Does Lime Have Advantages Over Limestone? – “Hot Topic Hour” On August 30

On August 30 we will be reviewing the options of lime vs. limestone as FGD reagents for wet scrubber systems.  Very few operators have selected lime as the reagent for the latest wave of wet scrubbing systems.  The perception was that the capital cost savings were not offset by the perceived higher reagent cost and potential uncertainty of supply.

However, over the last several years the capital cost of limestone scrubbing systems has nearly doubled.  If in fact lime scrubbing systems can be installed for 70 percent of the capital cost of limestone scrubbers, the savings would now be $60/kW instead of $30/kW.

There is another good subject for discussion.  Can you install a lime system quicker than a limestone system?  There are delays on ball mills and big pumps associated with limestone systems but not lime systems.  There is less steel and less construction labor required.  So this is a good argument for lime.

On the other hand, lime has been in tight supply.  Will there be an ample supply available when needed?  This is an argument for limestone.

Another important issue is gypsum quality.  How important is it to have the whiter, purer lime gypsum?

There are some third alternatives as well.  For example, by pulverizing the limestone regionally you eliminate the need for ball mills at the FGD site.

Finally we have the efficiency issue.  Is there going to be a time when you wish you could achieve 99 percent efficiency?  The greater the efficiency requirement the more attractive is lime.  On the other hand, can you achieve the same result with organic additives and limestone?

We will be hearing from the experts on these subjects on August 30 at 9:00 a.m. CDT.  For more information on this and other “Hot Topic Hours, click on:  http://www.mcilvainecompany.com/brochures/FGDnetoppbroch/Default1.htm .

Bob McIlvaine

847-784-0012

rmcilvaine@mcilvainecompany.com