Coagulation performance evaluation of sodium alginate used as coagulant aid with aluminum sulfate, iron chloride and titanium tetrachloride

Abstract Coagulation–flocculation was applied to humic acid–kaolin synthetic water samples, using sodium alginate (SA) as a coagulant aid with primary coagulants used: aluminum sulfate (Al2(SO4)3), iron chloride (FeCl3) and titanium tetrachloride (TiCl4). The corresponding dual-coagulants were dented as Al2(SO4)3–SA, FeCl3–SA and TiCl4–SA by dosing SA 30 s after primary coagulants addition. Coagulation performance was investigated in terms of turbidity reduction and dissolved organic carbon (DOC) removal and the flocs were characterized in terms of size, growth rate, strength, recoverability and structure through on‐line monitoring of the coagulation process using Mastersizer 2000. The results showed that dual-coagulants could remove HA effectively with appropriate SA doses. Primary coagulants plus SA exhibited an apparent improvement in both floc growth rate and floc size. Besides, floc recoverability was significantly increased. It was suspected that SA addition may have a positive effect on the solid/liquid separation process. However, dual-coagulants gave the flocs with more open structure.

[1]  R. J. François.  Strength of aluminium hydroxide flocs , 1987 .

[2]  Bruce Jefferson,et al.  Breakage, regrowth, and fractal nature of natural organic matter flocs. , 2005, Environmental science & technology.

[3]  S. Xia,et al.  Production and application of a novel bioflocculant by multiple-microorganism consortia using brewery wastewater as carbon source. , 2007, Journal of environmental sciences.

[4]  R. Wu,et al.  Multilevel structure of sludge flocs. , 2002, Journal of colloid and interface science.

[5]  C. Selomulya,et al.  Evidence of Shear Rate Dependence on Restructuring and Breakup of Latex Aggregates. , 2001, Journal of colloid and interface science.

[6]  S. Martin,et al.  Environmental Applications of Semiconductor Photocatalysis , 1995 .

[7]  Q. Luo,et al.  Characteristics of a bioflocculant produced by Bacillus mucilaginosus and its use in starch wastewater treatment , 2002, Applied Microbiology and Biotechnology.

[8]  N. He,et al.  Production of a novel polygalacturonic acid bioflocculant REA-11 by Corynebacterium glutamicum. , 2004, Bioresource technology.

[9]  Baozhen Li,et al.  Production and characterization of an intracellular bioflocculant by Chryseobacterium daeguense W6 cultured in low nutrition medium. , 2010, Bioresource technology.

[10]  S. Vigneswaran,et al.  Preparation and Characterization of Titanium Dioxide (TiO2) from Sludge produced by TiCl4 Flocculation with FeCl3, Al2(SO4)3 and Ca(OH)2 Coagulant Aids in Wastewater , 2009 .

[11]  R. Hogg,et al.  Agglomerate breakage in polymer-flocculated suspensions , 1987 .

[12]  Huijuan Liu,et al.  Coagulation behavior of aluminum salts in eutrophic water: significance of Al13 species and pH control. , 2006, Environmental science & technology.

[13]  Xiaoying Pan,et al.  Comparative study of the effects of experimental variables on growth rates of aluminum and iron hydroxide flocs during coagulation and their structural characteristics , 2010 .

[14]  C. Mustin,et al.  Evolution of size distribution and transfer of mineral particles between flocs in activated sludges: an insight into floc exchange dynamics. , 2002, Water research.

[15]  A. Campbell.  The potential role of aluminium in Alzheimer's disease. , 2002, Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association.

[16]  B. Gao,et al.  The impact of pH on floc structure characteristic of polyferric chloride in a low DOC and high alkalinity surface water treatment. , 2011, Water research.

[17]  D. Dixon,et al.  Cationic polymer and clay or metal oxide combinations for natural organic matter removal. , 2001, Water research.

[18]  J. Sáez,et al.  Microscopic observation of particle reduction in slaughterhouse wastewater by coagulation-flocculation using ferric sulphate as coagulant and different coagulant aids. , 2003, Water research.

