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Those who have worked on VOCs incineration RTO projects are aware that Section 6.5.5 of the \"Technical Specifications for the Treatment of Industrial Organic Waste Gases by Regenerative Combustion Method\" (HJ1093-2020) requires that the explosion-proof and pressure-relief design for VOCs treatment projects shall comply with the relevant provisions of GB 50160. The standard-setting expert group later provided a clarification: when it is indeed necessary to install explosion-proof pressure relief devices/facilities, their installation location can be determined based on the actual conditions of the project; they do not necessarily have to be installed on the RTO unit itself. If necessary, explosion-proof pressure relief design can be carried out at the pipeline locations within the RTO project in accordance with relevant regulations. In addition, Point 6 of the \"Safety Key Points for Regenerative Thermal Oxidizers (RTOs)\” issued by the State Council’s supervision team requires that pressure relief valves be installed in the RTO pipelines or furnace chamber. In this way, blast vents and blast doors are both options; generally, blast vents are used for pipes, while blast doors are used for RTO units! Today we will share the requirements regarding the burst discs for RTO systems; feel free to discuss! 【Practical Tips】I. Regulatory and Standard References 1. HJ1093-2020 – Explosion-proof pressure relief design. As mentioned in the introduction, according to clause 6.5.5 of the Technical Specifications for the Treatment of Industrial Organic Waste Gases by Regenerative Combustion, the explosion-proof pressure relief design for RTO systems must comply with GB 50160, the Fire Protection Design Code for Petrochemical Enterprises. It must be emphasized that the concentration of exhaust gases entering the RTO at the inlet stage must be below 25% of the lower limit of the explosive limit. The flame arrester + burst disc pipeline system requires the installation of a flame arrester, with burst relief devices to be installed in the intake pipelines and furnace. 2. Stricter requirements in local standards: For example, Jiangsu Province’s \"Safety Technical Requirements for Regenerative Incinerator Systems (Trial)\\" (Su Ying Ji [2021] No. 46) stipulates that explosion vents must be installed; the intake pipelines must be equipped with such vents, and the furnace body should also have explosion relief mechanisms, with the direction of these vents being such that they do not face areas where people are present. Calculation of explosion venting area: It is recommended to refer to the API-520 standard, with a design basis of \"6.6㎡ per 100m³ of volume\" to ensure rapid pressure release. In addition, another standard worth mentioning is that according to Clause 5.1.5 of the \"Fire Protection Standards for Engineering Design of Fine Chemical Enterprises GB51283-2020 (2020 Edition)\", when VOC waste gas treatment facilities such as thermal oxidation furnaces are used, a high-temperature interlock protection system for the combustion chamber as well as an overpressure relief device for the combustion chamber must be installed. It is also advisable to have a system for monitoring the concentration of incoming gas and to implement interlocks in case of high concentrations, along with flame arresters and relief devices in the waste gas pipelines. II. Selection and Technical Requirements for Explosion Vent Discs (Experience Sharing) 1. Prefer arch-shaped explosion vent discs. Arch-shaped disc with grooves (operating pressure ratio of 0.9) offers advantages such as no fragmentation, high fatigue resistance, and no sparking upon impact, making it particularly suitable for high-temperature and high-pressure RTO environments. The applicable media include particulate-laden, easily polymerizable, or corrosive waste gases. The reverse-dome rupture disc offers better sealing performance, thereby minimizing the risk of leakage. 2. Explosion venting area and installation location: For dual protection of pipes and the furnace, explosion vents should be installed at the front end of the intake pipes and on the top of the furnace, to ensure rapid response near the source of pressure. In the design of vent pipes, the cross-sectional area must be larger than the relief area of the rupture disc. Large-radius elbows should be used, along with drain holes, to prevent blockages caused by fluid accumulation. III. Key points for the safe operation and maintenance of rupture discs 1. Regular replacement: Rupture discs must be regularly inspected and replaced to prevent fatigue failure caused by prolonged exposure to high stress. 2. Integrity of related explosion-proof systems: Fire arresters that meet the GB/T 13347 standard must be installed on the pipelines in front of the fire arresters, to prevent backflow from triggering chain reactions. In anti-static designs, metal pipes must be grounded, while non-metallic pipes require the installation of static discharge devices to eliminate the risk of static electricity accumulation. There was once an RTO accident – an explosion at an chemical plant in Jiangsu – in which the absence of blast vents and concentration monitoring led to equipment damage. Subsequent corrective measures include installing multiple blast relief discs at various locations, as well as placing blast relief membranes at key points along the pipes to provide layered protection; these are all practical lessons learned that must not be ignored!