Onsite Polymer Slurry Treatment and Disposal

For the construction of diaphragm walls, traditionally bentonite slurry is utilised to form a filter cake on the walls of trenches to support earth pressure. It is now becoming more common place for polymer to be used for the same application, this is due to its extended re-usability. However, the end disposal of this liquid still requires consideration.

This contractor and their polymer supplier have done an extensive trial to demonstrate that the concentration of Monomer Acrylmide was residual and explain how robust the treatment process was to prevent raw polymer to spill into the sewer.

Following the submission of a technical note demonstrating the above, they have provided the discharge consent to the supplier and therefore prevented the use of tankers to dispose of the waste polymer

An estimated 333 tankers would have been required to transport the 6,000m3 of polymer slurry waste to a disposal location 12.1miles from the Old Oak Common site. Through being able to destroy the polymer and discharge the resultant liquid into the onsite sewer, this has removed the need for any tankers to dispose of the liquid. Therefore, this has resulted in an estimated saving of 10.42tCO2e.