One typical storage solution for liquefied propane (LPG) is bimetal full containment storage tank. The storage system consists of a primary tank (inner tank), a secondary tank (outer tank), both made of A537CL2 steel, and piping system made of carbon steel, in compliance with GB/T 8163-2018 and GB/T 12459-2017.
The storage system is further divided into subsystems of inlet system, purge system, outlet system, pump BOG backflow system, BOG recovery system, pressurization system, EAG flare system and safety control system.
Pressure safety controls. (1) When the inner tank pressure is rising to 10-13 kPa, the cryogenic pressure regulating valve will be switched on automatically to reduce the pressure by discharging the gas to BOG recuperator or low pressure flare. (2) When the inner tank pressure is dropping to 2 kPa, the pressurization system will be activated by letting in nitrogen until the pressure reaches 5 kPa. (3) When the inner tank pressure rises up to 17 kPa, the pressure relief valve (PRV) will be switched on, and when the pressure drops to -0.22 kPa, the vacuum relief valve (VRV) will be switched on. Two sets of PRV (one standby) and three sets of VRV (one standby) are equipped.
Four sets of pressure transmitters are installed for pressure monitoring, sending 4-20 mA signals to DCS and SIS system, also equipped with field display.
Two sets of servo level gauges and one set of radar level gauge are installed and interlocked.
For temperature monitoring, one set of multispot thermometer is attached to the inner tank shell and the floor, installed inside a stainless steel conduit of 6 mm diameter, filled with MgO. One set of average thermometer is installed to measure the stored liquid temperature. Thermometers are also installed on pressure relief / venting pipings. The integrated temperature monitoring on different locations ensures uniform cooling during pre-cooling and consolidated safety during daily operation.
As a professional one-stop-shop industrial gas solution providers, DOER is becoming widely known for bimetal / steel atmospheric cryogenic full / single containment storage tanks for LNG receiving terminals, reserve centers & peak shaving stations, and also VPSA oxygen plant for boilers, smelters. Focusing on innovation & improvements, DOER always values the customer-driven quality and long term partnership. Contact us now if you're interested in any type of cooperation.