Patent Application
20140262735
Hydraulic fracturing (or “Tracking”) is a well-known process utilized by the oil and gas industry to create and enlarge fractures in underground shale formations. The fractures allow oil and natural gas to move more freely through the shale formations and ultimately flow to the surface. In the fracking process, explosions are set off to create the fractures and then high-pressure fluid is injected into the well in order to perpetuate the fracturing and hold the fractures open.
The fracturing fluid is typically comprised of water containing a proppant and chemical solution mixed therein. The fracturing fluid is often composed of between about 98-99.5% water and sand with the additional chemical solution accounting for about 0.5-2%. The water includes, in significant part, freshwater that must be transported to the well site by tanker truck or piping. The proppant, which is often sand or a similar material, is used to keep the fractures from closing after the injection has stopped. The chemical solution includes a variety of additives having dosage rates that vary with the location and condition of the specific well. These additives may include, but are not limited to, acids (e.g., hydrochloric acid), corrosion inhibitors (e.g., alcohols, organic acids, polymers, sodium salt, glycol and amide), iron control chemicals (e.g., sodium compounds and citric acid), antibacterial agents, biocides (e.g., gluteraldhyde, alcohols, sodium salt, sodium hydroxide and bromide salt), scale inhibitors (e.g., alcohols, organic acids, polymers, sodium salt, glycol and amide), friction reducers (e.g., polymers, hydrocarbons and water soluble polymers), surfactants (e.g., alcohols, glycols and hydrocarbons), gelling agents (e.g., guar gum, hydrocarbons and polymers), breakers (e.g., ammonium persulfate, sodium and potassium salts) and crosslinkers (e.g., polyol and borax).
The fracking process typically requires between about one million and five million gallons of water or more per well. A portion of the water that is injected into the well returns to the surface as “flowback water.” While the flowback water returns to the surface over a period of three to four weeks, most of the flowback water returns within the first seven to ten days. The volume of recovery is generally between about 20-60% of the volume that was initially injected into the well. The rest of the fluid is absorbed in the shale formation. At a certain point, there is a transition from primarily recovering flowback water to primarily recovering “produced water,” which is water naturally occurring in the shale formation that flows to the surface over the life of the well.
Upon returning to the surface and exiting the well, the flowback water and produced water is generally collected in tanks, open pools or lagoons located near the well. From there, the flowback water and produced water is pumped into tanker trucks and transported from the well site to a deep disposal well where the water is placed back into the ground. Each disposal well typically costs several million dollars to drill and maintain. Disposal wells can additionally create environmental and water source contamination concerns.
The flowback water and produced water is typically contaminated with man-made and naturally-occurring substances. The water is contaminated with the spent chemicals that are mixed into the fracking water prior to its injection into the well, as discussed above. The water is also contaminated with naturally-occurring substances residing below the Earth's surface. For example, the water may have elevated levels of Kjeldahl nitrogen, petroleum residue, sodium, ammonia, chloride, sulfate, chloride sulfate, total dissolved solids (TDS), chloride, barium, strontium, boron, benzene, ethylbenzene, toluene, xylene, glycols, 2-butoxyethanol, radionuclides such as radium isotopes (e.g., radium-226 and radium-228), uranium-238 and lead-210 and other naturally occurring radioactive material (“NORM”) found in the shale formations. Additionally, some scientists believe that the explosions occurring during the fracturing of the shale formation set off chain reactions that result in the creation of radioactive material in addition to the NORM already present in the shale formations.
In order for the flowback water and the produced water to be reused as fracturing water or discharged to the environment, it must first be treated. As such, a need exists for a system and method for treating contaminated flowback water and produced water such that it can be reused and the cost and environmental concerns resulting from the disposal wells can be eliminated. A particular need exists for a system and method for removing radioactive materials from flowback water and produced water. A further need exists for a system that is self-contained and is mobile between well sites and may be scaled up or down depending upon the amount and quality of the water to be treated.
One embodiment of the present invention is directed to a water treatment system that includes a filter, an aerator, a hydrogen absorption manifold, a first treatment container, a second treatment container, a boiler, a superheater, a fractional distillation separator and a condenser.
