The liquid bed can be initially provided by pumping an appropriate liquid into the vessel which is subsequently removed proportionately to the rate that effluent enters the vessel so as to maintain {HEAD ~ a preselected level} of {TAIL ~ liquid} in the vessel 
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The liquid bed can be initially provided by pumping an appropriate liquid into the vessel which is subsequently removed proportionately to the rate that effluent enters the vessel so as to maintain { HEAD ~ a preselected level } of { TAIL ~ liquid } in the vessel
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH