“Update on Coal Ash and CCR Issues, Standards and Solutions” Hot Topic Hour” on October 3, 2013

Five speakers with more than 100 years experience dealing with coal residuals provided lots of nuggets of knowledge yesterday.

Ron Grabowski, Vice-president Business Development at Clyde Bergemann Power Group Americas, Inc., Materials Handling Product Division, discussed the handling of bottom ash. 

He explained all the options including one which eliminates the use of any water.

1. Divert the flow of the existing bottom ash slurry piping to new dewatering bins.
2. Divert the flow of the existing bottom ash slurry piping to a remote submerged scraper conveyor (RSSC) system (ASHCON™).
3. Replace the bottom ash hopper system with a submerged scraper conveyor (SSC).
4. Replace the bottom ash hopper system with a dry ash conveyor (DRYCON™).

The depiction, advantages and disadvantages of the dry ash conveyor are shown below.

Dale Timmons, R.G., Business Development Program Manager at NAES Corporation, discussed the Circumix Dense Slurry System (DSS) technology. NAES Corporation and GEA EGI have teamed to deploy DSS technology in North America. DSS is a proven and commercially deployed technology that uses wastewater (including FGD water) to stabilize ash products.

Advantages pursuant to Effluent Limitations Guidelines (ELG) proposed rule include:

Ø  Effective Combined Stabilization of Ash & Wastewater

Ø  80%-90% Reduction of Water Use for Ash Management

Ø  Zero Discharge of Transport Water

Ø  Leachate can be Reprocessed = Zero Discharge Impoundment

Ø  Reduction of Plant-Wide Wastewater Generation

Ø  Enhanced Protection of Ground Water from Low Hydraulic Conductivity

Ø  Low Hydraulic Conductivity = Low Leachate Volumes

Ø  Proven Technology, Low Complexity, Low Life-Cycle Cost, Ability to Utilize Existing Infrastructure, Energy Efficient, Can Achieve Effluent Standards.

There is experience at Jacksonville Electric Authority (JEA) in the U.S. where the end product is being sold. There are many units elsewhere.

Bob McIlvaine suggested that the technology should be considered in conjunction with natural or inhibited oxidation FGD using magnesium enhanced lime. Where the gypsum end product cannot be profitably sold, there is money to be saved by eliminating the larger capital expense of forced oxidation.

Douglas J. Dahlberg PE, Project Associate II at Sargent & Lundy LLC, anticipates a final rule to classify CCRs under Subtitle D, Resource Conservation and Recovery Act (RCRA), similar to Municipal Waste.  The June 7, 2013 Code of Federal Regulations, Effluent Limitations Guidelines (ELG) and Standards for the Steam Electric Power Generating Point Source Category Proposed Rule stated:  “reliance on (current) data… coupled with the ELG proposed requirements could provide strong support for a conclusion that regulation of CCR disposal under Subtitle D would be adequate.”  Speculation on final regulation publishing timing ranges from October 2013 to the end of 2014.

The critical question for a power plant is “How do you transition your current disposal operation with minimum impacts and expense?”  Timely budget planning, decisions and actions are necessary to ensure a smooth transition. Whether your current disposal operation is wet or dry bottom/flyash/FGD byproducts, above or below grade, permanent disposal or transfer, your basic choices include:

• Close and cap your current disposal operation
• Transition the existing site to comply with new requirements
• Develop a separate new compliant disposal facility.  Regardless of whether your existing disposal site is lined, monitored or impacts groundwater, the best option may be to combine the disposal options.

Doug made a convincing argument that you can maximize the use of your existing site by depositing the new waste over the one which has already been covered and capped. In fact, one ultimate use will be as a golf course or sledding hill.

Bill Betke and Steven Mayes, GSE Environmental Lining and Technologies, stated GSE offers geosynthetic alternatives to compacted clay and earthen filter/drainage materials that are more effective and more economical to install. These materials enable longer life disposal facilities because they take up a fraction of the open space compared to compacted clay and earthen materials. Well-engineered systems are designed to minimize uncontrolled leachate leakage; thereby minimizing the risk of environmental damage.

Bios, Abstracts and Photos can be seen at: BIOS, ABSTRACTS, PHOTOS - 10-3-13.htm

The individual presentations are as follows:

• Coal Ash and CCR Issues and Standards Webinar - Hot Topic Hour October 3, 2013  (Webinar Recording  Dated:  10/3/2013)

• Technologies Available for Wet to Dry Bottom Ash Conversions by Ron Grabowski, Clyde Bergemann - Hot Topic Hour October 3, 2013  (Presentation  Dated:  10/3/2013)

• Coal Ash / CCR Issues, Standards and Solutions by William Betke and Steven Mayes, GSE Environmental - Hot Topic Hour October 3, 2013  (Presentation  Dated:  10/3/2013)

• Proposed / Final U.S. EPA Rule Coal Combustion Residuals by Douglas Dahlberg, Sargent and Lundy - Hot Topic Hour October 3, 2013  (Presentation  Dated:  10/3/2013)

• CCR -- ELG Proposed EPA Regulations Changing the Coal Power Generation Industry by Dale Timmons, NAES - Hot Topic Hour October 3, 2013  (Presentation  Dated:  10/3/2013)