[19]  C. Frochot,et al.  Fate of coagulant species and conformational effects during the aggregation of a model of a humic substance with Al13 polycations. , 2006, Water research.

[20]  B. Jefferson,et al.  The duplicity of floc strength. , 2004, Water science and technology : a journal of the International Association on Water Pollution Research.

[21]  C Rudén,et al.  Acrylamide and cancer risk--expert risk assessments and the public debate. , 2004, Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association.

[22]  W. Cheng.  Comparison of hydrolysis/coagulation behavior of polymeric and monomeric iron coagulants in humic acid solution. , 2002, Chemosphere.

[23]  J. Bonner,et al.  Modeling coagulation kinetics incorporating fractal theories: comparison with observed data. , 2002, Water research.

[24]  Guibai Li,et al.  Breakage and re-growth of flocs formed by alum and PACl , 2009 .

[25]  G. Zeng,et al.  Optimization of flocculation conditions for kaolin suspension using the composite flocculant of MBFGA1 and PAC by response surface methodology. , 2009, Bioresource technology.

[26]  Bing-Jian Wang,et al.  Characterization and coagulation of a polyaluminum chloride (PAC) coagulant with high Al13 content. , 2005, Journal of environmental management.

[27]  S. Zhong,et al.  Production of a novel bioflocculant by Bacillus licheniformis X14 and its application to low temperature drinking water treatment. , 2009, Bioresource technology.

[28]  B. Gao,et al.  Effect of pH on the coagulation performance of Al-based coagulants and residual aluminum speciation during the treatment of humic acid-kaolin synthetic water. , 2010, Journal of hazardous materials.

[29]  H. Shon,et al.  Comparison of coagulation behavior and floc characteristics of titanium tetrachloride (TiCl4) and polyaluminum chloride (PACl) with surface water treatment , 2011 .

[30]  S. Shojaosadati,et al.  Extracellular biopolymeric flocculants. Recent trends and biotechnological importance. , 2001, Biotechnology advances.

[31]  H. Shon,et al.  Coagulation characteristics of titanium (Ti) salt coagulant compared with aluminum (Al) and iron (Fe) salts. , 2011, Journal of hazardous materials.

[32]  N. Titchener-Hooker,et al.  Breakage of flocs in liquid suspensions agitated by vibrating and rotating mixers , 1996 .

[33]  P. Chiang,et al.  Effects of polyelectrolytes on reduction of model compounds via coagulation. , 2005, Chemosphere.

[34]  Yao-de Yan,et al.  Dewatering properties of dual-polymer-flocculated systems , 2004 .

[35]  Dongsheng Wang,et al.  Coagulation of humic acid: The performance of preformed and non-preformed Al species , 2007 .

[36]  R. T. Brown,et al.  TiO2 Photocatalysis for Indoor Air Applications: Effects of Humidity and Trace Contaminant Levels on the Oxidation Rates of Formaldehyde, Toluene, and 1,3-Butadiene. , 1995, Environmental science & technology.

[37]  D. C. Hopkins,et al.  Characterizing flocculation under heterogeneous turbulence. , 2003, Journal of colloid and interface science.

[38]  K. Carlson,et al.  Floc morphology and cyclic shearing recovery: comparison of alum and polyaluminum chloride coagulants. , 2004, Water research.

[39]  R. Schindler,et al.  Influencing the inflammatory response of haemodialysis patients by cytokine elimination using large-pore membranes. , 2002, Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association.

[40]  Paul Lant,et al.  Activated sludge flocculation: on-line determination of floc size and the effect of shear , 2000 .

[41]  B. Gao,et al.  Characterization of floc size, strength and structure in various aluminum coagulants treatment. , 2009, Journal of colloid and interface science.

[42]  H. Stechemesser,et al.  Coagulation and flocculation. , 2005 .

[43]  John Gregory,et al.  The role of floc density in solid-liquid separation☆ , 1998 .

[44]  M. A. Yukselen,et al.  The reversibility of floc breakage , 2004 .

[45]  Stefan Blaser,et al.  Particles under stress , 1998 .

[46]  T. Waite,et al.  Rapid Structure Characterization of Bacterial Aggregates , 1998 .