CNG storage vessel

The storage vessels of the CNG package (Basket) consists of a set of natural gas storage cylinders that are placed in a pre-designed structure. These cylinders are connected by a tubing system and a set of connectors and manifolds.

According to the capacity of the CNG compressor, the number of baskets varies. (Generally, a 24 vessel package is considered for each 500 Nm3/hr). In a CNG package, the moisture content of the inlet gas is removed by a gas dryer, then the dry gas is compressed by a reciprocating compressor and at the end the pressurized gas is stored in the baskets. The baskets are connected to the refueling dispensers and prevent the pressure drop during the refueling of the cars.

Specifications of gas storage vessels

• Vessels are manufactured cylindrical with seamless tubes by complex forming processes.
• The storage vessels are divided into three modes: low, medium and high pressure. They gradually enhances the pressure of the car’s fuel tank to the desired value during refueling, so that the imposed loads on the compressor reach to their minimum value.
• Baskets are manufactured and placed in maximum 27 cylinders in one structure. The number of cylinders can be reduced or increased according to the customer’s needs.
• The material used in making the cylinders is chromium molybdenum steel.
• The maximum working pressure of the cylinders is 275 bar.
• The capacity of the cylinders is 80 liters.
• As the cylinders operate at high pressures, in order to increase safety and prevent destructive phenomenon, PSVs protect vessel over pressurization which caused by gas temperature enhancement. On the other hand, the safety valves of the manifolds also prevent the package pressure from reaching the prohibited value.

It should be noted that HAVAYAR industrial group has the ability of manufacturing a set of pressurized storage vessels in different design pressures and quantities declared by the customer in the form of a skid (Basket) which can be utilized for other gases storage such as nitrogen.