Costs of tertiary treatment of municipal wastewater by rapid sand filter with coagulants and UV

2003 ◽  
Vol 3 (4) ◽  
pp. 145-152 ◽  
Author(s):  
H. Heinonen-Tanski ◽  
P. Juntunen ◽  
R. Rajala ◽  
E. Haume ◽  
A. Niemelä
Keyword(s):  
Total Phosphorus ◽  
Municipal Wastewater ◽  
Pilot Scale ◽  
Treated Wastewater ◽  
Tertiary Treatment ◽  
Sand Filter ◽  
Physico Chemical ◽  
Bathing Waters ◽  
Filtration Unit ◽  
Microbial Groups

Municipal treated wastewater has been tertiary treated in a pilot-scale rapid sand filter. The filtration process was improved by using polyaluminium coagulants. The sand-filtered water was further treated with one or two UV reactors. The quality changes of wastewater were measured with transmittance, total phosphorus, soluble phosphorus, and somatic coliphages, FRNA-coliphages, FC, enterococci and fecal clostridia. Sand filtration alone without coagulants improved slightly some physico-chemical parameters and it had almost no effect on content of microorganisms. If coagulants were used, the filtration was more effective. The reductions were 88-98% for microbial groups and 80% for total phosphorus. The wastewater would meet the requirements for bathing waters (2,000 FC/100 ml, EU, 1976). UV further improved the hygiene level; this type of treated wastewater could be used for unrestricted irrigation (2.2 TC/100 ml, US.EPA 1992). The improvement was better if coagulants were used. The price for tertiary treatment (filtration + UV) would have been 0.036 Euro/m3 according to prices in 2001 in 22 Mm3/a. The investment cost needed for the filtration unit was 0.020 Euro/m3 (6%/15a). Filtration with coagulants is recommended in spite of its costs, since the low transmittance of unfiltered wastewater impairs the efficiency of the UV treatment.

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.

A pilot scale study of a sequencing batch reactor treating municipal wastewater operated via the UP-PND process

2008 ◽  
Vol 58 (2) ◽  
pp. 435-438 ◽  
Author(s):  
M. Kornaros ◽  
C. Marazioti ◽  
G. Lyberatos
Keyword(s):  
Wastewater Treatment ◽  
Municipal Wastewater ◽  
Batch Reactor ◽  
Treatment Plant ◽  
Pilot Scale ◽  
Treated Wastewater ◽  
Synthetic Wastewater ◽  
Second Step ◽  
Decentralized Wastewater Treatment ◽  
Real Wastewater

SBRs are usually preferred as small and decentralized wastewater treatment systems. We have demonstrated previously that using a frequent enough switching between aerobic and anoxic conditions and a specific to the treated wastewater aerobic to anoxic phase ratio, it is possible to by-pass the second step of nitrification (i.e. conversion of nitrite to nitrate nitrogen). This innovative process for nitrate by-pass has been branded as UP-PND (University of Patras-Partial Nitrification Denitrification) (WO 2006/129132). The proved methodology was successfully transferred from a lab-scale SBR reactor treating synthetic wastewater to a pilot-scale SBR system treating real wastewater. In this work we present the results from the operation of this pilot-scale SBR, constructed in the Wastewater Treatment Plant of Patras (Greece), using 6-hour, 8-hour and 12-hour cycles. It is demonstrated that three pairs of aerobic/anoxic phases with a relative duration of 1:2 (8-hour cycle) and 2:3 (12-hour cycle) secures the desired by-pass of nitrate production.

Deep-bed filtration of SBR effluent for agricultural reuse: pilot plant screening of advanced secondary and tertiary treatment for domestic wastewater

1994 ◽  
Vol 30 (9) ◽  
pp. 219-227 ◽  
Author(s):  
Asher Brenner ◽  
Semen Shandalov ◽  
Gideon Oron ◽  
Menahem Rebhun
Keyword(s):  
Batch Reactor ◽  
Groundwater Resources ◽  
Domestic Wastewater ◽  
Water Shortage ◽  
Pilot Scale ◽  
Treated Wastewater ◽  
Wastewater Reclamation ◽  
Tertiary Treatment ◽  
Granular Filtration ◽  
Single Medium

