High-Efficiency Application and Core Advantages of Geomembranes in Large Water Tanks and Salt Ponds

In water conservancy projects and salt production, seepage prevention performance is a core factor determining the stability, economic benefits, and environmental compliance of facilities. With the iteration of material technology, geomembranes, especially high-density polyethylene (HDPE) geomembranes, have gradually replaced traditional seepage prevention materials due to their superior seepage prevention, corrosion resistance, and aging resistance. They have become the preferred solution for the construction and renovation of large water tanks and salt ponds, and are widely used in reservoirs, water storage ponds, sewage treatment plants, salt fields, and other scenarios, achieving a dual improvement in project quality and comprehensive benefits.

I. Core Performance Support of Geomembranes: The Material Basis for Adapting to Complex Scenarios

Geomembranes are high-molecular seepage prevention materials made from polyethylene as the core raw material. Among them, HDPE geomembranes have become the mainstream choice for large-scale projects due to their structural stability and environmental adaptability. Its core performance advantages can be summarized as follows, precisely matching the stringent requirements of large water tanks and brine ponds:

- Extreme seepage prevention: The HDPE geomembrane has a permeability coefficient as low as 10⁻¹³ cm/s, far exceeding traditional clay impermeable layers (10⁻⁷ cm/s) and sodium bentonite membranes, creating a near-seamless seepage barrier that blocks liquid leakage at its source.

- Superior environmental resistance: Manufactured using a three-layer co-extrusion process, the HDPE geomembrane boasts a density exceeding 0.94 g/cm³, a tensile strength exceeding 27 MPa, and an elongation at break ≥700%. It maintains stable performance in extreme temperature environments ranging from -60℃ to +80℃. It also exhibits excellent chemical corrosion resistance, resisting erosion from high-concentration salt water and sewage. Its UV resistance and aging resistance are outstanding, with a normal service life exceeding 30 years. Some high-temperature resistant formulations can withstand continuous high temperatures of 100℃.

- Excellent Construction and Adaptability: Geomembranes can be up to 8 meters wide and can be flexibly cut to fit various terrains. Seamless connections are achieved through hot-melt welding, with joint strength exceeding 90% of the parent material. This allows for easy adaptation to irregular foundations and complex terrains in large water tanks and salt ponds. Construction is convenient and efficient, requiring no comple

x procedures and significantly shortening the construction period.

- Environmental Protection: HDPE geomembranes use an environmentally friendly formula, are non-toxic and harmless, and will not release harmful substances into water bodies. They are suitable for drinking water tanks, food-grade salt ponds, and other similar applications.

II. Applications in Large Water Tanks: Water Conservation, Quality Stabilization, and Safety Assurance

The core requirements for seepage prevention in large water tanks (including reservoirs, water storage tanks, sewage treatment ponds, artificial lakes, etc.) are to reduce water resource loss, prevent water pollution, and ensure structural stability. Geomembranes demonstrate irreplaceable value in these scenarios.

In water conservancy and water storage projects, traditional clay seepage prevention layers suffer from difficulties in construction, precise control of compaction, and high leakage rates. Using HDPE geomembrane can improve seepage prevention efficiency by more than 100 times compared to traditional clay.

In wastewater treatment ponds, industrial water storage tanks, and other applications, geomembranes effectively block the penetration of corrosive media such as acids, alkalis, and organic pollutants, protecting the surrounding soil and groundwater environment. Simultaneously, their puncture resistance and tensile strength can withstand uneven settlement of the tank foundation, preventing the seepage prevention layer from cracking and reducing the risk of future maintenance. For drinking water storage tanks, the environmentally friendly GH-2S HDPE geomembrane complies with the national standard GB/T17643-2011, with carbon black content controlled at 2.0%-3.0%, and a performance retention rate of ≥50% after 1600 hours of UV exposure, ensuring water quality safety and long-term seepage prevention.

III. Applications in Salt Ponds: Increased Production, Environmental Protection, and Extended Lifespan

Salt ponds (including sea salt production areas, brine ponds, and potash mine brine ponds) operate in environments characterized by high salt corrosion, strong ultraviolet radiation, and large diurnal temperature variations, placing stringent demands on the corrosion resistance and stability of geomembranes. Modified HDPE geomembranes specifically address these challenges, becoming a core supporting material for salt production.

In traditional salt production areas, brine leakage not only leads to decreased salt yield but also causes soil salinization in the surrounding area, damaging the ecological environment. Using modified HDPE geomembranes for salt ponds improves salt and alkali resistance by 30%, allowing for long-term stable use in 30% saline environments. Data from a large salt field shows that after laying a 2.0mm thick specialized geomembrane, the lifespan of the salt pond increased from 5 years to 12 years, annual maintenance costs decreased by 60%, and salt production increased by more than 15%. This improvement stems from two aspects: first, the geomembrane's photothermal absorption properties accelerate water evaporation and promote salt crystallization; second, the impermeable barrier reduces brine loss while preventing impurities from entering, thus improving salt purity and selling price.

In extreme environment brine projects, the adaptability of geomembranes is even more pronounced. In the Saskatchewan potash mine brine project in Canada, it was necessary to cope with the alternating effects of high-temperature brine (83°C) and low-temperature climates (below -20°C), while resisting erosion from media such as diesel fuel and distillates. Using a high-temperature resistant HDPE geomembrane, the nearly 700,000 square feet of lining system operated stably, and welding could be successfully carried out even in the low-temperature winter conditions, ensuring continuous production in solution mining.

IV. Comparison of Mainstream Seepage Control Solutions: The Comprehensive Advantages of Geomembranes are Prominent

Currently, there are three main seepage control solutions for large water tanks and salt ponds. A technical and economic comparison clearly demonstrates the advantages of geomembranes:

1. Manually Compacted Clay Seepage Control: While achieving the required permeability coefficient, construction is difficult, requiring extremely high clay quality and compaction. The unit cost is 80-90 RMB/㎡, and it is easily affected by terrain, with uncontrollable leakage risks. It has been gradually phased out.

2.  Sodium Bentonite Rolls: Relying on water-swellable self-healing properties, the cost is 40-50 RMB/㎡. However, it has low tensile strength, poor aging resistance, and construction is greatly affected by weather. Its stability in the highly corrosive environment of salt ponds is insufficient.

3. HDPE Geomembrane: With an extremely low permeability coefficient, reliable seepage control effect, and a unit cost of around 50 RMB/㎡, it combines advantages such as corrosion resistance, aging resistance, and convenient construction. Its service life can reach 30-50 years, making it the top choice in terms of overall cost-effectiveness and adaptability.

   
   

V. Application Outlook: Geomembrane Technology Upgrades Empower Green Engineering

With increasingly stringent environmental policies and higher engineering quality standards, the application of geomembranes in large water tanks and salt ponds will become more refined. On the one hand, the promotion of composite geomembranes (a combination of geomembrane and geotextile) will further enhance their dual functions of seepage prevention and reinforcement, adapting to complex scenarios such as dams and slopes. On the other hand, customized formulas (such as high-temperature resistant and ultra-thick types) will meet the personalized needs of special salt ponds and industrial wastewater ponds.

In the future, geomembranes will not only be a core choice for seepage prevention materials, but will also become a key support for water conservancy, salt industry, and environmental protection projects to achieve the goals of "water conservation and energy saving, ecological protection, cost reduction and efficiency improvement," driving the industry towards green and efficient upgrading.