Specific gravity analyzer and control in an alkylation process

Claim 1

A METHOD FOR THE CONTINUOUS DETERMINATION AND CONTROL OF THE SPECIFIC GRAVITY OF THE ACID STREAM IN AN ACID CATALYZED ALKYYLATION PROCESS COMPRISING THE FOLLOWING STEPS: (A) DIVERTING A PORTION OF THE ALKYLATION PROCESS STREAM SO AS TO FORM A SAMPLE STREAM; (B) HEATING SAID SAMPLE STREAM; (C) STRIPPING SAID HEATED SAMPLE STREAM OF LIGHT HYDROCARBONS AND SKIMMING OFF LIQUID AKYLATE; (D) COOLING AND THEN MAINTAINING SAID SAMPLE STREAM AT A DESIRED TESTING TEMPERATURE; (E) PASSING SAID SAMPLE STREAM THROUGH A COLUMN OF KNOW HEIGHT AT SAID TESTING TEMPERATURE; (F) TAKING THE DIFFERENTIAL PRESSURE OF THE PRESSURE EXERATED BY SAID SAMPLE STREAM IN SAID COLUMN AND THE PRESSURE EXERTED BY AN AIR STREAM OF KNOWN AND SELECTABLE PRESSURE WHEREIN SAID AIR STREAM IS ADJUSTED TO THE DESIRED PRESSURE LEVEL BY PASSING A PORTION OF SAID AIR STREAM INTO A MERCURRY POOL AND THREEAFTER REGULATING THE FLOW RATE OF THE TOTAL AIR STREAM UNTIL SAID PORTION OF SAID AIR STREAM DISPLACES A COLUMN OF MERCURY OF DESIRED HEIGHT; (G) UTILIZING SAID DIFFERENTIAL PRESSURE TO CONTROL ACID FLOW INTO SAID ALKYLATION PROCESS STREAM.