CASE STUDY
- Location – South Africa
- Product(s) – HDPE Landfill Plastic Liner
- Application – Mining Project
Issue
An important issue for landfills is leachate contamination control. After the landfill starts, the inflow of rainwater, surface water and the decomposition of the garbage itself will produce a large amount of sewage, which we call leachate. This liquid pollutant is high in content, complex in composition and fast infiltrating into the ground, which will cause serious pollution to groundwater for hundreds of years.
Solution
In this case, the landfill plastic liner, also known as HDPE geomembrane liner, is particularly important as the most important barrier in the anti-seepage system. The new imported resin raw material, imported geomembrane production line and strict quality control are the prerequisites for the solid and reliable anti-seepage wall.
HDPE geomembrane is a the cost effective landfill sealing geosynthetic material which has high air tightness, because the geomembrane landfill plastic liner is made of high-density polyethylene particles, and the landfill plastic liner product itself has high impermeability and air permeability, which can effectively block flies and also prevents the growth of insects and bacteria, and also ensures that the odor of garbage in the landfill does not spread out.
Secondly, the geomembrane landfill liner has high impermeability. The geomembrane liner laid on the garbage not only blocks the breeding of flies and bacteria and the spread of garbage odor, but also blocks the external rainwater, dew and other moisture.
Finally, the geomembrane has a long service life as a landfill sealing membrane. The geomembrane liner itself is not easy to decompose. If it is buried in the ground, its service life can reach more than 50 years, and even if it is exposed to the outside, its service life can reach up to 50 years.
BPM South African client undertook a large-scale landfill project, hoping to treat landfill leachate well. BPM recommended HDPE landfill plastic liner specifications to customers and provide customers with installation advice. The setting of reinforcement trenches of HDPE geomembrane liner shall meet the following requirements:
- The distance between the anchor trench and the edge of the slope shall not be less than 800mm.
- The turning point of the anti-seepage system engineering materials should not have a right-angle rigid structure, and should be made into an arc structure.
- The cross section of the staggered ditch shall be calculated according to the paving form and actual situation. The subsoil of the trench shall not be disturbed when the anchor groove is excavated. The bottom of the ditch should be level and free of loose soil. The depth and slope of the trench wall should meet the design requirements. Before backfilling the anchor trench, the bottom of the trench shall not be flooded, and the accumulated water shall be drained in time. The anchoring trench should be backfilled in time, and the quality of the backfill should meet the design requirements.
The structure of the closure covering system should be divided into: exhaust layer, anti-seepage layer, drainage layer and vegetation layer in order from the surface of the garbage dump body to the top surface. The layers of the enclosure cover system shall be selected from the following types:
(1) Exhaust layer: The landfill cover system should be equipped with an exhaust layer, so that the gas pressure applied to the anti-seepage layer is not greater than 0.75kPa. The exhaust layer should be made of coarse-grained porous material with a particle size of 25-50mm, the permeability coefficient is required to be greater than 1×10-2cm/s, and the thickness is not less than 30cm. The gas drainage layer can also use a geocomposite drainage network with equivalent drainage performance.
(2) Anti-seepage layer: The anti-seepage layer should be constructed with a composite geotechnical anti-seepage layer of geomembrane and geotextile.
High-density polyethylene (HDPE) or linear low-density polyethylene geomembrane (LLDPE) with a thickness greater than 0.75mm should be selected, and the permeability coefficient should be less than 1×10-7cm/s. However, geotextiles should be provided on the upper and lower surfaces of the geomembrane.
Benefits
(1) Geomembrane landfill plastic liner can reduce the infiltration of rainwater and other external water into the garbage heap, and achieve the purpose of reducing landfill leachate;
(2) The landfill plastic liner can control the odor emission of the landfill and the release and collection of combustible gas from the upper part of the landfill in an organized manner to achieve the purpose of pollution control and comprehensive utilization;
(3) The landfill liner can inhibit the reproduction and spread of pathogenic bacteria and their communicators, mosquitoes and flies;
(4)The geomembrane landfill liner can prevent surface runoff from being polluted, avoid the spread of garbage and its direct contact with humans and animals;
(5) The geomembrane landfill liner can prevent soil erosion;
(6) The geomembrane landfill liner can promote the stabilization of the garbage heap as soon as possible;
(7) The geomembrane landfill plastic liner can provide a surface that can be landscaped, provide soil for the growth of vegetation, facilitate the reuse of landfill land, etc.
Summary
HDPE geomembrane geomembrane landfill liner is a kind of waterproof barrier material based on high polymer polymer. HDPE geomembrane is made of high-quality virgin resin, the main component is 97.5% high density, about 2.5% carbon black, anti-aging agent, antioxidant, ultraviolet absorber, stabilizer and other auxiliary materials.
The HDPE landfill liner has good resistance to environmental stress cracking and chemical corrosion resistance, good chemical corrosion resistance. It also has a large operating temperature range and a long service life, and is widely used in biogas digesters, tailings storage sites, and channel seepage prevention , Dam seepage prevention subway project, etc.
Specifications of Landfill Plastic Liner for Mining Project in South Africa
- Total HDPE Geomembranequantity – 98,000 squares meters
- Geomembrane Specifications– 2mm
- Each roll size is 7m*50m
About BPM
BPM has been specializing in delivering one stop geosynthetics products and solutions to worldwide customers since its foundation in 2007. BPM had provided many types of effective and state of the art geomembranes, geotextiles, geocells, geosynthetic clay liners (GCLs), drainage boards, geogrids to over 81 countries. Our main customers are from Australia, France, Sweden, UK, Hong Kong, Hungary, New Zealand, Poland, Mexico, Ecuador, Brazil, Pakistan, Bangladesh, Thailand, Vietnam, Malaysia, Indonesia, Singapore, Philippines, Sri Lanka, India, UAE, Saudi Arabia, Qatar, Kenya, Ghana, Ethiopia, Somalia, Nigeria, South Africa, Swaziland, Mongolia, etc.
BPM is not only manufacturing best quality geosynthetic products but also providing professional design and installation service. OEM, ODM, custom development and fabrication are also available. If you have any questions or inquiries, please fill and submit the following form, we will reply as soon as possible.
