Oil well Stimulation con't



Hydraulic fracturing
 


hydraulic fracturing
has been and will remain, one of the primary engineering tools for improving well productivity. This is achieved by
placing a conductive channel through near wellbore


damage, bypassing this crucial zone




extending the channel to a significant depth into
the reservoir to further increase productivity
placing the channel such that fluid flow in the reservoir is altered


Proper treatment design is thus tied to several disciplines
production engineering
rock mechanics
fluid mechanics
selection of optimum materials
operations.



what is fracturing






If fluid is pumped into a well faster than the fluid
can escape into the formation , inevitably pressure rises,
and at some point something breaks.





Injecting fluid into formation at pressure higher than the fracturing pressure of the formation creates fractures which propagate as more fluid is injected







Methods of hydraulic fractures
Acid fracturing
Proppant fracturing


Basic reasons for hydraulic fracturing


1- increase the rate or productivity


2- improve ultimate recovery


Fracture orientation



Fracture either horizontal or vertical
pressure behavior for fracturing formation
break down pressure: the pressure required to break the formation and initiate fracture.
Propagation pressure: the pressure required to continually enlarge the fracture.
Instantaneous shut in pressure: the pressure required to hold the fracture opened.

Idealized pressure behavior during fracturing