‘Green hydrogen’ is a low carbon feedstock that is increasingly being used to replace fossil-derived ‘grey hydrogen’ in refining and chemical production, or a route into hydrogen-derived products such as ammonia, methanol and synthetic fuels. The product is produced in an electrolyser stack, in which water is split down into its consistent hydrogen and oxygen.
Aside from this equipment, however, an extensive wider production system has to prepare feed water, handle the separated hydrogen, support drying and compression, and create representative gas blends before testing, metering or injection into another gas stream. In this article, we look at the ways that hydrogen blending equipment and static mixers are supporting the growth of green hydrogen production, making the process more cost-effective and efficient.
Electrolyser packages use treated water and supporting liquid circuits around the stack, separation equipment, cooling systems and control instrumentation. In alkaline electrolysis, the circulating liquid can use an electrolyte, a conductive liquid that supports the electrochemical reaction. In PEM (Proton/ proton exchange membrane) electrolysis, on the other hand, the electrolyte function is provided by a solid polymer membrane inside the stack. Deionised water is supplied to the system; at the anode, water is split into oxygen, protons and electrons. The protons pass through the membrane to the cathode, where they combine with electrons to form hydrogen.
Whenever a liquid addition enters a recirculation or conditioning line, the stream needs to become representative, or uniform, before it reaches the separator, heat exchanger, analyser or stack inlet. A static mixer can distribute that addition inside the pipe by repeatedly dividing and recombining the flow, giving you a more consistent liquid condition around the electrolyser package.
Hydrogen leaving the production area may pass through drying, compression, buffer storage, metering or test equipment before use. Some development and industrial applications require hydrogen to be premixed with nitrogen, natural gas or another compatible gas for burner trials, fuel-cell test work, calibration duties or controlled process evaluation. In these cases, the static mixer’s role is composition control before the analyser, manifold or downstream user. Gas streams entering at different pressures, velocities or concentrations can remain uneven across the pipe section when they rely only on available straight pipework. A static gas mixer creates a defined mixing path so the measured or delivered gas better reflects your intended blend.
What is hydrogen blending? In hydrogen blending, a measured proportion of hydrogen is added to a natural gas stream so that the combined gas reaches a defined hydrogen content by volume. At the injection point, the hydrogen stream has to be dispersed across the main gas flow before the blend reaches an analyser, metering point, burner test rig or downstream process.
Hydrogen has a much lower density than natural gas, so injection velocity, nozzle position, pipe diameter, main-flow velocity and available downstream pipe length all shape how quickly the two gases become uniform across the pipe section. A poorly mixed blend can give a local composition at the measurement point rather than the actual blended condition in the line.
A static gas mixer gives the process a clearly defined mixing geometry. Fixed elements split, rotate and recombine the combined gas stream, moving material across the pipe section over a controlled length. In hydrogen blending equipment, this creates a representative gas composition before measurement, testing or onward use.
If you would like to find out more about green hydrogen production and how fixed-element mixing can support your operation, please contact one of our experts today. We can discuss how static mixers can be integrated into your water-conditioning loops, test-gas blending systems, and hydrogen/natural-gas injection points to deliver consistent stream composition, improved measurement reliability, and reduced overpressure requirements. Our team can also help you assess whether a fixed-element mixing solution is suited to your plant’s pressures, flow rates, and hydrogen concentration targets, and guide you through selection, sizing, and implementation.
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