Pacques THEOPAQ® Biogas Purification System Bioreactor in HDPE

HDPE Bioreactor Fabrication for Thiopaq® System – Woodman Point WWTP

As part of the major upgrades at the Water Corporation’s Woodman Point Wastewater Treatment Plant in Henderson, Western Australia, Fusion collaborated with international technology provider Paques to fabricate a 40,000-litre HDPE bioreactor for their Thiopaq® biogas desulphurisation system.

The Woodman Point WWTP upgrade is one of Western Australia’s key infrastructure projects aimed at increasing treatment capacity and improving energy recovery from wastewater. Integral to this initiative is the reduction of hydrogen sulphide (H₂S) from biogas generated during treatment — a challenge addressed by Paques’ proven Thiopaq® technology.

About Thiopaq® and Paques

Thiopaq® is a biological desulphurisation system developed by Paques, a global leader in sustainable water and gas treatment solutions. The process uses naturally occurring bacteria to convert H₂S in biogas into elemental sulphur, making it safer for energy recovery and significantly reducing odour and corrosion.

Founded in the Netherlands, Paques has delivered innovative environmental technologies worldwide for over 40 years. Their systems are recognised for their efficiency, sustainability, and low operational costs — especially in wastewater and biogas treatment sectors.

Fusion’s Role and Fabrication Process

Working closely with Paques’ engineering team, Fusion fabricated the bioreactor using high-quality HDPE sheet, chosen for its outstanding chemical resistance, UV stability, and weldability — all critical for long-term outdoor operation in harsh environments.

Fabrication included:

• Tank shell construction using HDPE sheet and butt welding
• Precision-cut internal components via CNC
• Extrusion welding of complex internal geometries
• Quality assurance and pressure testing to meet project specifications
• Fusion’s WA-based fabrication team ensured the bioreactor was manufactured to exacting standards, on time, and aligned with Paques’ global design requirements.

Benefits of HDPE Sheet Fabricated Tanks

Fusion HDPE sheet-fabricated tanks offer a host of benefits:

• Long service life (25+ years outdoors)
• Superior chemical resistance to aggressive gases and liquids
• No corrosion, even in high-H₂S environments
• Low maintenance with excellent mechanical strength
• Recyclable and environmentally responsible

These advantages make HDPE ideal for biological processes like Thiopaq®, where both structural reliability and chemical compatibility are essential.

Conclusion

This project highlights the power of global-local collaboration. Paques provided the world-leading Thiopaq® technology, and Fusion delivered Australian fabrication excellence. The result is a high-performance HDPE bioreactor, integral to Woodman Point WWTP’s upgraded biogas treatment system — another step forward in sustainable wastewater management.