Oil displacement characteristics of the formula. Defense mechanisms of the psyche. Characteristics of basic defenses (Modern psychotechnologies of manipulation). Monitoring ongoing development

6.1.4 Method of tracking water-flooded intervals

The method consists of identifying absorbing and previously absorbing layers in injection wells using injectivity profiles and tracking them from well to well. Wherein Special attention addresses the presence of reservoir replacement intervals and intervals with deteriorated reservoir properties, which have a screening effect on the movement of fluid. In each well two groups of layers are installed:

1) which can be watered by moving along the bedding of rocks from the nearest injection wells;

2) watering of which is possible as a result of flows between individual layers or the approach of water from remote injection wells.

After establishing the probable order of watering of individual layers in each well, the available operational data is used (current oil flow rates and percentage of water, their change over time), the results of interval testing, and fluid inflow profiles, based on which a preliminary conclusion is made about the watering of the layers. Next, using the ratio of the current oil flow rate to the initial one and the current oil-saturated thickness to the initial one, the correspondence of the selected oil-saturated thickness with the current oil flow rate is checked. In this case, the reservoir properties of the flooded and remaining oil-bearing part of the formation are qualitatively taken into account and attention is paid to the amount of fluid withdrawn from the well. At low fluid withdrawals that do not correspond to potential opportunities reservoir, production data is not indicative, since the well can produce highly water-cut products, although a significant part of the reservoir remains oil-bearing.

The conclusion made on the well is verified by further tracking using data from subsequent wells, especially if they have direct data on waterflooding of the formations.

In areas where the rise of OWC occurs, it is necessary to take into account the vertical movement of water, for which you can use a graph of the relationship between the water cut of the well and the distance of the OWC from the lower perforation holes.

Thus, the method makes it possible to determine the flooded thickness of the productive object in each well, and, consequently, the picture of waterflooding of the reservoir as a whole, and facilitates the further construction of maps of the influence of injection.

The current positions of the OWC for wells, established by the methods listed above, make it possible to determine the residual oil-saturated thickness as of the date of development analysis and to construct a map of residual oil-saturated thicknesses. Remaining balance oil reserves are determined by planimetering this map, and systematically conducted studies of this kind provide an idea of the development of reserves over time.

Injection impact maps (Figure D.6), constructed for individual formations, give an idea of the structure of residual reserves, which is understood as their distribution among productive formations and deposit areas that have different geological characteristics and the degree of study and conditions for their development.

6.1.5 Method for determining residual oil reserves in the drainage zone of wells using displacement characteristics

The method is based on the use of displacement characteristics constructed for production wells. For each well in operation, as well as for wells whose operation has been discontinued over the past 5 years, displacement characteristics are constructed using actual data on oil, water and liquid production various types(according to Kambarov, Nazarov-Sipachev, Sazonov, etc.). At least 4 types of displacement characteristics must be used. Then, using the obtained displacement characteristics, oil and water production is calculated while the wells continue to operate. The calculation continues until a certain limit of well operation - this is either the well reaching a certain maximum water cut, or the well reaching a certain minimum oil flow rate. When the well reaches these limits, the calculation stops, and the accumulated oil production up to this point, starting from the date on which the analysis of the development of the oil deposit is performed, represents the remaining oil reserves in the well's drainage zone. Since the calculation is carried out according to several types of displacement characteristics, the average value for all used displacement characteristics was taken for use. If, according to one of the displacement characteristics, the calculated residual reserves differ sharply from reserves according to other characteristics, then these data are excluded from the calculation of average values. For those wells that at the time of development analysis have already reached the maximum water cut or maximum flow rate, zero residual oil reserves are recorded. Similarly, zero residual oil reserves are recorded at reservoir injection wells.

Based on these data, maps of residual oil reserves in the reservoir are constructed. These maps should be used when constructing maps of residual oil-saturated thicknesses.

6.2 Determination of the degree of impact and coverage of formations by injection

The state of production of oil reserves can be judged by the dynamics of the rate of extraction, the current oil recovery factor and the coverage of the impact of water injection on the reservoir. The recovery rate is understood as the ratio of annual oil production to initial recoverable or balance oil reserves, expressed as a percentage.

The current oil recovery factor is determined by the ratio of the accumulated amount of oil produced to balance reserves as of a certain date.

The rate of oil withdrawal and current oil recovery are analyzed over time by year of development and as of the date of analysis. These indicators are determined for the deposit as a whole and for individual areas, blocks, sections and layers of development, depending on their initial balance reserves. The data is presented in tables D.12, D.13, D.14 and D.15; the text indicates areas and layers of intensive and lagging development with an explanation of the reasons for the abnormal production of oil reserves from them.

The development of oil reserves is also characterized by the rate of selection and current oil recovery from the initial recoverable oil reserves. Balance oil reserves are used most often in an effort to eliminate errors in determining the final oil recovery factor and, consequently, recoverable oil reserves, as well as in a comparative analysis of development with other fields.

The degree of impact on the deposit can be judged by changes in flow rates and operating conditions of wells in a given area. When operating wells with stable or increasing reservoir pressure, the impact on the reservoir is quite effective. In areas where reservoir pressure decreases, the impact on the reservoir is ineffective or absent altogether.

To qualitatively assess the impact on the reservoir during the development of the injection system at individual production facilities, maps of the impact of injection can be constructed (Figure D.6). The construction of such maps, as well as the number of zones of influence of injection on them and their choice are dictated by the objectives of reservoir development.

