Hopper Bottom Design
Solids buildup is one of the primary reasons oil-water separators fail. When solids accumulate under the coalescer, spread across a flat tank bottom, or migrate upward into the plate pack, the separator loses hydraulic integrity, plugs prematurely, and requires constant shutdowns.
Mercer eliminates that failure mode with a true Hopper Bottom Design—a full-length, sloped solids collection system that continuously draws sludge away from the coalescer and into a concentrated removal zone.
Instead of forcing operators to fight solids accumulation, the tank itself does the work.
Flat and lightly sloped bottoms create:
Once solids accumulate on the floor, they interfere with rise lanes, reduce retention time, and drive inconsistent effluent quality.
A separator without active solids control is a separator on a countdown to failure.
Here is how the hopper actually functions, based entirely on Mercer’s published technical content.
The tank bottom is formed into steep, uninterrupted hoppers that direct every settleable particle to a single low point.
This geometry:
It is a continuously active solids evacuation system, not a passive basin.
As solids fall off the coalescer plates—or as Chimney-Zones™ process solids downward—they enter the hopper immediately, not the tank floor.
This protects the Multi-Pack™ from:
The plate pack stays clean because solids are continuously guided away from it.
Each hopper terminates in a sludge withdrawal point that allows solids to be removed:
Because solids are concentrated—rather than scattered—removal is fast, controlled, and requires minimal disruption.
This is one of the major differentiators noted on the existing Mercer site.
The hopper bottom enables the system to:
This is critical for industrial wastewater, where solids content can change dramatically over time.
Operators report:
The hopper bottom is not a convenience feature — it is a core performance element that keeps the entire system functioning as designed.
If solids are disrupting your separator’s performance, Mercer will test your wastewater and evaluate your current system at no cost.
If testing shows Mercer’s solution will not deliver meaningful improvement, you will know before you commit to anything. Free testing and evaluation are included.
Flat bottoms let solids spread across the tank and migrate into the coalescer. A hopper concentrates solids in one controlled location for predictable removal.
Yes. Because solids are continuously funneled toward the withdrawal point, operators avoid frequent shutdowns and manual under-pack cleaning.
Yes. The unobstructed downward path supports manual, timed, or automated sludge removal systems.
By preventing solids from settling under or rising into the plates, the hopper helps maintain separation efficiency and prevents inside-out fouling.
Yes. Mercer provides free testing and analysis. If a hopper-bottom design will not deliver meaningful improvement, Mercer will say so before you commit.
