Harlequin Hydroclear P6 and 16m2 Sand Polishing Filter Kit

Harlequin HydroClear P6 with 16m² Sand Polishing Filter Kit

The HydroClear P6 sand polishing filter package combines a six-person wastewater treatment plant with the components required to construct a nominal 16m² stratified sand polishing filter. It provides a complete treatment and polishing solution for suitable domestic sites that require a pumped discharge.

The package includes a Harlequin HydroClear HC6 treatment plant with a pumped outlet, two grades of tested Biosand, a designed low-pressure pipe network and prefabricated plywood filter panels.

What does the package include?

The package includes:

• Harlequin HydroClear HC6 treatment plant
• Pumped outlet for the sand polishing filter
• Audio and visual alarm
• Two specified grades of Biosand
• Low-pressure pipe network
• Distribution pipework and fittings
• Orifice shields
• Lateral flush valves
• Flush-valve boxes
• Prefabricated plywood filter panels
• Sand-filter schematic
• Pipe-layout diagram
• Installation guidance for the installer

The package does not remove the need for a site-specific design. Therefore, the installer must follow the approved site-characterisation report, planning conditions and wastewater-system drawings.

HydroClear HC6 specifications

• Population served: one to six people
• Typical application: domestic property of up to four bedrooms
• Treatment process: biological wastewater treatment
• Tank material: medium-density polyethylene
• Construction: one-piece rotationally moulded tank
• Nominal hydraulic load: 900 litres per day
• Nominal organic load: 310g BOD₅ per day
• Electrical supply: 230V
• Air-blower rating: 76W
• Published electricity consumption: approximately 1.1kWh per day
• Inlet pipe diameter: 110mm
• Standard inlet invert: approximately 500mm
• Standard gravity outlet invert: approximately 690mm
• Overall length: approximately 2,400mm
• Overall width: approximately 1,200mm
• Overall height: approximately 2,000mm
• Tank weight: approximately 330kg
• Access cover: 600mm × 450mm pedestrian duty
• Tested and certified to EN 12566-3

The pumped-outlet arrangement within this package transfers treated effluent to the low-pressure pipe network serving the sand polishing filter.

Published treatment performance

The HydroClear HC6 has published treatment results of:

• BOD₅ reduction: 97.5%
• Final BOD₅ concentration: 8.7mg/l
• Suspended-solids reduction: 97%
• Final suspended-solids concentration: 12.2mg/l
• COD reduction: 94.4%
• Final COD concentration: 46.9mg/l
• Ammoniacal-nitrogen reduction: 95%
• Final ammoniacal-nitrogen concentration: 2.3mg/l

These figures come from the product’s EN 12566-3 testing. However, actual site performance depends on correct installation, loading, commissioning and ongoing maintenance.

MBBR treatment process

The HydroClear uses a Moving Bed Biological Reactor process. Air from the external blower supplies oxygen to the biological treatment stage, while protected media provide a surface on which treatment bacteria can grow.

Wastewater first enters the primary settlement chamber. It then passes through the aerated biological stage before entering the final settlement chamber.

The treatment plant reduces the wastewater’s organic and suspended-solids load. Afterwards, the pumped outlet distributes the treated effluent across the sand polishing filter for additional treatment.

16m² sand polishing filter

The package provides materials for a nominal 16m² sand polishing filter measuring approximately 4.9m × 3.3m. The final dimensions and construction details must match the approved design.

The filter uses two grades of Biosand arranged in specified layers. Percolation Supplies tests the sand grading, effective size and uniformity coefficient to confirm its suitability for wastewater filtration.

The supplied Biosand:

• Includes both required filter grades
• Undergoes regular grading tests
• Uses hard silica-based material
• Has a rounded particle shape
• Meets the specified effective-size requirements
• Meets the required uniformity coefficient
• Comes with a filter-construction schematic

Do not substitute ordinary building, plastering, concrete or untested quarry sand. Incorrect material can prevent even distribution, restrict drainage or reduce the filter’s treatment performance.

Low-pressure pipe network

The pumped outlet supplies treated wastewater to the low-pressure pipe network. The network then distributes each pumped dose across the filter through small discharge orifices.

The supplied system includes:

• Designed distribution pipework
• Laterals with drilled discharge orifices
• Orifice shields
• End-of-line flush valves
• Valve boxes
• Installation diagram

Orifice shields protect the discharge openings from direct contact with surrounding stone and help reduce blockage risks. Meanwhile, flush valves allow the installer or service technician to clean the laterals during routine maintenance.

Pipe lengths, orifice sizes and pump settings form part of the hydraulic design. Therefore, do not alter the supplied layout without checking its effect on flow and pressure distribution.

Browse our range of low-pressure pipe network components or view other sand polishing filter products.

Installation requirements

A competent wastewater contractor should install and commission the complete system. Before installation, confirm:

• The approved population equivalent
• Site-assessment recommendations
• Planning conditions
• Tank location and inlet invert
• Required filter position and finished levels
• Groundwater and bedrock separation distances
• Electrical-supply location
• Surface-water drainage
• Desludging and maintenance access

Install the tank in accordance with the current Harlequin instructions. In addition, provide suitable electrical protection and connect the blower, discharge pump and alarm through a qualified electrician.

Construct the sand filter using the specified footprint, layer depths and materials. Keep soil and unsuitable stone from mixing with the Biosand during construction.

The system must not receive roof water, yard water, land drains or other surface water. Excess hydraulic loading can disrupt the treatment process and overload the polishing filter.

Servicing and maintenance

Inspect and service the HydroClear system regularly. Maintenance should include:

• Checking the air blower
• Inspecting the diffuser and air supply
• Testing the discharge pump
• Testing the audio and visual alarm
• Checking pump-control levels
• Inspecting the LPPN orifices
• Flushing the distribution laterals
• Checking the filter surface and surrounding ground
• Arranging desludging when required

The published desludging interval is up to 12 months, depending on occupancy and usage. Therefore, determine the actual interval through inspection rather than relying solely on elapsed time.

Always keep access covers visible and secure. Furthermore, never enter a wastewater tank or chamber.

For Irish domestic wastewater requirements, consult the EPA Code of Practice for Domestic Waste Water Treatment Systems.

Contact Percolation Supplies for help confirming whether this HydroClear P6 sand polishing filter package matches the site assessment, planning requirements and approved wastewater design.