Flame Resistance Characteristics and Its Influence Mechanism

Inhaltsverzeichnis

1. Frontmatter

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2. 1. Introduction

   • Open Access

   Zhirong Wang, Xingyan Cao

   Abstract

   The transportation of hydrogen has always been a difficult problem restricting the development of hydrogen energy industry (Zhu et al. in Int J Hydrogen Energy 80:1305–1316, 2024; Yu et al. in Energ Convers Manag 301:118025, 2024). As a highly active flammable gas, it is inevitable that hydrogen leakage occurs due to the multiple uncertain factors during its storage and transportation, which is easy to cause serious gas explosion accident. The flame arrester, as an explosion-retardant device, can effectively prevent the propagation of high activity flammable gas explosion flame and is widely utilized in gas transportation pipeline of petrochemical enterprises (Nie et al. in Fuel 362:130822, 2024; Shen et al. in J Loss Prev Process Ind 90:105351, 2024). As a key component for explosion prevention, its failure will lead to incalculable consequences. How to effectively protect hydrogen doped gas explosion is currently a hot and difficult research topic (Wang et al. in Int J Hydrogen Energy 48:34440–34453, 2023).

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3. Wire Mesh Flame Arrester

   1. Frontmatter

   2. 2. Research on the Flame Resistance Characteristics of Wire Mesh for Syngas Explosion

      • Open Access

      Zhirong Wang, Xingyan Cao

      Abstract

      The diagram of experimental apparatus for inhibiting syngas explosion by wire mesh is shown in Fig. 2.1. The main structure has been described in in the previous work. In this experiment, self-designed wire mesh flame resistance system [the effective area (A) = 100 mm × 100 mm] was adopted and installed inside the vessel by the support rod to prevent the flame propagation. Its main structure included four support rods with 5 mm diameter, two support plates with 3 mm thickness and the multi-layer wire mesh (see in Fig. 2.1). The multi-layer wire mesh was compressed by the two support plates and the pre-tightening force was provided by bolts. To improve the fixed strength of support plate, two stiffeners with 5 mm width were uniformity set in the transverse and longitudinal directions of the opening area. The distance between the flame resistance system and vessel bottom end was 650 mm. Based on the previous works, the flame could fully develop in this length of vessel. Besides, two thermocouples and pressure transmitters were correspondingly installed in the wall surface of flame resistance system two ends [the height (h) = 50 mm]. By changing the syngas concentration and wire mesh layer number, the flame resistance mechanism was analyzed in-depth (Cao et al. in Process Saf Environ Protect 175:34–47, 2023).

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   3. 3. Effect of Wire Mesh Structure Parameter on the Flame Propagation Characteristics of Syngas Explosion

      • Open Access

      Zhirong Wang, Xingyan Cao

      Abstract

      Based on the visual experimental apparatus built in the previous work (Cao et al. in Fuel 334:126658, 2023), the experiment on the effect of wire mesh structure on syngas explosion inhibition was conducted. The detailed schematic diagram is shown in chapter one. The main difference from the previous apparatus was that a wire mesh flame resistance system was installed inside the explosion vessel (910 mm × 150 mm × 150 mm) and fixed by four support rods (d = 5 mm). The wire mesh flame resistance system was composed of the multi-layer wire mesh and two support plates (δ = 3 mm). The wire mesh with 100 mm × 100 mm effective flame resistance area was placed inside the two support plates and was compressed by the bolt connection method. The wire mesh flame resistance system was installed at a height of 650 mm (the middle of two pressure transmitters and thermocouples) distance from the bottom end of the vessel. Through previous researches, the height could ensure the acceleration propagation and full development of syngas explosion flame.

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   4. 4. Wire-Mesh Inhibition of Jet Fire Induced by Explosion Venting

      • Open Access

      Zhirong Wang, Xingyan Cao

      Abstract

      As shown in Fig. 4.1, the experimental system consists of an explosion venting system, a data acquisition system, and a gas distribution system (Wang et al. in J Loss Prevent Process Ind 70:104408, 2021).

