Contact Us

Coalescer Pack / Nutshell Filters

High-Efficiency Filtration for Final Polishing of Produced Water

When regulatory discharge requirements demand extremely low oil-in-water concentrations, Nutshell Filters provide an effective tertiary treatment solution. These filters are typically used after primary and secondary separation systems to remove the remaining oil and suspended solids from produced water.

The system uses a blend of pecan and walnut shells as the filter media. The unique surface characteristics of the nutshells enable them to adsorb oil droplets while trapping fine solids, offering reliable, long-term filtration performance with minimal maintenance requirements.

Process Description

Produced water enters the nutshell filter vessel under pressure, passing through the nutshell bed where oil and solids are trapped within the media. Clean water then exits from the bottom of the vessel.

To maintain optimal performance, a backwash process is employed. This process fluidizes the bed, removes contaminated water, allows the filter to settle, and rinses away any remaining impurities. Typically, two filters are used in parallel — one in operation while the other undergoes regeneration — ensuring continuous treatment without interruption.

SPEC’s engineers customize each system design based on flow rate, contaminant load, and discharge specifications, ensuring maximum efficiency and compliance with environmental standards.

Key Features and Advantages

  • Highly efficient and reliable design
  • Compact, skid-mounted packages for ease of installation
  • Blend of pecan and walnut shells for enhanced filtration
  • Excellent oil and solids removal efficiency
  • Backwash system uses process water—no need for an external clean water source
  • ASME-coded vessels ensuring safety and durability
  • Delivers treated water with oil concentrations as low as 5 ppm

Why Partner with SPEC Technology

SPEC Technology’s Nutshell Filter Systems are engineered to achieve high-performance water polishing even under demanding field conditions. With expertise in oilfield technology, turnkey project management, and custom process optimization, SPEC ensures consistent water quality, reduced maintenance cycles, and compliance with international environmental regulations.