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Sr./Staff Process Engineer - Detailed Engineering and Plant Design

Mariana Minerals· Process Development
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Houston, TXFull-timePosted 5d ago

About the role

Senior / Staff Process Engineer responsible for executing detailed engineering deliverables (P&IDs, line/instrument/valve lists, control narratives, hydraulic models, equipment and bulk specifications, procurement packages) and carrying them through procurement, construction, and commissioning.

Responsibilities

  • Own the process design basis for assigned areas, including design cases, margins, turndown, utility and reagent demands, and first principles basis.
  • Develop PFDs, heat and material balances, and P&IDs; manage metadata behind Plant 3D and related drafting/modeling software.
  • Develop P&IDs from concept through IFC, including equipment, instrumentation/control loops, isolation/relief philosophy, drains and vents, sample and utility stations, sloping and tracing notes, tie-ins.
  • Manage and develop automated workflows for process data behind line/instrument/valve lists (line numbers/sizes, service conditions, design/test pressures and temperatures, pipe class, insulation/heat tracing, instrument data).
  • Build and maintain hydraulic models (line sizing, pressure drop, pump/blower curves, NPSH margin, valve/orifice sizing, slurry/two-phase lines, gravity/vent flows) and evaluate automation opportunities linked to balances and Plant 3D data manager.
  • Size and specify process equipment (pumps, control valves, relief devices, heat exchangers, tanks/agitators, filters, thickeners, mixer-settlers, crystallizers, solid–liquid separation).
  • Write control narratives/functional descriptions with controls team support.
  • Represent process in PHAs and HAZOPs.
  • Coordinate across detailed engineering disciplines (equipment lists/loads to mechanical, motor, electrical and controls; layout, access, maintenance clearances).
  • Support construction and commissioning (RFI/field changes, P&ID walkdowns, field verification, loop checks, functional testing, startup, as-built closeout).

Qualifications

  • 8+ years of process engineering delivering detailed design for industrial process facilities in EPC/EPCM, owner’s engineer, or in-house capital projects environment.
  • Detailed-engineering cycle on at least one greenfield or major brownfield project.
  • BS in Chemical, Metallurgical, or Process Engineering; PE preferred.

Skills

Required:Process design basisP&ID developmentHydraulic modelingEquipment specification
Last updated Oct 21, 2026. Interested? Apply on the company site.

About Mariana Minerals

We to the Future of Minerals, verify the mineral supply chain.

Mariana Minerals is a software-first, vertically integrated minerals company focused on supplying the minerals critical to modern energy, AI, and defense technologies.

software-firstmineralsenergyAIdefense
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