2 . Convection : The double-wall design also minimizes convective heat transfer . By preventing direct contact between the high- π www . valve-world . net Valve World November 2024
Explore how new valve technologies are improving residue hydrocracking processes , enhancing safety , efficiency and reactor performance in refinery operations .
By Duke Tran , P . Eng MBA and Luc Vernhes , P . Eng ., Ph . D , Velan
HYDROCRACKING
Valve innovations enhance residue hydrocracking performance
Velan high performance ANSI-2500 isolation valves for residue hydrocracking
Recent advancements in valve design and materials have led to substantial improvements in residue hydrocracking reactors ( RHRs ) operations . These innovations address key issues such as thermal shock , corrosion and the need for precise control in these critical processes . For example , thermal sleeves utilizing advanced materials and manufacturing techniques , like ceramic coatings and 3D printing , have emerged as effective solutions for protecting valves from rapid temperature fluctuations . These designs minimize heat transfer through conduction , convection and radiation , significantly extending valve lifespan and reducing maintenance requirements . Gasket technology has also evolved to meet the demands of RHR environments . High-performance gaskets , including those employing noble metal plating , offer enhanced corrosion resistance , thermal stability and durability . These advancements ensure better sealing performance and reduced risk of leakage , which is crucial for both safety and efficiency in hydrocracking operations . Furthermore , the integration of automation systems , such as Programmable Logic Controllers ( PLCs ) and advanced control panels , has revolutionized valve management in RHRs . These systems enable precise control , efficient purging , optimal heating cycles and enhanced safety protocols . The combination of robust hardware and sophisticated software allows for real-time monitoring and adjustment , minimizing human error and maximizing process efficiency .
Thermal shock protection in valve design
Thermal shock poses a significant challenge in residue hydrocracking operations , where valves undergo rapid temperature fluctuations . During a typical process cycle , catalyst valves may experience numerous thermal cycles ranging from ambient temperature to over 800 ° F ( 427 ° C ). These sudden changes cause different parts of the valve body to expand or contract at varying rates , potentially leading to severe mechanical stresses , cracking or complete valve failure . To address this critical issue , valve manufacturers like Velan have developed advanced thermal protection solutions . One notable innovation in this field is the implementation of Hexashield™ ceramic-coated , 3D-printed thermal sleeves . These sleeves provide a robust thermal barrier that effectively absorbs and dissipates rapid temperature changes , thereby protecting the integrity of the valve body . The effectiveness of these thermal sleeves lies in their ability to mitigate all three mechanisms of heat transfer : 1 . Conduction : Traditional solid metal sleeves readily conduct heat . In contrast , modern 3D-printed double-walled thermal sleeves create an insulating space between the walls , significantly reducing heat conduction . This design principle is similar to that used in vacuum-insulated containers .
2 . Convection : The double-wall design also minimizes convective heat transfer . By preventing direct contact between the high- π www . valve-world . net Valve World November 2024
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