Comparison of two treatments for the removal of selected organic micropollutants and bulk organic matter: conventional activated sludge followed by ultrafiltration versus membrane bioreactor

The potential of membrane bioreactor (MBR) systems to remove organic micropollutants was investigated at different scales, operational conditions, and locations. The effluent quality of the MBR system was compared with that of a plant combining conventional activated sludge (CAS) followed by ultrafiltration (UF). The MBR and CAS-UF systems were operated and tested in parallel. An MBR pilot plant in Israel was operated for over a year at a mixed liquor suspended solids (MLSS) range of 2.8–10.6 g/L. The MBR achieved removal rates comparable to those of a CAS-UF plant at the Tel-Aviv wastewater treatment plant (WWTP) for macrolide antibiotics such as roxythromycin, clarithromycin, and erythromycin and slightly higher removal rates than the CAS-UF for sulfonamides. A laboratory scale MBR unit in Berlin – at an MLSS of 6–9 g/L – showed better removal rates for macrolide antibiotics, trimethoprim, and 5-tolyltriazole compared to the CAS process of the Ruhleben sewage treatment plant (STP) in Berlin when both were fed with identical quality raw wastewater. The Berlin CAS exhibited significantly better benzotriazole removal and slightly better sulfamethoxazole and 4-tolyltriazole removal than its MBR counterpart. Pilot MBR tests (MLSS of 12 g/L) in Aachen, Germany, showed that operating flux significantly affected the resulting membrane fouling rate, but the removal rates of dissolved organic matter and of bisphenol A were not affected.

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Trace organics removal using three membrane bioreactor configurations: MBR, IFAS-MBR and MBMBR

Water Science & Technology ◽

10.2166/wst.2015.028 ◽

2015 ◽

Vol 71 (5) ◽

pp. 761-768 ◽

Cited By ~ 16

Author(s):

T. de la Torre ◽

E. Alonso ◽

J. L. Santos ◽

C. Rodríguez ◽

M. A. Gómez ◽

...

Keyword(s):

Activated Sludge ◽

Membrane Bioreactor ◽

Municipal Wastewater ◽

Removal Rate ◽

Treatment Plant ◽

Operating Conditions ◽

Removal Rates ◽

Linear Alkylbenzene ◽

Conventional Activated Sludge ◽

Attached Biomass

Seventeen pharmaceutically active compounds and 22 other trace organic pollutants were analysed regularly in the influent and permeate from a semi-real plant treating municipal wastewater. The plant was operated during 29 months with different configurations which basically differed in the type of biomass present in the system. These processes were the integrated fixed-film activated sludge membrane bioreactor (IFAS-MBR), which combined suspended and attached biomass, the moving bed membrane bioreactor (MBMBR) (only attached biomass) and the MBR (only suspended biomass). Moreover, removal rates were compared to those of the wastewater treatment plant (WWTP) operating nearby with conventional activated sludge treatment. Reverse osmosis (RO) was used after the pilot plant to improve removal rates. The highest elimination was found for the IFAS-MBR, especially for hormones (100% removal); this was attributed to the presence of biofilm, which may lead to different conditions (aerobic–anoxic–anaerobic) along its profile, which increases the degradation possibilities, and also to a higher sludge age of the biofilm, which allows complete acclimation to the contaminants. Operating conditions played an important role, high mixed liquor suspended solids (MLSS) and sludge retention time (SRT) being necessary to achieve these high removal rates. Although pharmaceuticals and linear alkylbenzene sulfonates showed high removal rates (65–100%), nonylphenols and phthalate could only be removed to 10–30%. RO significantly increased removal rates to 88% mean removal rate.

