How To Remove Arsenic From Water A Proven Method
Arsenic happens in bedrock or soil in the United States including parts of Massachusetts. In New Hampshire, during the 1800s it was mined commercially first.
In 1985 in US arsenic used and it has been imported. The important activities which pass arsenic including coal ash disposal, apple orchard spraying and utilize of some pressure treated wood.
There is no color, taste, and smell of arsenic when dissolving in water though higher concentrations.
So laboratory analysis may be defined the concentration and presence of arsenic water.
Side effects of Arsenic in drinking water
As Arsenic is tasteless and odorless, it is undetected and kept affect the human body like discoloration as well as thickening of the skin, nausea, stomach pain, blindness, partial paralysis, diarrhea and numbness in feet along with hands.
Moreover, long-term of exposure to arsenic may have more chronic symptoms.
Declared by the World Health Organization, long time exposure to inorganic arsenic especially through drinking contaminated water, eating food prepared from this water, eating food irrigated with arsenic water may push to chronic arsenic poisoning. Skin cancer and skin lesions are the most severe effect of arsenic.
Natural Resources Defense Council accomplished a study in 2000 stated that about 56 million people in 25 states drink water having arsenic with having a high risk of cancer.
The number has dropped due to the EPA changing arsenic standard which was normally set in the 1960s; the contamination is still worth carrying protected from – in our drinking water to resist consumption to our bodies.
Technologies For Arsenic Removal
There are some areas where lots of arsenic-contaminated water and have no arsenic sources or contaminated with some other compounds.
Though some areas it is very difficult to remove arsenic from the polluted water.
The measure has taken there for a short time. Lots of technologies are now using to remove arsenic from water.
Many documents are making to experiment with a lot of municipal treatment plants.
Some of the technologies may be used at household level or community. All the techniques rely on some fundamental chemical processes that are told below:
Reactions which lessen oxidize chemicals, removing the chemical form. The reaction does not alter arsenic from the solution but is applied to optimize other systems.
Making dissolved arsenic to mold low solubility solid material like calcium arsenic. You may remove the solid from filtration or sedimentation.
If coagulants are added to make flocks, other dissolved compounds like arsenic may become insoluble or form solids, it is known as co-precipitation.
These solids formed will remain suspended, need removal by liquid or solid separation system especially filtration or coagulation.
Adsorption and ion exchange
Different solid materials, like aluminum hydroxide flocs, and iron have forceful affinity to dissolve arsenic.
Arsenic can strongly attract to sorption sites on the upper part of the solids is fruitfully remove from the solution. Ion exchange may be thought as a special form of adsorption although it is through individually.
Ion exchange involves the alternative displacement of an ion adsorbed to the solid surface by a dissolved ion. There are some other types of adsorption like stronger bonds that are less easily reversed.
Co-precipitation, adsorption, ion exchange and precipitation all transfer the contaminant from the dissolved to a solid phase.
In some cases, solid may be fixed or large, and no solid separation is essential. If you see the solid are in situ, you have to separate it from the water.
Gravity settling may accomplish few of this, but filtration is very useful. People like to use sand filtration for such purpose.
Some synthetic membranes are porous to dissolve compounds but exclude others. It may use as a molecular filter to eliminate dissolved arsenic as long as another dissolve with particulate compounds.
Biological removal processes
To remove many of the above catalyzing you can use bacteria. Little is known about the potential biological removal of arsenic out of the water.
Boiling water may not remove arsenic from the water at all.
To remove arsenic from water most of the established technologies use some of these processes. It may be same time or sequence of time.
All the technologies have added merits of removing undesirable compound with arsenic- it is up to the factor of bacteria, technology, odor, color turbidity, phosphate, hardness, nitrate, fluoride, manganese, iron and some other metals to remove.
Historically, the general technologies of removing arsenic from water have been coagulation by lime softening, metal salts and manganese or iron removal.
As the WHO guideline value for arsenic in drinking water is lowered from 50 to10 µg/L in 1993. Some countries lower the drinking water standard, in some cases to10 µg/L. In January 2001, the USEPA lowers the US drinking water standard from 50 to 10 µg/L.
Coagulation systems are not able to efficiently alter arsenic to the low levels. So, different alternative techniques have been adapted and developed which can remove arsenic from water to a great extent.
The name of these advanced techniques is Reverse Osmosis, Membrane method, Activated alumina etc.
These methods are very fruitful in labor pilot studies; there are some experiences with the full-scale treatment.
Moreover, lots of technologies are under development, some of them give very excellent results.
Under there are main technologies to remove arsenic from water. Besides, there is a brief description of the way to removal efficiency is affected by arsenic speciation and concentration pH and the presence of dissolved constituents.