FIBER WASH SYSTEM AND METHOD
A system and method for washing and separating fiber in the processing of grains in between the steps of fermentation and distillation is disclosed. Also disclosed is a method for producing a high protein feed.
1 . A system for a dry mill ethanol plant comprising:
a fermentation vessel coupled to a separating means for separating fiber from protein in fermented grain;
a first outlet coupled to the separating means for routing the protein to a distillation column;
a second outlet coupled to the separating means for routing the separated fiber to a solvent wash system;
a third outlet coupled to the solvent wash system for routing the fiber to a solvent recovery system; and
a fourth outlet coupled to the solvent recovery vessel for routing the fiber to a fiber recovery system.
2 . The system of claim 1 , further comprising a fifth outlet coupled to the solvent recovery system for routing the recovered solvent for reuse.
3 . The system of claim 2 , wherein the recovered solvent is routed to a tank for capturing ethanol.
4 . The system of claim 1 , further comprising a washing stream comprising ethanol, wherein the washing stream is coupled to the solvent wash system.
5 . The system of claim 1 , wherein the fiber recovery system comprises a fiber dryer coupled to a fiber storage vessel.
6 . The system of claim 1 , wherein the solvent wash system comprises one or more screens and means of separation connected in series with a counter current wash comprising ethanol.
7 . A system for a dry mill ethanol plant comprising:
a fermentation vessel coupled to a separating means for separating fiber from protein in fermented grain;
a first outlet coupled to the separating means for routing the protein to a distillation column;
a second outlet coupled to the separating means for routing the separated fiber to a solvent wash system;
a third outlet coupled to the solvent wash system for routing the fiber to a solvent recovery system; and
a fourth outlet coupled to the solvent wash system for routing the fiber to a cellulosic process.
8 . The system of claim 7 , wherein the solvent wash system comprises one or more screens and means of separation connected in series with a counter current wash comprising ethanol.
9 . The system of claim 7 , further comprising a washing stream comprising ethanol coupled to the solvent wash system.
10 . The system of claim 7 , wherein the cellulosic process is configured to apply one more of pH adjustment, heat, enzyme addition, and fermentation.
11 . A method of recovering fiber from a dry mill ethanol plant comprising:
i) processing fermented ground grain in a separating means for separating fiber from ground grain, the separating means being positioned between a fermentation vessel for fermenting the ground grain and a distillation column, and
ii) washing the separated fiber to obtain washed fiber.
12 . The method of claim 11 , further comprising the following steps after step i):
separating fiber from protein in the fermented ground grain; and
routing the protein to a distillation column and distilling a whole stillage therefrom.
13 . The method of claim 11 , further comprising the following steps:
centrifuging the whole stillage to produce thin stillage;
evaporating the thin stillage to produce a syrup;
routing the syrup to a protein dryer to produce a high protein feed; and
routing the high protein feed to a storage tank.
14 . The method of claim 11 , wherein the step of washing the separated fiber comprises applying a counter-current solvent stream comprising ethanol.
15 . The method of claim 11 , wherein the step of washing the separated fiber comprises:
moving the separated fiber through one or more screens; and
applying a counter-current solvent stream comprising ethanol through each of the screens.
16 . The method of claim 13 , wherein centrifuging the whole stillage further produces a solids cake, and
wherein the method further comprises the step of routing the solids cake to the protein dryer to produce the high protein feed.
17 . The method of claim 14 , further comprising:
removing the solvent from the washed fiber;
drying the washed fiber; and
storing the dried fiber.
18 . The method of claim 17 , wherein after removing the solvent, the solvent is routed for reuse in the dry mill ethanol plant.
19 . The method of claim 11 , further comprising subjecting the washed fiber to a cellulosic process.