Arsenic removal from high-arsenic water by enhanced coagulation with ferric ions and coarse calcite

High arsenic in natural groundwater in most of the tubewells of the Purbasthali- Block II area of Burdwan district (W.B, India) has recently been focused as a serious environmental concern. This paper is intending to illustrate the statistical modeling of the arsenic contaminated groundwater to identify the interrelation of that arsenic contain with other participating groundwater parameters so that the arsenic contamination level can easily be predicted by analyzing only such parameters. Multivariate data analysis was done with the collected groundwater samples from the 132 tubewells of this contaminated region shows that three variable parameters are significantly related with the arsenic. Based on these relationships, a multiple linear regression model has been developed that estimated the arsenic contamination by measuring such three predictor parameters of the groundwater variables in the contaminated aquifer. This model could also be a suggestive tool while designing the arsenic removal scheme for any affected groundwater.

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Arsenic Removal from Pyrite Cinders by Oxidizing Roasting with Sodium Hydroxide Addition

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.881-883.1655 ◽

2014 ◽

Vol 881-883 ◽

pp. 1655-1659 ◽

Cited By ~ 1

Author(s):

Shao Jun Bai ◽

Shu Ming Wen ◽

He Fei Zhao ◽

Chao Lv

Keyword(s):

Sodium Hydroxide ◽

Steel Industry ◽

Arsenic Removal ◽

Raw Material ◽

Iron Concentrate ◽

Roasting Temperature ◽

Chinese Steel Industry ◽

Iron Bearing ◽

Pyrite Cinders ◽

High Arsenic

A craft of sodium hydroxide roasting-aqueous leaching process is investigated for the treatment of a high arsenic pyrite cinders, a common by-product in vitriol industry. The pyrite cinders, containing 58.27% Fe, and 0.98% As, was conducted for the craft. The results demonstrated that iron concentrate with 58.87% Fe, 0.13% As and 87.40% of arsenic removal percentage was obtained under the optimal conditions (a roasting temperature of 1000°C, a roasting duration of 120 min and a mass ratio of sodium hydroxide to pyrite cinders of 8%).This craft can be used to utilize pyrite cinders and produce qualified concentrate as iron-bearing feed for steel industry, which will help to solve the pollution of pyrite cinders and extend raw material sourcing for Chinese steel industry.

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The Influence of Dosing Modes of Coagulate on Arsenic Removal

Journal of Chemistry ◽

10.1155/2014/617978 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7

Author(s):

Zhibin Zhang ◽

Jinxiang Li ◽

Cuizhen Sun ◽

Yanhao Zhang ◽

Lilong Huang ◽

...

Keyword(s):

Particle Size ◽

Arsenic Removal ◽

Arsenic Speciation ◽

Contaminated Water ◽

Distribution Analysis ◽

Hydrous Oxides ◽

Stretching Vibration ◽

Ft Ir ◽

Single Dosing ◽

High Arsenic

Three different dosing modes, including one single dosing mode and two sequential dosing modes, were applied in high-arsenic contaminated water treatment. The results illustrated that the As (V) soluble and the As (V) nonspecifically sorbed were the insignificant species from Fe-As (V) samples in the sequential dosing mode, while they were higher in the single dosing mode. However, it could be further concluded that the mobility of the Fe-As (V) in sequential dosing mode was greater than that in single dosing mode. Besides, the main arsenic speciation governing the arsenic-borne coagulates was the As (V) associated with poorly crystalline hydrous oxides of Fe in sequential or single dosing mode. Moreover, the particle size distribution analysis indicated that the sequential dosing mode was more prevalent in neutralizing and adsorbing the As (V) compared with the single dosing mode. In the FT-IR spectra, the presence of arsenic was highlighted by a well resolved band at 825–829 cm−1. The positions of the As–O stretching vibration bands were shifted gradually as the dosing mode changed from the single to the sequential. This result could be related to the distribution of arsenic speciation in different dosing modes.

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Family filter with iron-coated sand: solution for arsenic removal in rural areas

Water Science & Technology Water Supply ◽

10.2166/ws.2002.0160 ◽

2002 ◽

Vol 2 (5-6) ◽

pp. 127-133 ◽

Cited By ~ 2

Author(s):

B. Petrusevski ◽

S.K. Sharma ◽

F. Kruis ◽

P. Omeruglu ◽

J.C. Schippers

Keyword(s):

Developing Countries ◽

Rural Areas ◽

Arsenic Removal ◽

Arsenic Concentration ◽

Water Supply Systems ◽

Treatment Unit ◽

Household Level ◽

Point Of Use ◽

Coated Sand ◽

High Arsenic

The presence of arsenic in groundwater is recognised as a threat to public health world-wide and specifically in rural areas of several developing countries due to variety of health-related problems observed in populations ingesting arsenic-containing water. Several arsenic removal technologies suitable mainly for centralised treatment are available or under investigation. However, point-of-use arsenic removal systems, suitable for application at household level appear to be the only feasible solution under conditions prevailing in rural areas of developing countries characterised in general by the absence of centralised water supply systems. Several household level arsenic removal units are commercially available and some of them are currently under testing in Bangladesh. Nevertheless there is still need to develop a more efficient and sustainable point-of-use arsenic removal unit. Very promising results were recently obtained in laboratory experiments with a simple “family filter” with iron-coated sand (ICS) or iron-impregnated granular activated carbon. The objective of this study was to establish methodology for assessment and selection of appropriate ICS for arsenic removal with “family filter”. An additional objective was to optimise and test further “family filter” with selected ICS. Batch and filtration laboratory adsorption experiments were conducted with five types of ICS originating from Dutch groundwater treatment plants and model and natural groundwater with high arsenic concentration. All ICSs tested demonstrated arsenic removal potential with removal efficiencies ranging from 50 to 100%. Short adsorption experiments can be applied to screen the suitability of different ICSs. Adsorption isotherm and filter runs are, however, needed to establish arsenic adsorption capacity of a particular ICS. Contact time was found to be the critical parameter for “family filter” design and performance. The “family filter”, very simple point-of-use treatment unit, equipped with an appropriate ICS demonstrated high arsenic removal potential and could be very attractive for arsenic removal in rural areas of developing countries.

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Arsenic Immobilization by Biological Scorodite Crystallization: Effect of High Ferric Concentration and Foreign Seeds

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.71-73.629 ◽

2009 ◽

Vol 71-73 ◽

pp. 629-632 ◽

Cited By ~ 6

Author(s):

Paula González Contreras ◽

Jan Weijma ◽

Cees N.J. Buisman

Keyword(s):

Arsenic Removal ◽

Removal Rate ◽

Molar Ratio ◽

Biological Oxidation ◽

High Concentration ◽

Kinetics Of Crystallization ◽

Iron Oxidizing Bacteria ◽

Crystallization Effect ◽

Kinetics Of ◽

High Arsenic

Biological scorodite is produced at 80°C and 1g L-1 As5+, using iron oxidizing bacteria Acidianus Sulfidivorans, with a molar ratio Fe/As of 1 and without the use of seeds. We investigated the effect of high ferrous concentration, Fe/As higher than 1, and the use of foreign seeds (gypsum) on biological scorodite crystallization. The use of high ferrous concentrations resulted in a retardation of the time of crystallization due to the high concentration of ferric produced by a high biological oxidation. However, ferrous biological oxidation might be controlled to avoid this effect. The use of seeds did not improve the kinetics of crystallization. Nonetheless, a high arsenic removal rate was observed in the presence of seeds probably as a result of the formation of less stable scorodite.

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