RU2301886C1 - Reservoir conductivity determination method - Google Patents

Abstract

FIELD: oil industry, particularly to develop oil reservoir and to determine water permeability of productive reservoir.

SUBSTANCE: method involves operating well in steady-state regime before hydrodynamic research performance in well; carrying-out well hydrodynamic research by pressure recovery operation; determining bottom pressure and continuing reservoir fluid influx in well after well shut-down; performing mathematical treatment of measurement results. First of all reservoir is preliminarily investigated by well interference testing or by means of filtration pressure waves and pressure conductivity factor in reservoir and reduced well radius are determined, wherein the reduced well radius takes into account hydrodynamic imperfection of well. Mathematical treatment includes plotting a curve shoving dependence of relative dimension of disturbed reservoir zone on well fluid influx affection as a function of disturbance front propagation in well. The curve is approximated by polynomial. Magnitudes of function of fluid influx affection on disturbance front propagation, relative dimension of disturbed reservoir zone and bottom pressure recovery dependence are serially calculated for each bottom pressure increase and fluid influx in well measurement. Then curve showing bottom pressure increase as a function of continuing fluid influx in well is plotted and approximated by polynomial. Conductivity coefficient in steady-state well operation regime is determined from free term of the polynomial. Conductivity coefficient corresponding to fluid influx in well with output is calculated for each output measuring. Then reservoir drawdown in steady-state regime of well operation is calculated and curve demonstrating conductivity as a function of reservoir drawdown in steady-state regime of producing well operation is plotted.

EFFECT: increased accuracy and simplicity of conductivity coefficient as a function of reservoir drawdown in producing well, decreased time and oil losses during production.

1 ex, 2 tbl, 5 dwg

Description

The invention relates to the oil industry and may find application in the development of a reservoir and the determination of the hydraulic conductivity of a reservoir.

A known method for determining the physical parameters of the formation, including lowering the liquid level in the well, recording over time the increase in the level of the liquid in the well with registration devices, plotting downhole pressure measurement graphs, flow rates of the fluid depending on the bottom hole pressure depression and study time, and determining physical parameters bottomhole formation zone, skin effect and depression to overcome it, other physical parameters associated with the parameters of the remote zone hundred / 1 /.

The disadvantages of this method / 1 / are:

- a large amount of research work in connection with the need to repeatedly lower the fluid level in the wellbore; which entails significant material and labor costs, inevitable loss of oil production due to numerous downtimes of wells;

- the problem of determining the dependence of the hydraulic conductivity of the formation on the depression at the established modes of operation of the well is not solved. This is due to the fact that when processing the measured data on bottomhole pressure and inflow in the known method / 1 /, the calculated equations of the elastic filtration mode are used, based on constant values of the filtration parameters. The dependence of hydraulic conductivity on depression on the reservoir is a consequence of non-linear effects, hence the methodological apparatus used should be based on a non-linear theory of filtration.

Closest to the invention in technical essence is a method for determining the filtration parameters of the reservoir from the initial sections of the pressure recovery curves, including operating the producing well in steady state, studying the well by the pressure recovery method, during the study, the recovery curves of bottomhole pressure (KVD) and the continuous flow (PPC) are determined ) fluid from the reservoir to the well, the found values were used to determine the hydroprovic changes according to the presented formulas the bottom of the reservoir from the time of pressure recovery. As a result, according to the hydrodynamic studies of the producing well, the method of pressure recovery determines the dependence of changes in hydraulic conductivity on the time of pressure recovery / 2 /.

The disadvantages of this method / 2 / are:

- application to create a method of a traditional model of fluid filtration in a homogeneous formation with constant hydraulic conductivity, then based on this model, the dependence of changes in the hydraulic conductivity of the formation on the time of pressure recovery is determined;

- the unreasonableness of the limitations and assumptions adopted in the basic calculation formula. As a result of unreasonable simplifications of the basic calculation formula, the determined values of the hydraulic conductivity of the formation are significantly overestimated;

the problem of determining the dependence of the reservoir’s hydraulic conductivity on the depression at established well operating conditions is not solved, since linear equations of the elastic mode were used to interpret the well research data by the pressure restoration method / 2 /, although the changes in the hydraulic conductivity correspond to non-linear filtration effects. It is necessary to use the methodological apparatus of the nonlinear theory of filtration, taking into account, first of all, the structural and mechanical properties of the reservoir system.

The invention solves the problem of increasing accuracy, reducing time, simplifying the procedure for determining the dependence of hydraulic conductivity on depression in a formation in a producing well, and reducing oil production losses.

возмущенной области пласта от функции влияния ψ(t) притока жидкости в скважину на распространение в пласте фронта возмущения, построенный график аппроксимируют полиномом, для каждого замера приращения ΔР_c(t_j) забойного давления и продолжающегося притока Q_j жидкости из пласта в скважину вычисляют последовательно величины функции влияния ψ_j притока жидкости в скважину на распространение в пласте фронта возмущения, условного размера

возмущенной области пласта, функции восстановления забойного давления

по величинам

строят график функции восстановления забойного давления

в зависимости от продолжающегося притока жидкости Q(t) из пласта в добывающую скважину, построенный график аппроксимируют полиномом, по свободному члену b_o которого определяют коэффициент гидропроводности пласта ε_о при эксплуатации скважины на установившемся режиме с дебитом Q_o, для каждого замера Q_j по найденны

м величинам

и ε_о вычисляют коэффициент гидропроводности пласта ε_j, соответствующий притоку жидкости в добывающую скважину с дебитом Q_j, при этом по найденным величинам ε_j рассчитывают депрессию ΔP_j(r_с) при установившемся режиме эксплуатации скважины с дебитом Q_j в пласте с гидропроводностью ε_j, по величинам ΔР_j(r_c), ε_j строят график зависимости гидропроводности ε=f[ΔР(r_с)] от депрессии на пласт при установившихся режимах эксплуатации добывающей скважины.The problem is solved in that in the method for determining the hydraulic conductivity of the formation, which includes operating the well in steady state before conducting a hydrodynamic study, hydrodynamic study of the well by pressure restoration, determining the bottomhole pressure and the continued flow of fluid from the formation into the well after it is stopped, mathematical processing of the measurement results, according to According to the invention, the formation is preliminarily examined by the method of hydro-listening or filtration pressure waves, the coefficient of its piezoconductivity of the formation and the reduced radius of the well r _c , taking into account its hydrodynamic imperfection, and when the measurement results are mathematically processed, a graph of the conditional size

the disturbed region of the reservoir as a function of the influence of ψ (t) the flow of fluid into the well on the propagation of the disturbance front in the reservoir, the plot is approximated by a polynomial, for each measurement of the increment ΔP _c (t _j ) of the bottomhole pressure and the continued flow of fluid from the reservoir into the well, Q _j the magnitude of the function of the influence ψ _j fluid flow into the well on the propagation of a disturbance front in the formation, the conditional size

disturbed reservoir area; bottomhole pressure recovery function

in terms of

plotting downhole pressure recovery functions

depending on the ongoing inflow of fluid Q (t) from the reservoir into the producing well, the constructed schedule is approximated by a polynomial, the free term b _{o of} which determines the coefficient of hydraulic conductivity of the reservoir ε _о when the well is operating at a steady state with a flow rate of Q _o , for each measurement Q _j by found

m values

and ε _о calculate the coefficient of hydraulic conductivity of the formation ε _j corresponding to the influx of fluid into the producing well with a flow rate of Q _j , while using the found values of ε _j calculate the depression ΔP _j (r _s ) at the established operating mode of a well with a flow rate of Q _j in a formation with hydraulic conductivity ε _j , according to the values ΔР _j (r _c ), ε _{j, a} graph of the dependence of the hydraulic conductivity ε = f [ΔР (r _s )] on the depression on the reservoir under steady-state operating conditions of the producing well is plotted.

