Continuous bioreactor and process

Claim 2

1- A process for continuously propagating microorganisms in a purified nutrient medium therefor, comprising the steps of: a) continuously flowing a liquid nutrient medium through the length of a cylindrical, spirally-wound membrane having a cylindrical outer surface and a cylindrical inner surface concentric therewith and which is separated from said outer surface by concentric layers of said spirally-wound membrane, said inner surface defining an interior cylindrical space throughout the length of said cylindrical spirally-wound membrane, whereby there is established a substantially radial flow of at least a portion of said nutrient medium through said spirally-wound membrane and into said interior cylindrical space, said radial flow of nutrient medium having removed therefrom, by said membrane, solids, including impurities, having a size above a predetermined value; b) establishing a continuous flow of microorganism through the hollow cylindrical interior of a tubular membrane material, said tubular membrane material being arranged within the interior cylindrical space of said spirally-wound membrane so as to be substantially concentric therewith, the pore size of said tubular membrane being such that said microorganism is confined within the hollow cylindrical interior thereof, and such that at least a portion of said radial flow of nutrient medium passes through said tubular membrane for contact with the microorganism in said hollow cylindrical interior, the nutrient medium passing through said tubular membrane having removed therefrom, by said membrane, solids, including impurities, having a size above a predetermined value; (c) maintaining conditions within said hollow cylindrical interior of said tubular membrane effective to propagate said microorganizm in said nutrient medium; and (d) continuously removing from said hollow cylindrical interior of said tubular membrane propagated microorganism and nutrient medium.

Claim 3

The process according to claim 1 wherein said tubular membrane material is arranged within the interior cylindrical space of said spirally-wound membrane so as to be spaced apart from the cylindrical inner surface of said spirally-wound membrane, whereby said inner surface of the spirally-wound membrane and the outer surface of said tubular membrane define an annular chamber.

Claim 4

The process according to claim 2 wherein a gaseous material is introduced into said annular chamber.

Claim 5

The process according to claim 3 wherein said microorganism requires aerobic conditions for propagation and wherein said gaseous material introduced into said annular chamber is an oxygen-containing gas.

Claim 6

The process according to claim 4 wherein said microorganism is yeast.

Claim 7

The process according to claim 5 wherein said nutrient medium comprises molasses.

Claim 8

The process according to any of claims 2 to 6 wherein the continuous flow of liquid nutrient medium through the length of said cylindrical spirally-wound membrane is countercurrent to the flow of microorganism through the hollow cylindrical interior of said tubular membrane.

Claim 9

The process according to any of claims 2 to 6 wherein the continous flow of liquid nutrient medium through the length of said cylindrical spirally-wound membrane is co-current to the flow of microorganism through the hollow cylindrical interior of said tubular membrane.

Claim 10

The process according to any of claims 2 to 8 wherein the spirally-wound ultrafiltration membrane is effective to remove from said nutrient medium solids having molecular weights greater than about 30,000 daltons.

Claim 11

The process according to claim 9 wherein said tubular membrane material has an average pore diameter of from about 0.2 to about 1.2 microns.

Claim 12

The process according to any of claims 2 to 8 wherein the spirally-wound ultrafiltration membrane is effective to remove from said nutrient medium solids having a molecular weight above about 15,000 daltons.

Claim 13

The process according to claim 11 wherein said tubular membrane material has an average pore diameter of from about 0.2 to 0.5 microns.

