Hydrogen Applications

LESER Safety Valves for hydrogen applications

Already today, more than 600 billion cubic meters of hydrogen are produced each year worldwide for the process industry. Hydrogen is a basic material in many industries, e.g. in refineries, in ammonia production or other chemical processes. Hydrogen is produced by chemical processes or electrolysis processes using electrical energy.

In addition to these needs, the technology for using hydrogen as an energy source in combustion engines or via fuel cells is now also ready to replace petroleum products in the future.
The advantages of hydrogen as an energy carrier are among them:

Neutral CO₂-footprint: Hydrogen produced from renewable energies is a CO₂-neutral energy carrier and basic material.
Flexible energy storage: Hydrogen produced from renewable energies can be stored in liquid or gaseous form in tanks and caverns. It is distributed over the area using mobile tanks and existing gas pipelines.
Power to X: Hydrogen can be used flexibly as an energy supplier in fuel cells, fuel in combustion engines and as a coke substitute in steel production. With the addition of CO₂, it can also be used as a fuel and combustible.

Insert: Hydrogen embrittlement

Cause:
Atomic hydrogen (H) is produced on metal surfaces in contact with hydrogen, for example by electroplating. This penetrates into the metal structure and forms molecular hydrogen (H2) there again.

Effect:
The metal loses its elasticity and breaks without an expansion phase.

The LESER solution:
Austenitic steel e.g. 1.4404, which LESER uses for its plates and seat bushes in hydrogen applications as standard, is largely insensitive to hydrogen embrittlement.

LESER products for various hydrogen applications

The following product groups are preferred:

LESER recommends austenitic stainless steels such as the LESER standard materials 1.4404/316L or 1.4408/CF8M for wetted safety valve parts. These materials are insensitive to hydrogen embrittlement. Whether cast or forged material is to be used depends on the respective application conditions.

LESER Safety Valves have proven their suitability for cryogenic temperatures from -150 °C/-238 °F to absolute zero for years. For best sealing results under these conditions, the following product configuration is recommended:

Safety valve with nozzle – Product group API Type 5264
Metallic sealing surfaces - standard version
Stellited disc - LESER option code J25
Stellited nozzle - LESER option code L65

Hydrogen, whether gaseous, highly compressed or liquefied, contact us and we will find the right solution for your application. LESER tests safety valves for cryogenic applications on its own cryo test bench.

LESER reference applications

LESER covers the entire hydrogen value chain. From production in process plants, compression with high-pressure compressors, distribution in tanks, pipelines and refueling systems to consumption in mobile tanks on ships and fuel cells.

Hydrogen – from production to usage

Power generation

H2 Production

Drying & Storage

Transport

Usage

Power generation through solar energy

Solarkraftwerke — Parabolic power plant; Fresnel power plant

Solar energy generation

Solar energy can be generated by different types of systems.

Examples are:

Solar thermal power plants

Absorption of solar heat and transport via a heat transfer medium into a power plant
Conversion into electrical energy
Power plant types are parabolic troughs and Fresnel power plants, solar tower power plants are a variant
Safety valves are used in solar thermal power plants
Require high body and seat tightness due to creeping media, temperatures up to 570 °C / 1,058 °F, and pressures up to 40 bar-g / 580 psig

Photovoltaic systems

Converting solar energy directly into electrical energy via a solar cell


Type 459 Solar	Type 526

Further information on safety valves in solar power plants can be found here

Production - Types of electrolysis

PEM Electrolysis

The principle

"Proton Exchange Membrane" (PEM) electrolysis uses a solid polymer electrolyte, a proton exchange membrane, which is washed around by water. When electrical voltage is applied to the membrane, H+ hydrogen ions migrate through the membrane. This produces hydrogen at the cathode and oxygen at the anode.

Use of safety valves

Electrolysis produces hydrogen in a gaseous state.
The nominal outlet pressure is 5 bar-g. For overpressure protection the safety valves have a set pressure of 6 bar-g. The entire system consists of several modules. Each individual module has only a small to medium output. The modules are individually protected, mostly with safety valves from the Compact Performance series.


Type 437	Type 459

Alkaline Electrolysis

The principle

Alkaline electrolysis has metal electrodes that are immersed in an alkaline, aqueous solution and separated by a permeable membrane. By applying electrical current, oxygen is produced at the anode and hydrogen at the cathode. An up to 40 % potassium hydroxide (KOH) solution is split. The operating temperature of these industrial plants is sometimes over
80 °C.

Use of safety valves

The operating pressures for alkaline electrolysis are up to 34 bar-g. Overpressure protection is provided at 36 bar-g. This means that the operating and set pressures are very close to each other, as this gap is usually 20% for liquids. Therefore, pilot-operated safety valves Type 821 are increasingly used in addition to spring-loaded safety valves Type 441. Advantages:

Low closing pressure difference of max. 7%.
Modulating effect reduces the maximum amount of hydrogen discharged in case of response. This reduces the design effort for blow-off systems.


