Sludge Lagoon covers with geosynthetics: Design and special process techniques
Abstract
The construction of a capping system on top of a sludge lagoon is a technically hard task. The weak sediments and their low shear strength afford highly sophisticated and plant optimized solutions. The use of geosynthetics can massively reduce the potential risk of failures and catastrophes for the environment caused by sludge impoundments.
In the past the use of plant specified fabricated geosynthetics and a detailed planned construction work results in cost and time effective solutions. Based on one topical project the main characteristics for choosing the reinforcement, the design and the work schedule will be presented in this paper.
Conclusion
The use of geosynthetics can massively reduce the potential risk of failures for the environment caused
by sludge impoundments.
Different raw materials allow the use of geotextiles in nearly every chemical environment. A lot of
projects worldwide show that each sludge lagoon is unique. Each project has its own specifics
regarding geology, products and construction. This paper focuses on design and construction phases of
sludge lagoon covers considering a specific case of Bitterfeld south sewage ponds.
Geocomposite or wovens have a reinforcing and separating functions and can be sewed in large
panels. Woven geotextiles or geocomposites in the form of large prefabricated panels offer a quick and
safe way to cover lagoons when the sludge was not stabilized sufficiently before deposition. Low
bearing capacity and even an open water table is not a hurdle for this method. Panel sizes of 18.000 m²
have been installed successfully. Larger dimensions should be possible using optimized geotextiles,
installation process and careful planning.