January 29, 2018
1.LNG Technological Principle
Liquefied natural gas (LNG) is usually transported by tank car and stored in low temperature storage tank. The LNG is filled in tank car at LNG storage and distribution station, transported to LNG gasification station, and then filled into low temperature storage tank through unloading pressurized Skid (or tank car self-pressurizing system). While the system is working, through tank supercharger (or Skid), the LNG in the cryogenic tank is gasified into the main gasifier and heated to gaseous natural gas (if the ambient temperature is too low, the water bath electric heater is needed to reheat it till the calibration temperature is reached), and then after filtration, pressure regulation, metering and odorization, it enter to the downstream main gas pipeline (the aforementioned components are selected according to the flowchart) and then to each gas point separately.
A small amount of natural gas produced by the system is recovered or released according to the requirement. The recovered gas is heated by BOG heater and then enjoined into the main pipeline. The released gas is collected to the releasing tower for discharge treatment (the low temperature gas must be heated by EAG heater).
The main equipment of LNG gasification station includes low temperature storage tank, tank supercharger (Skid), stainless steel hose, unloading pressurized skid, gasifier (skid), pressure-regulating metering skid (name changed according to selected components), instrument air system, releasing system, instrumentation, gas alarm device and valve fittings, pressure and temperature field display (or remote display), control system (simple or high match according to the user), etc.. All instrument wiring is summarized to explosion proof junction box. The signal of the whole gasification station can be centralized controlled and transmitted to the PLC master control room to monitor the operation of the gasification station in real time.

2. Advantages of Changyi LNG Structure
Traditional LNG station consists of low temperature storage tank, unloading supercharger, storage tank supercharger, BOG gasifier, main gasifier, EAG gasifier , reheater, pressure regulation and metering area, electrical control system, high and low temperature pipeline accessories and system, lightning protection system, Fire control system and other major components.  
Advantages and disadvantages of traditional station yard
1.All the equipment is installed and made at site, and can be controlled in real time according to the specific position of the site. Many specific designs are saved.
2.It is difficult to control the quality of all the process pipes and pipe accessories made at site. For example, the welding seam inspection is difficult conduct at site where it is necessary to be sealed; the process valve is not welded; the field appearance treatment is not qualified, and so on;
3.The field manufacture is generally carried out by the engineering company.  The LNG station is cross-professional, and it is difficult to control the whole design, which leads to various kinds of adjustment in the later stage, and the construction period and the adjustment time are longer and the project cost is higher
Our company LNG Skid contains all of the above equipment and has many years practical experience in the highly LNG Skid. The advantages are as follows:
1.The whole station is divided into several blocks, the storage tank skid, the tank pressurized skid, BOG skid, EAG skid, unloading pressurized skid, gasification heating and regulating pressure metering comprehensive skid. Each skid is successfully debugged in the factory. There is no need to debug at field.
2.All the valves and pipes accessories are concentrated on the skid. Each skid contains the valves and the skid frame, leaving inlet and outlet flange for connecting with outside. The structure of each skid is highly integrated so that its length and width are controlled within the range that can be transported;
3.After arriving at site, the equipment can be put into place while the equipment is unloaded; after that, the rest of the work is the pipe connection between the skid and the skid. The working at the site is simplified and the construction time is highly concentrated;

The following image shows the 2000Nm³/H skid gasification station designed and manufactured by our company for Conway Chemical Fiber Group.