Optimisation of orthophosphate and turbidity removal using an amphoteric chitosan-based flocculant–ferric chloride coagulant system

2019 ◽  
Vol 16 (8) ◽  
pp. 599 ◽  
Author(s):  
Henry K. Agbovi ◽  
Lee D. Wilson
Keyword(s):  
Ferric Chloride ◽  
Aqueous Media ◽  
Test System ◽  
Settling Time ◽  
Interactive Effects ◽  
Trimethylammonium Chloride ◽  
Water And Wastewater Treatment ◽  
Turbidity Removal ◽  
Covalent Grafting ◽  
Flocculation Process

Environmental contextThe fate and build-up of phosphate nutrients in aquatic environments is an urgent environmental problem affecting global water security. This study, guided by a statistical design method, optimises the flocculation properties of a biopolymer for removing orthophosphate from water. This improved technology has potential widespread applications for removal of orthophosphate from water and wastewater treatment systems. AbstractA coagulation-flocculation process was employed to remove turbidity (Ti) and orthophosphate (Pi) in aqueous media using a ferric chloride (FeCl3) and a grafted carboxymethyl chitosan (CMC) flocculant system. The amphoteric CMC-CTA flocculant was synthesised by grafting 3-chloro-2-hydroxypropyl trimethylammonium chloride (CTA) onto the biopolymer backbone of CMC. Here, CMC-CTA denotes the covalent grafting of CTA onto CMC. Optimisation of the variables for Pi and Ti removal was conducted using a jar test system based on the experimental design obtained from the response surface methodology (RSM). The Box–Behnken design was used to evaluate the individual and interactive effects of four independent variables: CMC-CTA dosage, FeCl3 dosage, pH and settling time. The RSM analysis showed that the experimental data followed a quadratic polynomial model with the following optimal conditions: [CMC-CTA]=3.0mgL−1, [FeCl3]=10.0mgL−1, pH 6.8 and settling time=35min. Optimum conditions led to a Pi removal of 96.4% and turbidity removal of 96.7% based on the RSM optimisation, in good agreement with experimental results with an initial concentration of 30.0mg PiL−1. The coagulation-flocculation process is characterised by a combination of electrostatic charge neutralisation, polymer bridging and a polymer adsorption mechanism.

Treatment of Textile Wastewater using Biodegradable Flocculants of Chitosan and Extracted Pandan Leaves

2013 ◽  
Vol 64 (1) ◽  
Author(s):  
Norzita Ngadi ◽  
Nor Aida Yusoff
Keyword(s):  
Solvent Extraction ◽  
Extraction Method ◽  
Textile Wastewater ◽  
Settling Time ◽  
Turbidity Removal ◽  
Test Experiment ◽  
Jar Test ◽  
Solvent Extraction Method ◽  
Flocculation Process

The study investigated the performance of chitosan and extracted pandan leaves towards treatment of textile wastewater by using flocculation process. Pandan leaves were extracted by using solvent extraction method. Flocculation process was conducted using a Jar test experiment. The effect of dosage, pH, and settling time on reduction of COD, turbidity and color of textile wastewater was studied. The results obtained found that chitosan was very effective for reduction of COD, turbidity, color and indicator for color. The best condition for COD and turbidity removal was achieved at 0.2 g dosage, pH 4 and 60 minutes of settling time. Under this condition, about 58 and 99% of COD and turbidity was removed, respectively. However, the results obtained using extracted pandan was opposite compared to the chitosan. Extracted pandan was not able to remove both COD and turbidity of the waste. 

Evaluation of polyaluminium ferric chloride (PAFC) as a composite coagulant for water and wastewater treatment

2003 ◽  
Vol 47 (1) ◽  
pp. 127-132 ◽  
Author(s):  
B. Gao ◽  
Q. Yue ◽  
J. Miao
Keyword(s):  
Zeta Potential ◽  
Ferric Chloride ◽  
Ph Value ◽  
Raw Materials ◽  
Color Removal ◽  
Petrochemical Plant ◽  
Water And Wastewater Treatment ◽  
Turbidity Removal ◽  
Iron And Steel ◽  
Composite Coagulant