Claim 14

A process for continuously propagating yeast in a purified nutrient medium comprising molasses, comprising the steps of: a) continuously flowing a liquid nutrient medium . comprising molasses through the length of a cylindrical, spirally-wound membrane having a cylindricar outer surface and a cylindrical inner surface concentric therewith and which is separated from said outer surface by concentric layers of said spirally-wound membrane, said inner surface defining an interior cylindrical space throughout the length of said cylindrical spirally-wound membrane, whereby there is established a substantially radial flow of said nutrient medium into said interior cylindrical space, said radial flow of nutrient medium having removed therefrom solids having a molecular weight above about 30,000 daltons; b) establishing a continous flow of yeast through the hollow cylindrical interior of a tubular membrane material, said tubular membrane material being arranged within the interior cylindrical space of said spirally-wound membrane so as to be substantially concentric therewith and such that the inner surface of the spirally-wound membrane and the outer surface of said tubular membrane are spaced apart and define an annular chamber, whereby at least a portion of the nutrient medium obtained from said spirally-wound membrane passes through the outer surface of said tubular membrane for contact with the microorganism within the hollow cylindrical interior of said tubular membrane, said tubular membrane having an average pore diameter of from about 0.2 to 1.2 microns; c) flowing an oxygen-containing gas either through said annular chamber for mixing with nutrient medium from said spirally-wound membrane and/or through the hollow cylindrical interior of said tubular membrane; d) maintaining conditions within said hollow cylindrical interior of said tubular membrane effective to propagate said yeast in said nutrient medium therein; and e) continuously removing from said hollow cylindrical interior of said tubular membrane propagated yeast and nutrient medium.

Claim 15

A process for continuously propagating yeast in a purified nutrient medium comprising molasses, comprising the steps of: a) continuously flowing a liquid nutrient medium . comprising molasses through the length of a cylindrical, spirally-wound membrane having a cylindricar outer surface and a cylindrical inner surface concentric therewith and which is separated from said outer surface by concentric layers of said spirally-wound membrane, said inner surface defining an interior cylindrical space throughout the length of said cylindrical spirally-wound membrane, whereby there is established a substantially radial flow of said nutrient medium into said interior cylindrical space, said radial flow of nutrient medium having removed therefrom solids having a molecular weight above about 30,000 daltons; b) establishing a continous flow of yeast through the hollow cylindrical interior of a tubular membrane material, said tubular membrane material being arranged within the interior cylindrical space of said spirally-wound membrane so as to be substantially concentric therewith and such that the inner surface of the spirally-wound membrane and the outer surface of said tubular membrane are spaced apart and define an annular chamber, whereby at least a portion of the nutrient medium obtained from said spirally-wound membrane passes through the outer surface of said tubular membrane for contact with the microorganism within the hollow cylindrical interior of said tubular membrane, said tubular membrane having an average pore diameter of from about 0.2 to 1.2 microns; c) flowing an oxygen-containing gas either through said annular chamber for mixing with nutrient medium from said spirally-wound membrane and/or through the hollow cylindrical interior of said tubular membrane; d) maintaining conditions within said hollow cylindrical interior of said tubular membrane effective to propagate said yeast in said nutrient medium therein; and e) continuously removing from said hollow cylindrical interior of said tubular membrane propagated yeast and nutrient medium.

Claim 16

The process according to Claim 13 wherein said spirally- wound ultrafiltration membrane and said tubular membrane are effective to reduce the microorganism count of said nutrient medium within the hollow cylindrical interior of said tubular membrane to less than about 10 microorganisms per 100 grams of nutrient medium-

Claim 17

The process according to Claim 14 wherein the flow of said nutrient medium through the length of said spirally-wound ultrafiltration membrane and the flow of oxygen-containing gas into said annular chamber are countercurrent to the flow of yeast in the hollow cylindrical interior of said tubular membrane.

Claim 18

The process according to Claim 13 wherein said oxygen-containing gas contains at least about 50% oxygen on a volume basis.