In their physical essence, injection influence maps are close to isobar maps. At the same time, the reservoir coverage indicator under the influence of injection characterizes the conditions for the production of oil reserves in a specific area and can change over a certain period of time depending on the implementation of measures.

Injection impact maps are built on the basis of reservoir distribution maps. First of all, data on the current water injection into each injection well is plotted on the map. The download is plotted in the form of a pie chart and essentially this part of the work duplicates the construction of maps of the current state of development.

After this, zones (wells) are installed that have a hydrodynamic connection with injection wells. Based on the degree of connection with injection wells, three or more groups of reservoirs can be distinguished:

group I - collectors leading to the discharge lines, i.e. having a direct hydrodynamic connection between the exploitation zone and injection wells. During injection, the impact is well transmitted, and its increase can be achieved by increasing the volume of injected water on the same injection lines;

group II - reservoirs discovered only by production wells and not having a direct hydrodynamic connection with injection lines. In this case, it is impossible to influence the formation through the existing cutting lines and either drilling of new injection wells or transferring production wells drilled in this zone to injection are required;

group III - reservoirs discovered only by injection wells and not connected to the extraction zone. To develop their reserves, drilling of production wells is required, since such zones are essentially dead ends.

For a more reasonable identification of reservoir zones with different degrees of influence of injection, data on reservoir or bottomhole pressure, well flow rates, method of operation and other auxiliary materials are plotted on the reservoir distribution map, and it is not the absolute values that are important, but mainly in which direction (increase or decrease) their changes occurred. Only a complex of all materials makes it possible to identify with sufficient grounds different zones of influence of injection. The boundaries between zones are drawn taking into account the geological structure of the deposit and, in particular, the distribution of reservoirs of varying productivity. It is much more difficult to determine the impact of injection on productive horizons that are divided into separate isolated layers, and development objects that combine several layers. As a rule, with multi-layer and dissected objects, due to differences in the reservoir properties of different layers and for other reasons, only part of the productive thickness is exposed to injection, and the degree of this impact for each of the layers can be very different from the others.

In such conditions, in most cases, the formation pressure measured in a well or its flow rate (injectivity) cannot be used to judge the performance of individual layers and layers, since here the pressure of the layer or layer in which it is highest is usually recorded, and the flow rate is composed of the flow rates of several working layers. In such cases, the productive horizon (development object) should be considered in three dimensions, paying no less attention to the vertical component (across the section) than to the horizontal components (across the area).

For this purpose, materials from studies conducted by the method of radioactive isotopes, deep flow meters and flow meters should be used. It should be borne in mind that the method of radioactive isotopes allows mainly to trace the movement of injected water through the layers, but does not provide their injectivity, and flow metering and flow metering provide more or less reliable information with reliable separation of permeable layers and layers from each other behind the column. Since flow metering and flow metering data mainly give the distribution of the total flow rate or injectivity between perforated layers or layers, to determine the coverage of layers under the influence of injection, these data must be used in combination with other methods - radiometry, thermometry, photocolorimetry of oils, etc. It is recommended when working with materials When making measurements with debitometers-flow meters, use cartograms rather than injectivity and inflow profiles.

Due to the wide variety of geological and physical conditions and applied development systems, there cannot be universal methodological recommendations on generalization and analysis of geological and field information to assess the coverage of deposits by impact. Each specific case may require its own methodological approach. Below are some general methodological techniques for performing this work.

Depending on the degree of separation of layers and interlayers, as well as the available information about their operation, a decision is made on the number and boundaries of layers allocated for analysis and, in accordance with the instructions in Section 4.1, maps of reservoir distribution are constructed (previously constructed are used). Then all available data on the performance of formations and wells is summarized. In this case, it is often useful to divide the available data according to the degree of their reliability into several groups. The first group should include the most reliable information on wells in which only one layer is perforated. The second group includes wells in which two, three or more layers are perforated, but only one layer is working. The third group has the least reliability, which includes wells in which two or more layers operate simultaneously. Here, at the beginning, it is necessary to determine which of the perforated formations are working, which are not, and then distribute the total flow rate (injectivity) between them, using both direct methods (flow metering, flow metering) and indirect ones (comprehensive well studies, analogy in the properties of areas, selection balance and downloads, etc. - see section 5.2.2).

The methodology for constructing injection impact maps for layers of a multi-layer field is the same as for a single-layer field. It must be borne in mind that if in any section of a single-layer reservoir there is no influence of injection, then during mechanized mining its reserves are still developed in the depletion mode, and in a multi-layer reservoir, the reserves of such a section are usually not developed.

In practice, when constructing maps of the impact of injection within the three previously identified groups, three degrees of impact were distinguished. In the first group (direct connection between injection and extraction zones), zones of flowing production, mechanized production and no impact were distinguished. In the second group (there is no direct connection between the injection and extraction zones), zones of influence through the merger of adjacent formations and a zone of no connection with injection are identified. In the third group there is a zone of penetration only by injection wells and a zone of no influence on low-productivity reservoirs. All specified zones are included in Table D.14.

Identification of different zones subject to unequal influence of injection makes it possible to differentiate deposit reserves and determine reserves that are actively involved in development and those that are not covered by development under the existing system and are subject to drilling, that is, to determine the structure of oil reserves at the date of development analysis.

Improvement of development systems should follow the path of increasing the impact coverage of productive formations, eliminating zones and sections of formations that are not or are weakly affected by injection.