Coal gangue is a kind of waste from coal mine processing. Polyaluminium ferric chloride (PAFC), a new type of inorganic composite coagulant, was prepared by using the waste from the Mineral Bureau of Yanzhou, China, hydrochloric acid and calcium carbonate as raw materials. The relationship between the stability of ferric ion and the ionic strength of solution was investigated. The zeta potential of PAFC hydrolysis products of PAFC and the coagulation performances under different pH value were discussed. The turbidity removal properties of PAFC, polyaluminium (PAC) and polyferric sulfate (PFS) were compared, and the color removal effect of PAFC for the wastewater containing suspended dyes was also tested. In addition, the coagulation performance of PAFC for actual wastewaters from petrochemical plant, iron and steel plant, and coal mining processing was evaluated. The experimental results suggest that PAFC took a maximum value of zeta potential at about pH 5.8 on the positive side. Compared with PAC, PAFC gives better turbidity removal performance in the range of pH from 7.0 to 8.4. PAFC gives good color removal performance on suspension dyes. PAFC also gives good wastewater purifying results for the actual wastewater. Therefore, PAFC is a high-effect and stable water treatment agent.

scholarly journals Performance evaluation of chemical coagulation process to treat bagasse wastewater: modeling and optimization

2016 ◽  
Vol 18 (1) ◽  
pp. 99-104 ◽  
Author(s):  
K. Thirugnanasambandham ◽  
V. Sivakumar ◽  
K. Shine
Keyword(s):  
Ferric Chloride ◽  
Treatment Process ◽  
Operating Cost ◽  
Settling Time ◽  
Turbidity Removal ◽  
Chemical Coagulation ◽  
Pareto Analysis ◽  
Coagulation Process ◽  
Order Polynomial ◽  
Agitation Time

Abstract In this present study, chemical coagulation process (CC) treatment process was investigated under different conditions such as pH, ferric chloride dose, agitation time and settling time to treat bagasse wastewater using response surface methodology (RSM). The outcomes were evaluated using Pareto analysis of variance (ANOVA) and second order polynomial models were created with the aim of being able to predict the responses. Ideal conditions were observed to be as per the following: agitation time of 25 min, pH of 7, ferric chloride dose of 6 g/L and settling time of 60 min. Under these conditions, turbidity removal of 62%, COD removal of 67%, TDS removal 53% and sludge production of 32 mL/L were obtained with operating cost of 3.50 Rupee/L. The mechanism of CC was analyzed using XRD spectrum and founds to be adsorption.

scholarly journals PRODUCTION AND STABILITY OF MYCO-FLOCCULANTS FROM LENTINUS SQUARROSULUS RWF5 AND SIMPLICILLIUM OBCLAVATUM RWF6 FOR REDUCTION OF WATER TURBIDITY

2018 ◽  
Vol 19 (1) ◽  
pp. 48-58
Author(s):  
Nessa X Jebun ◽  
Abdullah Al Mamun ◽  
Md. Zahangir Alam ◽  
Raha Ahmad Raus
Keyword(s):  
Mixed Culture ◽  
Removal Rate ◽  
Production Optimization ◽  
Screening Tests ◽  
Malt Extract ◽  
Water And Wastewater Treatment ◽  
Turbidity Removal ◽  
Single Culture ◽  
Inoculum Dose ◽  
Wide Range

