Hydrogen Color – Gray, Blue, & Green Hydrogen – Production, Storage, & Uses
April 2, 2021 Welcome
With an ever-increasing emphasis on clean, renewable energy globally, energy producers are harnessing hydrogen as a source of power. While hydrogen has been shown to have diverse applications across the entire power generation spectrum, it must first be processed into useful forms.
This article will discuss how to synthesize different forms of hydrogen gas on an industrial scale.
What Does Hydrogen Color Mean?
Although it has been established that hydrogen is a clean form of energy, the processes by which it is synthesized are energy-intensive and can generate significant amounts of carbon. Different colors of hydrogen describe forms of the gas generated by unique processes. There are at least four different colors ascribed to hydrogen that is created using different raw materials and processes.
Hydrogen gas can be classified by the colors below.
- Brown hydrogen
- Gray hydrogen
- Blue hydrogen
- Green hydrogen
Hydrogen Production Processes
Hydrogen gas can be commercially produced using different techniques and substrates. However, most of these processes will generate significant amounts of carbon, creating an environmental concern.
Further, all hydrogen generation methods are energy-intensive. Hydrogen synthesis can be made more efficient and environmentally-friendly by incorporating decarbonization in the manufacturing process.
The key production techniques depend on steam reformation of methane, and gasification of coal.
What Is Green Hydrogen?
When grading the forms of commercially useful hydrogen, green hydrogen gas leads the pack. This form of gas is generated using renewable energy which creates clean-burning fuel without any carbon emissions as by-products of its synthesis.
The typical process for creating green hydrogen involves breaking down water into its constituent elements via electrolysis. Electricity supplied to the manufacturing process will be used to split the water into hydrogen and oxygen by causing oxidation reactions (electron loss forming oxygen) at the electrolyzer’s anode, and reduction (electron gain forming hydrogen gas) at its cathode.
Green hydrogen can be produced by three major classes of electrolysis:
- Alkaline electrolysis
- Solid oxide electrolysis
- Use of proton exchange membranes.
What Is Blue Hydrogen?
Blue hydrogen is another useful form of gas that is generated using emission-limiting technology to absorb and store most of its carbon by-products. Natural gas and other fossil fuels typically form the substrate for the manufacture of commercially useful hydrogen gas.
Incorporating carbon capture, utilization, and storage processes into the gas synthesis cycle will repurpose any generated carbon for reuse in the hydrogen manufacturing process, or store it for future use.
The process of creating blue hydrogen begins with the harnessing of substrates from natural gas or coal production which then undergo either gasification or steam methane reforming followed by carbon capture, utilization, and storage (CCUS). The end product of the process is blue hydrogen gas with low CO2 emissions resulting from production.
Blue Hydrogen vs. Green Hydrogen
The major comparison between blue and green hydrogen is in terms of carbon emissions resulting from their synthesis. While green hydrogen is generated in the most environmentally-friendly process with zero carbon emissions, CCUS technology is used to limit the emissions released when creating blue hydrogen.
What Is Gray Hydrogen?
Gray hydrogen can be generated similarly to blue hydrogen however the key difference is the absence of carbon capture, utilization, and storage. Gray hydrogen is produced from steam methane reforming processes that create substantial quantities of carbon.
How Is Hydrogen Stored?
Proper storage of the different forms of hydrogen gas is required, especially in the case of green hydrogen where a lag might occur between raw material sourcing, synthesis, and use.
Among the major storage options for larger quantities of hydrogen gas are natural geological formations: aquifers, salt, and rock caverns, as well as depleted natural gas reservoirs. Of these four storage options, salt caverns are the most suitable alternative providing optimal storage space for generated gases.
How Is Decarbonized Hydrogen Used?
Decarbonized hydrogen has three major industrial applications:
- Power generation
- Industrial heating
- Industrial feedstock
Decarbonized hydrogen provides a viable alternative to other low carbon power sources like wind and solar which might be affected by weather conditions and are therefore intermittent. Decarbonized hydrogen can be used to generate electricity in a manner that is efficient and responsive to demand.
Learn about the modular power generation process systems available from IFS and DXP today.
Many industrial processes require elevated temperatures to craft their final products. Decarbonized hydrogen can serve as a source of sufficient quantities of heat required to fire industrial kilns, drive chemical reactions, and forge metal components.
Decarbonized hydrogen can serve as an efficient fuel to drive industrial machinery and processes. Decarbonized hydrogen as a feedstock gas, can be used to replace carbon-generating fossil fuels which negatively impact the environment.
How Can IFS Improve Your Power Generation Processes?
At IFS, we provide our clients with cutting-edge technologies guaranteed to optimize their industrial manufacturing experience. We offer a broad range of renewable energy processing solutions that will improve your power generation processes. These solutions include:
- Biogas Pre-Treatment Skids
- Biomethane Capture System
- Chemical Injection Pumps and Systems
- Biodiesel Slurry Pumps
- Bioethanol Pumps and Systems
- Biofuel Plant Heat Exchangers
- Gas Pressure Regulations and Controls
- Fuel Gas Conditioning
- Particle Filtration Systems
- Balance of Plant Equipment
- Plant Ammonia Handling for NOx Emission Control
Contact DXP online today to learn more about the products, and services we offer.