BIOREMEDIATION OF EFFLUENTS FROM THE HOUSEHOLD APPLIANCE INDUSTRY USING Scenedesmus sp.: BIOMASS RECOVERY AND NUTRIENT REMOVAL

The search for renewable energy sources highlights the use of microalgae, unicellular and photosynthetic organisms. Microalgae are used in wastewater treatment due to their ability to remove compounds and nutrients. Therefore, the present study aimed to evaluate the capacity of the microalgae Scenedesmus sp. in the bioremediation of industrial effluent from household appliances and the production of biomass resulting from this process. The microalgae Scenedesmus sp. were inoculated in carboys at a ratio of 1:4. Seven treatments were established, and the experiment was conducted over a period of 28 days. Microalgae population growth was monitored daily by cell density (DC) and by determining optical density. pH was analyzed weekly. The results showed that Scenedesmus sp. maintained in biological effluent promoted greater water pH variation (from 7.3 to 9.2) and removed nutrients, with complete elimination of ammonia in biological and mixed effluents, and removal of 83.3% manganese in the mixture. Maximum cell density reached 1.57 × 10⁷ cells. mL- and biomass recovery reached 0.7 g L⁻¹ in the mixed effluent, almost double the yield obtained in the synthetic medium f/2. These results indicate that effluents of the appliance industry are promising substrates for sustainable biomass and bioremediation production.