Job description
ABOUT MARIANA MINERALS Mariana Minerals is a software-first, vertically integrated minerals company on a mission to supply the critical minerals powering modern energy, AI, and defense technologies. We’re reimagining the minerals supply chain by combining deep industry expertise with advanced software, automation, and data-driven decision-making.
THE ROLE Mariana Minerals is seeking a highly motivated Staff Process Modeling Engineer to support the development of next-generation refining processes for critical minerals — key to enabling the world’s energy transition. In this role, you will be responsible for developing, validating, and optimizing heat and material balance models using tools such as ASPEN Plus/HYSYS, SysCAD, OLI Studio, or METSIM.
You will work closely with R&D, pilot operations, and project execution teams to translate lab and pilot data into robust, scalable process models that drive the design of first-of-a-kind mineral refining facilities. As a Staff Process Modeling Engineer, you will serve as a technical leader for process simulation and modeling, providing subject matter expertise across multiple projects, developing modeling standards and best practices, and mentoring junior engineers while partnering with cross-functional teams to support process development from concept through commercial deployment.
WHAT YOU’LL DO
- Develop steady-state and dynamic process models to establish heat and material balances for integrated mineral refinery systems using ASPEN, SysCAD, OLI, or METSIM.
- Automate equipment and process sizing (reactors, heat exchangers, filters, crystallizers, evaporators, and separators) based on model outputs, linking models to datasheets and other engineering tools
- Develop and maintain process simulation databases, ensuring consistency and traceability between modeling assumptions, test data, and engineering deliverables.
- Calibrate and reconcile models using pilot or plant operating data to ensure model fidelity and predictive accuracy.
- Conduct process optimization studies — evaluating energy/heat recovery, recycle strategies, and material efficiency improvements.
- Develop dynamic process models to validate PLC and DCS programming and evaluate/optimize buffer sizing throughout the design.
- Link process models to CAPEX and OPEX estimation tools, automating technoeconomic model development
- Document modeling methodologies and results, providing clear technical communication for design reviews, techno-economic assessments, and regulatory submissions. WHAT YOU’LL BRING
- Bachelor's degree or higher in Chemical Engineering, Mechanical Engineering, Process Engineering, Metallurgical Engineering, or a closely related engineering discipline - 8+ years of experience developing and applying process simulation models for chemical processing, hydrometallurgy, mining, refining, or related industrial process systems.
- Proficiency in one or more of the following process simulation tools:
- ASPEN Plus / HYSYS
- SysCAD
- OLI Studio / OLI Flowsheet
- METSIM
- Deep understanding of mass transfer, heat transfer, thermodynamics, fluid flow, and reaction engineering.
- Experience developing material and energy balances for multi-step, integrated process systems.
- Strong grasp of chemical equilibria and phase behavior in aqueous and non-aqueous systems.
- Familiarity with data reconciliation, parameter fitting, and model validation using experimental or operational data.
- Competency with Python or MATLAB for model automation, data processing, and custom calculations is a strong plus.
- Experience integrating process modeling outputs into EPC deliverables (PFDs, P&IDs, equipment datasheets, control narratives, etc.) OUR CULTURE IS BUILT ON THREE PRINCIPLES: Extreme Ownership – We take full responsibility for outcomes, relentlessly driving toward solutions. Engineer Out Requirements, then Automate – We simplify, optimize, and then automate for scale. Share Your Legos – We collaborate openly, share knowledge, and empower each other to build bigger, better solutions. Join us as we build the future of responsible mineral sourcing and supply.