The production and stability of two novel myco-flocculants produced by river water fungus (RWF) were investigated. Screening tests were conducted to find suitable nutrients, pH, nutrient concentration, inoculum dose, and stability for two myco-flocculants L. squarrosulus (RWF5) and S. obclavatum (RWF6). The strains showed good flocculating activity in reducing turbidity of kaolin suspension while malt extract was used as nutrient source. Supernatants of RWF5 and RWF6 were able to reduce turbidity from 900±10 NTU to 46 NTU (95%) and 195 NTU (78%), respectively. In order to enhance the production, optimization of cultivation conditions were studied using a one-factor-at-a-time (OFAT) method. L. squarrosulus (RWF5) reduced 96% of turbidity at optimum conditions, comprising of 0.1% (w/v) malt extract, 3% (v/v) inoculum dose, and initial pH 7.0 for 6 days. The results of the compatible mixed culture showed good flocculation activity at 88% compared to a single culture of S. obclavatum at 78%. On the other hand, L. squarrosulus showed better turbidity reduction in the single culture rather than the mixed culture. The stability of L. squarrosulus and S. obclavatum supernatants showed excellent turbidity reduction over a wide pH range of 4-8 with the maximal flocculation rate of 96% and 90%, respectively, at pH 7.0. They also exhibited high turbidity removal ability in a temperature range of 4 oC – 55 oC for 24h with a maximum turbidity removal rate of 96% (RW5) and 87% (RW6) at 25 oC. Time stability of the L. squarrosulus supernatant showed good turbidity removal potential at above 90% at room temperature (28± 2 oC) and 85% at low temperature (4 oC) for 12 days. The high flocculating rate of the myco-flocculants and their good stability under wide range of temperature indicated their potentiality as biodegradable flocculants for water and wastewater treatment industry. ABSTRAK: Keberhasilan dan kestabilan dua myco-gumpalan baharu oleh kulat air sungai (RWF) telah dikaji. Ujian penapisan telah dijalankan untuk mencari nutrien sesuai, pH, kepekatan nutrien, dos inokulum dan kestabilan dua myco-gumpalan L. squarrosulus (RWF5) dan S. obclavatum (RWF6). Rantaian menunjukkan aktiviti gumpalan yang baik dalam mengurangkan kekeruhan air sungai dengan penggantungan koalin di mana ekstrak malt telah digunakan sebagai sumber nutrien. Larutan supernatan RWF5 dan RWF6, masing-masing mampu mengurangkan kekeruhan dari 900±10 NTU kepada 46 NTU (95%) dan 195 NTU (78%). Bagi meningkatkan pengeluaran, keadaan optimum bagi menggalakkan hasil telah diselidiki menggunakan kaedah Satu Faktor pada Tiap Masa (OFAT). Pada takat optimum, L. squarrosulus (RWF5) mengurangkan 96% kekeruhan, ianya terdiri daripada ekstrak malt 0.1% (w/v), dos inokulum 3% (v/v) dan pH awal 7.0 selama 6 hari. Keputusan kultur campuran yang sesuai menunjukkan aktiviti penggumpalan yang baik pada 88% berbanding kultur sendirian S. obclavatum pada 78%. Pada waktu sama, L. squarrosulus menunjukkan pengurangan kekeruhan yang lebih baik dalam kultur sendirian berbanding kultur campuran. Kestabilan larutan supernatan L. squarrosulus dan S. obclavatum menunjukkan pengurangan kekeruhan yang sangat baik pada pH yang luas iaitu 4-8 dengan kadar maksimum kekeruhan pada 96% dan 90%, pada pH 7.0 masing-masing. Keduanya menunjukkan kebolehan penyingkiran kekeruhan yang tinggi pada skala suhu 4 oC – 55 oC selama 24 jam dengan kadar nyah kekeruhan maksimum pada 96% (RW5) dan 87% (RW6) pada suhu 25 oC. Kestabilan masa larutan supernatan L. Squarrosulus menunjukkan potensi penyingkiran kekeruhan terbaik atas 90% pada suhu bilik (28± 2 oC) dan 85% pada suhu rendah (4 oC) selama 12 hari. Kadar gumpalan yang tinggi oleh myro-gumpalan dan kestabilan yang baik pada julat suhu yang luas menunjukkan potensinya sebagai agen biodegradasi gumpalan kepada air dan industri rawatan loji air.

scholarly journals Effect of Praestol as a Coagulant-Aid to Improve Coagulation-Flocculation in Dye containing Wastewaters

2015 ◽  
Vol 18 (1) ◽  
pp. 38-46 ◽  
Keyword(s):  
Ionic Strength ◽  
Aqueous Solutions ◽  
Removal Efficiency ◽  
Dye Removal ◽  
Settling Time ◽  
Solution Ph ◽  
Polyaluminum Chloride ◽  
Flocculation Process ◽  
Flocculation Time