6.3 Analysis of the dynamics of current coverage and displacement rates

and oil recovery in the watered zone of the formation

One of the most important tasks arising when analyzing development oil fields at a later stage, is to identify the nature of the distribution of the remaining balance oil reserves within the initial oil-containing volume of the deposit.

This is necessary, first of all, for a correct assessment of the remaining recoverable oil reserves using conventional development methods and known methods of intensifying oil production.

Knowledge of the nature of the distribution of residual balance oil reserves is especially important for the effective use of so-called tertiary methods of enhanced oil recovery (physical-chemical, gas, thermal, mechanical methods - hydraulic fracturing, hydraulic fracturing).

The determination of residual oil reserves Nrem, located at the date of analysis in the oil-saturated volume Vrem, can be made using the following formulas.

The sum of the deposit volumes V rest and V start is equal to the initial oil-containing volume of the deposit V:

v = v rest +V head (6.6)

The balance of oil reserves (approximately) can be written

N = N rest + N head + Q (6.7)

N - initial balance oil reserves in the deposit;

N rest - initial balance oil reserves in the volume V rest;

N plant - residual balance oil reserves in the volume of V plant;

Q - accumulated oil production from the volume of V production.

Volume V ost can be represented as consisting of two parts:

V rest = V rest.cont + V rest.cont. (6.8)

V ost.pr - volume of the discontinuous part of the initially oil-saturated volume of the formation;

V rest.continuous - the volume of the continuous part with “moving” (subject to flooding) oil.

Consequently, N rest can be represented as the sum

N rest = N rest.cont + N rest.cont. (6.9)

The volume of the discontinuous part of the formation V ost.pr depends both on the geological structure (presence of lenses and half-lenses, dead-end zones, layering, faults, pinch-outs, etc.), and on the system of influence on the formation and the distance between production and injection wells. This volume for drilled deposits is determined by zonal maps of oil-saturated thicknesses or by calculating unproduced volumes along profiles. If there is no other data, then it is usually accepted that the volume of the discontinuous part of the formation, as well as the balance reserves in this volume, do not change during the development process, because there is no impact on this volume and oil is not extracted from it, i.e. V rest.pr = V start.pr, where: V start.pr is the initial volume of the discontinuous part of the formation.

For undrilled deposits at the initial design stage, V initial pr is determined by analogy with similar deposits or in accordance with the recommendations contained in development design manuals.

The main method for determining remaining oil reserves is the volumetric method. However, at the late stage of development, the conditions for its use become much more complicated compared to the initial conditions due to the complex configuration of the current boundary between V ost and V plant, that is, the difficulty lies in determining the current position of the waterflood front (current OWC) and the current oil-bearing contours.

As is known, when oil is displaced by water, the oil recovery coefficient is considered as the product of three coefficients

K n = K out  K out = K out  K oz  K ov (6.10)

Kout - displacement coefficient;

K coverage - coverage coefficient;

K oz - flooding coverage coefficient;

Kov - displacement coverage coefficient.

The displacement coefficient is understood as the ratio of the volume of oil displaced after prolonged, repeated washing of a rock sample to the initial oil-saturated volume. This coefficient is established based on the results of laboratory studies on rock samples and, in its physical essence, characterizes the maximum oil recovery during long-term flushing from a continuous part of the formation.

V o - volume of the rock sample;

m - porosity;

 sv,  he - saturation with bound water and residual oil, respectively;

 initial - initial oil saturation.

The flooding coverage coefficient K oz (often called the flooding coefficient) is the ratio of the volume of the washed part of the formation - V inm to the volume of the formation occupied by moving oil, i.e. continuous reservoir volume – V remaining continuous. This coefficient depends mainly on the permeability heterogeneity of the formation, the ratio of oil and water viscosities, and the degree of water cut in production wells when they are shut down. See below for methods for determining the flood coverage coefficient.

Displacement coverage coefficient K ov - (coefficient of oil loss due to formation discontinuity) is defined as the ratio of the volume (reserves) covered by the impact to the entire (initial) volume (reserves) of the formation (deposit).

(6.12)

Since one of the parts of the project document for the development of an oil and gas-oil field is the substantiation of the final oil recovery of reservoirs, the task of development analysis is to check the correctness of the selected coefficients included in the oil recovery formula, namely the coefficients of displacement of oil by water, oil by gas, gas by oil, gas by water, coefficients coverage by displacement and flooding. A clarification of the physical and hydrodynamic characteristics of displacement determined under laboratory conditions is given in Section 4.5. The following describes how to determine the current waterflood coverage and oil recovery factors.

First way. At the late stage of development of oil deposits, it is of great importance to identify areas that have already been washed with water and areas that are still occupied by oil, as well as assessing the reduction in effective oil-saturated thicknesses in oil-saturated areas as a result of the movement of OWC during development. For this purpose, a map of residual effective oil-saturated thicknesses is used, constructed as of the date of development analysis, from which residual oil reserves are determined.

Oil recovery in the watered part of the formation is determined by the following formula

(6.13)

Q n - total oil production from the flooded part of the deposit since the beginning of development;

N beginning - initial balance reserves in the waterflooded volume.

The watered part of the formation is understood as the volume (oil reserves) contained between the initial and current position of the OWC.

If maps of residual oil-saturated thicknesses are built for various dates of oil reservoir development with an interval of, for example, two to three years, then it is possible to determine a series of values of achieved oil recovery in the watered part of the formation and obtain the dynamics of this indicator during the development of an oil reservoir. The curves obtained using the described method well characterize the efficiency of production of productive formations.

