Removal of bisphenols by slow sand filtration

2009 ◽  
Vol 9 (3) ◽  
pp. 263-268 ◽  
Author(s):  
K. Katayama-Hirayama ◽  
S. Arai ◽  
T. Kobayashi ◽  
H. Matsuda ◽  
Z. Luo ◽  
...  
Keyword(s):  
Removal Rate ◽  
Molecular Orbital Calculation ◽  
Photocatalytic Reaction ◽  
Sand Filtration ◽  
Removal Rates ◽  
Sand Filter ◽  
Slow Sand Filtration ◽  
Initial Concentration ◽  
Slow Sand Filter ◽  
High Removal Rate

A compensating effect in the reduction of bisphenols (BPs) has been shown using biodegradation in slow sand filtration and advanced photocatalysis. We tried to remove 8 kinds of BP by slow sand filtration. Removal rates of BPA, BPB, BPE, BPF, BPS, thiobisphenol (TBP), and dihydroxybenzophenone (DHB) indicated a high removal rate up to more than 90% at an initial concentration of 100 μg/L, whereas the removal rate of BPP was only 30%. We also examined removal of BPs by Pt-loaded porous photocatalyst under visible light irradiation. Removal rates of BPA, BPB, BPE, BPF, BPP, and TBP showed high removal rates up to more than 90% at an initial concentration of 10 mg/L. Removal of BPS and DHB was relatively low at 20% and 30%, respectively. Removal of BPP was low in slow sand filtration, but Pt-loaded photocatalyst removed BPP effectively. Removal of BPS was low with Pt-loaded photocatalyst, but slow sand filtration removed BPS effectively. The combination of a slow sand filter and Pt-loaded photocatalyst may be helpful to degrade BPs. The magnitude of decomposition of BPs by photocatalytic reaction may be related to electrophilic frontier density. But the degradability of BPs in slow sand filtration is not the same as that in photocatalytic reaction with Pt-loaded titanium dioxide. The biodegradability of BPs by slow sand filtration cannot be explained by molecular orbital calculation.

Enhanced removal of herbicides by different in-site barrier-systems (GAC, FAC, anthracite, lignite coke) in slow sand filtration

2002 ◽  
Vol 2 (1) ◽  
pp. 123-128
Author(s):  
C. Donner ◽  
F. Remmler ◽  
N. Zullei-Seibert ◽  
U. Schöttler ◽  
P. Grathwohl
Keyword(s):  
Activated Carbons ◽  
Ph Value ◽  
Operation Time ◽  
Sand Filtration ◽  
Artificial Groundwater Recharge ◽  
Sand Filter ◽  
Slow Sand Filtration ◽  
Pesticide Removal ◽  
Slow Sand Filter ◽  
Filter Operation

Improvement of artificial groundwater recharge via slow sand filtration combined with different in-site barrier-layers (activated carbons, anthracite, lignite coke) was tested. The micropollutant control of the systems achieve significant different pesticides reductions. Operation time depends on the micropore structure and site properties of the activated carbons (Sorption reactor) and reaches a calculated slow sand filter operation time of nearly 6 years (GAC). No distinct improvement of pesticide removal was observed by anthracite (biological reactor). Lignite coke was not used in pilot plant, because of its high pH-value during first 100 bed volumes.

Elimination of terpenoid odorous compounds by slow sand and river bank filtration of the Ruhr River, Germany

1995 ◽  
Vol 31 (11) ◽  
pp. 211-217 ◽  
Author(s):  
F. Jüttner
Keyword(s):  
Bank Filtration ◽  
Sand Filtration ◽  
Sand Filters ◽  
Slow Sand Filtration ◽  
River Bank ◽  
Lipophilic Compounds ◽  
Slow Sand Filter ◽  
Odorous Compounds ◽  
Aliphatic And Aromatic Hydrocarbons ◽  
River Bank Filtration