Type 441	Type 821

SOEC Electrolysis

The principle

Solid oxide electrolyser cells (SOEC), operate at temperatures between approx. 500 and 850 °C. The general function of the electrolytic cell is to split water in the form of steam into pure H2 and O2. Steam is fed into the porous cathode. When a voltage is applied, the vapor moves to the cathode-electrolyte interface and is reduced to form pure H2 and oxygen ions. The hydrogen gas then diffuses back through the cathode and is collected at its surface as hydrogen fuel gas.

Use of safety valves

Safety valves protect the cathode from impermissible overpressure. The maximum permissible operating pressure is 0.5 bar-g per stack. The LESER Type 441 offers safety from 0.1 bar-g.

Type 441

Steam Reforming

The principle

In steam reforming, natural gas, LPG or naphtha is converted into CO2 and H2. First, the input material is desulfurized and then steam is added. The mixture is passed through a catalyst. This produces a synthesis gas from H2, CO, CO2, H2O, and CH4.
The proportions of the molecules are shifted by a reaction to H2 and CO2. The separation of the two components takes place at a molecular sieve. When the system collects and stores the CO2, the hydrogen produced is "blue".

Use of safety valves

Safety valves protect the steam boilers as well as the input and output materials. Overpressure protection for the hydrogen can reach up to
51 bar-g.


Type 526	Type 447

Drying & Storage

Drying

The principle

Depending on how the hydrogen is produced, drying is necessary before further processing or transport. Without drying, moisture would condense and freeze during compression or cooling.

Use of safety valves

Safety valves protect the drying system from impermissible overpressure. All safety valves used are made of austenitic stainless steel because it is resistant to hydrogen embrittlement.


Type 437	Type 459

Storage

The principle

Hydrogen is stored either in liquid form at pressures up to 70 bar-g or in gaseous form at pressures of 200 bar-g and above.
Transcritical storage is a possible innovation for higher energy density. Here, gaseous hydrogen is stored at -240 °C and upwards of 300 bar-g.

Use of safety valves

Safety valves protect the storage tanks from impermissible overpressure. For liquid hydrogen, all safety valves used are made of austenitic stainless steel. At temperatures of -253 °C, some steels tend to become brittle - austenitic stainless steels such as 1.4404 / SA-479 316L or 1.4408 / SA-351 CF8M are suitable for these temperatures.
Safety valves used:
Type 437 up to 70 bar-g
Type 526 up to 70 bar-g
Type 459 up to 10 bar-g
If the hydrogen is stored in a gaseous state, the outlet can be made of steel. Hydrogen is only present in the outlet of the safety valve when it discharges, i.e. for a short time. Safety valves used:
Type 459 up to 352 bar-g


Type 437	Type 459	Type 526

Transport

Transport options

Hydrogen in the liquid state can be transported efficiently by train or lorry, even in small quantities, and distributed decentrally. In its gaseous state, hydrogen can be individually transported under pressure by truck. However, only in small quantities. Pipelines are used to transport large quantities of hydrogen. One example is the central German chemical triangle around Bitterfeld, Schkopau, and Leuna. The 3.6 billion m³ of hydrogen required annually are transported via various hydrogen pipelines of a combined length of 150 km.

Use of safety valves

The transport containers are protected against thermal expansion, e.g. by solar radiation. Due to the low power capacity required, the Compact Performance product group with types 437 or 459 is usually used. The compressors of the pipeline systems, which generate the pressure required for transport, can be safeguarded by type 526.


Type 437	Type 459	Type 526

Usage of hydrogen - industrial examples

Synthetic fuels

Production

Synthetic fuels can be produced from hydrogen and atmospheric carbon dioxide. This means that they differ from conventional fuels in terms of the production process and the resulting change in chemical structure. Through this process, no further CO2 is emitted into the atmosphere.

Use of safety valves

With the pilot-operated safety valves Type 811, applications can be protected close to the operating pressure. Specifically, the POSVs open at over 30 bar-g –this design allows systems to remain in the PN40 pressure class.


Type 811	Type 438	Type 459	Type 433

Hydrogen fueling stations

Hydrogen_fuling_stations_Hamburg — H2 fueling station, Hamburg Hafen City

Hydrogen fueling stations

Depending on whether hydrogen is used as a fuel in cars, trucks, or trains, the storage pressures differ. Cars are usually operated with hydrogen at up to 700 bar-g. For trucks and trains, on the other hand, the storage pressure is 350 bar-g. For refueling, a pressure drop of about 200 bar-g is required between the buffer tank and the vehicle.

Use of safety valves

Safety valves are used to protect the refueling systems at pressures of up to 1,100 bar-g. These pressures ensure sufficient distance between the refueling pressure and the set pressure. This allows the refueling process to be accelerated.


Type 437	Type 459

Industry - Chemicals

H2_Industry_Chemical — SKW Pisteritz fertilizer production

Use of hydrogen in the chemical industry

The chemical industry is currently the largest user of hydrogen, as it forms the starting point of important chemical value chains. Already today, about 12.5 billion cubic meters of hydrogen are used annually in Germany.*

Example: Ammonia production in urea plants

Urea is an important starting material for fertilizers. Hydrogen is used to produce ammonia as a precursor for Cabermat synthesis.