The filter can be in the form of a filter compartment having a material therein suitable for removing chloride ions and transmutated chlorine ions from water passing through said system. The material contained in the compartment may include at least one of coconut carbon, ionized sand and cadmium. The aerator is suitable for oxygenating the water and may be located at an exit end of the filter compartment. The hydrogen absorptive manifold is designed for absorbing hydrogen ions and reducing the pH of the water. The absorptive manifold may be constructed of an outer tube surrounding an inner plate having a plurality of fins extending therefrom. The fins can be constructed from gold, silver, palladium, nickel, zinc, tin, indium and/or copper. The absorptive manifold may also include an electromagnet for controlling electromagnetic radiation.
The first treatment container, which may be in the form of a concrete containment basin, is in fluid communication with the absorptive manifold. The first container may include a voltage accelerator, such as a P dope N dope voltage accelerator, for inducing a charge in said water. The voltage accelerator may include a positively charged plate and a negatively charged plate submerged in the water within the first container. The first container may also include first pollutant collection substrate contained in a hanging bag which may include silicon dioxide, calcium carbonate and/or cadmium. An oil snout may further be included in the first container for capturing oil and benzene molecules from the water. The second treatment container, which may also be in the form of a concrete containment basin, is in fluid communication with the first container and may include a screen therein that includes at least one of nickel and calcium carbonate.
In one embodiment, the system includes a heater comprised of a boiler and a superheater. The boiler may be adapted for converting the water into a saturated steam, while the superheater can be designed to convert the saturated steam to a superheated steam. The superheated steam may be directed to a fractional distillation separator configured for condensing elements, including radioactive elements, by atomic mass units. The fractional distillation separator includes a plurality of internal plates, each having an aperture defined therethrough. Extending upwardly from each aperture may be a pipe that is topped with a dome-shaped cap configured for condensing elements by atomic mass units. The condensed elements may flow from the fractional distillation separator via apertures defined in an outer shell adjacent the caps. The system may further include a condenser in fluid communication with an outlet of the fractional distillation separator for condensing the steam flowing from the fractional distillation separator.
Another aspect of the present invention is directed to a method for treating contaminated water including the steps of: collecting contaminated water, filtering the water to remove hydrogen ions, directing the water through an absorptive manifold to absorb hydrogen ions and inducing a charge in the water with a voltage accelerator. The method may also include the steps of: boiling the water to create saturated steam, heating the saturated steam to convert the saturated steam to a superheated steam, introducing the superheated steam to a fractional distillation separator, separating contaminants from the superheated steam in the fractional distillation separator and condensing the steam upon discharge from the fractional distillation separator.
Other aspects and advantages of the present invention will be apparent from the following detailed description of the preferred embodiments and the accompanying drawing figures.
In the accompanying drawings, which form a part of the specification and are to be read in conjunction therewith in which like reference numerals are used to indicate like or similar parts in the various views:
The invention will now be described with reference to the drawing figures, in which like reference numerals refer to like parts throughout. For purposes of clarity in illustrating the characteristics of the present invention, proportional relationships of the elements have not necessarily been maintained in the drawing figures.
The following detailed description of the invention references specific embodiments in which the invention can be practiced. The embodiments are intended to describe aspects of the invention in sufficient detail to enable those skilled in the art to practice the invention. Other embodiments can be utilized and changes can be made without departing from the scope of the present invention. The present invention is defined by the appended claims and the description is, therefore, not to be taken in a limiting sense and shall not limit the scope of equivalents to which such claims are entitled.
The entire disclosures of pending U.S. patent application Ser. No. 13/627,765, filed on Sep. 26, 2012 to Wayne R. Hawks entitled “Self-Container Irrigation Treatment System” and U.S. Application Ser. No. 13/219,080, filed on Aug. 26, 2011 to Wayne R. Hawks entitled “Self-Container Irrigation Treatment System” are incorporated herein by reference. The terms “contaminated water” and “water,” when used independently of any adjectives herein, shall refer to either one or all of fracking water, flowback water, produced water or other contaminated water treated by the system of the present invention.
