Manure holds power potential
In the future, all the homes in Logan may be powered using manure.
It may sound a little odd, but John Harrison, principal investigator for the Integrated Facultative Pond, said it could be a possibility.
Harrison and a few students from Utah State University are working on a new process at the Agriculture Experiment Station to make waste from dairy farms reusable.
“We are basically working on how to extract profit out of manure,” Harrison said.
The project, called the Integrated Facultative Pond, involves a process of extracting the methane and carbon dioxide from cow manure and using it to power an electric generator. The bi-products of the process will also be usable in other ways, he said.
The current two-cow model of the ‘pond’ is a smaller model of the full-scale version being introduced on two dairies in central Utah.
The process basically consists of three distinct steps.
The first step begins with the waste from the cow-milking sheds being flushed with water down the drains into a 20-foot pit.
Over time, the solid waste sinks to the bottom of the pit while the lighter particles float upward. The bugs and bacteria in the pit, along with a lack of oxygen, help in the process of releasing the gases into a holding tank above the pit.
“The water moves so slowly in the pit that it takes about 40 days for this part to take place,” Harrison said.
Even though the methane and carbon dioxide are collected in holding tanks, there is still potential for pollution from the methane, he said. The next step in the process takes care of this.
Between the pit and the gas chamber is a 1,000-gallon water tank. The water tank is used for dispelling some of the methane by mixing it with oxygen.
This water is also a perfect breeding ground for Duck Weed, a macrophyte plant, which can be harvested and used as a vitamin supplement for the cows, Harrison said.
“The nice thing is that the plant is very high in protein and can be recycled by feeding it to the animals,” he said.
The final step in the process cleans up the waste even further. The water is then pumped into a second holding tank where algae spirolina are allowed to grow.
“The algae is high in omega 3 fatty acids,” Harrison said. “Those are the good low-protein acids that are beneficial to animals and humans.”
Just like Duck Weed, the algae can be harvested and either fed to the cows as a food supplement or to fish to be consumed later by humans, he said.
The project is just one of the ways the agriculture industry is trying to deal with waste better, Harrison said.
“We are always trying to make the system sustainable,” he said.
Harrison described sustainability as a triangle having three important aspects.
First, the system must be environmentally friendly. Next, it must be socially acceptable. And lastly, the system must be economically viable.
“Some people may bring ethics into it as well, but I figure you either have ethics or you don’t,” he said.
Brad Miller, a junior majoring in accounting, is one of the students helping with the project. He said he is excited to be a part of it because they are helping the environment in ways people don’t even know about.
“It is very possible that dairies will be able to use this in the future, and maybe even sell it,” Miller said.
One of the other benefits pointed out by Miller is that the final water product from the system can be used as fertilizer for the farm where the manure first came from. The potential for the system is outstanding.
“There are enough dairies in Cache Valley that the system could one day be used to power the whole city,” Harrison said.
This final goal is still many years away though.
-jacobomoon@cc.usu.edu
By Jacob Moon
Features Editor
In the future, all the homes in Logan may be powered using manure.
It may sound a little odd, but John Harrison, principal investigator for the Integrated Facultative Pond, said it could be a possibility.
Harrison and a few students from Utah State University are working on a new process at the Agriculture Experiment Station to make waste from dairy farms reusable.
“We are basically working on how to extract profit out of manure,” Harrison said.
The project, called the Integrated Facultative Pond, involves a process of extracting the methane and carbon dioxide from cow manure and using it to power an electric generator. The bi-products of the process will also be usable in other ways, he said.
The current two-cow model of the ‘pond’ is a smaller model of the full-scale version being introduced on two dairies in central Utah.
The process basically consists of three distinct steps.
The first step begins with the waste from the cow-milking sheds being flushed with water down the drains into a 20-foot pit.
Over time, the solid waste sinks to the bottom of the pit while the lighter particles float upward. The bugs and bacteria in the pit, along with a lack of oxygen, help in the process of releasing the gases into a holding tank above the pit.
“The water moves so slowly in the pit that it takes about 40 days for this part to take place,” Harrison said.
Even though the methane and carbon dioxide are collected in holding tanks, there is still potential for pollution from the methane, he said. The next step in the process takes care of this.
Between the pit and the gas chamber is a 1,000-gallon water tank. The water tank is used for dispelling some of the methane by mixing it with oxygen.
This water is also a perfect breeding ground for Duck Weed, a macrophyte plant, which can be harvested and used as a vitamin supplement for the cows, Harrison said.
“The nice thing is that the plant is very high in protein and can be recycled by feeding it to the animals,” he said.
The final step in the process cleans up the waste even further. The water is then pumped into a second holding tank where algae spirolina are allowed to grow.
“The algae is high in omega-3 fatty acids,” Harrison said. “Those are the good low-protein acids that are beneficial to animals and humans.”
Just like Duck Weed, the algae can be harvested and either fed to the cows as a food supplement or to fish to be consumed later by humans, he said.
The project is just one of the ways the agriculture industry is trying to deal with waste better, Harrison said.
“We are always trying to make the system sustainable,” he said.
Harrison described sustainability as a triangle having three important aspects.
First, the system must be environmentally friendly. Next, it must be socially acceptable. And lastly, the system must be economically viable.
“Some people may bring ethics into it as well, but I figure you either have ethics or you don’t,” he said.
Brad Miller, a junior majoring in accounting, is one of the students helping with the project. He said he is excited to be a part of it because they are helping the environment in ways people don’t even know about.
“It is very possible that dairies will be able to use this in the future, and maybe even sell it,” Miller said.
One of the other benefits pointed out by Miller is that the final water product from the system can be used as fertilizer for the farm where the manure first came from. The potential for the system is
outstanding.
“There are enough dairies in Cache Valley that the system could one day be used to power the whole city,” Harrison said.
This final goal is still many years away though.
-jacobomoon@cc.usu.edu