Abstract: A method for providing improved estimates of properties of a chemical manufacturing process is disclosed. The method employs a process model that includes, or is modified by, scores or other gains obtained from the mathematical transformation of data obtained from an on-line analyzer. Chemical manufacturing processes using the method also are disclosed.

Abstract: A method for providing improved estimates of properties of a chemical manufacturing process is disclosed. The method regesses process variables with scores or other gains obtained from the mathematical transformation of data obtained from an on-line analyzer. Chemical manufacturing processes using the method also are disclosed.

Abstract: A method for providing improved estimates of properties of a chemical manufacturing process is disclosed. The method regesses process variables with scores or other gains obtained from the mathematical transformation of data obtained from an on-line analyzer. Chemical manufacturing processes using the method also are disclosed.

Abstract: A method for providing improved estimates of properties of a chemical manufacturing process is disclosed. The method employs a process model that includes, or is modified by, scores or other gains obtained from the mathematical transformation of data obtained from an on-line analyzer. Chemical manufacturing processes using the method also are disclosed.

Abstract: A method for monitoring and improving the performance of a chemical manufacturing process by monitoring transients associated with the operation of process equipment located dowstream of upstream equipment is disclosed. Transients on signals such as the motor current to downstream powder feeding equipment provide early indications of changes in chemical process performance which can then be corrected by altering chemical manufacturing process conditions.

Abstract: A method for monitoring and improving the performance of a chemical manufacturing process by monitoring transients associated with the operation of downstream equipment is disclosed.

Abstract: A method for measuring the concentration of a chemical substance by spectrophotometry comprising the steps of placing a sample of a photoreactive substance between the light source and a spectrophotometer, obtaining an absorption spectrum of the substance using a fixed amount of light from the light source, obtaining a second absorption spectrum after a short interval, comparing the two to determine the concentration of the chemical substance from the difference in the spectra. If the chemical substance is not photoreactive, a photoreactive mixture can be made with a photoreactive dye that has photoreactive properties unique to the mixture. Alternatively, an optically transparent substrate can absorb the substance or the dye/substance mixture.

Abstract: An on-line, fiber-optic based apparatus for monitoring the concentration of a chemical substance at a plurality of locations in a chemical processing system comprises a plurality of probes, each of which is at a different location in the system, a light source, optic fibers for carrying light to and from the probes, a multiplexer for switching light from the source from one probe to the next in series, a diode array spectrophotometer for producing a spectrum from the light received from the probes, and a computer programmed to analyze the spectra so produced. The probes allow the light to pass through the chemical substance so that a portion of the light is absorbed before being returned to the multiplexer. A standard and a reference cell are included for data validation and error checking.