Anaerobic Baffled Reactor

This study assesses a modified anaerobic granular bed baffled reactor (GRABBR) which was assessed for wastewater treatment at high organic loading rates (chemical oxygen demand > 1100 mg/l) under varying temperatures. For the two mesophilic temperatures tested (37 ˚C and 25 ˚C) under steady state conditions, the removal of Chemical Oxygen Demand (COD) and Biochemical Oxygen Demand (BOD) was 80 to 90 %. At lower organic loadings, the reactor operated as a completely mixed system with most of the treatment occurring in the first two compartments. The GRABBR also showed very high solids retention with low effluent suspended solids concentration for all organic and hydraulic conditions. Applications of GRABBR as a single unit, two-phase treatment system could be an economical option reducing the cost to achieve similar treatment goals of high strength wastewaters. The findings of this research suggest that the application of GRABBR is suitable for treatment of multiple pollutants pre...

Como resultado de la Consultoría realizada por CCA Biogás quedó conformada la versión final del STAR de PROTENA cuyo esquema simplificado de operación se muestra más abajo (Figura 1). Como se puede apreciar, en esta nueva versión del STAR predominan los componentes anaerobios ya que solamente su último componente es principalmente aerobio, aunque como es aerobio/facultativo, también tiene una sección anaerobia en su parte inferior. Esta configuración predominantemente anaerobia es muy ventajosa desde el punto de vista energético, ya que sólo se requieren dos equipos mecánicos en todo el sistema: la bomba que lleva los RILes desde el RAB hasta la LAN y la que distribuye el efluente de la LAEF para que se use en el riego. Por el contrario, casi todos los equipos producen energía, en forma de biogás e incluso el RAB lo produce en una cantidad significativa, con alto potencial de sustitución de Gas Licuado del Petróleo (GLP).
Finalmente, el 29 de septiembre de 2020 comenzó la etapa de construcción del RAB, la que terminó el 23 de noviembre, día en que se hizo entrega oficial del Proyecto al equipo de la UGA de PROTENA. En el presente informe se hace un resumen del trabajo realizado por CCA Biogás y se especifican las condiciones que debe crear PROTENA para que pueda realizarse adecuadamente la Puesta en Marcha y la planta logre alcanzar la eficiencia prevista, en dependencia de la capacidad de Procesamiento de Sangre.

The treatment and reuse of domestic wastewater using an anaerobic baffled reactor (ABR) followed by a duckweed pond (DWP) were the main theme of the present study. The ABR was fed continuously with domestic wastewater at four HRTs ranging from 8 to 24 h and corresponds to organic loading rates ranging from 0.67 to 2.1 kg COD/m3/day. The ABR effluent was fed to a DWP operating at 10 and 15 days. The performance of the ABR at the four HRTs gave satisfactory results. Chemical oxygen demand (COD) removal was between 68 and 82%. Fecal coliform removal was between 1 to 2 logs. The 12- and 18-h hydraulic retention times (HRTs) gave close results, as indication of the possible selection of the 12-h HRT as the optimum operation for the ABR based on economic advantage. The ABR compartmentalized structure gave results higher than those produced by the one-stage digester and similar to those produced by the two-phase anaerobic digestion process. Duckweed ponds as post-treatment operated at 10 days and 15 days gave the best results at 15-day HRT, where it was possible to remove 73.4% of nitrogen and 65% of phosphorus and produce protein-rich dry duckweed of 105 kg/ha/day on average. The removal of fecal coliform (FC) in duckweed ponds was 3–4 logs. The final treated domestic sewage characteristics proved its compliance with the Egyptian standards for reuse in restricted irrigation.

Retting is a process of immersion of coconut husks in water for manufacture of good quality coir fiber. Open retting of coconut husks in water bodies is the conventional method which causes serious environmental problems due to emission of green house gases. The pollution due to open retting practice accounts to biodegradable COD and large quantities of non-biodegradable poly phenols in the retting water bodies. This has been affecting natural heritage of rich biodiversity in the backwater bodies. Mechanical and chemical methods for extraction of fiber are found not to be feasible solutions because of low quality and economics. Closed retting, an alternative to open retting is a process in which soaking liquor is treated in a high rate anaerobic reactor. In this retting method biodegradable organics are converted to VFA fractions like acetic, propionic and butyric acids and finally to CH 4. There is no sulphide generation in this process as fresh water can be used for producing quality fibers. The present study analyses the performance of an anaerobic baffled reactor (ABR) in the treatment of husk soaking liquor. A laboratory scale Anaerobic Baffled Reactor and retting tank was fabricated and the efficiency of the system was evaluated by analyzing the parameters like, Alkalinity, pH, COD and total Suspended Solids etc. The analysis indicated favourable atmosphere for anaerobic reaction within the reactor and he working performance of anaerobic baffled reactor in the treatment of husk liquor is found to be satisfactory.

An anaerobic baffled reactor (ABR) (3 000 L) was investigated for on-site sanitation for low-income communities. The eight-compartment reactor allows high solids retention with high treatment rates, and is stable to organic and hydraulic shock loads. The reactor was fed with raw domestic wastewater from a middle-income community at a wastewater treatment facility. A previous study on the pilot-scale ABR, operated at an average HRT of 22 h, revealed that there was no phase separation in the reactor, due to the slow rate of hydrolysis. Hydrolytic and acidogenic bacteria were located in all compartments of the reactor, with a few scavenging methanogens in the first few compartments. The objective of this study was to therefore investigate the hypothesis that a better spatial separation might occur at a longer HRT. When the HRT was increased to 40-44 h, a partial separation of acidogenic and methanogenic phases was observed, using scanning electron microscopy (SEM). Scavenging by micro-...

