Effect of preformed and non-preformed Al13 species on evolution of floc size, strength and fractal nature of humic acid flocs in coagulation process

2011 ◽  
Vol 78 (1) ◽  
pp. 83-90 ◽  
Author(s):  
Weiying Xu ◽  
Baoyu Gao ◽  
Qinyan Yue ◽  
Qian Wang
Keyword(s):  
Humic Acid ◽  
Fractal Nature ◽  
Floc Size ◽  
Coagulation Process ◽  
Al13 Species

Control of coagulation process by dual wavelength article analyzer

1997 ◽  
Vol 36 (4) ◽  
pp. 135-142 ◽  
Author(s):  
Norihito Tambo ◽  
Yoshihiko Matsui ◽  
Ken-ichi Kurotani ◽  
Masakazu Kubota ◽  
Hirohide Akiyama ◽  
...  
Keyword(s):  
Water Quality ◽  
Control System ◽  
Predictive Control ◽  
Control Method ◽  
Feedforward Control ◽  
Raw Water ◽  
Floc Size ◽  
Coagulation Process ◽  
Series Of Experiments ◽  
Size Data

A coagulation process for water purification plants mainly uses feedforward control based on raw water quality and empirical data and requires operator's help. We developed a new floc sensor for measuring floc size in a flush mixer to be used for floc control. A control system using model predictive control was developed on the floc size data. A series of experiments was performed to confirm controllability of settled water quality by controlling flush mixer floc size. An automatic control with feedback from the coagulation process was evaluated as practical and reliable. Finally this new control method was applied for actual plant and evaluated as practical.

Coagulation of humic acid by ferric chloride in saline (marine) water conditions

2003 ◽  
Vol 47 (1) ◽  
pp. 41-48 ◽  
Author(s):  
J. Duan ◽  
N.J.D. Graham ◽  
F. Wilson
Keyword(s):  
Humic Acid ◽  
Zeta Potential ◽  
Membrane Filtration ◽  
Metal Salt ◽  
Substantial Effect ◽  
Precipitation Process ◽  
Solution Ph ◽  
Floc Size ◽  
Coagulant Dosage ◽  
Co Precipitation

The coagulation of a model seawater-humic acid solution with a hydrolysis metal salt (FeCl3) has been studied by monitoring floc size, solution pH, and zeta potential. The kinetic features of the orthokinetic coagulation have been demonstrated in relation to coagulant dosages, solution pH and zeta potential. Humic acid removal and floc charge reduction increased with coagulant dosage. Adjusting the solution pH prior to coagulation had a substantial effect on the treatment performance. By pH adjustment to pH 6, the greatest humic acid removal (by coagulation and subsequent membrane filtration) and the largest floc size was achieved at a FeCl3 dosage of 200 mmol l−1. It is believed that the coagulation is characterised by competition between OH- ions and humic acid for ferric ions in the co-precipitation process. In acidic pH, where the concentration of OH- ions is low, humic acid molecules may compete more favourably for bonding sites in the co-precipitation, which leads to a more compact precipitation and a higher overall humic acid removal.

Concurrent removal of humic acid and o-dichlorobenzene in drinking water by combined ozonation and bentonite coagulation process

2009 ◽  
Vol 60 (12) ◽  
pp. 3061-3068 ◽  
Author(s):  
Li Gu ◽  
Xingwang zhang ◽  
Lecheng Lei ◽  
Xianjun Liu
Keyword(s):  
Drinking Water ◽  
Humic Acid ◽  
Oxidation Process ◽  
Joint Effect ◽  
Catalytic Ozonation ◽  
Practical Applications ◽  
Coagulation Process ◽  
Wide Range

Combined ozonation and bentonite coagulation process (COBC) was investigated as a method of concurrently removing humic acid (HA) and o-dichlorobenzene (DCB) from drinking water. In this process, HA and DCB were removed by joint effect of catalytic ozonation and bentonite coagulation. HA removal was highly dependent on the coagulation process while DCB removal was dependent on the oxidation process in COBC. Iron in solution not only acted as a coagulant, but also promoted the formation of HO∙, which is effective in destroying aromatic chemicals. Bentonite in COBC improved the coagulation process, resulting in an enhancement in the treating efficiency. COBC is proved to be potentially advantageous on dissolved pollutants in drinking water, and appears to have great potential for a wide range of practical applications.

Oxidation Behavior of Stable-Oxidative-Poly-Si-Fe (SOPSF) Coagulant

2013 ◽  
Vol 341-342 ◽  
pp. 266-269
Author(s):  
Ying Fu ◽  
Yan Zheng Wang ◽  
Juan Tan ◽  
Hong Lan Li ◽  
Xin Yu Zhang
Keyword(s):  
Humic Acid ◽  
Water Glass ◽  
Oxidation Behavior ◽  
Organic Matters ◽  
Whole Process ◽  
Coagulation Process ◽  
Dissolved Organic Matters ◽  
Coagulation Mechanism

The oxidation behavior of a stable-oxidative-poly-Si-Fe (SOPSF) coagulant prepared by water glass and H2SO4 solution in treating a synthetic humic acid (HA) water was probed, in compraison with that of poly-Si-Fe (PSF) and Polyferric aluminum (PFA). The results revealed that the oxidization of SOPSF and PSF was very stable during the whole coagulation process, and played a role during the whole process including quiescent settling stage. While PFA almost gave no oxidization even at higher dose of 0.322 mmol.L-1. The oxidization rate of SOPSF was slower than that of SOPSF hydrolysis and destabilization process. Coagulation mechanism of SOPSF in removing dissolved organic matters (DOMs) may be a comprehensive results between the alternating interaction of oxidization/adsorption-destabilization/oxidization, bridging and sweeping.

