Beneficial Reuse and Recycling Options

Dairyland has been recycling over 80 percent of the fly ash from the Genoa plant and we will pursue opportunities to continue to recycle our coal combustion byproduct. We will continue to recycle as much bottom ash as possible and the majority of the fly ash captured in our precipitator. However, once the scrubber is installed to significantly reduce sulfur dioxide emissions, we may be recycling a smaller percentage of the coal combustion byproduct than we do today, due to the expansive characteristic of the sulfur containing material.

Dairyland will continue to evaluate reuse options, including possible future recycling of the material, as technologies develop and situations (such as reuse restrictions) may change. We also support financially the research and development into these technologies, and it is our sincere hope that additional options will become viable.

Beneficial Reuse Research

The American Coal Ash Association reports that in 2006, approximately 9 percent of dry scrubber material was beneficially reused. Of this 9 percent, mining applications represented by far the largest type of application. Other uses include concrete and concrete products, flowable fill, roadways, waste and soil stabilization, and agriculture. The University of North Dakota recently reviewed potential beneficial reuse options for scrubber material (EPRI, 2007). A copy of their review is available here (PDF). The review ranked the beneficial reuse options as follows:

Cementitious products (such as masonry, flowable fill, and synthetic aggregate)
Mining applications

Cement replacement in concrete
Engineering applications
Agriculture
Soil stabilization
Wet FGD sorbent

Binder material
Cement manufacture
Hazardous waste fixation
Marine applications
Mineral wool
Sulfuric acid production
Wallboard

The UND report concluded that technical, environmental, and economic evaluations will likely be needed before these materials can be successfully introduced into the markets identified.

Dairyland is and will continue to search for and evaluate potential beneficial reuse options focusing on the high and moderate potential options listed above. We are also financially supporting research to develop these reuse options into practical applications.