The treatment and reuse of domestic wastewater using an anaerobic baffled reactor (ABR) followed by a duckweed pond (DWP) were the main theme of the present study. The ABR was fed continuously with domestic wastewater at four HRTs ranging from 8 to 24 h and corresponds to organic loading rates ranging from 0.67 to 2.1 kg COD/m3/day. The ABR effluent was fed to a DWP operating at 10 and 15 days. The performance of the ABR at the four HRTs gave satisfactory results. Chemical oxygen demand (COD) removal was between 68 and 82%. Fecal coliform removal was between 1 to 2 logs. The 12- and 18-h hydraulic retention times (HRTs) gave close results, as indication of the possible selection of the 12-h HRT as the optimum operation for the ABR based on economic advantage. The ABR compartmentalized structure gave results higher than those produced by the one-stage digester and similar to those produced by the two-phase anaerobic digestion process. Duckweed ponds as post-treatment operated at 10 d...

Como resultado de la Consultoría realizada por CCA Biogás quedó conformada la versión final del STAR de PROTENA cuyo esquema simplificado de operación se muestra más abajo (Figura 1). Como se puede apreciar, en esta nueva versión del STAR predominan los componentes anaerobios ya que solamente su último componente es principalmente aerobio, aunque como es aerobio/facultativo, también tiene una sección anaerobia en su parte inferior. Esta configuración predominantemente anaerobia es muy ventajosa desde el punto de vista energético, ya que sólo se requieren dos equipos mecánicos en todo el sistema: la bomba que lleva los RILes desde el RAB hasta la LAN y la que distribuye el efluente de la LAEF para que se use en el riego. Por el contrario, casi todos los equipos producen energía, en forma de biogás e incluso el RAB lo produce en una cantidad significativa, con alto potencial de sustitución de Gas Licuado del Petróleo (GLP). Finalmente, el 29 de septiembre de 2020 comenzó la etapa de construcción del RAB, la que terminó el 23 de noviembre, día en que se hizo entrega oficial del Proyecto al equipo de la UGA de PROTENA. En el presente informe se hace un resumen del trabajo realizado por CCA Biogás y se especifican las condiciones que debe crear PROTENA para que pueda realizarse adecuadamente la Puesta en Marcha y la planta logre alcanzar la eficiencia prevista, en dependencia de la capacidad de Procesamiento de Sangre.

The treatment and reuse of domestic wastewater using an anaerobic baffled reactor (ABR) followed by a duckweed pond (DWP) were the main theme of the present study. The ABR was fed continuously with domestic wastewater at four HRTs ranging from 8 to 24 h and corresponds to organic loading rates ranging from 0.67 to 2.1 kg COD/m3/day. The ABR effluent was fed to a DWP operating at 10 and 15 days. The performance of the ABR at the four HRTs gave satisfactory results. Chemical oxygen demand (COD) removal was between 68 and 82%. Fecal coliform removal was between 1 to 2 logs. The 12- and 18-h hydraulic retention times (HRTs) gave close results, as indication of the possible selection of the 12-h HRT as the optimum operation for the ABR based on economic advantage. The ABR compartmentalized structure gave results higher than those produced by the one-stage digester and similar to those produced by the two-phase anaerobic digestion process. Duckweed ponds as post-treatment operated at 10 d...

The performance of biochar media filters derived from cocoa pod husk (CC) and coconut shell (CN) was assessed in comparison with sand media (SS), under a range of hydraulic loading rates (HLR) (0.105-0.210 m 3 /m 2 .d) during a 9 weeks study period. The results at the end of week 7 under a HLR of 0.105m ³/m ².d, showed CC had the best removal efficiency with respect to the nutrients (TKN (95.56%), NH 3-N (99.68%), Total-P (89.33%) and pathogens (E. coli non-detected), meeting the Ghana Environmental Protection Agency (GH EPA) guideline values with the exception of Total-P (2.15 mg/L). CN failed to meet the GH EPA limits for Total-P (6.6mg/L), NH 3-N (8.6mg/L) and E.coli (30 cfu/100ml). SS failed to meet any of the GH EPA guideline with respect to nutrient and pathogen. The performance of SS, CC and CN were all observed to deteriorate in week 8 when the HLR was increased to 0.120 m 3 /m 2 /d (doubled). However, the GH EPA limit with respect to Total-P was met by CC (1.93mg/L). With a...

This WRC funded project has studied the appropriateness of the ABR (anaerobic baffled reactor) for on-site primary sanitation in low-income communities. A 3,000 L pilot reactor was located at the Kingsburgh wastewater treatment plant south of Durban, South Africa. Feed to the reactor was raw domestic wastewater containing a significant proportion of particulate organic matter. The compartments of the ABR were routinely monitored for pH, COD, and gas production, among other physical-chemical determinants. The microbial population in each compartment was analysed by fluorescent in situ hybridisation, using general oligonucleotide probes for eubacteria and archeae and a suite of 10 genera or family specific probes. Scanning electron microscopy was conducted on the sludge fraction of each compartment. Mixed fractions from each compartment were also analysed for health-related indicator bacteria (total coliforms and E. coli). Results indicated that methanogenesis was not occurring to the...