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   5. 5. Research on the Synergy Inhibition of Ultrafine Water Mist and Metal Wire Mesh on the Syngas Explosion

      • Open Access

      Zhirong Wang, Xingyan Cao

      Abstract

      Figure 5.1 presents the structural diagram of experiment apparatus for the synergy inhibition of syngas explosion using the ultrafine water mist and metal wire mesh. The main structure was introduced in detail in the previous work (Cao et al. in Int J Hydrogen Energy 70:1089–1100; 2024). This experimental apparatus was mainly equipped with a metal mesh flame resistance system and a spray system. The flame resistance system consisted of two wire mesh press plates, the multi-layer metal wire mesh (the stainless steel) and four support rods. The metal wire mesh was made of 304 stainless steel material and its thermal conductivity was 16.3 W m⁻¹ K⁻¹ at 100 °C. The melting point could reach 1457 °C. The wire mesh with determined layer and mesh numbers was placed inside the press plate, and four support rods were adopted to support it. The wire mesh was compressed tightly and the height of press plate was adjusted through bolts (Effective area: H × D = 100 mm × 100 mm). To ensure the same compression strength, a metal compression ring with a certain height was installed on the internal support rod of press plate and tightened with bolts. The structure size of press plates was designed and processed based on the cross-sectional area of explosion vessel to achieve close integration. Meanwhile, the gap of wall surface and the press plate was blocked by the vacuum sealing mud. The spray system included a water storage tank, a solenoid valve, one-way valve and a fine nozzle, as shown in Fig. 5.1. The fine nozzle was installed at the bottom end of vessel top flange. The water storage tank was filled with the deionized water and its internal pressure was determined by a precision pressure gauge. By controlling the opening and closing of the solenoid valve through the program, the different spray time was achieved.

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   6. 6. Research on the Synergy Effect of Resistance/Inhibition on the Syngas Explosion

      • Open Access

      Zhirong Wang, Xingyan Cao

      Abstract

      Figure 6.1 illuminates the experimental setup for the synergistic effect of resistance/inhibition on the syngas explosion. The main structure has been mentioned in the previous experiments. The pressure spray system and wire mesh explosion-resistant system were added to the experimental apparatus. The pressure spray system was composed of fine spray nozzle, one-way valve, solenoid valve and water storage tank. The nozzle was installed on the lower end of top flange through threaded connection method. The water storage tank was filled with the deionized water to eliminate the factors affecting explosion inhibition and the spray pressure was provided by the gas cylinders. The mist parameter was altered by changing the nozzle type and spray pressure. The moment and duration of spray were achieved by controlling the opening and closing of solenoid valve, further changing spray amount at the upper end. Under the action of pressure, the fine atomization solid nozzle conducted spray at an angle of 60°. The cross section of the vessel was 150 mm × 185 mm. The internal high of vessel was 910 mm and the height of the nozzle was 40 mm after connecting to the top flange. By calculation, the distance between the nozzle and the wire mesh explosion-resistant system was 210 mm. At a spray angle of 60°, the corresponding mist zone width at a height of 210 mm was 144.6 mm and it was less than the wall surface distance. This indicates that the water mist produced by pressure spray was mainly distributed inside the vessel. However, the movement velocity of micrometer scale mist was sharply reduced as the distance increased due to the drag force although the mist near the nozzle had a high movement velocity. And most of the mist would be suspended in the upper end of the flame resistance system within the millisecond spray and standing times.

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   7. 7. Research on the Synergy Effect of Water Mist Containing Additives and Flame-Retardant System on the Syngas Explosion Inhibition

      • Open Access

      Zhirong Wang, Xingyan Cao

      Abstract

      The explosion resistance/inhibition apparatus is presented in Fig. 7.1. The detailed instruction had been stated in the previous experiment work. Here, only the explosion-inhibition system (Pressure spray system) and flame-retardant system (Metal wire mesh system) were introduced. The pressure spray system included a stainless steel water storage container, a solenoid valve, a check valve and a pressure nozzle. The deionized water was loaded into a storage tank and the additive was dissolved into it. The inhibition condition was adjusted by changing the additive condition (its type and mass fraction) and the spray pressure. By controlling the solenoid valve, the spray moment and duration were adjusted, thereby changing the mist concentration at the upper part of flame-retardant system. The flame-retardant system with square cross-section (100 mm × 100 mm) was mainly composed of two layer pressure plates with 3 mm thickness, multi layer wire mesh and four supporting rods. The wire mesh was compressed inside two pressure plates by adjusting nut height. The flame-retardant system was installed on the supporting rod with a determined position (H = 650 mm). To guarantee the fixed compression strength of wire mesh under the same working condition, four equally high metal gaskets were installed between the two pressure plates.

