Released on = July 2, 2007, 1:51 am

Press Release Author = Papita Saha

Industry = Environment

Press Release Summary = Due to least expensive alternative, landfill has been the
most commonly practiced method for disposal of waste materials. Liners provide the
final line of defuse against groundwater contamination. To dispose any hazardous
waste to a landfill, liner is used which protects the landfill as it a barrier to
fluid movement. The overall objective is to limit the discharge of toxic
contaminants to groundwater. When soil is used as liner materials with cement, lime,
gupsum, bentonite etc as admixture, the transport of the waste & Hazardous material
is decreased & the the contamination reduction is 45 - 98% depending on the
admixture used.

Press Release Body = In Industry Geo-membrane liner are used as liner materials. But
the problems of using these materials are: They are non-biodegradable, so for
disposing these materials are creating problem. These are very costly, unsuitable
for retention of some hydrocarbons & there is a possibility of structural cracking
in liner material. So, one of the alternative way is using clay as liner materials.
The very low permeability of the clay barrier is expected to lengthen the lifetime
of the landfill and slow down the consequent release of contaminants. Low porosity,
slow diffusive transport, high adsorption of cations, and plasticity / swelling is
among the interesting property of clays. Some clay soils have the ability to act as
membrane that restricts the passage of charged solutes. Such membrane behavior also
results in Chemico-Osmosis, or movement of liquid in response to solute
concentration gradient. Both these effects result in reduced solute transport
through a soil barrier for waste contaminant.
It is seen experimentally that using some stabilization agent with soil like
bentonite, cement, lime, gypsum etc the effect of the chemical waste on soil liner
can be reduced to 45 - 98%.

Web Site = http://geocities.com/papitasaha

Contact Details = Papita saha.
Lecturer
ITME College,
West bengal, India
E-mail: papitasaha@gmail.com