SUMMARY OF THE INVENTION

The selection and implementation of a rational method of operating oil wells is based on information about the filtration and energy characteristics of the formation. Moreover, the operating modes of the downhole equipment used are determined mainly by the productive capabilities of the deposits. The main integral parameter characterizing the throughput of the reservoir when saturated fluid flows through it is the formation hydraulic conductivity ε:

where ε is the coefficient of hydraulic conductivity of the formation, μm ² · cm / (MPa · s); k is the permeability coefficient of the formation when the fluid flows through it, μm ² ; h is the effective thickness of the reservoir, cm; μ is the coefficient of dynamic viscosity of the fluid in reservoir conditions, MPa · s.

According to the linear theory, even a very weak disturbance (small pressure gradient) from a change in the well operating mode causes a reaction (filtering at a rate proportional to the pressure gradient) in the entire drainage area, with k, h, μ, and, consequently, the reservoir hydraulic conductivity remain unchanged throughout the process.

This is contrary to numerous fishing data. A study of geophysical and hydrodynamic methods show / 3, 4 / that the hydraulic conductivity of the formation changes significantly both with long-term development of the reservoir, and during short-term studies of the well. Studies of the inflow profiles of one layer, consisting of interlayers of different permeabilities, establish an increase in the ratio of working intervals to effective power with increasing depression, with less depression the least permeable, but the most oil-saturated interlayers did not participate at all.

A significant part of oil reservoirs is characterized by heterogeneous texture of the mineralogical composition and physical properties, even within the same rock type significant permeability fluctuations are observed. With a change in porosity in a fairly narrow range, a significant spread in permeability is mainly due to the different structure of the void space. Elements of a pore medium with reduced permeability are distinguished by a large specific surface of the rock. Here the role of surface tension, wettability and spreading is more significant, i.e., the role of phenomena occurring at the interface between a solid and a liquid. As a result, the slowdown in time of filtration to complete blockage of the pore channels due to an increase in the thickness of the colloidal films.

The influence of the structural and mechanical properties of the fluid - rock system on the interaction of the permeable medium with the saturating fluid is manifested in the form of nonlinearity between the gradient of hydrodynamic forces and the filtration rate, which is the reason for the dependence of the formation's hydraulic conductivity on the well operating mode / 3 /. One of the manifestations of non-linearity is the presence of a limiting pressure gradient, upon reaching which the speed of movement sharply slows down, up to a complete stop, while the flow is described by a nonlinear filtering law.

Hence, the reservoir hydraulic conductivity coefficient is a parameter that depends not only on the structure, properties of the reservoir and the surrounding fluid, but also on the distribution of reservoir pressure, depression on the reservoir, and reservoir pressure gradient. Consequently, the hydraulic conductivity of the formation changes not only with a change in its saturation (for example, when oil is replaced by water), but also with a change in the well operating conditions during the development of the reservoir and hydrodynamic studies. Then the formation structure is represented by a set of thin horizontal interlayers of different permeability and thickness / 3 /, the fluid flow in which obeys the nonlinear filtering law and occurs with various depressions, the pressure distribution along each vertical line is assumed hydrostatic.

With a plane-radial axisymmetric fluid flow due to well operation, the highest filtration rates in each of the working interlayers are observed on the walls of the well, and here the highest pressure gradients occur. For fluid flow into the well from the most permeable layer, an insignificant reservoir pressure gradient must be created at the bottom, but exceeding the initial shear gradient here. This initial shear gradient for the most permeable interlayer is minimal, in the remaining less permeable interlayers the initial shear gradient is greater. With an increase in the pressure gradient on the borehole wall, the flow also begins in other, less permeable interbeds, with large ultimate pressure gradients, as the new interbeds are involved in the filtration, the total hydraulic conductivity of the formation increases. So for a flat radial flow, changes in the total hydraulic conductivity of the working layers of the formation are directly related to changes in the pressure gradient on the well wall and depression.

The theoretical basis of the known methods for determining hydraulic conductivity is the linear theory of the elastic regime, which implies the linear law of filtration during unsteady pressure redistribution in the reservoir and changes in the elastic reservoir and fluid reservoirs associated with starting or stopping wells, changing their operating modes. The behavior of non-stationary processes is determined by the structure of the reservoir systems, the parameters of the reservoir and the well, which are unchanged.

The theoretical basis of the proposed method is the nonlinear theory of the elastic regime, which implies the fulfillment of the nonlinear filtration law during unsteady redistribution of pressure in the reservoir and changes in the elastic reservoir of the reservoir and fluid associated with starting or stopping wells, changing modes of their operation, while during unsteady filtration in the reservoir the hydraulic conductivity coefficient changes with a change in the pressure gradient on the well wall and depression on the formation.

The invention solves the problem of determining changes in the hydraulic conductivity of the formation from the recovery curve of bottomhole pressure (HPC) and the curve of the continued flow of fluid (PPC) into the well, obtained as a result of hydrodynamic research after it has been stopped.

The problem is solved as follows

Before conducting a hydrodynamic study in an unsteady mode, an oil producing well is operated in a steady state, with a steady flow of fluid in the reservoir, flow rate Q ₀ , bottomhole pressure P _c and depression ΔР (r _c ) = Р _pl -Р _с stabilize [here R _pl - formation pressure at the bottom of a long idle well].

To find the dependence of hydraulic conductivity on depression, the piezoelectric conductivity coefficient of the formation предварительно is previously determined in one of two ways:

when implementing the main method, the study of the deposit is carried out by the method of hydrolistening or filtering pressure waves. An oil producing well is used as a disturbing well; during hydraulic monitoring, disturbance in the formation is created by putting the oil producing well into operation with flow rate Q ₀ or stopping it after operation with flow rate Q ₀ , when creating pressure filtration waves, the amplitude of harmonic flow rate fluctuations is set to Q ₀ . The value of æ is determined by the joint interpretation of the HPC data and hydraulic listening (filtering pressure waves);

the second, auxiliary method is implemented if the study of the reservoir by the method of hydro-listening or filtering pressure waves was not carried out. In this case, approximately æ is estimated by the results of well operation at the steady state:

where æ is the piezoelectric conductivity coefficient of the formation, calculated here as a first approximation, m ² / s; R _PL - reservoir pressure at the bottom of a long idle well, MPa; P _with - stationary bottomhole pressure at a steady state well operation with a flow rate of Q ₀ , MPa; r _to - the radius of the site of the reservoir for the implemented layout of wells drained by a producing well at a steady state operating mode with a flow rate of Q ₀ , m; R _with - well radius, m; β ^* - coefficient of elastic capacity of a reservoir saturated with liquid, MPa ^-1 ; h _o - effective thickness of the reservoir, m; Q _o - the volumetric flow rate of the well at the steady state of operation to a stop, l / min or m ³ / day in reservoir conditions; α is the conversion coefficient, if the dimension | Q _o | = l / min, then α = 0.37699 · 10 ⁶ , if | Q _o | = m ³ / day, then α = 0.54287 · 10 ⁶ .

