Principal Engineer - Extractive Metallurgy

Position Summary:

The position serves as Redwood's senior technical authority on extractive metallurgy across the company's recycling and refining operations. The role owns the metallurgical basis of design for how Redwood liberates, separates, and refines metals from recycled feedstocks, spanning mechanical separation of heterogeneous feeds, high-temperature processing, hydrometallurgical refining, and electrochemical upgrading of battery metals and other critical minerals. The position exercises independent judgment on methods and evaluation criteria for first-of-a-kind processes where data is incomplete, and its recommendations determine which flowsheets Redwood deploys at commercial scale. This is a strategic individual contributor role with regular interaction with Redwood's CTO and CEO, and success depends on driving innovation and plant deployment at an exceptional pace.

Essential Duties and Responsibilities

• Serves as Redwood's senior technical authority on extractive metallurgy, owning the metallurgical basis of design for recycling and refining flowsheets from feedstock through refined product
• Leads evaluation and selection of competing flowsheet options, translating bench and pilot data into defensible recommendations for commercial deployment
• Owns the metallurgical basis for intermediate and final product quality specifications, diagnosing impurity deportment across unit operations and driving issues to root cause
• Directs strategy for mineral processing and mechanical separation of heterogeneous feedstocks, including comminution, liberation, classification, and physical concentration
• Guides scale-up from bench through pilot to commercial operation, including mass and energy balances, equipment selection, and vendor test campaigns
• Partners with Business Development to define process pathways and pricing for new feedstocks and to identify offtake markets and their value drivers
• Advises operations and process engineering teams on recovery, yield, and reliability shortfalls at commissioned plants, and raises metallurgical rigor across the engineering organization through technical review and mentorship

Skills, Knowledge, and Abilities

• Bachelor's or advanced degree in Metallurgical Engineering, Extractive Metallurgy, Mining Engineering, Mineral Processing, Materials Science, Chemical Engineering, or a related discipline
• 15+ years of experience in extractive metallurgy, mineral processing, or metals process engineering, or equivalent depth of expertise
• Demonstrated ownership of deploying a flowsheet from pilot scale through commercial operation, with accountability for the plant's technical performance
• Deep industrial-scale experience in pyrometallurgy or hydrometallurgy; experience across both preferred
• Hands-on experience in an operating plant environment such as a smelter, refinery, or concentrator, with ability to travel to plant sites as required
• Experience with comminution and physical separation of variable, heterogeneous feedstocks