How to select a burst disc for an atmospheric pressure reactor
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The company has an atmospheric pressure reactor that uses organic solvents and involves reflux operations. From a safety perspective, we need to install burst discs on the vent pipe of the reactor. The equipment supervisor believes that since it is an atmospheric-pressure reactor, only a rupture disc with a pressure rating of 0.01 MPa can be installed. However, the operation of our reactor involves the following steps: 1. The reactor uses vacuum feeding to add materials ； 2. The reaction vessel discharges material by using nitrogen pressure, rather than through a discharge valve located at the bottom of the vessel ； 3. The operation of purging the reactor with nitrogen. Of course, misoperations can be avoided through standard operating procedures, but even a slight misoperation can cause the rupture disc to fail, as this 0.01 MPa rupture disc is simply too small. I want to get a larger one; I checked the equipment label, and the design pressure for the atmospheric-pressure reactor is – atmospheric pressure ； Work stress – normal pressure ； Maximum allowable operating pressure — atmospheric pressure. And our equipment supervisor insisted that only models with a pressure of 0.01 MPa could be installed. Although we can install a larger one on our own, such as a rupture disc with a pressure rating of 0.2 MPa, I still hope to find some evidence to support this. Does anyone who is familiar with this matter know how to select a rupture disc in such situations?
0.01 isn’t effective; 0.2 is too high. How about 0.09? My safety valve is just like this.
It is not necessary to install rupture discs in pressure vessels at normal pressure. According to the \"Regulations on Safety Supervision of Fixed Pressure Vessels\" TSG R0004—2009: When a rupture disc device is installed on a pressure vessel, the designed burst pressure of the rupture disc shall generally not be greater than the designed pressure of the vessel, and the minimum burst pressure of the rupture disc shall not be less than the operating pressure of the vessel. The design pressure is at atmospheric pressure; we consider it to be 0. If a burst disc value of 0.01 is chosen, it should not comply with relevant standards ； There is such a problem: personally, I think the choice of container design by you is unreasonable ； The design pressure of your reactor – atmospheric pressure ； Work stress – normal pressure ； Maximum allowable operating pressure – atmospheric pressure ； Based on your description, it is clear that the actual pressure under your operating conditions exceeds the maximum allowable design pressure; this is non-compliant and poses a safety risk.
Firstly, according to Article 5.5.1 of the \"Code for Fire Protection Design of Petrochemical Enterprises (GB50160-2008)\", safety valves shall be installed on the following equipment that may experience overpressure under abnormal conditions – 5. Equipment in which combustible gases or liquids expand due to heat and may exceed the design pressure. Although this is about safety valves, it is precisely because of this requirement that the safety supervision agency demands that we install either safety valves or burst discs. Moreover, our local safety supervision agency issued a document a few years ago requiring that all reaction units involving organic solvents must be equipped with pressure relief devices. There’s no way to explain this! Secondly, I believe that even in ordinary atmospheric-pressure reaction vessels, using vacuum to feed materials in and nitrogen pressure to discharge them (at a pressure of about one or two kilograms, with the pressure being increased gradually) should not pose any problems. Finally, what bothers me is that pressure vessels are defined by parameters such as \"operating pressure,\" \"design pressure,\" and \"maximum allowable operating pressure.\" Are all atmospheric-pressure reactors really “at atmospheric pressure”? Is this thing just made of paper? Is there no range?
Then install a safety valve; it will be the same as my setup
If the code requirements are met, it is recommended to install a breathing valve instead of a rupture disc.
There is a problem with the design; since your process requires nitrogen at a pressure of two kilograms to carry out the discharge, why not use a pressure vessel? There’s no need to worry about anything anymore.
According to the \"Regulations on Safety Inspection of Fixed Pressure Vessels\" TSG R0004—2009, pressure vessels operating at atmospheric pressure do not require the installation of burst discs. However, for safety reasons and in line with the requirements of the manufacturing process, the reaction vessels designed and operated by our company are also designed for use at atmospheric pressure. Nevertheless, we install burst discs on the reaction vessels used in polymerization processes
Many atmospheric-pressure reactors in the fine chemicals workshop are used for various reactions; typically, nitrogen is used to displace air from the reactors, and after the reaction, nitrogen is used to protect the contents during discharge, which is why explosion-proof valves are installed on these reactors
The design pressure of the burst disc is greater than the operating pressure and less than the design pressure of the equipment