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Exchanger Optimisation
Using vapor infusion to maintain optimal functionality of heat exchangers
By Michael Radicone , Lead Specialty Products - Heat Transfer Research Inc .
What is vapor infusion ? Vapor infusion is an environmentally friendly method that reduces fouling and corrosion in heat exchangers and process equipment that use water as a cooling stream . Vapor infusion safely generates scrubbing , transitory bubbles that reduce the formation of foulants on heat exchanger surfaces and sedimentation while imparting targeted , reduced chemical treatments . Vapor infusion is intended to reduce or eliminate foul formation and progression , maintaining optimum heat exchanger functionality .
How vapor infusion works The vapor infusion system injects ( infuses ) low-dose vaporous chemical treatment periodically into the cooling water flow stream of heat exchangers and process equipment , creating a profusion of vapor bubbles in the flow stream . The vapor bubbles mechanically prevent adherence and solidification of fouling agents while disrupting sedimentary action ( Figure 1 ). The vapor bubble surface chemically treats the internal surfaces of heat exchangers and process equipment to reduce fouling and corrosion ( Figure 2 ). The bubble-to-surface interaction provides targeted chemical treatment while minimizing chemical residue to the water fluid stream . The unique properties of turbulent bubbles provide environmental benefits and disruptive capabilities for removing the initiation of fouling sites and sedimentation . The vapor bubbles have a lower oxygen content which decreases dissolved oxygen and inhibits oxidation corrosion . The effectiveness of vapor infusion has been demonstrated in studies conducted at various universities , with the United States Navy , and with commercial applications . Vapor infusion is effective for any application that uses fresh water , sea water , or water with high levels of organic matter or scaling salt for cooling . Vapor infusion has been successfully implemented on plate-and-frame and shell-and-tube heat exchangers . Processing plants , ships , offshore rigs , aquaculture farms , and geothermal systems applications have all benefited from using vapor infusion . Clients have experienced a decreasing need for manual tear down and chemical cleaning of heat exchangers , as well as a reduction or elimination of the use of chlorine . For heat exchangers that still require manual cleaning , clients have seen a greatly increased time between cleanings . Often , they never need to open their exchangers because the heat exchangers are operating close to design conditions and , when opened to perform inspection after years of use , the exchangers show little fouling of any type ( Figures 3 and 4 ).
Vapor infusion reduces carbon expression It is known that efficient operation of a heat exchangers has a direct correlation to carbon expression through increased energy draw and effects of diminished heat
Figure 1 . Bubble infusion provides disruption of surface foul adhesion and sediment
Figure 2 . Bubble infusion imparts chemical treatment through surface contact www . heat-exchanger-world . com Heat Exchanger World October 2022
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