As illustrated, the system 10 is normally located adjacent a source of contaminated water 14, which may come directly from a well or may be contained within one or more tanks, barrels, open pools, lagoons or ponds near the well. The source of water 14 may include fracking water, flowback water, produced water, water used in coal production and dust control, water used in coal-fired power plants, water used in nuclear power plants, water from contaminated reservoirs, ponds, rivers and streams or any other source of contaminated water. A pump 16 may be provided to transport the contaminated water into the system 10.
The system 10 may include a filter 18 comprising a canister or compartment 20 that contains coconut carbon (i.e., activated carbon made from coconut shells), ionized sand and cadmium (Cd) for removing chloride and transmutated chlorine ions (Cl−) and absorbing neutrons. The cadmium (Cd) acts as a neutron absorber and the sand, which is silicon dioxide (SiO2), ties up the chlorine ions. An aerator 22 may be placed at the exit end 24 of the filter compartment 20 in order to oxygenate the water as it flows from the filter 18.
A hydrogen absorptive manifold 26 for absorbing hydrogen ions and reducing the pH of the water may be provided in fluid communication with the filter compartment 20. The manifold 26, which is illustrated in more detail in
The system 10 can include a first container 36, such as a concrete containment basin (CCB) or other suitable barrel or tank, that has a P dope N dope voltage accelerator or regulator 38. The first container 36 is in fluid communication with the absorptive manifold 26. As shown in
In one embodiment, the first container 36 also includes a filter 48 which may be in the form of a hanging bag containing pollutant collection substrates such as silicon dioxide (SiO2), calcium carbonate (CaCO3) and cadmium (Cd) to absorb chloride ions (Cl−) and neutrons, including neutrons of barium (Ba). The container 36 can also comprise an oil snout 50 in connection with its discharge orifice or port 52, as shown in
A second container 54, such as a CCB or other suitable barrel or tank, may be provided downstream of and in fluid communication with the first container 36. The second container 54 can include a stainless steel screen filter 56 through which the water passes for absorption separation. The screen filter 56 may further comprise a variety of elements and compounds, such as nickel (Ni) and calcium carbonate (CaCO3).
From the second container 54, the water may be pumped by an electric pump 13 into a return tank 60, which is discussed in more detail below and then into a superheater system that can include a boiler 62 and a superheater 64. The boiler 62 boils the water to create steam, which then flows into the steam superheater 64. Once in the superheater 64, the saturated steam from the boiler 62 is heated to a temperature of between about 600° F. and 1,200° F. to prepare it for fractional separation. In one embodiment, the saturated steam is heated to a temperature of approximately 900° F.
As illustrated in
From the superheater 64, the superheated steam, which may be approximately 900° F., passes into a fractional distillation separator or column 86 through an inlet aperture 88 proximate a lower end of an outer shell 90. The fractional distillation column 86 is schematically illustrated in
Purified steam can flow from an outlet aperture 110 proximate an upper end of the fractional distillation column 86 to into a condenser 112 that may include two or more condensing units 114 organized in series or parallel for increased efficiency. Once condensed, the purified water may be collected in a tank 116, which may have three outlets 118, 120 and 122. A first outlet 118 may be connected to a test tank 124 containing one or more living organisms, such as fish, for observation of the effects of the treated water on the living organisms in order to assist in monitoring the effectiveness of the treatment process by allowing observation of the living organisms' behavior and health in the treated water. A second outlet 120 can be connected to a line 126 that delivers the water back to the return tank 60 discussed above if it is determined that additional processing of the water is necessary for increased purification levels. At this point CO2 or O2 under low pressure may be injected into the return tank 60 through a control orifice for chemical adjustments of the polluted water. The water may be cycled through the boiler 62, superheater 64 and fractional distillation column 86 as many times as necessary to treat the water. The return tank 60 can include a float system (not shown), for example either Model 21 or Model 221 manufactured by ITT/McDonnell and Miller. Depending upon the flow rate of water entering the return tank 60 from the second container 54 and the flow rate of the water entering the return tank 60 from the return line 126, the float system may prohibit flow from either the second container 54 or return line 126. Typically, if the combined flow rates exceed the system's capacity, flow from the container 54 is prohibited or restricted if necessary. A third outlet 122 is connected to an exterior faucet 128 for connection to a tank truck or directly back to the fracking water supply system for reuse.