Claim 19

A process for continuously propagating microorganisms in a purified nutrient medium therefor, comprising the steps of: a) continuously flowing a liquid nutrient medium. through the length of a cylindrical spirally-wound ultrafiltration membrane having a cylindrical outer surface and a cylindrical inner surface concentric therewith and which is separated from said outer surface by concentric layers of said spirally-wound membrane, said inner surface defining an interior cylindrical space throughout the length of said spirally-wound membrane, whereby there is established a substantially radial flow of at least a portion of said nutrient medium through said spirally-wound membrane and into said interior cylindrical space, said radial flow of nutrient medium having removed therefrom, by said spirally-wound membrane, solids having a molecular weight above about 30,000 daltons; b) continuously removing nutrient medium from said interior cylindrical space; c) continuously passing said removed nutrient medium of (b) along the cylindrical outer surface of a tubular membrane material, said membrane material having an average pore diameter of from about 0.2 to 1.2 microns, whereby at least a portion of said nutrient medium passes through said tubular membrane material into the hollow cylindrical interior thereof; d) continuously introducing microorganisms into said hollow cylindrical interior of said tubular membrane material for contact with nutrient medium therein; e) maintaining in said hollow cylindrical interior of said tubular membrane material conditions effective to propagate said microorganism in said nutrient medium; and f) continuously removing from said hollow cylindrical interior propagated microorganisms and nutrient medium.

Claim 20

A process for continuously propagating microorganisms in a purified nutrient medium therefor, comprising the steps of: a) continuously flowing a liquid nutrient medium. through the length of a cylindrical spirally-wound ultrafiltration membrane having a cylindrical outer surface and a cylindrical inner surface concentric therewith and which is separated from said outer surface by concentric layers of said spirally-wound membrane, said inner surface defining an interior cylindrical space throughout the length of said spirally-wound membrane, whereby there is established a substantially radial flow of at least a portion of said nutrient medium through said spirally-wound membrane and into said interior cylindrical space, said radial flow of nutrient medium having removed therefrom, by said spirally-wound membrane, solids having a molecular weight above about 30,000 daltons; b) continuously removing nutrient medium from said interior cylindrical space; c) continuously passing said removed nutrient medium of (b) along the cylindrical outer surface of a tubular membrane material, said membrane material having an average pore diameter of from about 0.2 to 1.2 microns, whereby at least a portion of said nutrient medium passes through said tubular membrane material into the hollow cylindrical interior thereof; d) continuously introducing microorganisms into said hollow cylindrical interior of said tubular membrane material for contact with nutrient medium therein; e) maintaining in said hollow cylindrical interior of said tubular membrane material conditions effective to propagate said microorganism in said nutrient medium; and f) continuously removing from said hollow cylindrical interior propagated microorganisms and nutrient medium.

Claim 21

The process according to Claim 17 wherein a gaseous material is inter-mixed with said removed nutrient medium of (b).

Claim 22

The process according to Claim 18 wherein said microorganism is yeast and wherein said gaseous material is an oxygen-containing gas-

Claim 23

A process for continuously culturing microorganisms which comprises, establishing a flow of purified microorganism culture medium into a reaction zone comprised in means for purifying an impure culture medium by passing the impure culture medium through an ultrafiltration device effective to reject solids having molecular weights greater than about 30,000 daltons and at least one additional filtration device having an average pore diameter of from about 0.2 to about 1-2 microns, the filtration devices being effective ir. combination to reduce the contaminating microorganism count of the impure culture medium; continuously advancing microorganisms through said reaction zone under conditions effective to propagate the microorganisms; and separating proprogating microorganisms from excess culture medium.

Claim 24

A process for continuously culturing microorganisms which comprises, establishing a flow of purified microorganism culture medium into a reaction zone comprised in means for purifying an impure culture medium by passing the impure culture medium through an ultrafiltration device effective to reject solids having molecular weights greater than about 30,000 daltons and at least one additional filtration device having an average pore diameter of from about 0.2 to about 1-2 microns, the filtration devices being effective ir. combination to reduce the contaminating microorganism count of the impure culture medium; continuously advancing microorganisms through said reaction zone under conditions effective to propagate the microorganisms; and separating proprogating microorganisms from excess culture medium.

Claim 27

The apparatus according to Claim 21 wherein said spirally-wound membrane is effective to remove from said nutrient medium solids having a molecular weight above about 30,000 daltons and wherein the average pore diameter of said tubular membrane is from about 0.2 to 1.2 microns.

Claim 28

The apparatus according to claim 21 or22 further comprising means for introducing a gaseous material into the annular chamber about the cylindrical outer surface of said tubular membrane.