Cool-er Technology Supports Compressor Efficiency and Decarbonization

CO₂ accounts for roughly 80% of greenhouse gas (GHG) emissions, making it the primary GHG associated with human activities. CO₂ levels directly influence the rise in global temperature and contribute to a variety of climate-related issues that have widespread effects on the environment and public health.

Decarbonization is imperative to mitigating climate change, fostering sustainable development, and enhancing energy security. It is a critical goal, and many countries have started implementing stricter regulations and laws around carbon emissions, renewable energy standards, and energy efficiency practices to drive the transition to a low-carbon economy.

Multinational companies are key players in influencing the pace and effectiveness of decarbonization initiatives globally. They are pursuing these initiatives for various compelling reasons, such as regulatory compliance, sustainability goals, corporate social responsibility, market demand, and cost savings.

COMPRESSOR ADVANCEMENTS SUPPORT DECARBONIZATION

Compressors are one of the keys to advancing decarbonization, and recent innovations in compressor technology have increased efficiency, improved performance, and supported the integration of sustainable practices, which allows industries to reduce their carbon footprint more effectively.

Variable speed drives (VSDs): Energy-efficient motor designs and VSDs operate at optimal speeds that reduce energy consumption and associated carbon emissions. Compared to traditional fixed-speed drives that continuously operate at a high pressure, VSD compressors can adapt motor speed to fluctuations in air demand. VSDs have several benefits such as reduced energy costs, no blow-off losses, cost and time efficiency, and minimal leakage.

Gas compressors: These are suitable alternatives for various industries. Hydrogen compressors can handle high pressures for hydrogen storage and transportation while reducing energy consumption and ensuring safety. Ammonia’s excellent thermodynamic properties—despite being toxic in high concentrations—contribute to operational efficiency and sustainability efforts in the refrigeration and chemical production industries.

Heat-to-power system: These systems convert waste heat generated by compressors into electrical energy. They capture waste heat used to drive a thermodynamic cycle, generally through the Organic Rankine cycle, Kalina cycle, or the Steam Rankine cycle. The effectiveness of these systems depends on the temperature and quantity of waste heat available since they are more effective at higher waste-heat temperatures.

Heat recovery systems: About 90% of a compressor’s energy consumption is converted to compression heat, which is typically dissipated to avoid overheating and generally discharged into the air. Heat recovery systems can recover and utilize the vast majority of waste heat generated by compressors, reducing operating costs and CO₂ emissions.

INTEGRATION OF AI AND ML

For improved connectivity, compressors can be equipped with smart digital technologies that provide real-time data insights and monitoring to help optimize performance. Data analytics is used to adjust operations dynamically, which improves efficiency and reduces unnecessary energy usage. Artificial intelligence (AI) and machine learning (ML) algorithms can also be used for:

• Predictive maintenance. Algorithms analyze data and historical failure trends to predict timely repairs and maintenance needs, which reduces inefficiencies and in turn extends machinery lifespan and minimizes overall resource consumption.
• Leak detections. Detecting leaks by analyzing data from vibration, temperature, and pressure sensors enables early or on-time detection and reduces emissions from refrigerant leaks.
• Demand forecasting. Based on historical data and trends, AI can forecast demands for compressed air to avoid over-production.
• Smart cooling systems. Implementing AI and Internet of Things can enable real-time monitoring and optimization of cooling systems, improving operational efficiency and reducing energy/ resource consumption.

Leveraging AI can help better integrate compressors with other system components and energy sources. It can quickly analyze vast amounts of data to provide insights and implementable recommendations that guide decisions to support overall efficiency and enhance decarbonization goals.

COOLING TECHNOLOGIES

Cooling technology plays an important role in compressor performance. Compressors generate significant amounts of heat during operation, so a well-designed cooling system can manage heat and prevent overheating. Compressors tend to operate more efficiently at lower temperatures, as this can reduce the energy required for compression.

Below are some of the recent advancements in this space that are contributing to decarbonization efforts.

Enhanced surface treatments. Textured or structured (corrugations, ribs, or fins) surfaces can increase turbulence in the fluid flow. This disruption increases heat transfer by promoting mixing and improving contact between fluid and heat exchanger surface. Turbulence can also prevent fouling, which degrades heat exchanger performance over time.

Microchannel heat exchangers. These have microchannels to expand the heat transfer area and enhance cooling efficiency. They are generally more efficient than traditional heat exchangers, consume less energy, and are compact. They also require less refrigerant, contributing to lower GHG emissions.

Plate heat exchanger (PHE). Similar to microchannels, these are compact, consume less energy, and have a larger heat transfer surface area. Due to their versatility, PHEs can be easily retrofitted or integrated into existing systems.

Phase-change materials. They absorb and release thermal energy during phase transitions, typically from solid-liquid and liquid-solid. When the temperature rises, they absorb excess heat and store a significant amount of energy in a relatively small volume as they change from solid to liquid. As the temperature drops, they release the stored energy and solidify, providing cooling as needed.

Hybrid and adaptive cooling. Using a combination of air and liquid cooling can optimize performance. For example, a hybrid cooling system can use air cooling during lower loads and liquid cooling during peak loads.

Variable coolant flow. Variable coolant flow rates through coolers allow for greater cooling control based on demand. This can significantly reduce resource consumption and emissions. For example, valves or variable-speed pumps can adjust the coolant flow rate based on real-time data, ensuring efficient operation under varying loads.

Solar cooling. Utilizing photovoltaic (PV) panels to drive cooling processes can reduce your plant’s carbon footprint. Although adequate space is required for panels and thermal collectors, integrating PV panels with existing cooling systems and AI technology can significantly enhance efficiency.

Here are some tips to drive innovation and improvements:

• Integrate thermal energy storage systems to store excess cooling capacity during off-peak hours.
• Optimize operations based on energy availability and demand patterns via compressor interfaces with smart grids.
• Integrate renewable resources to reduce energy demand from conventional sources.
• Minimize heat loss and improve heat transfer effectiveness through research and development of advanced insulation materials.
• Adopt sustainable manufacturing processes and focus on a circular economy.
• Integrate carbon-capture technologies with compressors and explore ways to utilize captured carbon in various processes.
• Further research in heat-to-power compressor systems and integrate into existing compressor setups.

The three Cs: commitment to sustainability, continuous innovation, and collaboration are essential in transforming compressor technology. These advancements in compressor technology not only reduce the direct carbon emissions from compressor operation but also support and contribute to broader decarbonization goals, improving overall system efficiency and enabling sustainable and cleaner solutions.

About the Author

Pavini Shah is a Design Engineer at Ingersoll Rand.