A wastewater reclamation program has been proposed as a means of supplying a major part of agricultural water demand in Israel. This program may solve the two fold problem of a national water shortage combined with continuous contamination of groundwater resources by inadequately treated wastewater. A pilot-scale investigation of an advanced treatment scheme incorporating a sequencing batch activated sludge system, followed by deep-bed granular filtration, has been started. It is aimed at the development of design and operation guidelines for such systems to be applied on a full scale. Preliminary results presented herein indicate that the sequencing batch reactor system is capable of producing high-quality, low-suspended-solids effluent to be further polished by granular filtration. A single medium quartz sand filter operated under a high variety of filtration velocities and inflow turbidities with no chemicals added, demonstrated good performance and supplied basic design information to be applied in further investigation.

Evaluation of moving bed sand filter for denitrification, suspended solids removal and very low effluent total phosphorus concentrations

2019 ◽  
Vol 80 (2) ◽  
pp. 232-242
Author(s):  
S. S. Rathnaweera ◽  
B. Rusten ◽  
L. D. Manamperuma ◽  
J. Gjevre ◽  
I. Tranum
Keyword(s):  
Total Phosphorus ◽  
Nitrogen Removal ◽  
Suspended Solids ◽  
Municipal Wastewater ◽  
Treatment Plant ◽  
Particle Removal ◽  
Sand Filter ◽  
Moving Bed ◽  
Wwtp Effluent ◽  
Final Effluent

Abstract Continuously flushing moving bed sand filter was operated in pilot scale for phosphorus (P) and nitrogen removal with simultaneous particle removal. The wastewater tested was either final effluent from a municipal wastewater treatment plant (WWTP) with nitrogen removal in moving bed biofilm reactors (MBBRs) followed by coagulation and dissolved air flotation (DAF) for P and suspended solids (SS) removal, or different mixtures of this final effluent and effluent from the MBBR-stage. The study focused on the applicability to achieve low total phosphorus (TP) concentrations (below 0.1 mg/L) and suspended solids concentrations (below 10 mg SS/L), plus good denitrification (removal rate over 750 g NO3-N/m3-d), by treating wastewater having variable concentrations of TP (from 0.19 to 7.3 mg/L), SS (from 3 to 169 mg/L) and total nitrogen (from 8 to 27 mg/L). The target effluent TP limit was easily achieved when adding coagulant to WWTP effluent. With correct coagulant dose (Al/TP-molar ratio >4) and good particle removal the target effluent TP could also be reached when treating mixed WW with fairly high influent TP. Very high denitrification rates were achieved with adequate influent P concentration and external carbon source. Low denitrification rates were observed when limited by low concentrations of biodegradable carbon and phosphorus.

scholarly journals Pilot-scale study to investigate the impact of rotating belt filter upstream of a MBR for nitrogen removal

2019 ◽  
Vol 79 (3) ◽  
pp. 458-465
Author(s):  
V. A. Razafimanantsoa ◽  
D. Adyasari ◽  
A. K. Sahu ◽  
B. Rusten ◽  
T. Bilstad ◽  
...  
Keyword(s):  
Organic Matter ◽  
Municipal Wastewater ◽  
Biogas Production ◽  
Oxygen Demand ◽  
Pilot Scale ◽  
Primary Treatment ◽  
Treated Wastewater ◽  
Transmembrane Pressure ◽  
Fine Mesh ◽  
The Impact

Abstract The goal of this study was to investigate what kind of impact the removal of particulate organic matter with 33μm rotating belt filter (RBF) (as a primary treatment) will have on the membrane bioreactor (MBR) performance. Two small MBR pilot plants were operated in parallel, where one train treated 2mm screened municipal wastewater (Train A) and the other train treated wastewater that had passed through a RBF with a 33μm filter cloth (Train B). The RBF was operated without a filter mat on the belt. About one third of the organic matter was removed by the fine mesh filter. The assessment of the overall performance showed that the two pilot plants achieved approximately the same removal efficiencies with regard to total suspended solids (TSS), chemical oxygen demand (COD), total phosphorus and total nitrogen. It was also observed that the system with 33μm RBF as a primary treatment produced more sludge, which could be used for biogas production, and required about 30% less aeration downstream. Transmembrane pressure was significantly lower for the train receiving 33μm primary treated wastewater compared to the control receiving 2mm screened wastewater.

