We are looking for an experienced Lead / Principal Process Engineer to join our team in Kolkata, West Bengal

Experience: 12+ years in Process Engineering / Biochemical Engineering / Mechanical / Piping / in Water-Wastewater / Oil & Gas or related industry

Bio-CNG / CBG Experience: Minimum 5 years

Location: Kolkata | On-site / Hybrid

Employment: Full time

Key Expertise

Process Design & Engineering

· Lead the conceptual design, FEED (Front-End Engineering Design), and detailed process engineering of Bio-CNG plants.

· Optimize anaerobic digestion (AD) systems specifically for tough, fibrous local feedstocks like Napier grass and paddy/rice straw.

· Design efficient feedstock pre-treatment, milling etc systems tailored to handle high-silica and high-lignin materials.

· Develop Mass & Energy Balances, Process Flow Diagrams (PFDs), and Piping & Instrumentation Diagrams (P&IDs;)

Technology Selection & Biogas Upgrading

· Should have knowledge about technologies for biogas purification and upgrading (e.g., membrane separation/ Water Scrubbing/ PSA) to meet IS 16087:2016 standards for commercial Bio-CNG.

· Design and integrate digestate management, solid-liquid separation, and organic fertilizer (FOM/LFOM) production systems.

· Establish process safety frameworks, including leading HAZOP (Hazard and Operability)



studies and adhering to PESO (Petroleum and Explosives Safety Organization) guidelines.

Project Leadership & Lifecycle Management

· Collaborate closely with mechanical, electrical, instrumentation, and civil engineering teams.

· Support plant commissioning, performance testing, troubleshooting, and continuous process optimization

Technical & Feedstock Expertise

· Lignocellulosic Biomass Expertise: Having working experience with agricultural residues; specific experience with Napier grass and Rice Straw is highly preferred.

· Solid understanding of anaerobic digestion chemistry, including C:N ratio balancing, volatile fatty acids (VFA) tracking, and enzymatic or hydrothermal pre-treatment.

· Adequate knowledge in AUTOCAD, can operate and self-sufficient in drawing preparation.

· Familiarity with regulatory frameworks including SATAT initiative guidelines , CPCB norms, and local WBPCB compliance.

Key Competencies

· Problem Solving: Ability to mitigate common engineering challenges, such as high silica wear, floating layers, and slow degradation rates, foaming, etc.

· Communication: Excellent technical writing and presentation skills for stakeholder and vendor alignment.

Interested candidates can DM me or share their CV at [email protected]

📌 Lead / Principal Process Engineer (Bio-CNG) (Kolkata Metropolitan Area)
🏢 Rigel BioEnviron Solutions
📍 Kolkata Metropolitan Area