For reboilers with fire-tube heating, should the spacing of the equipment be determined based on the considerations for open-flame equipment?
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Dear colleagues: We are currently developing a device for the dehydration of triethylene glycol (TEG). The main process involves the counter-current contact between triethylene glycol with low moisture content (lean liquid) and natural gas in an absorption tower; this contact enables the removal of moisture from the natural gas. The dehydrated natural gas is sent to downstream units, while the triethylene glycol that has absorbed water is referred to as rich liquid. In a regeneration tower, heat is supplied via a reboiler, which causes the moisture to be desorbed. The resulting water vapor is discharged outside, while the bottom product of the regeneration tower consists of lean triethylene glycol, which is then pumped back to the absorption tower to enable continuous absorption and regeneration. The reboiler uses a fire-tube heating design, with purified natural gas serving as the fuel. This fuel is burned through combustion nozzles, and heat is transferred to the surface of the fire tubes via flame radiation and convection; these fire tubes then heat the glycerol-rich fluid, thereby enabling desorption. Are there any layout spacing requirements between this type of reboiler and other Class A equipment? Section 5.2.3 of GB50160 states that the bottom reboiler and other equipment closely related to the main equipment can be connected directly or arranged in close proximity ； Is this kind of reboiler suitable for open-flame equipment? Thank you
This post was last edited by altpage on 2018-9-21 at 16:53. It is a heating furnace with specific spacing requirements； Even if the spacing requirements are met, the system risk remains extremely high; a rupture in the fire tubes could lead to a fire and explosion throughout the regeneration tower ； Why not use steam or molten salt as heat transfer media?
Due to the isolated island environment, the utilities are not available； Load restrictions were also encountered with electric heating ； Therefore, a fire-tube heat exchanger is used ； This type of heat exchanger is widely used in triethylene glycol dehydration units; I’m just not quite sure what the specific fire separation requirements are GB50160 mentions that the combustion furnaces used in Claus sulfur recovery processes do not need to be considered as open-flame equipment; however, due to process requirements, it is not clear whether this reboiler can also be treated in a corresponding manner... GB50183 also does not mention this...
Have there been any results? It happens to relate to this area right now as well
Table 5.2.2-2 of GB50183 \"Code for Fire Protection Design of Petroleum and Natural Gas Engineering\" – Fire separation distances within installations: Note 2 specifies that clear requirements are set forth: \"For integrated units consisting of heaters, separators, and related facilities, triethylene glycol flame-heated regeneration vessels, direct-flame-heated reboilers used for solution desulfurization, and other devices that utilize direct flame heating, the fire separation distances shall be determined based on the locations where open flames exist or where sparks are generated.\"
There is indeed a requirement for this. There is one more thing I would like to ask: are there any requirements regarding the triethylene glycol flame-heated regeneration tank and its regeneration solution buffer tank, and do they meet the requirements specified in Table 5.2.2-2?
The distillation column, reboiler, stripping column, and lean liquid buffer tank can be considered as a whole
Indeed, that is indeed what is being done at the moment