It will be appreciated that the system 10 of the present invention can be suitable for treating any water, not just fracking water, flowback water and produced water from hydraulic fracturing operations.
The present invention is also directed to a method of treating contaminated water using the system 10. In the method, the contaminated water is first collected and directed to the system 10. The water may then be filtered to remove chloride and transmutated chlorine ions therefrom. Next, the water may be directed through a hydrogen absorptive manifold 26 to absorb hydrogen ions. After that, the water can be directed through a first treatment container 36, induced with a charge from a voltage accelerator 38, exposed to pollutant collection substrates and passed through an oil snout 50. The water may then be passed through a second treatment container 54 and a screen 56 container therein.
In another aspect of the method, the water may be boiled to convert it to a saturated steam and the saturated steam may then be converted to a superheated steam. The superheated steam may be introduced to a fractional distillation separator 86 where contaminants, such as heavy metals and radioactive elements, may be removed therefrom. Upon exiting the fractional distillation separator 86, the steam may be condensed back to water in a condenser 112 and discharged from the system 10.
Another aspect of the present invention is directed to the configuration of one or more of the systems 10. Multiple systems 10 may be placed in series or parallel. The system 10 is readily scalable by adding similarly equipped trailers 12 to the system 10. When multiple trailers 12 are utilized, some of the system's 10 components may be located on one trailer 12, while other of the system's 10 components may be located on other trailers 12.
As illustrated in
As demonstrated in
Upon the water being treated at the central plant 136, the water may transported back to other well sites 130, for example via the pipes 142, 140 and 138, for use in the fracking process at those other well sites 130. In other words, the treated water may leave the central plant via a pipe 142, arrive at a first satellite center 146, be directed from the first satellite center 146 to a second satellite center 144 via a pipe 140, and then be directed from the second satellite center 144 to a well site 130 that is ready for fracking via a pipe 138. As such, the water may be used at one well site 130, be treated at the central plant 136, and then used again at another well site 130 upon treatment. Alternatively, the treated water may be discharged from the central plant 136 to a stream or other body of water or otherwise transported from the central plant 136 upon treatment.
From the foregoing, it will be seen that this invention is one well adapted to attain all the ends and objects hereinabove set forth together with other advantages which are obvious and which are inherent to the structure. It will be understood that certain features and sub combinations are of utility and may be employed without reference to other features and sub combinations. This is contemplated by and is within the scope of the claims. Since many possible embodiments of the invention may be made without departing from the scope thereof, it is also to be understood that all matters herein set forth or shown in the accompanying drawings are to be interpreted as illustrative and not limiting. It will also be appreciated the components of the system need not be in the order shown in the figures and described above. Rather, depending upon the water to be treated, the components may be aligned or arranged in a different order. In some embodiments, some of the components may be bypassed if certain types of treatment are not necessary. In other embodiments, the water may be cycled through one or more of the components multiple times in order to achieve necessary purification levels.
The constructions described above and illustrated in the drawings are presented by way of example only and are not intended to limit the concepts and principles of the present invention. Thus, there has been shown and described several embodiments of a novel invention. As is evident from the foregoing description, certain aspects of the present invention are not limited by the particular details of the examples illustrated herein, and it is therefore contemplated that other modifications and applications, or equivalents thereof, will occur to those skilled in the art. The terms “having” and “including” and similar terms as used in the foregoing specification are used in the sense of “optional” or “may include” and not as “required”. Many changes, modifications, variations and other uses and applications of the present construction will, however, become apparent to those skilled in the art after considering the specification and the accompanying drawings. All such changes, modifications, variations and other uses and applications which do not depart from the spirit and scope of the invention are deemed to be covered by the invention which is limited only by the claims which follow.
This Application claims priority to U.S. Provisional Patent Application Ser. No. 61/779,668, filed on Mar. 13, 2013, to Wayne R. Hawks entitled “System and Method for Treating Fracturing Water,” currently pending, the entire disclosure of which is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 61779668 | Mar 2013 | US |