Second way Determining oil recovery in the watered part of the formation is associated with the process of in-circuit flooding.

With intra-circuit flooding during the period of waterless oil production, all injected water is used to displace oil, that is, each cubic meter of injected water displaces exactly the same amount of oil from the reservoir. After water breaks through into production wells through the most permeable layers, part of the injected water passes through the washed layers.

If from total number injected water, subtract the volume of water produced along with oil from production wells located in the water-flooding zone, that is, near in-circuit wells, we obtain the amount of water that has done useful work, displacing an equal volume of oil

Q zak.eff = Q zak - Q in (6.14)

Based on data on the time of appearance of fresh water in the production wells closest to the injection wells, it is possible to approximately determine the boundary of the watering front.

As already noted, during intra-circuit flooding, a very compact displacement front is usually observed, which, at a first approximation, can be considered vertical. If there is a significant “smearing” of the displacement front, then it is advisable to determine the residual effective oil-saturated thickness using production wells working with water, similarly to the previous method.

After this, a map of the effective thickness of the watered zone of the formation is constructed. In the zone of complete watering of wells, the effective thicknesses of the watered zone are equal to the initial effective oil-saturated thicknesses. In the zone limited by the watering front and the line of complete watering of wells, lines of equal current effective thicknesses are constructed.

By measuring the volume of the watered part of the formation, it is possible to determine the balance oil reserves in the watered zone, which the injected water washed and displaced into production wells.

Knowing the watered volume of the formation and the amount of oil displaced from the formation equal to the volume of effective injection, it is possible to determine the achieved oil recovery in the watered part of the formation

(6.15)

Q zak.eff - effective injection volume;

N head - balance oil reserves in the watered part of the formation.

When using this method, it is advisable to build maps of the effective thickness of the watered part of the formation during the development process.

Third way in fact, it is a variant of the first method of determining the efficiency of production of a productive formation. Here, as in the second method, a map of the effective thickness of the watered part of the reservoir is constructed, but to calculate the achieved oil recovery and the watered part of the reservoir, the amount of oil extracted from the reservoir is used

(6.16)

Q n - total oil production from the reservoir;

N head - balance reserves in the watered part of the formation.

Here it is desirable to obtain the dynamics of the oil recovery coefficient values in the watered part of the formation. If the residual effective oil-saturated thickness of the formation cannot be determined for one reason or another, then it is advisable to determine the oil recovery in the watered zone of the formation, that is, the balance reserves in the zone between the initial position of the OWC and the conventional boundary between watered and waterless wells. Otherwise, the method for determining achieved oil recovery remains unchanged.

There is also fourth way determining oil recovery in the watered part of the formation, based on the average elevation of the current position of the OWC. Based on all available data, the arithmetic mean value of the absolute level of the current OWC on the date of analysis is determined. On the previously constructed graph of the distribution of initial balance reserves by reservoir height (Figure D.7), the mark of the average value of the current OWC is plotted and the corresponding flooded oil reserves are found. The method can be used for deposits flooded with bottom water.

6.4 Analysis of the efficiency of oil reservoir development using the method

comparison of displacement characteristics

The displacement characteristic, built for the deposit as a whole, serves as a good illustration of the efficiency of oil reservoir development; it not only shows the amount of oil recovery achieved from the formation at any time, but also shows due to the consumption of the working agent (water) for displacement, this or that oil recovery from the formation was obtained .

Currently, in the Ural-Volga region and Western Siberia there is a large number of oil deposits that are in the late or even final stages of development, according to which the corresponding displacement characteristics can be constructed. From these oil deposits, analogous deposits should be selected, and a comparison of the displacement characteristics of the analogous deposit and the analyzed field should be carried out in order to determine which of the compared deposits is developed more efficiently, and to try to find out the reasons for this.

When selecting an analogue oil reservoir, one should be guided by the proximity of the following oil reservoir parameters, which largely determine the course of the displacement characteristics:

Viscosity ratios of oil and water in reservoir conditions;

Formation permeability;

Sandiness coefficient;

Initial oil saturation of the formation;

The share of oil reserves located in the oil-water zone.

If we plot the displacement characteristic of the analyzed reservoir in semi-logarithmic coordinates on a sufficiently large scale, then most of the displacement characteristic becomes linear, and in most cases it shows kinks in the direction of decreasing or, conversely, increasing water consumption for the displacement process. It is necessary to find out the reasons that lead to the observed fractures, establishing what changes in the deposit development system, or what geological and technical activities were carried out at the deposit. The nature (direction) of the breaks will indicate whether these measures led to an increase in the efficiency of developing an oil deposit or, conversely, to a decrease in its efficiency.

To determine the technological effectiveness of an event, it is necessary to determine the basic development indicators, that is, what the indicators would be without the impact. To do this, we will consider various methods for calculating technological indicators for the development of the basic option.

These methods can be divided into two groups.

The first group includes methods based on the use of physically meaningful mathematical models of the process of oil extraction from heterogeneous formations.

The second group includes extrapolation methods, including displacement characteristics and simulation models built based on the results of multivariate analysis.

Displacement characteristics mean various dependencies between the quantities of the produced volume of liquid, oil and water. One group of characteristics establishes a relationship between the accumulated values of the specified parameters (integral characteristics). Another group of dependencies is built on the basis of current oil, water and liquid extractions (differential).

