Fog Cloud Formation And Processing Research Near LNG Vaporizer

With the energy structure transformation, nature gas consumption was increasedcontinuously and LNG peak-shaving station was increased year by year for solvingpeak-shaving question of season or day. Air-heating finned-tube vaporizer that is structuralsimple, cheap and without additional heating source is used by corresponding surportingequipment to gasification, but people often ignore the point that the original environment wasdestroied by releasing cold energy of LNG gasification. Air that absorbed cold energy willform fog cloud. If fog cloud does not promptly deal with, affected the personal safety of theoperator and nearby residents, reduced the visibility of roads, destroyed the city’s landscape,resulting in humidity rises in downdind, destroying the ecological balance of the surroundingenvironment, and causing other issues.For question of fog cloud on LNG peak shaving station, this paper conducted a detailedresearch, starting from formation mechanism of fog cloud, flow state and influencing factorsof fog cloud, and treatment of fog cloud.Based on thermodynamics theory, condesation in moist air was expouded, and reducingthe air temperature or increasing the partial pressure of water vapor condesation will occur.The nucleation factors of ice crystal was analysed by nucleation theory. Air was easier tocondense into ice crystals to form fog cloud, when air contained more dust.Meanwhile, the physical modal of fog cloud flow was established, and fog cloud wassimulated by CFD technology. Reason and distribution range of fog cloud formation wasfurther revealed, and factors were comparatively analysed. The research found that surfacetemperature of air-heating finned-tube vaporizer, wind speed and direction are main factors,and influence of the ambient temperature is very little when compared to other factors. Theeffect of side inlet air is better than top inlet air when no taking into account other issues suchan installation place.For the work requirement of fog cloud processing system, this paper designed a set offog cloud processing system which included the main circuit system, circuit control sytem,and so on. The closed-loop control mode was adopted to deal with, preventing ventilatoridling, causing a large waste of energy. Simultaneously, VVVF principle and fan controlpriciple were analysed, and system hardware such as temperature sensor, PLC, inverter, fan, and so on were choosed.