COMPUTER METHOD AND APPARATUS FOR DETERMINING STATE OF PHYSICAL PROPERTIES IN A CHEMICAL PROCESS

Computer method and apparatus determines state of physical properties, i.e. product quality, of a chemical manufacturing process. A steady state modeler (15) provides a rigorous steady state model of the process and instantaneous state of physical properties. An estimator (21) or inferential sensing membe r determines state of the physical properties over time based on the steady state (instantaneous) values of the physical properties. To that end, a dynamic model of the subject process is formed from the steady state model. The computer method and apparatus may be part of a network such that laboratory and sensor measured process data is made accessible by the steady state modeler and the estimator, and the estimator provides process paramete r values for maintaining state of the physical properties. The network also enables online and user-interactive access to the steady state model, the dynamic model and/or the parameter values for enabling control of the subjec t process.