DRYBER

DRYBER is a dryer system for hydrogen produced by electrolyzers. The product is able to dry H2 flow rates ranging from 0.25 kg/h up to 2.5 kg/h operating at a pressure between 30 and 35 bar. With these features, DRYBER represents a perfect-fit for combination with PEM or AEM electrolyzers up to about 120 kW of power.

Adsorption on molecular sieves

DRYBER purifies H2 from its moisture content by adsorption on molecular sieves (zeolites) packed in two columns operating alternately; when one becomes saturated (i.e. reaches its maximum State Of Charge) it is regenerated while the other comes into operation

Hydrogen purity: How many 9s?

The H2 produced by electrolysis typically occurs in a heterogeneous mixture with liquid electrolyte and once separated has a contaminant content ranging between 0.3 and 2% v/v. The main contaminants are H2O and O2; DRYBER removes only the first one. H2 4.0 is defined as Fuel Cell grade while 5.0 is the most suitable, for example, for storage in metal hydrides

ANALYSIS STATION

DRYBER product option:

Moisture content monitoring in dry H2 via dewpoint sensor (0 – 1000 ppmv)

Monitoring of O2 content in H2 via O2 detection sensor (0 – 1000 ppmv)

N.B. DRYBER does not purify H2 from the O2 content

INCOMING HYDROGEN PRE-TREATMENT

HYDROGEN COOLING

The H2 flow at the entrance to DRYBER is cooled down to a temperature of 5/10°C to reduce its moisture content by condensation. The chiller connected to the exchanger must be installed in a safe area

N.B. Hydrogen at the inlet must be free of liquid water and at temperature not exceeding 55°C

Condensate removal

The condensed liquid water entering the dryer is removed in a gas-liquid separator and expelled from the system

Two columns operating alternately

DRYBER has two adsorption columns that operate one at a time, alternately. When one reaches the maximum state of charge (SOC) it is regenerated via a heating cycle followed by a second cooling cycle.

During regeneration, a portion of hydrogen is sacrificed to remove moisture from the regenerating column. The overall efficiency in terms of hydrogen consumption is >97% (guaranteed; expected > 99%).

Three regeneration modes

NEXT START

Designed for use with DRYBER with daily cycles. Once a column is saturated, it is put into regeneration at the next start-up to ensure the max. production time H2 and prevent cycle interruption

INSTANT

Designed for use with DRYBER 24/24h. Once a column is saturated, it is immediately put into regeneration

CUSTOM

Designed for custom applications. Regeneration is initiated by the high-level control in order to take into account the operational availability of the electrolyzer and ensure the completion of the cycle