Subsequently (in the second approximation of the HPC and gearbox processing procedures), the calculated value of æ is specified.

When calculating æ according to formula (2), the initial parameters are determined by the adopted scheme of well placement (r _k ), according to the passport of the well (R _c ), when analyzing fluid, core samples and the development status of the reservoir β ^* , P _pl ), as a result of geophysical and hydrodynamic studies of the well (h _o , r _k , P _pl , P _s , Q _o ).

When conducting research using the pressure recovery method, the operation of an oil well is stopped by stopping the downhole pump or closing the gates of the fountain valves. During the study, at time t after the stop, the bottomhole pressure P _c (t) and the continued flow of fluid Q (t) from the formation into the producing well are determined using one of the following methods:

direct measurements with a downhole pressure gauge and a flow meter-flowmeter installed above the perforation interval;

indirect, calculated way to increase wellhead pressure and level in the wellbore; combined measurements using depth and wellhead manometers, soundmetric methods.

The reference point t = 0 corresponds to the moment of shutting down (stopping) the producing well. The determined bottomhole pressure P _s (t = 0) is equal to the stationary bottomhole pressure P _s during operation of the well to a stop.

Thus, during the study of the well by the method of pressure recovery at discrete points in time t after shutdown, the values are determined:

the continued flow of fluid Q (t) from the reservoir into the producing well, l / min or m ³ / day;

increments ΔP _s (t) of the bottomhole pressure P _s (t) after stopping the well above the bottomhole pressure P _s to stop, MPa:

The fluid inflow Q (t) from the formation into the well decreases (decays) in time until it is completely stopped, and the increment ΔР _с (t) grows and tends to the value of the stationary depression on the reservoir ΔР (r _с ) = Р _pl -Р _с with the steady state well operation with a flow rate of Q ₀ .

The data obtained form the initial array t _j , Q _j , ΔР _s (t _j ) at j = 0; 1, 2, ... M. An example of such an array with the results of the subsequent processing of the HPC and the checkpoint of an oil producing well by the proposed method is given in Table 1.

Based on the initial array (Table 1), the curves for the reconstruction of the bottomhole pressure ΔР _s (t) and the continued flow of fluid Q (t) from the formation into the well after its shutdown are built. An example of the construction of the HPC and the gearbox is shown in Fig. 1, where the logarithm values log t _j (t _j - in seconds) are placed on the abscissa axis; on the ordinate axis - increment of bottomhole pressure ΔP _c (t _j ), MPa, continued inflow Q _{j of} oil into the well, l / min, at time t _j after stopping. Figure 1: curve 1 - increment ΔP _s (t) bottomhole pressure P _c (t) after stopping the well above the bottomhole pressure P _s to stop; curve 2 - the ongoing inflow of Q (t) oil into the well after it stops; segment 3 - tangent to the final section of the HPC, corresponding to a flat-radial transient oil filtration in the reservoir in the absence of inflow into the well.

Before the procedure for determining changes in the hydraulic conductivity of the formation on the HPP, diagnostic methods are used, for example, using a bilogarithmic graph of pressure derivatives, the final section corresponding to plane radial transient filtration in the absence of fluid flow from the formation into the well. Next, using the tangent method (Fig. 1) to the final section of the HPC in the semilogarithmic coordinates ΔР _с (t) -lgt, corresponding to a flat-radial unsteady filtration in the absence of fluid inflow from the reservoir, the reduced well radius r _c , taking into account its hydrodynamic imperfection, is determined in one of two ways :

by the angular coefficient of the tangent to the final section of the HPC and the segment cut off by the tangent on the axis ΔР _с (t);

in terms of the angular coefficient of the tangent to the final section of the HPC and the productivity coefficient Q ₀ / ΔР (r _c ) of the producing well at the established operating mode before stopping at the HPC.

The procedure for processing HPC and PPC to determine changes in the hydraulic conductivity of the formation is as follows:

1. Assign an auxiliary array N of values of the radius R (t) of the disturbance front in the formation at the moment (from the cessation of well operation, with r _with ≤R (t) ≤r _k :

r _to - the radius of the plot of the drainage drained by the producing well at a steady state operating mode with a flow rate of Q ₀ ; r _with - the reduced radius of the well, taking into account its hydrodynamic imperfection.

Values of r _c ; R (t), r _k have the same dimension:

| r _c | = | R (t) | = | r _to | = m.

An example of an auxiliary array for processing HPC and gearbox of an oil well by the proposed method is given in table 2.

2. For each value of R _i , from the array (4) calculate the values:

functions ψ _{j of the} influence of fluid influx into the well on the propagation of a disturbance front in the formation:

возмущенной области пласта от остановки скважины:conditional size

disturbed area of the reservoir from stopping the well:

безразмерны; остальные величины в (5), (6) имеют размерности:In the formula (6), the quantities

dimensionless; the remaining quantities in (5), (6) have dimensions:

| r _c | = | R _i | = m; | ψ _i | = m ² .

заносят в соответствующие колонки табл.2.The calculated values of the functions ψ _i , logψ _i and

are entered in the corresponding columns of Table 2.

соответствующих величинам R_i при i=0, 1, 2, ...N, наносят на график: lgψ_i (R_i) - на ось абсцисс;

- на ось ординат. После помещения на график всех вычисленных значений

из табл.2 выполняют аппроксимацию точек графика

например, полиномом 6-й степени:3. Value pairs

corresponding to the values of R _i when i = 0, 1, 2, ... N, plotted on the graph: logψ _i (R _i ) - on the abscissa axis;

- on the ordinate axis. After placing all calculated values on the graph

from table 2 perform the approximation of the graph points

for example, a polynomial of the 6th degree:

полиномом 6-й степени безразмерны.where a ₆ ; a ₅ ; a ₄ ; a ₃ ; a ₂ ; a ₁ ; and ₀ are the coefficients of approximation of the graph points

6th degree polynomial is dimensionless.

возмущенной области пласта от функции влияния ψ[R(t)] притока нефти в скважину на распространение в пласте фронта возмущения представлен на фиг.2, где на оси абсцисс размещают величины логарифма lgψ_i(R_i) (размерность ψ_i(R_i) - м²), на ось ординат - безразмерные величины

Величины

рассчитывают соответственно по формулам (5), (6) для вспомогательного массива (4) радиуса R(t) фронта возмущения. На фиг.2: точки 1 - значения

соответствующие величинам R_i вспомогательного массива (4); 2 - аппроксимация зависимости

полиномом 6-й степени (7).Conditional size dependency example

perturbed region of the reservoir as a function of the influence of ψ [R (t)] oil flow into the well on the propagation of the disturbance front in the reservoir is shown in Fig. 2, where the logarithm of log ψ _i (R _i ) is placed on the abscissa axis (dimension ψ _i (R _i ) - m ² ), on the ordinate axis - dimensionless quantities

Quantities

calculated accordingly by formulas (5), (6) for the auxiliary array (4) of radius R (t) of the perturbation front. Figure 2: points 1 - values

corresponding to the values of R _i auxiliary array (4); 2 - approximation of dependence

6th degree polynomial (7).

