Farming and animal husbandry LNG gasification station

Farming and animal husbandry LNG gasification station

Process flow:

The LNG is transported by the tank truck to the gasification station. The LNG unloading supercharger is used to increase the pressure inside the tank truck, and the LNG in the tank truck is sent to the LNG cryogenic storage tank for storage. When discharging from the LNG storage tank, the tank pressure is first increased by the self-pressurizing system of the storage tank, and then the liquid phase outlet valve of the storage tank is opened, and the LNG in the storage tank is sent to the gasifier through the pressure difference. It is sent to the municipal gas pipeline network through processes such as pressure regulation, metering and odor removal. When the outdoor ambient temperature is low and the natural gas temperature at the outlet of the air-temperature gasifier is lower than 5 °C, a water bath heater is connected in series at the outlet of the air-temperature gasifier to heat the gasified natural gas.

Equipment requirements:

The process characteristics of the 1LNG station are “low temperature storage and normal temperature use”. The design temperature of the tank reaches minus 196 degrees Celsius (the boiling point of LNG at normal temperature is minus 162 degrees Celsius), while the temperature of the outbound natural gas is not lower than the ambient temperature by 10 degrees Celsius.

The cryogenic storage tanks and cryogenic liquid pumps of the 2 stations are better in thermal insulation performance, and the cold preservation performance of valves and fittings is better.

The equipment, pipelines, instruments, valves and fittings in the low temperature zone of the 3LNG station have good operating performance under low temperature conditions, and have good mechanical strength, sealing and corrosion resistance.

4 Because the low-temperature liquid pump startup process is based on the inverter continuously increasing the speed to increase the power and increase the flow rate and provide high output pressure, the cryogenic liquid pump requires higher frequency and higher power, usually in a few seconds to ten seconds. Can meet the requirements, and the cold insulation performance is better.

5 Gasification equipment is required to be resistant to earthquakes, typhoon and meet design requirements under normal climatic conditions to achieve maximum gasification flow.

6 The manufacture and daily operation management of cryogenic storage tanks and filters have been incorporated into the national specifications for the manufacture, acceptance and inspection of pressure vessels; gasifiers and low-temperature hydrocarbon pumps are not regulated in the country in the process of manufacture. To carry out relevant US industry standards, the location of welding, renovating, repairing or moving the pressure vessel on the pressure vessel body must be reported to the inspection unit of the pressure vessel.

Site selection and general layout of LNG gasification station:

1 LNG gasification station site selection

The location of the gasification station is closely related to its safety. Therefore, the gasification station should be arranged in a place with convenient transportation and people's intensive places. The fire separation distance from the surrounding buildings must comply with the provisions of the Code for Urban Gas Design GB 50028-2006. And consider the natural gas pipeline network that is easy to access to towns, and reserve enough space for long-term development.

2 LNG gasification station general plan layout

Reasonably arranging the buildings and process facilities in the gasification station can make the entire gasification station safe, economical and beautiful. The general plane of the station area should be divided into sections, that is, divided into production areas (including unloading, storage, gasification, pressure regulation and other process areas) and auxiliary areas. The production area is arranged on the upwind side or upper side wind of the lowest frequency wind direction in the station area. On the side, the fire separation distance of the built-in structures must meet the requirements of the “Code for Design of Urban Gases” GB 50028-2006.