Performance of an anaerobic baffled reactor with an aerobic chamber treating low-strength wastewater

Abstract

a b s t r a c tThe objective of this study was to evaluate the performance of an anaerobic baffled reactor (ABR) with an aerobic chamber (AC) in the treatment of domestic wastewater with a low organic load (0.10 ± 0.02 to 0.51 ± 0.10 kg COD·m -3 ·d -1). The entire system consisted of three anaerobic chambers (C1, C2, C3), one aerobic chamber (AC) and one laminar settling tank (LST), operated for 30 weeks , with average concentrations of 214 ± 63 mg·L -1 in the influent and 48 ± 25 mg·L -1 in the effluent. Considering the entire system (ABR + AC + LST), the values of total removal efficiency for COD varied between 49 and 92%, with an average removal of 78 ± 9%. No accumulation of volatile fatty acids (VFA) was found, as the VFA concentration remained between 32 and 76 mg HAc·L -1 at the influent and between 21 and 53 mg HAc·L -1 at C3. Bio molecular analyses showed a great variety of bacterial communities established in all phases of monitoring and low archaeal community diversity. The combined configuration (ABR + AC) has shown great potential for the treatment of domestic wastewater, thereby being considered as a promising alternative for decentralized treatment.

Disinfection of anaerobic/aerobic sanitary effluent using ozone: Formaldehyde formation

“…The AABR was operated during the study period with a flow rate of 24 L/hr, organic loading rate of 0.10 ± 0.02 kg COD m −3 day −1 , and TDH of 33 hr, and according to studies by Da Silva et al. (), an efficiency of 77 ± 10% COD removal was obtained in the period.…”

“…The effluent that was used in this study was collected in the outlet of the laminar decanter. Da Silva, Sarti, Maintinguer, Kaiser, and Da Silva (2017) were the researchers responsible for describing and studying the efficiency of this system.…”

“…A schematic diagram of the Water Resource Recovery Facility is shown in Figure 1, including the disinfection step with ozone. The AABR was operated during the study period with a flow rate of 24 L/hr, organic loading rate of 0.10 ± 0.02 kg COD m −3 day −1 , and TDH of 33 hr, and according to studies by Da Silva et al (2017), an efficiency of 77 ± 10% COD removal was obtained in the period.…”

“…Schematic diagram of the Water Resource Recovery facility: 1, raw wastewater; 2, screen; 3, settling tank; 4, equalization tank; 5, pump; 6, storage tank; 7, AABR inlet; 8, chamber sampling points (for the present study, the higher points were used); 9, chamber 1; 10, chamber 2; 11, chamber 3; 12, air diffusers; 13, anaerobic chamber; 14, bamboo rings; 15, air flow meter; 16, air compressor; 17, plastic plates; 18, AABR outlet; 19, sludge exit; 20, laminar settling tank; 21, oxygen generator; 22, rotameter (O2 flow); 23, ozone generator; 24, regulator of % of ozone production; 25, ozone in; 26, effluent; 27, batch bubble column; 28, porous diffuser; 29, influent; 30, off-gas; 31, ozone destruct. Adapted by Da Silva et al (2017) and Miranda et al (2014).…”

Anaerobic Treatment of Domestic Wastewater

“…The choice of a post-treatment strongly depends on the characteristics of the anaerobic effluent and on local law standards for the reuse of the treated effluent or discharge to the environment Anaerobic treatment of low-strength wastewater: applicability and hygienization potential (Kujawa-Roeleveld & Zeeman, 2006). Several post-treatment methods have been proposed in the literature: some examples are waste stabilization ponds (Van Haandel & Lettinga, 1994), trickling filters (Chernicharo & Nascimento, 2001), dynamic membrane filters (Quek et al, 2017), aerobic chambers (Da Silva et al, 2017), activated sludge (Von Sperling et al, 2001), and constructed wetlands (El-Khateeb et al, 2009). Among them, aerobic post-treatment was demonstrated to be effective in enhancing sludge stabilization (Tomei & Carozza, 2015) and pathogen removal (Tomei et al, 2016); whereas constructed wetlands are particularly suitable for decentralized wastewater treatment in rural areas (Álvarez et al, 2008).…”