4. Find the values of the function ψ _j corresponding to the moments t _j (Table 1). In a first approximation of the processing of HPC and gearbox, the calculation of ψ _{j is} carried out according to the formula:

for j = 0, 1, 2, ... M in the original array (Table 1).

The values in the formula (8) have dimensions:

| t _j | = c; | æ | = m ² / s; | ψ _i | = m ² .

For each determined value of ψ _j define the logarithm lgψ _j.

возмущенной области пласта от остановки скважины в момент t_j:5. The values ψ _j and lgψ _j are entered in the corresponding columns of Table 1. Each of the values of lgψ _j is then used to calculate, by approximation (7), the conditional size

disturbed area of the reservoir from stopping the well at time t _j :

where a ₆ ; a ₅ ; a ₄ ; a ₃ ; a ₂ ; a ₁ ; a ₀ - coefficients of polynomial (7) found above (figure 2); j = 0, 1, 2, ... M in the original array (Table 1).

6. For each moment t _{j of the} initial array (Table 1) with j = 0, 1, 2, ... M, the function of restoring the bottomhole pressure Ï _{j is} calculated;

- функция восстановления забойного давления в момент t_j, МПа; ΔP_c(t_j) - приращение забойного давления в момент t_j после остановки скважины над забойным давлением до остановки (табл.1), МПа;

- условный размер возмущенной области пласта от остановки скважины (табл.1) в момент t_j, вычисляют по формуле (9).Where

- function to restore bottomhole pressure at time t _j , MPa; ΔP _c (t _j ) is the increment of the bottomhole pressure at time t _j after the well stops above the bottomhole pressure until it stops (Table 1), MPa;

- the conditional size of the perturbed region of the reservoir from stopping the well (table 1) at time t _j , calculated by the formula (9).

заносят в соответствующую колонку табл.1 и используют для построения графика

Specific values

entered in the corresponding column of table 1 and used to plot

например, полиномом 6-й степени:7. Perform the approximation of the graph points

for example, a polynomial of the 6th degree:

графика полиномом 6-й степени.where b ₆ ; b ₅ , b ₄ ; b ₃ ; b ₂ ; b ₁ ; b ₀ - coefficients of approximation of points

graphics polynomial 6th degree.

If the dimension of the inflow | Q (t) | = l / min, then | b ₆ | = MPa / [l / min] ⁶ ;

| b ₅ | = MPa / [l / min] ⁵ ; | b ₄ | = MPa / [l / min] ⁴ ; | b ₃ | = MPa / [l / min] ³ ;

| b ₂ | = MPa / [l / min] ² ; | b ₁ | = MPa / [l / min]; | b ₀ | = MPa.

If | Q (t) | = m ³ / day, then | b ₆ | = MPa / [m ³ / day] ⁶ ; | b ₅ | = MPa / [m ³ / day] ⁵ ;

| b ₄ | = MPa / [m ³ / day] ⁴ ; | b ₃ | = MPa / [m ³ / day] ³ ; | b ₂ | = MPa / [m ³ / day] ² ;

| b ₁ | = MPa / [m ³ / day]; | b ₀ | = MPa.

оси ординат происходит в точке А [0; b₀] с координатами, соответственно:Intersection schedule

the ordinate axis occurs at point A [0; b ₀ ] with coordinates, respectively:

where b ₀ is the free term of polynomial (11).

в зависимости от продолжающегося притока нефти Q(t) из пласта в добывающую скважину, расчет в первом приближении. Для примера на фиг.4 приведен аналогичный график расчета функции

во втором приближении. На оси абсцисс фиг.3 и 4 помещают величины продолжающегося притока нефти Q_j, м³/сут; на оси ординат - величины функции восстановления забойного давления

МПа, в моменты времени t_j после остановки. Пересечение графика

оси ординат в точке А определяется аппроксимацией заключительного участка кривой: в первом приближении координаты точки А (0; 1,15934 МПа), во втором - А (0; 1,17510 МПа). На фиг.3, 4: кривая 1 - график

кривая 2 - аппроксимация полиномом 6-й степени заключительного участка графика

3 - точка А пересечения графиком

оси ординат.For example, figure 3 shows a graph of the function of the restoration of bottomhole pressure

depending on the ongoing inflow of oil Q (t) from the reservoir into the production well, the calculation is a first approximation. For example, figure 4 shows a similar graph for calculating the function

in the second approximation. On the abscissa axis of FIGS. 3 and 4, the values of the ongoing oil inflow Q _j , m ³ / day are placed; on the ordinate axis - the values of the downhole pressure recovery function

MPa, at time t _j after stopping. Graph intersection

the ordinate axis at point A is determined by the approximation of the final section of the curve: in the first approximation, the coordinates of point A (0; 1.15934 MPa), in the second - A (0; 1.17510 MPa). In figure 3, 4: curve 1 is a graph

curve 2 - approximation by a polynomial of the 6th degree of the final plot of the graph

3 - point A intersection schedule

ordinate axis.

8. The coefficient of hydroconductivity of the formation ε _o during well operation at a steady state with a flow rate of Q _o is determined as follows:

where ε _o is the coefficient of hydroconductivity of the formation during well operation at a steady state with a flow rate of Q _o , μm ² · cm / (MPa · s); b ₀ - free member of polynomial (11), equal to the ordinate of point A of the intersection by the graph Ï (t) of the ordinate axis, MPa; λ is the conversion coefficient, if the dimension | Q _o | = l / min, then λ = 3.76991, if | Q _o | = m ³ / day, then λ = 5.42867.

9. For each moment t _j (for j = 0, 1, 2, ... M) of the initial array (Table 1), the hydraulic conductivity coefficient ε _j corresponding to the influx of fluid into the production well with flow rate Q _j is determined by the relationship:

where ε _j is the coefficient of hydraulic conductivity of the formation, corresponding to the influx of fluid into the production well with a flow rate of Q _j , μm ² · cm / (MPa · s).

The found values of ε _j are placed in table 1.

10. Calculate the stationary depression ΔP _j (r _c ) per formation at a steady well operation with a flow rate of O _j in the formation with hydraulic conductivity ε _j at j = 0, 1, 2, ... M:

where ΔP _j (r _c ) is the stationary depression on the formation at the steady state well operation with a flow rate Q _j in the formation with hydraulic conductivity ε _j , MPa; ε _j - the coefficient of hydraulic conductivity of the formation, corresponding to the influx of fluid into the production well with a flow rate of Q _j , μm ² · cm / (MPa · s).

