Substrate removal kinetics and performance assessment of a vermifilter bioreactor under organic shock load conditions

2016 ◽  
Vol 74 (5) ◽  
pp. 1177-1184 ◽  
Author(s):  
Tarun Kumar ◽  
K. S. Hari Prasad ◽  
Nitin Kumar Singh
Keyword(s):  
Oxygen Demand ◽  
Domestic Wastewater ◽  
Pilot Scale ◽  
Shock Load ◽  
Order Kinetic ◽  
Shock Loads ◽  
Normal Loading ◽  
Substrate Removal ◽  
Order Kinetic Model ◽  
And Performance

In the present study, the effect of short-term organic shock loads (675, 799, 1,084 and 1,410 mg COD/L) on the treatment performance of a pilot-scale vermifilter (VF), employing an epigeic earthworm Eisenia fetida and treating synthetic domestic wastewater is investigated. The effect of organic shock loads on the performance and stability of vermifiltration reactor was evaluated to identify its feasibility in actual field conditions. Prior to the application of each organic shock load, normal loading conditions were maintained to achieve the pseudo steady state (PSS) conditions. The results showed satisfactory endurance against imposed organic shock loads with negligible reduction in chemical oxygen demand (COD) removals and it was almost similar to PSS condition with removal efficiencies of ∼ 66, 71, 67 and 68%, respectively. The experimental COD data fit well to first-order kinetic model, with a regression value of 0.95. At the end of all shock loads, the nutritional analysis of vermicompost obtained from the top layer of VF, showed increased concentration of total nitrogen (∼31 g/Kg) and total phosphorus (29 g/Kg). Besides, an augmented earthworm biomass, ∼23.2% on weight basis and ∼22% on number basis, was observed at the end of the study.

Influence of agitation rate on the performance of a stirred anaerobic sequencing batch reactor containing immobilized biomass

2001 ◽  
Vol 44 (4) ◽  
pp. 305-312 ◽  
Author(s):  
S. M. Ratusznei ◽  
J. A.D. Rodrigues ◽  
E. F.M. Camargo ◽  
M. Zaiat ◽  
W. Borzani
Keyword(s):  
Sequencing Batch Reactor ◽  
Batch Reactor ◽  
Domestic Wastewater ◽  
Agitation Rate ◽  
Order Kinetic ◽  
Mechanical Agitation ◽  
Anaerobic Sequencing Batch Reactor ◽  
Substrate Removal ◽  
Order Kinetic Model ◽  
Immobilized Biomass

The present work reports on the influence of the mechanical agitation rates on the performance of a stirred anaerobic sequencing batch reactor containing immobilized biomass on polyurethane foam, as inert support, treating synthetic domestic wastewater. The reactor was operated at 30°C and an 8-hour cycle was used to treat approximately 0.5 L of the synthetic substrate with a COD concentration of nearly 500 mg/L. The studied agitation rates ranged from no agitation to 750 rpm. The system attained non-filtered substrate removal efficiency greater than 83% when agitation was employed. A very short start-up period and good solid retention could be observed. The use of agitation increased the efficiency of the reactor and enabled reduction of the total cycle time. An empirical equation and a first-order kinetic model are proposed to analyze the influence of agitation rates on the reactor's performance.

Sustainable wastewater management technology for tourism in Thailand: case and experimental studies

2019 ◽  
Vol 79 (10) ◽  
pp. 1977-1984
Author(s):  
W. Liamlaem ◽  
L. Benjawan ◽  
C. Polprasert
Keyword(s):  
Kinetic Constant ◽  
Experimental Studies ◽  
Oxygen Demand ◽  
Domestic Wastewater ◽  
Wastewater Management ◽  
Order Kinetic ◽  
First Order ◽  
Treated Effluent ◽  
Management Technology ◽  
Pre Treatment

Abstract Thailand has adopted the concept of eco-tourism as a protocol to protect environmental resources. One of the key factors in enabling the achievement of this goal is the improvement of the quality of effluent from those homestays and resorts which still lack efficient on-site wastewater treatment. This research utilized case studies of subsurface flow constructed wetlands (SFCWs), planted mainly with the Indian shot (Canna indica L.), which were designed to treat wastewaters at three resorts located in Amphawa District, Samut Songkram Province in central Thailand. The results showed that the treated effluent was of sufficient quality to meet the building effluent standards Type C, which require the concentrations of biological oxygen demand (BOD), total Kjeldahl nitrogen (TKN) and suspended solids (SS) to be less than 40, 40 and 50 mg/L, respectively. In addition, the first-order kinetic constants for the design and operation of SFCWs were determined. For treating wastewater containing organic substances, with no prior pre-treatment, the first-order kinetic constant of 0.24 1/d can be applied to predict effluent quality. For treating other types of domestic wastewater, a first-order kinetic constant in the range 0.40–0.45 1/d can be used when sizing and operating SFCWs. This research highlights the great potential of SFCWs as a sustainable wastewater management technology.

