Environmental Evaluation of Agar Production from Macroalgae Gracilaria sp.

Abstract

Agar is a polysaccharide that is extracted from algae of the Rhodophyta class, better known as red algae. Since the discovery of agar extraction, an attempt has been made to optimize this process in order to obtain a high-quality product that produces less negative environmental impacts and is economically profitable. In the present study, the environmental analysis of the agar production process was carried out from red macroalgae of the genus Gracilaria sp. For which, the WAR algorithm or Waste Reduction algorithm was used by the implementation of the WARGUI software and Microsoft Excel. Initially, the environmental impact assessment was carried out in which different categories were evaluated to determine the total environmental impact potential generated by the process. Subsequently, we analyzed both the flow of toxicological and atmospheric environmental impacts generated by the limits of the system, as well as those generated by the total process chemistry. Finally, we compared the variation of the total environmental impacts generated after the change of the energy source. Results shows that the highest environmental impacts are generated when the energy consumed by the process is included in the evaluation. The highest atmospheric impacts value obtained was 107 PEI/hr, as well as the toxicological impacts, the highest value of PEI generated was 118 PEI/hr, which is low compared to other processes. In addition, in the analysis of the effect of energy source, the highest impact was 17.7 PEI/hr and when the gas is used as an energy source, the total environmental impacts were reduced by 16%.