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4. Corrugated Flame Arrester

   1. Frontmatter

   2. 8. Research on the Resistance Characteristics of Corrugated Flame Arrester for Hydrogen Explosion

      • Open Access

      Zhirong Wang, Xingyan Cao

      Abstract

      The visualization experimental apparatus used to study the flame resistance characteristics of hydrogen explosions with a corrugated flame arrester is illustrated in Fig. 8.1. The main framework of this apparatus has been detailed in previous work (Cao et al. in Int J Hydrogen Energy 88:228–241, 2024). This section focuses specifically on the corrugated flame-retardant system, which comprises the flame-retardant unit and its shell, upper and lower pressure plates, and four threaded support rods. The multilayer flame-retardant units are tightly stacked using the upper and lower pressure plates and are housed within the flame-resistant unit shell. The system is secured by the threaded support rods, with height adjustments made via nuts. By varying the ripple height and the number of flame-retardant units, the structural parameters can be altered. A self-processed flame-retardant unit with a thickness of 20 mm and the diameter of 110 mm was adopted.

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   3. 9. Research on the Resistance Characteristics of Corrugated Flame-Retardant System for Hydrogen–Methane Explosion

      • Open Access

      Zhirong Wang, Xingyan Cao

      Abstract

      The experimental apparatus of corrugated flame-retardant system was shown in Fig. 9.1. The main part had been detailed in the previous work. Only a detailed explanation was introduced for the corrugated flame-retardant system. It consisted of the flame-retardant element shell, the flame-retardant element, the flame-retardant pressure plate, and four threaded support rods. The flame-retardant system was made of 304 stainless steel and its thermal conductivity was 16.3 W m⁻¹ K⁻¹. Multilayer flame-retardant elements were tightly stacked inside the flame-retardant element shell and was fastened by bolts, and placed inside the upper and lower flame-retardant pressure plates. The flame-retardant pressure plates with four through-holes at the diagonals were installed on the support rod with a determined height (H = 650 mm). By changing the length of flame-retardant element shell and the number of flame-retardant element, the structural parameters for different corrugated flame-retardant systems were achieved. To ensure a tight joint between the flame-retardant system and the inner wall surface, the gaps was sealed by the high temperature explosion-proof sealing mud. Two visualization windows were installed at the front and rear ends of explosion vessel to capture the transient transformation process of flame structure obstructed by the flame-retardant system and the propagation change after passing through the narrow channel.

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   4. 10. Effect of Obstacle Parameters on Explosion Resistance Performance of Hydrogen Crimped-Ribbon Flame Arrester

      • Open Access

      Zhirong Wang, Xingyan Cao

      Abstract

      Figure 10.1 illustrates a schematic diagram of experimental apparatus for studying the explosion resistance performance of hydrogen crimped-ribbon flame arrester under the presence of obstacles. The main body included the explosion pipe (including an unprotected pipe (L₁ = 2 m) and a protected pipe (L₂ = 2 m)), a flame arrester (including flame arrester element and expansion chamber structure), an obstacle group, a gas distribution system, an ignition system, a flame acquisition system, a pressure acquisition system, a temperature acquisition system and a program control and data acquisition system (Wang et al. in Int J Hydrogen Energy 48:34440–34453, 2023).

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   5. 11. Research on Quenching Performance and Multi-factor Influence Law of Hydrogen Crimped-Ribbon Flame Arrester Using Response Surface Methodology

      • Open Access

      Zhirong Wang, Xingyan Cao

      Abstract

      The schematic diagram of the experimental apparatus was shown in Fig. 11.1. According to the ISO 16852 standard, the experimental apparatus was built, including an unprotected pipe (L₁ = 2 m), the flame arrester (flame arrester element and expansion chamber structure), a protected pipe (L₂ = 2 m), a high-voltage ignition system, a gas distribution system, a pressure acquisition system, a flame detection system, a data acquisition system, and a synchronous controller (Lin et al. in Fuel 326:124911, 2022).

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   6. 12. Multi-factor Influencing on Detonation Quenching Performance of Crimped-Ribbon Flame Arrester

      • Open Access

      Zhirong Wang, Xingyan Cao

      Abstract

      In the previous chapter, the graphic illustration of the experimental apparatus was provided. In this case, the lengths of detonation and protected pipes were 4000 mm and 2000 mm separately. The flame arrester (FA) equipment consisted of flame arrester element (CF-E) and expansion chamber (EC). In the experiment, the CF-E with different porosities and element thicknesses were used. Then, different EC (the conventional, baffle, and extended types) were adopted to connect with the CF-E. There were three types of EC with the same volume and their only difference was in the internal structure, as shown in Fig. 11.2. In contrast to the conventional EC, the baffle-type EC had an internal annular baffle (inside diameter: 70 mm), which was 30 mm and 240 mm away from the CF-E and the flange end face. Besides, the tube with 155 mm was mounted in the extended EC and the circular hole with 12 mm were evenly distributed along the circumferential direction of tube port (Lin et al. in J Loss Prev Process Ind 87, 2024).

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