MEASUREMENT OF BATCH PROPERTIES

摘要

A bulk property of a product such as pelletised polymer is monitored during production and used as a control input. The polymer is produced in conventional plant (1). Polymer fluff from the plant flows, along conduit (7) to extruder (8) where it is pelletised. The (10) pellets are fed via conduit (9) to silo (10). The plant is controlled by a computerized control system (6). As polymer passes along conduit (7), weight loss feeder (11) measures its mass flow rate. It is then passed through NIR spectrometer. The mass flow rate and the NIR data (15) are transmitted to data processor (13) where they are used to calculate firstly the instantaneous polymer density and then the bulk density of the polymer in the silo. The output from a data processor (13) is fed to process controller (6) which, if necessary, makes suitable (20) adjustments to process conditions.