Process flow of low-temperature LNG storage tank

Process flow of low-temperature Lng Storage Tank - Doer Equipment

The LNG from the external system enters the LNG Storage Tank and is stored after flashing of the LNG product (-161.2C, 18kPa). The flashing gas phase enters the BOG main and is sent

outside the boundary.

To reduce the risk of stratification of LNG in the storage tank, LNG enters the tank in two ways: one is feeding from the top, and the other is feeding from the bottom through an internal insertion pipe.

Both the top and bottom inlet pipelines are equipped with remotely controllable control valves. An emergency shut-off valve is installed on the inlet main pipe, which is interlocked with the liquid level and pressure to prevent overpressure and overflow of the storage tank.

Additionally, a top inlet pre cooling pipeline is installed, and a spiral spray device is installed below the suspended ceiling of the inner tank to ensure uniform cooling of the inner tank and avoid excessive local temperature difference stress. The daily LNG submersible pump circulates the LNG inside the tank to prevent stratification and rolling of the LNG inside the tank.

The LNG in the storage tank is transported to the loading system through a submerged pump (one for backup and one for use).