Role – Mechanical Project Engineer
Location – Lincolnshire
Mint Selection are working with a leading UK biomethane developer who are seeking an experienced Mechanical Project Engineer to join them on a freelance basis during 2026, supporting the delivery of a large-scale anaerobic digestion and biomethane facility.
This role will play a key part in taking the project from pre-construction through construction, installation, commissioning, and handover, with a strong focus on mechanical systems and site-based delivery.
Scope of Work
* Take ownership of the mechanical delivery scope for the AD and biomethane plant, from detailed design review through installation, commissioning, and handover.
* Manage and coordinate mechanical contractors and OEMs, including digesters, mixing systems, pumps, process pipework, gas handling, upgrading, and flaring systems.
* Review and challenge mechanical designs, specifications, and drawings to ensure they are buildable, compliant, and aligned with performance requirements.
* Act as the primary mechanical interface between civils, electrical, controls, and process disciplines to ensure coordinated site delivery.
* Support procurement activities including technical bid reviews, vendor clarifications, factory acceptance testing, and expediting of mechanical packages.
* Oversee mechanical installation on site, ensuring works are carried out safely, efficiently, and in accordance with drawings, specifications, and quality standards.
* Ensure full compliance with Health, Safety, Environmental, and Quality standards, including CDM Regulations.
* Support construction planning, sequencing, and programme management in collaboration with the Project Manager and Site Manager.
* Lead and support site acceptance testing, cold and hot commissioning, and performance testing of mechanical systems.
* Identify and proactively manage mechanical risks, technical issues, and interface challenges, escalating where required.
* Support project close-out, handover, and as-built documentation, ensuring mechanical systems are completed, tested, and signed off to the required standards.
Experience to be Considered
* Proven experience as a Senior Project Engineer or Mechanical Project Engineer on anaerobic digestion, biomethane, biogas, wastewater, or similar process-based energy projects.
* Strong background in mechanical engineering, with hands-on delivery experience across digesters and tanks, mixing and pumping systems, process pipework and valves, and biogas handling, upgrading, and injection systems.
* Experience working in construction and commissioning phases, ideally on live, operationally critical assets.
* Strong understanding of interfaces between mechanical, electrical, controls, and civils disciplines.
* Experience managing mechanical contractors, OEMs, and suppliers in a site-based environment.
* Sound knowledge of Health, Safety, Environmental, and Quality requirements and safe systems of work on complex construction sites.
* Excellent communication and coordination skills, with the confidence to challenge contractors and drive delivery.
This will be a 12-month renewable contract, outside IR35.
If interested, please apply within or contact Harry Arnold for further information.