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LCA of a Membrane Bioreactor Compared to Activated Sludge System for Municipal Wastewater Treatment

Membranes ◽

10.3390/membranes10120421 ◽

2020 ◽

Vol 10 (12) ◽

pp. 421

Author(s):

Dimitra C. Banti ◽

Michail Tsangas ◽

Petros Samaras ◽

Antonis Zorpas

Keyword(s):

Wastewater Treatment ◽

Life Cycle ◽

Activated Sludge ◽

Membrane Bioreactor ◽

Municipal Wastewater ◽

Wastewater Treatment Plants ◽

Treatment Plant ◽

Real Data ◽

Municipal Wastewater Treatment ◽

Conventional Activated Sludge

Membrane bioreactor (MBR) systems are connected to several advantages compared to the conventional activated sludge (CAS) units. This work aims to the examination of the life cycle environmental impact of an MBR against a CAS unit when treating municipal wastewater with similar influent loading (BOD = 400 mg/L) and giving similar high-quality effluent (BOD < 5 mg/L). The MBR unit contained a denitrification, an aeration and a membrane tank, whereas the CAS unit included an equalization, a denitrification, a nitrification, a sedimentation, a mixing, a flocculation tank and a drum filter. Several impact categories factors were calculated by implementing the Life Cycle Assessment (LCA) methodology, including acidification potential, eutrophication potential, global warming potential (GWP), ozone depletion potential and photochemical ozone creation potential of the plants throughout their life cycle. Real data from two wastewater treatment plants were used. The research focused on two parameters which constitute the main differences between the two treatment plants: The excess sludge removal life cycle contribution—where GWPMBR = 0.50 kg CO2-eq*FU−1 and GWPCAS = 2.67 kg CO2-eq*FU−1 without sludge removal—and the wastewater treatment plant life cycle contribution—where GWPMBR = 0.002 kg CO2-eq*FU−1 and GWPCAS = 0.14 kg CO2-eq*FU−1 without land area contribution. Finally, in all the examined cases the environmental superiority of the MBR process was found.

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Removal of endocrine disrupter compounds from municipal wastewater by an innovative biological technology

Water Science & Technology ◽

10.2166/wst.2008.711 ◽

2008 ◽

Vol 58 (4) ◽

pp. 953-956 ◽

Cited By ~ 21

Author(s):

L. Balest ◽

G. Mascolo ◽

C. Di Iaconi ◽

A. Lopez

Keyword(s):

Activated Sludge ◽

Biological Treatment ◽

Municipal Wastewater ◽

Sewage Treatment Plant ◽

Treatment Plant ◽

Municipal Sewage ◽

Activated Sludge Process ◽

Endocrine Disrupter ◽

Conventional Activated Sludge ◽

Conventional Activated Sludge Process

The removal of selected endocrine disrupter compounds (EDCs), namely estrone(E1), 17β-estradiol (E2), 17α-ethynylestradiol (EE2), bisphenol A (BPA) and 4-tert-octylphenol (4t-OP) from municipal wastewater was investigated using a sequencing batch biofilter granular reactor (SBBGR), a new system for biological treatment based on aerobic granular biomass. This new biological treatment is characterized by high biomass concentration (up to 40 g/L), high sludge retention times (up to 6 months) and low sludge production (i.e., an order of magnitude lower than commonly reported for conventional biological technologies). The investigation was carried out comparing a demonstration SBBGR system with a conventional full-scale activated sludge process. Results showed that the SBBGR performed better than a conventional activated sludge process in removing E1, E2, BPA and 4t-OP. In fact, the average removal percentages of the above mentioned EDCs, obtained during a four month operating period, were 62.2, 68, 91.8, 77.9% and 56.4, 36.3, 71.3, 64.6% for the demonstrative SBBGR system and the conventional activated sludge process of the municipal sewage treatment plant, respectively

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Proof of concept for a new energy-positive wastewater treatment scheme

Water Science & Technology ◽

10.2166/wst.2014.436 ◽

2014 ◽

Vol 70 (10) ◽

pp. 1709-1716 ◽

Cited By ~ 24

Author(s):

C. Remy ◽

M. Boulestreau ◽

B. Lesjean

Keyword(s):