<div> <p>This study was conducted to investigate the effect of praestol, as a coagulant-aid, to improve coagulation-flocculation process in the removal of disperse red 60 from aqueous solutions. The effect of various parameters including coagulants dose (10-1000 mg l<sup>-1</sup>), praestol dose (0-1000 mg l<sup>-1</sup>), solution pH (3-11), initial dye concentration (100-500 mg l<sup>-1</sup>), flocculation speed (30-60 rpm), flocculation time (15-30 min), settling time (5-60 min) and ionic strength (0-6 mg l<sup>-1</sup>) was evaluated on the dye removal. The dye removal efficiency was substantially increased by using praestol in the concentration of 80 mg l<sup>-1 </sup>and 400 mg l<sup>-1 </sup>for coagulation with alum and polyaluminum chloride (PACl), respectively. The maximum dye removal by alum coupled with praestol (Al-P) and PACl coupled with praestol (PA-P) was found to be 97.8% and 98.7%, respectively that were occurred at pH 7. The results showed that the application of PA-P or Al-P can be effectively used to remove disperse red 60 (DR 60) in aqueous solutions.</p> </div> <p>&nbsp;</p>

scholarly journals Removal of COD and SO42− from Oil Refinery Wastewater Using a Photo-Catalytic System—Comparing TiO2 and Zeolite Efficiencies

Water ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 214 ◽  
Author(s):  
Emmanuel K. Tetteh ◽  
Elorm Obotey Ezugbe ◽  
Sudesh Rathilal ◽  
Dennis Asante-Sackey
Keyword(s):  
Reaction Time ◽  
Catalytic System ◽  
Uv Light ◽  
Operating Conditions ◽  
Oil Refinery ◽  
Interactive Effects ◽  
Refinery Wastewater ◽  
Mixing Rate ◽  
Water And Wastewater Treatment ◽  
Oil Refinery Wastewater

Advanced oxidation processes (AOPs) have many prospects in water and wastewater treatment. In recent years, AOPs are gaining attention as having potentials for the removal of different ranges of contaminants from industrial wastewater towards water reclamation. In this study, the treatability efficiencies of two photo-catalysts (TiO2 and zeolite) were compared on the basis of the removal of chemical oxygen demand (COD) and SO42− from oil refinery wastewater (ORW) using photo-catalytic system. The effects of three operating parameters: catalyst dosage (0.5–1.5 g/L), reaction time (15–45 min), mixing rate (30–90 rpm) and their interactive effects on the removal of the aforementioned contaminants were studied using the Box–Behnken design (BBD) of response surface methodology (RSM). Statistical models were developed and used to optimize the operating conditions. An 18 W UV light was incident on the system to excite the catalysts to trigger a reaction that led to the degradation and subsequent removal of contaminants. The results obtained showed that for almost the same desirability (92% for zeolite and 91% for TiO2), TiO2 exhibited more efficiency in terms of mixing rate and reaction time requirements. At the 95% confidence level, the model’s predicted results were in good agreement with experimental data obtained.

Studies in polymerization XI. Reactions between polymer radicals and ferric chloride in non-aqueous media

1957 ◽  
Vol 239 (1217) ◽  
pp. 214-229 ◽  
Keyword(s):  
Electron Transfer ◽  
Ferric Chloride ◽  
Rate Constants ◽  
Aqueous Media ◽  
Practical Method ◽  
General Treatment ◽  
Ferrous Chloride ◽  
Styrene Polymerization ◽  
Induction Periods ◽  
Dimethylformamide Solution

The polymerizations of acrylonitrile, methacrylonitrile and styrene have been studied in NN -dimethylformamide solution at 60°C in the presence of ferric chloride. In each case the participating radicals enter into a termination reaction with the salt, with reduction of the latter to ferrous chloride. The rate constants of these reactions have been evaluated from kinetic observations; styryl radicals are much more reactive towards ferric chloride than either acrylonitrile or methacrylonitrile radicals. This is the expected order if the reactions are of the electron-transfer type. It is shown that estimation of the ferrous salt produced provides a useful practical method for determining the rate of chain starting. In the case of styrene, the reactivity of the radicals is so great that induction periods are observed, from which the rates of chain starting may also be deduced. A general treatment of retarded reactions under certain simple conditions is given and applied to the styrene polymerization.

scholarly journals A comparison of different pilot constructed clarifiers with the purpose of achieving the optimum condition in turbidity removal at water treatment plants in Tehran

