Not all manure is conveyed equally, so to speak, because not all manure is subjected to the same environmental conditions after being “deposited” on the alley floor. One of those conditions is bedding, especially where sand bedding is concerned.

Whereas non-sand-laden manure can be conveyed using gravity flow in large-diameter, flat pipes or stirred up and pumped long distances using centrifugal pumps, sand-laden manure cannot reliably over the long term.

Several factors go into selecting a manure conveyance system – for example, site topography, building layout, climate and management style. And there’s more. What will be the ultimate fate of the manure – manure storage, digester, irrigation, etc.?

At the time they were milking 285 cows at Oregon Dairy Farm LLC, located in an urban area. Therefore, the odor mitigation provided by digesters was another main reason they embarked on the project.

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According to the U.S. EPA’s AgSTAR program, anaerobic digesters are technically feasible at more than 2,600 U.S. dairy operations, but many early adopters of methane digester systems find they are not supported by the current market conditions and energy policies.

During a seminar at World Ag Expo, three speakers explained why dairy farms are uniquely positioned to benefit from the growing anaerobic digester industry.

“You almost can’t read anything without seeing something about climate change and water use,” said Dr. Jude Capper, Washington State University. “The anti-animal ag industries really try to get people’s attention. HSUS, PETA, Greenpeace know exactly what messages to put out there.”

In Capper’s presentation last month at the Vita Plus Dairy Summit in Wisconsin Dells, Wisconsin, she said the Environmental Working Group (EWG) released a report in July that displayed meat to be the food with the highest carbon footprint.

Sources of ammonia
Ammonia emissions into the atmosphere occur primarily from livestock buildings, open feedlots, manure storage facilities, during manure handling and treatment, and when manure is applied on land.

Livestock production and fertilizer application are identified as major sources of atmospheric ammonia emissions.

The group of 10 dairy farms near Fair Oaks, Indiana, will soon go a step further by using biogas from its anaerobic digesters to power a fleet of milk trucks.

It went something like “… and by the way, when are you New Yorkers going to stop spreading manure in the winter?” Being an agronomist, the can of worms was immediately opened wide.