Biological filtration for removal of arsenic from drinking water

Pokhrel, D.; Viraraghavan, T.

doi:10.1016/j.jenvman.2009.01.004

Cited by 46 publications

(22 citation statements)

References 43 publications

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“…As an example, crystalline Fe III oxides can be microbiologically reduced to Fe II oxides via colloidal hydroxides [125,126]. Thus, beside abiotic processes, biotic processes also contribute to decontamination in Fe 0 filters and should also be considered.…”

Section: Biological Mediated Processes In Fe 0 Filtersmentioning

confidence: 99%

Technologies for Decentralized Fluoride Removal: Testing Metallic Iron-based Filters

Ndé-Tchoupé

Crane

Mwakabona

et al. 2015

Water

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Since the realization in the 1930s that elevated fluoride concentrations in drinking water can have detrimental effects on human health, new methods have been progressively developed in order to reduce fluoride to acceptable levels. In the developing world the necessity for filtration media that are both low-cost and sourced from locally available materials has resulted in the widespread use of bone char. Since the early 1990s metallic iron (Fe 0 ) has received widespread use as both an adsorbent and a reducing agent for the removal of a wide range of contaminant species from water. The ion-selectivity of Fe 0 is dictated by the positively charged surface of iron (hydr)oxides at circumneutral pH. This suggests that Fe 0 could potentially be applied as suitable filter media for the negatively charged fluoride ion. This communication seeks to demonstrate from a theoretical basis and using empirical data from the literature the suitability of Fe 0 filters for fluoride removal. The work concludes that Fe 0 -bearing materials, such as steel wool, hold good promise as low-cost, readily available and highly effective decentralized fluoride treatment materials.

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Section: Biological Mediated Processes In Fe 0 Filtersmentioning

confidence: 99%

Technologies for Decentralized Fluoride Removal: Testing Metallic Iron-based Filters

Ndé-Tchoupé

Crane

Mwakabona

et al. 2015

Water

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“…The 249 cm −1 and 380 cm −1 belong to the vibration bands of Fe-O, representing lepidocrocite (γ-FeOOH) [20,21]. The small band at 296 cm −1 and also 380 cm −1 are representative of goethite (α-FeOOH) [17,18]. The 690 cm −1 probably represents HFO [21].…”

Section: Corrosive Iron Matter (Cim) Compositionmentioning

confidence: 99%

“…strain B2. These are micro-organisms that, according to the scientific literature, could potentially take part in biological arsenic removal [17]. The period of 19 weeks was given to allow the growth of such organisms in the filter(s) bio-layer.…”

Section: Microbiological Analysesmentioning

confidence: 99%

Comparing Mixed-Media and Conventional Slow-Sand Filters for Arsenic Removal from Groundwater

Śmiech

Tolsma

Kovács

et al. 2018

Water

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Arsenic contamination of groundwater is a major public health concern worldwide. The problem has been reported mainly in southern Asia and, especially, in Bangladesh. Slow-sand filters (SSF) augmented with iron were proven to be a simple, low-cost and decentralized technique for the treatment of arsenic-contaminated sources. In this research, three pilot-scale SSF (flowrate 6 L·h −1 ) were tested regarding their capability of removing arsenic from groundwater in conditions similar to those found in countries like Bangladesh (70 µg As(III) L −1 , 26 • C). From the three, two filters were prepared with mixed media, i.e., sand mixed with corrosive iron matter (CIM filter) and iron-coated sand (ICS filter), and a third conventional SSF was used as a reference. The results obtained showed that the CIM filter could remove arsenic below the World Health Organization (WHO) guideline concentration of 10 µg·L −1 , even for inlet concentrations above 150 µg·L −1 . After 230 days of continuous operation the arsenic concentration in the effluent started increasing, indicating depletion or saturation of the CIM layer. The effluent arsenic concentration, however, never exceeded the Bangladeshi standard of 50 µg·L −1 throughout the whole duration of the experiments.

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“…Generally an EBCT of 10 minutes is required to reduce arsenic from up to 100 g/L down to less than 10 g/L. Due to the strong affinity of arsenate to ferric oxide, feeding ferric in the influent increased the removal efficiency with an increasing Fe/As ratio (Pokhrel and Viraraghavan 2009). A study found filtration columns containing mixture of sand and iron fillings improved removal and were capable of reducing arsenic from 50 to well below 10μg/L with an average of 92% removal (Gottinger 2010).…”

Section: Study Scales Water Qualities Parametersmentioning

confidence: 99%