ALTEN is a global engineering and technology consultancy operating across over 35 countries worldwide. We partner with industry leaders across sectors including Aeronautics, Aerospace, Defence, Naval, Automotive, Energy, Rail, IT and many more to deliver innovative engineering solutions that drive technological advancement & support sustainable transformation.

Our teams of passionate and agile engineers work on cutting-edge projects that shape the future of technology and sustainability. At ALTEN, we empower talented engineers to innovate, solve complex challenges, and deliver impactful solutions that build tomorrow’s world—today.

Join us and start building tomorrow’s world today!

As a Reactor System Design Engineer you will join Derby team to support our activities within the Nuclear sector. Reactor Systems Design Engineer will be focusing on the Reactor Island Sampling Systems. You will play a key role in progressing the system design to Final Concept Definition (DR3 maturity), working closely with chemistry, systems, and multi-disciplinary engineering teams.

• Location: Derby
• On Site: 2- 3 days on site 
• Clearance: BPSS
• Experience Level: 5- 10 YOE 

Key Responsibilities:

• Lead and support system design and optioneering studies, assessing and comparing design options through structured decision-making methods (e.g. PUGH matrices).
• Develop optimised chemical and fluid system concepts balancing performance, safety, and maintainability.
• Integrate lessons learned and best practices from industry to deliver robust, innovative solutions.
• Define and manage system requirements to ensure alignment with overall reactor architecture and project objectives.
• Use and maintain requirements management tools such as IBM DOORS.
• Bring together multidisciplinary inputs — including mechanical, control, and safety engineering to deliver a fully functional, safe, and efficient system design.
• Apply expertise in fluid flow, heat exchangers, and service condition control to optimise performance and safety.
• Support detailed analysis and design of fluid handling systems, ensuring correct operation under various process and environmental conditions.
• Execute practical design tasks, such as relocating and optimising heat exchangers and defining service integration and control measures.
• Understand and assess both internal and external hazards, ensuring that design solutions meet safety and operational requirements.
• Evaluate how operating conditions affect system performance and interactions across the reactor architecture.
• Contribute to hazard reviews, risk assessments, and design substantiation activities.

Required Skills:

• A chemical, system or  process design engineer with a systems mindset and strong analytical approach.
• Collaborative, able to work across engineering disciplines to deliver integrated design solutions.
• Curious and innovative, driven to improve performance, safety, and sustainability.
• Confident using structured decision-making methods to guide complex design development.

Required Qualifications:

• Degree (or higher) in Chemical Engineering, Process Engineering, mechanical engineering, system engineering  or related disciplinev or equivalent military experience.
• Proven experience in chemical process design, system optioneering, and system integration.
• Strong understanding of fluid systems, heat exchangers, and hazard management.
• Experience in requirements management and use of IBM DOORS (desirable).
• Excellent analytical and problem-solving skills, capable of applying structured engineering methods.
• Knowledge of system architecture, safety integration, and multi-discipline coordination.

Desirable Skills:

• Experience within nuclear, energy, or process industry environments.
• Familiarity with systems engineering standards and requirements traceability.
• Exposure to hazard analysis, HAZOP, or risk assessment processes.

Why join us? 

We bring together entrepreneurial, tech-driven people to deliver innovative solutions for leading companies.

At ALTEN, you’ll work on exciting projects, supported by ongoing learning, mentoring, and clear career development tailored to your goals.

Join a passionate team and help build tomorrow, today.

In short you get: 

• A personalised career path and a rewarding management style 
• A huge diversity of engineering projects and industries
• Private Medical Insurance
• Cycle & Tech Scheme 
• Employee assistance programme
• Life insurance & Pension Scheme
• Social atmosphere, regular gatherings & team buildings
• Flexible way of working (role dependent)

We are proud to support the Armed Forces Covenant & actively encourage applications from members of the Armed Forces community, including veterans, reservists, service leavers, and military spouses/partners. We recognise the value of military skills and experience and are committed to ensuring that no applicant is unfairly disadvantaged during our recruitment and selection processes. 

This role may require you to have or be willing to go through Security Clearance. As part of the onboarding process candidates will be asked to complete a Baseline Personnel Security Standard; details of the evidence required to apply may be found on the government website Gov.UK. If you are unable to meet this and any associated criteria, then your employment may be delayed, or rejected . Details of this will be discussed with you at interview.