scholarly journals Optimising the Hydraulic Retention Time in a Pilot-Scale Microbial Electrolysis Cell to Achieve High Volumetric Treatment Rates Using Concentrated Domestic Wastewater

Molecules ◽  
2020 ◽  
Vol 25 (12) ◽  
pp. 2945 ◽  
Author(s):  
Daniel D. Leicester ◽  
Jaime M. Amezaga ◽  
Andrew Moore ◽  
Elizabeth S. Heidrich
Keyword(s):  
Retention Time ◽  
Hydraulic Retention Time ◽  
Oxygen Demand ◽  
Domestic Wastewater ◽  
Direct Analysis ◽  
Pilot Scale ◽  
Electrolysis Cell ◽  
Treatment Technique ◽  
Microbial Electrolysis Cell ◽  
Microbial Electrolysis

Bioelectrochemical systems (BES) have the potential to deliver energy-neutral wastewater treatment. Pilot-scale tests have proven that they can operate at low temperatures with real wastewaters. However, volumetric treatment rates (VTRs) have been low, reducing the ability for this technology to compete with activated sludge (AS). This paper describes a pilot-scale microbial electrolysis cell (MEC) operated in continuous flow for 6 months. The reactor was fed return sludge liquor, the concentrated filtrate of anaerobic digestion sludge that has a high chemical oxygen demand (COD). The use of a wastewater with increased soluble organics, along with optimisation of the hydraulic retention time (HRT), resulted in the highest VTR achieved by a pilot-scale MEC treating real wastewater. Peak HRT was 0.5-days, resulting in an average VTR of 3.82 kgCOD/m3∙day and a 55% COD removal efficiency. Finally, using the data obtained, a direct analysis of the potential savings from the reduced loading on AS was then made. Theoretical calculation of the required tank size, with the estimated costs and savings, indicates that the use of an MEC as a return sludge liquor pre-treatment technique could result in an industrially viable system.

Membrane fouling and performance evaluation of conventional membrane bioreactor (MBR), moving biofilm MBR and oxic/anoxic MBR

2014 ◽  
Vol 69 (7) ◽  
pp. 1403-1409 ◽  
Author(s):  
Sher Jamal Khan ◽  
Aman Ahmad ◽  
Muhammad Saqib Nawaz ◽  
Nicholas P. Hankins
Keyword(s):  
Membrane Fouling ◽  
Extracellular Polymeric Substances ◽  
Water Flux ◽  
Oxygen Demand ◽  
Domestic Wastewater ◽  
Membrane Bioreactors ◽  
Nitrogen And Phosphorus ◽  
Biofilm Carrier ◽  
Cake Layer ◽  
And Performance

In this study, three laboratory scale submerged membrane bioreactors (MBRs) comprising a conventional MBR (C-MBR), moving bed MBR (MB-MBR) and anoxic-oxic MBR (A/O-MBR) were continuously operated with synthesized domestic wastewater (chemical oxygen demand, COD = 500 mg/L) for 150 days under similar operational and environmental conditions. Kaldnes® plastic media with 20% dry volume was used as a biofilm carrier in the MB-MBR and A/O-MBR. The treatment performance and fouling propensity of the MBRs were evaluated. The effect of cake layer formation in all three MBRs was almost the same. However, pore blocking caused a major difference in the resultant water flux. The A/O-MBR showed the highest total nitrogen and phosphorus (PO4-P) removal efficiencies of 83.2 and 69.7%, respectively. Due to the high removal of nitrogen, fewer protein contents were found in the soluble and bound extracellular polymeric substances (EPS) of the A/O-MBR. Fouling trends of the MBRs showed 12, 14 and 20 days filtration cycles for C-MBR, MB-MBR and A/O-MBR, respectively. A 25% reduction of the soluble EPS and a 37% reduction of the bound EPS concentrations in A/O-MBR compared with C-MBR was a major contributing factor for fouling retardation and the enhanced filtration capacity of the A/O-MBR.

