Reprinted, with permission, from the proceedings of: Mitigating Air Emissions From Animal Feeding Operations Conference.
This Technology is Applicable To:
Species: Dairy, Beef, Swine
Use Area: Manure Storage, Manure Treatment
Technology Category: Covers
Air Mitigated Pollutants: Methane, Hydrogen Sulfide, Volatile Organic Compounds (VOCs)
System Summary
Geosynthetic covers have been used for a number of years for the control of odors from liquid manure ponds. Current projects are concentrating on large biogas collection covers that require skilled installation and significant installation time. This paper introduces a new prefabricated impermeable manure containment cover that is designed to make smaller projects economical. The cover is adaptable for a number of manure storage applications including ponds with variable liquid levels (slurry storage) and ponds with constant liquid levels (biogas collection).
Applicability and Mitigating Mechanism
- Slurry storage cover is applicable to ponds where liquid levels vary such as swine
- Odor control accomplished by keeping gases in suspension in liquid
- Biogas collection cover used when liquid levels are constant and low solids
- Odor control achieved by drawing gases off and destroying them or using them
- New cover design is applicable to both constant level or varying level ponds
Limitations
- Cover for small to medium sized ponds usually up to about 20,000 m2 (5 acres)
- Difficult to combine liquid level changes with biogas collection under the cover
- Ice formation can trap and damage cover
- Agitation and pump-out equipment can damage cover
Cost
Cost of the cover would include the supply of the cover, the on-site welding, placement of floats or weights, installation, and filling of weight tubes. A gas collection pipe underneath the perimeter of the cover would be included. Anchor trench excavation and backfill are not included but an estimate of $2.50 to $3.00 per lineal foot is appropriate in most locations. The supply of equipment on site would be extra – typically a front-end loader would be available at most facilities and would be borrowed for the installation. Local labor would also be needed – typically 8 to 10 people for up to two days. Most projects will take two days to install but will require good weather for those two days (no precipitation and wind under 12 mph). Weather delays can incur standby charges. Other materials required to be supplied on site are a quantity of sand for making sandbags (wind safety) and a source of clean water to fill weight tubes (contaminated water is not suitable). Cost for the supply and installation of Layfield’s new slurry storage or biogas cover would be between $15.60 and $20.98 per square meter ($1.45 and $1.95 per square foot) of surface area depending on project specifics.
Authors
Andrew Mills, Layfield Environmental Systems
Point of Contact:
Andrew Mills, amills@layfieldgroup.com
The information provided here was developed for the conference Mitigating Air Emissions From Animal Feeding Operations Conference held in May 2008. To obtain updates, readers are encouraged to contact the author.
