Technical & Practical
Waterhammer In Condensate Return Lines
There is a temptation that steam design engineers find difficult to resist — to put condensate from high-pressure (HP) steam mains directly into the low-pressure (LP), pumped condensate-return (CR) mains. After all, the CR main is so convenient — it…
Control Valves: An Evolution In Design
Globe-style control valves are in virtually every chemical processing line where pressure and flow must be controlled. And for the most part, they perform as required, day in and day out, requiring little to no thought or attention. In short,…
A Primer on Gas-Solid Fluidization
The earliest application of the fundamental concepts of fluidization dates back to 16th century when a German scientist (Georgius Agricola) described a process to upgrade ores. However, it was not until the 1930s, with the development of the Winkler coal-gasification…
Internal Corrosion Sampling
Corrosion is a large and complex issue that is critical to the chemical process industries (CPI) as well as other industry sectors. Corrosion not only affects personal property like cars and homes but also affects commercial assets such as storage…
The Unexpected Rewards of Testing a Mixer
Among all the engineers who will be involved in the purchase of a mixer or blender next year, roughly half will welcome a change in their production method. The other half will be determined to prevent it. Searching for the…
Automated Weigh-Batching Systems
Automated systems for batch weighing can improve overall product quality by raising the accuracy and consistency of the mixture compared to what can be achieved with the manual addition of pre-weighed bags. Automated batch-weighing systems integrate load cells with connections,…
Evaluating Green Projects: Modeling Improves Economic Benefits
The ability to model a process to see if it meets project requirements and is economically viable enhances the conceptual design. Modeling gives engineers a means to identify the most promising processes, in terms of capital investment and return, and…
Overpressure Protection: Consider Low Temperature Effects in Design
Understanding the inherent limitations of current overpressure protection analyses is key to developing a more robust heuristic In designing and sizing relief-device and effluent-handling systems, one commonly overlooked aspect of the performance is examining the potential for low temperatures that…
Working with the CSB After a Major Accident
After a serious accident at a chemical plant, petroleum refinery or other freestanding industrial facility, the U.S. Chemical Safety Board (CSB; www.csb.gov) may immediately initiate an investigation, often getting “in the air” while the emergency is still unfolding. The CSB…
Dynamic Modeling for Steam System Control
One of the most energy-intensive utilities for many facilities in the chemical process industries (CPI) is the steam system. Traditionally, steam-use optimization has centered on efficient heat transfer and eliminating waste [ 1]. Further optimization can involve a broader look…