C - Chemistry – Metallurgy – 12 – P
Patent
C - Chemistry, Metallurgy
12
P
C12P 7/56 (2006.01) B01D 61/58 (2006.01) C07C 51/42 (2006.01) C12M 1/12 (2006.01)
Patent
CA 2133268
MEMBRANE-BASED PROCESS FOR THE RECOVERY OF LACTIC ACID BY FERMENTATION OF CARBOHYDRATE SUBSTRATES CONTAINING FERMENTABLE SUGARS ABSTRACT OF THE DISCLSOURE A substantially continuous membrane separation process has been discovered in which the known benefits of a cell- recycle fermentor are unexpectedly enhanced because pH is controlled from 4.0 to 5.5 with a nitrogen-containing base, most preferably ammonium hydroxide. The ammonium lactate formed is not precipitated. This allows continuous removal of lactic acid so as to maintain a concentration of lactic acid about 12%, preferably about 6% by wt in the broth, optionally supplemented with thin stillage or steep water, and optionally buffered with protease. When combined with recycle of UF retentate, operating this cell-recycle fermentor allows the build-up of a cell population in the range from above 5 x 109 CFU/ml to 5 x 1010 CFU/ml, which population is much denser than one which can be produced with the specified pH control in a batch fermentor, after self-termination of the fermentation. This super-dense population of cells, in turn, not only accelerates produc- tion of lactic acid but also minimizes contamination by foreign cells; and since the UF retentate is recycled, a relatively large portion of the broth in the fermentor may be withdrawn as a fermentor effluent stream, sufficient to produce a specified high fluid velocity when the effluent stream is flowed over UF membranes used in the UF modules. The high fluid velocity, preferably from 5-10 m/sec, at. relatively flow pressure less than 1140 kPa (150 psig), produces a scrubbing action over the membrane surfaces which are therefore not fouled over long periods of operation. In a batch fermentation with pH control, when the fermentation is self-terminated the total lactic acid present is about 10% by wt (measured by HPLC), though free always < 4%, and the live cell population is lower than 5 x 109 CFU/ml because many cells die as pH drops.
Kim Hyung S.
Russo Lawrence J. Jr.
New Energy Corporation Of Indiana
Rock H. Wayne
LandOfFree
Membrane-based process for the recovery of lactic acid by... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Membrane-based process for the recovery of lactic acid by..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Membrane-based process for the recovery of lactic acid by... will most certainly appreciate the feedback.
Profile ID: LFCA-PAI-O-1517706