Adequacy of Hydrocracker Emergency Relief System Case Study

The Challenge

A refinery approached ioMosaic for the purposes of ensuring that pressure relief capacity was adequate for the loss of liquid seal scenario in a high-pressure separator (2,000 psig). They were also concerned about the pressure waves that would occur in the high-pressure separator’s outlet lines on rapid closing of the isolation valves and sought our expertise.

Our Approach

Using our SuperChems™ Expert software, a component of Process Safety Office®, we were able to model the system between the high-pressure separator and the down stream vessel. The system consisted of three parallel flow paths. In one path, there was a power recovery turbine that was modeled. The other two flow paths contained control valves. The fluid flowing in the piping was a mixture containing twelve compounds, which were also included in the modeling.

The Benefits

Using the SuperChems™ simulations we were able to show that the relief valves and piping were adequate for the flow of gas that would be encountered on loss of liquid seal, and that the downstream vessel would not be subject to a pressure greater than its MAWP. Lastly, an optimum valve closing time was determined that would not result in pressure waves that could cause failure of the upstream piping.

Learn More

Our mission is to help you protect your people, your plant, your stakeholder value and our planet. To learn more about how we can help you manage risk, call us at 1.844.ioMosaic.