Uso de microalgas no tratamento de efluentes da indústria sucroalcooleira

Abstract

Microalgae are aquatic microorganisms capable of generating abundant biomass with different molecules, through the transformation of carbon dioxide and light contained in the atmosphere, in addition to the nutrients present in water. The synthesis of nutraceutical compounds, specifically polyunsaturated fatty acids, as well as biofuels such as hydrogen and ethanol, is also a skill that microalgae have. Besides, given their metabolic versatility, these microorganisms are capable of remediation of industrial effluents with a high contribution of organic and inorganic components. Within the sugar and alcohol industry, vinasse is known to be one of the effluents that have a high level of toxicity in its composition, so several treatment methods are studied to avoid its improper disposal, focusing on the preservation of nature. Thus, this course conclusion work aims to analyze the efficiency of the use of microalgae, specifically the one called Chlorella vulgaris, in the treatment of effluent from the sugar and alcohol industry, namely vinasse, through a comparative study between scientific articles with another photo fermentative system. The exposed studies were: case study 1 (microalgae-bacteria reactor) and case study 2 (application of the tannin coagulant). Comparing their results, we concluded that both can reduce the toxicity content of vinasse, with the highlight of case study 2 with high color removals (96%) and turbidity (98%), however, if dealing with the COD parameter (Chemical Oxygen Demand), case study 1 that uses the microalgae Chlorella vulgaris proved to be extremely effective in its removal, showing 78.6% and the other study reaching only 36%, therefore becoming the most appropriate method. Also, the system that used the microalgae produced 4.1 mg / L d of microalgal biomass at the end, which can be used in the manufacture of biofuels, collaborating directly with sustainable development.