From pilot to plant – scaling carbon capture through reliable measurement

As carbon capture moves from pilot projects to commercial operations, maintaining stable process performance becomes more challenging. Refineries, gas processing plants and hydrogen production facilities must accommodate fluctuating gas compositions, changing operating conditions and continuous production requirements.

At pilot scale, instruments are often used to validate processes under relatively controlled conditions. Commercial facilities require accurate, repeatable measurements over extended operating periods, frequently with limited opportunities for maintenance. Measurement reliability directly affects process control, energy consumption and operating performance.

Critical measurement points in carbon capture

Three measurement locations are particularly important to capture performance: the inlet gas, captured CO₂ stream and tail gas. Each presents distinct requirements for measurement accuracy, stability and response time.

Inlet gas measurement establishes baseline operating conditions. Industrial gas streams can contain varying concentrations of CO₂, moisture, oxygen and other compounds that affect capture efficiency. Fuel switching, upstream process changes and fluctuating plant loads introduce further variability.

Inaccurate or inconsistent inlet measurements can lead operators to maintain conservative operating margins, increasing energy consumption. Continuous monitoring allows process conditions to be adjusted as gas composition changes, helping maintain efficient capture performance.

Captured CO₂ measurement verifies gas composition and quality before compression, transportation, storage or utilisation. Moisture is particularly important because the presence of water in CO₂ systems can contribute to carbonic acid formation and corrosion in carbon steel pipelines and pressurised equipment.

Accurate composition and trace-moisture measurements help operators maintain downstream quality specifications and protect infrastructure intended for long-term service.

Tail gas measurement indicates capture performance by monitoring residual CO₂ in the gas exiting the process. Changes in composition may indicate solvent degradation, temperature imbalances or other developing operating problems. Continuous data allows operators to identify deviations, evaluate capture performance and support emissions reporting.

Continuous measurement under industrial conditions

Scaling carbon capture also requires instrumentation suited to demanding process environments. Corrosive gases, particulate matter, solvent carryover and changing moisture conditions can affect measurement reliability, particularly at capture inlets and outlets.

Traditional analytical methods, including gas chromatography, provide detailed composition data but can require complex sampling systems and ongoing maintenance. Measurement delays may also limit their suitability for applications requiring rapid adjustments to process conditions.

Inline measurement provides a more immediate view of gas composition, helping operators respond to process changes without waiting for periodic analysis.

Vaisala's MGP241 multigas CO₂ instrument, for example, uses patented CARBOCAP® infrared technology to measure CO₂ and water vapor simultaneously. The instrument measures directly in the process without requiring gas sampling or conditioning. Its rapid measurement cycle, long-term stability and compatibility with industrial control systems support continuous monitoring with minimal routine maintenance.

This approach reflects Vaisala's broader expertise in industrial gas and humidity measurement, where measurement stability and reliability over time are essential to effective process control.

Measurement and energy efficiency

Energy consumption remains a major factor in the economics of commercial carbon capture. Solvent-based systems require substantial energy for regeneration, while downstream compression adds to operating costs.

Measurement uncertainty can increase energy demand when operators maintain wider temperature, pressure and flow margins to protect process stability. In regeneration systems, excess steam consumption can be particularly costly.

Reliable gas composition and moisture measurements provide the process data needed to assess capture performance, respond to changing conditions and refine operating parameters. Greater measurement stability can help operators maintain tighter control limits without compromising capture performance.

For facilities operating continuously, even incremental improvements in process control can have meaningful implications for energy use and operating costs.

Engineering for long-term measurement reliability

Instrumentation decisions made during process design affect performance throughout a facility's operating life. Beyond initial accuracy, engineers must consider response time, measurement stability, maintenance requirements and compatibility with existing control infrastructure.

Consistent CO₂ quality measurement will also become increasingly important as transport, storage and utilisation networks establish more standardised impurity specifications.

Vaisala's experience in industrial measurement provides a foundation for addressing these requirements, with technologies developed for continuous operation under demanding process conditions.

As carbon capture reaches commercial scale, reliable measurement becomes an integral part of process design and operation. Accurate, timely data helps operators maintain capture performance, manage energy consumption and meet the quality requirements of the expanding CO₂ value chain.

Download Vaisala’s CCUS eBook to explore the latest developments in CCUS and discover how measurement can support more reliable carbon capture performance.