Comparison of different advanced disinfection systems for wastewater reclamation

2002 ◽  
Vol 2 (3) ◽  
pp. 213-218 ◽  
Author(s):  
M. Salgot ◽  
M. Folch ◽  
E. Huertas ◽  
J. Tapias ◽  
D. Avellaneda ◽  
...  

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.

2013 ◽  
Vol 9 (2) ◽  
pp. 166-173

The present study investigated tertiary physico-chemical treatment of the secondary effluent from the Chania municipal Wastewater Treatment Plant (WTP). Laboratory experiments were carried out with the aim of studying coagulation efficiency regarding reduction of turbidity, soluble COD and phosphorus both in a conventional Coagulation-Settling treatment scheme, as well as by means of Contact Filtration. The results showed that high doses of coagulants (0,5 mmol Me+3 l-1 or higher) are required to achieve significant removals of turbidity after settling. At these high doses, soluble COD can be removed by about 50%, while soluble Phosphorus by 80-95%. Ferric Chloride demonstrated slightly better removal ability as compared to Alum. The Chania WTP effluent was also treated by Contact Filtration, using a very low dose of coagulants, 0,1 mmol Me+3 l-1. Turbidity was removed by around 50%, while at this low coagulant dose removals of COD and Phosphorus were insignificant. Filtration was effective in the first 35cm of the filter bed. No significant differences were observed between the coagulants Alum and FeCl3 in the elimination of turbidity. Nevertheless, with the use of Alum a smaller filter headloss was observed, during the first two hours of continuous filtration, in comparison with the use of FeCl3 (nearly double). No difference was observed between the headloss developed at a filter depth of 5cm as compared to that developed at a depth of 70cm. This indicates that the headloss increase was due to the accumulation of suspended and colloidal solids within the first layers of the sand filter.


2012 ◽  
Vol 66 (10) ◽  
pp. 2185-2193 ◽  
Author(s):  
Yi-Che Hsu ◽  
Hsin-Hsu Huang ◽  
Yu-De Huang ◽  
Ching-Ping Chu ◽  
Yu-Jen Chung ◽  
...  

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.


2003 ◽  
Vol 3 (3) ◽  
pp. 161-165
Author(s):  
M. Folch ◽  
E. Huertas ◽  
J.C. Tapias ◽  
M. Salgot ◽  
F. Brissaud

The DRAC, (“Desinfecció i Reutilització d'Agües Residuals a Catalunya”, Wastewater disinfection and reuse in Catalonia - Spain), project is included in a RDD (Research, Development, and Demonstration) program. The project arises from the necessity to define reclamation treatments guaranteeing an effluent with enough quality to be reused with a minimal microbiological risk. This paper presents the first results obtained from the combination of a physical-chemical pilot and two disinfection pilot systems: ozone and chlorine dioxide. The combination of physical-chemical and disinfection systems 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.


2006 ◽  
Vol 54 (10) ◽  
pp. 39-45
Author(s):  
A. Vargas ◽  
D. González ◽  
A. Estival ◽  
G. Buitrón

This work presents a comparison of two inocula used for the acclimation of two anaerobic-aerobic sequencing batch bioreactors used for toxic wastewater treatment. The bioreactors were acclimated with different types of sludge: one coming from an anaerobic wastewater treatment plant and the other one from a conventional aerobic activated sludge plant. The model toxic compound was p-nitrophenol, which is reduced to p-aminophenol during the initial anaerobic phase of the reaction, and later mineralized during a posterior aerated reaction phase. Biodegradation of the compounds was monitored using UV/Vis spectrophotometry. After acclimation stabilization of the sludge and of the process was also monitored. Results show that there is no significant difference in acclimation times and stability of the process between the two employed inocula, and thus an originally anaerobic inoculum presents no apparent advantage over a more easily accessible aerobic one.


2013 ◽  
Vol 777 ◽  
pp. 192-195
Author(s):  
Lan Wu ◽  
Wen Liang Gao ◽  
Bao Yu Liu

A new biological deodorization technology which is used in Tianjin Jizhuangzi Sewage Plant was introduced in this paper. The geographical position of Jizhuangzi Wastewater Treatment Plant is special. The plant has been surrounded by the living area. The problem of odor to people has been serious until a new deodorization technology is used. It is a source deodorization technology used special filler through vaccination, induction and catalytic to removed the malodorous sources. A special microbial incubator is used to culture and proliferate effective deodorant microorganisms on activated sludge sewage in the biological pool of the plant and then the sludge containing deodorant microbial reflowed to the wastewater inlet. The malodorous substances in the water are removed through adsorption, cohesion, biotransformation degradation and so on by the deodorant microbial. The case indicates that this technology is effective in practice and good for popularization. And this technology with simple process showed significant effect compared with other deodorant technologies and was more secure and convenient to build and run with low cost.


1972 ◽  
Vol 7 (1) ◽  
pp. 1-12
Author(s):  
A. Benedek

Abstract Recent developments in the application of activated carbon to wastewater treatment are reviewed. Particular emphasis is placed on the physico-chemical treatment of municipal waste. Technological development, adsorptive behaviour, and research needs serve as the three primary discussion topics.


