Calorimetric Estimation of Viscosity and Acid Number in Alkyd Reactors

Abstract

In the industrial operation of batch alkyd polymerization reactors, the process evolution is monitored by measuring the acidity and the viscosity of samples withdrawn from the reactor. The synthesis is stopped at the maximum yield allowed by the gelation point of the cold product. In this work, a software sensor that estimates the C(cold)viscosity and the conversion of acid groups on the basis of the continuous measurement of the heat exchange rate between a continuous stirred vessel appended to the reactor and a cooling coil is designed and experimentally tested. The identification of the underlying timevarying observability property yields the designs of the heat exchange devise and of the corresponding robust nonlinear geometric observer. The resulting software sensor is experimentally tested in a pilot plant reactor