The values ΔP _j (r _c ) are entered in Table 1 and a graph ε _j = f [ΔP _j (r _c )] of the dependence of the hydraulic conductivity on the depression in the reservoir during steady-state well operation, an example of such a graph is shown in Fig. 5. Here, on the abscissa axis, the values of the stationary depression on the formation ΔP _j (r _c ) are placed at the established operating mode of an oil well with a flow rate Q _j in the formation with hydraulic conductivity ε _j , MPa; on the ordinate axis - coefficient ε _{j of} hydraulic conductivity of the formation, corresponding to oil flow with flow rate Q _j with depression ΔР _j (r _c ), μm ² · cm / (mPa · s). Figure 5: curve 1 - determination of ε in a first approximation; curve 2 - determination of ε in the second approximation; curve 3 - mathematical modeling of an oil well in the reservoir with a variable coefficient of hydraulic conductivity ε; point 4 - determination of ε by HPC by the tangent method after well operation with a flow rate of 14.5 m ³ / day in reservoir conditions; point 5 - determination of ε by HPC by the tangent method after well operation with a flow rate of 3.2 m ³ / day in reservoir conditions.

11. If there is no study of the reservoir by the method of hydro-listening or filtering pressure waves, and the calculated value æ, estimated in the first approximation by the formula (2), is used in the HPC and PPC processing procedure, then the formation piezoelectric conductivity coefficient is specified by the formula:

where æ is the specified coefficient of the piezoelectric conductivity of the reservoir, m ² / s; ε _o - the coefficient of hydraulic conductivity of the reservoir during well operation at a steady state with a flow rate of Q _o , is determined by the formula (13), μm ² · cm / (MPa · s); h _o - effective thickness of the reservoir, m; β ^* - coefficient of elastic capacity of a reservoir saturated with liquid, MPa ^-1 ; 10 ^-5 - conversion factor.

If the study of the reservoir by the method of hydro-listening or filtering pressure waves is absent, then the coefficient процед of the piezoconductivity of the formation, refined by formula (16), is used in the further processing procedure for HPC and PPC.

12. Recalculate the values of the function ψ _{j of the} influence of fluid influx into the well on the propagation of a disturbance front in the formation. In contrast to the first approximation of the calculation in paragraph 4, with the further implementation of the procedure for processing HPC and gearbox, the calculations ψ _j for j = 0, 1, 2, ... M are performed according to the formula:

where ψ _j is the function of the influence of fluid inflow into the well on the propagation of a disturbance front in the formation at moments t _j after stopping, m ² ; æ is the piezoelectric conductivity coefficient of the formation, m ² / s; Q _ξ - fluid flow into the wellbore at the moment t _ξ after stopping the well, where ξ = 1, 2, ... j (Q _ξ values are given in Table 1), l / min or m ³ / day; t _j is the current time after the shutdown of the well (table 1), s; t _ξ are the preceding instants of time, with ξ = 1, 2, ... j (Table 1), s; ε _j is the coefficient of hydraulic conductivity of the formation (Table 1), corresponding to the influx of fluid into the well with a flow rate of Q _j , is defined in paragraph 9 by the formula (14), μm ² · cm / (MPa · s); ε _o - the coefficient of hydraulic conductivity of the reservoir during the operation of the well with a flow rate of Q _o (table 1), defined in paragraph 8 by the formula (13).

For each value of ψ _j calculated by the formula (17), its decimal logarithm Igψ _{j is} determined.

возмущенной области по аппроксимации (9) при j=0, 1, 2, ...М (табл.1).13. The obtained values ψ (t _j ) and logψ (t _j ) are entered in the corresponding columns of Table 1 and used to re-calculate the conditional size

perturbed region by approximation (9) for j = 0, 1, 2, ... M (Table 1).

14. Repeat the above procedure for processing HPC and gearbox (Fig. 4), starting from the 6th point, in the second, third ... approximation, the obtained values of ε _j are plotted on the graph (Fig. 5) of the formation hydraulic conductivity ε = f [ ΔP (r _c )] from depression under steady-state operating conditions of a producing well. They conclude that already in the second or third approximation the necessary accuracy is achieved, while the calculation error ε is less than 4%.

Thus, the result of the above HPC and PPC processing procedure is to increase accuracy, reduce time, simplify the procedure for determining the dependence of hydraulic conductivity on the depression on the formation in production wells, and by reducing well downtime, decrease in oil production losses.

An example of a specific implementation of the method

An oil producing well with a depth of 2360 m is operated by a deep pump installation at a steady state with a flow rate of 14.5 m ³ / day anhydrous oil in reservoir conditions. For the implemented layout of wells, the radius of the drained section of the reservoir r _to = 300 m

After stopping the submersible pump, the well is studied by pressure restoration, in addition to the HPC, the reservoir is studied by hydro-listening, and the joint piezoelectric conductivity coefficient ε = 0.00208 m ² / s is determined by joint interpretation.

When researching the method of restoring pressure at discrete moments of time t after stopping by direct measurements with a borehole depth gauge and sound-measuring methods, the quantities are determined (Fig. 1):

the continued flow of oil Q (t) from the reservoir into the producing well;

increments ΔP _s (t) = P _s (t) -P _s downhole pressure P _s (t) after stopping the well above the bottomhole pressure P _s to stop.

The data obtained (HPC and PPC) form the initial array t _j , O _j , ΔР _с (t _j ), Table 1 shows the beginning of the array (j = 0, 1, 2, ... 35) for the first 175 min of the process.

Before the procedure for applying the method to the HPC in the ΔР axes _with (t) -lgt, a final section is identified that corresponds to a planar radial transient filtration in the absence of oil inflow into the well (Fig. 1). Then, using the angular coefficient of the tangent to the final section and the segment cut off by the tangent on the ΔР _с (t) axis, the reduced well radius is determined: r _c = 0.066 m.

, например, для R₃₈=1,75 м:To apply the method, an auxiliary array of values of the radius R (t) of the perturbation front is specified: 0.066 m = r _c = R ₀ ; R ₁ ; R ₂ ; R ₃ ; ... R _i ... R _N = r _k = 300 m. Table 2 shows the beginning of the array (i = 0; 1, 2, ... 38). For each value of R _i from the auxiliary array by the formulas (5), (6) calculate the values

, for example, for R ₃₈ = 1.75 m:

ψ ₃₈ = {1.75 ³ + 1.75 · 0.066 ² · [3-6 · ln (1.75 / 0.066)] - 4 · 0.066 ³ } / [12 · {1.75-

-0.066)] = 0.258867 m ² ; lgψ38 = -0.58692;

(R ₃₈ ) = 1.75 / (1.75-0.066) ln (1.75 / 0.066) -1 = 2.40618.

заносят (табл.2) в соответствующие колонки вспомогательного массива, аналогично определяют остальные величины

Values ψ ₃₈ , log ₃₈ and

are entered (Table 2) in the corresponding columns of the auxiliary array; the remaining quantities are determined similarly

lgψ₃₈=-0,58692, соответствующие R₃₈=1,75 м, наносят на график (фиг.2): lgψ₃₈ - на ось абсцисс;

- ординат. Аналогично наносят остальные величины

вспомогательного массива, выполняют аппроксимацию нанесенных точек полиномом 6-й степени (фиг.2):Values

log ₃₈ = -0.58692, corresponding to R ₃₈ = 1.75 m, plotted on the graph (figure 2): log ₃₈ - on the abscissa;

- ordinate. The remaining values are applied in the same way.

auxiliary array, perform the approximation of the applied points by a polynomial of the 6th degree (figure 2):

For each t _j from the initial array (Table 1), the quantity ψ _{j is set} , in a first approximation, the calculation of ψ _{j is} performed according to formula (8), for example, for t ₃₅ = 10500 s:

ψ ₃₅ = t ₃₅ · æ = 10500 · 0.00208 m ² = 21.84, more lgψ ₃₅ = lg 21,84 = 1,3393.

