In this installment of Ask The Experts, noted process control authority and CONTROL Columnist Béla Lipták and his cadre of automation experts answer a readers question regarding control valves for slurry services.
There are two main drivers for partial stroking of valves in safety systems: the desire to extend manual test intervals to as long as possible; and to reduce the amount of redundant hardware required for higher safety integrity levels. Like most things in life, it all boils down to one thing: trying to save money.
Measuring flow rates and volumes of water and chemicals in the water, wastewater and chemical treatment industries requires the latest, simple to use and cost-effective technology that can keep up with the rigorous demands of the various applications.
Understanding the fundamentals of fluid agitation can help meet the customers requirement and the processors need for efficiency. While portable mixers have been around for years, they often arent used to their full potential. Knowing the basics of mixing and flow patterns can help you get more out of your mixer.
Author: David Dickey, MixTech, Inc. and Lydia Booth Fenley, Illes Seasonings & Flavors
Design provides improved reliability in a polymer-precursor batch reactor. Sensors must respond quickly and survive a harsh environment. Poor probe reliability can make the difference between a process that makes money and one that doesnt.
Quest for more reliable readings prompts development of tougher and more-intelligent sensors. While pH control often plays a crucial role in processing, achieving reliable readings remains challenging at many sites. After all, pH sensors frequently serve in aggressive chemical environments.
The New Sampling/Sensor Initiative or NeSSI that replaces tubing, fittings and other hardware in a sampling system with miniature modular components makes sense. Enhancements now in the works should assure its success.
ControlGlobal.com contributor David W. Spitzer provides a look from a process automation perspective at how magmeters and Venturi meters are vying with ultrasonics for clean and dirty water applications.
Handling slurries (a mix of solids and liquids), should be based on experience and experiments, not theory. Much of the knowledge obtained from pneumatic conveyors and fluidization systems can be used in understanding slurries.
Author: Thomas R. Blackwood, Healthsite Associates
When it comes to selecting and sizing control valves and positioners, this article not only helps you pick the right one for the right job, but also includes a valuable valve selection chart you can download!
Some U.S. oil refineries repair their centrifugal pumps every three years while other refineries enjoy an average repair interval of 10 years. Learn about the highest-performing refineries and other petrochemical companies that have significantly reduced pump failures, and how you can obtain the same results.