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

(1)	$\begin{array}{l}\displaystyle {\rm VRR_{cum}} = \frac{B_w \, Q_{WI}}{B_w \, Q_W + B_o \, Q_O + B_g Q_G - B_g R_s Q_O}\end{array}$

(2)	$\begin{array}{l}\displaystyle {\rm VRR_{inst}} = \frac{B_w \, q_{WI}}{B_w \, q_W + B_o \, q_O + B_g (q_G - R_s Q_O)}\end{array}$

2

Recovery Map

Q_o, Q_g , Q_w, Q_inj, VRR, P_e over RF & Structure

Recovery Distribution Overview

$\begin{array}{l}\displaystyle {\rm RF} = \frac{Q_o}{V_{STOIIP}}\end{array}$

3

Production History Graphs

q_o, q_g , q_w, q_inj, Y_w, Y_g, P_e , N_p, N_inj vs time

Production History Overview

$\begin{array}{l}\displaystyle {\rm Y_w} = \frac{q_w}{q_{lis}}\end{array}$

$\begin{array}{l}\displaystyle {\rm Y_g} = \frac{q_g}{q_o}\end{array}$

$\begin{array}{l}\displaystyle q_{liq} = q_o + q_w\end{array}$

4

Decline Curve Analysis

q_o1, q_liq₁, q_inj1,Y_w, Y_g, VRR, P_e vs time

Production Forecast

5

Recovery Diagnostic

q_o1, q_liq₁, q_inj1, Y_w, Y_g, VRR, P_e, P_em vs RF

Estimate recovery efficiency and pressure decline

6

Watercut Diagnostic

Y_w, Y_wm vs q_liq

Check for water balance and thief water production

(3)	$\begin{array}{l}\displaystyle {\rm Y_w} = \frac{1}{1 + \frac{K_{ro}}{K_{rw}} \cdot \frac{\mu_w}{\mu_o} \cdot \frac{B_w}{B_o}}\end{array}$

7

GOR Diagnostic

Y_g, Y_gm vs q_o

Check for gas balance and thief gas production

8

Injection Efficiency Diagnostics

PIR , PIR_m vs Y_w

Evaluate WI efficiency

$\begin{array}{l}\displaystyle {\rm PIR} = \frac{Q_o}{Q_i}\end{array}$

(4)	$\begin{array}{l}\displaystyle {\rm PIR_m} = { \frac{1}{VRR} }*{ \frac{1-Y_w}{ Y_w + (1-Y_w) [ \frac{B_o}{B_w} - \frac{B_g}{B_w}(Y_g - R_s) ] } }\end{array}$

9

Well Performance Analysis

P_{wf_IPR} , P_{wf_VLP}vs q_o

Check for the optimal production/injection target

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

10

Productivity Index Diagnostic

J_PI, J_PIm vs dP

Check for PI dynamics

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

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

Вывод уравнения PIR

(8)	$\begin{array}{l}\displaystyle Y_w=\frac{q_q}{q_w + q_o} \rightarrow \frac{q_o}{q_w} = \frac{1-Y_w}{Y_w}\end{array}$

(9)	$\begin{array}{l}\displaystyle PIR=\frac{q_o}{q_i}\end{array}$

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

Diagnostic

Expand

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