Pressure Vessel Design for Clean Ammonia Demonstration React

We Are Nium Ltd is an innovation-driven clean energy company on a mission to eliminate industrial emissions at scale - starting with one of the world’s most polluting chemical processes: ammonia production. Their proprietary nanotechnology enables decentralised ammonia synthesis at significantly reduced cost and carbon footprint.

To support an upcoming demonstration plant in Australia, Nium required a fully compliant small-scale pressure vessel to operate at high pressure and temperature, forming a key part of their hydrogen–nitrogen to ammonia conversion reactor.

The client provided a concept design for a vessel that is capable of operating up to 32 barg and 450°C, which needed to be:

• Redesigned to improve manufacturability.
• Verified against EN 13445 pressure vessel standards.
• Suitable for third-party certification by DNV Australia.
• Delivered within 8 weeks, from initial brief to approved documentation.

Our role was to take the initial concept and develop a production-ready, standards-compliant design using a combination of software and manual validation.

PKJ Engineering provided a full mechanical design and verification package, including:

➤ Mechanical Calculations:

• Design to EN 13445, using Pv-Elite 2026 and in-house Excel-based      calculations.
• Components covered:
  • Pressure shell.
  • ANSI standard body flange.
  • End cover.
  • Reinforced nozzle openings.
  • Bolting torque and load assessments.
  • Lifting lugs and support brackets (if applicable).
• Note: Wind, seismic, and fatigue load cases were not applicable.

➤Engineering Drawings:

• Full 3D CAD model.
• General Arrangement (GA), Fabrication, and Assembly drawing set.
• Weld Map with location annotations.
• Name Plate Drawing for regulatory compliance.

➤ Collaborative Design Review Support:

As part of the certification process, we supported the client in addressing initial comments raised by DNV Australia. Our team responded quickly and proactively, providing clarifications, design tweaks, and updated documentation to ensure a smooth and timely approval process.

We also worked with the client to incorporate standardised and approved components wherever possible to aid procurement and long-term serviceability. 

The vessel was successfully verified and approved by DNV in Australia, meeting all performance and documentation requirements. Key outcomes included:

• Standards-compliant, manufacturable design delivered in 8 weeks
• Third-party certification achieved
• Contribution to a low-carbon technology with global climate impact potential