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As core facilities for energy strategic reserves and civilian energy supply, liquefied hydrocarbon stations require their design and operation to take into account efficient storage, intrinsic safety, and environmental protection requirements. Storage tanks in large liquefied hydrocarbon facilities are mostly of spherical design; compared to traditional cylindrical tanks, spherical tanks exhibit better stress distribution characteristics. For the same volume, the spherical shell minimizes its surface area (reducing material consumption) while evenly withstanding internal pressure. Under the same pressure and diameter, theoretically the wall thickness of a spherical tank needs to be only 1/2 of that of a cylindrical tank. 1. Subdivision of liquefied hydrocarbon sphere tank types: A sphere tank for liquefied hydrocarbons at normal temperature refers to a full-pressure type tank whose design pressure is set at or above the saturated vapor pressure of the liquefied hydrocarbon medium at 50°C. Due to the high pressure and thick wall thickness, it is not easy to increase the volume of spherical tanks. Moreover, the larger the volume, the greater the risk in case the medium with a large storage capacity leaks. **The standard – the \"Code for Fire Protection Design of Petrochemical Enterprises\" GB50160-2008 – includes the following new clause in its 2018 revision: 6.3.1A The volume of a single full-pressure or semi-refrigerated liquefied hydrocarbon storage tank shall not exceed 4000 m³. In 2024, the **Ministry of Emergency Management issued new capacity limits – the latest regulations regarding spherical tanks and their main impacts on the spherical tank industry. For semi-frozen spherical tanks, when the pressure of the medium at room temperature is high and it is not possible to achieve a tank volume of 4000 cubic meters, the design of larger spherical tanks can be accomplished by reducing the temperature and pressure. Such spherical tanks are known as semi-frozen spherical tanks. This design helps to reduce the initial investment in the facility, but it also increases the operational and maintenance costs of the facility. Ultra-low temperature spherical tanks generally refer to double-vacuum cryogenic spherical tanks with a design temperature below -196°C, suitable for storing large quantities of special fluids such as liquid hydrogen and liquid helium. 2. Volume data of several large spherical tanks: 1) In the 1980s, China built a semi-cold liquid ammonia spherical tank with a volume of 8250 m³ (using imported materials, with a design pressure of 0.4 MPa). Subsequently, a number of liquid ammonia spheres with capacities of 5,000 m³ and 6,000 m³ were built (using domestically produced materials, with a design pressure of less than 1.0 MPa). 2) The volume of natural gas spheres independently built in our country has reached 10,000 m³. 3) The largest vacuum spherical tank currently built in China has a capacity of 20,000 m³. 4) The development of large-scale spherical tanks in Europe and the United States started earlier, and the technology is also more mature. For example, Germany already has the capability to produce spherical tanks with a volume of over 43,300 m³; France also possesses experience in manufacturing spherical tanks with a volume of 87,000 m³. In the United States, the volume of Hallon-type spherical pressure tanks has reached 160,000 cubic meters. Spherical tanks for liquid hydrogen that have been built and put into use have a capacity of 4,700 m³, with a design temperature of -253°C. 3. During safety inspections, the layout of liquefied hydrocarbon spheres gives rise to the following layout-related issues: 1) The distance between spheres is not in accordance with the specified standards. The distance referred to here is the distance between the outer walls of the spheres (or the outer wall of the insulation layer, in the case of spheres with insulation layers). Some designers tend to arrange the design based on the inner diameter of the spherical tank, ignoring factors such as the wall thickness of the tank, the thickness of the insulation layer, construction errors in civil engineering, and construction errors of the spherical tank itself. Currently, portable laser rangefinders are generally used for inspections, and it is easy to detect any non-compliance with the specifications. Relatively speaking, it is easier to make corrections when it is found during the drawing approval process that the spacing requirements are not met; generally, it is sufficient to reduce the inner diameter of the spherical tank accordingly. 2) The spherical tank area is not located on the outside of the site or as a separate zone, nor is an independent transportation passage provided on the side close to the road. The main purpose is to shorten the routes taken by tankers transporting liquefied hydrocarbons within the plant, thereby reducing unnecessary risks. 3) There are no physical walls between the tank area and other parts of the plant. 4) The liquefied hydrocarbon spheres and the storage tanks for oils at atmospheric pressure were not arranged separately, as required by the latest version of the \"Design Code for Oil Storage Tanks\".