“Dry vs. Wet Cooling” was the Hot Topic Hour on June 5, 2014

 

The webinar yesterday covered many issues relative to cooling condensed steam in power plants. It was conducted in a discussion mode with a few presentations to facilitate the discussions. Panelists included:

 

Alan Gaulke, AECOM

 

Jessica Shi, Ph.D. Senior Technical Leader/Manager Technology Innovation Research for Water Conservation, EPRI.

 

William (Bill) F. Harfst Consultant, Harfst and Associates, Inc.

 

Terry Dwyer, SPX Cooling Technologies, Inc.

 

Barbara Carney Chemical Engineer, Department of Energy, National Energy Technology Laboratory (NETL)

 

Andrew Howell, Senior Systems Chemist, Xcel Energy

 

Discussion Question 1.  Why a dedicated website just on Power Plant Cooling?  Bob McIlvaine briefly explained the dedicated Power Plant Cooling website.  http://www.mcilvainecompany.com/PwrPlntCoolAnalysis/Subscriber/Default.htm

It is one of a number of free sites on narrow subjects Continuous Analyses. The webinar today and future webinars on cooling will use this site to facilitate high level discussions and decision making.  One example in the Thursday webinar was a discussion of China. Jessica Shi of EPRI was the only U.S. attendee at a major cooling tower conference in Beijing. Her question was whether U.S. utilities would consider attending Chinese conferences.  Andrew Howell of Xcel Energy was recently in China.  He did not believe that most utilities in the U.S. would fund such trips. On the other hand, Kent Marten of SPX pointed out that his company is a major supplier of cooling towers in China. There are lots of Air Cooled Condenser (ACC) units on coal-fired power plants and few on combined cycle power plants.  A recent trend is toward the Heller type indirect cooling.

 

Discussion Question 2.  What are the options?  Terry Dwyer and Kent Marten of SPX started the ball rolling with an analysis of the options. We displayed the following from the website:

SPX Cooling Options

SPX offers the range of cooling options including dry, hybrid and wet. Energy and water usage are major considerations in selection.

One of the power points which was displayed compares water savings and energy use for various options.

 

SPX has now designed modular ACC systems. These systems reduce installation costs and time.

 

 

Discussion Question 3. What are some of the potential changes and improvements?  Jessica Shi of EPRI covered some the ongoing programs to advance dry cooling.

 

 

 

Discussion Question 4. What should we know about the impending water intake rules?  Alan Gaulke of AECOM highlighted some of the important aspects.

 

EPA Administrator McCarthy signed the final version of the rule implementing § 316(b) of the Clean Water Act on May 19, 2014, which will become effective 60 days after it is published in the Federal Register. The rule will affect existing cooling water intake structures at an estimated 544 electrical generating facilities and 509 manufacturing facilities and it made minor changes to the new facility rule that was published in 2001.

 

The owner or operator of an existing facility must comply with one of the alternatives in (c)(1) through (c)(7) below:

 

  1. Operate a closed-cycle recirculating system;
  2. Operate a cooling water intake structure that has a maximum through-screen design intake velocity of 0.5 feet per second;
  3. Operate a cooling water intake structure that has an actual maximum through-screen intake velocity of 0.5 feet per second;
  4. Operate an offshore velocity cap that is installed before the effective date of the rule;
  5. Operate an approved modified traveling screen;
  6. Operate any other combination of technologies, management practices, and operational measures that the permitting authority determines is the best technology available for impingement reduction; or
  7. Achieve the specified impingement mortality performance standard by monitoring fish mortality.

 

Discussion Question 5.  Are there CO2 considerations with various dry cooling and hybrid options?  Andy Howell summarized the situation by stating that while ACC reduces water use it increases energy consumption, reduces plant output, and increases CO2 emissions.

 

Discussion Question 6. What are the water quality issues? Bill Harfst indicated that with chemical additions the cooling tower cycles of concentration can be increased from the present 3-4 to as many as 10.  This greatly reduces water use. However, as Barbara Carney pointed out, the amount of solids discharged remains the same. Bill then pointed out that final filtration with cross flow membranes and then evaporation of slurries can eliminate any water discharges. The question is expense.

 

Discussion Question 7.  How will this effort be coordinated with ACC User Group, CTI, CCJ and other associations and publications?

§  One example is CCJ coverage of GEA.  Eric Fournier of GEA commented on the range of dry and wet cooling options available worldwide.

 

Barbara Carney of NETL pointed out that use of wastewater was an attractive option. NETL is funding a number of projects. Here are links to some of the reports.

 

Black and Veatch was scheduled to make a presentation but was unable to attend. McIlvaine displayed the following report on an installation using reclaimed water.

 

West County Energy Center (WCEC) Unit 3 is a world-class, combined cycle combustion turbine project. West County Power Partners, LLC, is managing the project for Florida Power & Light Company (FPL), and Black & Veatch has a major role in completing the engineering, procurement, construction and commissioning. With a nominal capacity of 1,250 MW, Unit 3 will contribute to FPL’s highly efficient power plant fleet, which serves more than 4.5 million customers in Florida.

 

Unit 3 includes three Mitsubishi G-Class combustion turbine generators exhausting into three Nooter/Eriksen heat recovery steam generators, and one Toshiba reheat condensing steam turbine generator, all purchased by FPL. Utilizing its global supply chain, Black & Veatch was responsible for purchasing all other engineered equipment. The unit will have the capability for dual fuel operation using either natural gas or fuel oil. 

FPL completed a project in October 2010 to provide reclaimed water from a local water treatment plant for cooling tower makeup for all three units. The previous source for makeup water was from Floridan aquifer deep wells. This project greatly reduces water used from the wells and increases sustainable practices by putting discharged water from the treatment plant to better use. 

The individual presentations are as follows:

Cooling Water Intake Structure Rules for Existing Facilities: Clean Water Act § 316(b) by Alan Gaulke, AECOM - Hot Topic Hour June 5, 2014

Alan Gaulke of AECOM highlighted some of the important aspects of cooling water intake structure rules.

Revision Date:  6/5/2014

Tags:  221112 - Fossil Fuel 化石燃料, AECOM, Cooling Tower, Air Cooled Condenser


EPRI Power Plant Cooling Technology Innovation Research Overview by Dr. Jessica Shi, EPRI - Hot Topic Hour June 5, 2014

Jessica Shi of EPRI covered some the ongoing programs to advance dry cooling.

Revision Date:  6/5/2014

Tags:  221112 - Fossil Fuel 化石燃料, EPRI, Cooling Tower, Air Cooled Condenser


Carbon Dioxide Emissions from Units with Air Cooled Condensers by Andrew Howell, Xcel Energy - Hot Topic Hour June 5, 2014

Are there CO2 considerations with various dry cooling and hybrid options? Andy Howell summarized the situation by stating that while ACC reduces water use it increases energy consumption, reduces plant output, and increases CO2 emissions.

Revision Date:  6/5/2014

Tags:  221112 - Fossil Fuel 化石燃料, Xcel Energy, Cooling Tower, Air Cooled Condenser


Practical Methods for Achieving Cooling Tower Water Savings by William Harfst, Harfst and Associates - Hot Topic Hour June 5, 2014

What are the water quality issues? Bill Harfst indicated that with chemical additions the cooling tower cycles of concentration can be increased from the present 3-4 to as many as 10. This greatly reduces water use.

Revision Date:  6/5/2014

Tags:  221112 - Fossil Fuel 化石燃料, Harfst and Associates, Cooling Tower, Air Cooled Condenser