Definition

Primary Production Analysis is the specific workflow and report template on Primary Well & Reservoir Performance Indicators.

Application

understand the current status and trends of reservoir depletion against expectations
understand the current status and trends of water flood efficiency against expectations
quantitatively compare performance of different wells or different groups of wells
identify and prioritize redevelopment opportunities

Technology

PRIME analysis is built around production data against material balance and require current FDP volumetrics, PVT and SCAL models.

PRIME includes well-by-well diagnostics and gross field diagnostics, but may be extended to sector-by-sector diagnostics.

Metrics

PRIME includes the following metrics:

	Metric name	Diagnostic plots	Objectives
1	Production History Map	q_o, q_g , q_w, q_inj, VRR, P_e over STOIIP & Structure	Production Distribution Overview
2	Recovery Map	Q_o, Q_g , Q_w, Q_inj, VRR, P_e over RF & Structure	Recovery Distribution Overview
3	Production History Graphs	q_o, q_g , q_w, q_inj, Y_w, GOR, P_e , N_p, N_inj vs time	Production History Overview
4	Decline Curve Analysis	q_o1, q_liq₁, q_inj1,Y_w, GOR, VRR, P_e vs time	Production Forecast
5	Recovery Diagnostic	q_o1, q_liq₁, q_inj1, Y_w, GOR, VRR, P_e, P_em vs RF	Estimate recovery efficiency and pressure decline
6	Watercut Diagnostic	Yw, Y_wm vs q_t	Check for water balance and thief water production
7	GOR Diagnostic	GOR, GOR_m vs q_t	Check for gas balance and thief gas production
8	Injection Efficiency Diagnostics	PIR , PIR_m vs Yw	Evaluate WI efficiency
9	Well Performance Analysis	P_{wf_IPR} , P_{wf_VLP}vs q_o	Check for the optimal production/injection target
10	Productivity Index Diagnostic	J_PI, J_PIm vs dP	Check for PI dynamics

Models

Yw vs Yw_FF

(1)	$\begin{array}{l}\displaystyle \gamma_w=\frac{1}{1 + \frac{K_{ro}}{K_{rw}} * \frac{\mu_w}{\mu_o} * \frac{B_w}{B_o}}\end{array}$

IPR_o vs Pe

(2)	$\begin{array}{l}\displaystyle P_{wf}=P_e - \frac{1}{J_{PI}} q_o\end{array}$

J_PI vs dp

(3)	$\begin{array}{l}\displaystyle J_{PI}=\frac{q_o}{P_e - P_{wf}}\end{array}$

VRR vs RF

(4)	$\begin{array}{l}\displaystyle VRR=\frac{B_w \, q_{WI}}{B_w \, q_W + B_o \, q_O + B_g (q_G - R_s q_O)}=\frac{B_w \, q_{WI}}{B_w \, q_W + B_o \, q_G - B_g (Y_g - R_s) q_O}\end{array}$

PIR vs Yw

(5)	$\begin{array}{l}\displaystyle {PIR=\frac{Q_o}{Q_i};} {\qquad} {\gamma}=\frac{Q_w}{Q_w + Q_o} {\quad \Rightarrow \quad} \frac{Q_w+Q_o}{Q_w}=\frac{1}{\gamma} {\quad \Rightarrow \quad} \frac{Q_o}{Q_w}={\frac{1}{\gamma}-1} {\quad \Rightarrow \quad} \frac{Q_o}{Q_w}=\frac{1-\gamma}{\gamma}\end{array}$

IPR_w vs Pe

(6)	$\begin{array}{l}\displaystyle PI=\frac{Q}{P_e - P_{wf}} {\quad \Rightarrow \quad} P_{wf}=P_e - \frac{1}{PI}Q\end{array}$

Вывод уравнения PIR

$\begin{array}{l}\displaystyle Q_w=\frac{\gamma}{1-\gamma}{Q_o}\end{array}$

$\begin{array}{l}\displaystyle VRR=\frac{B_w Q_i}{B_w Q_w + [ B_o - B_g (GOR - R_s ) ] Q_o}=\frac{B_w Q_i}{ [ B_w \frac{\gamma}{1-\gamma} + [ B_o - B_g (GOR - R_s ) ] ] Q_o }\end{array}$

$\begin{array}{l}\displaystyle PIR=\frac{Q_o}{Q_i}={ \frac{1}{VRR} }*{ \frac{1}{ \frac{\gamma}{1-\gamma} + [ \frac{B_o}{B_w} - \frac{B_g}{B_w}(GOR - R_s) ] } }\end{array}$

$\begin{array}{l}\displaystyle PIR=\frac{Q_o}{Q_i}={ \frac{1}{VRR} }*{ \frac{1-\gamma}{ \gamma + [ \frac{B_o}{B_w} - \frac{B_g}{B_w}(GOR - R_s) ] } }\end{array}$

Diagnostic

Sample Case


Fig. 1. Decline Curve Analysis	Fig. 2. Recovery Diagnostic	Fig. 3. Pressure Diagnostic

Fig. 4. Watercut Diagnostic	Fig. 5. GOR Diagnostic	Fig. 6. Injection Efficiency Diagnostics

Fig. 7. Well Performance Analysis	Fig. 8. Productivity Index Diagnostic

Page tree

PRIME – Primary Production Analysis