The importance of real‐fluid behavior in predicting release rates resulting from high‐pressure sour‐gas pipeline ruptures

The Canadian Journal of Chemical Engineering (Impact Factor: 1.31). 02/1989; 67(1):3 - 9. DOI: 10.1002/cjce.5450670102

ABSTRACT The real fluid nonisentripic decompression model presented by Picard and Bishnoi (1988) was used to evaluate the current practice of assuming perfect gas behaviour when predicting release rates from high pressure sour gas pipelines. It is shown that use of perfect gas theory can result in the transient release rate being underestimated by 30 to 45%, and the total amount of fluid released, underestimated by 50%. Perfect gas theory cannot consider condensation effect; more than 35% of the H2S contained in a pipeline may be emitted as a liquid. Use of the popular "double exponential" model, as presented by Wilson (1979), will result in similar errors. If the model is modified slightly so that the initial mass of fluid in the pipeline is determined based on real fluid theory, than a conservative estimate of the transient release rate may be obtained (i.e., the most rapid release of the fluid is predicted).

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