Emerson’s Jennifer Sandstrom explores reliable combustion air flow in today’s post.
Last time, we started to talk about how Emerson’s Industrial Energy group deconstructs a problem to create a reliable solution. Again, remembering the very definition of reliability is something that produces similar results under consistent conditions. We will continue on and discuss how Emerson’s Industrial Energy Consultants systematically create a finished product that is reliable but I take a small divergence first!
Since my last blog post, I had the opportunity to attend Emerson’s Global Users Exchange in Grapevine, Texas—always very well done and incredibly informative. Every time I attend an event like Exchange I am reminded that:
- People all over the world are experiencing similar challenges and pains.
- Necessity does breed invention
- Emerson is busily addressing necessity and are creating some interesting solutions
- And sometimes, Emerson folks are re-educating us about how to apply tools and devices we may already have!
So how does this all tie into Industrial Energy and Reliability? One of the consistent challenges we face is creating consistency from inconsistency especially when we are faced with few alternatives. What could I possibly mean?
A classic and recurring challenge we meet is a reliable combustion air flow. Often duct geometry and availability of straight run are less than ideal, which is not hard to imagine when considering ideal conditions for flow element installation are 30 pipe diameters upstream and 4 pipe diameters downstream…of straight run, that is…no elbows, obstructions or diameter changes. Easy, right?
Let’s just do a quick math check. Consider a boiler combustion air duct that is, effectively, 24 inches in diameter—not huge. This will translate into 60 feet of straight run upstream of the air flow element. I struggle to recall the last time I can remember seeing an installation that conforms to an ideal installation (that’s not to say they don’t exist, just that I cannot recall).
Reality dictates that sometimes confines and challenges will exist so we need to determine how to work within such conditions. Industrial Energy approaches the air flow challenge in this way; first, it would always be our preference to have an ideally sized, designed, located and installed device. Realizing that this is not what we may face our preference then becomes an air flow measurement that is repeatable.
Before you collectively gasp in horror, let’s remember stoichiometry; ultimately, O2 will tell the story of correctly applied air and fuel mixture. At a minimum, if the air flow is repeatable, we will be able to make a consistent response based on another key measurement, O2. But! If we could help make a bad situation better with a solid solution that is not only repeatable, but reliable as well, we certainly want to let our customers know what possibilities exit.
That brings us back to Exchange. If you had the chance to go and attend the session presented by Dave Winters and Buck Kempner of Rosemount, titled Not Just a Lot of Hot Air!, you had a great chance to learn a plethora about Rosemount Annubar, a S-Type pitot tube and dealing with challenges that stand between a user and a reliable air flow measurement.
In their presentation, they took the audience through Annubar basics of function and sizing an Annubar correctly. This a good place to mention that accurate process data is absolutely imperative. The Rosemount dP Flow group has dedicated themselves to making a superior instrument and it is a superior instrument but, ultimately, will only be as good as the data supplied for design and sizing.
Beyond initial specification and sizing an in-line calibration to customize the Annubar “k-factor” can be performed to improve upon the non-standard (code for difficult) installation. This is the part where most engineers’ engineers start to get giddy! (I will not pretend I can do justice to the explanation of the pitot traverse process so I will leave you with a reference to the Code of Federal Regulations (CFR) number 40, part 60 ,this a code detailing protection of environment standards of performance for new stationary sources, and to the folks at Rosemount dP Flow.)
After explaining how to do a pitot traverse, Dave and Buck demonstrated with a demo unit and conducted a miniature in-line calibration. Really a great demonstration on how an in-line calibration would be executed at a customer facility. I am impressed with the tenacity, knowledge and dedication Rosemount dP flow employs to create not only a reliable device but goes the extra distance to help process manufacturers enjoy the benefit of that reliability with proper application and calibration.
I agree there is effort involved but genuinely feel the effort pays back! After all, when was the last time we each had an “opportunity” that didn’t mean applying effort or work to realize the benefits?
For more information on the Annubar – Annubar Flow Handbook and the Annubar Flow Test Data Book.
I hope you enjoyed Exchange, if you had the opportunity to attend, and the divergence to focus on air measurement. Remember there is help and guidance available. Even more important there is a reliable solution!
In future posts, we’ll talk more about how Emerson’s Industrial Energy Consultants put together other key elements to create reliable combustion solutions together and how the approach is applicable to more than just combustion. You can also connect with us in the Industrial Energy track in the Emerson Exchange 365 community.
