US20100072059A1

US20100072059A1 - Electrolytic System and Method for Enhanced Radiological, Nuclear, and Industrial Decontamination

Info

Publication number: US20100072059A1
Application number: US12/237,519
Authority: US
Inventors: Michael J. Peters; David D. Faulder; John D. Breedlove
Original assignee: Peters Michael J; Faulder David D; Breedlove John D
Current assignee: Strategic Resource Optimization Inc
Priority date: 2008-09-25
Filing date: 2008-09-25
Publication date: 2010-03-25
Also published as: CA2738547A1; WO2010036926A3; JP2012503547A; WO2010036926A2; EP2342374A2

Abstract

The present electrolytic system for decontaminating a contaminant disposed on a substrate includes means for providing a brine solution; means for providing a pair of electrodes interposed by a permeable membrane to create a first channel and a second channel; means for flowing the brine solution through the first and second channel; means for applying a potential to the pair of electrodes to produce a first ionized decontamination solution in the first channel and a second ionized decontamination solution in the second channel; means for applying one of the first ionized decontamination solution and the second decontamination solution to the contaminant; and means for recovering the at least one of the first ionized decontamination solution and the second ionized decontamination solution and the contaminant from the substrate.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of prior U.S. patent application Ser. No. 11/603,659, filed Nov. 22, 2006. The entirety of this aforementioned application is incorporated herein by reference.

FIELD OF THE INVENTION

This invention relates to decontamination of substrates, and more particularly decontamination of radiological, nuclear, and industrial contaminants from a wide range of substrates.

BACKGROUND OF THE INVENTION

It has been a problem in the field of radiological, nuclear, and industrial (“RNI”) response and decontamination to provide an efficient and effective decontamination solution that is cost effective and logistically feasible. Some of these problems include health and safety considerations, life cycle costs, ease of use, logistical issues of transportation and storage, and performance factors. The majority of the current radiological decontamination solutions utilize traditional chemical components to attempt decontamination of various substrates. This approach has numerous problems and limitations, including: excessive cost of the formulations and impacts to lifecycle costs; ineffectiveness and decontamination chemicals on a wide range of substrates and isotopes; the need for cumbersome chemical adjustments to address varied isotopes (contamination) and substrates; significant logistical burden including transport, storage requirements and limited shelf life, the associated burden of handling out of date or expired chemicals; the inability to effectively remove and capture isotopes that have become bonded or “fixed” to the substrates; and the inability to effectively deploy and recover solutions on the scale of a major urban center.
Overcoming the challenges of effective decontamination has been attempted. Some of the efforts include primitive decontamination approaches, such as high and ultra-high pressure water applications, scabbling, needle guns, concrete shavers and grinders, in combination with various types of grit, sponge, and carbon dioxide blasting. Some newer approaches include laser ablation, electro-chemical wands, clay absorption, and biological/enzyme based approaches. One of the more popular methods is to use a wide range of products from acid/alkaline compounds to complex formulations, both of which may include sequestering components.

BRIEF SUMMARY OF THE INVENTION

The above-described problems are solved and a technical advance achieved in the field by the present Electrolytic System and Method For Enhanced Radiological, Nuclear, and Industrial Decontamination (termed “Electrolytic Decontamination System” herein), which provides the ability to generate decontamination solutions that are precisely designed to effectuate the release of specific isotopic or other contaminants from a wide range of substrates as needed, and that can be easily adjusted in the field to work on multiple contaminant and substrate matrices and solve many of the problems noted above. Additionally, a sanitizing agent can be produced by the Electrolytic Decontamination System, if desired, using the same system for the generation of hypochlorous acid and/or other sanitizing agents, such as chlorine dioxide, as described by U.S. Pat. No. 3,819,329 issued to Kaestner et al., herein incorporated by reference, which may be generated using similar approaches in order to effectuate chemical and biological decontamination with the Electrolytic Decontamination System.
In one embodiment, the Electrolytic Decontamination System may use a series of typically dry compounds, in conjunction with equipment modifications that can be integrated into existing fielded decontamination equipment. This results in the ability to generate effective on-demand decontamination solutions at a low cost and with minimal logistical burdens. These solutions can be adjusted in the field to have variable oxidative/reductive states that address the mechanisms needed for successful decontamination of various contaminant matrices and substrates.
In another embodiment, the Electrolytic Decontamination System may use surfactants, sequestering agents, nano-particles, tacking materials, and/or other compounds to support the various mechanisms required for successful decontamination. In one aspect, the deployment of on-demand decontamination solutions may also be enhanced by the addition of foaming surfactants. These enhancements may include expansion of the foam solution, thus providing a greater area of coverage per liquid volume, durability, and insulation properties of foam. The foam solutions and/or resulting foam may assist keeping the decontamination solutions wet against a particular contaminated surface, resulting in enhanced contaminant removal. Further, the foam's ability to adhere to vertical and inverted surfaces and the visual aspects of foam to assist as a visual marker for application coverage further provides for enhanced contaminant removal by the decontamination solutions.
The Electrolytic Decontamination System provides the ability to store materials in a dry or other highly concentrated state until deployed for application, which significantly reduces the logistical burden, minimizes storage requirements, and nearly eliminates shelf life issues. The flexibility of the decontamination solution conditioning subsystem of the Electrolytic Decontamination System allows for easy adjustment for field operations and changing conditions. By generating decontamination solutions on-demand, the cost per volume generated is kept to a minimum, thus providing substantial cost savings over current technologies.
The Electrolytic Decontamination System provides for improved decontamination by directly altering the electrochemical state of contaminants and changing the Zeta potential at the contaminant-surface interface. Decontamination solutions are ionized prior to utilization by the addition or removal of electrons (depending on application) by the Electrolytic Decontamination System. The Electrolytic Decontamination System uses an ionized decontamination solution to release/recover contaminants from surfaces, for example.
The Electrolytic Decontamination System directly acts on the electrochemical charge balance between the contaminant/substrate interface to reversibly alter the electrochemical potential and overcome the technical impediments to efficiently increase decontamination effectiveness. The Electrolytic Decontamination System directly modifies the electrochemical properties of introduced or connate water to decontaminate surfaces and increase the decontamination efficiency by controlling the electrochemical charge between the contaminant and a particular surface.
In one embodiment, the present Electrolytic Decontamination System controls the electrochemical state of contaminated surfaces by ionizing a decontamination solution prior to its application to decontaminated surfaces. The ionized decontamination solution may use either a negative or reducing potential (excess of electrons) or a positive or oxidizing potential (lack of electrons), and the amount of charge can be adjusted to control a recovery or other operation. A decontamination solution conditioning subsystem generates both solutions from the split stream exiting the ionizer subsystem. The electrical potential of the decontamination solutions may be controlled by adjusting current density, total dissolved solids, plate size and type, membrane type, voltage, fluid residence time, or a combination of these variables. This allows “tailoring” the decontamination solution potential to maximize the decontamination efficiency of the target contaminant within a lower operating cost structure.
In one embodiment, the present electrolytic system for decontaminating a contaminant disposed on a substrate includes means for providing a brine solution; means for providing a pair of electrodes interposed by a permeable membrane to create a first channel and a second channel; means for flowing the brine solution through the first and second channel; means for applying a potential to the pair of electrodes to produce a first ionized decontamination solution in the first channel and a second ionized decontamination solution in the second channel; means for applying one of the first ionized decontamination solution and the second decontamination solution to the contaminant; and means for recovering the at least one of the first ionized decontamination solution and the second ionized decontamination solution and the contaminant from the substrate.
In another embodiment, the present A system for decontaminating a contaminant disposed on a substrate including a source of brine feedstock; a decontamination solution conditioning subsystem including a pair of electrodes interposed by a permeable membrane to create a first channel and a second channel; a source of electricity for applying a potential to the pair of electrodes to produce a first ionized decontamination solution in the first channel and a second ionized decontamination solution in the second channel; an application unit for in fluid communication with the decontamination solution conditioning subsystem for applying one of the first ionized decontamination solution and the second ionized decontamination to the contaminant disposed on the substrate; and a recovery unit for recovering the at least one of the first ionized decontamination solution and the second ionized decontamination solution and the contaminant from the substrate.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the features and advantages of the present invention, reference is now made to the detailed description of the invention along with the accompanying figures in which corresponding numerals in the different figures refer to corresponding parts and in which:

