Operation save the environment
Hydrogen could significantly reduce CO 2 emissions in processes such as the chemical and steel industries and refining . Sophisticated valves are needed to cope with the challenges of this medium .
Text & images by Messe Düsseldorf
Thyssenkrupp has expanded its manufacturing capacities for water electrolysis to a gigawatt scale . According to the company , the group can already put into practice complete value chains – starting with the large-scale production of hydrogen arriving at the subsequent production of sustainable commodity chemicals such as ammonia or methanol . Photo : thyssenkrupp
The energy market is facing a major transition as hydrogen will have a significant impact on the fields of electricity , heat and mobility . Hydrogen could also significantly reduce CO 2 emissions in processes of the chemical and steel industries , as well as in refineries . Sophisticated valves are needed to cope with the specific challenges of this medium . The valve industry is already on course to handle this – and the market seems to be booming . Some states are already setting the course for the use of hydrogen . Germany , for example , has already recognised its potential and formulated the National Hydrogen Strategy about two years ago , also providing subsidies . “ Flexible energy carriers are indispensable for the energy transition and open up new markets for German companies ”, explains the German Ministry of Education and Research . In taking this step , Germany is pursuing a systematic approach to thinking about the production , transport , storage , distribution and use of hydrogen – including an international dimension . Power-to-gas plants are needed to generate green hydrogen . In these plants , wind and solar energy produce hydrogen via electrolysis from electricity and water . Power-to-gas plants are already in operation in Germany , as well as in Scandinavia and other European countries such as Switzerland , Austria , France , Italy and Hungary . On a global scale , these plants are used in China , Canada and Argentina , as well as in other countries .
A demanding medium
The process is particularly challenging as electrolysis produces not only hydrogen , but also oxygen . “ Both are very demanding media , with completely different requirements for corresponding valves
and their materials ”, Hartmann Valves explains . The requirements for hydrogen valves used in power-to-gas plants are comparable to other gas applications . The right choice of materials is crucial , in particular , to avoid hydrogen embrittlement . Design-engineering measures are also vital in order to guarantee the tightness of the valves against the small-molecule hydrogen in the long term . For this reason , Hartmann Valves offers gas-tight metal-seated ball valves with long service lives , which , if required , also have multiple barriers in pressure direction to increase safety in the plant . For absolute certainty and security , material suitability tests and hydrogen emission tests are essential . “ These provide the plant operator with the additional security of being able to predict actual emissions regarding the hydrogen medium that will be used later .” Hydrogen can be stored in caverns that are hermetically sealed against the medium . Wellheads are used at the interface between above-ground plant facilities and underground storage , Hartmann Valves explains . In addition to wellheads , ball valves are used for pipelines and compressor stations .
Avoiding explosive concentration
Also the Waldemar Pruss Armaturenfabrik fully focuses on dealing with the challenges connected to hydrogen valves . A particular risk for highly loaded pressure-bearing components is ‘ hydrogen embrittlement ’; a material fatigue caused by the penetration of hydrogen into the metal lattice , which leads to the formation of cracks . The company emphasises that this is “ a risk to be taken seriously ”. Hydrogen is also the chemical π www . valve-world . net Valve World November 2022
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