LNG bottle group type gas supply patterns as emerging, with less investment, small occupied area, fast production, high safety, in recent years, more and more gas users and enterprises, its equipment and technology also gradually development and innovation, the LNG point for a brief introduction:

First, basic situation

Flow allocation according to gas consumption of 100Nm3/h.

Two, equipment selection

The equipment in LNG bottle group is divided into four parts: gas cylinder, carburetor, regulator, flowmeter, and other equipment such as odorant and heat exchanger can be installed according to the needs of users. In the selection of equipment of LNG at the early stage of the project, not only to meet the demand for gas, but also consider reducing the cost of equipment and days after operation and maintenance costs. Following equipment:

Gas cylinder: according to the user gas volume, select 8 DPL-195 liquefied natural gas cylinder, 4 with 4 preparation, to ensure the replacement or filling, uninterrupted gas supply.

Carburetor carburetor: frost due to long time operation, and effect of gasification efficiency, carburetor adopt dual 75m3/h specifications, with a preparation, in the main road frost is not used, the standby vaporizer, guarantee gas supply.

Pressure regulator: LNG liquid in the cylinder after vaporization, the pressure is higher, take a single road two stage pressure adjustment, so that the pressure to normal use pressure.

Flow meter: common diaphragm gas meter can meet the measurement needs, if in relatively remote areas, you can choose to install the remote function, provide gas liquid pressure, outlet pressure, cylinder pressure and other parameters were used and the leakage alarm, convenient management. If the user has a large amount of gas in winter, the flowmeter with temperature and pressure compensation function can also be considered to ensure the accuracy of the measurement.

Three. Process flow

Four 、 LNG bottle group station construction

LNG bottle group "town gas station construction should comply with the design specifications", "petroleum and natural gas engineering design code for fire protection" and other relevant laws and regulations, points for the station should be far away from crowded areas, and isolation measures, at the same time, due to the presence of the BOG gas station ventilation requirements, good lightning protection standards the ground facilities, so as to ensure the safety of gas station. According to the characteristics of LNG at low temperature, the equipment, piping, instruments, valves and all kinds of fittings in the station require better operating performance at low temperature, and have good mechanical strength, sealing and corrosion resistance.

Five 、 LNG gas cylinder equipment operation regulation

Remove LNG cryogenic bottle

1. Disassembly process of connecting valve

(1) turn off the booster valve, air valve and manifold low temperature stop valve in turn.

(2) use the explosion proof tools to remove the cryogenic bottle connection pipe slowly, and the hose joint should be properly protected to prevent damage to the hose joint or to enter impurities in the hose.

2. Connect the inlet and outlet valve disassembly process

(1) turn off valve, pipe and a liquid cryogenic valves, wait for about 3 minutes, the liquid inside the tube to prevent spills skin frostbite gasification.

(2) use the explosion proof tools to remove the cryogenic bottle connection pipe slowly, and the hose joint should be properly protected to prevent damage to the hose joint or to enter impurities in the hose.

3, filling LNG low temperature bottle

(1) ready, connect the pneumatic pipe, open the vent valve, inlet and outlet valve in turn.

(2) in the filling process, according to the liquid injection machine to display the liquid flow control the size of the vent valve switch until the filling is completed.  No overload.

(3) after filling, turn off the vent valve, the inlet and outlet valve in turn, and then unload the hose when it is vaporized for a period of time (remove the hose slowly, prevent the liquid splashing and frostbite the skin).

(4) leak detector detects the leakage of LNG cryogenic bottles at each valve port.

4, connect LNG cryogenic bottle group

Gas supply for connection valve:

(1) connect the hose with the air valve, turn on the valve, manifold, low temperature cut-off valve, carburetor double inlet valve in turn.

(2) leak detector detects whether there is air leakage at the hose connection.

Connect the inlet and outlet valves to supply gas:

(1) after the hose is connected to the inlet and outlet valves, the inlet and outlet valves, the manifold low temperature stop valves and the carburetor inlet valves (the other one) are sequentially opened.

(2) leak detector detects whether there is air leakage at the hose connection.

5. Matters needing attention during transportation

(1) in the process of handling and filling of low temperature bottle, the bottle body must be kept upright, and it is strictly prohibited to be put down.

(2) the transportation vehicle, low temperature applications such as bandages bottle anti-static rope bottle are bundled and tied up, no fixed bottle using metal chain.

Six 、 LNG bottle group station safety analysis and emergency disposal

Compared to the gas pipeline gas and liquefied petroleum gas, LNG due to its own characteristics, high ignition point, difficult to be ignited, and the vaporized density is low, easy to accidentally leak after dilution and dispersion, thereby reducing the possibility of explosion, so LNG security is better than other types of gas.