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4 Scientific Literature Review for Establishing the Status …
Oil Refining by-Product
Technology
In oil refining facilities, hydrogen can be produced on-site from catalytic steam
reforming of naphtha (C n H 2n+2 + n H 2 O ↔ n CO + (2n + 1) H2) (Rosetti 2007),
partial oxidation and catalytic cracking. Hydrogen is also produced as by-product
of other manufacturing processes (i.e. hydrogenous off-gases) (Deng et al. 2010;
Matijaševi´ c and Petri´ c 2016; Rabiei 2012).
Cost
Depending on the volume of oil processed, the on-site hydrogen production in oil
refineries is cost-competitive with the SMR and the coal gasification.
4.2.2 The Production of Hydrogen from Renewable Energy
with the Power-to-Gas Technology
The Power-to-Gas Technology
The core of a power-to-gas system is the electrolyser (van Leeuwen and Mulder 2018). In an electrolyser, the electricity splits the water into hydrogen and
oxygen. There are three main water electrolysis technologies: the alkaline electrolysis cells (AEC), the polymer electrolyte membranes (PEMEC) and the solid
oxide (SOEC). These three technologies are covered in length in the scientific
literature (Kær, Søren Knudsen; Al Shakhshir 2016; Kwasi-Effah, Obanor, and
Aisien 2015; Schmidt et al. 2017; Shiva Kumar and Himabindu 2019; Staffell
et al. 2019).
The AEC has been in commercial use since the 1920s. This is a mature technology. The key disadvantage of this system is its inability to produce high pressure
hydrogen. The hydrogen density being low, it needs to be pressurized for transportation purpose. A compressor is needed which adds costs to the system. It
also increases the space requirement. Another disadvantage of the AEC is that it
runs on low density currents which is not adequate with some of the renewable
electricity sources.
The PEMEC is less mature than the AEC but has some interesting characteristics. It is more efficient than the AEC. The design is more compact and can
be scaled up in modules. The PEMEC can operate in part-load and in overload
conditions. The CAPEX and operating costs are however higher than for the AEC.
The SOEC is the least mature technology and it is not yet in commercial
use. The SOEC technology has a major advantage as it can operate both ways
4 Scientific Literature Review for Establishing the Status …
Oil Refining by-Product
Technology
In oil refining facilities, hydrogen can be produced on-site from catalytic steam
reforming of naphtha (C n H 2n+2 + n H 2 O ↔ n CO + (2n + 1) H2) (Rosetti 2007),
partial oxidation and catalytic cracking. Hydrogen is also produced as by-product
of other manufacturing processes (i.e. hydrogenous off-gases) (Deng et al. 2010;
Matijaševi´ c and Petri´ c 2016; Rabiei 2012).
Cost
Depending on the volume of oil processed, the on-site hydrogen production in oil
refineries is cost-competitive with the SMR and the coal gasification.
4.2.2 The Production of Hydrogen from Renewable Energy
with the Power-to-Gas Technology
The Power-to-Gas Technology
The core of a power-to-gas system is the electrolyser (van Leeuwen and Mulder 2018). In an electrolyser, the electricity splits the water into hydrogen and
oxygen. There are three main water electrolysis technologies: the alkaline electrolysis cells (AEC), the polymer electrolyte membranes (PEMEC) and the solid
oxide (SOEC). These three technologies are covered in length in the scientific
literature (Kær, Søren Knudsen; Al Shakhshir 2016; Kwasi-Effah, Obanor, and
Aisien 2015; Schmidt et al. 2017; Shiva Kumar and Himabindu 2019; Staffell
et al. 2019).
The AEC has been in commercial use since the 1920s. This is a mature technology. The key disadvantage of this system is its inability to produce high pressure
hydrogen. The hydrogen density being low, it needs to be pressurized for transportation purpose. A compressor is needed which adds costs to the system. It
also increases the space requirement. Another disadvantage of the AEC is that it
runs on low density currents which is not adequate with some of the renewable
electricity sources.
The PEMEC is less mature than the AEC but has some interesting characteristics. It is more efficient than the AEC. The design is more compact and can
be scaled up in modules. The PEMEC can operate in part-load and in overload
conditions. The CAPEX and operating costs are however higher than for the AEC.
The SOEC is the least mature technology and it is not yet in commercial
use. The SOEC technology has a major advantage as it can operate both ways