Liquefaction And Purification Of High Purity Co2 Raw Gas Rbu Plants

Beyond producing liquid CO₂ from CO₂-rich feed gas streams, the RBU concept can support customers in improving the sustainability and competitiveness of their operations. For bioethanol producers, recovering fermentation CO₂ can help reduce the carbon footprint of ethanol and organic compound emissions while creating an additional revenue stream.

At the same time, technologies such as CO₂ Scrub, CO₂ refrigeration, and application-specific process flow design can help reduce site utilities, including water consumption, while supporting reliable product quality and efficient plant operation.

Every RBU plant undergoes a thorough safety assessment in line with EN standards for HAZOP/LOPA and Functional Safety (SIL). This supports safe and efficient operation and helps ensure a smooth CE marking process.

To support reliable operation long after commissioning, Pentair offers tailored Service Level Agreements that combine preventive maintenance, remote diagnostics, performance monitoring, and dedicated technical support. These services help ensure that theplant continues to deliver the required CO₂ quality, operational reliability, and uptime throughout its lifecycle.

For demanding bioethanol fermentation applications, the CO₂Scrub is particularly well suited to removing high-boiling impurities, including aromatic components,  alcohols,oxygenates, and selected sulfur compounds, and maintaining product quality even when feed gas composition and impuritylevels vary.

Unlike conventional water-based purification approaches used in many fermentation applications, CO₂Scrub supports a completely water-free purification process, helping reduce water consumption and environmental impact. In addition, the process requires no chemical additives and produces no liquid or solid waste, supporting more sustainable and resource-efficient CO₂ purification.

Certain CO₂-rich feed gas streams may contain nitric oxide (NO) and other nitrogen oxides that must be removed to meet food-grade or industrial CO₂ specifications. Pentair offers dedicated NOx removal technologies as part of the RBU purification portfolio, selected according to the feed gas composition andrequired product quality. By integrating NOx removal into theoverall purification process,

Pentair helps customers achieve stringent CO₂ purity requirements while maintaining reliable plantoperation and minimizing the impact on operating costs.

For CO₂-rich feed gas streams containing residual hydrocarbons or volatile organic compounds (VOCs), Pentair’s Catalytic Oxidation technology (CATOX) converts these components into CO₂ and water through a controlled catalytic reaction. The process provides an efficient method of removing impurities that cannot otherwise be removed from the CO₂ feed.

By reducing hydrocarbon concentrations before downstream purification and liquefaction, CATOX supports compliance with demanding CO₂ product specifications while helping maximize CO₂ recovery and operational reliability. This technology is particularly valuable for industrial CO₂ recovery applications where hydrocarbon contamination may vary over time.

Pentair’s adsorptive purification technologies are used to remove trace contaminants that may affect CO₂ quality, equipment reliability, or downstream processing. Using activated carbon, molecular sieves, and specialty adsorbents, Pentair can target impurities such as sulfur compounds, alcohols, oxygenates, aromatics, VOCs, and residual moisture.

The technology can be tailored to the specific impurity profile of each application, helping customers achieve demanding CO₂ specifications while supporting reliable and efficient plant operation.