Pilot-scale study of an anaerobic baffled reactor for the treatment of domestic wastewater

2002 ◽  
Vol 46 (9) ◽  
pp. 263-270 ◽  
Author(s):  
P. Dama ◽  
J. Bell ◽  
K.M. Foxon ◽  
C.J. Brouckaert ◽  
T. Huang ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Service Providers ◽  
Treatment Options ◽  
Oxygen Demand ◽  
Domestic Wastewater ◽  
Pilot Scale ◽  
Anaerobic Baffled Reactor ◽  
South Africans ◽  
Laboratory Reactor ◽  
Poor Infrastructure

Large proportions of South Africans live in areas with inadequate sanitation and a poor infrastructure for waterborne sanitation. Service providers are looking for alternative wastewater treatment options. The anaerobic baffled reactor is being considered as a decentralised sanitation option in these areas. A 3,200 L reactor was built and is currently being evaluated at a wastewater treatment works. The reactor was built based on experiences gained from working with a laboratory reactor (10 L) and predicted flow patterns observed on a computational fluid dynamics model. The design and construction of the reactor will be discussed in this paper. The feed to the reactor consists of screen degritted sewage and the flow to the reactor is maintained by means of a programmable logic controller. The pilot-plant layout is discussed in this paper. Samples are analysed for chemical oxygen demand, pH, alkalinity, ammonia, phosphorus, solids and ash content. Reductions of between 70 and 80% are obtained for COD and the pH values for the effluent samples are within the discharge limits.

scholarly journals Removal of COD from Groundwater in and Around Industrial Areas - Using Activated Carbon Powder Prepared by Groundnut Foliage and Groundnut Husk

2021 ◽  
Vol 37 (4) ◽  
pp. 922-927
Author(s):  
A. Kistan ◽  
V. Kanchana ◽  
N. K. Geetha ◽  
G. Infant Sujitha
Keyword(s):  
Activated Carbon ◽  
Kinetic Model ◽  
Adsorption Process ◽  
Oxygen Demand ◽  
Carbon Powder ◽  
Order Kinetic ◽  
Industrial Areas ◽  
Sem Image ◽  
Order Kinetic Model ◽  
Pseudo Second Order

The following study explains that the adsorption efficiency of activated carbon used by Groundnut foliage and groundnut husk for the deportation of COD (Chemical Oxygen demand) from groundwater collected from in and around industrial areas of Vellore district was investigated with different activating conditions (Activating agent- KOH, ZnCl2 and H3PO4; Impregnation ratio-1:1,1:2,1:2; and activation temeperture-500-700°C. The activated carbon prepared based on optimized condition has well-developed pore structure and functional groups which is confirmed from SEM image and FTIR analysis respectively. The adsorption equilibrium was reached in 240 min with the isotherm data fitted well in both the model such as Langmuir model and Freundlich’s model indicating chemisorption’s adsorption for the activated carbon. Moreover, the adsorption process was exothermic accompanied by a decrease in irregularity. Furthermore, the adsorption kinetic study indicated that the adsorption process of the prepared sample follows the pseudo-second-order kinetic model compare to the pseudo-first -order kinetic model

Utilization of Oxygen Models in Environmental Impact Analysis

1977 ◽  
Vol 12 (1) ◽  
pp. 135-156 ◽  
Author(s):  
W.J. Snodgrass ◽  
M.F. Holloran
Keyword(s):  
Impact Analysis ◽  
Management Strategies ◽  
Oxygen Demand ◽  
Sediment Oxygen Demand ◽  
Order Kinetic ◽  
Temperature Model ◽  
One Dimensional ◽  
Order Kinetic Model ◽  
Anoxic Zones

Abstract A vertical one-dimensional temperature-oxygen model for reservoirs is used to estimate zones of stress on the aquatic environment of a series of reservoirs in Nova Scotia. Application to cold climates necessitated a few novel developments for the temperature model. The oxygen model whose sinks are water column decay and sediment oxygen demand (SOD) is calibrated using under ice measurements of oxygen stocks and laboratory and in situ measurements of a zero-order kinetic model for sediment oxygen demand. These extensive studies are complementary and indicate a winter SOD of 0.1 gm 02/m2/day and a higher summer value. High epilimnetic temperatures coupled with the predicted anoxic zones in lower waters cause a major stress upon fisheries potential. This model provides a tool for determining the effects of different reservoir management strategies upon water quality and for selecting among these strategies.