The values of ψ ₃₅ and log ₃₅ are entered in the corresponding columns of Table 1.

например, для t₃₅=10500 с:According to formula (18) for each lgψ _j, values are calculated and entered in the corresponding column of Table 1

for example, for t ₃₅ = 10500 s:

например, для t₃₅=10500 с:According to the formula (10), for each t _{j, the} values are calculated and entered in the corresponding column of Table 1

for example, for t ₃₅ = 10500 s:

в первом приближении (фиг.3). Например, координаты точки графика для t₃₅=10500 с таковы: Q₃₅=8,849 л/мин=12,74 м³/сут;

The found values are used to plot

in a first approximation (figure 3). For example, the coordinates of the graph point for t ₃₅ = 10500 s are as follows: Q ₃₅ = 8.849 l / min = 12.74 m ³ / day;

графика (фиг.3) на заключительном участке при 0<Q_j≤Q_o/5:Polynomial (11) perform the approximation of points

graph (figure 3) in the final section at 0 <Q _j ≤Q _o / 5:

оси ординат происходит в точке А [0; b₀] с координатами соответственно (фиг.3):Intersection schedule

the ordinate axis occurs at point A [0; b ₀ ] with the coordinates, respectively (figure 3):

where b ₀ is the free term of polynomial (19).

According to the formula (13), in a first approximation, the coefficient of formation hydraulic conductivity ε _o during well operation with a flow rate Q _o = 10,069 l / min is equal to:

ε ₀ = Q ₀ / (λ · b ₀ ) = 10.069 / (3.76991 · 1.15934) = 2.3039 μm ² · cm / (MPa · s).

According to formula (14), to a first approximation, the value of the formation hydraulic conductivity coefficient ε _j corresponding to the oil inflow into the production well with flow rate Q _{j is} calculated and entered into the corresponding column of Table 1, for example, for Q ₃₅ = 8.849 l / min:

According to formula (15), in a first approximation, the stationary depression ΔP _j (r _c ) is calculated and entered in the corresponding column of Table 1 to the reservoir, which corresponds to the influx of oil with flow rate Q _j into the well from the reservoir with hydraulic conductivity ε _j . For example, for Q ₃₅ = 8.849 l / min and ε ₃₅ = 2.1578 μm ² · cm / (MPa · s), the depression ΔР ₃₅ (r _c ) is equal to:

ΔP ₃₅ (r _c ) = Q ₃₅ ln (r _to / r _c ) / (λ ε ₃₅ ) =

= 8.849 · ln (300 / 0.066) / (3.76991 · 2.1578) = 9.1618 MPa.

On the basis of the results obtained (Table 1), in a first approximation, a graph is constructed ε _j = f [ΔP _j (r _c )] of the dependence of hydraulic conductivity on depression in the formation during steady-state operation of an oil well (Fig. 5). As a first approximation, the resulting graph maps the coefficient of hydraulic conductivity of the formation of a stationary depression at a steady flow of oil into the well.

With the further implementation of the procedure for processing HPC and gearbox, the second calculation of ψ _j in the second approximation for each t _{j is} performed according to the formula (17), for example, for t ₅ = 1500 s:

ψ ₅ = æ · {[Q _o -0.5 · (O ₁ + O _o )] · (t ₁ -t _o ) + [Q _o -0.5 · (Q ₂ + O ₁ )] · (t ₂ -t ₁ ) +

+ [Q _o -0.5 · (Q ₃ + Q ₂ )] · (t ₃ -t ₂ ) + [Q _o -0.5 · (Q ₄ + Q ₃ )] · (t ₄ -t ₃ ) +

+ [Q _o -0.5 · (Q ₅ + Q ₄ )] · (t ₅ -t ₄ )} / (Q _o -Q ₅ · ε _o / ε ₅ ) = 0.00208 · {[10.069-

-0.5 · (10.032 + 10.069)] · (300-0) + [10.069-0.5 · (9.995 + 10.032] · (600-300) +

+ [10.069-0.5 · (9.959 + 9.995)] · (900-600) + [10.069-0.5 · (9.922 + 9.959) →

→ · (1200-900) + [10.069-0.5 · (9.885 + 9.922)] · (1500-1200)} / →

→ / (10.069-9.885 · 2.3039 / 2.2823) = 3.178 m ² ,

from here: log ₅ = log 3,178 = 0.5021.

по аппроксимации (18) при j=0, 1, 2, ...М, например, для j=35 (табл.1):The obtained values ψ (t _j ) and logψ (t _j ) are entered in the corresponding columns of Table 1 and used for re-calculation

by approximation (18) for j = 0, 1, 2, ... M, for example, for j = 35 (Table 1):

например, для t₃₅=10500 с:According to the formula (10) for each t _{j, the} values are recalculated and entered in the corresponding column of Table 1

for example, for t ₃₅ = 10500 s:

во втором приближении (фиг.4), например, координаты точки графика для t₃₅=10500 с таковы: Q₃₅=8,845 л/мин=12,74 м³/сут;

Выполняют аппроксимацию полиномом (11) точек

графика (фиг.4) на заключительном участке при 0<Q_j≤Q_o/5:The found values are used to plot

in a second approximation (Fig. 4), for example, the coordinates of the graph point for t ₃₅ = 10500 s are as follows: Q ₃₅ = 8.845 l / min = 12.74 m ³ / day;

The approximation by polynomial (11) points

graph (figure 4) in the final section at 0 <Q _j ≤Q _o / 5:

пересекает ось ординат в точке А [0, b₀] с координатами (фиг.4) соответственно:Schedule

crosses the ordinate axis at point A [0, b ₀ ] with the coordinates (figure 4), respectively:

where b ₀ is the free term of polynomial (20).

According to the formula (13), the coefficient of hydraulic conductivity of the formation ε ₀ during well operation with a flow rate of Q _o = 10,069 l / min in the second approximation is equal to:

ε ₀ = Q _o / (λ · b ₀ ) = 10.069 / (3.76991 · 1.1751) = 2.273 μm ² · cm / (MPa · s).

According to formula (14), in a second approximation, the value of the reservoir hydraulic conductivity coefficient ε _j corresponding to the oil flow with flow rate Q _{j is} calculated and entered in the corresponding column of Table 1, for example, for Q ₃₅ = 8.849 l / min:

According to formula (15), in a second approximation, the stationary depression ΔР _j (r _c ) is calculated and recorded in the corresponding column of Table 1 to the formation corresponding to the flow of oil with flow rate Q _j into the well from the formation with hydraulic conductivity ε _j . For example, for Q ₃₅ = 8.849 l / min and ε ₃₅ = 2.1269 μm ² · cm (MPa · s), the depression ΔР ₃₅ (r _s ) is equal to:

ΔP ₃₅ (r _c ) = Q ₃₅ ln (r _to / r _c ) / (λ ε ₃₅ ) =

= 8.849 ln (300 / 0.066) / (3.76991 2.1269) = 9.2948 MPa.

Based on the results obtained (Table 1), in a second approximation, a graph is constructed ε _j = f [ΔP _j (r _c )] of the dependence of the coefficient of hydraulic conductivity on the depression in the reservoir during the operation of an oil well (Fig. 5). The resulting graph, in a second approximation, maps the coefficient of hydraulic conductivity of the depression formation at a steady flow of oil into the well.