Use of safety valves

LESER safety valves protect all urea production processes from impermissible overpressure. For example, Type 526 safety valves protect hydrogen in the ammonia production process at up to 60 bar-g and temperatures up to 150 °C. The Cabermat synthesis itself is protected by the LESER urea safety valve.

Type 526

Industry - Plastic

Use of hydrogen in plastics

Hydrogen plays an important role in the production of plastics. For example, hydrogen is used to break hydrocarbon chains and desulfurize the process media. In this process, pressures of 200 bar-g and temperatures of up to 480 °C are generated in the cracker.

Use of safety valves

LESER safety valves protect all applications around plastics production against impermissible overpressure. In the example described, safety valves of the types 433 or 526 are used to protect the hydrogen before entering the cracker on the one hand and the feed materials on the other.


Type 433	Type 526

Industry - Steel

Transformation of the steel industry

Duisburg-Nord Landscape Park:
A piece of LESER history you can touch.

The 180-hectare disused steelworks has been used for sporting or cultural activities for over 25 years.
A unique interplay of urban nature and the industrial heritage of the Ruhr area.
LESER is part of this cultural heritage, as some of the old LESER full-lift spring safety valves of type 541 still contribute to the industrial charm of the landscape park and can be admired on site.
The LESER safety valves ensured overpressure protection around the blast furnaces.

Type 441

H2_Industry_Steel_2 — Steel mill Salzgitter

The future of steel production

German steel production currently accounts for about 30% of the country's total industrial CO2 emissions.
Convert steel production to low-CO2 and, in the long term, climate-neutral technologies, e.g. by using hydrogen instead of coking coal.
Design steel production plants in such a way that hydrogen can be used in addition to natural gas.

Use of safety valves

LESER safeguards the processes in the steel industry that have to be protected against impermissible overpressure. Safety valves protect, for example, the generation of hydrogen which is used directly in the reduction of iron ore as well as the reduction of the oxide layer in the galvanization of strip steel. The following types are used:

Type 441 at 0.5 bar-g set pressure
Type 437 at 2.5 bar-g set pressure
Type 458 at 30 bar-g set pressure


Type 437	Type 441	Type 458

Insert: The colors of hydrogen

Although hydrogen is a colorless gas, it is described and depicted in different colors. The colors symbolize the different production and power generation methods. Regardless of how hydrogen is produced, it places the identical requirements on systems and thus also on safety valves.

Green hydrogen - Hydrogen is produced by electrolysis with water and electricity from renewable sources such as solar energy, wind or water power. The production of green hydrogen is CO2-neutral.

Turquoise hydrogen - The hydrogen is produced by methane pyrolysis. The methane in the natural gas is split into hydrogen and solid carbon. Solid carbon is a granulate, which means that no CO2 is released into the atmosphere. If the energy needed for methane pyrolysis comes from renewable sources, the production is climate neutral.

Grey hydrogen - The hydrogen is produced by steam reforming fossil fuels such as natural gas, coal or oil. This produces CO2, which is released into the atmosphere.

Blue hydrogen - Like grey hydrogen, the hydrogen is produced by steam reforming. However, the CO2 produced is captured and stored. This hydrogen is therefore considered climate-neutral.

Yellow hydrogen - The hydrogen is produced by electrolysis. The electricity required comes from the normal electricity mix, i.e. a mixture of fossil and renewable energies.

Red, pink or purple hydrogen - The hydrogen is produced by electrolysis. The electricity required comes from nuclear energy.

Orange hydrogen - The hydrogen is produced by electrolysis. The required electricity comes from biomass or from waste management plants such as waste incineration plants or biogas plants.

Black hydrogen - The hydrogen is produced by electrolysis. The electricity required comes from hard coal.

White hydrogen - On the one hand, this is naturally occurring hydrogen. On the other hand, this hydrogen is a by-product of certain processes in chemical plants.

LESER Safety Valves for hydrogen applications

Insert: Hydrogen embrittlement

LESER products for various hydrogen applications

LESER reference applications

Hydrogen – from production to usage

Power generation through solar energy

Production - Types of electrolysis

PEM Electrolysis

Alkaline Electrolysis

SOEC Electrolysis

Steam Reforming

Drying & Storage

Drying

Storage

Transport

Usage of hydrogen - industrial examples

Synthetic fuels

Hydrogen fueling stations

Industry - Chemicals

Industry - Plastic

Industry - Steel

Transformation of the steel industry

Insert: The colors of hydrogen

Contact LESER

Information on H2

myLESER Account registration

LESER Safety Valves for hydrogen applications

Insert: Hydrogen embrittlement

LESER products for various hydrogen applications

LESER reference applications

Hydrogen – from production to usage

Power generation through solar energy

Production - Types of electrolysis

PEM Electrolysis

Alkaline Electrolysis

SOEC Electrolysis

Steam Reforming

Drying & Storage

Drying

Storage

Transport

Usage of hydrogen - industrial examples

Synthetic fuels

Hydrogen fueling stations

Industry - Chemicals

Industry - Plastic

Industry - Steel

Transformation of the steel industry

Insert: The colors of hydrogen

Contact LESER

Information on H2