Hypochlorite Feed Alternatives News JUNE 2014
Hypochlorite Feed Alternatives News™
Vol. 1, No. 1 Reported independently as Catalytic Objective Synthesis™* June, 2014
Replacement Vacuum Feeders for Hypo Treatment
End Heavy Feeder Maintenance Burden at WWTP
The instrumentation supervisor for the City of Baltimore, MD’s 150 MGD Back River wastewater treatment plant (WWTP) reports that replacement of problematic vacuum feeders with more advanced vacuum feed units has ended heavy maintenance burdens associated with sodium hypochlorite (hypo) treatment of plant effluent.
“There were too many pieces that could go wrong, and then there were too many meetings with operations and maintenance staff complaining they couldn’t get replacement parts,” said Prim Rambissoon, who is also responsible for instrumentation at 12 pumping stations and 15 metering stations. “I’m glad we switched to the more advanced vacuum feed units, which we started installing a year ago, and which have yet to require a maintenance call.”
Each of seven replacement units feeds hypo at approximately 800 gpd, into a group of three contact chambers that hold total plant effluent pending discharge. An eighth feed unit is being installed, and a ninth is on order. Discharge compliance has continued with the replacement units. Once each shift, chlorine titrations are taken to see if more hypo is needed, with adjustment made accordingly, using the new feeders.
Hypo feed began in 2007, with the original vacuum feed units installed in place of chlorinators and evaporators that had fed chlorine gas that was delivered as liquid in railroad tanks. The switch was made to save material costs, and to avoid the need for burdensome approval for tank-stored chlorine near a residential area.