Apparatus for the automatic control of a continuous distillation operation for maintaining a constant ratio of bottom product flow to heat input flow

Claim 1

APPARATUS FOR THE AUTOMATIC CONTROL OF CONTINUOUS DISTILLATION PROCESS FOR THE SEPARATION F A FEED STREAM INTO A TOP AND A BOTTOM PRODUCT STREAM IN A DISTILLATION COLUMN IN WHICH BOTH REFLUX AND RE-EVAPORATION ARE APPLIED, COMPRISING: A DISTILLATION COLUMN HAVING A FEED LINE AND TOP AND BOTTOM PRODUCT FLOW LINES, AN ACCUMULATOR, SAID TOP PRODUCT FLOW LINE BEING COUPLED TO SAID ACCUMULATOR; A TOP LIQUID PRODUCT FLOW LINE, SAID TOP PRODUCT LIQUID FLOW LINE BEING COUPLED TO SAID ACCUMULATOR; MEANS RESPONSIVE TO THE VARIATION IN THE LIQUID LEVEL IN SAID ACCUMULATOR FOR ADJUSTING THE FLOW IN SAID TOP LIQUID PRODUCT FLOW LINE TO MAINTAIN THE ACCUMULATOR LIQUID LEVEL WITHIN DESIRED LIMITS; AN ANALYZER FOR CONTINUOUSLY ANALYZING THE QUALITY OF THE TOP PRODUCT WITHDRAWN FROM SAID COLUMN; A REFLUX FLOW LINE COUPLED TO SAID COLUMN AND SAID ACCUMULATOR; FIRST CONTROL MEANS RESPONSIVE TO THE OUTPUT SIGNAL FROM SAID ANALYZER FOR ADJUSTING THE FLOW IN THE REFLUX FLOW LINE TO MAINTAIN THE QUALITY OF THE TOP PRODUCT AT THE DESIRED VALUE; MEANS FOR ADJUSTING THE FLOW IN THE FEED LINE TO A DESIRED INDEPENDENTLY CONTROLLED VALUE; A GAUGE FOR MEASURING THE LIQUID LEVEL IN THE BOTTOM OF THE COLUMN; A FLOW METER FOR MEASURING THE FLOW IN THE BOTTOM PRODUCT FLOW LINE; A REBOILER, SAID REBOILER BEING COUPLED TO SAID COLUMN TO EVAPORATE THE PORTION OF COLUMN LIQUID CIRCULATED THROUGH THE REBOILER; A SOURCE OF HEATING MEDIUM, SAID SOURCE OF HEATING MEDIUM BEING COUPLED TO SAID REBOILER; MEANS FOR MEASURING THE HEAT SUPPLIED TO THE COLUMN REBOILER FOR EVAPORATION; AND SECOND CONTROL MEANS RESPONSIVE TO THE OUTPUT SIGNALS FROM SAID GAUGE, SAID FLOW METER AND SAID HEAT MEASURING MEANS FOR ADJUSTING THE FLOW IN SAID BOTTOM PRODUCT FLOW LINE AND THE FLOW OF SAID HEATING MEDIUM TO MAINTAIN THE COLUMN BOTTOM LIQUID LEVEL BETWEEN DESIRED LIMITS AND TO MAINTAIN A PREDETERMINED CONSTANT RATIO BETWEEN THE BOTTOM PRODUCT STREAM FLOW AND THE HEAT FLOW TO SAID REBOILER.