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Anaerobic Digester, Organic Ag Online, “Feeding the World”

Posted by | April 21, 2010

Managing Dairy Waste for Profit

Biosystems engineer Shulin Chin and colleagues discuss the anaerobic digestor behind them.
Biosystems engineer Shulin Chin and colleagues discuss the anaerobic digestor behind them.

Researchers from a cross section of disciplines at Washington State University, along with USDA researchers, have teamed up to work on addressing a challenging issue within the dairy industry in the state of Washington: nutrient management.

Coming from the departments of animal sciences, economics, biological systems engineering and crop and soil sciences, the scientists are working together to curb the potential harm that dairy waste poses to the atmosphere as well as surface water in the form of runoff. Their multidisciplinary solution? An anaerobic digester that recycles waste and makes farmers money.

The digester, located near Monroe, Wash., is designed to take in waste from nearby dairy farms. Manure is pumped from the dairies in a six-inch, buried pipe so that none is transported by truck. Transporting the effluent by pipe significantly reduces the cost of the operation.

Through a process known as anaerobic digestion, animal manure can be transformed from its original state into three basic and potentially useful products. One of the co-products from the process is methane, which can be used in electrical power generation. A second co-product is a fibrous organic material that is a perfect soil conditioner for nursery plantings and home gardening. The third co-product is a slow-release, crystallized solid fertilizer called struvite that is rich in nutrients, including nitrogen and phosphorus.

Anaerobic digestion of manure produces methane. This highly combustible gas is burned, and the heat energy is used to run a generator. The generator creates electricity that is sold by Qualco to Puget Sound Energy. Joseph Harrison, a WSU professor of animal science and nutrient management specialist, said the income dairy farmers may receive from selling the energy is one of the benefits of the digester.

“Selling the energy is an immediate benefit for the dairy farmers to help supplement their income in a time when the cost of production within the dairy industry is so high,” said Harrison. “While it isn’t the ultimate answer to the financial problems the dairy farmers have, being able to sell the electricity while still having nutrients to go grow crops can help.”

Anaerobic digesters can cost millions of dollars to install, which may not be feasible for many dairy farms to construct. Shannon Neibergs, a professor of economic sciences at WSU, suggests that dairy farmers work together to construct a digester that would serve their region.

“If dairies were to share the costs associated with implementing a digester and all of them have the liquid waste flushed to it, it could potentially be economically feasible,” said Neibergs. “Of course, the percentage each individual dairy deposits into the digester they would get back the relative value in fertilizer.”

The digester operation is a joint venture between the Sno-King Alliance, Northwest Chinook Recovery, the Tulalip Indian Tribes and local dairy producers. The anaerobic digester has been funded by a zero interest loan. The research components with the digester are being funded by multiple grants, with a USDA conservation and innovation grant being one of the sizeable ones.

“Our goal with the anaerobic digester is to expand the number of dairies that are contributing to the operation,” said Neibergs. “It will also continue to serve as a research innovation and demonstration site.”

– by Ashley Scourey, Marketing, News, and Educational Communications intern

For more information on Biosystems Engineering at WSU, please visit

Organic Ag Online

Student Blair van Pelt with baby goat at Monteillet Fromagerie, a goat and sheep cheese making farm.
Student Blair van Pelt with baby goat at Monteillet Fromagerie, a goat and sheep cheese making farm.

Over spring break, 32 students in an online sustainable agriculture class got together in the Walla Walla Valley to learn about sustainable food systems.

WSU assistant research Professor Kevin Murphy led his Agriculture and Food Systems 445/545 class on the weeklong field trip. The class visited a winery, cider house, slaughterhouse, and an onion farm.
“We visited quite the variety of mills, food production centers, co-ops and farms,” Murphy said. “The farms we visited ranged in size from a couple acres to 40,000 acres.”

The purpose of the class is to explore food production techniques in the Walla Walla region and to understand how to apply sustainable agriculture methods, Murphy said.

“This field trip is the central element to the whole class,” he said. “You can learn a lot by reading and lecture, but you learn a lot more by actually visiting these farms and talking to the farmers about what they are doing.”

“It really did a great job of framing all the concepts we were learning about within the bigger picture,” student William Henderson said. “I really learned a lot.”

Students can now apply for summer and fall online organic agriculture classes. Internships, required to complete the organic agriculture certificate, are also available.

– By Kathryn R. Sullivan, CAHNRS Marketing and News intern

For more information about WSU’s online organic ag certificate program, please visit

Kidwell Wins Common Reading Award; “Feeding the World” to Air May 6 & 9

About 400 people came to hear what ag experts have to say about the future of farming.
About 400 people came to hear what ag experts have to say about the future of farming.

WSU Professor Kim Kidwell has earned the Common Reading Excellence Award from the WSU University College for her use of Michael Pollan’s “The Omnivore’s Dilemma” in Agricultural and Food Systems 101 class.

Kidwell, who also serves associate dean for academic programs in the College of Agricultural, Human, and Natural Resource Sciences, used the book as the basic framework for the course. She invited representatives from a variety of agriculture industries and academic disciplines to speak each week during fall semester 2009 and opened those sessions to the WSU community at large.

CAHNRS also created a “Food for Thought” Web site that included features such as interactive blog, an “Ag Word of the Week” and media coverage of agricultural and food-related issues as part of its participation in the Common Reading program. The college also worked with WSU Dining Services to place an “Ag Word of the Week” on in dining halls throughout the semester.

CAHNRS’ Common Reading activities culminated in January with “Feeding the World: A Washington Agriculture Community Conversation,” a panel discussion featuring industry leaders addressing some of the most pressing challenges facing agriculture locally and around the globe. KWSU-TV filmed that event, which attracted nearly 400 students, faculty, staff and members of the agriculture and food communities, for its “On Campus at WSU” series. It will air on Chanel 10 at 9 p.m., Thursday, May 6, and again at 10 a.m., Sunday, May 9.

Excerpts from the program are available for viewing at

Learn how ag industry experts responded to questions from students and members of the community at

Read Dean Dan Bernardo’s response to “Feed the World” on his blog at