The graph ε = f [ΔР (r _c )] calculated in the third approximation practically coincides with the graph (Fig. 5) for the second approximation.

To assess the accuracy and reliability of the dependence of the hydraulic conductivity of the formation on the depression ε = f [ΔP (r _c )] obtained by HPC and PPC by the proposed method, the graph in Fig. 5 presents the results of mathematical modeling of an oil producing well in a formation with a variable coefficient of hydraulic conductivity ε. It also gives the results of determining ε from the well pressure coefficient using the known tangent method after well operation with a production rate of 14.5 and 3.2 m ³ / day of oil under reservoir conditions.

The comparison shows that already in the second or third approximation the necessary accuracy is achieved, while the error in calculating the hydraulic conductivity of the formation in the considered range of depressions is less than 4%.

The application of the proposed method improves accuracy, reduces time and simplifies the procedure for determining the dependence of reservoir hydraulic conductivity on depression, reduces oil production losses.

Information sources

1. Application for the invention of the Russian Federation No. 93053328, class. ЕВВ 43/04, 1996

2. Methodological guidelines for determining the hydrodynamic parameters of the reservoir and reservoir pressure in the fields of the association "Nizhnevolzhskneft" // Trukhachev NS, Safronov VA et al. - Volgograd: VolgogradNIPIneft, 1977. - 24 p., prototype.

3. Diyashev R.N. Joint development of oil reservoirs. - M .: Subsoil. 1984. - 208 p.

4. Identification of the hydrodynamic model of heterogeneous formations // Donkov PV, Leonov VA et al. // Intensification of oil and gas production. Proceedings of the international technology symposium. - M .: Institute of the oil and gas business, 2003. - p.227-234.

Table 1
The source data and the results of processing the HPC and the checkpoint of an oil well of the proposed method INITIAL DATA FIRST APPROXIMATION OF HVAC AND CAT j t _j , s Q _j , l / min ΔP _c (t _j ), MPa ψ _j , m ² Lgψ _j

I _j , MPa ε _j , μm ² · cm / (MPa · s) ΔP _j (r _c ), MPa - - 0 0 10,069 0.0000 0,000 - 0.0000 0.00000 2,3039 9.7638 one 300 10,032 0.0059 0.624 -0.2048 2.8073 0.00210 2,2996 9.7462 2 600 9.995 0.0131 1,248 0.0962 3,1343 0.00419 2,2953 9,7286 3 900 9,959 0,0209 1,872 0.2723 3,3282 0.00627 2,2909 9.7110 four 1200 9,922 0.0290 2,496 0.3972 3,4666 0.00835 2.2866 9.6934 5 1500 9,885 0,0373 3,120 0.4942 3,5744 0,01043 2.2823 9.6759 6 1800 9,849 0,0458 3,744 0.5733 3.6627 0.01251 2.2780 9.6584 7 2100 9,813 0,0545 4,368 0.6403 3.7375 0.01459 2.2738 9.6410 8 2400 9,777 0.0633 4,992 0.6983 3.8024 0.01666 2.2695 9.6235 9 2700 9,741 0,0723 5,616 0.7494 3.8598 0.01872 2,2652 9.6061 10 3000 9,705 0.0813 6,240 0.7952 3,9111 0,02079 2.2610 9,5887 eleven 3300 9,669 0,0904 6,864 0.8366 3.9576 0.02285 2.2567 9.5714 12 3600 9,633 0,0996 7,488 0.8744 4,0001 0,02491 2.2525 9.5540 13 3900 9,598 0.1089 8,112 0.9091 4,0392 0,02697 2,2483 9.5367 fourteen 4200 9,562 0.1183 8,736 0.9413 4,0754 0.02902 2,2441 9,5194 fifteen 4500 9,527 0,1277 9,360 0.9713 4,1091 0,03107 2.2399 9.5021 16 4800 9,492 0.1371 9,984 0,9993 4,1407 0,03312 2,2357 9.4849 17 5100 9,457 0.1466 10,608 1,0256 4,1703 0,03516 2.2315 9.4677 eighteen 5400 9,422 0.1562 11,232 1,0505 4.1983 0,03720 2,2273 9,4505 19 5700 9,388 0.1658 11,856 1,0739 4,2248 0,03924 2.2232 9,4333 twenty 6000 9,353 0.1754 12,480 1,0962 4.2499 0.04128 2.2190 9,4162 21 6300 9,319 0.1851 13,104 1,1174 4.2738 0.04331 2,2149 9,3991 22 6600 9,284 0.1948 13,728 1,1376 4.2966 0,04534 2,2107 9.3820 23 6900 9,250 0.2046 14,352 1,1569 4.3184 0,04737 2,2066 9,3649 24 7200 9,216 0.2143 14,976 1,1754 4,3393 0,04939 2,2025 9.3478 25 7500 9,182 0.2241 15,600 1.1931 4,3593 0.05141 2.1984 9,3308 26 7800 9,148 0.2340 16,224 1,2102 4.3786 0.05343 2.1943 9,3138 27 8100 9,115 0.2438 16,848 1.2265 4.3971 0,05545 2,1902 9.2968 28 8400 9,081 0.2537 17,472 1.2423 4,4149 0,05746 2.1861 9.2799 29th 8700 9,048 0.2636 18,096 1.2576 4,4321 0,05947 2.1820 9.2629 thirty 9000 9,014 0.2735 18,720 1.2723 4,4488 0.06148 2.1780 9.2460 31 9300 8,981 0.2835 19,344 1.2865 4,4649 0.06348 2.1739 9,2291 32 9600 8,948 0.2934 19,968 1,3003 4,4805 0,06549 2.1699 9,2123 33 9900 8,915 0.3034 20,592 1,3137 4,4956 0,06749 2,1658 9,1954 34 10200 8,882 0.3134 21,216 1,3267 4,5103 0,06948 2.1618 9.1786 35 10500 8,849 0.3234 21,840 1,3393 4,5245 0,07148 2.1578 9.1618

Continuation of table 1 INITIAL DATA PROCESSING HPF AND CAT IN SECOND APPROXIMATION j t _j , s Q _j , l / min ΔP _c (t _j ), MPa ψ _j , m ² Lgψ _j

