Proposta de produção e utilização de biopolímero para tratamento de água de lavagem de filtro de ETA por membranas de ultrafiltração

Abstract

Currently, numerous synthetic petrochemical-based polymers, as well as natural polymers obtained from renewable sources, are used as aids in flocculation, sedimentation, and filtration processes in Water Treatment Plants (WTPs). Unfortunately, these water treatment plants produce substantial effluents and waste, especially in sedimentation and filter washing units, where improper disposal is a recurring practice leading to significant environmental damage. This research aimed to produce and evaluate the biopolymer derived from mutamba fruit (Guazuma ulmifolia Lambert), using it as an aid in the flocculation and sedimentation processes. The analysis was conducted using water resulting from the filter washing at the Ultrafiltration Membrane Water Treatment Plant (UFWTP). The methodology involved producing the mutamba fruit biopolymer in powder form for preparing an aqueous solution. Additionally, extractions were performed using maceration and Soxhlet methods (cold and hot), with methanol and hexane as solvents. Physical and chemical characteristics such as turbidity, color, and pH of the raw water from the Cuiabá River and the UFWTP were analyzed, along with the development of coagulation diagram using the UFWTP sample. An evaluation of the biopolymer efficiency was also conducted by, comparing them with synthetic polymers, MCT A 4030 and Profloc A 1005, using ferric chloride as the primary coagulant through bench-scale tests (Jar test). Results were compared with effluent discharge regulations, specifically CONAMA Resolution 430/2011, and subjected to descriptive distribution statistical (Box Plot) and analysis of variance for p<0.05 (ANOVA), with a 95% significance level. During the study period, the raw water results from the Cuiabá River showed turbidity, color, and pH ranging between 18 - 130 NTU, 70 - 595 PCU, and 7,10 – 7,43, respectively. For the UFWTP, turbidity, color, and pH values ranged from 181 – 2.470 NTU, 880 – 16.600 PCU, and f 7.2 to 8.12. The diagrams revealed regions with optimal coagulation dosages and pH for removing turbidity and color in the UFWTP. Mutamba biopolymers demonstrated efficiency in removing turbidity and color, with values exceeding 95% and 99%, respectively, approaching those obtained with synthetic polymers. Regarding statistical analysis, the results were significant for turbidity data, with calculated F values of F (4;20) = 16.0796 and p = 5.0E-06; for color, F (4;20) = 34.3088 and p = 1.3E-8, and for pH, F(4;20) = 16.802 and p = 4.0E-6. The tests showed that the supernatant meets the requirements of CONAMA Resolution No. 430/2011. Based on the results obtained, it can be concluded that mutamba biopolymers constitute a new and innovative technological option derived from natural sources, demonstrating technical feasibility and environmental and human health advantages, making them potential alternative in water and effluent treatment.