A wide range of industries depend on high quality, durable, impermeable geomembranes, wherever there’s a need for dependable containment. Those situations might include preserving clean water, or containing wastewater, stormwater, and many types of hazardous materials. After all, liquids tend to travel easily, whether they’re flowing, pooling, or evaporating. If their escape could cause environmental damage or financial losses, it makes good business sense to use liners and other sheet products fabricated from high quality reinforced polyethylene (RPE). RPE liners offer a great many advantages over other types of geosynthetics for a wide variety of needs.
Handling and Installation
The inherent structural strength of RPE means that comparatively thinner sheets can produce the same or even better results than alternate materials like EPDM, PVC, and unreinforced polyethylene like HDPE and LDPE. RPE is typically half the thickness of most alternatives, including other types of polyethylene. Of course, thinner sheets mean the liners weigh less. In fact, RPE liners are as little as a third of the weight of similarly performing products. Thinner and lighter liners are easier to pack and less expensive to ship compared to their heavier, bulkier competitors. This can translate to significant savings in installation costs as well.
Relatively stiff liners like HDPE can not only be difficult to handle and install but are also particularly challenging when it comes to installing around corners and minimizing wrinkles. This is an important consideration because, over time, wrinkles and tight folds are susceptible to stress cracking, which can arise merely from prolonged steady pressure. This type of damage easily goes undetected and when left unrepaired, inevitably leads to containment failure.
Stiff materials also make it difficult to form good seams when the surface is uneven. Since some liner types are available only in relatively small panels, extensive on-site seaming may be required. Of course, this kind of additional challenge adds both expense and increases the risk of leaks from the outset.
RPE’s flexibility and light weight make it particularly easy to work with during these critical steps. Even in very large projects, RPE liners can often be fabricated as a single piece, all but eliminating the need for on-site seaming. In fact, BTL Liners can make the largest single liner panels in the industry. When seaming is required, it can be performed on-site in our 84,000 square foot, state of the art fabrication facility. BTL also offers custom fabricated liners, cut and welded to exact specifications.
Once your liner is selected and custom cut and fabricated, it is carefully packed, labeled, and shipped to your destination. Most liners can be moved and deployed onsite using manpower alone, without the need for heavy equipment. For problem-free installation, each individual roll or package includes helpful indicators for placement and direction of deployment.
Each of these characteristics, backed by BTL’s commitment to rapid turnaround make us an ideal partner, especially in emergency situations where fast installation and total containment are critical.
Outstanding Durability, Minimal Maintenance
Thanks to the reinforced construction of RPE, the final geomembrane product is inherently resistant to tears and punctures and is dimensionally stable. Using two (or more) different geomembrane types in the construction grants RPE the best characteristics of both worlds. HDPE conveys superior resistance to a wide range of chemicals, and good resistance to both Ozone and UV damage. The addition of LDPE makes the final product more flexible and pliable, so it’s easier to fold during installation and is better suited to handle uneven surfaces.
Impermeable RPE geomembrane products are the leader in composite geomembranes because of their outstanding durability:
- They rarely require underlayment when installed on well-prepared surfaces.
- Most of BTL’s RPE liners are certified for 20 years of service even in exposed applications.
- In applications where UV exposure is expected, optional coatings designed to increase UV resistance may be available on select products.
- They are designed to resist stretching and deformation even when under heavy loads.
- They tolerate even extremely cold temperatures well, making them much less likely to crack when exposed to stress.
Robust Resistance to Chemical Exposure
Polyethylene is basically an inert plastic and therefore inherently resistant to damage from exposure to strong acids and bases, as well as gentle oxidants and reducing agents. However, LDPE’s resistance, in general, is not quite as robust as HDPE under certain conditions. Some examples include acetic acid, fluorine, hexane, and mineral oil, particularly at higher temperatures.
The combination of LDPE and HDPE expands the material’s resistance, to include a wide range of acids, salt, and fertilizer nitrates. This is an important advantage since, over time, even minor degradation in vulnerable materials due to corrosion can destroy a liner’s integrity.
Safeguarding the Environment
Reinforced polyethylene liners are used in many applications where the focus is on protecting or even restoring the environment. Constructed wetlands, hazardous materials containment, and landfill daily covers are just a few examples. But the characteristics of the geomembrane itself offer some important advantages when you’re considering what material to use.
If you’re producing organic or hydroponic foods, it’s important to use the highest quality water possible to avoid the possibility of contaminating your product with E.coli or other illness-causing pathogens. However, not all geomembrane liners are considered safe for exposure to food or drinking water. BTL’s AquaArmor line of reinforced polyethylene products are all certified as NSF/ANSI 61, safe for potable (drinking) water. This certification indicates that no harmful chemicals or substances will leach from these liners into your water. This is an important quality, even when you’re not planning on drinking the water. Some liners have been shown to leach plasticizers (used to promote flexibility) into water over time, which are known to cause cancer and other long-term health effects. Whether you’re using liners to construct artificial wetlands, a prize koi pond, or in an aquaponics operation, any that leach dangerous chemicals into your water are incompatible.
Extensive Options
Reinforced polyethylene liners are inherently versatile, including the best features of both HDPE and LDPE, but are also available with a variety of valuable options that make them an exceptional fit for the most demanding applications.
Coatings
Texture is an important feature for geomembrane products since it determines how the material interacts with the materials it touches. Smooth membranes are easy to deploy but may tend to move over time, especially on steep slopes, with little to no friction underneath to stabilize them. They also won’t grip materials above them, which can make it difficult to keep elements like gravel, stones, and even aquatic plants in place when you’re maintaining a backyard pond.
In larger projects, where you’re seeking to control erosion by slowing and breaking up the rapid flow of water where there’s runoff, a textured surface is preferable to a smooth one. Even above ground, if you’re installing an exposed liner, a textured coating will help prevent material from shifting across the liner surface over time.
Coatings can also extend the life of RPE products, including coatings that provide exceptional UV and environmental resistance, making them suitable for exposed applications up to 20 years. Other coatings may be available for select products, depending on your supplier. Be sure to ask what your options are.
Layers
Once size does not fit all, especially when it comes to hard-working geomembranes. Relatively short term or lightweight containment jobs may be able to be adequately served by an inexpensive liner constructed with a single reinforcing woven HDPE layer sandwiched between two LDPE layers. Other more demanding applications require substantial strength, durability, longevity, and exceptional UV resistance. The ideal liner in this kind of situation will usually consist of several layers, including multiple layers for reinforcement and impermeability. These liners are necessarily thicker and heavier than simple 3-layer products, but still clock in at less than half the thickness and a third of the weight of many comparable competitors.