Organic Matter ◽

Energy Balance ◽

Activated Sludge ◽

Municipal Wastewater ◽

Treatment Plant ◽

Anaerobic Sludge ◽

Stable Operation ◽

Conventional Activated Sludge ◽

Pilot Trials ◽

Activated Sludge Processes

For improved exploitation of the energy content present in the organic matter of raw sewage, an innovative concept for treatment of municipal wastewater is tested in pilot trials and assessed in energy balance and operational costs. The concept is based on a maximum extraction of organic matter into the sludge via coagulation, flocculation and microsieving (100 μm mesh size) to increase the energy recovery in anaerobic sludge digestion and decrease aeration demand for carbon mineralisation. Pilot trials with real wastewater yield an extraction of 70–80% of total chemical oxygen demand into the sludge while dosing 15–20 mg/L Al and 5–7 mg/L polymer with stable operation of the microsieve and effluent limits below 2–3 mg/L total phosphorus. Anaerobic digestion of the microsieve sludge results in high biogas yields of 600 NL/kg organic dry matter input (oDMin) compared to 430 NL/kg oDMin for mixed sludge from a conventional activated sludge process. The overall energy balance for a 100,000 population equivalent (PE) treatment plant (including biofilter for post-treatment with full nitrification and denitrification with external carbon source) shows that the new concept is an energy-positive treatment process with comparable effluent quality than conventional processes, even when including energy demand for chemicals production. Estimated operating costs for electricity and chemicals are in the same range for conventional activated sludge processes and the new concept.

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Membrane Fouling Potential of Secondary Effluent Organic Matter (EfOM) from Conventional Activated Sludge Process

Journal of Membrane and Separation Technology ◽

10.6000/1929-6037.2012.01.02.7 ◽

2012 ◽

Cited By ~ 2

Author(s):

Wei

Keyword(s):

Organic Matter ◽

Activated Sludge ◽

Membrane Fouling ◽

Secondary Effluent ◽

Activated Sludge Process ◽

Effluent Organic Matter ◽

Conventional Activated Sludge ◽

Conventional Activated Sludge Process

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Process evaluation of HASP with IMET system through SNR and SDNR for the efficient management of Sewage Treatment Plant

Water Practice & Technology ◽

10.2166/wpt.2008.024 ◽

2008 ◽

Vol 3 (1) ◽

Author(s):

Young H. Yoon ◽

Jae R. Park ◽

Sang W. Ahn ◽

Kwang B. Ko ◽

Kyung J. Min ◽

...

Keyword(s):

Activated Sludge ◽

Linear Regression Analysis ◽

Sewage Treatment Plant ◽

Treatment Plant ◽

Reaction Rates ◽

Nitrification Rate ◽

Activated Sludge Process ◽

Type Experiment ◽

Batch Type ◽

Nitrification And Denitrification

Hybrid Activated Sludge Process (HASP) with IMET was developed and applied to an activated sludge process for the advanced nutrient treatment in Korea. The characteristics of nitrogen removal from the HASP were investigated through a kinetic study by batch-type experiment. Online DB analysis produced from the IMET was conducted for the nutrient removal performance in the field demonstration plant treating 10,000 m3/day in G city of Korea. In this paper, we aimed to determine the effect of increasing NHM4+-N load on the specific nitrification rate (SNR) and the specific denitrification rate (SDNR) through a batch-type experiment, and to estimate the net reaction time for the phase-transfer rate using online DB analysis in the HASP operation. Experimental results include: (1) both the nitrification and denitrification followed first-order kinetics; (2) the maximum SNR and SDNR were 4.0301 mgN/gVSS·hr and 2.785 mgN/gVSS·hr, respectively; (3) comparison of reaction rates between nitrification and denitrification from the non-linear regression analysis found that nitrification rate was higher than denitrification.

