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Large scale heat exchangers for energy , oil & gas : The growing role of Additive Manufacturing
Energy industries are constantly challenged to become ever more efficient and sustainable . Neither green energy or oil and gas producers are exempt from these pressures , as tight margins and a rapidly evolving regulatory environment mandate increased efficiency in process / output as a core driver for adopting new and improved technologies .
By Dan Woodford - Chief Product Officer , Conflux Technology
Just as important as performance are reliability and minimizing downtime and operational expenditure via serviceable systems and secure part supply , allowing the processes to keep running and maintain their highest levels of output possible . Additive Manufacturing has promising applications in a large number of energy related applications : 3D printed battery electrodes and capacitors , as well as micro-structures that can control energy transfer , leading to solar panel surfaces and refractive coatings , new fuel cell design and photocatalytic reactors . Heat transfer applications are also well suited to deriving significant benefits from additive manufacturing . The generation , and subsequent transfer , of heat is a large part of the process in the creation of stored energy sources , so any advance in technology that lends the opportunity for greater efficiency is one to be explored and progressed . AM can offer a significant impact in the energy industry due to its potential for increasing the efficiency of heat transfer or by intensifying this process so it can occur within a smaller or lighter heat exchanger .
Heat exchangers in energy applications Energy applications typically involve high levels of heat transfer . This translates into one or more of the following extremes : volume , pressure , and / or temperature . Heat exchangers in oil and gas or energy industries are used for key processes like cracking , atmospheric distillation and heat removal from numerous mechanical operations and are typically very large , over 1m 3 in size and up to 20m long in some circumstances . Commonly found heat exchangers include shell and tube style , plate style , tube or pipe . These traditionally manufactured units are relatively scalable as long as there is ample space , enabling design and build of very large units for high volumes of heat transfer – which is required in these industries .
The challenge of energy storage and the role of green hydrogen We can create greener energy , but the next step we need to overcome is the storage of this energy so that it can be used how we want to . Green hydrogen , the frontrunner for storing energy from sustainable sources , uses electricity from appropriate sources to split water molecules by way of electrolysis , extracting the hydrogen , and leaving only oxygen as the byproduct . Storing and transporting hydrogen involve pressure and temperature changes and therefore heat transfer . The most common forms of hydrogen storage and transport currently involve ;
• liquification at extremely low temperatures
• high pressure storage , typically between 350-700 bar
• chemical storage , leveraging metal hydrides , organic compounds or ammonia to convert and extract the hydrogen from a more energy dense and easily transportable form
• gas pipelines , often leveraging / converting existing natural gas infrastructure to accommodate hydrogen
To condense the hydrogen into liquid , where it can be used as the fuel , you need to cool it down via a multi-step process ( the boiling point of hydrogen at one atmosphere pressure is -253 ° C ). Transportation of liquefied hydrogen is complex , involving highly insulated or cooled cryogenic vessels and exacerbated losses due to slopping during transport . Once compressed , hydrogen is ostensibly more transportable , but the density far less than that of liquified hydrogen - 24 or 40 g / L compressed to 350 or 700 bar at room temperature vs 70 g / L for liquid H 2 at 1 atm and -253 ° C . Highly compressed gasses also carry a risk of explosive decompression in an accident . Distributed solutions that enable local condensing of hydrogen bypass the challenges of transportation , but require localized compression or cooling equipment and heat transfer . Commonly envisaged small scale users of hydrogen are ; hydrogen fuel cell electric vehicles ( FCEVs ), hydrogen heat pumps for residential and commercial use and electrical generators .
Conflux Technology ’ s renown fine features and complex internal geometries .
52 Heat Exchanger World September 2022 www . heat-exchanger-world . com