Removal of THM precursors from a high-alkaline surface water by enhanced coagulation and behaviour of THMFP toxicity on D. magna

Rizzo, Luigi; Belgıorno, Vincenzo; Gallo, M.; Meriç, Süreyya

doi:10.1016/j.desal.2004.10.020

Cited by 44 publications

(35 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Some researchers found that PACl was able to directly precipitate fulvic acids (FA) over a broad pH range and could be a better coagulant than alum at more acidic and basic pH values [3,12]. While some investigators observed that PACl did not reduce DOM as effectively as alum [13,14].…”

Section: Introductionmentioning

confidence: 99%

“…PACl is less sensitive to changes in pH and temperature [8][9][10]. In addition, the high positive charge of some polycations, such as Al 13 [AlO 4 Al 12 (OH) 24 (H 2 O) 12 7+ ], is highly effective in neutralizing the negative charges of colloidal particles [11].…”

Section: Introductionmentioning

confidence: 99%

“…1. The signal at 0 ppm corresponds to monomeric species and the signal at 62.5 ppm corresponds to Al 13 species (only the central Al atom in Al 13 structure can produce resonance signal), the signal at 80 ppm is ascribed to the inner standard of NaAl(OD) 4 . Other Al species, such as colloidal species cannot be observed by 27 Al NMR.…”

Section: Coagulants Preparation and Characterizationmentioning

confidence: 99%

“…The temperature was kept at 70 • C by using recycling water bath. The target basicity (OH/Al molar ratio) of the PACl was 2.20; (3) Al 13 : it was separated and purified from PACl using sulfate precipitation and nitrate metathesis reactions. The detailed procedures can be found in [16].…”

Section: Coagulants Preparation and Characterizationmentioning

confidence: 99%

See 3 more Smart Citations

Coagulation of humic acid: The performance of preformed and non-preformed Al species

Shi

Wei

Wang

et al. 2007

Colloids and Surfaces A: Physicochemical and Engineering Aspect

View full text Add to dashboard Cite

Inorganic polymeric Al coagulants have been being widely used in water treatment due to their advantages of applicability within broad pH and temperature ranges, high capacity of charge neutralization as well as less alkalinity consumption. However, the removal of dissolved organic matter (DOM) by such kind of coagulants has not been well understood because of the complexity of natural organic matter and the diversity of such polymeric Al coagulants. In this paper, coagulants with different Al speciation characteristics were prepared to conduct coagulation of humic acid (HA). The humic acid used was peat origin and was characterized physicochemically. The results showed that coagulants with preformed Al species were less effective than conventional Al salt in removing humic acid with large molecular and hydrophobic properties. The flocs formed by preformed Al species were smaller than those formed by conventional Al salt. Decreasing pH could improve the coagulation performance of all coagulants. Coagulation of humic acid might not follow the same charge neutralization rules associated with coagulation of mineral colloids. In the presence of humic acid, Al 13 could be decomposed during coagulation process.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Coagulants Preparation and Characterizationmentioning

confidence: 99%

Section: Coagulants Preparation and Characterizationmentioning

confidence: 99%

See 2 more Smart Citations

Coagulation of humic acid: The performance of preformed and non-preformed Al species

Shi

Wei

Wang

et al. 2007

Colloids and Surfaces A: Physicochemical and Engineering Aspect

View full text Add to dashboard Cite

show abstract

“…The process is based on the use of Al(III) or Fe(III) salts alone or in combination with calcium salts and the use of polymers as flocculants. Coagulant doses vary in a wide range like 150-600 mg/L and 250-2000 mg/L of Al 2 (SO 4 ) 3 (alum) used for treatment of domestic [Meriç et al, 2002a,b;Delgado et al, 2003] and industrial wastewaters [Rossini et al,1999;Selçuk et al, 2004], respectively while 20-60 mg/L of alum was applied as the proper interval for drinking water production [Volk et al, 2000;Rizzo et al, 2005]. In addition to aluminium sulfate, alternative coagulants, such as ferric chloride [Delgado et al, 2003], NH 4 -ferric chloride [Gao et al, 2002a[Gao et al, -b,2003] can used trying to improve coagulation efficiency as well as associated with ascorbic acid in the water.…”