FIG. 1 illustrates a plan view of an Electrolytic Decontamination System according to an embodiment of the present invention;

FIG. 2 illustrates a plan view of an Electrolytic Decontamination System according to another embodiment of the present invention;

FIG. 3 illustrates a perspective view of a mobile Electrolytic Decontamination System of FIG. 2 according to an embodiment of the present invention;

FIG. 4 illustrates a perspective cutaway view of a decontamination solution conditioning subsystem of the Electrolytic Decontamination System of FIGS. 1-3 according to an embodiment of the present invention;

FIG. 5 illustrates a perspective cutaway view of the ionization unit of the decontamination solution conditioning subsystem of FIG. 4 according to an embodiment of the present invention;

FIG. 6 illustrates an enlarged perspective cutaway view of portion A of the ionization unit of the decontamination solution conditioning subsystem of FIG. 5 according to an embodiment of the present invention;

FIG. 7 illustrates two electrode plates and a semi-permeable membrane of an ionization unit of FIGS. 5 and 6 according to an embodiment of the present invention;

FIG. 8 illustrates a perspective view of a power supply conditioning and networked control interface unit of the decontamination solution conditioning subsystem of FIG. 4 according to an embodiment of the present invention;

FIG. 9 illustrates an exposed perspective view of the power supply conditioning and networked control interface unit of the decontamination solution conditioning subsystem of FIG. 4 according to an embodiment of the present invention;

FIG. 10 illustrates a cross-section view of a recovery unit and vacuum unit according to an embodiment of the present invention;

FIG. 11 illustrates the Zeta potential at a contaminant/substrate interface and a charge distribution of a porous media according to an embodiment of the present invention;

FIG. 12 illustrates a flow diagram of an exemplary process for decontaminating a contaminant from a substrate according to an embodiment of the present invention;

FIG. 13 illustrates a flow diagram of an exemplary process for decontaminating a contaminant from a substrate according to another embodiment of the present invention; and

FIG. 14 illustrates a flow diagram of an exemplary process for decontaminating a contaminant from a substrate according to another embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Where contaminant/substrate active charges begin to dominate, the accommodation of surface charge and the charge of the contiguous fluids influence wettability at the contaminant/substrate interface. This interface has a width approximately several molecular dimensions where charge between the surface and the fluid is called the Zeta potential (“ζ-potential”) charge boundary. Changes in wettability occur due to deliberate manipulation at the contaminant/substrate surface with reversible changes in ζ-potential as an electrochemical factor for improved decontamination efficiency.

DEFINITIONS

In order to ensure a proper understanding of the present Electrolytic Decontamination System, the following definitions are provided to clarify the terminology as used herein.
Carrier fluid—water, brine, or other fluid substance that can be treated and introduced to alter the electrochemical state of the contaminant/substrate interface.
Zeta potential (ζ-potential)—the charge that develops at the interface between a contaminant and a surface. This potential, which is measured in millivolts, may arise by any of several mechanisms. Included among these are the dissociation of ionogenic groups in the particle surface and the differential adsorption of solution ions into the surface region.
Oxidation—Reduction potential (Redox potential, or ORP)—a quantitative measure of the energy of oxidation or reduction. Oxidation is equivalent to a net loss of electrons by the substance being oxidized, and reduction is equivalent to a net gain of electrons by the substance being reduced. The oxidation-reduction reaction involves a transfer of electrons. The oxidation-reduction potential may be expressed as the ability to give or receive electrons and is expressed in terms of millivolts (mV) which may be either positive (lack of electrons) or negative (excess of electrons).
Ionizer—Any device that has the ability to ionize fluids above or below a baseline potential. The configuration of an ionization apparatus may include systems using simple electrolysis with or without a membrane (e.g., ported systems or other configurations), variations in plate configurations, types or materials, or any other embodiment that is able to produce an ionized fluid adequate to generate beneficial results during the extraction/deposition process.
Smearable (Loose) Contamination: Contamination located on or near the substrate surface without being electrostatically bound to it. Loose contamination is normally easily removed and is easily spread by air movement or other means.
Fixed Contamination: Contamination electrostatically bound to a substrate. The strength of the bond is normally related to the specific contaminant and substrate.
Substrate: Any surface such as concrete, stone, tile, metal, asphalt, glass, or plastic that may become contaminated.
Sequestration material: A wide range of natural or man made chelating/sequestering materials such as fulvic acid, citric acid and/or various chemicals, clays and polymers that act to grab and hold a contaminant, and not allow it to reattach to the substrate.
Surfactant: Any compound or combination of compounds that assists in lowering the surface tension and/or increasing the wettability of a fluid to assist in decontamination applications.
Nano-particles: Any man-made or naturally occurring material that can be used to enhance the charge carrying ability of an electrolyzed fluid, including Carbon Nano-tubes, Bucky Balls, various chemical compounds, clays, and certain metals among others.
Electrolysis System: Any device that has the ability to ionize fluids above or below a baseline oxidation/reduction potential. The configuration of an electrolysis apparatus may include systems using simple electrolysis with or without a membrane (such as ported systems or other configurations), variations in plate configurations, types or materials, or any other embodiment that is able to produce an ionized fluid adequate to generate beneficial results during the decontamination process.