Biological nutrient removal at a very low-loaded activated sludge plant with high biomass concentrations

1998 ◽  
Vol 38 (1) ◽  
pp. 63-70 ◽  
Author(s):  
H. J. Kiuru ◽  
J. A. Rautiainen
Keyword(s):  
Activated Sludge ◽  
Total Nitrogen ◽  
Total Phosphorus ◽  
Nitrogen Removal ◽  
Nutrient Removal ◽  
Municipal Wastewater ◽  
Treated Wastewater ◽  
Biological Nutrient Removal ◽  
Activated Sludge Process ◽  
Biological Phosphorus

The Laboratory of Environmental Engineering at the Helsinki University of Technology (HUT) carried out in 1991-1995 two successive full-scale research and development projects at the Pihlajaniemi WWTP of Savonlinna concerning biological nutrient removal from municipal wastewater. The projects have resulted in two reports in Finnish with quite large English summaries. This WWTP was constructed originally (1978) as a conventional low-loaded activated sludge plant with the simultaneous precipitation of phosphorus. It was dimensioned for a sludge concentration of 3.5 kgMLSS/m3 in the aeration tanks. Six years later (1984) the plant was fitted with a tertiary stage of flotation filters in order to improve the removal of suspended solids and phosphorus. Nitrification was introduced to the activated sludge process of the plant in 1987. It could be done without any extension by using the sludge concentrations of 6-10 kgMLSS/m3 in the aeration tanks. In that way, this activated sludge process was converted into a very low-loaded one. The process became able to nitrify totally in the circumstances in which the wastewater temperature varies at the range of 4-20°C. The actual hydraulic as well as the BOD7-load of the plant are about 40% of the original dimensioned ones. This activated sludge process of the Pihlajaniemi WWTP was modified in 1991-1993 for nitrogen removal and then in 1994-1995 for both biological phosphorus and nitrogen removal Denitrification was introduced to the process and the simultaneous precipitation of phosphorus in that was replaced by biological phosphorus removal still without any extension of the activated sludge process. The plant has now been operated over four years with biological nutrient removal exploiting the organic carbon compounds of the wastewater. A very little addition of some precipitant is used to improve the biological removal of phosphorus. The chemical and energy cost of the plant has been reduced by some 50% due to the introduction of biological nutrient removal. The BOD7-value of the treated wastewater is mainly less than 3 mg/l (always less than 5 mg/l). The content of total phosphorus in the treated wastewater is usually less than 0.3 mg/l (always less than 0.5 mg/l). The content of total nitrogen in the treated wastewater is mainly 8-12 mg/l. Reductions for BOD7 and total phosphorus over 95% as well as that for total nitrogen about 70% are achieved.

A pilot scale comparison of advanced oxidation processes for estrogenic hormone removal from municipal wastewater effluent

2014 ◽  
Vol 70 (1) ◽  
pp. 70-75 ◽  
Author(s):  
Radka Pešoutová ◽  
Luboš Stříteský ◽  
Petr Hlavínek
Keyword(s):  
Advanced Oxidation Processes ◽  
Municipal Wastewater ◽  
Advanced Oxidation ◽  
Endocrine Disrupting Compounds ◽  
Pilot Scale ◽  
Treated Wastewater ◽  
Removal Rates ◽  
Oxidation Processes ◽  
17Β Estradiol ◽  
Hydroxyl Radical Scavengers

