I. LITERATURE REVIEW OF OFFSHORE OIL AND GAS DRILLING
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These emissions are mainly linked to the continuous circuit of sludge brought up from the well
in the mechanical device for oil removal and centrifugation operations by vibrating screens and
centrifuges. These emissions are essentially volatile organic compounds (VOCs) which are light
hydrocarbon fractions such as carbon oxides, methane and benzene as well as certain metals such
as mercury (Mey M. 2013; Ghazi M. et al 2019).
I.4.2.2 Drilling mud discharges and their management
The solid and liquid wastes that are generated during the exploration, operation and
decommissioning stages vary in volume and nature depending on the type of oil or gas platform
and drilling.
The management of these wastes must be done according to local and international legislation to
minimize the risks and environmental impacts on the marine environment and maritime life in
general, and even on human health.
The risk of pollution linked to the multiple activities of offshore drilling and therefore the
various potential environmental impacts is considerable but at the same time depends on the
overall mode of management of this pollution on the platform. Management must be adapted to
the type of pollution and the specific behavior of the pollutants. Thus, in the case of accidental
pollution, there is urgency and the solutions provided must be faster. This is the case, for
example, of accidental spills linked to the loss of control of certain operations in the overcooking
of sludge on the surface on the platform or at depth. This risk also exists in the event of
uncontrolled discharge of drilling waste into the sea as well as during their transport to land.
During the drilling of the well, there are significant volumes of contaminated cuttings (cuttings)
by hydrocarbons and non-reusable fluids which contain toxic substances. Efforts to minimize
these releases are undertaken using a solids control system installed on the surface which allows
the de-oiling of the cuttings after their continuous passage through vibrating screens and
centrifuges, during the drilling of all sections of the well. At the end of the drilling, the waste
generated can be treated on site or sent to storage and/or treatment units on land. The treatment
processes are often stabilization-solidification (inerting) or thermal desorption, which are also
applied to onshore oil drilling discharges.
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These emissions are mainly linked to the continuous circuit of sludge brought up from the well
in the mechanical device for oil removal and centrifugation operations by vibrating screens and
centrifuges. These emissions are essentially volatile organic compounds (VOCs) which are light
hydrocarbon fractions such as carbon oxides, methane and benzene as well as certain metals such
as mercury (Mey M. 2013; Ghazi M. et al 2019).
I.4.2.2 Drilling mud discharges and their management
The solid and liquid wastes that are generated during the exploration, operation and
decommissioning stages vary in volume and nature depending on the type of oil or gas platform
and drilling.
The management of these wastes must be done according to local and international legislation to
minimize the risks and environmental impacts on the marine environment and maritime life in
general, and even on human health.
The risk of pollution linked to the multiple activities of offshore drilling and therefore the
various potential environmental impacts is considerable but at the same time depends on the
overall mode of management of this pollution on the platform. Management must be adapted to
the type of pollution and the specific behavior of the pollutants. Thus, in the case of accidental
pollution, there is urgency and the solutions provided must be faster. This is the case, for
example, of accidental spills linked to the loss of control of certain operations in the overcooking
of sludge on the surface on the platform or at depth. This risk also exists in the event of
uncontrolled discharge of drilling waste into the sea as well as during their transport to land.
During the drilling of the well, there are significant volumes of contaminated cuttings (cuttings)
by hydrocarbons and non-reusable fluids which contain toxic substances. Efforts to minimize
these releases are undertaken using a solids control system installed on the surface which allows
the de-oiling of the cuttings after their continuous passage through vibrating screens and
centrifuges, during the drilling of all sections of the well. At the end of the drilling, the waste
generated can be treated on site or sent to storage and/or treatment units on land. The treatment
processes are often stabilization-solidification (inerting) or thermal desorption, which are also
applied to onshore oil drilling discharges.