I. LITERATURE REVIEW OF OFFSHORE OIL AND GAS DRILLING
26
deposit is detected thanks to the seismic data collected in the previous step, a suitable platform is
installed. This platform provides many services and functions during the drilling of the well such
as cementing, casing, injection. Other specific weather and diver services are also provided by
the platform in addition to power generators, personnel living quarters, including fire safety and
gas detection systems to prevent the risk of explosion.
The operation of drilling the well is carried out by powerful tools including the derrick and the
drill bit which makes it possible to drill the sea floor and break the rocks of the geological
formations crossed. This device makes it possible to inject fluids during the drilling of the
different sections of the well to control the pressure, cool the drill bit and raise the cuttings to the
surface.
3- Exploitation of the deposit
The entry into in the optimal production of the deposit is validated by the geophysical
investigation and the numerical modeling of the previous stage. A development plan is
established beforehand which specifies: (i) the number of wells to be drilled to optimize the
exploitation of the discovered field; (ii) the type of production platform and the cost of specific
equipment according to the conditions of the marine environment; (iii) the optimal management
method for solid and liquid discharges from drilling in order to preserve the environment and
reduce depollution costs.
The installation of specific equipment is necessary throughout the life of offshore drilling. Thus,
the first step is to install tubes or hoses that allow the hydrocarbons to rise, the flow rates of
which are controlled by a series of valves and their pressure measured by pressure gauges. The
decrease in pressure informs about the advanced age of the well after several years of operation.
The lifespan of an oil or gas operation depends on the characteristics of the marine deposit. It is
15 to 30 years on average but can reach more than 50 years in the giant fields. The end of the
exploitation of an offshore field is marked by a final stage which is the dismantling of the
platform and the routing of its structures towards the ground for a future exploitation, a recycling
or an end of life as waste concerning the parts unusable.
The drilling of sections of the well is carried out according to a defined technical program and
subject to rigorous regulatory application. The well is drilled using a drill bit and derrick with
high-pressure injection of drilling fluids whose chemical composition varies according to the
depth and the nature of the geological formations crossed.
26
deposit is detected thanks to the seismic data collected in the previous step, a suitable platform is
installed. This platform provides many services and functions during the drilling of the well such
as cementing, casing, injection. Other specific weather and diver services are also provided by
the platform in addition to power generators, personnel living quarters, including fire safety and
gas detection systems to prevent the risk of explosion.
The operation of drilling the well is carried out by powerful tools including the derrick and the
drill bit which makes it possible to drill the sea floor and break the rocks of the geological
formations crossed. This device makes it possible to inject fluids during the drilling of the
different sections of the well to control the pressure, cool the drill bit and raise the cuttings to the
surface.
3- Exploitation of the deposit
The entry into in the optimal production of the deposit is validated by the geophysical
investigation and the numerical modeling of the previous stage. A development plan is
established beforehand which specifies: (i) the number of wells to be drilled to optimize the
exploitation of the discovered field; (ii) the type of production platform and the cost of specific
equipment according to the conditions of the marine environment; (iii) the optimal management
method for solid and liquid discharges from drilling in order to preserve the environment and
reduce depollution costs.
The installation of specific equipment is necessary throughout the life of offshore drilling. Thus,
the first step is to install tubes or hoses that allow the hydrocarbons to rise, the flow rates of
which are controlled by a series of valves and their pressure measured by pressure gauges. The
decrease in pressure informs about the advanced age of the well after several years of operation.
The lifespan of an oil or gas operation depends on the characteristics of the marine deposit. It is
15 to 30 years on average but can reach more than 50 years in the giant fields. The end of the
exploitation of an offshore field is marked by a final stage which is the dismantling of the
platform and the routing of its structures towards the ground for a future exploitation, a recycling
or an end of life as waste concerning the parts unusable.
The drilling of sections of the well is carried out according to a defined technical program and
subject to rigorous regulatory application. The well is drilled using a drill bit and derrick with
high-pressure injection of drilling fluids whose chemical composition varies according to the
depth and the nature of the geological formations crossed.