Technology Colombia , Antioquia, Thursday, October 31 of 2013, 11:29

UA-led research team develops plant-based biofuel

Researchers at the University of Antioquia have managed to produce biofuel from aquatic plants

UDEA/DICYT Most of Ayapel inhabitants derive their livelihood from hunting, fishing and agriculture. However, these resources are being drastically depleted as a result of overexploitation and deforestation. Also overfishing has led to a decline in populations of several species including shad, catfish and bocachico. Illegal gold mining and drop in rice prices due to free trade agreements are also problems affecting this region.


Ayapel swamp is part of the wetlands of La Mojana, a 500,000-hectare (1.2 million acres) savanna flooded by the Cauca, San Jorge and Magdalena rivers in rainy seasons.


For the past 10 years, UA researchers have conducted studies to develop socio-environmental projects intended to preserve ecosystems and improve the quality of life of the population, as this is an area where most of the population lives in poverty.


Corpoayapel, a private non-profit organization devoted to improve the quality of life for people living in extreme poverty, has also played an important role in developing this project.


“Over the past 10 years we have worked hand in hand with University of Antioquia researchers as they have been able to conduct reliable and rigorous environmental studies,” said Luz Alvarez, CEO of Corpoayapel.
Biologist Nestor Aguirre, PhD, and Fabio Velez, a sanitary engineer and doctoral candidate at the UA School of Engineering arrived in Ayapel in 2003. With the support of the UA Office of Extension and Outreach, they embarked on a project to produce biofuel from aquatic plants found in the Ayapel swamp, including Eichhornia heterosperma, Eichhornia azurea, and Eichhornia crassipes (aka water hyacinth), which is often considered as a highly problematic invasive species that reproduces and spreads rapidly causing navigation problems.


“Due to lack of electricity, firewood is the dominant source of energy in rural areas. In Ayapel, firewood is mainly obtained from sweet mangrove, a tree that plays a significant role in preserving ecosystems as it provides a natural barrier against floods and is also nursery for young fish. Uncontrolled mangrove removal can have harmful effects on the swamp ecosystem, therefore, this project seeks to provide sustainable and environmentally-friendly alternatives to mangrove-derived firewood,” said Fabio Velez.


Samples of different plant species were collected from 3 sites in the Ayapel swamp in order to determine their physicochemical properties. Researchers also studied how to reuse waste rice husk as an alternative to firewood and prevent water pollution caused by careless disposal of plant-based waste.


“This study allowed us to develop a sustainable method for producing quality plant-based biofuels,” Velez said.


Threats to the environment


Lab test results showed the presence of mercury in collected samples. Also a previous study showed mercury contamination in sediments of the Ayapel swamp as a result of illegal mining, which may pose big threat to the swamp's ecosystem.


“Further studies are needed to determine the impact of mercury on the food web of the ecosystem and whether it has affected the population”, Velez said.


Researchers built an ecofriendly oven made of materials able to withstand the highest temperatures, retains heat, produces little to no smoke, and can remove mercury from contaminated plants.


They also built a solar powered herb dryer that uses low-cost renewable energy sources. This device is used to dry plants before processing them into biofuel.


The project involved single mothers, social workers, teachers and students in the Ayapel community. Other projects currently being developed include growing Moringa, a tree native to Africa that can be used to purify water. Researches also developed a solar water disinfection method (SODIS), which consists of pouring contaminated water into plastic or glass bottles that are exposed to the sun for several hours to kill bacteria.


Also members of GAIA - a University of Antioquia research group dedicated to environmental modeling and management - placed monitoring equipment in the swamp to measure temperature, wind speed, humidity, solar radiation and precipitation levels and collect information on how these factors could be affected by climate change.