Q. Explain about Bentonite slurry and polymeric slurry?

For the construction of diaphragm walls, bentonite slurry is generally used to form a filter cake on walls of trenches to support earth pressure. Usage of bentonite solely is based on its thixotrophic gel viscosity to provide support.

However the cost of polymer is normally more expensive than bentonite, usage of polymer is increasing since polymer is normally infinitely re-usable and very small amount of polymer is generally essential for construction works. Disposal cost of bentonite is quite high whereas the disposal of polymer may be readily conducted by adding agglomerator.