The elimination of odorous compounds by river bank and slow sand filtration was studied at the Ruhr River in Germany. The aquifer of the river bank filtration was anoxic and exhibited intense dissimilatory nitrate reduction; the aquifer of the slow sand filter was oxic. Polar monoterpenes, such as linalool, menthol, isobornyl acetate, lipoxygenase products (oct-1-en-3-ol) and geosmin exhibited a much higher percentage elimination than monoterpene hydrocarbons and other lipophilic compounds (dimethyldisulphide, aliphatic and aromatic hydrocarbons). The efficiency of river bank filtration was slightly better than that of slow sand filtration. The schmutzdecke and upper layers of the slow sand filters were responsible for most of the removal of VOC. The deeper layers exhibited only small effects.

Removal of Uranium From Aqueous Solution by Chitosan and Ferrous Ions

2010 ◽  
Author(s):  
Jing-song Wang ◽  
Zheng-lei Bao ◽  
Si-guang Chen ◽  
Jin-hui Yang
Keyword(s):  
Aqueous Solution ◽  
Removal Rate ◽  
Synergetic Effect ◽  
Ferrous Ions ◽  
Experimental Conditions ◽  
Initial Concentration ◽  
Batch Systems ◽  
Uranium Ions ◽  
High Removal Rate ◽  
The Given

This study focuses on developing a new method to remove uranium from aqueous solution. Chitosan and ferrous ions were used together to remove uranium ions from aqueous solution. Through two-step pH adjustment, the uptake behavior of chitosan and ferrous ions toward uranium in aqueous solution using batch systems were studied in different experimental conditions. The experimental results indicated that the removal of uranium by synergetic effect of chitosan and ferrous ions was more effective than the way of adsorbing uranium ions by chitosan alone. Under the given experimental conditions, the concentration of the residual uranium in the effluent after chitosan and ferrous ions treatment could meet the discharge standard (< 0.05mg·l−1) when initial concentration of uranium ions was 10 mg·l−1 or 100 mg·l−1. The synergetic effect of chitosan and ferrous ions including adsorption, coacervation and coprecipitation, are responsible for the high removal rate of uranium.

Chemically enhanced gravel pre-filtration for slow sand filters: advantages and pitfalls

2006 ◽  
Vol 6 (1) ◽  
pp. 121-128
Author(s):  
C.C. Dorea ◽  
B.A. Clarke
Keyword(s):  
Negative Impact ◽  
Pilot Scale ◽  
Sand Filtration ◽  
Sand Filters ◽  
Slow Sand Filtration ◽  
Chemical Enhancement ◽  
Dissolved Organics ◽  
Efficiency And Effectiveness ◽  
Slow Sand Filter ◽  
Pre Treatment

The chemical enhancement of gravel (or roughing) filtration with coagulants, i.e. direct (gravel) filtration, has been proposed as a pre-treatment alternative for slow sand filters. However, studies have frequently focused on the efficiencies of the pre-filters in terms of reduction percentages. The effectiveness of the pre-treatment on the subsequent slow sand filtration is not usually cited or even evaluated. By incorporating a pilot-scale slow sand filter in our trials, both aspects of the pre-treatment process were assessed: efficiency and effectiveness. In terms of turbidity reductions, our results demonstrated that chemically enhanced pre-filtration was substantially more efficient (93.2 to 99.5%) than conventional pre-filtration (50.6 to 79.3); this was also observed in terms of reductions in the level of other parameters (i.e. thermotolerant faecal coliforms and dissolved organics). Yet, the use of a coagulant can have a negative impact on the slow sand filtration run.