I _j , MPa ε _j , μm ² · cm / (MPa · s) ΔP _j (r _c ), MPa - - 0 0 10,069 0.0000 0,000 - 0.0000 0.00000 2.2730 9.8966 one 300 10,032 0.0059 0.636 -0.1967 2.8160 0,00209 2,2687 9.8790 2 600 9.995 0.0131 1,272 0.1045 3.1434 0.00417 2.2643 9.8614 3 900 9,959 0,0209 1,908 0.2805 3,3373 0.00625 2,2600 9.8439 four 1200 9,922 0.0290 2,543 0.4054 3,4756 0.00833 2,2557 9.8264 5 1500 9,885 0,0373 3,178 0.5021 3,5833 0,01041 2.2514 9.8089 6 1800 9,849 0,0458 3,812 0.5811 3.6714 0.01248 2.2471 9.7914 7 2100 9,813 0,0545 4,445 0.6479 3.7460 0.01455 2.2428 9.7740 8 2400 9,777 0.0633 5,078 0.7057 3.8108 0.01662 2,2385 9.7566 9 2700 9,741 0,0723 5,710 0.7567 3,8679 0.01868 2,2343 9,7392 10 3000 9,705 0.0813 6,342 0.8022 3.9190 0,02075 2,2300 9,7218 eleven 3300 9,669 0,0904 6,973 0.8434 3,9653 0.02281 2,2258 9.7045 12 3600 9,633 0,0996 7,603 0.8810 4,0075 0,02486 2.2216 9.6872 13 3900 9,598 0.1089 8,233 0.9155 4.0464 0,02692 2,2173 9.6699 fourteen 4200 9,562 0.1183 8,862 0.9475 4.0824 0,02897 2,2131 9.6526 fifteen 4500 9,527 0,1277 9,490 0.9773 4,1159 0,03102 2,2089 9,6353 16 4800 9,492 0.1371 10,118 1,0051 4.1472 0,03306 2,2047 9.6181 17 5100 9,457 0.1466 10,745 1,0312 4.1766 0,03511 2,2005 9,6009 eighteen 5400 9,422 0.1562 11,371 1,0558 4,2043 0,03715 2.1964 9.5837 19 5700 9,388 0.1658 11,997 1,0791 4,2306 0,03919 2.1922 9.5665 twenty 6000 9,353 0.1754 12,622 1,1011 4.2555 0.04122 2.1880 9,5494 21 6300 9,319 0.1851 13,246 1,1221 4.2791 0.04326 2.1839 9.5323 22 6600 9,284 0.1948 13,870 1,1421 4,3017 0,04529 2,1798 9.5152 23 6900 9,250 0.2046 14,493 1,1612 4.3232 0,04731 2,1756 9.4981 24 7200 9,216 0.2143 15,116 1,1794 4,3438 0,04934 2.1715 9.4810 25 7500 9,182 0.2241 15,737 1.1969 4.3636 0.05136 2,1674 9.4640 26 7800 9,148 0.2340 16,359 1,2137 4.3826 0.05338 2.1633 9.4470 27 8100 9,115 0.2438 16,979 1.2299 4,4009 0,05540 2,1593 9,4300 28 8400 9,081 0.2537 17,599 1,2455 4,4185 0,05742 2.1552 9.4130 29th 8700 9,048 0.2636 18,218 1,2605 4,4355 0,05943 2.1511 9.3961 thirty 9000 9,014 0.2735 18,837 1.2750 4.4518 0.06144 2.1471 9.3791 31 9300 8,981 0.2835 19,455 1.2890 4.4677 0.06344 2.1430 9.3622 32 9600 8,948 0.2934 20,072 1.3026 4.4830 0,06545 2.1390 9,3454 33 9900 8,915 0.3034 20,689 1.3157 4.4979 0,06745 2.1350 9.3285 34 10200 8,882 0.3134 21,305 1,3285 4,5123 0,06945 2,1309 9.3116 35 10500 8,849 0.3234 21,921 1,3409 4,5263 0,07145 2,1269 9.2948

table 2
Auxiliary array for processing HPC and gearbox oil wells of the proposed method j R _j , m

ψ _i , m ² Lgψ _i - - 0 0,066 0.00000 0.000000 - one 0,073 0.05125 0.000008 -5.09892 2 0,079 0.09259 0.000027 -4.56985 3 0,087 0.14448 0.000069 -4.16383 four 0,100 0.22210 0.000174 -3,76047 5 0,120 0.32853 0,000418 -3.37834 6 0.150 0.46604 0,000959 -3.01819 7 0,200 0.65472 0.002281 -2.64181 8 0.250 0.80952 0,004094 -2.38783 9 0,300 0.94119 0.006374 -2.19558 10 0.350 1,05598 0.009107 -2.04060 eleven 0.400 1,15786 0.012286 -1.91061 12 0.450 1,24952 0.015903 -1.79853 13 0,500 1,33290 0.019954 -1.69996 fourteen 0.550 1,40939 0,024438 -1.61194 fifteen 0,600 1,48008 0,029350 -1.53239 16 0.650 1,54582 0,034691 -1,45979 17 0.700 1,60725 0,040457 -1.39301 eighteen 0.750 1,66493 0,046648 -1.33117 19 0,800 1,71930 0,053263 -1.27358 twenty 0.850 1,77072 0,060301 -1,21968 21 0,900 1,81950 0.067761 -1.16902 22 0.950 1,86591 0,075643 -1.12123 23 1,000 1.91017 0.083947 -1.07599 24 1,050 1.95247 0.092672 -1.03305 25 1,100 1,99299 0,101817 -0.99218 26 1,150 2.03187 0,111382 -0.95319 27 1,200 2,06923 0,121367 -0.91590 28 1,250 2,10520 0.131772 -0.88018 29th 1,300 2,13987 0.142597 -0.84589 thirty 1,350 2.17335 0.153840 -0.81293 31 1,400 2,20570 0.165503 -0.78119 32 1,450 2,23700 0.177585 -0.75059 33 1,500 2,26733 0.190086 -0.72105 34 1,550 2.29673 0.203005 -0.6989 35 1,600 2,32527 0.216343 -0.66486 36 1,650 2,35300 0.230099 -0.63808 37 1,700 2,37995 0.244274 -0.61212 38 1,750 2,40618 0.258867 -0.58692

Claims (1)

A method for determining the hydraulic conductivity of a formation, including operating a well in steady state before conducting a hydrodynamic study, hydrodynamic study of a well by restoring pressure, determining downhole pressure and the continued flow of fluid from the formation into the well after shutting it down, mathematical processing of the measurement results, characterized in that the formation is previously examined by the method of hydraulic monitoring or filtering pressure waves, determine the coefficient χ piezoelectric formation strata and reduced well radius r _s , taking into account its hydrodynamic imperfection, and when calculating the results of measurements mathematically, a graph of the conditional size

the disturbed region of the reservoir as a function of the influence of ψ (t) the flow of fluid into the well on the propagation of the disturbance front in the reservoir, the plot is approximated by a polynomial, for each measurement of the increment ΔP _c (t _j ) of the bottomhole pressure and the continued flow of fluid from the reservoir into the well, Q _j the magnitude of the function of the influence ψ _j fluid flow into the well on the propagation of a disturbance front in the formation, the conditional size

disturbed reservoir area; bottomhole pressure recovery function

in terms of Q _j ,

plotting downhole pressure recovery functions

depending on the ongoing flow of fluid Q (t) from the formation into the well, the constructed schedule is approximated by a polynomial, the free term b _{o of} which determines the coefficient of hydraulic conductivity of the formation ε _о when the well is operating in a steady state with a flow rate of Q _o , for each measurement Q _j from the results values Ï _j and ε is calculated _on the coefficient of water permeability ε _j, corresponding to an influx of fluid into the wellbore at a flow rate Q _j, with the found values ε _j calculated depression ΔP _j (r _s) during steady state operation skva ins at a flow rate Q _j in the formation with the transmissibility ε _j, from the values of _{ΔP j (r c), ε} j plotted transmissibility ε = f [? P (r _c)], ε _j from the drawdown at steady-state conditions a production well operation .

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