Project Name: STP THP Overhaul
Location: Southeast Queensland
Contract value: $1,200,000
Duration: 12 months
Project Overview
BDR Stainless was engaged to respond to a critical unplanned failure of the Thermal Hydrolysis Process (THP) system at a sewage treatment plant in Southeast Queensland— a key asset in the utilities biosolids treatment network. The THP system had suffered a significant mechanical breakdown, rendering it inoperable ahead of the critical winter load period.There was no existing repair scope. It became BDR Stainless’ responsibility to investigate, diagnose, and restore the system safely, efficiently, and in line with operational deadlines.
Scope of Work
Our multidisciplinary team led a full-service recovery and engineering response, which included:
- Detailed mechanical inspection and fault finding of all THP pressure vessels and associated systems.
- Scope development and engineering planning, in consultation with the client and OEM technical documentation.
- Finite Element Analysis (FEA) performed through our trusted network of specialist mechanical engineers to assess stress and fatigue on critical components.
- Rectification and mechanical overhaul of key system components, including pressure vessels, valves, and process pipework.
- Design and implementation of improvements to mitigate recurrence and improve system resilience.
- QA documentation and commissioning support to ensure safe reinstatement of service.
Challenges & Response
This project presented several unique challenges:
- No Predefined Scope: The initial engagement was purely investigative. BDR Stainless was tasked with identifying the root cause, developing the scope, and executing the works — all under urgent time constraints.
- System Criticality: The THP system plays a vital role in biosolids handling. Downtime had to be minimised to prevent disruption to downstream processes, particularly ahead of colder seasonal conditions.
- High-Pressure Assets: The system included pressure-rated vessels requiring rigorous safety compliance and certification.
Through fast mobilisation, clear communication with Urban Utilities, and strategic use of our extended engineering network, we successfully diagnosed the failure modes and delivered a comprehensive repair solution.
Outcome
The THP system was returned to full operational condition on time, within budget, and without incident. Our works allowed the facility to resume high-load biosolids processing ahead of the winter period, with improvements made to future-proof the system and reduce the risk of recurrence.
This project highlights BDR Stainless’ strength in:
- Rapid mechanical response to critical failures
- Collaborative engineering and analysis
- End-to-end delivery, from investigation through to rectification and commissioning
