Parameters of large low-temperature LPG transport ships
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This post was last edited by xahoo on 2018-9-17 at 09:47. Currently, the main type of large-scale low-temperature LPG transport ships in use internationally is those with a capacity of 4×104 DWT; their weight is 44,000 tons and their maximum volume is 74,000 m3. LPG transport ships feature separate compartments of type A. According to available information from Jiang Shipyard, there are 4 such separate compartments. My question is: do these LPG ships carry multiple types of materials, or is each compartment used for carrying one specific type of material, such as low-temperature propane? In other words, in a grade-1 LPG terminal, it’s fine to transport propane and butane in 40,000-LPG tanks separately; can they be transported and unloaded together?
LPG ships can only carry LPG. The four separate compartments can only hold LPG; they cannot hold other liquids, and it is a specialized vessel. Consider that when switching to a cryogenic liquid, the system must be purged again, and attention must also be paid to pipeline corrosion and the properties of the medium.
This post was last edited by xahoo on 2018-9-13 at 16:34. Domestic LPG Class 1 storage facilities generally use large cryogenic propane tanks; when considering the tank capacity for LPG storage, does \"LPG ship\" refer to cryogenic propane ships? Butane tanks are small – what type of ship is used for low-temperature butane, and how should the size of the butane storage tanks be determined?
According to the regulations specified in TSG R0006-2014 \"Technical Regulations for Safety Inspection of Gas Cylinders\", and by referring to relevant manuals, the saturated vapor pressure of isobutane at 50°C is 0.79 MPa; therefore, its operating pressure is also 0.79 MPa. The setting pressure pz of the safety valve is determined based on the operating pressure; generally, pz is taken as (1.05–1.1)pw, which is 0.83–0.87 MPa. The design pressure p of the container is set to be equal to or slightly greater than the set pressure pz; that is, p≥pz=0.87 MPa. Therefore, the design pressure for the isobutane storage tank is set at 0.87 MPa.
Theoretically, a single hold can be used to load and unload different types of cargo, but whether it can dock depends on the requirements of the regulatory authorities