(27a) Good Engineering Practice in Protecting Low-Pressure Tanks

It is more than three years since the last edition of API 2000 was empowered and almost ten years since ISO 28300 became worldwide recognized standard in determining venting of atmospheric and low-pressure storage tank.

In this presentation the authors want to introduce the audience to the field of storage tank protection and analyze the common causes for overpressure and vacuum. This presentation will focus then its attention on the rationale behind the methodologies contained in the standard to calculate the venting requirements for some breathing scenarios. Scenarios of interest are here liquid movement and thermal breathing. It will show from which studies they have been derived and how they have been validated on the field. The audience will be given some engineering guidance about other causes of overpressure and vacuum, which are mentioned in the standards but where calculation procedures for venting requirements are missed. The authors will refer explicitly to vapor condensation and overfilling.

The audience can profit from the vast field experience of the authors and their participation in both API 2000 and ISO 28300 committees. Attendance to the presentation is recommended to both graduate students and process safety engineers, wishing to deepen their knowledge on that field.