Tuesday, September 6, 2011
Just a few biological techniques include:
Phytoremediation: Certain plants and trees are planted where the roots can access ground water. Over time they absorb contaminants and are then destroyed. The movement of water disperses the pollutants over a wide area which can then come into contact with groundwater wells making surface water (like springs) hazardous to humans and animals. The study of this movement is called hydrogeology.
Bioventing: The use of microorganisms to biodegrade organic constituents absorbed in the groundwater.
Biosparging: Uses indigenous microorganisms to biodegrade constituents.
Bioslurping: Combines part of bioventing and vacuum pumping to retrieve the product from the groundwater and soil.
Bioaugmentation: The inoculation of strains which degrade the contaminants.
A few chemical techniques include:
Chemical precipitation: Addition of an agent to a container of water which is stirred to create a reaction.
Carbon absorption: Activated carbon absorbs volatile organic compounds.
Ion exchange: Water passing downward under pressure through a granular medium.
Ozone and oxygen gas injection: Ozone and oxygen is injected into soil and groundwater contamination resulting in surfactant enhanced recovery and aqueous chemical oxidation.
Some examples of physical treatment techniques are:
Air sparging: Blowing air directly into the ground water creating bubbles at the surface. The contaminants are removed by contact with the air.
Dual phase extraction: Using a high-vacuum system to remove both contaminated groundwater and soil vapour.
Pump and treatment: This is one of the most widely used groundwater remediation technologies. The ground water is pumped to the surface where it is treated either chemically or biologically to remove contaminants.
Groundwater treatment is a highly effective weapon in the modern fight for more clean water.
Wednesday, August 17, 2011
Let us tackle the first part: in this kind of purification treatment carbon is used. We are going to take a look at exactly how it is used. Basically carbon is obtained from coal, and things like the shells of peanuts. After that this is heated so that it becomes a different form of charcoal. The passage of gases which are strong oxidising agents through this form of charcoal, at some really high temperatures results in the formation of holes within the charcoal. The better the process is done, the more holes are created.
These holes can be thought of as something like the holes in a sponge, and like a sponge soaks up stuff, so does this form of charcoal. Once the process of making the holes is complete, the charcoal with holes is known as activated carbon, and hence the name activated carbon water treatment.
So what is the treatment exactly? Again the process is actually very simple: the holes that have been created in the carbon act like small pockets, and this gives activated carbon absorbing capabilities. When it is brought in contact with water, and the process of activated carbon water treatment begins, the activated charcoal basically absorbs all the things from water that it can. Carbon forms the basis of organic materials, and it basically helps remove impurities that have an organic nature from the water. It also helps remove chlorine, which is used in the water treatment process to get rid of bacteria, and is responsible for the stench that water has.
This is true for activated carbon, but there are many different carbon fibres, and if they are used they give even better results. For example, a specific type of carbon fibre can help remove lead impurities. This is a very good thing, because lead can be extremely harmful to human health. It can lead to lead poisoning, and also causes many other problems of a rather severe nature. Installing filters in your house, that use this type of carbon fibre to clean water, helps make sure that you get clean, and pure water.