Overall System

Referring to FIG. 1, an embodiment of the Electrolytic Decontamination System 100 is shown. Electrolytic Decontamination System 100 includes a decontamination solution conditioning subsystem 102 that ionizes the decontamination solution prior to applying the ionized decontamination solution to a contaminated substrate. Decontamination solution conditioning subsystem 102 is in fluid communication with a catholyte storage vessel 104 and/or an anolyte storage vessel 106 via conduits or pipes 110 and 108, respectively, for later processing or application of the decontamination solution as described further herein. In another aspect, decontamination solution conditioning subsystem 102 may be in direct fluid communication with catholyte storage vessel 104 and/or anolyte storage vessel 106 without pipes 108 or 110. Electrolytic Decontamination System 100 may further include an electrolysis brine proportioner 112 that is in fluid communication with a fluid supply vessel 114 via a conduit or pipe 116. Electrolysis brine proportioner 112 proportions, meters, and/or pumps the fluid contained in the fluid supply vessel 114 for feeding a fluid, such as water, to decontamination solution conditioning subsystem 102. In one embodiment, electrolysis brine proportioner 112 includes a proportioner 122 and a pump 126 that proportions and/or mixes and then supplies the decontamination solution to decontamination solution conditioning subsystem 102 as further described herein.
Additionally, electrolysis brine proportioner 112 may be in fluid communication with a brine storage vessel 118 via conduit or pipe 120. In one aspect, electrolysis brine proportioner 112 maybe in direct fluid communication with brine storage vessel 118 without pipe 120. In one embodiment, electrolysis brine proportioner 112 proportions, meters, and/or pumps a desired concentration of fluid, such as water, received from fluid supply vessel 114 with the brine solution contained in brine storage vessel 118, for example. This proportioned concentration of fluid and brine solution is then fed into decontamination solution conditioning subsystem 102 via conduit or pipe 126. The fluid that is contained in fluid supply vessel 114 maybe provided by a reverse osmosis/filtration unit 128 that may be supplied the fluid from a fluid source 132 via conduit or pipe 130. Reverse osmosis/filtration unit 128 may be any type of apparatus or device that is capable of providing a source of fluid of a desired purity or composition as is known in the art. Further, fluid source 132 may be any type of source of a fluid, such as a tank storage vessel, lake, river, and/or any other type of source of fluid, such as water. In another embodiment, the fluid supplied by fluid supply vessel 114 to electrolysis brine proportioner 112 may be contained or stored on Electrolytic Decontamination System 100, thus not requiring fluid source 132 or pipe 130.
Electrolytic Decontamination System 100 may further include a brine composition proportioner unit 134 that includes one or more meters and/or proportioners 136 and a pump 138 for providing a brine solution to brine storage vessel 118 for storage and further use as described herein. In one embodiment, proportioners 136 may be fed to a supply of brine feedstocks that may be stored in one or more brine feedstock storage vessels 140 a, 140 b, 140 c, and 140 d (collectively 140). Brine feedstock storage vessels 140 a, 140 b, 140 c, and 140 d may individually contain a different brine feedstock that is fed into proportioners 136. Brine feedstock storage vessels 140 a, 140 b, 140 c, and 140 d may be supplied in serial or parallel to proportioners 136, as desired.
Electrolytic Decontamination System 100 dissolves one or more brine feedstocks, which may be one or more salts, at specified rates and are then flowed through contaminant solution conditioning subsystem 102 that “ionizes,” “electrolyzes,” or otherwise embarks a “charge” (ORP) into the solution. Brine feedstock storage vessels 140 may store one or more brine feedstocks that are used to generate electrochemically altered decontamination solution, such as sodium chloride, potassium chloride, potassium nitrate, sodium nitrate, sodium phosphate, potassium phosphate, sodium sulfate, potassium sulfate, for example. Other applicable salts (and/or combination of these or other salts) may be used to produce a decontamination solution with sufficient characteristics to carry a charge as described herein. Brine feedstock will disassociate and form various acids and bases for decontamination activities. These brine feedstocks may be used at concentrations that vary from a few parts per million to over 10%, depending on the application. In one embodiment, brine feedstocks that are stored in brine feedstock storage vessels 140 may be in a liquid or solid form for ease of use at remote locations.
Contaminant solution conditioning subsystem 102 produces the initial acids and bases for the decontamination activities from the brine feedstocks, in one embodiment. For example, hydroxides such as NaOH and KOH may be derived from their basic salts. Further, conjugate hypochlorous/hydrochloric acids may also be made from these salts. A solution of nitric acid may be produced in a similar fashion by starting with either potassium or sodium nitrate salts, which can also generate their conjugate bases. These decontamination solutions may be generated together or separately depending on the application. The ORP of these decontamination solutions may be in the range of a few millivolts (mv) to over ±1150 mv, depending on application, for example.
Electrolytic Decontamination System 100 may also include one or more post electrolysis additive storage vessels 142 a and 142 b (collectively 142) for storing one or more decontamination additives, foam modifiers, and the like that may be supplied to the decontamination solution after it has been ionized in decontamination solution conditioning subsystem 102 as further described herein. Storage vessels 142 may further store surfactants, chelants or other materials that are post-injected into the deployment stream of generated decontamination solution. For example, the addition of nano-particles (natural or man-made) or other suitable materials may be used or added to the decontamination solution to enhance its ability to retain and/or carry a charge or otherwise enhance the carrying capacity of the decontamination solution. Some exemplary materials include: Bucky Balls, carbon nano-tubes, graphite, silicates, various clays or other (natural or manmade) materials that can assist in carrying a charge to enhance decontamination activities. Preferably, these materials are typically added at a rate between 0.01% to over 5%, depending on the materials utilized and the applications.
The bonds between contaminants and substrates are commonly electrostatic in nature, and the ability to modify the potential of the decontamination solution plays an important role in the ability to satisfy these bond charges and release the contaminants from the underlying substrates. Thus, breaking the electrostatic bonds that hold fixed contaminants to a substrate is an important step in the removal of fixed contamination. The ability to control the ORP of the fluids provides a means to adjust decontamination solutions as needed to address various contaminant and substrate matrices.
The present Electrolytic Decontamination System controls the electrochemical state of the subject substrate by electrochemically altering a decontamination solution prior to its application onto the substrate. This electrochemically altered decontamination solution can use either a negative or reducing potential (excess of electrons) or a positive or oxidizing potential (lack of electrons), and the amount of available charge can be adjusted to control the decontamination operation. A split cell electrolysis device will generate both of the solutions, as described herein, from the split stream exiting the electrolysis subsystem. The electrical potential of the solutions can be controlled by adjusting current density, Total Dissolved Solids (TDS), salinity, ionic constituents, plate size and type, membrane type, voltage, fluid residence time, or a combination of these variables. This allows “tailoring” the decontamination fluid potential to maximize the decontamination efficiency of the decontaminant within a lower operating cost structure, on a wide variety of contaminants and substrate materials.
The present Electrolytic Decontamination System also adjusts and controls the pH of the decontamination solution to improve efficiency of the decontamination process. Increasing the reducing potential typically results in a greater pH of the decontamination solution (more alkaline). Conversely, lowering the reducing potential typically results in a lower pH of the decontamination solution (more acidic). These fluids may be modified with various buffering compounds to assist in contaminant removal.
The addition of surfactants may be needed to address issues of capillary penetration where contaminants may be entrapped. Various surfactants are used to decrease surface tension and reduce the contact angle between the wetting phase the substrate. This allows for penetration into subsurface capillaries and surface irregularities, and assists in the delivery of the electrochemically altered fluid to satisfy the bonding potential of the contaminant to the substrate. These surfactants may be cationic, anionic or nonionic. The surfactants are specifically chosen to work synergistically with the charged fluids. The surfactants and/or dispersants may be added in concentrations ranging from 0.05% to well over 10% depending on the application. Although many surfactants/dispersants can be used for this application some exemplary surfactants/dispersants include: lignal sulfonates, octyl phenols, nonyl phenols, amine oxides (such as decyl-dimethylamine oxide or N-dialkylmethylamine oxide), Tomadyne 102, or ethoxalated alcohols. The surfactants/dispersants may be stored in storage vessels 142, for example.
