Debra Pflughoeft-Hassett,1 Andrew Stewart,2
1 UND Energy & Environmental Research Center, Grand Forks, ND, 2 Power Products Engineering, Inc., Eden Prairie, MN, 3 NDSU Carrington Research Extension Center,
Livestock producers in
Keys to Success
The following are the cornerstones to the construction of a good feedlot surface with fly ash:
· Optimum soil type, clay or clay/loam, with minimal sand or gravel
· Uniform distribution of the fly ash within the soil blend
· Proper pulverization and thorough mixing of the fly ash with the material to be stabilized
· Adequate moisture content for maximum density and strength
· Final compaction within a time frame of approximately 2 hours
Steps for Placement and Use of Fly Ash in Livestock Facilities
Step 1 – Determine the Quantity of Fly Ash Required
A simple calculation of the site area and desired depth allow the user to determine the amount of fly ash needed.
Step 2 – Arrange for Ash Transport from the Power Plant
Participating power plants will provide contact and
price information. Bottom-dump grain
trucks were used effectively in the
The surface should be clean and soil loosened to an appropriate depth.
· Option 1: Spread the fly ash evenly over the loose soil in the desired location. Mix the fly ash and soil with a rototiller or disc, and compact the mixture to achieve the desired surface.
· Option 2: Mix soil and fly ash outside of livestock area in a windrow configuration preferably on a roadway. The soil–fly ash mixture can then be placed where needed with a loader bucket, box scraper, or other equipment and then compacted.
After placement and compaction, the stabilized surface should be maintained in a moist condition for approximately 5 days through periodic application of water. The site should not be used for an additional week to ensure peak performance of the surfaces.
Fly ash is intended for use in pens where animals are confined throughout the year. Run-off in containment ponds can be used for irrigation, and manure can be spread on cropland according to current nutrient management guidelines.
Fly Ash Placement and Use Considerations
Peak performance of soil/fly ash surfaces will be ensured by following the steps noted and careful attention to some additional considerations:
· Soil–fly ash blending and compaction will be most effective at moderate temperatures (50oF to 80oF). Based on field experience, it appears that cooler temperatures have an impact on soil blending and compaction characteristics of the mixture as well as on ash hydration. Effective stabilization of cohesive soils can be accomplished as long as the soil temperature is 0oC (32oF) or above and construction procedures (soil blending and compaction) are modified to achieve proper mixing and compaction of the stabilized surface.
· Fly ash is a light, fine, powdery substance, and it is best placed and blended with soil under low wind conditions. People working with fly ash should wear appropriate masks for breathing and eye protection to minimize irritation. Vehicles may require more frequent maintenance of air cleaners when working in a dusty environment.
Just recently, the North
Dakota Department of Health has determined that fly ash can be used in
livestock pens in
Where to Find More Information
A more detailed publication with photos describing the mixing, placement, and packing process is being prepared for distribution through the North Dakota Extension Service.
Fly Ash Contacts:
Mr. Dan Doschadis Ms. Darlene Eckert
ISG Resources, Inc. Otter Tail Power Company
4013 3rd Street South 215
EERC and the
· Otter Tail Power Company
· North Dakota Department of Health
Their involvement, contributions, and continued interest provided valuable support for the fly ash and soil feedlot characterization program and performance assessment.
This research was done with the support of the U.S. Department of Energy (DOE) National Energy Technology Laboratory Cooperative Agreement No. DE-FC26-98FT40321. However, any opinions, findings, conclusions, or recommendations expressed herein are those of the authors and do not necessarily reflect the views of DOE.