Hood and air scrubber

Claim 1

A SELF CONTAINED UNITARY HOOD, COMPRISING A WORK STATION, A LIQUID RECEIVING SINK BENEATH SAID WORK STATION, A SCRUBBING CHAMBER POSITIONED IN SAID SINK, ENCLOSED AT ITS UPPER PORTION AND OPENING INTO SAID SINK ADJACENT THE LOWER PORTION THEREOF, AN ENCLOSURE ABOVE AND AROUND SAID WORK STATION, SINK AND SCRUBBING CHAMBER, SAID ENCLOSURE PROVIDED WITH AN OPENING ADJACENT SAID WORK STATION FOR ADMITTING OUTSIDE AIR INTO SAID ENCLOSURE, SAID SCRUBBING CHAMBER INCLUDING A FIXED HORIZONTAL BED OF PACKING MATERIAL AND A PACKING SUPPORTING SCREEN EXTENDING TRANSVERSELY ACROSS SAID CHAMBER, MEANS FOR INTRODUCING LIQUID INTO SAID CHAMBER ABOVE SAID BED OF PACKING MATERIAL FOR FLOODING SAID BED AND FOR DOWN-FLOW BY GRAVITY BOILING IMPURITIES FROM A CRUDE FEED GAS HAVING A MAIN CONSTITUENT BOILING BELOW ABOUT -- 245*C. INCLUDING THE STEPS OF PROVIDING A FEED STREAM INCLUDING SAID MAIN CONSTITUENT AND CONTAINING MINOR AMOUNTS OF SAID LOW BOILING IMPURITIES AT A SUBSTANTIAL WORKING PRESSURE AND A LOW TEMPERATURE BELOW ABOUT -- 150*C.; PROVIDING A WASH LIQUID AT ABOUT SAID LOW TEMPERATURE AND SAID WORKING THE DOWN-FLOWING LIQUID FLOODING SAID BED, THE UPWARD FLOW OF AIR OPPOSING DOWNWARD LIQUID FLOW THROUGH SAID BED AND PROVIDING INTIMATE CONTACAT BETWEEN SAID AIR AND FLOODING LIQUID FOR SCRUBBING SAID AIR, AND MEANS FOR DISCHARGING LIQUID FROM SAID SINK.