Controller 5 with input from flowmeter 6 and output to control valve 7 acts to control the flow of an oxygen reducing {HEAD ~ agent} such as {TAIL ~ an alkaline sulfite} 11, with sodium sulfite being preferred, to maintain an operator selectable ratio of reducing agent flow 11 to flow of stream 1 
such as
Controller 5 with input from flowmeter 6 and output to control valve 7 acts to control the flow of an oxygen reducing { HEAD ~ agent } such as { TAIL ~ an alkaline sulfite } 11 , with sodium sulfite being preferred , to maintain an operator selectable ratio of reducing agent flow 11 to flow of stream 1
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 REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH