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Facts at your Fingertips: Random Tower Packing

Packed Columns [1] A packed column is a vertical, cylindrical pressure vessel containing one or more sections of a packing material over whose surface the liquid flows downward by gravity, as a film or as droplets, between packing elements. Vapor…

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Cover Story: Move Difficult-to-Handle Bulk Materials with Flexible Screw Conveyors

Convey tough bulk materials that tend to pack, cake, smear, break apart or fluidize, and prevent separation of blended products Flexible screw conveyors are suitable for use with most bulk materials, from sub-micron powders to large pellets, both free-flowing and…

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Feature Report: The Number One Problem in a Steam System: Water Hammer

  Water hammer — a high-pressure surge or wave created by the kinetic energy of the moving liquid — is not only a system issue, but primarily a safety concern. Understanding the nature and severity of water hammer in a…

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Engineering Practice: Fired-Heater Burner Performance

  Industrial furnaces, or direct-fired heaters, are only as good as the burners that supply them with thermal energy for heat transfer and endothermic chemical reactions. This article presents equations that permit calculation of such important burner-operating characteristics as flame…

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Facts at Your Fingertips: Membranes

Separation by a membrane is achieved by creating a boundary between different bulk gas or liquid mixtures. As different solvents and solutes flow through a membrane at different rates, separation is achieved. Here, we will focus on three filtration techniques:…

Cover Story Part 1: Are You Ready For REACH?

  This is an important year for any company that makes, uses, buys or sells chemicals or products containing chemicals. On June 1, 2007, the European Union’s (EU) Regulation on Registration, Evaluation, Authorization and Restriction of Chemical substances (REACH) came…

Cover Story Part 2: REACH: A Timely Overview

On Dec. 18, 2006, the European Union (EU) passed a new law creating a single integrated system for the registration, evaluation and authorization of chemicals, which is known as REACH. Described as the most important EU regulation in the last…

Column Instrumentation Basics

An understanding of instrumentation is valuable in evaluating and troubleshooting column performance Instrumentation is critical to understanding and troubleshooting all processes. Very few engineers specialize in this field, and many learn about instrumentation through experience, myth and rumor. A good…

Sensing Change in Batch Reactors

The batch reactor is the workhorse of the fine chemical and pharmaceutical industries. Within it, many different unit operations are performed such as chemical reactions, bioreactions, crystallization, distillation and dissolution. Despite their significance to the industry, batch reactors have been…

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Maintaining and Repairing Heat Exchanger Tubes

Tube plugging is probably the most frequently used maintenance and repair technique for the tube side of an exchanger. This article provides information on how to locate the positions of tube failures and discusses why it is important to know…