Specific type of Production Analysis (PA) workflow based on correlation between injection rates history and production rate history with account of bottomhole pressure history.
In case the bottomhole pressure data is not available it is considered constant over time.
Motivation
...
Production rate in producing well depends on its productivity index
, current formation pressure LaTeX Math Inline body J
and current BHP LaTeX Math Inline body p_e
: LaTeX Math Inline body --uriencoded--p_%7Bwf%7D
LaTeX Math Block | ||||
---|---|---|---|---|
| ||||
q_1^{\uparrow}(t)=J \cdot \left( p_e(t) - p_{wf}(t) \right) |
and as such depends on completion/lift settings (defining
) and how formation pressure is maintained LaTeX Math Inline body --uriencoded--p_%7Bwf%7D(t)
over time. LaTeX Math Inline body p_e = p_e(t)
It keeps declining due to the offtakes:
LaTeX Math Block | ||||
---|---|---|---|---|
| ||||
p_e(t) = p_e[q_1^{\uparrow}(t), q_2^{\uparrow}(t), q_3^{\uparrow}(t), \dots] |
and maintained by either aquifer or Fluid Injection and in the latter case depends on injection rates:
LaTeX Math Block | ||||
---|---|---|---|---|
| ||||
p_e(t) = p_e[q_1^{\downarrow}(t),q_2^{\downarrow}(t),q_3^{\downarrow}(t),\dots ] |
The combination of
, LaTeX Math Block Reference anchor qup
and LaTeX Math Block Reference anchor peup
lead to the correlation between production rates, injection rates and bottomhole pressure variation. LaTeX Math Block Reference anchor pedown
The ultimate purpose of CRM is to correlate the long-term (few months or longer) injection rates history with production rates history and BHP history (recorded by PDG).
It is essentially based on the fact that production rate responds to changes in BHP and offset injection.
The major assumptions in
...
title | Content |
---|
...
width | 70% |
---|
Panel | ||||||||
---|---|---|---|---|---|---|---|---|
| ||||||||
|
...
width | 30% |
---|
...
In case the bottomhole pressure data is not available it is considered constant over time.
The CRM is trained over historical records of production rate, injection rates and bottomhole pressure variation.
The major assumptions in CRM model are:
- productivity index of producer stays constant in time
- dynamic drainage volume of producer is finite and constant in time (which is equivalent to PSS flow regime)
- total compressibility within the drainage volume of a given producer stays constant in time
...
Assumption 2 means that interference between producers is fairly constant in time despite the rate variations and their impact on the dynamic drainage volumes.
Goals | Objectives |
Identify and prioritise production optimisation opportunities | Generate production and formation pressure forecasts based on the bottom-hole pressure and injection rates |
Identify and prioritise redevelopment opportunities | Assess productivity index of producing wells |
Identify and prioritise surveillance candidates | Assess dynamic drainage volume around producing wells |
Quantify connectivity between injectors and producers | |
Assess water flood efficiency against expectations and / or between wells or well groups |
...
Advantages |
...
Limitations | |
Fast-track |
Does not involve full-field 3D dynamic modelling and associated assumptions
Limitations
It only models injector-producer system | |
Requires minimum input data (BHP history, fowrate history and FVF) | Requires eventful history of injection rates variations |
Robust procedure (no manual setups) | Requires productivity index of producers to stay constant |
Does not involve full-field 3D dynamic modelling and associated assumptions | Requires the drainage volumes of all producers stay the same throughout the |
modelling period | |
Only applicable for specific subset of PSS fluid flow regimes |
Technology
...
The CRM trains linear correlation between variation of production rates against variation of injection rates with account of bottom-hole pressure history records in producers.
against material balance and require current FDP volumetrics, PVT and SCAL models.
...
See Capacitance-Resistivity Model @model
Inputs | Outputs |
---|---|
Production rate history | Productivity Index for the focus producer |
Bottom-hole pressure history | Drainage volume by the focus produce producer |
Injection rate history | Share of injection going towards the focus producer |
PVT model |
Show If | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
See Also
...
Petroleum Industry / Upstream / Production / Subsurface Production / Field Study & Modelling / Production Analysis
[ Capacitance-Resistivity Model @model ]
References
...
Show If | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
| ||||||||||
|
...