This study investigates the oxidation of selected endocrine disrupting compounds (estrone, 17β-estradiol, estriol and 17α-ethinylestradiol) during ozonation and advanced oxidation of biologically treated municipal wastewater effluents in a pilot scale. Selected estrogenic substances were spiked in the treated wastewater at levels ranging from 1.65 to 3.59 μg · L−1. All estrogens were removed by ozonation by more than 99% at ozone doses ≥1.8 mg · L−1. At a dose of 4.4 · mg L−1 ozonation reduced concentrations of estrone, 17β-estradiol, estriol and 17α-ethinylestradiol by 99.8, 99.7, 99.9 and 99.7%, respectively. All tested advanced oxidation processes (AOPs) achieved high removal rates but they were slightly lower compared to ozonation. The lower removal rates for all tested advanced oxidation processes are caused by the presence of naturally occurring hydroxyl radical scavengers – carbonates and bicarbonates.

scholarly journals Prevalence of common enteric viruses in municipal wastewater treatment plants and their health risks arising from wastewater reuse

2021 ◽  
Author(s):  
Peng Liu ◽  
Zihan Li ◽  
Zifan Che ◽  
Hu Xinran ◽  
Ming Ying ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Health Risks ◽  
Municipal Wastewater ◽  
Wastewater Treatment Plants ◽  
Wastewater Reuse ◽  
Enteric Viruses ◽  
Treated Wastewater ◽  
Tertiary Treatment ◽  
Treatment Processes ◽  
Raw Wastewater

Abstract Enteric viruses are known to be prevalent in municipal wastewater, but information on the health risks arising from wastewater reuse is limited. This study quantified six common enteric viruses in raw wastewater and determined the effectiveness of different secondary and tertiary treatment processes at reducing their abundances in three full-scale wastewater treatment plants in China. In the raw wastewater, polyomavirus BK and norovirus GII (Nov GII) exhibited the highest abundance among the detected DNA and RNA viruses, respectively, with concentrations >5 log10 copies/L. Viruses in the raw wastewater were mainly removed by the secondary treatment processes, with log reduction values ranging from 1 to 2. The tertiary treatment processes of both chlorination and ultraviolet irradiation facilitated the additional reduction of viruses. The quantitative microbial risk assessment was applied to estimate the health risks of adenovirus (Adv) and Nov GII when reusing the treated wastewater for irrigation of public green spaces and crops. Estimated disabled-adjusted life-years of Adv and Nov GII for both reuses were higher than the risk threshold (10−6) required by the WHO in the actual scenarios. More effective treatment technologies should be implemented to remove viruses for safe reuse of the treated wastewater.

DECOLOURIZATION AND COD REMOVAL OF WASEWATER FROM ETHANOL PRODUCTION PROCESS FROM MOLASSES BY COAGULANTION USING INORGANIC ALUM

2010 ◽  
Vol 13 (3) ◽  
pp. 92-102
Author(s):  
Trung Duc Le
Keyword(s):  
Ethanol Production ◽  
Oxygen Demand ◽  
Cod Removal ◽  
Treated Wastewater ◽  
Treatment Processes ◽  
Physico Chemical ◽  
Biological Methods ◽  
Treatment Step ◽  
Main Material

The industrial production of ethanol by fermentation using molasses as main material that generates large quantity of wastewater. This wastewater contains high levels of colour and chemical oxygen demand (COD), that may causes serious environmental pollution. Most available treatment processes in Vietnam rely on biological methods, which often fail to treat waste water up to discharge standard. As always, it was reported that quality of treated wastewater could not meet Vietnameses discharge standard. So, it is necessary to improve the treatment efficiency of whole technological process and therefore, supplemental physico-chemical treatment step before biodegradation stage should be the appropriate choice. This study was carried out to assess the effect of coagulation process on decolourization and COD removal in molasses-based ethanol production wastewater using inorganic coaglutant under laboratory conditions. The experimental results showed that the reductions of COD and colour with the utilization of Al2(SO4)3 at pH 9.5 were 83% and 70%, respectively. Mixture FeSO4 – Al2(SO4)3 at pH 8.5 reduced 82% of colour and 70% of COD. With the addition of Polyacrylamide (PAM), the reduction efficiencies of colour, COD and turbidity by FeSO4 – Al2(SO4)3 were 87%, 73.1% and 94.1% correspondingly. It was indicated that PAM significantly reduced the turbidity of wastewater, however it virtually did not increase the efficiencies of colour and COD reduction. Furthermore, the coagulation processes using PAM usually produces a mount of sludge which is hard to be deposited.

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