Removal of cyanobacteria by slow sand filtration for drinking water

2012 ◽  
Vol 2 (3) ◽  
pp. 133-145 ◽  
Author(s):  
Silvano Porto Pereira ◽  
Fabiana de Cerqueira Martins ◽  
Lenora Nunes Ludolf Gomes ◽  
Manoel do Vale Sales ◽  
Valter Lúcio De Pádua
Keyword(s):  
Water Treatment ◽  
Rural Communities ◽  
Human Consumption ◽  
Industrialized Countries ◽  
Sand Filtration ◽  
Intact Cells ◽  
Slow Sand Filtration ◽  
Treatment Techniques ◽  
Slow Sand Filter ◽  
The City

Potential problems arising from the presence of cyanobacteria in water intended for human consumption have been reported by several researchers. Regarding water treatment plants, intact cells of cyanobacteria should be removed to avoid the release of cyanotoxins due to cell lysis. Water treatment techniques with different degrees of complexity can be employed but, whenever possible, the method of easiest installation, operation and maintenance should be selected, especially for non-industrialized countries and rural communities. In this context, research was carried out to evaluate the efficiency of slow sand filtration to treat water from Gavião reservoir in the city of Pacatuba, Ceara, Brazil, which has exhibited phytoplankton density of approximately 105 cells/mL with a prevalence of cyanobacteria representing over 90% of total cells. The results have demonstrated that slow sand filtration can be used to achieve water purification that meets federal standards. However, it was established that filtration through beds of gravel (prefilter) before the slow sand filtration is essential. The removal of phytoplankton reached values of approximately 97% and the filter run duration was more than 70 days. Furthermore, the slow sand filter was very efficient in removing total coliforms, with removal of up to 99.98%.

Virus Removal by Slow Sand Filtration and Nanofiltration

1993 ◽  
Vol 27 (3-4) ◽  
pp. 445-448 ◽  
Author(s):  
M. T. Yahya ◽  
C. B. Cluff ◽  
C. P. Gerba
Keyword(s):  
Surface Water ◽  
Pilot Plant ◽  
The United States ◽  
Sand Filtration ◽  
Treatment Technology ◽  
Sand Filter ◽  
Slow Sand Filtration ◽  
Virus Removal ◽  
Reject Water ◽  
Log Reduction

Water utilities, especially smaller ones, are having increasing difficulties proving increased treatment requirements required in the United States for the removal of chemical and microbial contaminates in drinking water. This project sought to evaluate the virus removal potential of combined slow sand filtration and nanofiltration by a pilot plant for application to a small utility which uses a surface water supply. Nanofiltration is a relatively new water treatment technology which has become available since 1986. It is similar to reverse osmosis but has a higher molecular weight cut-off and is less costly to operate. The bacteriophages MS-2 (28 nm) and PRD-1 (65 nm) were seeded into surface water entering a pilot plant and samples collected after sand filtration, nanofiltration, and of the nanofilter reject water. These phages were selected for study because of their small size and poor adsorption to surfaces. The slow sand filter removed 99% of the MS-2 and 99.9% of the PRD-1. There was between a 4 to 6 log reduction of the phages by the nanofilters. PRD-1 was removed to a greater extent than MS-2 by both the sand filter and the nanofilters.

A Study on Water Hyacinth Purifying Effect on Different Levels of Eutrophic Water

2014 ◽  
Vol 955-959 ◽  
pp. 1899-1902
Author(s):  
Su Chen ◽  
Lei Chao ◽  
Ning Chen ◽  
Lin Shan Wang ◽  
Xin Liu ◽  
...  
Keyword(s):  
Total Nitrogen ◽  
Total Phosphorus ◽  
Water Hyacinth ◽  
Removal Rate ◽  
Dry Weight ◽  
Total Biomass ◽  
Removal Rates ◽  
Initial Concentration ◽  
Eutrophic Water ◽  
Different Levels

In this experiment, water hyacinth presents a good purification effect in five kinds of eutrophic waters with initial total nitrogen (TN) and total phosphorus (TP) concentrations in between 8.34~20.45 mg/L and 0.78~1.51 mg/L. After two weeks of purification, TN and TP concentrations of eutrophic waters are reduced to 1.78~5.68 mg/L and 0.25~0.312 mg/L, and TN and TP removal rates are 72.22~78.65% and 67.95~79.34%. Water hyacinth’s TN removal rate decreases as TN initial concentration increases; TP removal rate increases as TP initial concentration increases. Water hyacinth’s average total biomass in eutrophic water has increased by 0.944~1.084 kg/m2, and the average bio-dry-weight has increased by 0.0470~0.0547 kg/m2. The average total biomass and average bio-dry-weight of water hyacinth increase as the eutrophication deepens.

