氢气危险区域应用的IIC 或 IIB+H2防爆外壳设计

氢气是地球上最丰富但最危险的气体之一。它用途广泛，将成为能源转型的重要组成部分，但预防爆炸对于整个供应链的成功至关重要。

Ex-tech Solution 的 Laurent Thomassin 谈到了氢气爆炸的科学原理，以及氢气应用的防爆外壳为何与石油和天然气行业中常见的外壳不同。

Hydrogen is one of the most abundant but dangerous gases on our planet. It has many uses and is set to form a big part of the energy transition, but the prevention of explosions is critical to its success throughout the supply chain.

Laurent Thomassin from Ex-tech Solution talks about the science of hydrogen explosions and why explosion proof enclosures for hydrogen applications are different to those typically found in the oil and gas industry.

什么是氢气，它是否易燃？

What is hydrogen and is it flammable?

氢是地球上最丰富的元素，能够通过化学反应产生能量，因此对氢的需求量很大也就不足为奇了。这种无色、无味的气体，即氢气（H2），无毒无放射性，用途广泛。

Hydrogen is the most abundant element on earth and capable of chemical reactions that generate energy, so it’s no wonder that hydrogen is in great demand. This colourless, odourless gas known as H2 is also not toxic or radioactive, and so has many different uses.

近年来，氢能和燃料电池技术已显示出巨大的潜力，有助于实现向清洁、低碳能源系统的过渡，从而减少温室气体排放并限制气候变化。当氢气燃烧或用于发电时，唯一的废物就是水。

然而，在使用氢气时也存在挑战。它极易燃烧，被认为是很危险的气体之一，具有多种独特性质，如果没有正确的理解和防爆设备，处理氢气会很危险。

Over recent years, hydrogen and fuel cell technologies have shown significant potential to enable the transition to a clean, low-carbon energy system that helps reduce greenhouse gas emissions and limit climate change. And when hydrogen is burnt, or used to produce electricity, the only waste product is water.

However, there are challenges when using it. It is extremely flammable and considered one of the most dangerous gases, with several unique properties that make it dangerous to handle without the correct understanding and explosion protection equipment.

如何制造氢气？

How is hydrogen made?

制造氢气的方法有很多种，但它们都涉及使用化学、电、热、核或可再生能源从化合物（含氢物质）中分离出氢气。

There are many different ways to make hydrogen but they all involve splitting off the hydrogen from a compound (a substance containing hydrogen) using chemical, electrical, thermal, nuclear or renewable energy.

风力发电—制氢

Wind power generation - Hydrogen

这需要大量的能量！

It takes a lot of energy!

水原子电解是通过电流生产氢气的最佳方法之一，并且被认为是环保的，因为使用风能或太阳能时不会产生二氧化碳。这被称为绿色氢气，近年来发展迅速。另一方面，灰氢对环境有害。

Electrolysis of water atoms is one of the best methods to produce hydrogen by electric current and is considered environmentally friendly with no carbon dioxide produced when wind or solar is used. This is known as green hydrogen which has grown over recent years. Grey hydrogen on the other hand is harmful to the environment.

为什么 2025 年氢气的需求会更大？

Why is hydrogen more in demand in 2025?

更多人认为绿色氢是清洁能源结构和未来燃料的基本组成部分。

Green hydrogen is considered by many as a fundamental part of the clean energy mix and the fuel of the future.

此外，在运输系统中使用时，它不会产生尾气排放。然而，整个供应链都存在爆炸风险。

Furthermore, when used in transport systems it produces no tail-pipe emissions. However there are explosion risks throughout the supply chain.

