SEARCH
Based on China's economic development situation and the general trend of energy structure optimization and adjustment, LNG is becoming increasingly important in the energy consumption structure due to its convenient storage and transportation, clean and environmental protection, flexibility, safety and reliability. With the continuous advancement of the reform of the energy structure, the demand for LNG is growing rapidly. In the future, the scale of LNG receiving stations is gradually moving towards large reserve bases, which can ensure the safety of gas supply through LNG reserves.
Based on the analysis of the processing scale and functions planned for the large LNG reserve base, combined with the layout experience of the general drawing of LNG receiving station, this paper comprehensively considers the one-time planning and step-by-step implementation, reasonably plans the layout of LNG storage tank groups and related process facilities, so as to smooth the process and facilitate the construction of planning reserved areas. We should not only reduce initial investment in construction, but also reserve sufficient space for subsequent development.
Utility area and auxiliary production area
This area is arranged independently from the process plant area, including the main substation, control room, emergency generator room, air pressed nitrogen, production and living water pump room, sewage treatment device, maintenance workshop and comprehensive warehouse. The air compressed nitrogen device should be close to the main load center and arranged according to the wind direction and spacing required by the specification. The main substation should be arranged according to the external power inlet line line near the edge of the plant, which is convenient for the inlet and outlet lines. If the plant is large, the substation should be located in the storage tank group area, process equipment area and other facility areas. The control room should be arranged relatively close to the production area and the cable length should be shortened for easy operation.
In order to facilitate management during production operation, the maintenance workshop and comprehensive warehouse are arranged outside the production area to reduce the issuance of unnecessary work permit.
Tank truck loading area, LNG tank filling area
The area should be located at the edge of the factory and become an independent area. Special entrances and exits should be set up. If the tank truck loading capacity is large, entrances and exits should be set up separately, and two loadometer should be set up respectively. The ticket booth can be set up at the exit entrance to shorten the time of ticket issuing and make it convenient to enter and exit quickly. This area is relatively isolated from the factory with solid walls, and there should be enough space in the area to make the tanker move and turn as little as possible. If the amount of loading is large, an independent security waiting area can be set up near the loading area. Before loading, the tank truck can complete the security check and stay in this area for a short time. The driver's lounge and electronic number calling system can be set up in this area to facilitate the tank truck loading and entering the factory scheduling management. In order to save land, the loading pry can be arranged in the form of an island double pry. If the amount of LNG tank filling is large, in order to avoid the interference to the LNG tanker, the tank filling can be arranged independently into areas, and a certain tank stacking site is set up.
Railway tank car filling area
LNG rail transportation is not affected by rain and snow, and can carry out long-distance bulk transportation. With the large volume, fast transportation speed and low cost, with the development of industrial policies and the continuous advancement of LNG rail transportation system, if LNG rail tank cars are operated in the next few years, it is bound to bring the reform of LNG transportation mode. In the planning of large-scale LNG reserve base, the filling area of railway tank cars can be reserved according to market conditions and base positioning. Once conditions are mature, it can be put into use quickly and seize the market opportunity.
Master plan and layout
The planning and layout of large-scale LNG reserve base mainly consider rationality, implemensibility and safety. In terms of safety, fire spacing and layout requirements should be strictly in accordance with relevant standards and specifications, and the spacing should be determined by referring to the results of fire risk analysis and the allowable heat radiation intensity of the facility.
The rationality and implementability of planning and layout should take into account the surrounding environment, plant functional positioning, phased implementation strategy and other factors. First of all, the location of LNG storage tank groups is determined according to the shape of land land range of the reserve base, the location of the wharf and other factors. The layout of the storage tank groups is determined according to the total number of storage tanks in the long-term planning and the shape of the site. Secondly, the location of the process plant area should be determined according to the process flow and the location of seawater intake and drainage outlet. The process flow should be smooth, the pipeline should be short, and enough space should be reserved for subsequent development. The tank truck loading area should be close to the storage tank area to shorten the length of the cryogenic pipeline, and should be close to the external main road. At the same time, reasonable driving routes should be set up and the tank truck security waiting area should be planned. The implementation of public works should be arranged close to the load center to reduce the length of conveying pipelines or cables and reduce the investment. Thirdly, the location of administrative office and living service area is determined based on the site, surrounding environment, supporting facilities and wind direction. After the location of each major functional area is basically determined, the layout of public works and auxiliary production facilities should be rationally optimized, station and yard space should be rationally utilized, and land utilization coefficient should be improved.
The layout of LNG reserve base can be divided into several different forms according to the shape of land, the scale of construction and the content of planned construction. Taking the project scale of 20 storage tanks as an example, three different layout methods are studied according to the shape of land use.
If the land is in a strip shape, 10 storage tanks (divided into two rows) can be arranged on each side of the plant, and the process plant area and other auxiliary production facilities can be arranged in the middle. The storage tank area and process plant area on one side will be constructed in the first phase, while the other side will be reserved as a whole. The auxiliary inspection facilities can consider the equipment expansion space reserved in the same area. A reserve railway line and railway tank car loading station can be arranged horizontally beside a storage tank group area. In this arrangement, the facilities constructed in the first phase are relatively concentrated, and the long-term facilities are overall reserved and arranged independently. The pipeline, pipe gallery and other facilities constructed in the first phase do not need to think too much about reserving the long-term capacity and saving the investment. However, after completion, the two storage tank groups are separated by the process equipment and other facilities, and the distance between them is relatively long.
If the shape of the land is square, the storage tank group shall be divided into 4 rows (5 tanks in each row) and centralized layout. The first phase process device shall be arranged next to the storage tank group constructed in the first phase, and sufficient space shall be reserved for the future. The tank truck loading area shall be arranged around the plant, and the other areas shall be arranged for public works and administrative offices. Reserved railway lines, railway tank car filling stations and railway tank car filling lines can be planned and arranged around the plant or near the storage tank group area. The planning of railway filling lines shall not affect the passageways of each entrance and exit of the plant. In the first phase of construction, the layout is relatively scattered and there are more empty Spaces in the middle of the factory. Later expansion needs to be carried out in the middle of the factory. However, after completion, the whole system is a statistical whole.
The storage tank group can also be arranged in L-shape according to the length of the land. For example, two rows of 8 storage tanks are arranged in each row, and the remaining 4 storage tanks are arranged on one side of the storage tank group in a square shape. The layout principles of process equipment and other facilities are the same as the above two methods.
conclusion
A large number of domestic LNG receiving stations have been put into production, with mature layout technology and rich experience. However, with the adjustment of the policy, the subsequent construction of large LNG reserve base has become a trend. By analyzing the function, composition and layout principles of large LNG reserve base, this paper proposes three different layout methods for the planning and layout of large LNG reserve base, which provides ideas and references for the implementation of subsequent projects.
In the early years, LNG glass fiber elastic felt technology was mainly produced by overseas imports. With the investment and development of new energy industry, China has gradually improved the LNG storage tank insulation industry.