01-07-10

Particulate removal for High Sulfur Coal-fired Boilers Webinar provided Insights on Membranes, Power Supplies and WESPs

The Hot Topic Hour yesterday, January 7, produced some very interesting insights. Bob McIlvaine talked about the importance of fine particulate compared to CO₂ emissions in terms of harm. A common metric has been devised that rates all activities with one metric. The U.S. power plant emission combination of fine non-toxic particulate plus all the fine toxic metal particulate is the equivalent of 700 million tons of CO₂. In other words by eliminating these emissions you would achieve as much as eliminating 40 percent of the CO₂. The best solution is to upgrade or replace all the existing coal-fired power plants with new supercritical. This will achieve the equivalent of three billion tons of CO₂ reduction or 176 percent of the CO₂ emissions. All of this is discussed at http://www.mcilvainecompany.com/SURS/subscriber/Default.htm

John Darrow, W.L. Gore, emphasized the consistent good performance of membranes for coal-fired boiler applications. He pointed out that efficiency is not a function of dust cake. This not only assures constant efficiency but also assures constant pressure drop.

Steve Boyd asked John about membrane cracking. Steve is a consultant with extensive experience in China and Hong Kong. John stated that membrane cracking can occur with time but has not been significant enough to affect guarantees. After the session, McIlvaine conversed further with Steve. He related that membrane activity in China is very high. Furthermore there are a number of membrane coaters. Prices relative to non-wovens are lower in China than elsewhere.

Jason Horn, Stock Equipment, and Jan Drotningsvik, Applied Plasma, discussed the ModuPower Switch Mode Power Supply manufactured by Applied Plasma and sold in the U.S. by Stock. The Crawford station of MidWest Generating installed two units in November. Advantages of this power supply are

• Modularity allows for ratings that meet the application and for failure tolerance.

• No insulator is needed at output or soldered connection to leak oil.

• Driver (comparable with converter) has liquid cooled cooling block vs. air cooled…. No fins to plug with ash.

• Transformer oil is cooled via liquid to liquid heat exchanger… No fins on HV tank either.

• Less complex topology.

• Capacity can be added/taken from each bus section as needed.

• Use of HV cable instead of bus duct and solid conductor allows power supplies to be located at grade.

Mike Beltran, Beltran, provided coverage of wet precipitators. The company has supplied a number of WESPs for a coal-fired boiler in Calcutta, India. WESPs installed on ore roasters in the mining industry are proving to be highly efficient on selenium and arsenic. These toxic metals pass through dry ESPs and fabric filters as a vapor, but they condense and are captured by WESPs. With the new MACT rules looming this performance on toxic metals will be of interest. Where highly corrosive atmospheres are encountered the shell can be constructed of FRP and the electrodes of high alloy steel.

The bios, abstracts and photos can be viewed as follows:

BIOS, PHOTOS, ABSTRACTS - JANUARY 7, 2010

The individual slides are located in our Particulate Decision Tree as follows:

John Darrow – W.L. Gore

Start

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Particulate Removal

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Physical

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Component Specification

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