Lakhasly

Optimal exploitation of underground oil and gas reserves requires maintaining high rates
of oil production. The original structure of certain hydrocarbon reservoirs does not allow the
exploitation of deposits. This is the case of shale reservoirs, compact reservoirs and reservoirs
damaged by mineral and organic deposits during oil production. This leads to a significant
reduction in the permeability and productivity of the well. This is why reservoir stimulation is
necessary, particularly by hydraulic fracturing, with the aim of improving productivity or
restoring the initial state of the rocks reservoirs, by creating a permeable drain extending as
far as possible into the formation so as to facilitate the flow of fluid towards the bottom of the
well.
The purpose of hydraulic fracturing is the placement of an optimum fracture of a certain
geometry and conductivity to allow maximum incremental production (over that of the
unstimulated well) at the lowest cost. This process combines the interactions of fluid pressure,
viscosity and leakoff characteristics with the elastic properties of the rock. Accomplishing
this, while taking into account all the presented technology, requires significant attention to
the treatment execution involving optimized completion and perforating strategies,
appropriate treatment design, control and monitoring of rate, and pressure and fluid
characteristics.
The fluid characteristics of Methanol are in some ways quite different from ge1led liquids.
Methanol have relatively low viscosities, which make them similar to linear gels. On the other
hand, they have very low particle-settling rates similar to crosslinked gels. These features
were very helpful when completing wells in low-pressure zones (depleted reservoir) which is
the case of our well study OMP-742.
The main purpose of hydraulic fracturing is to create a conductive path inside the reservoir
After a fracturing treatment a coiled tubing clean up is performed by injection of N2 to help
the oil to push the fracturing gel outside the well
However, in the case of underpressurized reservoirs the fracturing treatment risks to be not
efficient because of the absence of the high pressure for the flow back.
In addition to that the borate crosslinked gels which are known to be very damaging to the
fracture and the reservoir are mostly used especially in HMD field
-VIIISo how can the fracturing treatment be successful in such cases?
What will be the best fracturing fluid to avoid more damage and help in the flow back?
The aim of this work is to study the importance of using the conventional fluid adding
Methanol. A field application consisting of a well was presented. This final brief consists of
two parts:
➢ The theoretical part contains two chapters:
The first chapter provides general hydraulic fracturing fundamentals.
The second chapter provides the hydraulic fracturing in underpressuerized reservoir.
➢ The practical part is dedicated to the realization the hydraulic fracturing in
underpressuerized reservoir using the Methanol.