Double membrane gas holder

The outer membrane air intake blower maintains constant pressure. When the amount of biogas in the inner membrane decreases, the outer membrane is inhaled through the blower to maintain the design pressure of the inner membrane biogas. When the amount of biogas increases, the inner membrane stretches normally and the excess air in the outer membrane is discharged through the safety valve, so that the biogas pressure is always constant at the required design pressure. The insulation principle of the adjustable membrane biogas storage cabinet: filling air between the inner and outer membranes can effectively prevent the entry of cold air from the outside.

The equipment has the characteristics of light structure, quick installation, corrosion resistance and long service life. It is widely used in biogas projects, landfill gas collection, sewage treatment plants and other places.

Introduction of double membrane gas holder membrane materials 

Inner membrane (main gas storage membrane): Made of PVDF membrane, it comes into direct contact with biogas and offers excellent airtightness and corrosion resistance.

Outer membrane (protective membrane): Protects the inner membrane from external environmental influences such as UV rays, wind and rain, while also being inflated by a fan to maintain a stable shape.

Base membrane: Made of PVC membrane, it offers leak-proof properties and excellent airtightness.

Base ring and sealing system: Ensures a sealed connection between the gas tank and the concrete foundation.

Advantages of double membrane gas holder

Compared with traditional wet gasholders (such as water tank type) and dry gasholders (such as membrane sealed type and dual-mode dry gasholders), double membrane gasholders have significant advantages in investment cost, construction period, operation and maintenance, and adaptability, which are specifically reflected in the following aspects:

1, Low investment cost and extremely short construction period
Traditional steel gasholders require a large amount of steel, resulting in high material and processing costs. They also require large foundations and specialized hoisting, with construction periods often lasting 1-2 months. Double-membrane gasholders are constructed using flexible membranes, significantly reducing material costs. Modular prefabrication requires only foundation leveling and assembly on site, eliminating the need for large machinery. Construction periods can be shortened to 7-15 days, significantly reducing initial investment and installation costs.

2, Excellent corrosion resistance and long service life
H₂S and water vapor in biogas environments are highly corrosive to steel, requiring regular, expensive anti-corrosion maintenance for traditional steel cabinets. The double-membrane gas cabinet's inner membrane utilizes a specialized coating designed to resist H₂S and biogas corrosion, while the outer membrane is UV-resistant and aging-resistant, resulting in a strong resistance to chemical corrosion and weathering. No metal parts in the entire system come into contact with biogas, fundamentally eliminating the corrosion problem. The system is designed to have a service life of up to 15 years, with no anti-corrosion maintenance required.

3, Stable operating pressure and high degree of automation
The double-membrane gas holder automatically adjusts the pressure of the buffer air between the inner and outer membranes through an intelligent control system, thereby achieving the rise and fall of the inner membrane of the gas holder and ensuring a highly stable biogas output pressure. This constant pressure output provides stable operating conditions for subsequent desulfurization equipment, boosters or generator sets, which is conducive to the smooth and efficient operation of the entire system. The system is equipped with pressure sensors and PLC controllers, which can realize unmanned, automatic operation and remote monitoring.

4, Very low maintenance cost and easy operation
Traditional gasholders require regular cleaning of water seal tank sludge, replacement of sealing oil, or overhaul of complex piston systems, which results in heavy maintenance and high costs. Double-membrane gasholders have no transmission parts and no sealing fluids. Daily maintenance only requires regular inspection of the fan operating status and cabinet appearance. The maintenance cost is less than 30% of that of traditional gasholders. The position of the inner membrane is visible, and the gas volume is clear at a glance, making it easy for operators to intuitively understand the system status.

5, High safety and reliability
Traditional low-pressure wet gasholders have the risk of icing, while dry gasholders may have the risk of piston tilting and seal failure. Double-membrane gasholders have a low working pressure and are micro-pressure vessels, which do not need to be inspected as pressure vessels. They are equipped with overpressure protection valves, negative pressure preventers and emergency exhaust devices. Multiple safety measures ensure that the equipment can safely release pressure in various abnormal situations without explosion risks.

6, Strong adaptability and flexible application
Double-membrane gas cabinets have low foundation requirements and can adapt to small uneven settlements. Their light weight makes them particularly suitable for sites with soft soil foundations, tidal flats, and mountainous areas that are not suitable for heavy steel cabinets. They offer a wide range of capacities and can be flexibly customized according to project requirements. They are very suitable for large, medium, and small biogas projects, as well as temporary storage and buffering of waste gas in landfills, sewage treatment plants, and other locations.。

Applicable Scenarios

1, Small projects (e.g., livestock farms, small sewage treatment plants): Recommended volume: 100-500 m³, operating pressure: 4-6 kPa.

2, Medium-sized projects (e.g., regional landfills, industrial biogas projects): Recommended volume: 500-2,000 m³, operating pressure: 5-8 kPa.

3, Large projects (e.g., municipal sludge treatment, large-scale biogas projects): Recommended volume: 2,000 m³ or more, operating pressure: 0.5-2 kPa.