Coal ash disposition facility by using geotextile tubes

摘要

The present article describes the designing works, field tests, execution and rising of a tailing cell for ashes originated in the process of a thermoelectric power plant located in the northeast region of Brazil. These tailings are resulting from mineral coal burn in the process of electrical energy generation. Previously these tailings were disposed in a conventional tailing cell, but, according to operation previsions in the power plant, this cell would get insufficient by the year of 2012. The proposed solution was the use of geotextile tubes filled with the own tailings generated in the plant process, using them to rise the tailing cell capacity without the need of an increased area to do so. In the year 2013 the project design got completed and two rising lines of geotextile tubes were defined as the better combination for the whole conditions, as a result, a higher tailings dam, rising 3 meters, attended the plant needs. Since this kind of tailings are not usually managed as slurry, many other conditions of installation and operation for the geotextile tubes were defined on site and on laboratory, making this project a very innovative one. As the ashes correspond to a dry material with difficult manipulation characteristics, resulted to be very challenging to the responsible technical team, demanding the realization of several tests and measurements. The viability of the proposed solution got verified and approved for further projects in the same field. The installation process of the geotextile tubes began in December of 2013. As seen through the performed tests, the solution was a success, showing itself as both efficient and safe, besides the technical, economical and operational advantages achieved in comparison to the conventional solutions.