By Ron Goble
LOS BANOS – A pilot project to clean up a dairy lagoon has been underway since June at a dairy just east of here. Verdure Technologies, Inc., (VTI) headquartered in Pocatello, Idaho has developed what they refer to as Micro-Gas Attendant (MGA).
What that means in plain English is that the system will remediate the waste and capture the greenhouse gases (GHG), which is eventually turned into pipeline quality methane gas for PG&E.
In the developmental stages for the past three years, Mark Terry, chief technical officer, and Douglas Brown, chief executive officer, of VTI are putting their cutting edge manure management system through a real life test on a normal sized California dairy.
The MGA produces microorganisms that consume volatile organic compounds and solid waste, explained Terry, former chief technology officer for Global Food Technologies. VTI’s proprietary technology uses local (onsite) nutrient to grow indigenous aerobic, facultative and anaerobic microorganisms and algae.
“VTI’s manure treatment system brings together advances in biology, chemistry, and the physical sciences to provide a practical solution for a host of environmental, and production efficiency challenges that have long defied the dairy industry,” said Terry.
“The MGA is a solar powered, geothermal regulated, remotely monitored automated system that was developed specifically to eradicate the high levels of waste, environmental pathogens, and volatile organic compounds produced by CAFOs,” explained Terry.
The pilot project is using a smaller runoff lagoon so they know the exact dimensions and determine the capacity to handle waste from a certain number of cows. While the dairy milks about 1,600 cows, this project will also allow them to determine how many incubators are need to handle a 4,000-cow dairy.
“We bypassed the solids separator and filled the lagoon up with waste from the flush lanes. We turned our MGA system on and over a 90-day period had JM Lord, an independent industrial laboratory in Fresno, do extensive testing,” said Brown. “We put a pump in the separator pit and installed a large irrigation pipe to disperse waste evenly throughout the lagoon and started replicating how many cows we could handle with the small system we built.”
Terry explained, VTI has a proprietary suite of hundreds of microorganisms that provides a continuous supply of what the lagoon needs at every depth. They pull nutrient into the incubators from the lagoon at every two feet in depth and the chemistry that goes into the incubator is different at every level and changes as the remediation process happens. The nutrient at the bottom of the incubator is from the bottom of the lagoon. Nutrient at the top of the incubator is from the top of the lagoon and every two feet in between.
Seven different levels are covered in the 14-foot deep lagoon. They replicate depth of the lagoon in two, 1,500-gallon incubators, so the same pressure is on the microorganisms from the time they start growing until they are released into the lagoon at the same level. That keeps the mortality rate for the organisms very low, said Terry.
“If there is a nutrient available to support a microorganism, it will start growing and multiply,” Terry declared. “Some thrive on phosphates, some on nitrates and there are millions upon millions of microorganisms being grown and released into the lagoon on a continuous basis.”
The top aerobic layer requires oxygen for the microorganisms to live. The middle of the lagoon is facultative, which means microorganisms can live with or without oxygen. The bottom is anaerobic and those microorganisms would die in the presence of oxygen. So they grow three types of microorganisms for the lagoon.
The project also includes an algae component in order to capture the greenhouse gases (GHG). They grow two types:
“We capture the biomass at the bottom of the lagoon and whatever trace gases are generated from that – methane, carbon dioxide, hydrogen sulfide – is then pumped over into two different types of algae growth colonies – algae that requires UV light and algae that doesn’t require UV light. Algae lives on the gas and will determine which algae is needed.
“We grow chemotropic algae and inject it into the bottom layer of the lagoon and the phototropic algae into the top layer to reduce the greenhouse gases,” said Brown. “The algae will actually envelop the gas and die and then microorganisms convert that to a real rich biomass at the bottom. So we will pull that biomass out and gas it off and create clean natural gas.”
VTI is working with PG&E and once the revenues from the natural gas has covered the cost of the MGA, they will begin sharing the revenues with the dairy producer. “We are addressing the renewable energy and the environmental sides of the dairy waste management issue and are actively looking for other dairies interested in participating in future projects,” Brown added.
JM Lord, Inc. has determined through its extensive testing of the lagoon that the system has performed efficiently enough to:
• Reduce total salts 53%
• Reduced ammonium levels 26%
• Reduced sulfates 97%
• Reduced phosphates 95%
• Reduced nitrates 96%
• Reduced suspended solids 89%
• Reduced BOD 87% and significantly reduced odor.
With the test results Terry and Brown believe that dairymen could add additional cows on that dairy without requiring additional acreage to support it.
Terry said that the dairy with their system will be flushing with lagoon water full of microorganisms so that those organisms will also begin cleaning the organic matter in lanes as well.
Terry has been working with researchers at Idaho State University on some of the science required in the system. All their patents are pending for what they call the Biogas Energy Conversion System. Brown said the patents will protect them from competition trying to duplicate the system they engineered, which enables them to grow microorganisms on site with indigenous nutrients.
Transfer pumps inject microorganisms into the incubators and the entire system is computerized and can be operated remotely. The system will signal changes in volume or drop in microorganism activity and can be adjusted and/or rebooted by computer from any remote location.
The system is a plus for the environment because it gets rid of numerous toxic chemicals. This lagoon management system can work without a solids separator and all the equipment that that entails, said Brown. And the sale of gas will be a boost to the bottom line for the dairy producers.
Terry said they did early bench testing in their lab and on a small 200-cow dairy in Idaho before setting up the full blown pilot project on the Calirornia dairy, which represents larger dairy operations in the West.
“I probably learned more about the realities on a large commercial dairy during this pilot project than anything else,” Terry said. “I had no idea how many plastic gloves, syringe caps, Styrofoam cups, bottles, twine and other garbage can come in with the manure. It affected how we designed everything. We worked with a company to develop a new pump, which is called the disintegrator pump. It reduces everything to an 1/8-inch so the lagoon system can handle it.
“We told the dairyman not to worry about trying to find a way to keep those kinds of foreign objects out of the manure. We would learn how best to deal with it and make it work. That’s the real world,” Terry said.
■ To contact Mark Terry, Verdure Technologies, Inc., e-mail email@example.com or call 208-251-2506.
■ To contact Douglas Brown, e-mail firstname.lastname@example.org or call 678-779-5757.