Photocatalysis and Biodegradation Coupled Intimately for Treatment of the Black-Odor Water

2021 ◽  
Vol 15 (1) ◽  
pp. 61-68
Author(s):  
Jianhua Xiong ◽  
Chunlin Jiao ◽  
Liushu Pan ◽  
Jue Wang ◽  
Hao Cheng ◽  
...  
Keyword(s):  
Water Pollution ◽  
High Efficiency ◽  
Removal Rate ◽  
Quality Standard ◽  
Class Iii ◽  
Optimum Conditions ◽  
Key Factors ◽  
Removal Rates ◽  
High Removal Rate ◽  
Maximum Removal

Black-odor water remains an important problem of water pollution control in China. An increasing number of studies have thus investigated combined technologies for water pollution. Among them, many researchers prefer the intimate coupling of photocatalysis and biodegradation (ICPB) for its characteristics of high efficiency and high removal rate for refractory organics. In this study, porous cellulose-TiO2, which has advantages of good responsiveness, stability, and friendliness towards microorganisms, was introduced into the ICPB system as a crucial carrier for cleaning black-odor water. The key factors of this system were changed to obtain the optimum conditions (carrier mass 4 g, pH 7, and light intensity 25 W), and three comparison protocols including UV-responsive photocatalysis (UPC), biodegradation (B), and the coupled (PB) were carried out. The results showed removal rates of 59.06% (UPC), 68.20% (B), and 92.06% (PB) for COD, 59.96% (UPC), 82.36% (B), and 97.16% (PB) for NH3–N, and 69.00% (UPC), 85.61% (B), and 94.83% (PB) for TP. Obviously, the coupled treatment exhibited the maximum removal rates for the three indexes. Moreover, with the coupled treatment, the effluent water quality could meet the requirement of Class III water of the Environmental Quality Standard for Surface Water (GB3838-2002).

Inconsiderable Amount of Phytoplankton Leakage by Algal Mat Peeling from a Slow Sand Filter.

1997 ◽  
Vol 33 (4) ◽  
pp. 179-186 ◽  
Author(s):  
NOBUTADA NAKAMOTO ◽  
NORIYASU IWASE ◽  
KENTARO NOZAKI ◽  
MASASHI SAKAI
Keyword(s):  
Sand Filter ◽  
Slow Sand Filter ◽  
Algal Mat

Analysis of organic removal rates in the aerated submerged fixed film process

1998 ◽  
Vol 38 (8-9) ◽  
pp. 213-221 ◽  
Author(s):  
Mohamed F. Hamoda ◽  
Ibrahim A. Al-Ghusain
Keyword(s):  
Pilot Plant ◽  
Removal Rate ◽  
Domestic Wastewater ◽  
Removal Rates ◽  
Hydraulic Loading ◽  
Organic Removal ◽  
Wide Range ◽  
Fixed Film ◽  
Cod Removal Rate ◽  
And Performance

Performance data from a pilot-plant employing the four-stage aerated submerged fixed film (ASFF) process treating domestic wastewater were analyzed to examine the organic removal rates. The process has shown high BOD removal efficiencies (&gt; 90%) over a wide range of hydraulic loading rates (0.04 to 0.68 m3/m2·d). It could also cope with high hydraulic and organic loadings with minimal loss in efficiency due to the large amount of immobilized biomass attained. The organic (BOD and COD) removal rate was influenced by the hydraulic loadings applied, but organic removal rates of up to 104 kg BOD/ m2·d were obtained at a hydraulic loading rate of 0.68 m3/m2·d. A Semi-empirical model for the bio-oxidation of organics in the ASFF process has been formulated and rate constants were calculated based on statistical analysis of pilot-plant data. The relationships obtained are very useful for analyzing the design and performance of the ASFF process and a variety of attached growth processes.

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