4976 Bear Mountain Drive

Evergreen, CO  80439

office: 303-670-8392 

cell:  303-670-9092            

e-mail:  bob@procontrol.net            

ProControl, Inc.                   

Process Control Education and Technology                  

  Robert V. Bartman, Ph.D., President                              

Before/After Tower Pressure Stability,

achieved by a refinery’s use of Discover

The following e-mail and graphics were received unsolicited (in November, 2009) from an advanced control engineer at a major overseas refinery.   This refinery enjoys a sitewide license to ProControl’s ‘Discover’ dynamic modeling and loop tuning software, and routinely sends their advanced control engineers to ProControl’s ‘Revelations in Control’ course.

The subject of their e-mail was ‘Discover Testimonial!’ – their words, not ours!  Here’s the main body (there’s a P.S. to come):

Their attached before/after comparison graphic:

There was a P.S. to this e-mail:

Here’s their 2^nd attachment, relevant to their ‘Load Disturbance’ P.S.:

In contrast with the ‘before’ swings in pressure controller OP (orange-ish), the up/down OP changes under Discover’s PID tuning are actually a valid inference of up/down changes in this tower’s vapor rate.