Microwave-enhanced biodiesel method and apparatus

Abstract

A method and a device for the production of biodiesel are disclosed. A suitable bio-feedstock may be exposed to microwave energy during a mixing process, a separation process, and a wash process. A synergistic effect of the microwave energy and centrifugal separation may be used in a continuous process for producing biodiesel. The biodiesel may be produced from the feedstock in a continuous flow path. The microwave energy may enhance the reaction of the feedstock and catalyst to provide a mixture of an ester and glycerin, and the microwave energy may enhance the separation of the ester and the glycerin in a centrifuge. Finally, the microwave energy may enhance the wash process of the ester in a centrifuge to purify the ester to produce a usable biodiesel.

1 . A biodiesel production device, comprising:
 a microwave device configured to provide microwave energy to a chamber thereof;   a reaction vessel positioned within the microwave chamber;   a first separation apparatus in communication with the reaction vessel and positioned within the chamber; and   at least one second mixing and separation apparatus in communication with the first separation apparatus and positioned within the chamber.   
     
     
         2 . The biodiesel production device of  claim 1 , wherein the reaction vessel includes static mixers. 
     
     
         3 . The biodiesel production device of  claim 1 , wherein the first separation apparatus comprises a first centrifuge configured for initial separation of an ester and glycerin. 
     
     
         4 . The biodiesel production device of  claim 3 , wherein the first centrifuge further comprises:
 a first outlet for a first, denser material and configured to remove the first, denser material from the chamber; and   a second outlet in communication with the second mixing and separation apparatus.   
     
     
         5 . The biodiesel production device of  claim 1 , wherein the at least one second mixing and separation apparatus is a second centrifuge comprising:
 an inlet in communication with an outlet of the first centrifuge;   an inlet for a washing agent;   a first outlet for a first, denser material and configured to remove the first, denser material from the second centrifuge and from the chamber; and   a second outlet.   
     
     
         6 . The biodiesel production device of  claim 1 , wherein the reaction vessel, the first separation apparatus, and the at least one second mixing and separation apparatus are substantially transparent to microwave energy. 
     
     
         7 . The biodiesel production device of  claim 1 , wherein the reaction vessel, the first separation apparatus, and the at least one second mixing and separation apparatus comprise at least one of a polymer, a plastic, a water-free ceramic, a quartz, a carbon fiber, and a glass. 
     
     
         8 . The biodiesel production device of  claim 1 , wherein the biodiesel production device weighs less than 200 pounds and occupies a volume of no more than about nine cubic feet. 
     
     
         9 . The biodiesel production device of  claim 1 , wherein the reaction vessel, the first separation apparatus, and the second mixing and separation apparatus are mutually configured in a continuous flow path therethrough. 
     
     
         10 . The biodiesel production device of  claim 9 , wherein the continuous flow path is configured to produce between about 1 gallon per hour to about 12 gallons per hour of biodiesel. 
     
     
         11 . The biodiesel production device of  claim 10 , wherein the continuous flow path is configured to accommodate an in-process inventory of between about one gallon and about five gallons. 
     
     
         12 . The biodiesel production device of  claim 1 , wherein the at least one second mixing and separation apparatus is a second centrifuge comprising:
 a housing;   a rotor disposed within the housing;   an annular region defined by an inner wall of the housing and an outer wall of the rotor, and in communication with a first and a second inlet; and   a chamber disposed within the rotor and configured to separate a first material from a second, denser material.   
     
     
         13 . The biodiesel production device of  claim 1 , wherein the at least one second mixing and separation apparatus comprises at least two mixing and separation apparatuses configured in a series. 
     
     
         14 . A method of producing biodiesel, comprising:
 mixing a feedstock and a catalyst while applying microwave energy thereto to form an ester and glycerin mixture;   centrifugally separating the ester and the glycerin while applying microwave energy thereto; and   centrifugally mixing the ester with a washing agent and centrifugally separating a washed ester from the washing agent while applying microwave energy thereto.   
     
     
         15 . The method of  claim 14 , wherein the mixing the feedstock and the catalyst comprises introducing the feedstock and the catalyst into a reaction loop. 
     
     
         16 . The method of  claim 14 , wherein providing a feedstock comprises providing at least one animal- or plant-based fat feedstock or oil feedstock. 
     
     
         17 . The method of  claim 16 , wherein providing at least one animal-based or plant-based fat feedstock or oil feedstock comprises providing an animal fat, animal oil, vegetable fat, vegetable oil, restaurant grease, household grease, waste industrial frying oil, or mixtures thereof. 
     
     
         18 . The method of  claim 14 , wherein mixing the ester and the washing agent is effected in an annular region between a spinning rotor and a stationary housing of a centrifuge. 
     
     
         19 . The method of  claim 18 , wherein separating from the washing agent is effected within the spinning rotor of the centrifuge. 
     
     
         20 . A method of producing biodiesel, comprising:
 mixing a feedstock and a catalyst within a reaction vessel while applying microwave energy thereto from a microwave generation device associated therewith to form an ester and glycerin mixture in the reaction vessel;   separating the ester and the glycerin in a first centrifuge while applying microwave energy thereto from a second microwave generation device associated therewith; and   washing the ester in a second centrifuge while applying microwave energy thereto from a third microwave generation device associated therewith.   
     
     
         21 . The method of  claim 20 , wherein separating the ester and the glycerin in a first centrifuge while applying microwave energy thereto comprises applying the microwave energy from the second microwave generation device positioned within an interior shaft of the first centrifuge. 
     
     
         22 . The method of  claim 21 , further comprising providing the second microwave generation device selected from the group consisting of a maser, a klystron, and a magnetron. 
     
     
         23 . The method of  claim 20 , wherein washing the ester comprises mixing the ester and the washing agent in an annular region between a spinning rotor and a stationary housing of a centrifuge. 
     
     
         24 . The method of  claim 23 , wherein washing the ester further comprises separating the ester from the washing agent within the spinning rotor of the centrifuge. 
     
     
         25 . A biodiesel production system, comprising:
 a reaction vessel having a first microwave device configured to provide microwave energy to the reaction vessel;   a first separation apparatus in communication with the reaction vessel and having a second microwave device configured to provide microwave energy thereto; and   a second mixing and separation apparatus in communication with the first separation apparatus and having a third microwave device configured to provide microwave energy thereto.   
     
     
         26 . The biodiesel production system of  claim 25 , wherein the second microwave device is positioned is positioned within an interior shaft of the first separation apparatus. 
     
     
         27 . The biodiesel production system of  claim 25 , wherein the third microwave device is positioned is positioned within an interior shaft of the second mixing and separation apparatus.