Low-pressure wet gas storage tanks, which are variable-volume metal cabinets, consist mainly of a water sump, a bell cover, a tower section, and an ascending and descending guide mechanism. When biogas is introduced into the storage tank, the bell cover and tower section inside the water sump rise sequentially (from smallest to largest in diameter). When biogas is extracted from the tank, the tower section and bell cover descend sequentially (from largest to smallest in diameter) back into the water sump. The interior of the bell cover and tower section, as well as between the interior tower section and the exterior tower section, are sealed with water to isolate the biogas inside the tank from the atmosphere. Therefore, as the tower sections rise and fall, the storage volume and pressure of the biogas change accordingly.
Low-pressure wet gas storage tanks feature simplicity in structure, ease of construction, and reliable operation and sealing. For small-capacity storage tanks, using wet gas tanks is more economical.
The characteristics of the low-pressure wet gas storage tank are as follows:
1. Since sinks are not required, the base load and costs can be significantly reduced.
2. Small land area, reduced steel consumption.
3. The snow load is supported by the gas cylinder, not directly affecting the piston, thus the gas pressure is unaffected by the snow.
4. The gas storage for fuel can maintain a dry condition.
5. Uneven settlement is easily remedied at the foundation level.
6. The sealing liquid can be used at temperatures as low as -30°C, so no concern is needed for water seal freezing in cold regions.
7. The gas storage pressure is generally stable, with an average pressure of 1590-2000Pa, and fluctuations do not exceed 100-150Pa.
Steel Wet Gas Storage Vessels in High Demand in Cities: Jilin, Liaoning, Heilongjiang, Hunan, Hubei