Section: Introductionmentioning

confidence: 99%

Ascorbic Acid as an Auxiliary to Enhance Coagulation for Turbidity and Total Solids Removal From Greywater

Revolta¹,

Franco²

2015

Anais Do XX Congresso Brasileiro De Engenharia Química

View full text Add to dashboard Cite

-Alum-coagulation, Iron-coagulation and Iron-NH 4 enhanced with ascorbic acid were used on the samples that were synthetically prepared and treated in reactors at ambient temperature to meet the Brazilian water quality discharge limits or to be reused. A series of jar test experiments was run at 150 rpm for 2 min and 30 min for settling. 95 mg/L dose of traditional coagulant (alum, iron or iron-NH 4 ) was applied at pH ranging from 4-10. The coagulation was enhanced by adding doses of ascorbic acid resulting in three concentrations: 2.38, 7.14 and 11.9 g/L. Raw and coagulated greywater samples were analyzed for their turbidity, TS and conductivity as a function of time. The jar test experiments provided evidence that coagulation process could not provide sufficient TS removal efficiency in the greywater except at an iron-NH 4 + acid in all concentrations of the acid reaching a maximum removal after 4-5 h decanting. Turbidity was better removed when the small concentrations of ascorbic acid was employed. Generally, enhanced coagulation process using ascorbic acid was not sufficient to meet turbidity (< 20 mg/L) and TS (100 mg/L) limits. The highest turbidity removal (95%) was obtained at the range of 2.0-4.3 pH values, whereas turbidity removal was lesser in the greywater treated with Iron Chloride in the 11.90 g/L concentration. All experiments with controlled pH resulted in treated greywater with increasing in conductivity. Conductivity was found significantly high when controlled pH was used in the coagulation process.

show abstract

Reduction of dissolved organic matter in secondary municipal effluents by enhanced coagulation

Xue

Zhao

Wei

et al. 2014

Env Prog and Sustain Energy

View full text Add to dashboard Cite

Jar test experiments were performed to investigate the reductions of dissolved organic matter (DOM) in secondary municipal effluents by coagulation, as well as the effect of coagulation on the structural and functional properties of DOM fractions. The reductions of 9-58% and 17-71% in dissolved organic carbon (DOC) and the removals of 30-75% and 30-83% in absorbance of ultraviolet light at 254 nm (UV-254) were obtained by coagulation of two secondary municipal effluents, respectively. Moreover, the order of DOC and UV-254 removals by coagulation was pH 5 > pH 6 > unadjusted pH at all coagulant dosages. The reductions of the bulk fluorescent materials by coagulation were lower than those of UV-254 absorbing compounds. Among four types of fluorophores, aromatic protein-like fluorophores were preferentially removed by coagulation. The coagulation treatability of hydrophobic acid (HPO-A) was the highest and that of hydrophilic fraction (HPI) was the lowest, among five DOM fractions. In addition, the value of specific ultraviolet light absorbance for each DOM fraction decreased significantly after coagulation. The Fourier-transform infrared spectra revealed that aromatics were effectively removed by coagulation while coagulation seemed to be inefficient in removing amide-2 functional groups and those hydrocarbons exhibiting absorbance characters at 2950-2850 cm 21 .

show abstract

Removal of THM precursors from a high-alkaline surface water by enhanced coagulation and behaviour of THMFP toxicity on D. magna

Cited by 44 publications

References 22 publications

Coagulation of humic acid: The performance of preformed and non-preformed Al species

Coagulation of humic acid: The performance of preformed and non-preformed Al species

Ascorbic Acid as an Auxiliary to Enhance Coagulation for Turbidity and Total Solids Removal From Greywater

Reduction of dissolved organic matter in secondary municipal effluents by enhanced coagulation

Contact Info

Product

Resources

About