Referring now to FIG. 2, an embodiment of the Electrolytic Decontamination System 200 is shown. Electrolytic Decontamination System 200 is a mobile embodiment that may include a vehicle 202 for mounting and transporting the Electrolytic Decontamination System 200 to a particular decontamination site. Vehicle 202 may be a self-propelled vehicle or one that is propelled by another vehicle. Additionally, the apparatuses, devices, units, and the like noted on vehicle 202 are an exemplary orientation of these things. Further, although fluid source 132 and pipe 130 are not shown in Electrolytic Decontamination System 200, they may be present in one embodiment. Mounted on vehicle 202 are many of the apparatuses, devices, subsystems, and units as shown in Electrolytic Decontamination System 100 with identical reference numerals. In addition to that described with regards to Electrolytic Decontamination System 100, Electrolytic Decontamination System 200 may further include a compressed air foam unit 204 for providing the decontamination solution in a compressed foam application. Compressed air foam unit 204 may also include pneumatic pumping systems and/or air injection for expanded foam applications and/or other pumping systems such as centrifugal pumps. Compressed air foam unit 204 may be supplied a source of compressed air from a compressor/generator unit 208. Some exemplary compressed air foam units 204 may be found in U.S. Pat. No. 6,155,351 issued Dec. 5, 2000 and U.S. patent application Ser. No. 11/105,290 published Apr. 13, 2005, both of which are incorporated herein by reference. Compressor/generator unit 208 may further provide electricity for the operation of the other apparatuses and units located on vehicle 202, such as decontamination solution conditioning subsystem 102, proportioners 136, reverse osmosis/filtration unit 128, proportioner 122, and the like. Various foaming agents, polymers, gel agents, etc., may also be added to provide logistical advantages as described above. These advantages include the ability to cling to vertical and inverted surfaces and the ability to encapsulate micro-particles. Clinging foam will also retard the migration of particles into porous building materials.
The capillary rise effect maybe used to assist in the removal of contaminants embedded deep in porous media. This is typically accomplished by creating a gas (such as CO₂) in the pore structure that will displace liquids and isotopes from pores and capillaries. A wide range of compounds may be added to the electrochemically altered fluids to assist in creating a capillary rise effect to ‘push’ released contaminants out of capillaries. For example, on alkaline substrates such as concrete, acids are commonly used to invoke this mechanism. One example is the addition of citric acid for this process, which can be added to the oxidizing fluid in varying amounts depending on the substrate porosity and contaminants present.
Electrolytic Decontamination System 200 may also include a discharge/spray apparatus 206 that may include a hose 210 for applying decontamination solution 212 to a substrate 214, for example. Discharge/spray apparatus 206 and hose 210 may further include additional hoses, spray bars, shower systems, deck gun monitors or booms. Any number of discharge/spray apparatuses 206 and hoses 210 maybe employed on Electrolytic Decontamination System 200. Discharge/spray apparatus 206 and/or hose 210 may be in direct or indirect fluid communication with catholyte storage vessel 104, anolyte storage vessel 106, decontamination solution conditioning subsystem 102, and/or compressed air foam unit 204, for example. In one embodiment, discharge/spray apparatus 206 and hose 210 may apply decontamination solution 212 from catholyte storage vessel 104 onto substrate 214. In another embodiment, discharge/spray apparatus 206 and hose 210 may apply decontamination solution 212 from anolyte storage vessel 106 onto substrate 214. In yet another embodiment, discharge/spray apparatus 206 and hose 210 may apply decontamination solution 212 from compressed air foam unit 204 that contains a foaming agent for improved adherence of decontamination solution 212 to substrate 214 when it is in an orientation that is desirable to have such a foaming application. Additionally, although substrate 214 is shown in a horizontal orientation, the Electrolytic Decontamination System works with decontamination solution 212 in any orientation, such as inclined or vertical, for example. FIG. 3 illustrates a perspective view of Electrolytic Decontamination System 200.
FIG. 4 illustrates an embodiment of a perspective cutaway view of a decontamination solution conditioning subsystem 400. Decontamination solution conditioning subsystem 400 may include a pumping station 404 that pumps decontamination solution from fluid source 132, reverse osmosis/filtration unit 128, and/or fluid supply vessel 114, for example. The decontamination solution is preferably filtered at the filtering unit 420 on its way to a pumping station 404. Filtering unit 420 removes any large pieces of debris from the decontamination solution to prevent damage to an ionization unit 408. Additionally, any adjustments to the decontamination solution can be conducted at this point if necessary. These adjustments may be in the form of mineral addition (or removal) from the decontamination solution. Additionally, materials such as nano-particles, specific polymers or other materials may be added to enhance the ability of the carrier fluid to be ionized or carry a charge, or to enhance the ability to effect the sequesteration and/or decontamination of contaminants disposed on a substrate. Pumping station 404 then pumps the carrier fluid to the ionization unit 408 via a conduit or pipe 406. The ionization unit 408 may include a reduced decontamination solution outlet 416 and an oxidized decontamination solution outlet 418. Reduced decontamination solution outlet 416, oxidized decontamination solution outlet 418, or both, may then be either provided directly to catholyte storage vessel 104 and/or anolyte storage vessel 106 to be applied later to substrate 214. As described in more detail below, the ionization unit 408 contains a plurality of electrode plates 602 (FIG. 6) that are connected to a power supply, conditioning, and network control interface unit 414 via voltage lines 410 and 412. Electrode plates 602 may be made from any material that fits a designed application, such as titanium, graphite, platinum, stainless steel, iridium and the like.
FIG. 5 illustrates an embodiment of a decontamination solution conditioning subsystem 500 and FIG. 6 illustrates an embodiment 600 of an enlarged view of portion “A” of decontamination solution conditioning subsystem 500 of FIG. 5. Decontamination solution conditioning subsystem 500 includes an insulated housing 504 that forms an interior compartment 502 where decontamination solution is distributed from the pipe 406. After flowing through the pumping station 404, the decontamination solution enters decontamination solution conditioning subsystem 500 where the decontamination solution is ionized and separated into phases. The ionization process uses a plurality or series of pairs of simple electrode plates 602, each pair separated by a permeable membrane 702 (FIG. 7) that is typically made of various chloro-fluoro carbons. Membranes may be made of a wide range of materials including materials as simple as cotton fibers or any other appropriate material. Each pair consists of an anode electrode 604 and a cathode electrode 606. The decontamination solution flows through the electrode plates 602 and is ionized by the charges on the electrode plates 602 and then separated by the permeable membrane 702.
FIG. 7 illustrates the electrolytic process that ionizes the decontamination solution of the present Electrolytic Decontamination System. The generation of an ionized decontamination solution is produced by ionizing the decontamination solution in the ionization unit 408. As stated above, the ionization unit 408 typically consists of an insulated housing 504 with a plurality or series of pairs of electrode plates 602, such as anode electrode 604 and cathode electrode 606. Although in some designs a conducting material is used for the housing and then doubles as the electrodes. These two charged electrode plates 604 and 606, in this embodiment, are separated by a permeable membrane 702. An electrical potential is applied to the anode electrode 604 and cathode electrode 606 via voltage lines 410 and 412 while a carrier fluid flows through the ionization unit 408. Passageways 704 and 706 are created on each side of the permeable membrane 702 and each electrode plate 604 and 606, respectively. The carrier fluid acts as the conducting medium between the anode electrode 604 and cathode electrode 606. The charge across the two electrode plates 604 and 606 causes anions to be attracted to anode electrode 604 and cations to be attracted to the cathode electrode 606. Thus, the ionized decontamination solution is oxidized at the anode electrode 604 and the ionized decontamination solution is reduced at the cathode electrode 606. The ionized decontamination solution 710 in channel 704 is oxidized and the ionized decontamination solution 712 in channel 706 is reduced. A basic ionizer may also be constructed by using simple containers (like tanks) with an electrode in each container and linked with a pipe separated by a membrane. In this “batch” approach a flowing fluid may not be necessary. Some of the variables that control the magnitude of the electrolytic process are the flow rate of the decontamination solution through the insulated housing 504, the charge potential between the two electrode plates 604 and 606, the decontamination solution residence time, and the amperage used to ionize the decontamination solution. Ionization technology is currently in use to produce alkalized water for human consumption and acidic water for disinfectant applications. As is described further below, each application of the present Electrolytic Decontamination System may have different magnitudes of the variable for the most efficient use of the ionized decontamination solution. This will be defined by the decontamination objectives and the field parameters.
The ionized decontamination solution discharged from the insulated housing 504 through all of the channels 706 collectively of all of the pairs of the plurality of electrode plates 602 is separated into one stream that flows out the oxidized decontamination solution outlet 418. All of the channels 708 collectively of all of the pairs of the plurality of electrode plates 602 are separated into another stream that flows out reduced decontamination solution outlet 416. These two streams have a charge difference related to the dissolved constitutions in the decontamination solution, current density across the anode electrode 604 and cathode electrode 606, residence time in the ionization unit 408, and other secondary factors. The residence time in the presence of a charge allows the decontamination solution and its dissolved solids to disassociate and the anions and cations to pass through the permeable membrane 702, thus separating the dissolved solids. The size, power requirements, and detailed configuration of the ionization unit 408 and permeable membrane 702 (including membrane type) are dictated by the field specific requirements/applications.
