Taldykol Sewer Pond Cleaning by Use of Dewatering Tubes
Location of work/project:
Kazakhstan, Astana, Taldykol
HUESKER Synthetic GmbH
The artificial lake “Taldykol” was located in the south western corner of the Kazakh capital city Astana. Following the opening of the wastewater treatment plant in 1974, the processed sewage was released into the water body. The lake was silting up with organic material and had a foul smell, always being close to eutrophication.
Consequently the “Taldykol remediation plan” was decided upon. The objective was to establish the former two small lakes “Big Taldykol” and “Ulmes” within their historic natural boundaries. The whole project consisted of 5 different phases; including the construction of a new wastewater treatment facility to stop the continuous flow into the lake. The third phase designated “Lake deepening and re-cultivation of earth works” consisted of dredging the artificial super lake and dewatering the sludge using geotextile tubes.
The gravity drainage process ensures the steady removal of water from the sludge in the dewatering tube. The specific opening size of the high-performance woven textile ensures retention of the solid fraction of the sludge while allowing the water to escape from the tube. The first tubes were filled in autumn of 2014, whereas the full-scale operation didn’t start until after the spring of 2015. Phase three was completed in October 2017 after 5.6 million cubic metres of sludge had been dredged and dewatered in 960 SoilTain Dewatering Tubes. After dewatering and consolidation, the tubes were cut open and the highly organic, dried material was used as fertilizer. Prior to the project, detailed sludge analysis and flocculation aid tests were carried out. Based on the results of these preliminary dewatering trials using geotextile tubes, the final design was formulated and the system adopted. The SoilTain Sludge Dewatering system was clearly demonstrated to be the optimal solution for this large-scale project.