To date, various authors have proposed more than 70 characteristics of repression. The first group includes the dependencies between the accumulated withdrawals of oil, water and liquid or the dependencies between the accumulated withdrawals of well production and their water cut.

The second group characterizes changes in oil production over time, and also establishes a connection between current and accumulated oil production (decline curves). The displacement characteristics reflect the actual process of oil reserves production and the associated dynamics of product water cut during the development of heterogeneous formations in the regime of oil displacement by water. It also allows us to judge the efficiency of oil reserves production during waterflooding of development sites. Comparison of the displacement characteristics of various objects in dimensionless time allows one to compare these objects and identify the causes and factors influencing the nature of oil reserves production.

To calculate the technological efficiency from the use of the Ritin polymer-gel system, the integral displacement characteristics were used:

1. -method of S.N. Nazarov and N.V. Sipachev
2. - Kambarova G.S.

3. - Pirverdyan A.M.
4. - Kazakova A.A.
5. - Maksimova M.I.

where Qn, Ql are the accumulated production of oil and liquid, respectively, A, B are coefficients determined by statistical processing of actual data.

Using actual data on accumulated oil and liquid production for the forecast period, dependencies are constructed using these formulas. By extrapolating the resulting straight line to the forecast period, we can obtain indicators for the development of the base option. Then, comparing them with actual ones, the change in accumulated oil and liquid production is determined.

We construct a curve in the appropriate coordinates, depending on the formula. For example, if according to S.N. Nazarov and N.V. Sipachev, then in the coordinates the ratio of the accumulated liquid production to the accumulated oil production is the accumulated water production. Constants A and B are calculated automatically in MS Excel, and are displayed with the equation of the straight line. Similarly, we obtain equations for other displacement characteristics.

1. Method of Nazarov S.N. and Sipachev N.V.

A=2.1594, B=0.0035, R 2 =0.993

2. Method of Kambarov G.S.

A=285.1, B=-78195, R 2 =0.996

3. Method of Pirverdyan A.M.

A=334.4 B=-3929, R 2 =0.986

4. Method of Kazakov A.A.

A=1.7024 B=0.2094, R 2 =0.985

5. Method Maksimov M.I.

A=-67.933 B=97.461 R 2 =0.986

It should be especially noted that all displacement characteristics were obtained empirically based on generalization of field data from a limited number of fields. Many years of experience in using the proposed equations shows that each layer should have its own characteristic. In addition, in accordance with this technique, it is assumed that a linear relationship between the parameters of the equations under consideration is maintained throughout. But this condition is not met. Despite the significant shortcomings of this method for predicting technological development indicators, at present it is used more often than other methods to assess the effectiveness of stimulation of the reservoir. But since it has not yet been possible to develop objective selection criteria, therefore they take 3-4 dependencies from their entire variety and take the average forecast value for these characteristics, as was done in the calculation. Hence such differences between predicted and actual values

Having carried out calculations using displacement curves, we obtained an additional 4,732 tons of oil from source No. 303 over 3 years; according to Lysenko’s method, the increase in production is 4,412 tons per year. Measures to enhance oil recovery carried out at the Mykhpayskoye field during this time, aimed at leveling the front of oil displacement by water, allowed:

- reduce the water cut of products to an average of 95.5%;
- reduce the rate of decline in oil production and stabilize it;
- reduce the share of water in extracted products;

Increase oil production;

Also receive an additional 114,612 tons of oil.

Albina writes:

Good day!
I would like to appeal to scientific minds with a request to clarify the “truthfulness” of models (formulas) for estimating Qizvl. Specifically, this concerns the characteristics of repression.
I am familiar with 12 of the known ones (perhaps there are many more):
- Nazarov S. N. - Sipachev N. V.
- Kambarov G. S.
- Pirverdyan A. M.
- Kazakov A. A. et al.
The only problem is that the same methodology for determining recoverable reserves in various sources has many interpretations. Okay, the description, there are also many varieties of the formula, the result of calculations “with best wishes.”
For example, in one literature, the formula of Herb F.A.-Zimmerman E.H. takes into account annual water and oil withdrawals, in another - they are accumulated. The same story with the method of Movmyg G.T. and with the others...
Maybe someone has an RD or something like that. approved...? Please help me sort out this mess.

Good afternoon!!!
There is nothing complicated about the characteristics of preemption.
Firstly, you need to understand that there are only 2 main reservoir models that make it possible to obtain model
displacement characteristics:
1) piston model of a multilayer reservoir: Arps, Dykstra-Parson, etc.
2) Buckley-Leverett models, log(WOR)/KIN, etc.

The difference is that in the first case the fractional flow function
1) get using
permeability distribution density function, then the general form of the equations will be: SIF = f(F(k)), OBW = f(F(k)), Vprok = f(F(k)).
These equations can be combined i.e. 1 and 2 or 1 and 3. Then in different options different dependencies will be obtained (either on the current flow rate or on the accumulated production).

2) originally introduced in the Buckley-Leverrett theory.
And for any phase and mobility relationships, it is possible to obtain relationships of the form: SIF = f(s), OBW = f(s), Vprok = f(s).
And for each phase these relationships will be different => hence their abundance.......... For example (X-cut method with Corey functions)

The coolest thing is:
1) that these functions can be written separately for each well (drained volume). Then you can
interfere with their automatic adaptation (the number of control parameters is small => the adaptation speed is high)
There is a “downhole” model that gives an optimally accurate forecast (if, as usual for an entire field, the accuracy is low)

2) I myself made a forecast for a number of deposits and you can’t imagine how good results are obtained in the “downhole” model. Even if there is all sorts of nonsense like GTM, the whole thing is easily modeled by introducing a new coefficient of permeability variation with
moment in time geological and technical measures => in general, in terms of speed of adaptation, even the stream line is resting.......

