Systems and methods for unipolar separation of emulsions and other mixtures

Abstract

Embodiments discussed herein relate to systems and methods for separating two or more phases of an emulsion or other mixture. The methods include providing the mixture with a net and unipolar charge (e.g., such that adjacent droplets therein acquire net and unipolar charges), thereby enhancing coalescence of like-phase droplets therein and producing, or enhancing the production of, two or more consolidated phases; and collecting the two or more consolidated phases.

1 . A system for separating two or more phases of emulsion mixture, the system comprising:
 (a) a source of a net and unipolar charge to enhance coalescence of like-phase and like-charge droplets therein and producing, or to enhance the production of, two or more consolidated phases, wherein the charge densities of a first and a second coalescing like-phase and like-charge droplet are different such that Q a /r a >>Q b /r b , wherein Q a  is the charge of droplet a, Q b  is the charge of droplet b, r a  is the radius of droplet a, and r b  is the radius of droplet b; and   (b) a container or support for containing or supporting the emulsion mixture therein or thereupon.   
     
     
         2 . (canceled) 
     
     
         3 . The system of  claim 2 , wherein the source is or comprises an emitter electrode and the system comprises a collector electrode, wherein at least the collector electrode is in physical contact with the mixture and a potential difference is applied between the emitter electrode and the collector electrode at or above a corona discharge threshold. 
     
     
         4 . The system of  claim 3 , wherein the emitter electrode is not in physical contact with the mixture. 
     
     
         5 . The system of  claim 4 , wherein a gaseous medium is located between the emitter electrode and the mixture. 
     
     
         6 . The system of  claim 3 , wherein the collector electrode is grounded. 
     
     
         7 . The system of  claim 3 , wherein the emitter electrode is a sharp electrode. 
     
     
         8 . The system of  claim 3 , wherein the emitter electrode is coated and/or textured. 
     
     
         9 . The system of  claim 3 , wherein the emitter electrode is made of or coated with a material resistant to ionization-induced corrosion. 
     
     
         10 . The system of  claim 3 , wherein the collector electrode comprises one or more members selected from the group consisting of a metal, silicon, and a silicon with native oxide, and/or wherein the collector electrode is coated with a dielectric film. 
     
     
         11 . The system of  claim 3 , wherein the potential difference between the emitter electrode and the mixture is established by applying a high voltage to the emitter electrode or by applying a high voltage to the mixture by reversing a polarity of the emitter electrode. 
     
     
         12 . The system of  claim 3 , wherein an electric field is applied via continuous AC or DC discharge or via pulsed discharge, wherein the discharge is a two-phase, three-phase, or multi-phase discharge and/or wherein the discharge is a direct discharge or a barrier discharge. 
     
     
         13 . (canceled) 
     
     
         14 . (canceled) 
     
     
         15 . (canceled) 
     
     
         16 . The system of  claim 1 , wherein the separating is carried out during transport of the mixture. 
     
     
         17 . The system of  claim 1  comprising a mixer to mix a charged portion of the mixture into the remaining portion of the mixture, thereby enhancing coalescence of like-phase droplets therein and producing, or enhancing the production of, two or more consolidated phases. 
     
     
         18 . The system of  claim 1 , wherein the source is or comprises a device for injecting, spraying, or otherwise introducing a substance having a net and unipolar charge into the mixture, thereby enhancing coalescence of like-phase droplets therein and producing, or enhancing the production of, the two or more consolidated phases. 
     
     
         19 . The system of  claim 1 , wherein the source is or comprises an injector for injecting an ionized gas having a net and unipolar charge into the mixture. 
     
     
         20 . (canceled) 
     
     
         21 . (canceled) 
     
     
         22 . The system of  claim 1 , wherein the source is or comprises a substrate having a net and unipolar charge that is positive or negative. 
     
     
         23 . (canceled) 
     
     
         24 . (canceled) 
     
     
         25 . The system of  claim 1 , wherein the mixture, while maintaining a net and unipolar charge, comprises a combination of species having positive and negative charges. 
     
