Water Treatment From Fracing and Other Sources

Debate over the the geotechnical technique known as hydraulic fracturing (aka, “fracing” or “fracking”) continues. Much of the expressed concern focuses on perceived potential for groundwater contamination. Some of this ignores the fact that the fracing fluid is injected multiple thousands of feet below groundwater aquifers and that the potential for contamination may be related to improper or faulty well linings. Other concerns are directed toward the nature of chemicals used in the fracing fluid. See our earlier Inkling posts here, here, and here.

Jerome Angelilli (Irving, TX) and four co-inventors were awarded patent US 8,211,296 on July 3, 2012 for their “Portable water treatment system and apparatus”. The patent, assigned to NCH Ecoservices, LLC (Irving, TX), was issued under the USPTO Green Tech Pilot Program, analyzed in Way Better Patents' USPTO Green Technology Pilot Program Discovery and Analysis Report. Their invention is found in the Way Better Patents  Water Index.

The abstract provides a succinct summary of Angelilli et al.’s invention:

"A portable water treatment system and apparatus is disclosed that can effectively and efficiently treat aqueous fluids by quickly and reliably adjusting and controlling the free residual level of disinfectants, contaminants or additives through the addition of one or more treating agents such as oxidizing chemicals and/or other special-purpose additives, and that can continuously store, log, retrieve and report the related fluid composition data and other operating parameters on a real-time basis at either the use site or a remote location. A preferred use for the subject system and apparatus is managing the chemistry of disinfectant, contaminant and/or additive levels in aqueous fluids used in hydraulic fracturing operations, and controlling the free residual levels of the disinfectant or contaminants within the fluids, including fluids maintained in frac tanks during temporary cessation of a hydraulic fracturing operation."

They envision other uses for the portable water treatment system, including industrial cooling water, HVAC cooling water, fruit and vegetable wash water, or poultry wash water, primary and secondary disinfecting of potable water, and treatment of aqueous fluids for subsurface applications such as disinfection, drilling, fracturing, well stimulation, sour well conversion, and well cleanout. Their oxidizer of choice is chlorine dioxide; this compound is also used for bleaching wood pulp, bleaching flour, and municipal water disinfection.
A multiple-use portable water treatment system that can help improve the quality of flowback from fracing operations. This is a good example of clean tech.

The inventors received a new patent on the same technology - 8,226,832

A Piece of the Clean Domestic Energy Puzzle

Way Better Patents patentECO clean tech ecosystem focuses on inventors, innovations, invention, and patents in clean technology. Major inventive domains consist of seven patentECO Indexes:

• Agriculture
• Air
• Energy
• Extraction & Harvesting
• Industry
• Transportation
• Water

Curiously, the USPTO’s Green Tech Pilot Program has issued very few patents in the Extraction and Harvesting Index. One of these is US 8,162,049 issued in April 2012 to Peter E. Rose (Salt Lake City, UT) and assigned to the University of Utah Research Foundation. Mr. Rose’s invention, “Injection-backflow technique for measuring fracture surface area adjacent to a wellbore,” provides techniques for using tracer materials as a measurement tool to provide data for an underground reservoir fluid flow model. The model calculates fracture surface area resulting from hydraulic fracturing and geothermal formation stimulation. Increased surface area of fractures correlates with increased energy extraction rates.

The invention is summarized in Claim 1:

A method, comprising:
measuring an initial temperature profile along the length of a wellbore;
  

injecting a tracer composition into the wellbore at an initial concentration, wherein the tracer composition includes a first thermally reactive tracer and a second thermally reactive tracer, wherein the second thermally reactive tracer is less thermally reactive than the first thermally reactive tracer;
 

allowing the tracer composition to diffuse within a subterranean reservoir for a time;
measuring a second tracer concentration of the second thermally reactive tracer and a first tracer concentration of the first thermally reactive tracer as a function of time; 
and

calculating a reservoir fracture surface area using the second tracer concentration and the first tracer concentration and thermal decay information of the first thermally reactive tracer and the second thermally reactive tracer.

Claims 4 through 6 provide the types of tracers to be used; these include:

• deuterated water, alkali metals, alkaline-earth metals, halides, and combinations thereof
• 2,6-naphthalene disulfonate
• esters, amines, aryl halides, rhodamine WT, eosin Y, dyes, halogenated fluoresceins, and combinations thereof.

Finally, the subterranean reservoir to which this measurement technique may be applied includes a geothermal reservoir, gas reservoir, oil reservoir, or combination thereof. In other words, the method can be applied to the hydraulic fracturing (aka fracing or fracking) method used in shale gas fields such as the Marcellus and Utica shales.

Mr. Rose’s Figure 1 shows a general engineered geothermal system (EGS 100) including a single injection well 110 and two production wells 120A and 120B. A fluid can be injected into the injection well where the fluid travels through fractures 130 in the adjacent formations outward towards the production wells. In the case of heat recovery, the fluid is heated via natural underground thermal sources 140. The production wells are located such that the heated fluid can be recovered and directed to a suitable heat transfer mechanism for producing power or the like, e.g. steam turbines 150. As the inventor points out, the same hydraulic stimulation method can increase production of any well-based production of energy and/or materials (e.g. natural gas, oil, and the like).

Inventor Rose is one of the innovators whom we can thank for helping to unlock US underground energy sources, provide more efficient means for extracting those resources, and reducing the price of energy for all of us.

A footnote: claim 15 states that “the reservoir fluid flow model is run in a numerical simulation program.” Although the USPTO did not provide a software-related cross reference classification for this claim it refers specifically to software. There has been a steady drumbeat by many bloggers and commentators that software should not be patented. Software, however, is intellectual property, and deserves protection via patents, as do the myriad of other types of inventions found in the patentsphere.