Decentralized wastewater treatment using ‘Pumped Flow Biofilm Reactor’ (PFBR) technology

2016 ◽  
Vol 11 (1) ◽  
pp. 93-103 ◽  
Author(s):  
Shane Fox ◽  
Michael Cahill ◽  
Edmond O'Reilly ◽  
Eoghan Clifford
Keyword(s):  
Wastewater Treatment ◽  
Municipal Wastewater ◽  
New Technologies ◽  
Phase 1 ◽  
Oxygen Demand ◽  
Biofilm Reactor ◽  
Small Scale ◽  
Mechanical Equipment ◽  
Phase 2 ◽  
Sludge Production

Clean water resources are imperative for sustainable development. Thus, protection and management of waters receiving wastewater discharges have received significant attention from policy and regulatory bodies. The quality of wastewater effluent must meet regional (e.g. Water Framework Directive), national and local discharge standards. In addition, there is now significant pressure on engineers and operators to reduce energy consumption, sludge production and operation/maintenance issues, particularly at small-scale and decentralized wastewater facilities. Therefore, significant interest has risen in new technologies and operational insights which can (i) minimize operating costs; (ii) simplify and reduce the use of mechanical equipment; (iii) result in low sludge production; and (iv) ease operation/maintenance. This study investigated the performance of a small-scale municipal wastewater facility over 5 months from commissioning. The facility uses a new biofilm-based technology – the pumped flow biofilm reactor. Two experimental periods Phase 1 (28 to 36 days) and Phase 2 (Days 100 to 146) were examined. During Phase 2, removal rates averaged 98% for 5-day biochemical oxygen demand (BOD5), 93% for total suspended solids, and 94% ammoniacal-nitrogen (NH4-N). Energy requirements averaged 0.22 kWh.m treated−3 and 1.74 kWh.kg-BOD5 removed−1. Extensive, camera-based studies revealed minimal excess sludge in the reactor tanks and sludge removal was not required during the study period. The use of vertically stacked plastic media to support the biofilm may have limited biofilm sloughing. Sludge yield during steady state operation was estimated at around 0.03 g-SS.g-COD removed−1. The study indicates that given careful design and operation, small-scale wastewater treatment systems can be as efficient as much larger, fully manned plants.

scholarly journals Improving and upgrading an existing activated sludge with a compact MBBR – disc filters parallel line for municipal wastewater treatment in touristic alpine areas

2020 ◽  
Vol 15 (2) ◽  
pp. 515-527
Author(s):  
L. Desa ◽  
P. Kängsepp ◽  
L. Quadri ◽  
G. Bellotti ◽  
K. Sørensen ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Municipal Wastewater ◽  
Wastewater Treatment Plants ◽  
Oxygen Demand ◽  
Parallel Line ◽  
Ammonium Nitrogen ◽  
Biofilm Reactor ◽  
Municipal Wastewater Treatment ◽  
Yearly Average

Abstract Many wastewater treatment plants (WWTP) in touristic areas struggle to achieve the effluent requirements due to seasonal variations in population. In alpine areas, the climate also determines a low wastewater temperature, which implies long sludge retention time (SRT) needed for the growth of nitrifying biomass in conventional activated sludge (CAS). Moreover, combined sewers generate high flow and dilution. The present study shows how the treatment efficiency of an existing CAS plant with tertiary treatment can be upgraded by adding a compact line in parallel, consisting of a Moving Bed Biofilm Reactor (MBBR)-coagulation-flocculation-disc filtration. This allows the treatment of influent variations in the MBBR and a constant flow supply to the activated sludge. The performance of the new 2-step process was comparable to that of the improved existing one. Regardless significant variations in flow (10,000–25,000 m3/d) and total suspended solids (TSS) (50–300 mg/L after primary treatment) the effluent quality fulfilled the discharge requirements. Based on yearly average effluent data, TSS were 11 mg/L, chemical oxygen demand (COD) 27 mg/L and total phosphorus (TP) 0.8 mg/L. After the upgrade, ammonium nitrogen (NH4-N) dropped from 4.9 mg/L to 1.3 mg/L and the chemical consumption for phosphorus removal was reduced.

