Process control system

Claim 1

IN THE HIGH TEMPERATURE, HIGH PRESSURE CONTINUOUS PROCESS FOR THE PRODUCTION OF POLYETHYLENE POLYMERS IN A TUBULAR REACTOR WHEREIN ETHYLENE MONOMER IS INTRODUCED INTO SAID REACTOR AND POLYETHYLENE POLYMERS ARE DISCHARGED FROM SAID REACTOR TO A PRODUCT RECEIVER, THE IMPROVEMENT WHICH COMPRISES CONTINUOUSLY SENSING THE TEMPERATURE OF THE REACTION STREAM AT POINTS SPACED ALONG THE LENGTH OF THE REACTOR TO DETECT MOMENTARY HIGH TEMPERATURE INCREASES IN SAID REACTION STREAM ABOVE A PRESELECTED TEMPERATURE LEVEL INDICATING THE OCCURRENCE OF DECOMPOSITION REACTIONS WITH THE FORMATION OF CONTAMINATING DECOMPOSED PRODUCT IN SAID REACTION STREAM AND DIVERTING THE PRODUCT STREAM FROM THE TUBULAR REACTOR TO PREVENT ITS DISCHARGE INTO THE PRODUCT RECEIVER UPON DETECTION OF SUCH DECOMPOSITION REACTIONS, CONTINUING THE DIVERSION OF THE PRODUCT STREAM FOR A PERIOD OF TIME AT LEAST SUFFICIENT TO DISCHARGE FROM THE TUBULAR REACTOR ALL OF THE DECOMPOSED PRODUCT, AND THEREUPON REDIRECTING SAID PRODUCT STREAM TO THE PRODUCT RECEIVER.