Automatic process control method and apparatus

Claim 2

AN IMPROVED METHOD OF CONTROLLING A CONTINUOUS CHEMICAL REACTION WHICH PROCEEDS SHORT OF COMPLETION IN A REACTION ZONE WHICH COMPRISES SENSING THE RATE OF FLOW OF A REACTANT TO SAID ZONE, PRODUCING A FIRST OUTPUT AS A FUNCTION OF SAID RATE OF FLOW OF REACTANT TO SAID ZONE, SEPARATING UNREACTED REACTANT FROM SAID REACTION EFFLUENT AND PASSING SAID UNREACTED REACTANT FROMTHE REACTION SYSTEM, SENSING THE RATE OF FLOW OF SID REACTED REACTANT PASSING FROM SAID SYSTEM, PRODUCING A SECOND OUTPUT AS A FUNCTION OF SAID RATE OF FLOW OF UNREACTED REACTANT, SENSING THE RATE OF CHANGE OF A VARIABLE OF THE PROCESS WHICH PRODUCES A DISPLACEMENT OF REACTANT FROM SAID SYSTEM, PRODUCING A THIFD OUTPUT AS A FUNCTION OF SAID RATE OF CHANGE OF SAID VARIABLE TIMES A FACTOR RELATING CHANGE IN SAID VARIABLE TO THE AMOUNT OF SAID DISPLACEMENT, APPLYING SAID FIRST, SECOND AND THIRD OUTPUTS TO PRODUCE A FOURTH OUTPUT AS A FUNCTION OF THE DIFFERENCE IN POTENTIAL BETWEEN SAID SECOND OUTPUT AND THE SUM OF SAID FIRST AND THIRD OUTPUTS, AND APPLYING SAID FOURTH OUTPUT TO CONTROL A VARIABLE OF SAID REACTION DIRECTLY AFFECTING REACTION RATE.

Claim 3

IN APPARATUS INCLUDING A REACTOR, MEANS FOR FEEDING REACTANT TO SAID REACTOR, MEANS FOR FEEDING SOLVENT TO SAID REACTOR, A FLASH TANK, MEANS FOR PASSING AFFLUENT FROM SAID REACTOR TO SAID FLASH TANK, MEANS FOR WITHDRAWING VAPOR FROM SAID FLASH TANK, AND MEANS FOR WITHDRAWING LIQUID FROM SAID FLASH TANK, THE IMPROVED CONTROL SYSTEM COMPRISING, IN CONBINATION, MEANS FOR SENSING THE RATE OF FLOW OF REACTANT TO SAID REACTOR AND PRODUCING A FIRST OUTPUT AS A FUNCTION THEREOF, MEANS FOR SENSING THE RATE OF FLOW OF UNREACTED REACTANT IN THE VAPOR FROM SAID FLASH TANK AND PRODUCING A SECOND OUTPUT AS A FUNCTION THEREOF, MEANS FOR SENSING THE RATE OF CHANGE IN LIQUID LEVEL IN SAID FLASH TANK AND PRODUCING A THIRD OUTPUT AS A FUNCTION THEREOF, MEANS FOR PRODUCING A FOURTH OUTPUT AS A FUNCTION OF SAID THIRD OUTPUT TIMES A FACTOR FOR UNREACTED REACTANT DISPLACED FROM SAID FLASH TANK PER UNIT INCREASE IN LIQUID LEVEL, MEANS FOR PRODUCING A FIFTH OUTPUT AS A FUNCTION OF THE DIFFERENCE BETWEEN THE POTENTIAL OF SAID SECOND OUTPUT AND THE SUM OF THE POTENTIALS OF SAID FIRST AND FOURTH OUTPUTS, AND MEANS FOR APPLYING SAID FIFTH OUTPUT TO CONTROL A REACTION VARIABLE.

Claim 4

IN APPARATUS INCLUDING A REACTOR, MEANS FOR FEEDING REACTANT TO SAID REACTOR, MEANS FOR FEEDING SOLVENT TO SAID REACTOR, A FLASH TANK, MEANS FOR PASSING AFFLUENT FROM SAID REACTOR TO SAID FLASH TANK, MEANS FOR WITHDRAWING VAPOR FROM SAID FLASH TANK, AND MEANS FOR WITHDRAWING LIQUID FROM SAID FLASH TANK, THE IMPROVED CONTROL SYSTEM COMPRISING, IN CONBINATION, MEANS FOR SENSING THE RATE OF FLOW OF REACTANT TO SAID REACTOR AND PRODUCING A FIRST OUTPUT AS A FUNCTION THEREOF, MEANS FOR SENSING THE RATE OF FLOW OF UNREACTED REACTANT IN THE VAPOR FROM SAID FLASH TANK AND PRODUCING A SECOND OUTPUT AS A FUNCTION THEREOF, MEANS FOR SENSING THE RATE OF CHANGE IN LIQUID LEVEL IN SAID FLASH TANK AND PRODUCING A THIRD OUTPUT AS A FUNCTION THEREOF, MEANS FOR PRODUCING A FOURTH OUTPUT AS A FUNCTION OF SAID THIRD OUTPUT TIMES A FACTOR FOR UNREACTED REACTANT DISPLACED FROM SAID FLASH TANK PER UNIT INCREASE IN LIQUID LEVEL, MEANS FOR PRODUCING A FIFTH OUTPUT AS A FUNCTION OF THE DIFFERENCE BETWEEN THE POTENTIAL OF SAID SECOND OUTPUT AND THE SUM OF THE POTENTIALS OF SAID FIRST AND FOURTH OUTPUTS, AND MEANS FOR APPLYING SAID FIFTH OUTPUT TO CONTROL A REACTION VARIABLE.