Wastewater Treatment of Wet Coffee Processing in an Anaerobic Baffled Bioreactor Coupled to Microfiltration System

Abstract

Background: Wet coffee processing consists of the removal of the pulp and mucilage of the coffee cherry. This process generates a large amount of acidic wastewater which is very aggressive to the environment because of its high content of recalcitrant organic matter. Therefore, treatment is necessary before discharge to water bodies. Because of this reason, this study aimed to evaluate the organic matter removal efficiency in an Anaerobic Baffled Bioreactor (ABR) coupled to a Microfiltration Membrane (MF) system as a new eco-friendly option in the treatment of wet Coffee Processing Wastewater (CPWW). Methods: Two systems (S1 and S2) were evaluated at Hydraulic Retention Times (HRT) of 59 h and 83 h, respectively. Both systems were operated at mesophilic conditions, at a Transmembrane Pressure (TMP) of 50 kPa during 1800 h. Results: The S2 generated higher organic matter removal efficiency, reaching removal values of turbidity of 98.7%, Chemical Oxygen Demand (COD) of 81%, Total Solids (TS) of 72.6%, Total Suspended Solids (TSS) of 100%, and Total Dissolved Solids (TDS) of 61%, compared with the S1. Conclusion: The S2 represents a new eco-friendly alternative to treat CPWW and reduce its pollutant effect.

Evaluation of a New Method for Treating Coffee Effluent

“…5). The reported TSS content in fresh coffee effluent varies widely and it ranged from 399 mg/l (Nor Sakinah Mohdsaid et al, 2019), 1,450 mg/l (Workineh et al, 2020), 2,390 mg/l (Veymar et al, 2019) and 2,820 mg/l (Selvamurugan et al, 2010). The data on the influence of effluent treatment methods on TSS content indicated that the average TSS reduction by CCRI-NEERI treatment method was 61% (Fig.…”

“…The CCRI-NEERI ETP unit is basically an anaerobic-cum-aerobic digestion method and it takes about a month time for treating the coffee effluent (Shanmukhappa et al, 1998). Several reports have been published for the treatment of coffee effluent following physio-chemical (Aguilera et al, 1998;Bhaskar et al, 2008;Tokumura et al, 2008;Asha et al, 2015;Panchangam et al, 2015;Hermosilla, 2016;Tomizawa et al, 2016;Sahana et al, 2018 andVeymar et al, 2019), chemicals (Teresa et al, 2007;Zayas Péerez et al, 2007;Novita et al, 2012 andWorkineh et al, 2020), biological (Selvamurugan et al, 2010, Yans Guardia Puebla et al, 2013, Chagas et al, 2015Padmapriya et al, 2015;Hubbe et al, 2016;Torres et al,. 2016;Cruz-Salomón et.…”

“…2016;Cruz-Salomón et. al., 2018;Navitha et al, 2018;Tacias-Pascacio et al, 2019 andWorkineh et al, 2020) and phytoremediation (Nor Sakinah Mohdsaid et al, 2019) methods.…”

Potential of Using Dual-Media Biofilm Reactors as a Real Coffee Industrial Effluent Pre-Treatment

“…Thus, the current focus is to discover the most effective wastewater treatment method using low-cost sustainable technology to save the environment from the threat posed by coffee effluent [9]. In previous studies, various approaches were utilised to remove pollutants from coffee effluents, including zero-valent iron (ZVI) treatment [10], the photo-Fenton method [11], ultraviolet (UV) radiation catalysis (with ozone) [12], electro-oxidation [13], membrane filtration [14,15], chemical coagulation and flocculation [16]. However, due to the high footprint requirement, high energy consumption and huge operation and maintenance costs [17], most of their use is restrained and requires steady financial input.…”