2017 ◽  
Vol 12 (3) ◽  
pp. 576-588 ◽  
Author(s):  
Seyed Ahmad Mirbagheri ◽  
Sima Malekmohamadi ◽  
Sheida Sohrabi Nasrabadi
Keyword(s):  
Water Treatment ◽  
Optimum Condition ◽  
Removal Efficiency ◽  
Ferric Chloride ◽  
Flow Rate ◽  
Superior Performance ◽  
Turbidity Removal ◽  
Flow Rates ◽  
Water Treatment Plants

Clarifying is one of the most crucial stages in water treatment at water treatment plants. Determining the type of the clarifier in water treatment plants and using it efficiently is necessary. In this study, a pilot is designed and constructed in which the pulsator, the superpulsator and the accelerator are simulated. For each system, turbidity removal efficiency for different influent turbidities and flow rates were studied and the optimum condition was obtained. The results showed that the superpulsator has a superior performance compared to the pulsator, and the pulsator has a superior performance compared to the accelerator and these differences are more sensible at higher flow rates. Also, the best condition for achieving the highest efficiency for the pulsator and the superpulsator is determined to be at flow rate 3 lit/min for an initial turbidity of 2,500 NTU with alum as the coagulant and the highest efficiency for the accelerator is determined to be at flow rate 3 lit/min for an initial turbidity of 2,500 NTU with ferric chloride as the coagulant. Comparing the turbidity removal efficiency shows that for 67% of the cases, ferric chloride has a better performance as the coagulant compared to alum and increasing the influent turbidity leads to an increase in the removal efficiency. Furthermore, three water treatment plants located in Tehran were studied and their characteristics were compared and suggestions were made to enhance their qualities.

scholarly journals Natural agents as auxiliaries in water clarification: literature review and experimental evaluation

2020 ◽  
Vol 42 ◽  
pp. e44800
Author(s):  
João Paulo Nascimento Armeloni ◽  
Danieli Soares de Oliveira ◽  
Clainer Bravin Donadel
Keyword(s):  
Water Treatment ◽  
Literature Review ◽  
Removal Efficiency ◽  
Process Efficiency ◽  
Human Consumption ◽  
Agricultural Activity ◽  
Water And Wastewater Treatment ◽  
Turbidity Removal ◽  
Water Treatment Process ◽  
Treatment Processes

The increasing demand for water resources (primarily for human consumption and industrial and agricultural activity) is driven by socio-economic development, and population growth. Recent research has been focusing on alternative coagulants based on natural elements, as opposed to the commonly used iron and aluminum salts, for use in water and wastewater treatment processes. In this context, a thorough literature review on alternative coagulants and their application to water treatment processes has been conducted in this work. In addition, three experiments have been conducted with a widely used natural organic coagulant (Moringa oleifera). The alternative clarification system used is the helically coiled tube flocculator (HCTF), with high turbidity removal efficiency and low processing times. A comparative analysis of the turbidity reduction over time was performed with samples collected after 600, 900, 1200, 1500, 1800, 2100, 2400, and 2700 s from the hydraulic circuit. The process efficiency using the proposed alternative coagulant reached 95.3% (after 1800 s). The turbidity removal efficiency remained almost constant after 1800 s, with variations below 1%. These results prove that natural alternative agents can be powerful tools in the water treatment process, with efficiency values exceeding those obtained using chemicals (e.g., aluminum sulphate) as coagulant/ flocculant agents.

Research on the Treatment of Xanthate Wastewater by Flocculation Process

2013 ◽  
Vol 807-809 ◽  
pp. 1326-1329
Author(s):  
Jing Zhu ◽  
Xiao Xia Song ◽  
Fei Liu ◽  
Tian Xiang Li
Keyword(s):  
Environmental Pollution ◽  
Settling Time ◽  
Initial Ph ◽  
Flocculation Process

As the widely used collector, environmental pollution and toxicity of xanthates have got more and more concerns. In the present work, the flocculation process had been used to treat xanthate wastewater. The results showed that Al2(SO4)3 was the optimal flocculant. At the conditions of dosage of 0.1mol·L-1Al2(SO4)3 0.5 mL, the initial pH 6.5, vibrating time 90 min and settling time 120 min, sodium isobutyl xanthate was removed nearly up to 100%.

Sign in / Sign up

Export Citation Format

Share Document