Sep-2024

Role of spiral heat exchangers in refineries (RI 2024)

Nexson is a French company based in Garchizy in the Nièvre region. Aware of environmental issues, the company helps manufacturers optimise their manufacturing processes by saving energy.

Dhruv Joshi
Nexson

Article Summary

Every day, it does more to preserve natural resources, providing customers with concrete solutions to combat energy wastage and its impact on the environment. Heat exchangers are integral components in various industrial processes, playing a crucial role in transferring heat between fluids. Among the different types available, spiral heat exchangers (SHEs) have gained significant traction in refineries due to their unique design and efficiency.

Exceptional Heat Transfer Efficiency
SHEs are designed with two concentric spiral channels, allowing for counter-current flow of fluids. This configuration maximises the temperature gradient between the hot and cold streams, enhancing the overall heat transfer efficiency. In refineries, where precise temperature control is essential for processes like distillation and catalytic cracking, the efficient heat transfer offered by SHEs is invaluable. The improved heat exchange capabilities lead to energy savings and optimised operational performance.

Compact Design and Space Utilisation
Refineries often face constraints regarding space, especially in areas with numerous processing units. The compact design of SHEs addresses this challenge effectively. They have a high surface area-to-volume ratio, meaning they can provide a large heat transfer area within a relatively small footprint. This compactness not only saves valuable space but also simplifies the installation process and reduces the structural support requirements.

Reduced Fouling and Maintenance
One of the most significant advantages of SHEs is their self-cleaning nature, which drastically reduces fouling. The spiral design induces a high level of turbulence within the channels, preventing the accumulation of deposits on the heat transfer surfaces. This is particularly beneficial in refineries, where the fluids being processed can often be laden with particulates and other contaminants. Reduced fouling translates to lower maintenance requirements and extended operational periods between cleaning cycles, thus enhancing the overall reliability and uptime of the refinery processes.

Versatility and Adaptability
SHEs are highly versatile and can handle a wide range of fluids, including gases, liquids, and even slurries. This adaptability is crucial in refinery operations, which involve diverse processing streams with varying thermal properties. Additionally, SHEs can operate efficiently across a wide range of temperatures and pressures, making them suitable for different stages of refining processes. Whether preheating crude oil or cooling down final products, SHEs can be tailored to meet specific process requirements.

Robust Construction and Durability
The robust construction of SHEs ensures their durability and longevity, even in the harsh operating conditions typical of refineries. They are usually constructed from materials resistant to corrosion and thermal stress, such as stainless steel. This durability reduces the likelihood of equipment failure and ensures continuous operation, which is critical for maintaining the high productivity levels demanded in refinery environments.

Cost-Effectiveness
While the initial investment in SHEs might be higher compared to traditional shell-and-tube heat exchangers, the long-term cost benefits are substantial. The enhanced heat transfer efficiency leads to lower energy consumption, and the reduced fouling and maintenance needs decrease operational downtime and maintenance costs. Over time, these factors contribute to a lower total cost of ownership, making SHEs a financially sound choice for refineries.

Conclusion
SHEs offer a multitude of benefits that make them well-suited for use in refineries. Their exceptional heat transfer efficiency, compact design, reduced fouling, versatility, robust construction, and cost-effectiveness are key attributes that address the specific needs of refinery operations. As refineries continue to seek improvements in efficiency and reliability, the adoption of SHEs is likely to increase, solidifying their role as a critical component in the refining industry.

This short article originally appeared in the 2024 Refining India Newspaper, which you can VIEW HERE