Comparative study of membrane bioreactor (MBR) and activated sludge processes in the treatment of Moroccan domestic wastewater

2018 ◽  
Vol 78 (5) ◽  
pp. 1129-1136 ◽  
Author(s):  
S. Kitanou ◽  
M. Tahri ◽  
B. Bachiri ◽  
M. Mahi ◽  
M. Hafsi ◽  
...  
Keyword(s):  
Activated Sludge ◽  
Membrane Bioreactor ◽  
Ceramic Membrane ◽  
Oxygen Demand ◽  
Domestic Wastewater ◽  
Pilot Scale ◽  
Quality Parameters ◽  
Effluent Quality ◽  
Conventional Activated Sludge ◽  
Activated Sludge Processes

Abstract The study was based on an external pilot-scale membrane bioreactor (MBR) with a ceramic membrane compared to a conventional activated sludge process (ASP) plant. Both systems received their influent from domestic wastewater. The MBR produced an effluent of much better quality than the ASP in terms of total suspended solids (TSS), 5-day biological oxygen demand (BOD5) and chemical oxygen demand (COD), total phosphorus (TP) and total nitrogen (TN). Other effluent quality parameters also indicated substantial differences between the ASP and the MBR. This study leads to the conclusion that in the case of domestic wastewater, MBR treatment leads to excellent effluent quality. Hence, the replacement of ASP by MBR may be justified on the basis of the improved removal of solids, nutrients, and micropollutants. Furthermore, in terms of reuse the high quality of the treated water allows it to be reused for irrigation.

scholarly journals Performance of Novel Contact Stabilization Activated Sludge System on Domestic Wastewater Treatment

2015 ◽  
Vol 19 (2) ◽  
pp. 7
Author(s):  
Andrés Felipe Torres Franco ◽  
Nancy Vásquez Sarria ◽  
Jenny Rodriguez Victoria
Keyword(s):  
Activated Sludge ◽  
Oxygen Demand ◽  
Domestic Wastewater ◽  
Growth Zone ◽  
Pilot Scale ◽  
Ammonia Nitrogen ◽  
Activated Sludge System ◽  
Suspended Growth ◽  
Removal Efficiencies ◽  
Final Effluent

A pilot-scale study was conducted to evaluate a traditional contact stabilization activated sludge system (CSASC) and a modified CSAS (CSASM) treating domestic wastewater. The CSASC system was comprised of a contact reactor (CR), a stabilization reactor (SR) and a secondary settler (SS); the CSASM included a second CR, a second SS (CR2 and SS2), and a modified SR (SRM) divided into four zones: an attached-suspended growth zone which allowed the system to reach an average sludge retention time close to 36 d and favored the occurrence of nitrification; an anoxic zone for denitrification occurrence; an aerated suspended growth zone with a high presence of organic carbon; and an additional aerated suspended growth zone with a high ammonia concentrations environment. The CSASC’s removal efficiencies of chemical oxygen demand (COD) and total ammonia nitrogen (TAN) were respectively 94±4 % and 53±12%; whereas CSASM’s efficiencies were 88±7% for COD and 92±7% for TAN. Concentrations of TAN and NO3 --N in the CSASC’s final effluent were 14.3±5.2 and 5.0±2.9 mg×L-1; and 4.8±4.4 and 9.1±5.8 mg×L-1 in the CSASM’s final effluent. Results demonstrated that the proposed configuration obtained higher nitrogen removal efficiencies than traditional CSAS.</p>

Treatment of low and medium strength sewage in a lab-scale gradual concentric chambers (GCC) reactor

2008 ◽  
Vol 57 (8) ◽  
pp. 1155-1160 ◽  
Author(s):  
L. Mendoza ◽  
M. Carballa ◽  
L. Zhang ◽  
W. Verstraete
Keyword(s):  
Removal Efficiency ◽  
Loading Rate ◽  
Oxygen Demand ◽  
Domestic Wastewater ◽  
Organic Loading Rate ◽  
Medium Strength ◽  
Low Strength ◽  
And Performance ◽  
Scale Design ◽  
Final Effluent

One of the major challenges of anaerobic technology is its applicability for low strength wastewaters, such as sewage. The lab-scale design and performance of a novel Gradual Concentric Chambers (GCC) reactor treating low (165±24 mg COD/L) and medium strength (550 mg COD/L) domestic wastewaters were studied. Experimental data were collected to evaluate the influence of chemical oxygen demand (COD) concentrations in the influent and the hydraulic retention time (HRT) on the performance of the GCC reactor. Two reactors (R1 and R2), integrating anaerobic and aerobic processes, were studied at ambient (26°C) and mesophilic (35°C) temperature, respectively. The highest COD removal efficiency (94%) was obtained when treating medium strength wastewater at an organic loading rate (OLR) of 1.9 g COD/L·d (HRT = 4 h). The COD levels in the final effluent were around 36 mg/L. For the low strength domestic wastewater, a highest removal efficiency of 85% was observed, producing a final effluent with 22 mg COD/L. Changes in the nutrient concentration levels were followed for both reactors.

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