Sludge production characteristics of small-scale wastewater treatment facilities using anaerobic/aerobic biofilm reactors

1996 ◽  
Vol 34 (3-4) ◽  
pp. 379-387 ◽  
Author(s):  
Yuhei Inamori ◽  
Tomotake Takai ◽  
Yasuhiro Yamamoto ◽  
Nobuyoshi Katagai ◽  
Toshihiro Sankai ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Plug Flow ◽  
Biofilm Reactor ◽  
Small Scale ◽  
Constant Flow Rate ◽  
Loading Rates ◽  
Circulation Ratio ◽  
Treatment Facilities ◽  
Production Characteristics ◽  
Sludge Production

Sludge production characteristics were investigated in many on-site small-scale wastewater treatment facilities used to treat domestic wastewater of about 1.25m3/day. Two popular types have been used in experiments for several years; one was an anaerobic bed reactor with constant flow-rate control system followed by aerobic bio-filtration reactor CFR type facility), and the other was an aerobic bed reactor with plug-flow stream followed by aerobic biofilm reactor (PFS type facility). Circulation ratio was set at 0 and 4. From the results obtained, lower sludge production rates were observed in CFR type facilities. Furthermore, it was suggested that a promotion of sludge decrease occurred in facilities with high denitrification activity at circulation ratio of 4. The results from experiments with different SS loading rates in laboratory-scale reactors suggested that at higher loading rates, the produced sludge was greater on account of the decrease of nitrification activity even on a circulating operation.

Pumped flow biofilm reactors (PFBR) for treating municipal wastewater

2008 ◽  
Vol 57 (12) ◽  
pp. 1857-1865 ◽  
Author(s):  
E. O'Reilly ◽  
M. Rodgers ◽  
X.-M. Zhan
Keyword(s):  
Wastewater Treatment ◽  
Surface Area ◽  
Municipal Wastewater ◽  
Treatment Plant ◽  
Cross Flow ◽  
Oxygen Demand ◽  
Pilot Scale ◽  
Ammonium Nitrogen ◽  
Biofilm Reactor ◽  
Bench Scale

A novel laboratory bench-scale sequencing batch biofilm reactor (SBBR) system was developed for the treatment of synthetic domestic strength wastewater, comprising two side-by-side 18 l reactor tanks, each containing a plastic biofilm media module. Aerobic and anoxic conditions in the biofilms were effected by intermittent alternate pumping of wastewater between the two reactors. With a media surface area loading rate of 4.2 g chemical oxygen demand (COD)/m2.d, the average influent COD, total nitrogen (TN) and ammonium-nitrogen (NH4-N) concentrations of 1021 mg/l, 97 mg/l and 54 mg/l, respectively, reduced to average effluent concentrations of 72 mg COD/l, 17.8 mg TN/l, and 5.5 mg NH4-N /l. Using a similar alternating biofilm exposure arrangement, a 16 person equivalent pilot (PE) plant was constructed at a local village treatment works to remove organic carbon from highly variable settled municipal wastewater and comprised two reactors, one positioned above the other, each containing a module of cross-flow plastic media with a surface area of 100 m2. Two different pumping sequences (PS) in the aerobic phase were examined where the average influent COD concentrations were 220 and 237 mg/l for PS1 and PS2, respectively, and the final average effluent COD was consistently less than 125 mg/l – the European Urban Wastewater Treatment Directive limit – with the best performance occurring in PS1. Nitrification was evident during both PS1 and PS2 studies. A 300 PE package treatment plant was designed based on the bench-scale and pilot-scale studies, located at a local wastewater treatment works and treated municipal influent with average COD, suspended solids (SS) and TN concentrations of 295, 183 and 15 mg/l, respectively resulting in average effluent concentrations of 67 mg COD/l, 17 mg SS/l and 9 mg TN/l. The SBBR systems performed well, and were simple to construct and operate.

Qualitative evaluation of small scale municipal Wastewater Treatment Plants (WWTPs) in South India

2015 ◽  
Vol 10 (4) ◽  
pp. 711-719 ◽  
Author(s):  
S. Suneethi ◽  
G. Keerthiga ◽  
R. Soundhar ◽  
M. Kanmani ◽  
T. Boobalan ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
South India ◽  
Municipal Wastewater ◽  
Energy Requirement ◽  
Biofilm Reactor ◽  
Plant Performance ◽  
Small Scale ◽  
Treatment Technology ◽  
Natural Treatment ◽  
Treatment Technologies

Decentralized wastewater treatment system (DEWATS) are widely used for the treatment of wastewater originating from residences, institutes and municipalities, specifically in South India. Most of these STPs are denounced owing to failures on several fronts including design, operation and maintenance, installation and monitoring. A comprehensive review and evaluation of STPs was timely, in order to derive sound conclusions and recommendations for future wastewater management strategies. The objective of the present study was to conduct an independent evaluation of already existing decentralized STPs in South India. The technologies assessed were Aerated lagoon (AL), Extended aeration (EA), Anaerobic filter/Vortex put forward by Centre for Scientific Research (CSR VORTEX), Constructed Wetland (DEWATS others), Membrane bioreactor (MBR) and Moving bed Biofilm reactor (MBBR). Among the various technologies evaluated, MBR exhibited the highest total COD, BOD and solids removal efficiency. Pathogen count was lowest in MBR, followed by MBBR and AL. Nutrient removal in terms of ammoniacal nitrogen and nitrate nitrogen was highest in DEWATS. Effective hours of continuous operation enabled improved plant performance. In case of natural treatment technology such as DEWATS, energy requirement is quite low, whereas conventional treatment technologies such as EA necessitate considerably high demand of energy, requiring few personnel to operate the system. Innovative high cell density systems such as MBBR and MBR entail significant power consumption and elaborate maintenance, requiring large number of skilled professionals. The major reasons for failure of STPs were related to mechanical, electrical and labour problems. Regular monitoring and maintenance is required with due diligence in all the treatment technologies for proper functioning.