In a preferred embodiment of an ionization apparatus, the membranes are typically stationary and placed closer to one plate or the other. This produces differing quantities of the effluent types (reducing or oxidizing), enabling the production of an increased amount of one type of effluent or the other (oxidizing or reducing). With this configuration, the charge on the plates can also be reversed to increase production of one effluent type over the other. This would produce the reversed quantity of produced effluent types. Additionally, the reversal of plate polarity is often used to clean the plates of scale or other materials.
Alternatively, the permeable membrane 702 could potentially be moveable between each pair or plurality of electrode plates 602. Thus, the permeable membrane 702 can be located closer to one electrode than the other electrode to create a larger volume of one species of ionized decontamination solution. For example, the permeable membrane 702 could be located closer to the anode electrode 604, thereby creating a greater volume of ionized decontamination solution 712 to be created. The membrane can be moved closer to one electrode to produce one species of ionized carrier fluid, such as ionized decontamination solution 710, and then later moved closer to the other electrode to produce another species of ionized decontamination solution, such as ionized decontamination solution 712.
Other configurations of an ionization apparatus could include systems using simple electrolysis with or without a membrane (e.g., ported systems or other configurations), variations in plate materials/configurations, such as tubes, meshes or blades in place of standard electrode plates, or any other embodiment that is able to produce an ionized decontamination solution adequate to generate beneficial results during the decontamination process. In one embodiment, the ionization unit 408 comprises one or more pairs of electrode plates 602 without a membrane interspersed between each of the one or more pairs of electrodes. In this embodiment, the housing 504 contains these electrode plates 602 and has an outlet located proximal to each electrode of each of the pairs of electrode plates 602 to remove the ionized decontamination solution prior to the ions being substantially deposited onto the electrodes.
The ionization of a decontamination solution that is saline (or other fluid with appropriate Total Dissolved Solids or TDS) changes the fluid ionic composition on both sides of the membrane 702. For example, as the decontamination solution passes through the ionization unit 408, it undergoes a partial disassociation of both the water (HOH) component and salt (NaCl) component of the decontamination solution, with ions migrating through the permeable membrane 702 to the opposite charged side where re-association will occur. For example, on one side of the membrane, sodium ions (Na⁺) and hydroxyl ions (OH⁻) will re-associate to form sodium hydroxide, NaOH, commonly known as the “alkaline” side. On the opposite charged side, hydrogen ions (H⁺) will re-associate with chlorine (Cl⁻) and form hydrochloric acid, or more typically hypochlorous acid, and is often known as the “acidic” or astringent side. Other compounds or combinations of compounds are used to attain the same goals using this approach. Most types of ionization units 408 will be able to produce this effect, although ionization units 408 that have chemical tolerant plates/membranes, possess easy to adjust controls, and are energy efficient are preferable.
The ionized decontamination solution, whether reduced or oxidized, is then provided to the the appropriate catholyte storage vessel 104 and anolyte storage vessel 106 or directly provided to compressed air foam unit 204, hose 210, and/or discharge/spray apparatus 206, for example. The oxidizing ionized decontamination solution may be used for enhancing the porosity of sub-surface formations or establishing a base electrochemical potential prior to releasing the contaminants on a substrate, among other applications. The alkaline ionizing decontamination solution can be used, with or without the oxidizing precursor, to release contaminants, for example. As noted above, catholyte storage vessel 104 and anolyte storage vessel 106 may be used to store one or the other of the ionized decontamination solution while the other is applied to substrate 214 via hose 210 and/or discharge/spray apparatus 206.
FIG. 8 illustrates a power supply conditioning and network control interface unit 414 of decontamination solution conditioning subsystem 102. The voltage lines 410 and 412 are shown protruding out of the side of the power supply conditioning and network control interface unit 414. Also, in one aspect, the power supply conditioning and network control interface unit 414 may include a control access door 804 for protecting the controls from the elements and the environment. A main disconnect 802 is also shown for quickly disconnecting the main power supply from the power supply conditioning and network control interface unit 414. FIG. 9 illustrates the power supply conditioning and network control interface unit 414, with the internal elements exposed for clarity. In particular, the power supply conditioning and network control interface unit 414 includes a main control interface 906 for supplying power to the voltage lines 410 and 412. In addition, the power supply conditioning and network control interface unit 414 preferably but not necessarily includes a network server 908 and a central processing unit 910 for further controlling the voltage supply to the voltage lines 410 and 412. Further, the power supply conditioning and network control interface unit 414 preferably includes a voltage rectification and conditioning element 914 for rectifying the voltage prior to its output through the voltage lines 410 and 412. Also, the power supply conditioning and network control interface unit 414 includes an integrated decontamination solution pump frequency drive controller 912 for controlling the pumping station 404. The power supply conditioning and network control interface unit 414 maintains the necessary settings for the ionized decontamination solution to maximize its effectiveness. A control panel 902 includes controls that may be manually operated or operated by a computing system located within the power supply conditioning and network control interface unit 414 or remotely via a network (not shown). The control panel 902 consists of a power control knob 904 and a polarity reversal switch 916. The power control knob 904 allows for adjustments to the voltage applied to the plurality of electrode plates 602, and thus controls the redox potential of the effluent decontamination solution. This control is known as the “dial-a-yield”, and allows adjustment to best suit the potential that is needed to most efficiently decontaminate a substrate. The polarity reversal switch 916 provides for cleaning of the plurality of electrode plates 602 by reversing the polarity, and to maximize the type of decontamination solution produced for a given application. In another aspect of the present Electrolytic Decontamination System, the polarity may be switched or reversed to produce a different species of ionized decontamination solution in a particular channel 706 and 708.
Both ionized materials will also have a significant “shift” in their respective redox potential from the initial state of the decontamination solution as the decontamination solution is adjusted to a different ionic state. The alkaline side will have a dramatic increase in excess electrons and become a powerful reducing agent. The opposite is true for the acidic side, which is deficient in electrons and is thus a powerful oxidizer. These shifts in redox potential can be well in excess of + or − 5000 mV as measured by eH. This limit can be as high as where the decontamination solution completely disassociates and will not carry any additional charge, or is no longer useful to the process. Alternatively, any measurable change in redox may be sufficient to produce desirable results. This measurement can be made by a simple pH/eH meter or more sophisticated data logging can be achieved by using a continuous flow through design, such as with inline pH/eH analyzers. Combinations of changing redox, pH, and the addition of select ions to modify the ionic state of the decontamination solution prior to injection into injection wells 106 allows for a controlled and selective extraction of economically valuable minerals and fluids.
The charge introduced by the decontamination solution creates a transient into the existing electrochemical potential field existing between a contaminant and a substrate. This transient is sustained by the continuous injection of electrons in the decontamination solution. Direct grounding (dissipation of electrons) may be accomplished via the substrate, for example. Thus, changes in the electrical state of the substrate may act as ground for excess electrons.
The change in redox potential dissipates by various physical responses on the substrate, for example. One such response is at the solid-liquid interface, where electron shifts are controlled by the ζ-potential. The ζ-potential acts from the solid to the liquid interface with a width on the order of a few molecular dimensions from the interface, and controls the release or decontamination of a liquid or solid bound to the solid-liquid interface by essentially an electrostatic charge. A multi-phase liquid in contact with a porous media, the ζ-potential at the solid-liquid interface has a substantial effect on the preferred substrate-contaminant wettability state. The ζ-potential is the interface where charge differences between the solid and liquid are accommodated.
Addition of surfactants, sequestering agents, nano-particles, tacking materials and other compounds to support the various mechanisms required for successful decontamination can be readily accomplished. The deployment of the decontamination solution may also be enhanced by the addition of foaming surfactants. These enhancements include expansion of the foam solution, providing a greater area of coverage per liquid volume, durability and insulation properties of foam keeping the decontamination solutions wet against the surface for required dwell times, resulting in enhanced contaminant removal, the foam's ability to adhere to vertical and inverted surfaces and the visual aspects of foam to assist as a visual marker for application coverage.