     
         26 . The system of  claim 1 , wherein the source is or comprises a conduit, the conduit comprising a coating configured to improve tribo-electrification charging. 
     
     
         27 . The system of  claim 1 , wherein the source is or comprises an electrode, a device for injecting, spraying, or otherwise introducing a substance having a net and unipolar charge, and a substrate having a net and unipolar charge, and/or any combination thereof. 
     
     
         28 . The system of  claim 1 , wherein the mixture comprises a plurality of liquid phases and/or wherein the mixture comprises one or more members selected from the group consisting of particles, proteins, DNA, RNA, and cells, and/or wherein the mixture comprises a liquid with low electrical conductivity. 
     
     
         29 . (canceled) 
     
     
         30 . (canceled) 
     
     
         31 . The system of  claim 1 , wherein the mixture comprises an aqueous phase, and the aqueous phase has a salt content of at least about 0.5M. 
     
     
         32 . The system of  claim 1 , wherein, prior to introduction of the net and unipolar charge, the mixture comprises a phase of droplets having average droplet diameter less than or equal to about 1000 micrometers in diameter, and wherein the droplets coalesce after introduction of the net and unipolar charge. 
     
     
         33 . The system of  claim 1 , wherein the mixture is a two-phase emulsion comprising an aqueous phase and a non-aqueous phase, wherein the aqueous phase is less than or equal to 50 wt. % of the emulsion and/or wherein the non-aqueous phase is less than or equal to 50 wt. % of the emulsion. 
     
     
         34 . (canceled) 
     
     
         35 . The system of  claim 1 , wherein the mixture is a three-phase mixture. 
     
     
         36 . The system of  claim 1 , wherein the mixture comprises a liquid phase, a solid phase, and a gas phase. 
     
     
         37 . The system of  claim 1 , wherein the mixture is a bubble-in-oil mixture or a foam-in-oil mixture and/or wherein the mixture comprises an emulsifier. 
     
     
         38 . (canceled) 
     
     
         39 . The system of  claim 1 , wherein the mixture comprises at least one phase having a salt content of at least about 0.5M. 
     
     
         40 . (canceled) 
     
     
         41 . The system of  claim 1 , wherein the mixture comprises an oil, the oil having an electrical conductivity between about 10 −14  S/m (highly insulating) to about 10 −5  S/m (highly conducting). 
     
     
         42 . The system of  claim 1 , wherein the mixture has an electrical conductivity between about 10 −7  S/m to about 100 S/m. 
     
     
         43 . The system of  claim 5 , wherein the gaseous medium is flowing. 
     
     
         44 . (canceled) 
     
     
         45 . A system for separating two or more phases of an mixture, the system comprising:
 (a) a container or support for containing or supporting the mixture therein or thereupon, wherein the container or support is or comprises a grounded collector electrode, and wherein the container or support comprises a ramp, lip, edge, and/or other elevated portion;   (b) an emitter electrode not in physical contact with the mixture; and   (c) a power source configured to apply a potential difference between the emitter electrode and the collector electrode at or above a corona discharge threshold, wherein a gaseous medium is located between the emitter electrode and the mixture, and wherein the container or support is configured to permit passage of a first phase of the mixture therethrough and/or thereover while disallowing passage of at least a second phase of the mixture therethrough and/or thereover upon application of the potential difference between the emitter electrode and the collector electrode at or above the corona discharge threshold, thereby causing or promoting separation of two or more phases of the mixture.   
     
     
         46 . The system of  claim 45 , wherein the power source is a conventional power source. 
     
     
         47 . The system of  claim 45 , wherein the power source is an electrostatic generator. 
     
     
         48 . The system of  claim 45 , wherein the system comprises one or more members selected from the group consisting of a skimmer, a gravitation separator, and a centrifugal separator. 
     
     
         49 . The system of  claim 45 , wherein the emitter electrode and/or the collector electrode is bare. 
     
     
         50 . The system of  claim 45 , wherein the emitter electrode and/or the collector electrode is coated.