With the rapid growth of the global economy and the expansion of energy demand, all countries have the operating activities of LPG, and the LPG supply range is very large. But in comparison, liquefied natural gas can be transported efficiently on roads, railways and ships; It is widely used, it can be used as vehicle fuel, power generation fuel, civil and industrial fuel, chemical raw materials; The features of low investment, quick results and flexibility of air supply facilities. Undoubtedly, the development of the world LNG industry provides a good opportunity.
Although China is a resource-rich countries, but as a result of domestic natural gas resources are limited, then a strategic point of consideration, makes the development of LNG import project, the construction of LNG small stand to make up for the shortage of natural gas has become the focus of the current domestic city gas industry relatively.
Liquefied Natural Gas (LNG, Liquefied Natural Gas) is another form of energy that is transformed by Natural Gas. Since methane is more than LNG 96%, it is essentially similar to liquid methane. The atmospheric pressure boiling point of LNG is - 162 ℃, liquid density of 430 kg/m3, latent heat of vaporization is 510.25 kJ/m3. The atmospheric pressure density is 0.688 kg/m3, and the air mixing can form an explosive mixture. The explosion limit is 3.6% ~ 6.5% and the explosion limit is 13% ~ 17%.
The production medium in the small station of LNG is mainly natural gas, liquefied natural gas, etc. If not handled properly, there are all kinds of accidents such as fire and explosion. From the characteristics of the production medium, the main points are as follows:
1. In some LNG equipment, due to the stratification of its components and density differences, the LNG suddenly evaporates and the pressure rises sharply. If the pressure exceeds the limit pressure capacity of the equipment, the equipment can be damaged and dangerous media leakage, even explosion.
2. LNG is stored and operated at a low temperature. Therefore, once the leakage occurs, the low temperature can cause the material performance to decrease, causing more serious accidents and causing serious injury to the human body.
3. Although natural gas is less toxic, it usually contains 82% ~ 98% of the methane. Once a leak, the oxygen in the air will be reduced, resulting in the human injury such as human injury and death.
4. Air - gas mixture explosion limits are very narrow. If there is an external source of fire (Mars, flame, etc.), it is easy to burn and even explode. At the same time, the thermal radiation produced by the combustion of gas can cause great harm to the human body and device. At the same time, the thermal radiation produced by the combustion of gas can cause great harm to the human body and device.
As you can see, for LNG systems, safety is of Paramount importance. During the design process, hazard analysis and assessment must be made to determine the risks associated with LNG installations. In accordance with the relevant standards and operation management experience, design a comprehensive control, the safety of the small station to reduce the risk of loss of the personal and property, and let the whole device to achieve a high level of security.