Technical & Practical
Effect of Orientation on Heat-Exchanger Performance
The importance of heat-exchanger orientation on process operations is illustrated using a real-world case study from an ethylene oxide/ethylene glycol plant The flow dynamics associated with the presence of both a liquid and a gas (or vapor) phase inside a…
Downcomer Backup Flooding: In Search of the Truth
Correctly identifying flood mechanisms that limit throughput in a distillation column is central to maximizing capacity and debottlenecking. Guidelines for diagnosing the mechanism are described in Ref. 1. This column recounts a case of downcomer backup flooding. Backup from frothy…
Facts At Your Fingertips: Key Considerations for Control-Valve Specification
Control valves ensure safe and efficient operation of process plants by regulating the fluid flow in connected pipes. This one-page reference outlines key considerations for specifying control valves during the design phase of a plant. Valve sizing. The size of…
Root-Cause Failure Analysis of Heat Exchangers: From Postmortem to Prediction
This practical framework can help engineers transition their heat-exchanger diagnostics from after-the-fact investigation to continuous, chemistry-aware forecasting Chemical producers are pushing the limits more than ever. In addition to extending turnaround intervals from 3–5 years to 7–9 years, ethylene producers…
Testing Hydrogen Infrastructure Materials: A Practical Framework
As hydrogen infrastructure expands, existing material-qualification frameworks must keep pace with hydrogen-specific degradation risks, such as embrittlement, stress corrosion cracking, permeation and accelerated aging Hydrogen infrastructure deployment is speeding up in the chemical process industries (CPI). However, the material qualification…
Facts At Your Fingertips: Real-Time Particle-Size Measurement
Particle size is a key parameter in many solids-handling processes, and can have a strong influence on product performance and quality, as well as for effectiveness of downstream operations. One important approach to particle-size measurement is conducting real-time, inline measurement…
Recovering Valuable Chemicals from Vapor Streams Using Absorption
Absorption can pull a high-value component out of an air stream and return it for reuse, often at a lower cost than destroying it Many chemical and biological processes produce a vapor stream that is primarily air, but contains a…
Bulk-Solids Storage and Flow: Silos and Stockpiles
This article provides guidance on the selection and sizing of silos and stockpiles in bulk-solids-handling operations, and clarifies misconceptions surrounding gravity-reclaim storage systems for bulk-solids materials Gravity-reclaim systems for bulk-solids handling rely solely on gravity to withdraw material from storage…
Facts At Your Fingertips: Net Positive Suction Head: NPSHa versus NPSHr
Net positive suction head (NPSH) is a crucial topic for the design, selection and operation of pump systems in chemical process industries (CPI) facilities. This one-page reference provides information about NPSH available (NPSHa) and NPSH required (NPSHr). Hydrostatic pressure Hydrostatic…
Extending the Life of Legacy Rotary Dryers
Rotary dryers are often in operation for many decades after their initial commissioning. This article provides a decision framework to consider whether to upgrade, repair or replace an aging rotary dryer Rotary dryers are fundamental to ensuring product quality and…