | Mar 1958 | A |
| 3703917 | Mundy | Nov 1972 | A |
| 3771289 | Skoli et al. | Nov 1973 | A |
| 3780786 | Pacault et al. | Dec 1973 | A |
| 3939036 | Erwin | Feb 1976 | A |
| 4473438 | Loureiro | Sep 1984 | A |
| 4479486 | Manning et al. | Oct 1984 | A |
| 4534828 | Erickson et al. | Aug 1985 | A |
| 4564457 | Cairo et al. | Jan 1986 | A |
| 4713172 | Horn et al. | Dec 1987 | A |
| 5080802 | Cairo, Jr. et al. | Jan 1992 | A |
| 5082525 | Travis | Jan 1992 | A |
| 5156745 | Cairo, Jr. et al. | Oct 1992 | A |
| 5209821 | Shaw et al. | May 1993 | A |
| 5227018 | Bro et al. | Jul 1993 | A |
| 5240560 | Gregory | Aug 1993 | A |
| 5272820 | Ito et al. | Dec 1993 | A |
| 5335728 | Straham | Aug 1994 | A |
| 5381742 | Linton et al. | Jan 1995 | A |
| 5516434 | Cairo, Jr. et al. | May 1996 | A |
| 5573661 | Rachak | Nov 1996 | A |
| 5582680 | VanKouwenberg et al. | Dec 1996 | A |
| 5591347 | Cairo, Jr. et al. | Jan 1997 | A |
| 6187206 | Bernier et al. | Feb 2001 | B1 |
| 6190498 | Blagborne | Feb 2001 | B1 |
| 6200428 | VanKouwenberg | Mar 2001 | B1 |
| 6272876 | Roberts et al. | Aug 2001 | B1 |
| 6637379 | Hays et al. | Oct 2003 | B2 |
| 7251939 | Walker | Aug 2007 | B2 |
| 20020178723 | Bronicki et al. | Dec 2002 | A1 |
| 20040086816 | Manning et al. | May 2004 | A1 |
| 20050194323 | Ruth et al. | Sep 2005 | A1 |
| 20060000355 | Ogura et al. | Jan 2006 | A1 |
| 20070084778 | St. Germain et al. | Apr 2007 | A1 |
| 20070227674 | Haslem et al. | Oct 2007 | A1 |
| 20070235146 | Haslem et al. | Oct 2007 | A1 |
| 20070246414 | Page et al. | Oct 2007 | A1 |
| 20090199972 | Lakatos et al. | Aug 2009 | A1 |
| 20100044322 | Fujisato et al. | Feb 2010 | A1 |
| 20110139378 | Lakatos et al. | Jun 2011 | A1 |
| Number | Date | Country |
|---|---|---|
| 1 621 520 | Feb 2006 | EP |
| 6-218357 | Aug 1994 | JP |
| 7-88469 | Apr 1995 | JP |
| 2006-7097 | Jan 2006 | JP |
| Entry |
|---|
| PCT/US2010/059941, Dec. 10, 2010, International Search Report dated Aug. 12, 2011. |
| PCT/US2010/059941, Dec. 10, 2010, Written Opinion dated Aug. 12, 2011. |
| Office Action issued May 9, 2012 in U.S. Appl. No. 12/029,377, filed Feb. 11, 2008. |
| Brochure entitled A Simple Solution to Complex H20 Treatment Problems: UNICEL, Induced Gas Flotation Separators, published at least as early as Dec. 10, 2009, 3 pages. |
| Office Action issued Jan. 19, 2011 in U.S. Appl. No. 12/029,377, filed Jan. 1, 2011. |
| Final Office Action issued Aug. 17, 2011 in U.S. Appl. No. 12/029,377, filed Feb. 11, 2011. |
| Office Action issued May 9, 2012 in U.S. Appl. No. 12/029,377, filed Feb. 11, 2011. |
| International Preliminary Report issued Jun. 12, 2012, in PCT Application No. PCT/US2010/059941, filed Dec. 10, 2010. |
| Number | Date | Country | |
|---|---|---|---|
| 20110140457 A1 | Jun 2011 | US |
| Number | Date | Country | |
|---|---|---|---|
| 61285901 | Dec 2009 | US |