2001 ◽  
Vol 44 (1) ◽  
pp. 33-39 ◽  
Author(s):  
O. Tornes

Norway is a leading country on wastewater treatment comprising chemical precipitation processes. This is because Norwegian effluent standards to the North Sea have traditionally focused on phosphorus removal. In most cases, chemical treatment therefore has been considered to give lower investment and operating costs than biological treatment. Norwegian wastewater policy and management is based on the EU guidelines resulting from the EEA (European Economic Area) Agreement. According to the 1991 Urban Wastewater Treatment Directive, this will in most cases require secondary treatment. However, primary treatment can be accepted for plants larger than 10,000 PT with effluents to less sensitive coastal areas, if no negative environmental impacts can be proved. The main objective of the Regional Water, Sewerage and Waste Company (IVAR) is to comply with the prevailing effluent limits at lowest possible cost. During the past four years, IVAR has therefore undertaken comprehensive optimising of the precipitation process including full-scale experiments with different coagulant dosing control systems and different types of coagulants. IVAR also accomplished a feasibility study of introducing biological treatment as an alternative to chemical treatment. Under the prevailing frame conditions of discharge requirements and sludge deposit costs, it is not economically feasible to change to organic coagulants or biological treatment. This conclusion might have to be altered later resulting from the implementation of new EU regulations and increasing sludge deposit costs. This paper presents results from full-scale experiments, extracts from the feasibility study and a comparison of costs. Furthermore, the practical consequences of implementing the EU-guidelines are discussed.


2002 ◽  
Vol 46 (6-7) ◽  
pp. 297-302 ◽  
Author(s):  
Z. Tonkovic ◽  
S. Jeffcoat

The Mt Buller Alpine Resort is located approximately 200 km north of Melbourne, in Victoria, Australia. A wastewater treatment plant services the resort and currently treats to advanced nutrient removal standards. The treated effluent is presently discharged into the Howqua River. Most Australian ski resorts are not blessed with abundant snow cover on a regular basis. Artificial snow allows most of the popular ski runs to operate for the whole of the season. At the Mt Buller resort, snow-making is presently limited by lack of water supply in the catchment. The conditions at Mt Buller resort present a unique opportunity to utilise reclaimed wastewater to allow increased snow-making capacity. It is one of the unique opportunities where the wastewater is valued as a resource rather than merely viewed as a waste problem. Wastewater reclamation for snow-making will require additional treatment for pathogen removal. It is proposed that following advanced nutrient removal, the effluent will require further treatment, including membrane ultrafiltration, so as to ensure a minimum of four barriers for pathogen removal. Pilot plant operation of a membrane ultrafiltration system commenced in June 2000 and will continue until the end of 2001, to primarily demonstrate the extent of pathogen removal.


2012 ◽  
Vol 65 (7) ◽  
pp. 1244-1251 ◽  
Author(s):  
Lionel Ho ◽  
Daniel Hoefel ◽  
Charlotte Grasset ◽  
Sebastien Palazot ◽  
Gayle Newcombe ◽  
...  

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.


2020 ◽  
Vol 1 (4) ◽  
pp. 9-15
Author(s):  
Rafael Marín Galvín

Bio-solids are the final fate of pollution present in urban wastewater, reaching the production of these ones in Spanish WWTPs 701,751 T/year (dates of 2018). Considering that 85% of Spanish bio-solids are used in agronomy, it is important to know characteristics of biosolids there produced, and in this way, we have investigated bio-solids generated in La Golondrina´s WWTP (Córdoba, Spain) along 2000-2019. This WWTP is a conventional facility operated by activated sludges (26.55x106 m3/year treated) which has produced 1.43 kg of bio-solids per m3 of treated wastewater (38.000 T/year). Our results indicated that bio-solids had a dryness over initial mass of 22.3%, and 74.9% of organic matter over dried matter (o.d.m.). At the same time, major components detected in bio-solids were N, P and Ca which levels were 5.0%, 3.5% and 3.7%, respectively. On the other hand, concentration of total metals in bio-solids ranged 13,024 mg/kg o.d.m., being the main metal Fe (11.749 mg/kg o.d.m.) followed by Zn, Cu and Mn, with levels as mg/kg o.d.m. of 463.1, 392.8 and 265.7, respectively. Evolution per year of all the investigated parameters are shown in the paper. Taking into account the use of bio-solids in agronomy, we have evaluated levels of metals limited by the Spanish normative to this respect: thus, the seven metals restricted (Cd, Cu, Ni, Pb, Zn, Hg and Cr) exhibited concentration in bio-solids very lower than parametric values established. Moreover, we have estimated the ratios of accumulation of organics and metals from wastewater to bio-solids: thus, organic matter, N and P, were accumulated in bio-solids respectively, 342, 356 and 643 times, and total metals, 2,632 times. Finally, levels of Escherichia coli slightly varied from wastewater to bio-solids: 1.5x108 colony-forming units/L in the first one, and 0.9x108/g (o.d.m.) in the second ones.


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