Methods for selenium removal from contaminated …
For industrial scale selenium removal, the first possible method is iron coprecipitation and adsorption, further coupled, if necessary, with coagulation …
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Laboratory-scale bioreactors for soluble selenium removal from selenium
Laboratory-scale bioreactors were constructed to investigate their applicability for recovery of soluble selenium from industrial wastewater. Microbial reduction of soluble selenium into elemental selenium is the key reaction because, as a result of its insoluble characteristics, it can be removed easily from the aqueous phase.
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Biological selenate and selenite reduction by waste
Biological reduction of selenium oxyanions is widely used for selenium removal from wastewater. The process is, however, limited by the availability of a suitable, efficient and low cost electron donor. ... H 2 is suggested to be the best electron donor for other similar oxyanion such as for sulfate reduction at industrial scale in comparison ...
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Recent advances in technologies for removal and recovery of selenium
Selenium (Se) is distributed into different environmental compartments by natural and anthropogenic activities, and generally discharged in the form of selenate [S e O 4 2 −] and selenite [S e O 3 2 −], which are both toxic.Physical-chemical and biological treatment processes have been reported to exhibit good treatment efficiencies for Se …
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Frontiers | Selenite elimination via zero-valent iron …
Cost-effectively improving the performance of biochar is essential for its large-scale practical application. In this work, the agro-industrial by-products copper slag and tobacco straw were employed for …
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Review on environmental selenium: Occurrence, public …
The removal of selenium was performed in a pilot-scale fluidized-bed biofilm reactor (FBBR) containing 155–588 µg/L (360 µg/L average) of selenate, 800 mg/L sulfate, and 31 mg/L nitrate-nitrogen from mining wastewater (Gay et al., 2012). In this study, the HRT was varied between 60 and 120 min at 11.4 and 5.7 Lpm flow rates, with the ...
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Chapter 6 Biological treatment technologies
project milestones in the development of biological selenium removal at full scale in North America between 1999 and 2018 are presented in Figure 6.3. The ABMet ® process was developed in the ...
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Frontiers | Evaluation of selenite reduction under salinity and …
Current microbial reduction technologies have been proven to be suitable for decontaminating industrial wastewaters containing high concentrations of selenium (Se) oxyanions, however, their application is strictly limited by the elemental Se (Se0) accumulation in the system effluents. In this work, a continuous-flow anaerobic …
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Effect of temperature on selenium removal from wastewater by …
The effect of temperature on selenium (Se) removal by upflow anaerobic sludge blanket ... 2009). However, their application in full-scale systems is limited due to low efficiencies or economic reasons. The microbial reduction of Se oxyanions to elemental Se in bioreactors is a promising alternative to treat Se rich wastewater (Chung et al ...
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Water | Free Full-Text | Environmental Impacts of …
Physical treatment methods used on an industrial scale for selenium removal include membrane filtration, media filtration, and ion exchange. These are conventional methods employed for industrial …
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Biological Removal of Selenate and Selenite from …
The shape, size and location of these selenium nanoparticles along with the selenium oxyanion removal efficiency depend on the operating parameters. Moreover, …
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A critical review on Selenium removal capacity from …
By understanding the strengths and limitations of various biosorbents, this review is expected to o scale-up targeted research on Se removal, promoting the …
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(PDF) Biological treatment technologies
The cost of constructing full-scale active selenium treatment facilities like those. described in Section 6.4 can be significant. Active biological selenium removal. plant projects can cost as ...
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Biological transformations and removal of selenium in …
Iron coprecipitation was used in bench-scale tests to remove selenium from stripped sour water generated by two petroleum refineries. Chlorine dioxide and hydrogen peroxide were found to convert selenocyanate in the stripped sour water to selenite, which can be removed by iron coprecipitation. An iodometric titration procedure was developed …
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Selenium Removal from Industrial Wastewater | Water …
The data from another bench-scale test outlines an example of selenium reduction potential from oil refinery wastewater: 24.4 μg/L from untreated wastewater; . 2.5 μg/L from treated wastewater. In many states (California, for example), groundwater is being regulated for selenium discharge, creating challenges for industrial facilities.
