Coffee dregs could produce biodiesel
A Universidad Nacional de Colombia (UNal) foreign student intern has obtained oil yields of 17% from coffee dregs from university cafeteria and household coffee brewing.Palmira, 25 de noviembre de 2015 — Agencia de Noticias UN-
The student has carried out the first stage of the project with coffee residue from the university cafeteria.
This was obtained by Brazilian researcher and Chemistry student Mario Rodrigues Cortes and published in an undergraduate project entitled, “Determination of methods to obtain biodiesel from coffee waste”, directed by Professors Judith Rodríguez, Hugo Martínez and Juan Carlos Clavijo.
To reach this coffee dregs potential preliminary result, Rodrigues carried out the first part of the project which consisted of collecting the material (22 kg.) of residue from the university cafeteria.
Coffee dregs are usually used as fuel for water boilers but seeing the energy potential as biodiesel, given its oil content (between 17 and 20%) Rodrigues hopes to produce an exploitable energy resource in just a few weeks.
Therefore the dregs were dried in several UNal-Palmira laboratories at 50 °C (122° F) for 48 horas; afterwards they extracted the oil with 96% ethanol at 60 °C (140° F) and stirring at 600 RPM.
He also experimented with two test trials with different ethanol concentrations and dregs and two different time intervals (1 and 2 hours) in which the 1:6 dreg and ethanol relationship provided the best oil yield at a rate of 17%.
“It is essential to exploit coffee dregs efficiently which has an important organic matter load and could be feeding grounds for fungi, which could alter soil properties,” said Rodrigues.
Rodrigues comes from the Instituto Federal de Educação, Ciência e Tecnologia de Rondônia in Brazil and is one of seven foreign students currently at UNal-Palmira thanks to the UNal international mobility program.
With this project Rodrigues hopes to positively impact the environment affected by intensive coffee production which is also a cause for deforestation, use of great amounts of water and above all that 80% of coffee fruit is considered waste with little or no economic value. This waste frequently pollutes water sources, producing foul odors and low oxygen availability which added to the amount of solids in the water impact human and animal water consumption.
According to statistics of the Agricultural-Livestock Sector Strategic Communication and Information Network (Agronet, for its Spanish acronym) during 2013 the Province of Valle del Cauca was the sixth most coffee producer in Colombia with a crop of 44,122 tons in 53,481 hectares (132,154 acres) with a participation of 6.76% of the total Colombian coffee production.
“The novelty of this project is to make brewed coffee dregs biomass (organic residual matter) known as a possible source for biodiesel,” added Professor Rodríguez.(Por: Fin/HAA/MLA/CA