Physicochemical characterization and evaluation of PGA bioflocculant in coagulation-flocculation and sedimentation processes

Autor(es)

Campos, Valquiria ; Fernandes, Ana R. A. C. ; Medeiros, Thales. A. M. ; Andrade, Erik L.

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING; v. 4, n. 4, p. 8-pg., 2016-12-01.

Resumo

This paper analyzesanalyses the effectiveness of three commercial products: aluminum sulfate, aluminum polychloride and polyglutamic acid-based bioflocculant, in water clarification and purification. Poly-gamma-glutamic acid (PGA), a naturally occurring anionic polymer, is already produced on an industrial scale. A conventional jar test apparatus was used for flocculation experiments. The tests were performed using raw water from the Salto de Pirapora Water Treatment Plant (WTP) in the state of Sao Paulo, Brazil. The structure and elemental composition of PGA bioflocculant, which was characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray fluorescence spectrometry (XRF) and thermogravimetric analysis (TGA), suggests that it is basically inorganic in nature, with high contents of calcium sulfate (87%) and gamma-polyglutamic acid (5%), among other chemical compounds. The performance of PGA bioflocculant was superior to that of the other coagulants. In the dry season, 80 mg L-1 of PG alpha 21Ca removed 89.74% of apparent color, and residual turbidity was 5.78 NTU. In the rainy season, 90 mg L-1 of PG alpha 21Ca removed 96.89% of apparent color and residual turbidity was 1.93 NTU. (C) 2016 Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 15/02650-8 - Produção e aplicação ambiental de ácido y-poliglutâmico através do cultivo de B. subtilis em substrato de soja
• Beneficiário: Valquiria de Campos
• Modalidade de apoio: Auxílio à Pesquisa - Regular