Construction of Geomembrane in Landfill Sites

Site Preparation: Before laying the geomembrane, the landfill site needs to be leveled and compacted to ensure that there are no sharp objects, stones, or other obstacles on the site surface that may damage the geomembrane. At the same time, drainage treatment should be carried out on the site, and a proper drainage slope should be set up to facilitate the discharge of leachate.

Laying of Geomembrane: According to the design requirements of the landfill site, the geomembrane should be laid in a certain order and method. Usually, the geomembrane is unrolled by mechanical or manual means. Care should be taken to avoid wrinkles, tears, or damage to the geomembrane. During the laying process, the geomembrane should be closely attached to the site surface, and air gaps should be minimized as much as possible.

Welding and Connection: The connection between geomembranes is usually achieved by welding to ensure the sealing performance and strength of the connection part. Before welding, the edges of the geomembrane need to be cleaned and processed, and then professional welding equipment is used for welding. After welding, a quality inspection should be carried out on the welded part, such as using methods like air pressure testing or vacuum testing to ensure that there is no leakage at the welded joint.

Anchoring and Fixing: In order to prevent the geomembrane from shifting or being blown up during use, it is necessary to anchor and fix the geomembrane. Common anchoring methods include setting up anchoring trenches around the landfill site, burying the edges of the geomembrane in the trenches and compacting them; or using sandbags, stones, and other heavy objects to fix the edges of the geomembrane.

Construction of the Protective Layer: After the geomembrane is laid, a protective layer usually needs to be laid on its surface to protect the geomembrane from sunlight ultraviolet radiation, mechanical damage, and human damage. The protective layer can be made of materials such as soil layers, sand layers, gravel layers, or geotextiles, and the selection and construction should be carried out according to the specific situation and design requirements of the landfill site.

Installation of the Leachate Collection System: The leachate collection system, including collection pipes, inspection wells, and other facilities, also needs to be installed on the geomembrane. The collection pipes are usually laid in the protective layer above the geomembrane to facilitate the collection and discharge of the leachate generated in the landfill site. During the installation of the leachate collection system, it is necessary to ensure that the connections of the pipes are tight and unobstructed, and to avoid leakage and blockage.