4.3 The Use of Fossil fuel-Based Hydrogen …
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4.3.3 The Oil Refining
In oil refineries, hydrogen is used in complex chemical processes such as
hydro-cracking, hydro-treating, and hydro-desulfurization processes enabling the
distillation of crude oil into a wide range of products. The amount of hydrogen
required for processes depend on the hydrogen content of the feed and products.
It also depends on the number of heteroatoms to be removed such as sulphur
or nitrogen. Some oil refining processes produce purge gas rich in hydrogen (byproduct). The by-product hydrogen can be treated in hydrogen recover unit (HRU)
and reused in the oil refining process (Rabiei 2012).
More stringent regulations for desulphurization has led to an increase of the
demand for hydrogen. The oil refineries are equipped with hydrogen production
units (HPU) usually consisting on SMR plant of natural gas (Brau 2013).
If the demand from the oil refinery cannot be covered by the HRU and the
HPU, merchant hydrogen is procured (EPA 2008).
4.3.4 The Manufacturing of Steel
The most utilized steel manufacturing process is the BF-BOF route. In this process, the iron ore is reduced by carbon monoxide in the blast furnace (BF). Coke
and coal are used as reduction agents. The reducing agents react with the oxygen
(BOF) to produce the carbon monoxide. The carbon monoxide reduces the iron
ore to metal iron producing CO 2 (Fe 2 O 3 + 1,5 C → 2Fe + 1,5CO 2 ; Fe 2 O 3 +
3CO → 2Fe + 3CO 2 ). The resulting of the process is molten iron, slug, and blast
furnace gases.
Another competing process is the DRI-EAF route. The DRI process consists on
the direct reduction of the iron ore by hydrogen (Fe 2 O 3 + 3H 2 → 2Fe + 3H 2 O).
The process produces water and a solid sponge iron. The solid iron sponge is
then melted by the EAF process to produce steel (Otto et al. 2017). The hydrogen
currently used in the DRI-EAF route is produced from SMR of natural gas, and
though the DRI-EAF process is less CO 2 emitting than the BF-BOF process, it is
still not carbon neutral as such (Åhman et al. 2018).
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4.3.3 The Oil Refining
In oil refineries, hydrogen is used in complex chemical processes such as
hydro-cracking, hydro-treating, and hydro-desulfurization processes enabling the
distillation of crude oil into a wide range of products. The amount of hydrogen
required for processes depend on the hydrogen content of the feed and products.
It also depends on the number of heteroatoms to be removed such as sulphur
or nitrogen. Some oil refining processes produce purge gas rich in hydrogen (byproduct). The by-product hydrogen can be treated in hydrogen recover unit (HRU)
and reused in the oil refining process (Rabiei 2012).
More stringent regulations for desulphurization has led to an increase of the
demand for hydrogen. The oil refineries are equipped with hydrogen production
units (HPU) usually consisting on SMR plant of natural gas (Brau 2013).
If the demand from the oil refinery cannot be covered by the HRU and the
HPU, merchant hydrogen is procured (EPA 2008).
4.3.4 The Manufacturing of Steel
The most utilized steel manufacturing process is the BF-BOF route. In this process, the iron ore is reduced by carbon monoxide in the blast furnace (BF). Coke
and coal are used as reduction agents. The reducing agents react with the oxygen
(BOF) to produce the carbon monoxide. The carbon monoxide reduces the iron
ore to metal iron producing CO 2 (Fe 2 O 3 + 1,5 C → 2Fe + 1,5CO 2 ; Fe 2 O 3 +
3CO → 2Fe + 3CO 2 ). The resulting of the process is molten iron, slug, and blast
furnace gases.
Another competing process is the DRI-EAF route. The DRI process consists on
the direct reduction of the iron ore by hydrogen (Fe 2 O 3 + 3H 2 → 2Fe + 3H 2 O).
The process produces water and a solid sponge iron. The solid iron sponge is
then melted by the EAF process to produce steel (Otto et al. 2017). The hydrogen
currently used in the DRI-EAF route is produced from SMR of natural gas, and
though the DRI-EAF process is less CO 2 emitting than the BF-BOF process, it is
still not carbon neutral as such (Åhman et al. 2018).