ON-LINE CONTROL OF A CHEMICAL PROCESS PLANT

A process plant for the manufacture of halobutyl rubber is provided with online monitoring and control of the process parameters to control the properties of the product. It incorporates an in-situ measurement system that does not require the removal of any sample material from the process. It uses a Fourier Transform Near Infrared (FTNIR) spectrometer, fiber-optic cables, a viscometer for measuring solution viscosity and a Resistance Temperature Device (RTD) for temperature measurement. An online real-time analyzer system using a Constrained Principal Spectral Analysis program predicts the property of the polymer product and provides the process control system with analysis of the data using derived relationships between the physical properties of the polymer and these spectral measurements and the measured values of fluid viscosity and temperature. Differences between the predicted and desired property of the product are used to control process parameters. The method can be used for a variety of chemical process plants.