scholarly journals Optimization of sequencing batch reactor for wastewater treatment using chemically enhanced primary treatment as a pre-treatment

Water SA ◽  
2018 ◽  
Vol 44 (3 July) ◽  
Author(s):  
Haroon R Mian ◽  
Sajjad Haydar ◽  
Ghulam Hussain ◽  
Gul -e-Hina
Keyword(s):  
Wastewater Treatment ◽  
Reaction Time ◽  
Sequencing Batch Reactor ◽  
Batch Reactor ◽  
Phase 1 ◽  
Oxygen Demand ◽  
Scale Model ◽  
Phase 2 ◽  
Removal Efficiencies ◽  
Raw Wastewater

The sequencing batch reactor (SBR) is a wastewater treatment option feasible for low flows. The objective of this research was to optimize SBR by varying its operational parameters, viz. (i) settling time and (ii) reaction time. The study was conducted in two phases. In Phase 1, raw wastewater was fed into the SBR after conventional settling, while in Phase 2 raw wastewater was fed into the SBR after coagulation-flocculation-sedimentation. A bench-scale model was set up and domestic wastewater was used for this study. Performance of the treatment system was evaluated through 5-day biochemical oxygen demand (BOD), chemical oxygen demand (COD) and total suspended solids (TSS). The results demonstrated that reaction time was reduced to 4 h in Phase 2 compared to 10 h in Phase 1. The BOD, COD and TSS removal efficiencies observed in Phase 1 were 80%, 80% and 73%, respectively, and for Phase 2 the removal efficiencies were 74%, 75% and 80% respectively. National Environmental Quality Standards (NEQS) were met in both cases and the treatment cost per cubic metre of wastewater for Phase 2 was 2.5 times lower compared to Phase 1.

scholarly journals Integration of Forward Osmosis in Municipal Wastewater Treatment Applications

2021 ◽  
Author(s):  
Stavroula Kappa ◽  
Simos Malamis
Keyword(s):  
Wastewater Treatment ◽  
Membrane Fouling ◽  
Municipal Wastewater ◽  
New Technologies ◽  
Energy Content ◽  
Forward Osmosis ◽  
Treatment Plant ◽  
Oxygen Demand ◽  
Municipal Wastewater Treatment ◽  
Reverse Salt Flux

In recent years, the research community has made constant efforts to develop new technologies for the recovery and valorization of water, nutrient and energy content of municipal wastewater. However, the recovery process is significantly limited due to the low-strength of sewage. Over the last 10 years, the Forward Osmosis (FO) process, has gained interest as a low-cost process with low membrane fouling propensity, which can convert municipal wastewater into a concentrated low-volume effluent, characterized by high organic and nutrient concentration. This chapter presents the main configurations that have been implemented for the concentration of municipal wastewater using FO, including their performance in terms of contaminant removal and water/reverse salt flux (Jw/Js). Furthermore, the draw solutions and respective concentrations that have been used in FO for the treatment of sewage are reported, while at the same time the positive and negative characteristics of each application are evaluated. Finally, in the last section of this chapter, the spontaneous FO followed by anaerobic process is integrated in a municipal wastewater treatment plant (WWTP) and compared with a conventional one. The comparison is done, in terms of the mass balance of the chemical oxygen demand (COD) and in terms of the energy efficiency.

Floc size distribution and bacterial activities in membrane separation activated sludge processes for small-scale wastewater treatment/reclamation

1997 ◽  
Vol 35 (6) ◽  
pp. 37-44 ◽  
Author(s):  
Boran Zhang ◽  
Kazuo Yamamoto ◽  
Shinichiro Ohgaki ◽  
Naoyuki Kamiko
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Municipal Wastewater ◽  
Membrane Separation ◽  
Small Scale ◽  
Nitrification Rate ◽  
Floc Size ◽  
Denitrification Activity ◽  
Concentration Changes ◽  
Activated Sludge Processes

