Electric field-driven, magnetically-stabilized ferro-emulsion phase contactor

• US 4,941,959 A
• Filed: 11/27/1989
• Issued: 07/17/1990
• Est. Priority Date: 11/27/1989
• Status: Expired due to Fees

• Current Assignee: Martin Marietta Energy Systems, Inc. (Martin Marietta Corporation)
• Original Assignee: Martin Marietta Energy Systems, Inc. (Martin Marietta Corporation)
• Inventors: Scott, Timothy C.
• Primary Examiner(s): Tufariello, T. M.
• Application Number:
  US07/441,494
• Time in Patent Office: 232 Days
• Field of Search: 204/186, 204/302
• US Class Current: 204/557
• CPC Class Codes: B01D 11/0419 in combination with an electric or magnetic field or with vibrations
• CPC Class Codes: B01D 11/0426 Counter-current multistage extraction towers in a vertical or sloping position
• CPC Class Codes: B01D 17/06 Separation of liquids from each other by electricity
• CPC Class Codes: B03C 1/00 Magnetic separation
• CPC Class Codes: B03C 1/01 by addition of magnetic adjuvants

Abstract

Methods and systems for interfacial surface area contact between a dispersed phase liquid and a continuous phase liquid in counter-current flow for purposes such as solvent extraction. Initial droplets of a dispersed phase liquid material containing ferromagnetic particles functioning as a "packing" are introduced to a counter-current flow of the continuous phase. A high intensity pulsed electric field is applied so as to shatter the initial droplets into a ferromagnetic emulsion comprising many smaller daughter droplets having a greater combined total surface area than that of the initial droplets in contact with the continuous phase material. A magnetic field is applied to control the position of the ferromagnetic emulsion for enhanced coalescence of the daughter droplets into larger reformed droplets.

Claims

1. A method for solvent extraction comprising the steps of:

introducing initial droplets of a dispersed phase liquid material containing ferromagnetic particles to a counter-current flow of a continuous phase;

applying a high intensity pulsed electric field to the initial droplets so as to shatter the initial droplets into a ferromagnetic emulsion comprising many smaller daughter droplets in the continuous phase, the daughter droplets having a greater combined total surface area than that of the initial droplets;

applying a magnetic field to the ferromagnetic emulsion to control the position of the ferromagnetic emulsion within the continuous phase;

coalescing a plurality of the daughter droplets into larger reformed droplets; and

separating the reformed droplets from the continuous phase.

2. A method in accordance with claim 1, wherein said dispersed phase comprises aqueous droplets containing. ferromagnetic particles, and said continuous phase comprises an organic liquid.

3. A phase contactor, comprising:

a column for transporting a dispersed phase and a continuous phase in counter-current, said column including an emulsification and coalescence region and a dispersed phase collection region;

a source of dispersed phase liquid material containing ferromagnetic particles;

an element for introducing into said emulsification and coalescence region initial droplets of the dispersed phase liquid material to a counter-current of the continuous phase;

means for applying a high intensity pulsed electric field to the initial droplets in said emulsification and coalescence region so as to shatter the initial droplets into a ferromagnetic emulsion comprising many smaller daughter droplets having a greater combined total surface area than that of the initial droplets, the daughter droplets coalescing into larger reformed droplets which travel through the continuous phase to said dispersed phase collection region; and

means for applying a magnetic field to said emulsification and coalescence region to control the position of the ferromagnetic emulsion, whereby coalescence and phase separation are enhanced.

4. A phase contactor in accordance with claim 3, wherein said column transports a relatively lighter continuous phase organic liquid upwardly, and transports droplets of a relatively heavier dispersed phase aqueous liquid downwardly.

5. A phase contactor in accordance with claim 3, which comprises a system for solvent extraction.

6. A phase contactor system comprising:

a source of dispersed phase liquid material;

a source of continuous phase material;

a source of ferromagnetic particles;

a mixer having inputs connected to said dispersed phase liquid material source and to said ferromagnetic particle source for forming a mixture of dispersed phase liquid material and ferromagnetic particles;

a counter-current phase contactor including;

a column having an intermediate emulsification and coalescence region, a dispersed phase collection region located in one direction with respect to said emulsification and coalescence region, and a continuous phase collection region located in an opposite direction with respect to said emulsification and coalescence region,

means connected to said continuous phase material source for establishing a flow of continuous phase material through said intermediate emulsification and coalescence region to said continuous phase collection region,

means connected to said mixer for introducing into said emulsification and coalescence region initial droplets of the mixture,

means for applying a high intensity pulsed electric field to the initial droplets in said emulsification and coalescence region so as to shatter the initial droplets into a ferromagnetic emulsion comprising many smaller daughter droplets having a greater combined total surface area than that of the initial droplets, the daughter droplets coalescing into larger reformed droplets which travel through the continuous phase to said dispersed phase collection region, and

means for applying a magnetic field to said emulsification and coalescence region to control the position of the ferromagnetic emulsion, whereby coalescence and phase separation are enhanced; and

a separator connected to said dispersed phase collection region for separating ferromagnetic particles from dispersed phase liquid material.

7. A system in accordance with claim 6, wherein ferromagnetic particles are recycled and said source of ferromagnetic particles comprises an output of said separator.

8. A system in accordance with claim 6, wherein:

said continuous phase collection region is located within said column above said emulsification and coalescence region, and said source of continuous phase material supplies a relatively lighter organic liquid which flows upwardly through said emulsification and coalescence region to said continuous phase collection region; and

wherein

said dispersed phase collection region is located within said column below said emulsification and coalescence region, and said source of dispersed phase liquid material supplies a relatively heavier aqueous liquid whereby the reformed droplets travel downwardly to said dispersed phase collection region.