Wet vs. Dry FGD Will be the Subject of the Hot Topic Hour on Nov. 12, 2009
The latest forecast of the McIlvaine Company in World FGD Markets projects that over the next 12 years owners of coal-fired power plants will spend $200 billion dollars to add FGD systems to existing and new combustion units. The market will be strengthened due to the need to remove mercury and HCl as well as SO2. Scrubbers remove all three contaminants. The need for multi-pollutant control will shape the decisions as to which type of scrubber will be selected. Dry scrubbers are better at removing SO3. Wet scrubbers are cost-effective in removing mercury chloride and HCl. They will also remove more selenium. On the other hand, dry scrubbers will remove more arsenic, lead, and other particulate metals.
A new MACT standard is looming. An indicator of the severity is the newly proposed standard for cement kilns which limits HCl to just 2 ppm. Can dry scrubbers meet this requirement? How many spray levels do you need in a wet spray tower to meet 2 ppm HCl?
The following speakers will discuss the relative merits of each type of scrubber, the impact of fuel composition on scrubber performance, provide details on the latest technology being developed or tested and describe the performance of wet and dry scrubbers that have been proven in the field.
Terence R. Ake, Product Manager for Turbosorp® Circulating Dry Scrubbers at Babcock Power, Inc. After the U.S. Supreme Court remanded the Clean Air Interstate Rule (CAIR) in December 2008, the U.S. Environmental Protection Agency (EPA) started developing new rules for deep cuts in sulfur dioxide (SO2) emissions from coal-fired power stations. The EPA told the Court that it would take two years to issue the new rules. In an action closely related to CAIR, the EPA will also impose the first ever federal requirements for coal power stations to reduce mercury emissions. While new rules are being written, there is a brief opportunity for a power utility to plan emissions controls for their power stations. There are two distinct options for scrubbing SO2: wet versus dry. The choice of scrubbing technology depends on whether the boiler is new, or the age of the boiler, the space constraints, the availability of water and other site specific facts. It is also important to consider the use of the byproduct. The co-benefits of a technology to remove sulfur trioxide, mercury and flyash may become important to answer the question of whether a boiler can be built or must be retired.
Greg Carleton, President of Pollution Control Services, Inc. will focus on the basic differences in the affect wet and dry FGD control have on the operating parameters for existing coal-fired generators. He will explain how numerous boiler modifications and fuel supply changes can either positively or negatively affect plant operational costs with both technologies. He will also discuss how the two basic technologies compare over the equipment life cycle in regards O&M cost.
Gordon Maller, Manager, Projects, URS Corp. In addition to being capable of obtaining higher SO2 removal efficiencies, wet FGD processes offer a significant secondary benefit as a result of their ability to also remove other pollutants such as oxidized mercury, particulate and other toxic metals. These secondary benefits will be discussed and data will be presented indicating the removal levels that have been reported in this presentation.
Pete Honeycutt, Manager, Air Quality Control Systems, Kiewit Power Constructors. Dry scrubbers have typically been limited to 95% SO2 removal. There is an emerging dry scrubber technology that can achieve 98% SO2 removal at reasonable lime stoichiometric rates.
Bob Nicolo, Hitachi Power Systems America. Our presentation will give an overview of the general differences in designs and performance of wet vs. dry FGD systems. We will cover the relative merits of each type of technology and multi-pollutant control variances. Hitachi is a provider of high performance wet FGD systems and can discuss the advantages of the high SO2 reduction capability for future CO2 readiness.
Roosevelt Huggins, Associate Vice-President, Black & Veatch Energy
To register for the “Hot Topic Hour” on Thursday, Nov. 12, 2009 at 10:00 a.m. CST (Chicago time), click on: http://www.mcilvainecompany.com/brochures/FGDnetoppbroch/Default1.htm.
Bob McIlvaine
President
847 784 0012 ext 112
rmcilvaine@mcilvainecompany.com