氢气爆炸的科学

The science of hydrogen explosions

与所有其他易燃物质一样，只有当燃烧三要素的所有三个部分结合在一起时才会发生爆炸。这与氢气没有什么不同。请参见右侧的火三角图。

对于氢气，火灾和爆炸会燃烧极热。但更可怕的是，它燃烧时会产生肉眼看不见的火焰。

氢气爆炸时也会产生巨大的能量，只需要少量的气体就能造成重大损害，从而导致熔化并进一步在周围区域引起火灾和爆炸。

氢气的爆炸范围非常大，火焰速度很快，这意味着氢气爆炸导致的压力迅速增加，这对于防爆规范尤为重要。

Like all other flammable material, an explosion can only occur when all three parts of the ignition triangle come together.  That’s no different to hydrogen. See fire triangle diagram on the right.

With hydrogen, the fire and explosion burns with extreme heat. But what is more frightening, is that it burns with an invisible flame (to the human eye).

Hydrogen also explodes with enormous energy, requiring only a small amount of gas to cause significant damage which can lead to melting and further fires and explosions in the surrounding areas.

Hydrogen’s extremely large explosion range and high flame velocity means the resulting rapid pressure increase of hydrogen explosions are of particular importance for explosion protection specifications.

换句话说，氢气的防爆需要与天然气的防爆不同。

In other words, explosion protection for hydrogen needs to be different to that of natural gas.

此外，氢气在化学计量混合时具有非常低的最小点火能量 (MIE)，仅为 0.0017 毫焦耳 (mJ)。这意味着它可以被大多数来源轻松点燃。这比其他可燃气体（如甲烷）低得多，甲烷的 MIE 通常超过 100 mJ。

根据欧洲 ATEX 进行的风险评估，导致危险区域分类，并因此需要具有适合氢气的正确设计规格的防爆设备。

Furthermore, Hydrogen has a very low minimum ignition energy (MIE) of just 0.0017 millijoules (mJ) at a stoichiometric mixt. That means it can be easily ignited by most sources. This is significantly lower than other flammable gases, like methane, which typically have an MIE of over 100 mJ.

Risk assessments according to ATEX in Europe, lead to the classification of hazardous areas and the resulting need for explosion proof equipment with the correct design specifications for hydrogen.

氢气是一种 IIC 气体，与天然气不同。但为什么这很重要？

Hydrogen is a IIC gas which is different to natural gas. But why does that matter?

所有已知气体都根据其最小点火能量 (MIE) 分为几类，MIE 是指用电火花点燃气体所需的能量。

IIC 类气体的 MIE 最低，这意味着该类气体挥发性极强，容易点燃。 IIC 类气体包括氢气、乙炔和二硫化碳。

All known gases are categorised into groups based on their minimum ignition energy (MIE), which is the amount of energy required to ignite the gas with an electrical spark.

The IIC group has the lowest MIE, meaning that the gases in this group are highly volatile and easily ignited. Gases in the IIC group include hydrogen, acetylene, and carbon disulphide.

相比之下，IIA 类包含丙烷和丁烷等气体，IIB 类包含乙烯和乙醚，这些气体不太易挥发或点燃，但仍然非常危险。

By contrast, Group IIA contains gases like propane and butane, and Group IIB contains ethylene and ethyl ether which aren’t as volatile or easy to ignite, but highly dangerous, nonetheless.

因此，IIC 组是气体组中最严重的组，标记为可用于 IIC 区域的设备也可以用于 IIB 和 IIA 区域。但是，标记为可用于 IIB 区域的设备只能用于 IIB 和 IIA 区域，不能用于 IIC 区域。

务必使用针对该区域最易挥发气体进行评级的设备。

The IIC group is therefore the most severe of the gas groups, and equipment marked for use in IIC areas can also be used in IIB and IIA areas. However, equipment marked for use in IIB areas can only be used in IIB and IIA areas, and not in IIC areas.

It’s important to use equipment rated for the most volatile gas in the area.

