METHODS AND APPARATUS FOR PROVIDING AUTOMATIC CONTROL OF CHROMATOGRAPHIC FRACTIONATING PROCESSES

• US 3,826,905 A
• Filed: 10/27/1971
• Issued: 07/30/1974
• Est. Priority Date: 10/27/1971
• Status: Expired due to Term

• Current Assignee: Aarne J. Valkama, Eero Sihvola, Lauri Hamalainen, Matti Turunen, Rainer Nihtila, Risto V. Puttonen
• Original Assignee: Aarne J. Valkama, Eero Sihvola, Lauri Hamalainen, Matti Turunen, Rainer Nihtila, Risto V. Puttonen
• Inventors: Hamalainen, Lauri, Valkama, Aarne J., Sihvola, Eero, Puttonen, Risto V., Nihtila, Rainer, Turunen, Matti
• Primary Examiner(s): Botz, Eugene G.
• Application Number:
  US05/192,881
• Time in Patent Office: 1,007 Days
• Field of Search: 137/93,88,119,2 55/67,197,386 356/116 23/230 235/151.35,151.12
• US Class Current: 700/271
• CPC Class Codes: G01N 30/82 Automatic means therefor
• CPC Class Codes: Y10T 137/2509 By optical or chemical property

Abstract

As disclosed herein, the angle of optical rotation, concentration, flow rate and temperature of the components such as, for example, glucose and fructose in an aqueous solution emerging from a fractionating process are continuously measured and signals corresponding to the measurements are fed to a computer. The computer calculates the instantaneous and/or average purity and/or the expected purity of the components and, when predetermined purity values are reached, the computer controls the distribution of the various fractions in accordance with a preset program.

Claims

1. In a method for automatically controlling an industrial chromatographic process wherein at least two substances are fractionated chromatographically and emerge from the process with sufficient purity to be extracted and wherein at least one other fraction emerges requiring recycling into the process, the improvement comprising continuously measuring the angle of optical rotation, concentration and temperature of the fractions emerging from the process, calculating the instantaneous and average purity values of the fractions as a preselected function of the concentration, angle of optical rotation and temperature of the emerging fractions, automatically distributing the fractions in accordance with the detection of predetermined average purity values for the fractions and selectively utilizing the calculated instantaneous purity values to effect a change in the distribution prior to attainment of the average purity values in order to preclude the contamination of one fraction by another fraction.

2. A method according to claim 1 comprising the further step of continuously measuring the flow rate of the fractions emerging from the process and utilizing such measurements in the calculation of the instantaneous and average purity of the fractions.

3. A method according to claim 2 comprising the further steps of automatically predicting a purity curve in a discrete number of steps, comparing the predicted steps of the purity curve with the measured values of purity and selecting the most accurate of the two steps in the purity curve to control distribution.

4. A method according to claim 1 in which the process to be controlled is the fractionation of invert sugar into fructose, glucose and recycling fractions and wherein the fructose purity is calculated from the measurements according to the following equation approximated in linear form as F k1 - k2 (A/C) wherein A is the angle of optical rotation and C is the concentration of the emerging fraction from the process and the constants k1 and k2 depend on the measuring condition, including temperature.

5. A method according to claim 4 comprising the further step of automatically modifying the measured angle of optical rotation as affected by the temperature of the emerging fractions in accordance with a predetermined nomograph.

6. A method according to claim 5 wherein a predetermined instantaneous purity value for the fructose is set and wherein the distribution of the fractions is determined in accordance with the detection of the predetermined purity value.

7. A method according to claim 5 wherein predetermined maximum values for the average F-purity are set and utilized to control the changeover from distribution of the glucose fraction to distribution of the recycling fraction and wherein predetermined minimum values for the average F-purity are set and utilized to control the changeover from distribution of the fructose fraction to distribution of the recycling fraction.

8. A method according to claim 5 wherein predetermined maximum values for the instantaneous F-purity are set and utilized to control the changeover from distribution of the glucose fraction to distribution of the recycling fraction and wherein predetermined minimum values for the instantaneous F-purity are set and utilized to control the changeover from distribution of the fructose fraction to distribution of the recycling fraction.