I D
× COMMENTARYCOVER STORYIN THE NEWSNEWSFRONTSCHEMENTATOR + Show More BUSINESS NEWSTECHNICAL & PRACTICALFEATURE REPORTFACTS AT YOUR FINGERTIPSTECHNOLOGY PROFILEEQUIPMENT & SERVICESFOCUSNEW PRODUCTS + Show More

Comment PDF Environment, Health, Safety & Security

Proper Use of Conventional PRV Discharge Coefficients

By Jung Seob Kim, Sunlake Co., Heather Jean Dunsheath, Covestro, Hyun Ji Woo and Nayeon Kim, SK E&C |

In order to correctly size pressure relief valves (PRVs), a robust understanding of discharge coefficients for vapor, liquid and two-phase flow is crucial A pressure relief valve (PRV) is used to prevent the pressure in a process vessel from exceeding the allowed pressure rating of the vessel. The required PRV orifice area is determined by dividing an ideal nozzle orifice area by a valve discharge coefficient. Therefore, proper use of PRV discharge coefficients is very important for sizing PRVs and preventing potential overpressure of process vessels. PRV manufacturers provide certified discharge coefficients that were determined experimentally for liquids and vapors. Certified PRV discharge coefficient values are reported in the Pressure Relief Device Certifications, NB-18 [ 1] from the National Board of Boiler and Pressure Vessel Inspectors. The certifications are based on isentropic ideal nozzle-flow equations for incompressible flow of water and compressible flow of air and steam. However, there is no certified discharge coefficient for two-phase flow. As many others have noted in the literature, the authors have found that the discharge coefficient for gases is significantly greater than the discharge coefficient for liquids. The…
Related Content

Andritz

Minimizing particle breakage and mother liquor residue in technical salts production

Technical salts and crystallization products have found a broad spectrum of different applications in the industrial sector in the past decades. One of the most frequently used salts is sodium chloride...

Chemical Engineering publishes FREE eletters that bring our original content to our readers in an easily accessible email format about once a week.
Subscribe Now
Metering gas in biogas plants
The Big 6 level measurement technologies: Where to use them and why
Minimizing particle breakage and mother liquor residue in technical salts production
Expectations are shifting: How measurement solutions can help overcome chemical industry challenges
CoriolisMaster: The SmartSensor solution

View More