Geo-Synthetic
Clay Liner and Method of Manufacture Thereof
Background
Geo-synthetic Clay Liners (GCLs) are pre-fabricated
hydraulic barriers consisting of a layer of bentonite sandwiched
between two layers of Geotextile or fixed to a layer of Geomembrance
using an adhesive. They are used as a replacement of thick
and difficult to construct Compacted Clay Liners (CCL) in
land filling systems, land cover fill systems, water proofing
systems, under water installations, environmental protections,
geomembrane protections, etc. The basic function of a OCL
is to provide an impermeable barrier to water and water soluble
liquid. Present practice of making OCL has drawbacks like
non-uniformity of bentonite layer and low shear strength.
Keeping this in view a new method has been developed for making
OCL with improved quality.
Introduction
Bentonite powder is first encased in a specially
prepared multi-cellular packets made of water soluble polymer
films. The films are prepared by using polymers such as polyvinyl
pyrrolidone, poly acrylamide, poly acrylic acid, polyvinyl
alcohol, etc Placing dry bentonite powder in water soluble
film packets prevent the bentonite being lost through perforation
in the geotextile during transportation and handling. At the
same time, when OCL so prepared comes in contact with water/leach
ate, the water soluble film dissolves and allows the bentonite
to swell uniformly to form an impermeable layer. Such packets
are then covered on two sides by geotextile materials and
the assembly is attached together. The encasing of bentonite
in multi-cellular packets enable distributing a pre-determined
quantity of powder evenly over an unit surface of OCL.
Special Features
OCL prepared by this improved has the following
advantages: Can be used successfully and efficiently on flat
surface as well as slopes with varied degree of gradient;
Possess improved structural integrity without the use of glue/adhesive,
needle punching, compacting and other similar means; Possess
improved structural integrity without the use of glue/adhesive,
needle punching, compacting and other similar means; No mixing
of of any chemical compounds with the clay; Logistic and environment
friendly; Economically feasible and commercially marketable
product.
Prospective Users
To provide an impermeable barrier to water
and water soluble wastes; To create low permeability layer
for use in waste containment sites and manmade bodies of water
, as seepage resistant structure; As replacement of thick
and difficult to construct Compact Clay Liners (CCL) in land
filling systems, water proofing systems, under water installations,
geomembrane protections, environmental protections, etc. To
act as a water barrier shielding in the foundation
Managing Director
Foundation for Innovation and Technology Transfer (FITT)
Indian Institute of Technology, Delhi
Hauz Khas, New Delhi-110016, INDIA
Tel : 91-011-26597167, 26857762, 26581013, 26597153
Fax : 91-011-26851169
E-mail : drkdpn@gmail.com