Disadvantages => you need to divide reserves by wells, although reserves can also be made an adaptive parameter. (And who counts them exactly? But
at the final stage, you can divide the accumulated funds proportionally.)
In general, if you have any “problems” or questions, you can contact:

1st group of field statistical methods for forecasting development indicators (displacement curves similar to the method of Nazarov S.N., Sipacheva N.V. (1972)).

One of the existing groups of methods belongs to the group of dependencies characterizing the relationship between the oil-water factor (WOR) and the accumulated production of formation fluids.

These models related to the group of methods under consideration (displacement characteristics) are presented in the form of the main characteristics of displacement stated by the authors, and in the form of characteristics slightly transformed and stated by other authors who believe that in their modification these characteristics are more adequate.

Using modified displacement characteristics, the parametric coefficients a and b are determined in different coordinates and, accordingly, the approximation results are different for the same data, but all other calculations are performed in the same way.

The methods of this group are based on the presence of a close connection between the accumulated production of oil, water and liquid, identified based on the analysis of integral production curves for a number of deposits.

Methods of Nazarov S.N., Sipacheva N.V. (1972) and Sipachev and Posevich (1980) describe the direct dependence of the growth of the water-oil factor (WOR) on the growth of water production with an increase in the water cut of the produced product. The higher the accumulated water-oil factor and the more stable and uniform the development of the studied object is, the more relevant the use of these methods is.

The method of the French Petroleum Institute (1972) stands out somewhat from this group, since the model embedded in it differs in the nature of development from the two methods considered. This model assumes the dependence of the water-oil factor, linearizing at a certain stage of development of the filtration dynamics inherent in the object under study and at the same time stabilizing the rate of decline in oil production, which is characteristic of objects with a high proportion of water content in the produced product at a later stage. However, these two trends are not related to each other in development and, accordingly, this method shows results of a slightly different nature, i.e. describes other relationships between given quantities.

2nd group of field statistical methods for forecasting development indicators (displacement curves similar to M.I. Maksimov’s method (1959)).

This group of methods describes well the majority of the objects under study. Methods Maksimov M.I. (1959) and Sazonov B.F. (1972) are very weakly, compared to other methods, especially methods of the 1st group, influenced by various types of corrections and changes in the development system on the forecast results. The methods discussed in this section can be used at earlier stages of field development, when oil extraction values from recoverable reserves reach 0.4-0.5.

However, there are objects whose description using these models is not entirely adequate. This applies to objects at a late stage of development with active work on correcting the operation of the field, for example, isolating water inflows, drilling sidetracks, introducing enhanced oil recovery methods. This also applies to fields with a characteristic change in the operating mode at the later stages of field development.

Method of Maksimov M.I. (1959).

M.I. Maksimov, by studying the process of displacement of oil by water from a reservoir model, which is a pipe filled with sand, established an empirical dependence of the accumulated water production on the accumulated oil production.

Empirical coefficients.

Sazonov's method B.F. (1973).

The method proposed by B.F. Sazonov, is based on the assumption of a close connection between the accumulated production of oil and liquid, which is especially clearly manifested in the final stage of development of oil deposits.

where is the accumulated fluid production in reservoir conditions; - accumulated oil production in reservoir conditions; - empirical coefficients.

Well production is usually taken to be 0.02 - 0.05 (fraction of units) and 0.95-0.98 (fraction of units), respectively.

3rd group of field statistical methods for forecasting development indicators (displacement curves similar to the method of Pirverdyan A.M. (1970)).

This assumption forms the basis for a number of displacement characteristics, the main ones of which are presented in Table 2.3.

Pirverdyan's method A.M. (1970).

The dependence equation can be used in two modifications; this is the main expression proposed by A.M. Pirverdyan, and the expression converted to linear form. When moving to a linear form, it can be represented by the dependence

Method of Kambarov G.S. (1974).

This method, proposed by G.S. Kambarov and is a method similar to the method of Pirverdyan A.M. (1970), however, this method is based not on the inverse square relationship, but on a more simplified inverse relationship, between. The research conducted by the author of the method revealed the existence of a connection between the accumulated oil production and the accumulated production of liquid of the following type

where is the accumulated fluid production in reservoir conditions; - accumulated oil production in reservoir conditions; a, b - empirical coefficients. The dependence equation can also be used in two modifications; this is the main expression proposed by G.S. Kambarov (1974) (4.72), and the expression converted to linear form. When moving to a linear form, it can be represented by the dependence

Constant oil content method.

The constant oil content method represents a dependence of the form

This tendency is characteristic of objects at the final stage of development, when the water cut of the product reaches 95 - 98%, a further increase in water cut is associated with long-term operation, a sharp increase in the water-oil factor and, as a rule, the operation of the object is not economically justified. This method makes it possible to forecast oil production based on specified design values of liquid production at a late stage.

Method of Kazakov A.A. (1976).

A group of methods based on a power-law model of the dependence type Pirverdyan A.M. (1970) was generalized and improved by A.A. Kazakov in 1976. Kazakov A.A. generalized the presented type of models in relation to any type of phase permeability curves, provided that the Buckley-Leverett functional relationship is satisfied, in contrast, for example, to the model of A.M. Pirverdyan, which is applicable only for D.A. phase permeability curves. Efros.

