Integrating coagulation-flocculation and UV-C or H2O2/UV-C as alternatives for pre- or complete treatment of biodiesel effluents

Impact of biodiesel production on wastewater generation

“…The advanced processes are of great interest in the treatment of effluents with high organic load or with toxic characteristics (COSTA et al, 2017), issues often associated with wastewater resulting from biodiesel washing (BRITO et al, 2019). These processes are often applied in combination, together with a pretreatment step involving flocculation/coagulation.…”

“…The combination of treatments is relevant for complex effluents, such as biodiesel, and allows combining the efficiency of physical/chemical/ biological processes, which is interesting, especially in the case of recalcitrant compounds, which are hardly removed by conventional methods (BHANOT et al, 2020). In this context, combined treatments have aroused the interest of researchers to evaluate the combination of two or more treatments; as an example of combined treatments, we have radiation UVC and H 2 O 2 (COSTA et al, 2017), oxidation and coagulation (YANG et al, 2017), membrane filtration and Fenton , flocculation/ coagulation and electrochemical (TORRES et al, 2018), and HMBB/Fenton (GONÇALVES et al, 2019), and among these, FM-Fenton resulted in greater removal of COD and O&G. et al (2019) reported that BW had low biodegradability (BOD/COD ratio = 8.6 × 10 −3 ), making the application of wet air oxidation (WAO) treatment conducive, in which the insoluble organic matter is transformed into simpler soluble compounds. WAO occurs through a radical oxidation mechanism involving organic radicals and peroxides; however, a recalcitrant effect was noted, probably due to the high temperature resistance of the oxidation intermediates generated after treatment.…”

“…The effluent generated from this process has a high organic load, which increases the values for chemical oxygen demand (COD) and biological oxygen demand (BOD). In addition, there is the presence of oil and grease (O&G) and variations in the pH values, depending on the method used in the production step (COSTA et al, 2017;BASHIR et al, 2018). These aspects mean that treatment is necessary to allow proper disposal.…”

Tratamento de efluente de biodiesel pela integração dos processos de coagulação-floculação, UV-C e oxidação avançada

“…Este procedimento foi feito para evitar reações paralelas ineficientes do H 2 O 2 , o que diminui a eficiência do processo de degradação conforme mencionado anteriormente , Costa et al, 2017 (Vogel et al, 2000).…”

Potencial do processo foto-Fenton como etapa complementar ao tratamento de esgoto urbano e efluentes de indústria agroquímica

“…Em seguida, o sobrenadante seguiu para segunda etapa de tratamento via fotodegradação (processo foto-4.9.1 Processos de coagulação-floculação-decantação: primeira etapa sequestradores e, aumentam o tempo de tratamento e o consumo de H2O2(SILVA et al, 2016). Além disso, em estudos anteriores avaliando coagulantes com as possíveis combinações entre Al 3+ ou Fe 3+ e esses três diferentes ânions (Cl -, NO3e SO4 2-) foi observado que as maiores remoções de cor, turbidez e sólidos em suspensão foram alcançadas usando Al 3+ ou Fe 3+ a partir dos respectivos sais Al(NO3)3 e Fe(NO3)3(COSTA et al, 2017;SILVA et al, 2017).…”