Harlequin CAP18 Sewage Treatment Plant

Harlequin CAP18: High-Performance 18 Person Sewage Treatment Plant

If you require a compliant, high-efficiency sewage solution for a large property or small business, the Harlequin CAP18 Sewage Treatment Plant is the ideal choice. Designed for up to 18 people equivalent (PE), this robust system provides a reliable, off-mains wastewater solution perfectly suited for larger domestic installations, schools, small hotels, and small commercial sites. Certified to the UK standard EN12566-3, the CAP18 guarantees market-leading performance and exceptional discharge quality.

CAP Inatalltion Guide

CAP18 Specification Sheet

CAP18 Drawing

The CAP18 system is manufactured from durable Medium Density Polyethylene (MDPE), making it one of the most stable and easiest sewage treatment plants to install. Its advanced design addresses common reliability issues found in smaller packaged plants, ensuring decades of peace of mind.

The CAP18 uses an advanced Moving Bed Biofilm Reactor (MBBR) system—a unique bio-media technology that prevents blockages often associated with older fixed-media designs. This results in an outstanding 96.2% pollutant removal level. This high standard means the final effluent is clean enough for direct discharge into a ditch, stream, or soakaway (subject to relevant Environment Agency/SEPA permits).

Engineered for efficiency and convenience, the CAP18 keeps running costs to a minimum:

• Low Maintenance: There are no mechanical moving parts or electrical components within the tank. Maintenance is safe and easy.

• 12-Month Service Period: At full occupancy, the system only requires desludging once every 12 months, effectively reducing your operating costs.

• Super Quiet: The high-performance linear diaphragm blower is housed in a weatherproof, above-ground external casing, ensuring super quiet operation and easy access for servicing.

• Odourless: The plant is hermetically sealed, eliminating any odour from within the tank.

Easy Installation and Design Flexibility

The lightweight MDPE construction and integrated lifting eyes mean lower installation costs and reduced complexity on site. The CAP15 is available in both gravity and pumped outlet versions to suit any site requirement, including challenging terrains.

CAP18 Sewage Treatment Plant Features at a Glance

• Capacity: Suitable for up to 85 People Equivalent (PE).

• Performance: Achieves 96.2% pollutant removal.

• Technology: Reliable Moving Bed Biofilm Reactor (MBBR) system.

• Material: Durable, one-piece moulded Medium Density Polyethylene (MDPE) tank body.

• Desludging: Industry-leading 12-month desludging interval (reducing operating costs).

• Operation: Super quiet operation via weatherproof above-ground external air blower (105W rating).

• Safety: Fully secured, low-profile 600x450mm pedestrian duty manhole cover.

• Certification: Certified for use in the UK in compliance with EN12566-3.

• Warranty: 2-year warranty (when registered on our website).