4th group of field statistical methods for forecasting development indicators (displacement curves similar to the Govorova-Ryabinina method (1957)).

The Govorova-Ryabinina method (1957) is the determination of forecast development indicators when constructing displacement curves in logarithmic coordinates

It is assumed that this dependence, when plotted in given logarithmic coordinates, becomes linear when a certain stage of development is reached.

Method of Govorova G.L. - Ryabinina Z.K. (1957).

Dependence of accumulated water production on accumulated oil production

5th group of field statistical methods for forecasting development indicators (displacement curves similar to the method of Abyzbaev N.I. (1981)).

Method of Abyzbaev N.I. (1981) represents the determination of predictive development indicators when constructing displacement curves in logarithmic coordinates, i.e. the method is represented by a dependency of the form

This group of methods is based on a dependence of the form

The predicted cumulative water production that corresponds to the value or can be defined as

Keywords

INITIAL AND AVERAGE FORMATION PRESSURES / VOLUME OF ACCUMULATED AND INJECTED LIQUID / OIL VOLUMETRIC COEFFICIENTS/ GAS AND WATER / PHASE PERMEABILITIES / INITIAL AND AVERAGE RESERVOIR PRESSURES / VOLUMEES OF THE SAVED-UP AND PUMPED LIQUID/ VOLUME COEFFICIENTS OF OIL / GAS AND WATER / PHASE PERMEABILITY

annotation scientific article on energy and rational environmental management, author of the scientific work - Akramov Bakhshulla Shafievich, Naubeyev Temirbek Khasetullaevich, Sapashov Ikramzhan Yaumytbaevich, Sanetullaev Ernazar Esbosynovich, Eshmuratov Anvar Baltabaevich

The article discusses the issues of forecasting development indicators based on the characteristics of oil displacement by water using material balance methods. The material balance method allows you to solve a number of development problems, including forecasting technological indicators. To predict oil reservoir development indicators using the material balance method, the following data is required: initial and average reservoir pressures, volumes of accumulated and pumped liquid, volumes of water invading the formation, oil volumetric coefficients, gas and water, phase permeabilities, dynamic viscosities of oil and gas. The accuracy of indicators calculated using the material balance method depends on the selection of source data, their usefulness and on some of the assumptions made that form the basis of the calculation equations. It is also possible to predict the current oil saturation depending on the current oil recovery and the characteristics of oil, gas and water, and for the water pressure regime, the current average oil saturation for the reservoir is predicted by determining the volume of water invading the reservoir. Based on the equations of oil and gas flow in the reservoir, the relative permeability is determined. It can be considered that this method gives more plausible results, maintaining the existing development system without changing and naturally reducing the current liquid withdrawal at a later stage.

Forecasting of indicators of development according to characteristics of replacement of oil by water

In article questions of the forecast of indicators of development for characteristics of replacement of oil by water with use of methods of material balance are considered. The method of material balance allows to solve a number of problems of development including forecasting of technological indicators. The following data are necessary for forecasting of indicators of development of the oil pool by a method of material balance: initial and average reservoir pressures, volumes of the saved-up and pumped liquid, the water volumes interfering in layer, volume coefficients of oil, gas and water phase permeability, dynamic viscosity of oil and gas. Accuracy of the indicators counted by means of a method of material balance depends on selection of basic data, their full value and from the accepted some assumptions which are the basis for the settlement equations. It is also possible to predict the current oil saturation depending on the current characteristics of oil and oil, gas and water, and for water drive reservoir on the current average oil saturation is predicted by determining the amount of invading water reservoir. Based on the equations of flow of oil and gas reservoir, the relative permeability is determined. We can assume that this method gives more reliable results, keeping unchanged the existing system and the development of naturally reducing the current selection of the liquid at a late stage.

Text of scientific work on the topic “Forecasting development indicators based on the characteristics of oil displacement by water”

7universum.com

TECHNICAL SCIENCE

FORECASTING DEVELOPMENT INDICATORS BY CHARACTERISTICS OF OIL DISPLACEMENT BY WATER

Akramov Bakhshulla Shafievich

Ph.D. tech. Sciences, Associate Professor of the Department of Development and Operation of Oil and Gas gas fields, Associate Professor, Tashkent State Technical University, 100095, Republic of Uzbekistan, Tashkent, st. Universitetskaya, 2

E-mail: akramov bahsh@mail. ru

Naubeyev Temirbek Khasetullaevich

Ph.D. chem. sciences, head Department of Oil and Gas Technology, Associate Professor of Karakalpak state university names Berdakh, 230112, Republic of Karakalpakstan, Nukus, st. Ch. Abdirova 1

E-mail: timan05@mail. ru

Sapashov Ikramzhan Yaumytbaevich

Assistant at the Department of Oil and Gas Technology, Karakalpak State University named after Berdakh, 230112, Republic of Karakalpakstan, Nukus, st. Ch. Abdirova 1

E-mail: sapashov85@mail. ru

Sanetullaev Ernazar Esbosynovich

E-mail: ernazar. 91 @mail.ru

Eshmuratov Anvar Baltabaevich

Assistant, Department of Oil and Gas Technology, Karakalpak State University named after Berdakh, 230112, Republic of Karakalpakstan, Nukus, st. Ch. Abdirova 1

