Bioenergetic valorization of <i>Sargassum fluitans</i> in the Mexican Caribbean: The determination of the calorific value and washing mechanism

Abstract

<abstract> <p>The advent of large volumes of <italic>Sargassum sp</italic>. on the Mexican Caribbean coast has become an emerging issue for the Mexican population. The most frequent action is harvesting, but a correct treatment or energy recovery strategy is still missing. This work aimed to evaluate the energy potential of <italic>Sargassum fluitans</italic>, through elemental calculations and direct measurements, considering the effect of its washing. The calorific value determined by the direct method was 9.24 ± 0.28 MJ/kg and 12.64 ± 0.18 MJ/kg for dirty and washed <italic>Sargassum</italic>, respectively. The washing effect increased the calorific values in <italic>Sargassum fluitans</italic> by 36.80%. The washing effect increased the calorific values determined by indirect methods, increasing 10.10% and 41.04%, each method, respectively. The content of toxic metals was lower in both materials than that established for non-woody biomass from energy use, concerning the ISO 17225:2014 standard. The unit energy cost of <italic>Sargassum fluitans</italic> is ＄0.007 and ＄0.011 per MJ for dirty and washed conditions, respectively. Finally, the results of this work indicate that the <italic>Sargassum</italic> wash provides better characteristics to be considered an alternative fuel option in combustion systems such as thermo-electric plants (based on carbon), sugar mills, and cement kilns with co-processing of solid waste. Attending from a bioenergetic approach, <italic>Sargassum's</italic> emerging seasonal problem affects the Mexican Caribbean coast.</p> </abstract>