Safety protection measures for natural gas storage tanks

Liquefied Natural Gas (LNG), whose main component is methane, is recognized as the cleanest fossil energy on the planet. Colorless, odorless, non-toxic and non-corrosive. The manufacturing process is to first purify the natural gas produced in the gas field, and after a series of ultra-low temperature liquefaction, it is transported by LNG ship. Liquefied natural gas has very little air pollution after combustion, and it emits a large amount of heat, so liquefied natural gas is a relatively advanced energy source. When storing natural gas storage tanks, it is necessary to pay attention to effective protection of the storage tanks to extend the service life of the LNG storage tanks.
 
Protective measures for natural gas storage tanks:
1. Nitrogen seals shall be provided between the inner and outer tank interlayers of the LNG storage tank to maintain the positive pressure state of the interlayer (less than 0.5kPa) to avoid the entry of humid air and ensure the good thermal insulation performance of pearlescent sand.
 
2. The internal tank of the LNG storage tank shall be equipped with a double set of liquid level alarm interlocking system. When the liquid level of the internal tank of the LNG storage tank is higher than the set value, a high liquid level alarm is activated, and when the high liquid level is reached, it is started Interlocking system to shut off the valve on the inlet pipe of the LNG storage tank. When the liquid level of the LNG storage tank in the inner tank is lower than the set value, a low liquid level alarm is activated. When the low liquid level is reached, the interlock system is activated to cut off the valve on the liquid discharge pipe of the LNG storage tank and close the loading pump. . 3. The internal tank of the Liquefied Natural Gas storage tank is equipped with two sets of pressure monitoring and alarm interlocking systems. When the internal tank LNG storage tank pressure is higher than the set value, a high pressure alarm is activated, the interlocking system is activated, and the increase of the LNG storage tank is cut off. Press the automatic valve on the system piping to stop boosting. When the internal tank LNG storage tank pressure is lower than the set value, a low pressure alarm is activated, and the backflow regulating valve at the outlet of the BOG compressor is opened to ensure that the internal tank pressure of the LNG storage tank must not form a negative pressure. When the low pressure is reached, the interlock system is activated, the automatic valve on the pipeline of the LNG storage tank pressurization system is opened, and the vaporized part of the Liquefied Natural Gas storage tank is pressurized for the inner tank.
 
4. The inner tank of the storage tank is equipped with a complete safety system-double sets of safety valves and double sets of breathing valves, and is switched by a three-way valve. When the inner tank pressure exceeds 25kPa, the safety valve takes off and releases pressure; when the inner tank pressure is lower than -0.5kPa, the breathing valve opens and air enters the inner tank to ensure that equipment damage and personal injury are avoided. The top of the outer tank is provided with double sets of safety valves and double sets of breathing valves to ensure that the interlayer pressure is within a certain range and the safety of the equipment.