The ability to store materials in a dry or other highly concentrated state until deployed for application significantly reduces the logistical burden, minimizes storage requirements and nearly eliminates shelf life issues. The flexibility of the generation system allows for easy adjustment for field operations and changing conditions. One of the biggest attributes of this approach is the dramatic cost savings over many of the currently available technologies. By generating decontamination solutions On-Demand, the cost per volume generated is kept to a minimum.
Referring to FIG. 10, an embodiment of a recovery unit 1000 is shown. Recovery unit 1000 may include a housing 1002 and an inlet 1004 that feeds recovered contaminated fluid 1018 from a substrate 1016, for example. Contaminated fluid 1018 may be recovered from substrate 1016 by any number of mechanical means, including use of a vacuum unit 1006, for example. Vacuum unit 1006 may apply a negative pressure near or proximal to substrate 1016 to cause contaminated fluid 1018 to be removed from substrate 1016. Removal of spent decontamination solution from substrates contaminated with radiological materials may be commonly completed by vacuum systems. This approach assists in the removal of spent decontamination solution (and contaminants) from the substrate pores and surfaces. Vacuum systems are available in a wide variety of sizes and configurations, making the overall systems scalable and tailor-able for the specific application. The use of vacuum systems also minimizes exposure during waste handling activities and may expedite the processing of most types of collected contaminants. Commercially available vacuum systems are available (in sizes from hand held and man portable systems to large truck, trailer or skid mounted units) and can be modified to include rinsate dispensers, HEPA filters and suction manifolds to support multiple suction hoses and appliances in order to address the specific situations and makeup of the contamination being collected for treatment and/or disposal.
Another key aspect of a radiological recovery operation is the handling and disposal of waste, particularly liquid waste generated during the recovery operation. For example, contaminated fluid 1018 may be fed through inlet 1004 into housing 1002 that may contain rechargeable capture media 1010 for capturing a particular contaminant, such as radioactive particles 1008. Rechargeable capture media 1010 capture contaminated fluid 1018 allowing the decontamination solution to exit housing 1002 through an outlet 1014. The Electrolytic Decontamination System described herein may also be utilized to generate eletrolytically charged fluids in order to create the rechargeable capture media 1010 that can be used to assist in fluid waste processing. The control of the media/device would be through the adjustment of the reductive/oxidative potential of the media to either capture or reversibly release materials of interest. This device has applications in waste handling, resource recovery, media separation and/or media containment.
Any media that is responsive to being acted upon via electrolytic fluids may be utilized for this purpose and may include a wide range of substances. These materials may include silicates, clays, coal (or other active carbon), polymers or a wide range of similar materials. Most any manmade or natural occurring substance that can be modified at the material surface by using a charged fluid that affects the zeta potential can be effectively utilized.
In one example of an electrolytic capture media/device, housing 1002 is packed with basic geologic media such as sand (silicate), coal and clay. A charged fluid generated by the Electrolytic Decontamination System is then passed through the tube (in this example a reductive fluid) and the media takes on the characteristics (charge) of the electrolytically altered fluid. For example, a fluid with −800 mv of reductive charge can be passed through the media until the media contained in the tube also exhibits a charge of the same or near the same reductive potential, with the corresponding surplus of electrons. The charged media is now ready for use.
In this example, the contaminated fluids recovered during the recovery operations, in this case mildly oxidized fluids containing isotopic contaminants or radioactive particles 1008 (soluble in the oxidizing fluids) are passed through the housing 1002 containing the charged media. The reductive potential of the media alters the incoming oxidizing fluid containing the contaminants and causes it to become reducing, and therefore insoluble, and the contaminants of interest drop out of the fluid and become bonded to the charged media, thus capturing the contaminants within the housing 1002. This allows for the removal of the components of interest while the “cleaned” fluid passes through the outlet 1014. The process can then be reversed bypassing an oxidizing fluid through the media in order to re-solubilize the contaminants for controlled removal as a concentrate or for disposal.
Additionally, when the decontamination solution contains several contaminant compounds, but where only one or two are of interest, the charged media can be easily modified or adjusted so that the reduction/oxidation effects are specifically tailored to extract one or more compounds of interest, depending on the strength of the electrostatic bonds which are specific to each compound, while leaving the other non-targeted contaminants in place. It should be noted that the process may be entirely reversed (an oxidizing charge of the media followed by a reductive fluid containing the compound of interest) depending on the application. Also, it is important to note that the terms oxidizing and reducing are relative terms and the opposite fluid may actually be near neutral as measured. This approach is applicable to any contaminant or compound of interest where solubility can be affected through the varying of oxidation/reduction reactions.
While the preceding discussion describes the use of the capture media/device for removal of isotopic contamination from fluids in the event of an RDD recovery, numerous additional applications exist for this device. These include, but are not limited to, removal of heavy metal contaminants from acid mine drainage, removal of minerals of interest from solution mining operations, and anywhere else that substances can be captured or released by preferential modification of charge, directly affecting zeta potential.
An example of Industrial cleaning or decontamination is the use of the Electrolytic Decontamination System to generate various oxidative/reductive solutions to be used in conjunction with selected surfactant materials for the de-scaling and de-greasing of turbine blades in the electrical power generation industry. Periodically, turbine blades must be cleaned of scale in order to restore operating efficiencies. Many existing chemical based de-scaling solutions include the logistical and cost problems described above for RN decontamination formulas, and also include aspects of materials compatibility on these high-value metallic components. The formulas generated by the present Electrolytic Decontamination System solve most of these problems while being environmentally and materially benign, providing enhanced cleaning at a fraction of the cost of legacy solutions. This advantage is from the charge potential that is embarked into the fluid as opposed to traditional chemicals that rely on molar mass for effectiveness.
The Electrolytic Decontamination System may also be used for industrial radiological decontamination in nuclear power plants, on Naturally Occurring Radioactive Material (NORM) de-scaling, fuel processing or nuclear weapons complex applications and the like. For industrial applications, the formulations and procedures may be efficiently optimized for specific operations and environments.
For example, industrial radiological contaminants may have been in place for decades, covered with grease, dirt or other constituents that have clogged substrate pores, making the removal of contaminants more difficult. These materials must be removed prior to or in conjunction with the radiological contamination removal. In this case, a combined oxidative solution of hypochlorous and nitric acids, or other generated acids, may be used to oxidize the surface grease and grime and thus prepare the substrate by removing these constituents and opening the surface pores to ready them for radiological decontamination operations. Various surfactants and chelating agents may also be added to the solution as described above.
In this example, such materials could be generated using an electrolytic process from stable salts such as sodium chloride, potassium chloride, potassium nitrate, and/or sodium nitrate. As described above, the addition of wetting agents, surfactants and the like may be used to enhance the effectiveness of the removal or cleaning process prior to radiological and/or industrial decontamination operations.
Another example of tailoring decontamination solution for industrial or other use is the addition of neutron poisons to reduce the risk of a criticality event when removing fissile nuclear materials. This is commonly completed with the addition of neutron absorbing materials like boron or similar materials, as criticality is a major safety concern when working with fissile isotopes.
In this example, a sodium tetra-borate deca-hydrate (STBDH) material could be used as a neutron poison (or any other suitable material in the alkaline portion of the decontamination solution. Boric acid may also be added to the acidic portion of the electrolysis cell and can then be used in conjunction with the other components of the decontamination process. Note that this is just one set of examples, and the actual removal processes may be altered, repeated or even reversed depending on the substrates, constituents and contaminants.
Further, the present Electrolytic Decontamination System controls the electrochemical state of the substrate without the introduction of expensive or complex chemicals, and thus reduces overall costs and logistical requirements. This allows the contaminants to be extracted and processed at a lower cost than conventional methods, significantly advancing the state-of-the-art.
Electrochemical Potentials
