WSSD Report FINAL! - OGP

CONTRIBUTING TO SUSTAINABLE DEVELOPMENT
Waste management
Turning yellow into green
Waste sulphur is
now converted into
agricultural
fertilizer at Statoil’s
Kalundborg refinery
in Denmark.
hydraulic pumps of the wellhead control panels. The
need for pneumatic gas drivers was eliminated.
As a result of this switch, ADCO now avoids
venting 9 million standard cubic feet of gas every day
at its 142 well sites in the Asab and Bab fields. Not only
does this do away with any safety risks associated with
gas venting, it also reduces methane (CH 4
) emissions
by 17,000 tonnes per year—75 per cent of ADCO’s
annual CH 4
emissions. Life cycle savings costs are
some $8 million.
Sulphur extracted from oil products can either be
put to practical use or emitted as air-borne waste
in the form of sulphur dioxide (SO 2
). At Statoil’s
Kalundborg refinery in Denmark, the company
decided to make the most of some 275 tonnes of
sulphur that remained every
year despite the plant’s
advanced desulphurization
facilities. Previously that
sulphur had been released to
the atmosphere in the form of
550 tonnes of SO 2
.
Instead, Statoil constructed
a large new plant, costing
some NOK 70 million, to
produce agricultural fertilizer
from the leftover sulphur.
Completed in August 2001,
the Kalundborg facility is the
first of its kind, using a patent
process to produce a liquid
called ammonium thiosulphate (ATS)—a substance
highly suitable for Danish farms. Annual output of ATS is
expected to total 15–27,000 tonnes, depending on the
types of crude and other feedstock used by the refinery.
The plant was developed, built and delivered by
Haldor Topsoe A/S, which holds the patent on the
process. Tie-in with existing installations was done by
Statoil’s own project team and the group owns and
operates the facility as an integrated part of the refinery.
Refinery residue into clean power
Anew gasification process developed by
ChevronTexaco is turning a variety of carbonbased
feedstocks—including high-sulphur, lower-value
‘bottom-of-the-barrel’ refinery residue—into a much
cleaner synthesis gas known as ‘syngas’. This gas, in
turn, can be used to produce chemicals, cleaner motor
fuels or even electricity.
This is what is happening in Italy,
where three refineries are now operating
syngas-fuelled power plants. Among
them is the Energia plant in Falconara, in
which ChevronTexaco has a 24 per cent
equity stake. This gasification plant, at a
refinery near the port of Ancona, converts
tar residue from heavy oil into 280
megawatts of electrical power, which is then sold to
Enel, the Italian state-owned electricity company.
The gasification process at the Falconara operation
has allowed the refinery to reduce production of highsulphur
fuel oil, and it significantly reduces total refinery
emissions of sulphur oxides, nitrogen oxides, particulates
and carbon monoxide. As a result, the refinery has
now reduced its emissions to a point below the limits
set by European Union directives.
The ChevronTexaco gasification process is now
being applied in similar, larger projects in France with
partners TotalFinaElf and Electricité de France. An even
larger plant is in preliminary development in Spain.
Eventually, these gasification plants could also use
refinery wastes to produce the hydrogen needed for
the proliferation of automotive fuel cells.
Gasification plants
like this may
eventually be able to
use refinery wastes to
produce the
hydrogen needed for
the proliferation of
automotive fuel cells.
By reducing refinery
emissions of sulphur
oxides, nitrogen
oxides, particulates
and carbon monoxide,
the gasification
process can help
refineries comply with
limits set by European
Union directives.
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