Clear the Air – Practical briefs for those concerned with air pollution control

Welcome to Clear the Air – briefs for people concerned with real world air pollution control (APC). We strive to publish information that can be of practical value to engineering professionals concerned with meeting emission regulations and/or requirements. While the topics are technical in nature, the content is intended to be informal and relevant to real world applications. We hope to stimulate conversations and information sharing among air pollution control professionals.

We also see these briefs as a forum for your comments or questions. If you have an idea or an observation concerning air pollution control you would like to share, we welcome your contribution. Please contact us, LDX Solutions, with your comments, questions, and feedback.

Gas System flow rate measurement system

Measuring the Flow Rate of a Gas System Perhaps the most fundamental parameter to be measured in gas handling systems is the flow rate. Determining the best method for measuring flow rate can be difficult. For low-pressure, non-toxic gas streams the...

wet Scrubber vs Dry Scrubber differences

Wet Scrubbers vs Dry Scrubbers – Which is Better?   Frequently, wet scrubbers fail to achieve expected performance because the incoming hot gas stream evaporates the scrubbing fluid thus producing a “spray-dried” aerosol. In general, the potential for this...

Gas System Flow RateMeasurement System

Measuring the Flow Rate of a Gas System Perhaps the most fundamental parameter to be measured in gas handling systems is the flow rate. Determining the best method for measuring flow rate can be difficult. For low-pressure, non-toxic gas streams the...

Particulate Matter Isokinetic Sampling

Isokinetic Sampling for Particulate Matter Much time and money are spent by field investigators trying to ensure that particulate sampling is conducted isokinetically; but with today’s tighter emission standards and better control equipment it might be...

wet ESP Corona Quenching Effect

wet ESP and the Corona Quenching effect   Operators of wet electrostatic precipitators (wet ESPs) often notice that the secondary current and voltage readings tend to rise and fall with the particulate loading. This phenomenon is known as space charge...

Wet ESP Limits of Deutsch Equation

wet ESP and the Limits of the Deutsch Equation Those involved in the design of electrostatic precipitators (wet or dry) are familiar with the Deutsch Equation and its variations: The Deutsch Equation Efficiency = 1 – EXP(-AW/Q) Where, A = collecting area W...

Acid Gas Sampling Issues

Potential issues with sampling acid gases Current U.S. Environmental Protection Agency (https://www.epa.gov/) test methods for particulate concentration in stack gases can yield inaccurate results when hydrogen chloride (HCl) is present and the gas stream...

Baghouse Sulfur Sublimation Control

Sulfur Sublimation Control in Fabric Filter Baghouse In the control of emissions from a mineral wool cupola we learned of the interesting phenomenon of sulfur sublimation. Certain forms of elemental sulfur will sublime (vaporize directly from the solid...

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