10-01-09

Even the World’s PM_2.5 Experts don’t have the Answers! Hot Topic October 1

PM_2.5 measurement and control was the Hot Topic yesterday. There were six really strong presentations with some very important information exchanges. But the bottom line is that we don’t have concrete time tables or even clarity on what the definitions are. On the other hand participants came away with a much better understanding of the problem.

Jeff Ladwig, Global Product Manager BHA-TEX GE Energy, told the participants that conventional needlefelt medias are capable of removing PM_2.5, however operation is critical to efficiency.

Recommended operating the fabric filter around a small window of differential pressure approximately ½” to 1”.
Said new filters should not be cleaned until a normal operating differential pressure is achieved.

The addition of ePTFE membrane can dramatically lower total filterable particulate emissions easily meeting PM_2.5. Additionally, membrane filter bags are more forgiving when process upsets occur. Membrane fabrics will typically operate at a more consistent differential pressure over the life of the filters because fine particulate is not allowed to migrate into the interstices of the media below the membrane surface.

Dr. John Cooper, President Cooper Environmental Services LLC, was very persuasive in asserting that total mercury and heavy metals should be measured directly rather than with the surrogate mercury vapor and PM_2.5. He pointed out a number of inconsistencies in the EPA approach with the new Cement NESHAP. Since this rule could be promulgated prior to one for Utility NESHAP, it stands to reason that decisions made relative to cement will spill over into the Utility rule.

Tom Rose, President ETA (Eastern Technical Associates), gave a balanced overview of all the measurement options. None of them is the complete answer. If the fuel did not change and the precipitator operation was constant then the problem is minor. But with all the variables affecting the relationship between opacity and mass it is a difficult problem.

Ron Myers, Senior Engineer/Environmental U.S. EPA/Office of Air Quality Planning & Standards, walked us through the critical timelines for PM test methods.

· Proposed on March 25, 2009

o Comment period closed May 26, 2009

o Nucor Steel asked for extension

o Over 50 comments received

· Precision Evaluation was performed

· Drafting comment responses

· Drafting final test method rule

· Response on NSR Transition issue to be in separate Federal Register notice

· Expect M201A/202 promulgation in early to mid 2010.

Bob Crynack, President Indigo Technologies, showed test results indicating that heavy metals are concentrated in the small particles which escape the precipitator. The Indigo Agglomerator can be retrofitted to greatly improve precipitator efficiency.

Jeremy Whorton, ThermoFisher, introduced us to a whole new way to measure total particulate including condensibles. The results in testing to date are very impressive. The system is a hybrid of two technologies. By combining the reliability of one method used continuously and the periodic measurement with another which ensures accuracy but minimizes maintenance, you have the best of both worlds.

The bios, abstracts and photos can be viewed as follows

UtilityE-Alert/2009/October 1 - Bios, Abstracts, Photos.htm

The individual slides are in the Particulate Decision Tree and can be viewed as follows:

Jeremy Whorton - ThermoFisher

Start

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Particulate Removal

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Physical

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Component Specification

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