Senior Process Engineer - Pilot Plant & Automation

Doist; San Francisco (CA); On-site; USD 140,000 - 210,000; Full time

Job summary

Mariana Minerals in San Francisco seeks a Sr. Process Engineer to lead the design, deployment, and operation of pilot-scale refining processes for critical minerals, while supporting software-driven plant optimization.

You will bridge R&D and Operations, collaborate with cross-functional teams, and ensure safe, cost-effective, scalable processes from lab to production. This hands-on role requires hands-on leadership, documentation discipline, and a strong commitment to health, safety, and

Qualifications

• B.S., M.S., or PhD in Chemical Engineering or related field.
• 5+ years of experience supporting R&D scale up, pilot plant operation, and/or commercial production in minerals processing, chemicals, or related industries.
• Strong understanding of reaction engineering, solid-liquid separation, leaching, ion exchange, solvent extraction, or similar unit operations.
• Hands-on experience designing, commissioning, and operating pilot or commercial-scale process equipment.
• Ability to design experiments, problem-solve, and analyze complex datasets.
• Strong commitment to Health & Safety and experience with risk management and hazard assessment.

Responsibilities

• Operate and improve pilot-scale processing equipment with technicians.
• Design experiments to evaluate process performance, recovery, throughput, and product quality.
• Create and maintain PFDs, HMBs, P&IDs, Operating Procedures, and Process Control Narratives.

Skills

Process engineering

Experiment design

Data analysis

Technical writing

Education

B.S./M.S./PhD in Chemical Engineering

Job description

Mariana Minerals in San Francisco seeks a Sr. Process Engineer to lead the design, deployment, and operation of pilot-scale refining processes for critical minerals, while supporting software-driven plant optimization.

You will bridge R&D and Operations, collaborate with cross-functional teams, and ensure safe, cost-effective, scalable processes from lab to production. This hands-on role requires hands-on leadership, documentation discipline, and a strong commitment to health, safety, and