Wastewater treatment using a vertically moving biofilm system followed by a sand filter

Wastewaters have the potential to proliferate excessive numbers of cyanobacteria due to high nutrient levels. This could translate to the production of metabolites, such as the saxitoxins, geosmin and 2-methylisoborneol (MIB), which can impair the quality of wastewater destined for re-use. Biological sand filtration was assessed for its ability to remove these metabolites from a wastewater. Results indicated that the sand filter was incapable of effectively removing the saxitoxins and in some instances, the effluent of the sand filter displayed greater toxicity than the influent. Conversely, the sand filter was able to effectively remove geosmin and MIB, with removal attributed to biodegradation. Granular activated carbon was employed as an alternative filter medium to remove the saxitoxins. Results showed similar removals to previous drinking water studies, where efficient removals were initially observed, followed by a decrease in the removal; a consequence of the presence of competing organics which reduced adsorption of the saxitoxins.

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Control of Cryptosporidium with wastewater treatment to prevent its proliferation in the water cycle

Water Science & Technology ◽

10.2166/wst.2003.0488 ◽

2003 ◽

Vol 47 (9) ◽

pp. 45-49 ◽

Cited By ~ 7

Author(s):

M. Suwa ◽

Y. Suzuki

Keyword(s):

Wastewater Treatment ◽

Activated Sludge ◽

Municipal Wastewater ◽

Water Cycle ◽

River System ◽

Chemical Precipitation ◽

Aluminium Chloride ◽

Activated Sludge Process ◽

Sand Filter ◽

Treatment Processes

The outbreak of Cryptosporidiosis in 1996 in Japan is thought to have been enlarged by the proliferation of Cryptosporidium in the water cycle from wastewater to drinking water through the river system. From this experience, the wastewater system must have functions to remove Cryptosporidium oocysts effectively. Efficiencies of wastewater treatment processes to remove oocysts were investigated using pilot plants receiving municipal wastewater. An activated sludge process and a following sand filter showed removal efficiencies of 2 log and 0.5 log, respectively. Poly-aluminium chloride dosage improved the efficiencies by 3 log for the activated sludge process and by 2 log for the sand filter. Chemical precipitation of raw wastewater with poly-aluminium chloride could achieve 1 to 3 log removal according on the coagulant concentration.

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Survey on production quality of electrodialysis reversal and reverse osmosis on municipal wastewater desalination

Water Science & Technology ◽

10.2166/wst.2012.445 ◽

2012 ◽

Vol 66 (10) ◽

pp. 2185-2193 ◽

Cited By ~ 6

Author(s):

Yi-Che Hsu ◽

Hsin-Hsu Huang ◽

Yu-De Huang ◽

Ching-Ping Chu ◽

Yu-Jen Chung ◽

...

Keyword(s):

Wastewater Treatment ◽

Reverse Osmosis ◽

Wastewater Treatment Plant ◽

Municipal Wastewater ◽

Treatment Plant ◽

Municipal Wastewater Treatment ◽

Wastewater Reclamation ◽

Sand Filter ◽

Monovalent Ions

Water shortage has become an emerging environmental issue. Reclamation of the effluent from municipal wastewater treatment plant (WWTP) is feasible for meeting the growth of water requirement from industries. In this study, the results of a pilot-plant setting in Futian wastewater treatment plant (Taichung, Taiwan) were presented. Two processes, sand filter – ultrafiltration – reverse osmosis (SF-UF-RO) and sand filter – electrodialysis reversal (SF-EDR), were operated in parallel to evaluate their stability and filtrate quality. It has been noticed that EDR could accept inflow with worse quality and thus required less pretreatment compared with RO. During the operation, EDR required more frequent chemical cleaning (every 3 weeks) than RO did (every 3 months). For the filtrate quality, the desalination efficiency of SF-EDR ranged from 75 to 80% in continuous operation mode, while the conductivity ranged from 100 to 120 μS/cm, with turbidity at 0.8 NTU and total organic carbon at 1.3 mg/L. SF-EDR was less efficient in desalinating the multivalent ions than SF-UF-RO was. However for the monovalent ions, the performances of the two processes were similar to each other. Noticeably, total trihalomethanes in SF-EDR filtrate was lower than that of SF-UF-RO, probably because the polarization effects formed on the concentrated side of the EDR membrane were not significant. At the end of this study, cost analysis was also conducted to compare the capital requirement of building a full-scale wastewater reclamation plant using the two processes. The results showed that using SF-EDR may cost less than using SF-UF-RO, if the users were to accept the filtrate quality of SF-EDR.