FIG. 11 illustrates a ζ-potential at a solid-liquid interface, solid-solid interface, liquid-liquid interface, contaminant-substrate interface, and the hypothetical charge distribution. The charged layers at the solid-liquid interface, for example, behave as two parallel surfaces of opposite electrical charge separated by a distance of molecular dimensions. A layer of one charge on the solid particle surface and a layer of opposite charge in the layer of fluid directly adjacent to the solid surface (Stem Layer) has a potential difference called the ζ-potential. The outer region where a balance of electrostatic forces and random thermal motion determines the ion distribution is known as the diffuse layer. The ζ-potential acts on the solid-liquid interface on the substrate, satisfying electrochemical potentials that increase the water wettability of the substrate, for example. If electrical forces displace or change the charge, fluid can either be released or entrapped from the solid-liquid interface. In an oleic-water system, a reducing environment (addition of electrons) increases water wettability, reducing the ζ-potential at the solid-liquid interface, releasing the deposited contaminants.
The present Electrolytic Decontamination System acts upon the charge balance without the introduction of external chemicals or extraneous substances. By introducing an ionized decontamination solution to the contaminant-substrate interface, the charge on the decontamination solution disrupts the contaminant-substrate interface, thus allowing the contaminant, such as radioactive particles, to not be attracted to (be repelled by) the charge of the substrate. In addition, in one embodiment, the decontamination solution is comprised of water, which, due to its surface tension with the substrate, displaces the contaminant, such as radioactive particles, from the pores and surfaces of the substrate. The change in charge can be reversibly controlled by the introduction of an oppositely charged decontamination solution, thus directly changing the substrate wettability state and the ζ-potential. The charge can be reversed by introducing an oppositely charged decontamination solution into the system.
In addition to the aforementioned aspects included in and embodiments of the present Electrolytic Decontamination System, the present Electrolytic Decontamination System further includes methods for decontaminating substrates. FIG. 12 illustrates a flow diagram of an embodiment 1200 of one such process. In step 1202, a brine solution is provided to the decontamination solution conditioning subsystem 102. The brine solution is pumped or fed to the decontamination solution conditioning subsystem 102 from a storage tank or other storage system. Step 1202 may further include producing the brine solution from dry or liquid brine feedstocks, such as a salt or other compound, by metering or mixing the brine feedstock with a liquid or fluid. This step may further include further metering or mixing the brine solution with a liquid or fluid feedstock to produce a brine solution having a desired salt or compound content.
In step 1204, the brine solution may be filtered at the filtering unit 420 on its way to the pumping station 404. The filtering unit 420 removes any large pieces of debris from the carrier fluid to prevent damage to the ionization unit 408. Additionally, any adjustments to the brine solution may be conducted at this point if necessary. These adjustments may be in the form of mineral addition (or removal) from the carrier fluid. Additionally, materials such as nano-particles may be added to enhance the ability of the carrier fluid to be ionized or carry a charge.
In the preferred embodiment in step 1206, a charge is provided to the brine solution by flowing the brine solution between an anode electrode 604 and a cathode electrode 606 separated by a permeable membrane 702 to produce a decontamination solution. A desired charge is applied to the electrodes. As described above, the amount of charge placed on the decontamination solution is determined by the specific application, and include determinations such as the flow rate of the decontamination solution through the insulated housing 504, the charge potential between the two electrode plates 604 and 606, the decontamination solution residence time, and the amperage used to ionize the carrier fluid.
This Electrolytic Decontamination System also includes other configurations of an ionization apparatus that could include systems using simple electrolysis with or without a membrane (e.g., ported systems or other configuration), variations in plate materials/configurations or any other embodiment that is able to produce an ionized fluid adequate to generate beneficial results during the extraction process.
In step 1208, the ionized carrier fluid may be pumped or flowed to anolyte storage vessel 106 and/or catholyte storage vessel 104 depending on the application. In step 1210, the decontamination solution is supplied to a discharge/spray apparatus 206 or hose 210 for application of the decontamination solution to a contaminant on a substrate. In step 1212, the decontamination solution may be removed along with the contaminant from the substrate.
FIG. 13 illustrates a flow diagram of an embodiment 1300 of another process of the Electrolytic Decontamination System that may be utilized for RDD recovery operations. In step 1302, a contaminant disposed on substrates is “tacked” of the loose or “smearable” contaminants to the affected substrates in order to arrest the spread of isotopic contamination due to air movement. This step may further include applying one of the oxidizing fluids described herein with a soluble polymer or other additive that, when applied to contaminated substrates, may arrest the spread of loose contamination and act as a first step to “set” or standardize the electrostatic charge existing between “fixed” contaminants and substrates. The additive or polymer may include sequestering materials to effectively capture loose contaminants, and be impervious to precipitation in order to buy time in the decontamination process and arrest the spread of the contamination or the re-contamination of cleaned areas.
In step 1304, a neutralizing rinsate (reducing or less oxidizing) may be applied when ready to remove the polymer coating and the captured “loose” contaminants, leaving only the electrostatically bonded “fixed” contamination on the substrates, preparing the substrates for further cleaning and alleviating hazards from airborne contaminants. The use of an oxidizing fluid also assists in opening substrate pores (via oxidation) to allow for better penetration of subsequent decontamination fluids. Other additives to the oxidizing fluid may also be utilized to enhance decontamination efficacy, and may include various surfactants, chelating agents and/or sequestering agents.
In step 1306, a decontamination solution generated by the Electrolytic Decontamination System (typically reducing), and containing sufficient electrochemical potential to break the electrostatic bonds holding the contamination to the substrate, may then be applied. As an example, if an electrostatic bond holding a contaminant to a substrate is 400 mv, then an excess of potential is induced in the decontamination solution to release the contaminant. As a practicality, it is typically easier to produce a decontamination solution with a much higher potential than is needed to break the electrostatic bond as described above. Pre and/or post-injected additives may be included to reduce the surface tension of the fluid, sequester released contaminants, enhance and/or stabilize the charge carrying capacity or to induce a capillary rise effect to assist in the removal of contamination from subsurface voids and capillaries. A water source may be used with or without pretreatment (traditional water treatment such as Reverse Osmosis (RO), water softening etc.) or additional additives to generate an effective decontamination solution. In step 1308, the decontamination solution and contaminant are removed from the substrate.
FIG. 14 illustrates a flow diagram of an embodiment 1400 of another process of the Electrolytic Decontamination System. In step 1402, a brine solution is generated as described herein for a particular application. This step may include including an additive for improved charge holding capabilities. In step 1404, the brine solution is provided to decontamination solution conditioning subsystem 102 and charged with either an oxidative or reductive charge, thus producing a decontamination solution with an alkaline or acidic solution for decontaminating a contaminant on a particular substrate. In step 1406, additional additives, such as nano-particles, surfactants, sequestering agents, and the like may be added to the charged decontamination solution. In step 1408, the decontamination solution is then applied to the contaminant disposed on the substrate. This step may further include adding a polymer or foaming agent to the decontamination solution prior or subsequent to application on the contaminant on the substrate.
In step 1410, the decontamination solution is allowed to dwell or reside on the contaminant and substrate for a period of time depending on conditions. In step 1412, the decontamination solution and contaminant are rinsed from the substrate to decontaminate the substrate. This step may further include collecting the decontamination solution and recovered contamination in a vessel for later processing and/or separating. In step 1414, the contamination level may be evaluated to determine whether to repeat process or adjust decontamination solution to specific applications as needed.
It should be noted that the processes described above may be altered and even reversed depending on the specific contaminant(s) and affected substrates, and is provided herein for example purposes. These examples provide an indication of the flexibility of the Electrolytic Decontamination System, as it can produce solutions needed (oxidizing and/or reducing fluids or any variant thereof) for the processes described herein. The decontamination solution can be adjusted as needed to address the unique oxidation/reduction requirements for the successful decontamination of varying substrates and contaminants with or without specific additives.
There has herein been described a novel system and method for decontaminating a contaminant disposed on a substrate. It should be understood that the particular embodiments described within this specification are for purposes of example and should not be construed to limit the invention. Further, it is evident that those skilled in the art may now make numerous uses and modifications of the specific embodiment described, without departing from the inventive concepts. For example, the decontamination solution that is described can be any type of fluid useable for a desired application such as described herein. It is also evident that the process steps recited may in some instances be performed in a different order, or equivalent structures and processes may be substituted for the various structures and processes described The structures and processes may be combined with a wide variety of other structures and processes.

