Researchers hope to impact farms in Nicaragua

Eric Debner

Researchers from ISU-based Biorenewables Research Laboratory are teaming up with ISU alumni in a project that will bring biochar to Nicaraguan farmers.

Two graduate research assistants in mechanical engineering, Bernardo Del Campo and Matthew Kieffer, are working in collaboration with Emerging Opportunities for Sustainability International, a nonprofit organization founded by a group of ISU alumni, to design and build a pyrolysis reactor that can produce biochar efficiently and at low cost for rural Nicaraguan communities.

In summer 2013, Del Campo will travel to Nicaragua, where he will be assisted by Wesley Meier, ISU alumnus and international director of Emerging Opportunities for Sustainability International, and other members of the project team to build the pyrolysis reactor and research the effects biochar has on local agricultural production.

Gregory McGrath, ISU alumnus and executive director of Emerging Opportunities for Sustainability International, said the goal of the project is to help produce and implement biochar together with conventional fertilizers to improve crop yields on Nicaraguan farms.

“We want to help farmers improve their [crop] yields with a source of low cost fertilizers,” McGrath said. “The role of [Emerging Opportunities for Sustainability International will be] to provide on-the-ground resources and support for [Del Campo] to help him successfully build biochar equipment and implement the technology into small farms.”

Biochar is a black, coal-like substance produced as a byproduct through a process called pyrolysis. This process heats biomass such as corn stover and switchgrass to extreme temperatures in the absence of heat. Del Campo said biochar has beneficial nutrient properties that make it applicable as a soil amendment in farming, gardening and other botanical practices.

Biochar has the opportunity to increase crop yields if applied as a fertilizer, said Meier. It also presents an opportunity to improve the environment by sequestering carbon dioxide from the atmosphere.

“The whole idea of biochar is putting carbon back into the soil, but in a useful way,” Del Campo said.

Del Campo said the first task on the project list is to design a pyrolyzer which can produce a reasonable amount of biochar at low cost. Building pyrolysis reactors to produce biochar is expensive. Del Campo said the pyrolysis reactors in the Biorenewables Research Laboratory required upwards of $250,000 to build; the Nicaragua project team has around $5,000.

The pyrolysis reactor design is still in the developmental stages, but Kieffer said there are a few key components that will be included in the final design which consists of a 55-gallon steel drum that will serve as the reactor, a stand to elevate the reactor above the heating source, and a cover that will prevent heat from escaping the system and will also help in drying the biomass before it is put inside the reactor.

“The next challenge is to utilize the heating source as efficiently as possible with as little energy as possible,” Kieffer said. “Our goal is to utilize a simple method to produce biochar that’s cheap and efficient.”

Building pyrolysis reactors at low cost can come with a number of problems, Del Campo said. Using low-cost materials raises concerns over the safety and quality of the biochar production.

Del Campo said smoke emissions from the reactor is an issue that requires an additional design element to buffer any health risks and environmental safety concerns. Producing quality biochar requires Del Campo to look at a number of variables, such as temperature and biomass feedstock type.

“I work on the quality of the biochar,” Del Campo said. “I make sure the temperature output of the reactor and the quality of the biochar is balanced. That’s my contribution.”

Del Campo said he hopes this project will attract many students from every disciplinary background, such as economics, sustainability science, and social science to help contribute to the overall effectiveness of the project.

“You could create the most beautiful reactor, but it’s not cost-competitive, or you make [quality] biochar, but the people don’t like it or don’t know how to use it,” Del Campo said. “If we do this project and encourage more [students] to come over and see what they can contribute, then there will be more people working on it.”