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A small scale hydroponics wastewater treatment system under Swedish conditions

Water Science & Technology ◽

10.2166/wst.2004.0830 ◽

2004 ◽

Vol 48 (11-12) ◽

pp. 161-167 ◽

Cited By ~ 12

Author(s):

A. Norström ◽

K. Larsdotter ◽

L. Gumaelius ◽

J. la Cour Jansen ◽

G. Dalhammar

Keyword(s):

Organic Matter ◽

Wastewater Treatment ◽

Phosphorus Removal ◽

Biological Treatment ◽

Treatment Plant ◽

Domestic Wastewater ◽

Small Scale ◽

Clean Water ◽

Surrounding Area ◽

Sand Filter

A treatment plant using conventional biological treatment combined with hydroponics and microalgae is constructed in a greenhouse in the area of Stockholm, Sweden. The treatment plant is built for research purposes and presently treats 0.559 m3 of domestic wastewater from the surrounding area per day. The system uses anoxic pre-denitrification followed by aerobic tanks for nitrification and plant growth. A microalgal step further reduces phosphorus, and a final sand filter polishes the water. During a three week period in July 2002 the treatment capacity of this system was evaluated with respect to removal of organic matter, phosphorus and nitrogen. 90% COD removal was obtained early in the system. Nitrification and denitrification was well established with total nitrogen reduction of 72%. Phosphorus was removed by 47% in the process. However, higher phosphorus removal values are expected as the microalgal step will be further developed. The results show that acceptable treatment can be achieved using this kind of system. Further optimisation of the system will lead to clean water as well as valuable plants to be harvested from the nutrient rich wastewater.

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Swine Wastewater Treatment Using Submerged Biofilm SBR Process: Enhancement of Performance by Internal Circulation through Sand Filter

Journal of Environmental Engineering ◽

10.1061/(asce)ee.1943-7870.0000199 ◽

2010 ◽

Vol 136 (6) ◽

pp. 585-590

Author(s):

ChangSix Ra ◽

Anthony Lau

Keyword(s):

Wastewater Treatment ◽

Swine Wastewater ◽

Internal Circulation ◽

Sand Filter

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Sequential Application of Plastic Media-Trickling Filter and Sand Filter for Domestic Wastewater Treatment at Low Temperature Condition

British Biotechnology Journal ◽

10.9734/bbj/2012/2013 ◽

2012 ◽

Vol 2 (4) ◽

pp. 179-191 ◽

Cited By ~ 2

Author(s):

Abdul Rehman

Keyword(s):

Wastewater Treatment ◽

Low Temperature ◽

Domestic Wastewater ◽

Trickling Filter ◽

Sand Filter ◽

Domestic Wastewater Treatment ◽

Plastic Media

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Association of septic tank and sand filter for wastewater treatment: full-scale feasibility for decentralized sanitation

Journal of Water Sanitation and Hygiene for Development ◽

10.2166/washdev.2018.094 ◽

2018 ◽

Vol 8 (2) ◽

pp. 268-277 ◽

Cited By ~ 1

Author(s):

Luana Mattos de Oliveira Cruz ◽

Adriano Luiz Tonetti ◽

Bianca Graziella Lento Araujo Gomes

Keyword(s):

Wastewater Treatment ◽

Rural Areas ◽

Precast Concrete ◽

Legal Aspects ◽

Full Scale ◽

Septic Tank ◽

Internal Diameter ◽

Sand Filter ◽

Decentralized System ◽

Operational Conditions

Abstract Worldwide, 70% of the individuals who do not have access to sanitation facilities live in rural areas. A solution for these areas is the use of decentralized systems for wastewater treatment. However, most of the studies about this topic are performed in a laboratory or in pilot scale. This work investigated a full-scale decentralized system. The association of septic tank and sand filter was installed in a rural area in Brazil. Its feasibility, maintenance, and operational conditions were appraised. The septic tank was built with precast concrete rings (inner diameter: 1.90 m; total depth: 2.34 m; useful volume: 4.30 m3). The sand filter was also constructed with precast concrete rings (internal diameter: 1.90 m; surface area: 2.84 m2) and effluent application was intermittent. The hydraulic loading rate of the sand filter was 253 Lm−2day−1. The quality of the effluent met the legal aspects and the system proved to be effective for decentralized sanitation. The final effluent may be reused in agricultural activities; however, the frequency of maintenance of this system should be taken into account.

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Comparison of different advanced disinfection systems for wastewater reclamation

Water Science & Technology Water Supply ◽

10.2166/ws.2002.0105 ◽

2002 ◽

Vol 2 (3) ◽

pp. 213-218 ◽

Cited By ~ 8

Author(s):

M. Salgot ◽

M. Folch ◽

E. Huertas ◽

J. Tapias ◽

D. Avellaneda ◽

...

Keyword(s):

Wastewater Treatment ◽

Chlorine Dioxide ◽

Chemical Treatment ◽

Treatment Plant ◽

The Other ◽

Wastewater Reclamation ◽

Sand Filter ◽

Whole Process ◽

Physico Chemical ◽

Negative Impacts

Several lines of reclamation have been tested in the Palamós/Vall-Llobrega (Girona, Spain) wastewater treatment plant. Each line consists of a filtration treatment (infiltration-percolation, sand filter, ring filter and physico-chemical treatment) plus a disinfection system (UV, peracetic acid, chlorine dioxide and ozonation). Every combination has been evaluated and compared with the other possibilities. This combination of filtration and disinfection allows the use of lower doses of disinfectants, thus minimising the negative impacts of the whole process and improving the reliability of the reclamation facilities.

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