HD Q-PAC® Structured Media

Structured Geometry for Separation and Biotreatment

Random packings shift during operation; HD Q-PAC maintains its geometry. The structured modules stack into precise beds with consistent void channels, enabling predictable flow patterns essential for oil-water separation and uniform biofilm distribution in biotrickling filters.

The same needle-grid principle that makes Q-PAC effective for mass transfer creates ideal conditions for both applications: 75,000 drip points per cubic foot provide extensive attachment surface for biological growth, while the open structure prevents channeling and dead zones.

Oil-Water Separation: Beyond Stokes' Law

In oil-water separator service, HD Q-PAC achieves Reynolds numbers below 100 — a regime where droplet behavior departs from simple Stokes' Law predictions. The result is oil separation performance that exceeds theoretical expectations based on surface area alone. Field installations consistently achieve non-detectable discharge concentrations under actual worst-case conditions, not just design scenarios.

HD Q-PAC meets both API 421 and EN 858-1 standards for oil-water separator media.

Biotrickling Filters: The Surface That Grows

Unlike flat surfaces where biofilm restricts flow, HD Q-PAC's three-dimensional rod structure actually increases effective surface area as biofilm develops. The rounded surfaces and 90° intersections allow mature biofilm to slough naturally before anaerobic dead zones form, maintaining aerobic conditions throughout the bed.

This self-regulating biofilm behavior enables sustained 98%+ H₂S removal over multi-year operating periods in documented municipal and industrial installations.

Self-Cleaning Design

The same open structure that supports biofilm development resists plugging from particulate loading. Solids pass through rather than bridging across rod intersections. In oil-water separator service, this means longer intervals between maintenance; in biotrickling service, it means reliable operation even with variable inlet loading.