氢气危险区域应用的防爆外壳设计

The design of explosion proof enclosures for hydrogen hazardous area applications

典型的防爆 ex d 外壳通常用于容纳工厂或加工区危险区域中的电气设备。Ex d 外壳的工作原理是控制爆炸并防止其点燃周围区域。前提是气体首先可以进入外壳。

外壳可容纳爆炸并通过法兰和螺纹消散任何多余的能量。外壳具有冷却和容纳爆炸的火焰通道。

然而，氢气是一种与工业中大多数气体（例如甲烷或丙烷）具有不同特性的气体，这意味着外壳确实需要与大多数危险区域中的外壳不同。

这是因为氢分子较小，可以更容易地穿过狭窄的间隙。因此，防爆外壳的设计需要与 IIA 或 IIB 气体的设计不同。

A typical explosion proof ex d enclosure usually houses electrical items in a hazardous area at a factory or in a process area. Ex d enclosures work by containing explosions and preventing them from igniting the surrounding area. That’s if the gas can enter the enclosure in the first place.

The enclosure contains an explosion and dissipates any excess energy through its flanges and threads. The enclosure has a flame path that cools and contains the explosion.

However, hydrogen is a gas that has different characteristics compared to most gases in industry such as methane or propane for example, which means the enclosures do need to be different than those seen in most hazardous areas.

That’s because hydrogen molecules are smaller and can travel through narrow gaps more easily. The design of the explosion proof enclosure therefore needs to be different to that of a IIA or IIB gas.

IIB+H2 外壳的间隙比 IIB 组外壳更薄，有时间隙更长。IIC 防爆外壳通常具有圆柱形或螺纹式火焰通道，而 IIA 组和 IIB 组外壳具有扁平火焰通道。

IIB+H2 enclosures have thinner and sometimes longer gaps than Group IIB enclosures. IIC explosion proof enclosures often have a cylindrical or threaded flame-path, while Group IIA and IIB enclosures have a flat flame-path.

在危险区域工作时，还必须注意风险并使用具有正确 T 等级（温度等级）的电气设备。

When working in hazardous areas, it’s also important to be aware of the risks and use electrical equipment with the correct T rating (temperature class).

氢气供应链中哪些地方需要防爆？

Where is explosion protection needed in the hydrogen supply chain?

由于氢气具有危险特性，需要防爆保护的场所遍布整个氢气供应链。以下是一些示例：

• 生产：电解厂、石油、天然气、煤炭应用、重整厂、储罐和航运基础设施。

• 存储和配送：终端、能源供应商、运输网络和本地仓库

• 使用：制造工厂在其过程中将氢气转化为燃料、甲醇、氨、钢铁、玻璃、能源、水泥、化学品等等。当然还有运输用户、将氢气输送到天然气管网以及在沼气厂的发酵过程中使用氢气，仅举几例。

The locations where explosion protection is needed span the entire hydrogen supply chain due to its dangerous characteristics. Here are some examples:

• Production: Electrolysis plants, oil, gas, coal applications, reforming plants, storage tanks and shipping infrastructure.

• Storage and distribution: Terminals, energy providers, transport networks and local storage depots

• Use: Manufacturing plants converting hydrogen in their process to fuels, methanol, ammonia, steel, glass, energy, cement, chemicals and much more. And of course transport users, the feeding of hydrogen into the natural gas grid and the use of hydrogen for the fermentation process in biogas plants, to name a few.

原始设备制造商 (OEM)、最终用户和 EPC 正在不断开发新系统和新流程，以支持近年来快速发展的整个供应链中氢气的生产、供应和使用。

OEMs, end users and EPCs are continually developing new systems and processes to support the production, supply and use of hydrogen throughout this supply chain which has grown rapidly in recent years.

Ex d IIB+H2 防爆外壳选项

Ex d IIB+H2 explosion proof enclosure options

防爆外壳用于保护电气和控制系统，例如能量分配、过程监控和机械控制。

氢气防爆外壳必须足够坚固，以承受重大爆炸，例如，外壳的外壁必须保持足够低的温度，以防止点燃外壳外的氢氧混合物。

Explosion proof enclosures are used to protect electrical and control systems, such as energy distribution, process monitoring and machinery control.

