Abstract

MANCIPE-ARIAS, Lina Marcela  and  TRIVINO-RESTREPO, María del Pilar. Evaluation of sludge of wastewater treatment plant (WWTP) as raw material for the extraction of lipids in the production of biodiesel. Rev. ion [online]. 2018, vol.31, n.1, pp.71-79. ISSN 0120-100X.  https://doi.org/10.18273/revion.v31n1-2018012.

This research we evaluated the potential for use of sewage sludge as a raw material in the production of biodiesel. Sludge coming from the Wastewater Treatment Plant (WWTP) were selected from Sotaquirá (Boyacá, Colombia) and the total solid content was determined (TS), volatile solids (VS), heavy metals concentration, chemical composition, mmorphology and microstructure of the sludge. Extraction of lipids and fatty acids was carried out by the Soxhlet method according to Standard Methods 5520E with some modifications, using as solvents n-hexane and methanol, under two extraction times between 4 and 2.5 hours. Data obtained showed according to the sludge, that volatile solids are high, which confirms an important organic matter content. The yields on lipid extraction on dry basis with n-hexane and methanol were 33 and 28% at 4 hours, greater than at 2.5 hours at 19 and 17% respectively, indicating that time is a significant variable in the extraction percentage. The values presented by the acid indexes of the extracts were 215% and 208%, it means that the extracted fat contains a high amount of free fatty acids that will be transformed into biodiesel by means of esterification. With the obtained results, the sludge from domestic wastewater treatment plants represent alternative raw material for the extraction of lipids and free fatty acids in the production of biodiesel.

Keywords : sludge from WWTP; extraction; free fatty acids; heavy metals; lipids; biodiesel.

        · abstract in Spanish | Portuguese     · text in Spanish     · Spanish ( pdf )