Removal of Glycerin From Biodiesel Using An Electrostatic Process

Abstract

A vertical electrostatic coalescer comprises a first and second electrode surface and a horizontally disposed foraminous surface. The first electrode surface and horizontally disposed foraminous surface are at ground potential. The first and second electrode surfaces share the same planar orientation relative to the central longitudinal axis of the vessel. The unique arrangement of the vessel and opposing pairs of first and second electrode surfaces provides for a substantially uniform voltage field around a perimeter of the vessel and an effective voltage field for coalescence within a center of the vessel. A circular-shaped distributor pipe or a distributor housing serves to absorb momentum of the incoming emulsion stream and distribute the stream into an interior of the vessel.

1 - 16 . (canceled) 
     
     
         17 . An electrostatic coalescer for promoting glycerin coalescence in a biodiesel stream comprising:
 an elongated, closed, vertically disposed vessel having a fluid inlet located at a lower portion, a first fluid outlet located at a lower portion of said vessel and a second fluid outlet located at a top portion of said vessel;   at least one horizontally disposed first electrode surface located in an upper portion of said vessel, a portion of said first electrode surface being in communication with an interior surface of said vessel;   a plurality of horizontally disposed second electrode surfaces being connectable to each other and located substantially parallel to and a substantially equal distance above and below said first electrode surface,   a power supply external to said vessel and in communication with said second electrode surfaces;   whereby said first and second electrode surfaces establish effectively a voltage field around a perimeter portion of said vessel and in a center portion of said vessel, the voltage field serving to coalesce glycerin in the stream to augment separation thereof from the stream.   
     
     
         18 . An electrostatic coalescer according to  claim 17  further comprising a horizontally disposed foraminous surface located in a lower portion of said vessel and in communication with an interior surface of said vessel. 
     
     
         19 . An electrostatic coalescer according to  claim 17  further comprising at least one of said first electrode surfaces and said second electrode surfaces having a grid arrangement. 
     
     
         20 . An electrostatic coalescer according to  claim 17 , said second electrode surface comprising a plurality of rods oriented substantially parallel to one another, each rod having a first and second end, said first and second ends being a substantially equal distance from an opposing interior surface of said vessel. 
     
     
         21 . An electrostatic coalescer according to  claim 17  further comprising one or more connector passageways, said passageway being located on an interior surface of said first electrode surface and allowing for one or more connectors connectable to said second electrode surface to pass therethrough. 
     
     
         22 . An electrostatic coalescer according to  claim 17  wherein a voltage between each opposing pair of first and second electrode surfaces is in a range of 2 kV/inch to 8 kV/inch. 
     
     
         23 . An electrostatic coalescer according to  claim 17  further comprising a distributer housing, said distributor housing being connectable to said inlet and having an array of ports located at an upper portion of said distributor housing. 
     
     
         24 . An electrostatic coalescer according to  claim 17  further comprising a level control located in a lower portion of said vessel. 
     
     
         25 . An electrostatic coalescer for promoting glycerin coalescence in a biodiesel stream comprising:
 an elongated, closed, vertically disposed vessel having a fluid inlet located at a lower portion, a first fluid outlet located at a lower portion of said vessel and a second fluid outlet located at a top portion of said vessel;   a vertically disposed cylindrical-shaped first electrode surface located in an upper portion of said vessel and arranged about a central longitudinal axis of said vessel, a portion of said first electrode surface being in communication with an interior surface of said vessel;   a vertically disposed cylindrical-shaped second electrode surface located in an upper portion of said vessel and arranged about said first electrode surface with a circumferential space therebetween;   a power supply external to said vessel and being in communication with said second electrode surfaces;   whereby said first and second electrode surfaces establish effectively a voltage field around a perimeter portion of said vessel and in a center portion of said vessel, the voltage field serving to coalesce glycerin in the stream to augment separation thereof from the stream.   
     
     
         26 . An electrostatic coalescer according to  claim 25  further comprising a horizontally disposed foraminous surface located in a lower portion of said vessel and in communication with an interior surface of said vessel; 
     
     
         27 . An electrostatic coalescer according to  claim 25  wherein a portion of said first electrode surface comprises a hollow closed end body and a portion of said second electrode surface comprises a foraminous surface. 
     
     
         28 . An electrostatic coalescer according to  claim 25  further comprising a circular-shaped distributor conduit, said distributor conduit being in communication with said fluid inlet and having an array of ports. 
     
     
         29 . An electrostatic coalescer according to  claim 25  further comprising a level control located in a lower portion of said vessel.