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REPORT State-of-Knowledge on Selenium …
The survey results documented thirty (30) full-scale selenium removal systems have been installed predominantly in North America from 2007 to 2018, with design flow rates ranging from 75 gpm to 2,800 gpm (i.e., 410 m3/day to 15,260 m3/day). …
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Selenium: environmental significance, pollution, and biological
A high total selenium concentration was noticed in the effluent of the FBR effluent due to biofilm detachment. Additional liquid–solid separation is needed to remove the biomass and biogenic selenium from the effluent. A bench-scale FBR was used to treat mining water with 5 to 100 mg L − 1 NO 3 − -N and 20 to 300 μg Se L − 1.
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Kemess Selen-IX™ Plant for Selenium Removal | Clean50
As the first full-scale water treatment plant to utilize a non-biological treatment system for the removal of selenium in compliance with water quality regulations, the Kemess Selen-IX™ Plant in Northern BC achieves results other systems can only dream of. Selenium is essential to all life forms in trace amounts but at high concentrations, it is harmful to fish …
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A review on environmental selenium issues | SN Applied …
For instance, the full-scale application systems in selenium removal include fixed bed biological filters, constructed wetlands and reverse osmosis. Table 2 below gives a glimpse of the classes of selenium remediation technologies with the corresponding examples that are partly detailed in Table 3 including the advantage and disadvantage as ...
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A potent insight into the microalgal and surface-modified
C. vulgaris was used in the selenium removal process, ... Researchers have great challenges when they consider using it in large-scale removal. The produced and selected strains should be stable and highly resistant to heavy metal contaminants. Some of the metal ions inhibit microalgal growth, whereas others could promote …
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Selenium Removal Key to Water Reuse
levels. Scale inhibitor is added to control calcium sulfate scale. The original concept involved feeding RO concentrate to the ABMet reactors to ensure the selenium content of water sent to evaporation ponds would be less than 10 ppb. During initial startup, the system went through multi-day periods when the RO concentrate remained in
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Western Water and Power Solution Bulletin
A bench-scale test was conducted in 2007 that demonstrated selenium removal rates of 92 to 98 percent. During the bench-scale tests, pretreatment concentration selenium ranged from 20 to 70 micrograms per liter. The pilot-scale test was conducted in 2008-09, and its primary objective was to achieve high selenium
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Selenium Removal Key to Water Reuse
Removing the selenium to a very low level (less than 5 ppb) in the ABMet reactors is necessary to achieve less than 10 ppb of selenium in the RO concentrate. Realizing less …
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Methods for selenium removal from contaminated waters: a …
The removal of selenium from drinking water, wastewater, and industrial discharges can be accomplished using techniques based on zero-valent iron, iron-oxy-hydroxides, supported materials ...
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Concerns with Passive Anaerobic Bioreactors for Selenium Removal …
Passive anaerobic bioreactors (PABs) are flow-through trenches filled with plant substrates that serve as energy and carbon sources for bacteria that carry out water treatment processes. In this study, the effectiveness of PABs to bioreduce selenate to insoluble Se (0) and improve the water quality of coal slurry impoundment liquid (CSL) …
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An economical strategy towards the managing of selenium …
A case study on selenium removal from water utilizing nano-scale zero-valent iron was also discovered by Huang et al. (2021). They demonstrated that the main Se (IV)-nZVI reaction mechanism is the chemical reaction of Se (IV) to Se (0). ... Selenium removal increases was achieved for the clay composites in which two polymer layers …
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(PDF) Bioremediation of Selenium Contaminated …
Numerous treatment technologies for Se removal based on physical and chemical processes have been tested at bench scale, pilot scale, and full scale, and several are commercially available ...
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Past, present and future for treating selenium-impacted water
A full-scale hybrid application (RO + biological treatment) was designed to reduce selenium (30 µg L −1 ) and total dissolved solids (TDS) (5000-8000 mg L −1 ) from a Western US metal mine ...
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Recent advances in technologies for removal and recovery of selenium
The most detailed pilot study of the use of CW for selenium removal was conducted recently by Zhao et al. (2020a, ... Moreover, many technologies have reported obtaining remarkable removal efficiencies in laboratory-scale setups, but most of these technologies render poor performance when fed with real (waste)waters. Technologies …
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Sorption of Se(IV) from aqueous solution by wheat bran
However, the selenium removal by wheat bran gives rise to several problems. Firstly, the organic compounds, such as starch could leach from wheat bran in the adsorption process and may cause a secondary pollution. ... (IV) at 25 °C is higher than that of nanocrystalline hydroxyapatite prepared from fish scale waste (1.94 mg/g), commercial ...
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