Optimization of the Coagulation Process for Kaolin and Humic Acid Removal Using Polymeric Aluminum Ferric Sulfate

2015 ◽  
Vol 1088 ◽  
pp. 353-357 ◽  
Author(s):  
Zhen Zhen Jiang ◽  
Yang Chen ◽  
Jun Ren Zhu
Keyword(s):  
Humic Acid ◽  
Removal Efficiency ◽  
Mixing Time ◽  
Ferric Sulfate ◽  
Single Factor ◽  
Mixing Speed ◽  
Rapid Mixing ◽  
Coagulation Process ◽  
Coagulation Performance ◽  
Slow Mixing

In the paper, the optimization of the coagulation process for Kaolin and humic acid removal using polymeric aluminum ferric sulfate (PAFS) was studied. In order to obtain the maximum turbidity and humic acid removal efficiency of Kaolin and humic acid simulated wastewater, the optimum coagulation conditions was investigated with the factors of mixing speed and time. Furthermore, mixing speed and time including parameters affecting the coagulation performance such as rapid mixing speed, rapid mixing time, slow mixing speed and slow mixing time using single factor and orthogonal array L9 (34) analysis were examined. The results showed that the optimum single factor of mixing speed and time indicated rapid mixing speed of 350 rpm, rapid mixing time of 1.0 min, slow mixing speed of 60 rpm and slow mixing time of 20 min. Then the orthogonal optimization experiment of mixing speed and time indicated maximum HA removal efficiency was 97.5% at rapid mixing speed of 350 rpm, rapid mixing time of 1.25 min, slow mixing speed of 60 rpm, and slow mixing time of 20 min.

scholarly journals Effects of Mixing Conditions on Floc Properties in Magnesium Hydroxide Continuous Coagulation Process

2019 ◽  
Author(s):  
Yanmei Ding ◽  
Jianhai Zhao ◽  
Lei Wei ◽  
Wenpu Li ◽  
Yongzhi Chi
Keyword(s):  
Zeta Potential ◽  
Removal Efficiency ◽  
Magnesium Hydroxide ◽  
Retention Time ◽  
Mixing Conditions ◽  
Floc Size ◽  
Mixing Speed ◽  
Coagulation Process ◽  
Floc Properties ◽  
Reactive Orange

Magnesium hydroxide continuous coagulation process was used for treating simulated reactive orange wastewater in this study. Effects of mixing conditions and retention time on the coagulation performance and floc properties of magnesium hydroxide were based on the floc size distribution (FSD), zeta potential and floc morphology analysis. Floc formation and growth in different reactors were also discussed.The results showed that increasing rapid mixing speed led to a decrease in the final floc size. Floc formation process was mainly carried out in rapid mixer, rapid mixing speed of 300rpm was chosen according to zeta potential and removal efficiency. Reducing retention time caused relatively small floc size in all reactors. When influent flow is 30 L/h (retention time of 2min in rapid mixer), the average floc size reached 8.06μm in rapid mixer, through breakage and re-growth, the floc size remained stable in flocculation basin. After growth, the final floc size reached to 11.21μm in sedimentation tank. The removal efficiency of reactive orange is 89% in magnesium hydroxide coagulation process.

A novel method for on-line evaluation of floc size in coagulation process

2008 ◽  
Vol 42 (10-11) ◽  
pp. 2691-2697 ◽  
Author(s):  
Wen Po Cheng ◽  
Yu Pin Kao ◽  
Ruey Fang Yu
Keyword(s):  
Floc Size ◽  
Coagulation Process ◽  
On Line ◽  
Novel Method

scholarly journals Effect of kaolin on floc properties for reactive orange removal in continuous coagulation process

2018 ◽  
Vol 78 (3) ◽  
pp. 571-577 ◽  
Author(s):  
Jianhai Zhao ◽  
Anmin Wang ◽  
Lei Wei ◽  
Wenqi Ge ◽  
Yongzhi Chi ◽  
...  
Keyword(s):  
Magnesium Hydroxide ◽  
Continuous Process ◽  
Initial Concentration ◽  
Floc Size ◽  
Coagulation Process ◽  
Coagulation Performance ◽  
Process Effects ◽  
Floc Properties ◽  
Reactive Orange ◽  
Floc Breakage

Abstract Magnesium hydroxide was used as a coagulant for treating reactive orange wastewater in a real continuous process. Effects of kaolin on coagulation performance and floc properties were investigated with controlled experiments through floc size distribution, zeta potential, scanning electron microscopy and Fourier transform infrared spectroscopy. Kaolin had significant influence on magnesium hydroxide-reactive orange floc formation and growth. The results showed that average floc size reached 16.31, 12.88 and 20.50 μm, respectively, in the rapid mixer, flocculation basin and sedimentation tank when kaolin concentration was 10 mg/L and reactive orange initial concentration was 0.25 g/L. The floc size tended to increase with the increase of kaolin suspension to 10 mg/L. All of the flocs under investigation showed that floc breakage led to decreased average floc size and remained stable in the flocculation basin. Reactive orange and kaolin could be removed effectively in the continuous coagulation process. Reactive orange was adsorbed in the surface of magnesium hydroxide through charge neutralization and adsorption.

Sign in / Sign up

Export Citation Format

Share Document