Hubbell, Roth & Clark, Inc. (HRC) was retained by Michigan Automotive Compressor Inc. (MACI) to evaluate and suggest improvements, revisions and/or modifications to their manufacturing facility's existing potable water treatment system. MACI's existing treatment system was based on a multiple pressure vessel iron filtration system and ion exchange softening system to provide filtered water for plant personnel uses and filtered/softened water for various plant processes. Due to planned expansion of the manufacturing facility, additional water treatment capacity was required. Furthermore, the existing treatment system presented several operational and maintenance concerns. To address the requirements for future capacity and improved operations, HRC recommended complete replacement of the existing filtration, softening, and pumping system.

HRC provided design engineering and bid phase services for replacement of the existing water treatment system. The new treatment system utilizes a single, multi-cell horizontal pressure filter (HPF) with manganese greensand media to remove both iron and manganese. The HPF utilizes a simultaneous air and water backwash system to completely agitate and remove solids and reduce backwash volume. The previous aging booster system was replaced with a new booster pump skid and hydropneumatic tank to ensure instantaneously available flow to all facility processes and downstream reverse osmosis (RO) system. Existing softening units were replaced with newer, fully automatic, ion exchange vessels complete with new brine feed system and hard/soft water blending system.

Staged construction of the new system was required to allow the existing equipment to remain in operation during the construction period and ensure minimal downtime to the MACI facility water treatment system. Additional work included modification and rerouting of existing plant piping, and design of a new backwash storage and pumping system and elevated steel platform for the hydropneumatic tank. All controls are fully automatic using programmable logic controllers (PLCs) and pneumatically operated valves.