Activated sludges taken from full-scale membrane separation processes, building wastewater reuse system (400m3/d), and two nightsoil treatment plants (50m3/d) as well as laboratory scale membrane separation bioreactor (0.062m3/d) were analyzed to characterize membrane separation activated sludge processes (MSAS). They were also compared with conventional activated sludges(CAS) taken from municipal wastewater treatment plants. Specific nitrification activity in MSAS processes averaged at 2.28gNH4-N/kgMLSS.h were higher than that in CAS processes averaged at 0.96gNH4-N/kgMLSS.h. The denitrification activity in both processes were in the range of 0.62-3.2gNO3-N/kgMLSS.h without organic addition and in the range of 4.25-6.4gNO3-N/kgMLSS.h with organic addition. The organic removal activity in nightsoil treatment process averaged at 123gCOD/kgMLSS.h which was significantly higher than others. Floc size distributions were measured by particle sedimentation technique and image analysis technique. Flocs in MSAS processes changed their sizes with MLSS concentration changes and were concentrated at small sizes at low MLSS concentration, mostly less than 60 μm. On the contrary, floc sizes in CAS processes have not much changed with MLSS concentration changes and they were distributed in large range. In addition, the effects of floc size on specific nitrification rate, denitrification rate with and without organic carbon addition were investigated. Specific nitrification rate was decreased as floc size increased. However, little effect of floc size on denitrification activity was observed.

Novel biofilm reactor for denitrification of municipal wastewater

2018 ◽  
Vol 78 (7) ◽  
pp. 1566-1575 ◽  
Author(s):  
S. S. Rathnaweera ◽  
B. Rusten ◽  
K. Korczyk ◽  
B. Helland ◽  
E. Rismyhr
Keyword(s):  
Carbon Source ◽  
Municipal Wastewater ◽  
Low Cost ◽  
Oxygen Demand ◽  
Pilot Scale ◽  
Biofilm Reactor ◽  
Treated Wastewater ◽  
Removal Rates ◽  
Good Filter ◽  
Solids Removal

Abstract A pilot-scale CFIC® (continuous flow intermittent cleaning) reactor was run in anoxic conditions to study denitrification of wastewater. The CFIC process has already proven its capabilities for biological oxygen demand removal with a small footprint, less energy consumption and low cost. The present study focused on the applicability for denitrification. Both pre-denitrification (pre-DN) and post-denitrification (post-DN) were tested. A mixture of primary treated wastewater and nitrified wastewater was used for pre-DN and nitrified wastewater with ethanol as a carbon source was used for post-DN. The pre-DN process was carbon limited and removal rates of only 0.16 to 0.74 g NOx-N/m²-d were obtained. With post-DN and an external carbon source, 0.68 to 2.2 g NO3-Neq/m²-d removal rates were obtained. The carrier bed functioned as a good filter for both the larger particles coming with influent water and the bio-solids produced in the reactor. Total suspended solids removal in the reactor varied from 20% to 78% (average 45%) during post-DN testing period and 9% to 70% (average 29%) for pre-DN. The results showed that the forward flow washing improves both the DN function and filtration ability of the reactor.

scholarly journals Municipal Wastewater Treatment Using a Packed Bio-tower Approach

2020 ◽  
pp. 42-50
Author(s):  
Klaus Doelle ◽  
Qian Wang
Keyword(s):  
Wastewater Treatment ◽  
Flow Rate ◽  
Municipal Wastewater ◽  
Oxygen Demand ◽  
Pilot Scale ◽  
Continuous Operation ◽  
Growth Media ◽  
Municipal Wastewater Treatment ◽  
Bacteria Growth ◽  
Tower System

The study tested a designed and built pilot scale packed bio-tower system under continuous operation using pre-clarified municipal wastewater. Performance was evaluated by measuring the removal of chemical oxygen demand and nitrogen ammonia. The pilot scale packed bio-tower system had a diameter of 1209 mm (4 ft.) and a height of 3,962 mm (13 ft.) and contained Bentwood CF-1900 bacteria growth media with a surface area of 6,028.80 ft² (560.09 m²). The municipal residential sewage was fed into a 1,481 l (375 gal.) recirculation reservoir at a temperature of 15°C (59.0°F) and a flow rate between 7,571 l/d (2000 gal/d) and 90,850 l/d (24,000 gal/d) and recirculated through the bio-tower with a fixed recirculation rate of 75.7 l/min (20 gal/min). The influent COD value reduction achieved is between 63.4% and 84.8%, whereas the COD influent value varied between 87 mg/l and 140 mg/l. The influent NH3-N reduction achieved was between 99.8% and 91.8% whereas the influent NH3-N value was between 28.8 mg/l and 18.6 mg/l  at a flow rate between 7571 l/d (2000 gal/d) and 90,850 l/d (24,000 gal/d).

Sign in / Sign up

Export Citation Format

Share Document