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Corrosion
Wide range of possibilities for glass-lined tube bundles in various applications( in order: short path evaporator( top left panel), storage vessel, top condenser, with glass shell( middle panel), cold trap, PowerBaffle inside a reactor( right 2 panels), serial connection on product side( bottom).
as well as fouling due to the interaction of the chemicals in the flue gas and the construction material of the heat exchanger. Therefore, the low-temperature waste heat is often not captured and released into the atmosphere. With glass-lined steel tubes, this has changed, and more and more the low temperature deep waste heat is beginning to be captured, thereby considerably improving the overall efficiency. Each 20 ° C reduction in flue gas temperature results in a 1 % thermal efficiency improvement.
Conclusion The glass-lined heat exchanger promises to upend not just the recovery of waste heat, but also a wide range of applications in the production of pharmaceuticals and agrochemicals. In waste heat recovery, a valuable alternative approach to improving overall energy efficiency is to capture and reuse the lost or‘ deep waste heat’ that is intrinsic to all industrial manufacturing. During these manufacturing processes, as much as 20 to 50 % of the energy consumed is ultimately lost via waste heat contained in streams of hot exhaust gases and liquids, as well as through heat conduction, convection, and radiation from hot equipment surfaces and from heated product streams. In some cases, such as industrial furnaces, efficiency improvements resulting from waste heat recovery can improve energy efficiency by 10 % to as much as 50 %. However, due to the challenges presented by low-temperature corrosion at the acid dew point, the deep low-temperature waste heat recovery has been expensive and elusive. The glass-lined heat exchanger promises to change that, enabling recovery of waste heat at the ADP. In the quest for net zero and sustainability, this is a step in the right direction. Glass-lined heat exchangers represent a perfect combination between chemical resistance, cleanability, durability and cost, with
the thin layer of smooth glass lining on a highly conductive but strong steel substrate ensuring high heat flow with greater fouling resistance and lower total cost of ownership. Many applications where deep waste heat recovery was not previously a profitable return on investment are starting to experience change. As such, this is a promising new direction in heat-exchanger design in a multitude of ways.
About the authors
Tom Patnaik serves as the Vice President of Sales & Service for Thaletec USA. He is responsible for creating awareness and recognition for the Thaletec brand of glass-lined reactors, heat exchangers, and columns, as well as growing the installed base in North America. Previously, Tom has served with industry leaders such as Bird Machine, Sanborn, Hosokawa Micron, Heinkel Drying & Separation, and Pfaudler, in various sales and business development capacities within the chemicals, pharmaceuticals and other industries where alloy and glass-lined process equipment is used. As such, Tom brings a wealth of experience in all areas of the pharma-chem process train from size reduction and granulation to filtration, drying, containment and packaging.
Dr-Ing. Christian Stentzel is a mechanical engineering graduate and holds a doctorate from TU Dresden. Dr-Ing. Stentzel is an accomplished researcher and serves as the Head of Research & Development at Thaletec GmbH. www. heat-exchanger-world. com Heat Exchanger World June 2025
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