Claims

1. An electrolytic method for decontaminating a contaminant disposed on a substrate comprising:

providing a brine solution;

providing a pair of electrodes interposed by a permeable membrane to create a first channel and a second channel;

flowing the brine solution through the first and second channel;

applying a potential to the pair of electrodes to produce a first ionized decontamination solution in the first channel and a second ionized decontamination solution in the second channel;

applying one of the first ionized decontamination solution and the second decontamination solution to the contaminant; and

recovering the at least one of the first ionized decontamination solution and the second ionized decontamination solution and the contaminant from the substrate.

2. The electrolytic method for decontaminating a contaminant disposed on a substrate of claim 1 further comprising:

separating the contaminant from said at least one of said first ionized decontamination solution and said second ionized decontamination solution.

3. The electrolytic method for decontaminating a contaminant disposed on a substrate of claim 1, wherein the providing a brine solution further comprises:

mixing a brine feedstock with a supply of liquid.

4. The electrolytic method for decontaminating a contaminant disposed on a substrate of claim 3, wherein the brine feedstock is a salt.

5. The electrolytic method for decontaminating a contaminant disposed on a substrate of claim 1, further comprising:

foaming one of the first ionized decontamination solution and the second ionized decontamination solution during application to the substrate.

6. The electrolytic method for decontaminating a contaminant disposed on a substrate of claim 1, wherein the recovering the at least one of the first ionized decontamination solution and the second ionized decontamination solution further comprises:

flowing the recovered contaminant and the at least one of the first ionized decontamination solution and the second ionized decontamination solution through a recapture media having an opposite charge of the contaminant to capture the contaminant.

7. The electrolytic method for decontaminating a contaminant disposed on a substrate of claim 6, wherein the recapture media has a reductive charge.

8. The electrolytic method for decontaminating a contaminant disposed on a substrate of claim 1 further comprising:

adding to the decontamination solution at least one of the group consisting of surfactants, sequestering agents, nano-particles, and tacking materials.

9. The electrolytic method for decontaminating a contaminant disposed on a substrate of claim 1 further comprising:

tacking the decontamination solution on the substrate with an ionized decontamination solution.

10. The electrolytic method for decontaminating a contaminant disposed on a substrate of claim 1, wherein the applying a potential to the pair of electrodes further comprises:

adjusting said flowing of the decontamination solution to change the magnitude of charge on said first ionized decontamination solution and said second ionized decontamination solution.

11. The electrolytic method for decontaminating a contaminant disposed on a substrate of claim 1, wherein the applying a potential to the pair of electrodes further comprises:

adjusting the potential to change the magnitude of charge on the first ionized decontamination solution and the second ionized decontamination solution.

12. The electrolytic method for decontaminating a contaminant disposed on a substrate of claim 1, wherein the providing a pair of electrodes further comprises:

adjusting the location of the permeable membrane relative to the pair of electrodes to change the volume of the first ionized decontamination solution relative to the second ionized decontamination solution.

13. The electrolytic method for decontaminating a contaminant disposed on a substrate extracting components of claim 1 further comprising:

monitoring at least one of pH and eH of the first ionized decontamination solution and the second ionized decontamination solution.

14. The electrolytic method for decontaminating a contaminant disposed on a substrate of claim 1, wherein at least one of the first ionized decontamination solution and the second ionized decontamination solution has a negative reduction potential.

15. The electrolytic method for decontaminating a contaminant disposed on a substrate of claim 1, wherein at least one of the first ionized decontamination solution and the second ionized decontamination solution comprises a positive oxidation potential.

16. The electrolytic method for decontaminating a contaminant disposed on a substrate of claim 1 further comprising:

filtering the decontamination solution.

17. The electrolytic method for decontaminating a contaminant disposed on a substrate of claim 1 further comprising:

adjusting the mineral content of said decontamination solution.

18. The electrolytic method for decontaminating a contaminant disposed on a substrate of claim 17 wherein said adjusting comprises:

adding or removing a component of the group consisting of clay particulates and nano particles.

19. An electrolytic system for decontaminating a contaminant disposed on a substrate comprising:

means for providing a brine solution;

means for providing a pair of electrodes interposed by a permeable membrane to create a first channel and a second channel;

means for flowing the brine solution through the first and second channel;

means for applying a potential to the pair of electrodes to produce a first ionized decontamination solution in the first channel and a second ionized decontamination solution in the second channel;

means for applying one of the first ionized decontamination solution and the second decontamination solution to the contaminant; and

means for recovering the at least one of the first ionized decontamination solution and the second ionized decontamination solution and the contaminant from the substrate.

20. The electrolytic system for decontaminating a contaminant disposed on a substrate of claim 19 further comprising:

means for separating the contaminant from said at least one of said first ionized decontamination solution and said second ionized decontamination solution.

21. The electrolytic system for decontaminating a contaminant disposed on a substrate of claim 19, wherein the means for providing a brine solution further comprises:

means for mixing a brine feedstock with a supply of liquid.

22. The electrolytic system for decontaminating a contaminant disposed on a substrate of claim 21, wherein the brine feedstock is a salt.

23. The electrolytic system for decontaminating a contaminant disposed on a substrate of claim 19, further comprising:

means for foaming one of the first ionized decontamination solution and the second ionized decontamination solution during application to the substrate.

24. The electrolytic system for decontaminating a contaminant disposed on a substrate of claim 19, wherein the means for recovering the at least one of the first ionized decontamination solution and the second ionized decontamination solution further comprises:

means for flowing the recovered contaminant and the at least one of the first ionized decontamination solution and the second ionized decontamination solution through a recapture media having an opposite charge of the contaminant to capture the contaminant.

25. The electrolytic system for decontaminating a contaminant disposed on a substrate of claim 24, wherein the recapture media has a reductive charge.

26. The electrolytic system for decontaminating a contaminant disposed on a substrate of claim 19 further comprising:

means for adding to the decontamination solution at least one of the group consisting of surfactants, sequestering agents, nano-particles, and tacking materials.

27. The electrolytic system for decontaminating a contaminant disposed on a substrate of claim 19 further comprising:

means for tacking the decontamination solution on the substrate with an ionized decontamination solution.

28. The electrolytic system for decontaminating a contaminant disposed on a substrate of claim 19, wherein the means for applying a potential to the pair of electrodes further comprises:

means adjusting said flowing of the decontamination solution to change the magnitude of charge on said first ionized decontamination solution and said second ionized decontamination solution.

29. The electrolytic system for decontaminating a contaminant disposed on a substrate of claim 19, wherein the means for applying a potential to the pair of electrodes further comprises:

means for adjusting the potential to change the magnitude of charge on the first ionized decontamination solution and the second ionized decontamination solution.

30. The electrolytic system for decontaminating a contaminant disposed on a substrate of claim 19, wherein the means for providing a pair of electrodes further comprises:

means for adjusting the location of the permeable membrane relative to the pair of electrodes to change the volume of the first ionized decontamination solution relative to the second ionized decontamination solution.

31. The electrolytic system for decontaminating a contaminant disposed on a substrate extracting components of claim 1 further comprising:

means for monitoring at least one of pH and eH of the first ionized decontamination solution and the second ionized decontamination solution.

32. The electrolytic system for decontaminating a contaminant disposed on a substrate of claim 19, wherein at least one of the first ionized decontamination solution and the second ionized decontamination solution has a negative reduction potential.

33. The electrolytic system for decontaminating a contaminant disposed on a substrate of claim 19, wherein at least one of the first ionized decontamination solution and the second ionized decontamination solution comprises a positive oxidation potential.

34. The electrolytic system for decontaminating a contaminant disposed on a substrate of claim 19 further comprising:

means for filtering the decontamination solution.

35. The electrolytic system for decontaminating a contaminant disposed on a substrate of claim 19 further comprising:

means for adjusting the mineral content of said decontamination solution.

36. The electrolytic system for decontaminating a contaminant disposed on a substrate of claim 35 wherein said means for adjusting comprises:

means for adding or removing a component of the group consisting of clay particulates and nano particles.

37. A system for decontaminating a contaminant disposed on a substrate comprising:

a source of brine feedstock;

a decontamination solution conditioning subsystem comprising:

a pair of electrodes interposed by a permeable membrane to create a first channel and a second channel;

a source of electricity for applying a potential to the pair of electrodes to produce a first ionized decontamination solution in the first channel and a second ionized decontamination solution in the second channel;

an application unit for in fluid communication with the decontamination solution conditioning subsystem for applying one of the first ionized decontamination solution and the second ionized decontamination to the contaminant disposed on the substrate; and

a recovery unit for recovering the at least one of the first ionized decontamination solution and the second ionized decontamination solution and the contaminant from the substrate.

38. The system for decontaminating a contaminant disposed on a substrate of claim 37 further comprising:

a compressed air foam unit in fluid communication with the application unit for providing the decontamination solution in a foamed form to the substrate.

39. The system for decontaminating a contaminant disposed on a substrate of claim 37 further comprising:

a filtration unit in fluid communication with the source of brine feedstock for filtering a source liquid prior to mixing with the brine feedstock.

40. The system for decontaminating a contaminant disposed on a substrate of claim 37, wherein the recovery unit further comprises:

a vacuum unit for vacuuming at least one of the at least one first ionized decontamination solution, the second ionized decontamination solution, and the contaminant from the substrate.

41. The system for decontaminating a contaminant disposed on a substrate of claim 37 further comprising:

at least one first storage unit in communication with the source of brine feedstock for storing salt compounds.