Join Mitie – the future of high performing places.

ROLE: Technical Process Design Manager
LOCATION: UK Wide Role
CONTRACT: Full Time

At Mitie, our people are our greatest strength, and our promise is to create places where people can thrive and be their best every day. We're looking for a Technical Process Design Manager to join our growing wastewater engineering team, playing a key role in designing and optimising industrial effluent treatment systems across a diverse project portfolio.

Mitie is an accredited Real Living Wage Employer, ensuring all roles are paid at or above the independently calculated Real Living Wage.

Role Responsibilities

Design full industrial effluent treatment plants from feasibility through to detailed design.
Develop and optimise process flow diagrams (PFDs) and P&IDs.
Specify equipment including pumps, tanks, chemical dosing systems, and filtration technologies.
Develop and optimise chemical dosing regimes (e.g. pH correction, coagulation, flocculation, nutrient dosing).
Undertake process calculations, mass balances, and performance modelling.
Support project teams during installation, commissioning, and troubleshooting phases.
Liaise with clients to understand wastewater characteristics and treatment requirements.
Ensure all designs comply with environmental regulations and industry standards.
Contribute to innovation, continuous improvement, and technical excellence within the engineering team.

Required Qualifications

Applicants must meet the below defined requirements for the role.

Degree‑qualified in Chemical Engineering, Process Engineering, Environmental Engineering, or similar discipline.
Proven experience in industrial wastewater or effluent treatment process design.
Strong understanding of chemical dosing systems and treatment chemistry.
Experience with treatment technologies such as DAF, MBBR, SAFS, membrane systems, and dewatering screw presses (or similar).
Ability to produce and interpret PFDs and P&IDs accurately.
Strong analytical, problem‑solving, and technical decision‑making skills.
Comfortable working independently and collaboratively within multidisciplinary project teams.
Excellent communication skills with both technical and non‑technical stakeholders.

What's in it for you?

A key technical role within a growing wastewater engineering team.
Access to Mitie's Choices lifestyle benefits platform, including extra holiday purchase, dental and critical illness cover, and technology schemes.
Virtual GP access for you and your household.
Financial wellbeing support through Salary Finance.
MiDeals high‑street discounts, cycle‑to‑work scheme, and gym offers.
Life cover up to 4× salary, enhanced pension contributions, save‑as‑you‑earn scheme, and the Mitie Matching Share Plan (with potential free shares).
Recognition through Mitie Stars, with monthly cash prizes and an annual £10,000 award.
Strong focus on career development, training, and long‑term progression.

There's a place for you at Mitie, join us today!

Existing Mitie colleagues

Please ensure that you discuss your application with your current line manager before formally applying.
Please note that internal job moves are subject to the standard terms for the post being advertised. Enhanced terms cannot be honoured.

Our market-leading offering provides you with benefits that suit your lifestyle.

We have a virtual GP on hand for you and members of your household. So you can get expert advice by video or phone without having to leave your home. We offer financial wellbeing assistance through our Salary Finance scheme. For example, you could access 50% of your earned pay before payday for a small fee. Salary Finance also offers competitive loans.

When you join us, we’ll give you a link to our flexible lifestyle benefits platform, Choices. You might choose to purchase up to five extra days’ holiday each year. You might buy critical illness insurance, seek dental treatment or buy technology products at an affordable cost. There are many choices!

We give you access to high street discounts from thousands of well-known retailers, gyms and more through our MiDeals platform. And we have a cycle-to-work scheme. Life cover of up to four times your salary is available. We also offer enhanced pension contributions, a save-as-you-earn scheme, and a Mitie Matching Share Plan (you could even be awarded free shares in Mitie).

We award our employees with Mitie Stars as recognition for their hard work. There are cash prizes up for grabs each month and at the end of the year there’s a chance to scoop a top prize of £10,000!

Our success is a direct result of the experience and quality of our people. Progressing your career is therefore a top priority for us. We offer a diverse variety of training and development avenues via a wide selection of learning resources to suit you.

Since 1987, Mitie’s 80,000 employees have been maintaining companies globally. We are the UK’s leading facilities management and professional services company, and our clients range from household names in banking, critical government sites as well as hospitals and schools.

Join our Mitie Team.

Together our diversity makes us stronger.