Mechanical Engineer

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. We’re reimagining how minerals are sourced, refined, and optimized by combining deep industrial expertise with software, automation, and data‑driven decision‑making.

Join us as we build the future of responsible mineral sourcing and supply.

Mariana Minerals is looking for a highly motivated Mechanical Engineer to work on building the critical minerals supply chain to support the world’s energy transition. As a Mechanical Engineer at Mariana Minerals, you will lead the development and deployment of first‑of‑its‑kind chemical refining processes, while also supporting development of software for project execution and plant optimization. You will design, build, and commission mineral processing and metallurgical refining equipment, develop first‑principles‑based models of refining equipment and processes, and lead equipment scopes from concept through to design, installation, commissioning, ramp, and handover to the operations team.

• Lead mechanical engineering scopes across project phases—from concept and feasibility through detailed design, procurement, fabrication, installation, and commissioning
• Manage vendors throughout the equipment lifecycle—from specification, RFQ, and technical bid evaluation through drawing review and approval, fabrication expediting and inspection (ITP/FAT), delivery, installation and commissioning support, and warranty close‑out
• Develop site‑wide and area‑level plant layouts, optimizing equipment arrangement, maintainability access, constructability, safety, and integration with other disciplines
• Prepare mechanical equipment specifications, data sheets, and requisition packages for a range of process and solids‑handling equipment, and support technical bid evaluations and vendor selection
• Perform static equipment design of tanks, silos, bins, pressure vessels, and other stationary equipment, including mechanical sizing, wall/shell thickness, and structural load calculations ensuring code compliance
• Conduct finite element analysis (FEA) to validate equipment and component designs for stress, fatigue, thermal, and operational loading conditions
• Design, evaluate, and integrate solids‑handling and material‑conveyance systems, including silos, bins, hoppers, feeders, conveyors, bucket elevators, chutes, and dust‑control systems
• Support development of 3D models and piping/mechanical interface layouts, ensuring alignment with process, structural, civil, and electrical engineering requirements
• Review vendor drawings and calculations, ensuring mechanical design compliance with project requirements, codes, standards, and operability/maintainability expectations
• Collaborate with multidisciplinary EPC teams—including process, structural, piping, electrical, instrumentation, and construction management—to deliver cohesive and constructible engineering packages
• Provide mechanical engineering support during construction and commissioning, including responding to RFIs, reviewing field changes, and assisting with equipment installation and start‑up

• Bachelor’s degree in Mechanical Engineering or a related engineering discipline
• Strong understanding of engineering fundamentals and demonstrated ability to leverage that understanding to solve challenging problems
• Experience preparing and reviewing mechanical equipment specifications, vendor documentation, and engineering deliverables for both brownfield modifications and greenfield facilities
• Demonstrated ability to complete static equipment design of tanks, silos, bins, vessels, and other stationary equipment, including code‑based mechanical and structural calculations
• FEA capabilities—proficiency with finite element analysis tools to validate equipment and component designs for stress, fatigue, and thermal/operational loading
• Working knowledge of relevant industry…