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Suivi du fonctionnement d'une station d'epuration associant physico-chimie et biofiltration = Metabief (France)

Water Science & Technology ◽

10.2166/wst.1990.0151 ◽

1990 ◽

Vol 22 (1-2) ◽

pp. 251-259 ◽

Cited By ~ 1

Author(s):

R. Pujol

Keyword(s):

Organic Matter ◽

Biological Process ◽

Sewage Treatment ◽

Sewage Treatment Plant ◽

Treatment Plant ◽

Cold Temperatures ◽

Biological Sludge ◽

Physico Chemical ◽

Total Plant ◽

Sludge Characteristic

The sewage treatment plant of Metabief (East of France) has been monitored during three weeks in winter 1988. The treatment associates a physico-chemical treatment with a biological process of biofiltration. The first step eliminates about 60 % of the organic matter (COD and BOD). The biofliters improve the treatment removing 60 % of COD influent and 65 % of TSS. The process is efficient (N excepted) under conditions of the experiment but nitrification is limited by cold temperatures (< 10°C). Important results related to biological sludge product are presented (sludge characteristic, microscopic data, sludge production). Power consumption of biofliters represents 70 % of the total plant needs. Adequate control of washing cycles and close survey of numerous movable devices are of the utmost importance to guarantee the proper operating of biofliters.

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System Identification and Control of the Activated Sludge Process by Use of a Statistical Model

Water Science & Technology ◽

10.2166/wst.1989.0316 ◽

1989 ◽

Vol 21 (10-11) ◽

pp. 1161-1172 ◽

Cited By ~ 8

Author(s):

M. Hiraoka ◽

K. Tsumura

Keyword(s):

Control System ◽

System Identification ◽

Statistical Model ◽

Activated Sludge ◽

Sewage Treatment Plant ◽

Treatment Plant ◽

Ar Model ◽

Diurnal Changes ◽

Activated Sludge Process ◽

And Control

The authors have been developing a hierarchical control system for the activated sludge process which consists of an upper level system controlling long-term seasonal variations, a control system of intermediate level aiming at optimization of the process and a control system of lower level controlling diurnal changes or hourly fluctuations. The control system using the multi-variable statistical model is one of the most appropriate control systems based on the modern control theory, for applying the lower level control of the activated sludge process. This paper introduces our efforts for developing the reliable data acquisition system, the control experiments applying the AR-model, one of the statistical models which were conducted at a pilot plant and present studies on the system identification and control at a field sewage treatment plant.

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High rate and compact single sludge pre-denitrification process for retrofit

Water Science & Technology ◽

10.2166/wst.1994.0250 ◽

1994 ◽

Vol 30 (6) ◽

pp. 31-40 ◽

Cited By ~ 11

Author(s):

Hiroyshi Emori ◽

Hiroki Nakamura ◽

Tatsuo Sumino ◽

Tadashi Takeshima ◽

Katsuzo Motegi ◽

...

Keyword(s):

Activated Sludge ◽

Sewage Treatment ◽

Treatment Plant ◽

High Rate ◽

Activated Sludge Process ◽

Nitrogen And Phosphorus ◽

Conventional Activated Sludge ◽

Treatment Techniques ◽

Conventional Activated Sludge Process ◽

Denitrification Process

For the sewage treatment plants near rivers and closed water bodies in urbanized areas in Japan and European countries, there is a growing demand for introduction of advanced treatment processes for nitrogen and phosphorus from the viewpoints of water quality conservation and environmental protection. In order to remove nitrogen by the conventional biological treatment techniques, it is necessary to make a substantial expansion of the facility as compared with the conventional activated sludge process. In such urbanized districts, it is difficult to secure a site and much capital is required to expand the existing treatment plant. To solve these problems, a compact single sludge pre-denitrification process using immobilized nitrifiers was developed. Dosing the pellets, which are suitable for nitrifiers growth and physically durable, into the nitrification tank of single sludge pre-denitrification process made it possible to perform simultaneous removal of BOD and nitrogen in a retention time equal to that in the conventional activated sludge process even at the low water temperature of about 10 °C. The 3,000 m3/d full-scale conventional activated sludge plant was retrofitted and has been successfully operated.

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