By Johan Sandberg, Safety Expert, Emerson Automation Solutions

As you know, overfills are a major problem to the process industry in general, but especially so for bulk liquid storage tanks where the consequences can be catastrophic. The industry and society in general are currently investing considerable resources to increase the safety at tank farms. Today the basic overfill prevention technology at many facilities with atmospheric bulk liquid storage tanks uses this configuration:

  • Automatic tank gauge (ATG) for continuous hi-accuracy level measurement connected to a DCS or separate tank gauging system and
  • Separate level sensor connected to a manual or automatic overfill prevention system (OPS-Sensor)

This is the recommended minimum configuration for most tank operations according to API 2350.

Two trends – continuous level for the OPS-sensor and Radar technology for the ATG – are now converging and new installations today often consist of two radar level gauges for both level and independent overfill prevention measurements. Two of the main reasons behind this transition is the high reliability of radar technology combined with the efficient proof-testing procedure it offers. Because of the online measurement the latest generation of Radar level gauges can offer remote proof-testing capabilities. However, existing tanks often have practical limitations that make safety upgrades with two separate level gauges cost prohibited:

  • No tank opening available
  • No measurement pipe available
  • Pressurized tank that cannot be opened
  • Hot tank work cannot be accepted
  • Modifications may require tank to be taken out of service
  • Difficult to modify floating roofs
  • Tank’s Custody Transfer Approval may become invalid
  • Restrapping the tank due to modifications
  • Tank may not pass a new pressure test

That’s where a new technology pioneered by Emerson comes in with a solution. Rosemount 5900 2-in-1 Radar Level Gauge is a new technology that allows a single tank opening to be used for both level (ATG) and separate overfill prevention (OPS-Sensor) measurements. This solution offers substantial cost savings compared to using two separate level sensors.

We’d like to offer you a free white paper that walks you through the issues related to overfill protection, the regulatory requirements and the ways in which this novel solution might work for your tank installations. Please click HERE for the white paper.

If you have any questions, just contact Johan Sandberg, or call +46703740705. What are the issues you face in improving safety in bulk liquid storage?

Leave a Reply

Your email address will not be published. Required fields are marked *