The explosion proof enclosures for hydrogen must be strong enough to contain a significant explosion and, for example, the external wall of the enclosure must remain cool enough to prevent igniting a hydrogen-oxygen mixture outside the enclosure.

IIB+H2 不锈钢 Ex d 外壳 – DE8BC

Ex-tech Solution 生产的不锈钢 DE8BC Ex d IIB + H2 防爆外壳，它们具有出色的耐腐蚀性，适用于海洋/海上应用，并且有多种尺寸可供选择。它们可以配置为 Ex d 直接入口或 Ex de 组合用于间接入口。如果需要，可以在带有单独或公共 Ex e/i 接线盒的框架上组装多个外壳。Ex-tech Solutions 可以提供带有 U 组件证书的空外壳，也可以根据客户需求提供完全组装的外壳。

IIB+H2 Stainless Steel Ex d enclosures – DE8BC

Here is an example of the stainless steel DE8BC Ex d IIB + H2 explosion proof enclosures from Ex-tech Solution, which have excellent corrosion resistance for marine / offshore applications, and are available in many sizes. They can be configured as Ex d direct entry or as an Ex de combination for indirect entry. If required, several enclosures can be assembled on a frame with separate or common Ex e/i junction boxes. Ex-tech Solutions can deliver the enclosures empty with a U component certificate, or will supply fully assembled according to customer’s needs.

IIB+H2 无铜铝 Ex d 防爆外壳 – EJB

Ex-tech Solution 的 EJB 系列 Ex d IIB +H2 防爆外壳采用无铜铝制成，设计用于控制、检查、信号、自动化、中断和保护应用。无铜铝通常因其耐腐蚀性和较轻的重量而被指定。

IIB+H2 Copper Free Aluminium Ex d explosion proof enclosures – EJB

Ex-tech Solution’s EJB range of Ex d IIB +H2 explosion proof enclosures are manufactured in copper free aluminium and designed for use in control, check, signal, automation, interruption and protection applications. Copper free aluminium is often specified for its corrosion resistance and lighter weight.

IIB+H2 碳钢喷漆 Ex d 防爆外壳 – DE8BC

Ex-tech Solution 的 DE8BC 系列 Ex d IIB 或 Ex d II B + H2 防爆外壳采用喷漆碳钢制造，也可配置为 Ex d 直接入口或 Ex de 组合用于间接入口。这非常适合室内重工业用途。

IIB+H2 Carbon steel painted Ex d explosion proof enclosures – DE8BC

The DE8BC range of Ex d IIB or Ex d II B + H2 explosion proof enclosures range from Ex-tech Solution is manufactured in painted carbon steel and can also be configured as Ex d direct entry or as an Ex de combination for indirect entry. This is perfect for indoor heavy industrial use.

IIB+H2 不锈钢 Ex d 防爆外壳 – EJB

另一种不锈钢选项包括 EJB 系列 Ex d IIB + H2 防爆外壳，专为控制、检查、信号、自动化、中断和保护用途而设计。如果需要，可以将多个外壳组装在一个带有单独或公共 Ex e/i 接线盒的框架上。外壳也可以空着交付，并附有 U 组件证书，也可以根据客户要求提供完全组装好的外壳。

不锈钢外壳通常被认为是比碳钢外壳更好的选择，因为它们更坚固、更耐用、耐腐蚀。

IIB+H2 Stainless Steel Ex d explosion proof enclosures – EJB

Another stainless steel option includes the EJB range of Ex d IIB + H2 explosion proof enclosures which are designed for control, check, signal, automation, interruption and protection use. If required, several enclosures can be assembled on a frame with separate or common Ex e/i junction boxes. The enclosures can also be delivered empty with a U component certificate or supplied fully assembled according to client demands.

Stainless steel enclosures are generally considered to be a better choice than carbon steel enclosures because they are stronger, more durable and resistant to corrosion.