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Various technologies thus have been developed recently to treat selenium contaminated water to reduce its environmental impacts. This work provides a critical …
However, acute toxicity caused by high selenium intake has been observed in laboratory animals and in animals grazing in areas where high selenium levels exist in the soil. The US EPA has established the MCL for selenium at 0.05 mg/l. Treatment of Selenium Anion exchange can reduce the amount of selenium in drinking water by 60 - 95%.
Highlights. •. Se legislative limits - 50 μg/L portable water and 1–2 μg/L in surface waters. •. The ongoing research mainly focus on adsorption and bioreactors. •. …
This study reviews the reported techniques for Se removal from water and wastewater, including adsorption, biological treatment, microbial reduction, bioreactors, …
The National Primary Drinking Water Regulations ( NPDWR) are legally enforceable primary standards and treatment techniques that apply to public water systems. Primary standards and treatment techniques protect public health by limiting the levels of contaminants in drinking water. Printable version: Complete NPDWR Table.
On the basis of the fact that algae have the ability to volatilize substantial quantities of selenium (Se), we investigated the concept of including an algal pretreatment unit into a constructed wetland system for the removal of Se from river water entering the Salton Sea. Of six different algal strains tested, the most effective in terms of Se …
This study summarized startup of an actual water treatment plant with a process scheme that had never been designed or operated at this scale. ADW nitrate ( NO 3 − ) and dissolved oxygen ( O 2 ( aq ) ) concentrations largely dictated the externally dosed carbon (EDC), or glycerin dose, which served as the electron donor to achieve selenate ...
The discharge of selenium contaminated water into the environment from industrial processes is a topic of regulatory (WHO – 40 μg/L, EU – 10 μg/L), environmental and health concern. The removal of selenium from water is complex, determined by its speciation and often expensive due to the characteristics of the wastewater and the …
Selenium removal from water using adsorbents: A critical review. 2022 Feb 15;424 (Pt C):127603. doi: 10.1016/j.jhazmat.2021.127603. Epub 2021 Oct 28. Kerry N …
1.1. Requirements and Natural Sources of Selenium. Selenium can be available both in organic compounds (selenomethionine and selenocysteine) and in inorganic compounds (selenite and selenate) [].Considering that the organic form has better absorption, it seems to be the preferable formulation for supplementation or treatment …
Various treatment technologies such as precipitation and coagulation, adsorption, membrane separation, chemical and electrochemical reduction, bioremediation, and phytoremediation thus have been developed and applied to remove selenium from …
Selenium speciation of the influent and effluent water is a key factor for selection of an appropriate technology. Removal of selenite can occur with iron co- precipitation, a conventional physical/chemical process. Selenate removal, on the other hand, is more challenging and cannot be addressed with conventional water treatment …
Any given wastewater can contain various selenium species with different solubility, toxicity and oxidization states that react differently to treatments and water temperature, and compete with other constituents. One of the most common species, selenium IV, is relatively easy to remove with traditional water treatment technologies.
the impact of water treatment on the selenium content of drinking water. Given that treated wastewater is discharged into surface waters and can become a secondary source of selenium in treated water, the extent to which wastewater treatment affects the final selenium content was also analyzed. 2. Materials and Methods 2.1. …
Aluminum-based water treatment residuals (WTR) can adsorb water-and soil-borne P, As(V), As(III), and perchlorate, and may be able to adsorb excess environmental selenium. WTR, clay minerals, and amorphous aluminum hydroxide were shaken for 24 hours in selenate or selenite solutions at pH values of 5 to 9, and then …
Selenium Removal for Electrical Utilities. SeQuester can be employed to remove selenite and selenate from power plant flue gas desulfurization (FGD), ash-sluicing, ash pond, and landfill leachate wastewaters. It also reduces the concentration of other priority pollutants in these water streams under standard operating parameters.
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 …
Desalter wash water originating from the sour water stripper is responsible for most of the selenium contribution to refinery wastewater. It has been found that treating low-flow, high-concentration isolated …
10 Citations. Abstract. After major pollution by nitrates and pesticides, soils and groundwater in some parts of the world are now facing the emergence of a third …
The water treatment based on using adsorbent material to remove the contaminants from the aqueous medium is considered eco-friendly and low-cost for remediation of selenium, thus cleaning and ...
Keywords: selenium, drinking water, treatments, bibliometric analysis, research trends. 1. Introduction. Selenium (Se), with atomic number 34, is a member of group 16 of the periodic table and thus belongs to the chalcogens. The position between the nonmetal sulfur and the metalloid tellurium determines the mainly nonmetallic properties …
Up to day, many treatment technologies have been developed to alleviate noxious effects of selenium in water and they can be classified by different criteria. According to the change of valence states of Se in the treatment processes, this review allocates the treatment technologies for selenium in water into three categories (Fig. 2).
Precipitation is a commonly used treatment method, but requires large chemical input and produces unstable sludge as a waste product. To reach a level of 5ppb, a combination of treatment technologies is usually required. Clean TeQ Water is exploring the application of its proprietary technologies for selenium removal and conversion to a solid ...
This section describes the full-scale selenium treatment biological techniques that are targeted at treating wastewater containing selenium oxyanions. In a variety of ... the first full-scale agricultural drainage water treatment plant with higher saline content was demonstrated using anaerobic GAC, and bioreactors operated for 1062 days ...
Selenium (Se) has become an increasingly serious water contamination concern worldwide. It is an essential micronutrient for humans and animals, however, can be extremely toxic if taken in excess. Sorption can be an effective treatment for Se removal from a wide range of water matrices. However, des …
In conclusion, water is one of the essential substances for human survival, and high quality water leads to a healthy life. The influence of human activities and natural factors on the selenium content in water bodies should not be underestimated. Therefore, proper treatment of selenium-contaminated water bodies is crucial. 3.
What Is Selenium? Selenium is a mineral found in the soil. It naturally appears in water and some foods. While people only need a very small amount, selenium plays a key role in their metabolism.
Selenium has emerged as a contaminant of concern, which has natural and anthropogenic sources. Treatment of aqueous selenium levels to achieve stringent regulatory water limits in the range of from 5 to 50 μg Se/L poses a challenge.Two anionic forms of inorganic selenium are Se(IV) (selenite) and Se(VI) (selenate) which are the …
ECT2 has a broad range of both patented and widely used treatment products, and deep familiarity with addressing critical water treatment challenges caused by 1,4-dioxane, PFOS/PFOA, solvents, and metals – …
The amount of selenium in drinking water is not nutritionally significant in most geographic regions [3,13]. ... However, randomized trials suggest selenium supplementation has little effect on HIV disease progression or treatment. Selenium and Health. This section focuses on six diseases and conditions in which selenium might play a role: ...
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