E-mail: anvar_12.8 7@mail. ru

Forecasting development indicators based on the characteristics of oil displacement by water // Universum: Technical Sciences: electron. scientific magazine Akramov B.Sh. [and etc.]. 2016. No. 7 (28). URL: http://7universum.com/ru/tech/archive/item/3413

FORECASTING OF INDICATORS OF DEVELOPMENT ACCORDING TO CHARACTERISTICS OF REPLACEMENT OF OIL BY WATER

Bahshullo Akramov

Candidate of Engineering sciences, Associate professor of Chair of development and operation oil and gas field,

Tashkent state technical university, 100095, Republic of Uzbekistan, Tashkent, Universitetskaja St., 2

Temirbek Naubeev

Candidate of Chemical Sciences, Head of Chair of technology of oil and gas, Associate professor of Karakalpak state university named after Berdakh, 230112, Republic of Karakalpakstan, Nukus, Ch. Abdirova St., 1

Ikramjan Sapashov

Assistant of Chair of technology of oil and gas, Karakalpak state university named after Berdakh, 230112, Republic of Karakalpakstan, Nukus, Ch. Abdirova St., 1

Ernazar Sanetullaev

Anvar Eshmuratov

Assistant of Chair of technology of oil and gas Karakalpak state university named after Berdakh, 230112, Republic of Karakalpakstan, Nukus, Ch. Abdirova St., 1

ANNOTATION

indicators calculated using the material balance method depend on the selection of initial data, their usefulness and on some of the assumptions made that form the basis of the calculation equations. It is also possible to predict the current oil saturation depending on the current oil recovery and the characteristics of oil, gas and water, and for the water pressure regime, the current average oil saturation for the reservoir is predicted by determining the volume of water invading the reservoir.

Based on the equations of oil and gas flow in the reservoir, the relative permeability is determined.

It is also possible to predict the current oil saturation depending on the current characteristics of oil and oil, gas and water, and for water drive reservoir on the current average oil saturation is predicted by determining the amount of invading water reservoir.

Based on the equations of flow of oil and gas reservoir, the relative permeability is determined.

We can assume that this method gives more reliable results, keeping unchanged the existing system and the development of naturally reducing the current selection of the liquid at a late stage.

Key words: initial and average reservoir pressure; volumes of accumulated and pumped liquid; volumetric coefficients of oil, gas and water; phase permeabilities;

Keywords: initial and average reservoir pressures; volumes of the saved-up and pumped liquid; volume coefficients of oil, gas and water; phase permeability;

The material balance method allows you to solve a number of development problems, including forecasting technological indicators.

To predict oil reservoir development indicators using the material balance method, the following data is required:

Initial and average reservoir pressures;

Volumes of accumulated and pumped liquid;

Volumes of water invading the formation;

Volumetric coefficients of oil, gas and water;

Phase permeabilities;

Dynamic viscosities of oil and gas.

This method makes it possible to predict current oil recovery from field data.

qo = k - bn0 + bg r - r) (1)

t q3 k + bg r - r) " (7

where: qu3 - accumulated volume of oil taken from the reservoir;

Q is the initial volume of oil in the reservoir;

K, bm0 - respectively, volumetric coefficients of oil at pressure p and

B - volumetric coefficient of gas at p;

Rr0, Rr, R - respectively, the volumes of dissolved gas per unit volume

oil at initial, current reservoir pressure and at the surface.

It is also possible to predict the current oil saturation depending on the current oil recovery and the characteristics of oil, gas and water, and for the water pressure regime, the current average oil saturation for the reservoir is predicted by determining the volume of water invading the reservoir.

Based on the equations of flow of oil and gas in the reservoir, the relative permeability is determined

K_(I - Yag)/ , (2)

kn bn Br Vn "

where: kn, kg - respectively, phase permeabilities for oil and gas;

i - total gas-oil factor;

/, / - respectively, the dynamic viscosity of oil and gas.

The accuracy of indicators calculated using the material balance method depends on the selection of source data, their usefulness and on some of the assumptions made that form the basis of the calculation equations.

If calculations using the material balance method use the characteristics of reservoir oils obtained during degassing in the RUT bomb, which are sharply different from the phenomena occurring in the reservoir, then predicting the average reservoir pressure leads to significant distortions of the results.

In a number of cases, forecasting oil field development indicators during waterflooding in fractured and fractured-porous reservoirs is carried out only on the basis of solving the material balance equation.

The dependence between the total oil production and the total liquid production is understood as the displacement characteristic, but subsequently the displacement characteristics began to be understood as the dependence of the total

oil production from total water production, as well as the dependence of various ratios between the total amounts of oil, water and liquid.

In addition, the displacement characteristics began to include the dependence between the content of oil or water in the flow and the total withdrawals of oil, water and liquid.

When predicting the development indicators of a long-term exploited field, when significant actual data on the extraction of oil and water are known, the calculation can be carried out using displacement characteristics.

To do this, first interpolate actual curves such as water cut - accumulated oil production, water cut - accumulated volume of injected water, current oil recovery - accumulated volume of injected water, and then extrapolate the resulting dependencies in order to obtain forecast indicators.

Most of the equations used to process displacement curves were obtained empirically as a result of the analysis of field data (methods of Kambarov, Nazarov, Kopytov, etc.). Some of the models were obtained as a result theoretical research the process of replacing oil with water in some simplified formulations.

The analysis shows that the characteristics of displacement can mainly be divided into two groups:

Integral characteristics of displacement;

Differential characteristics of displacement.

The first group includes all dependencies in the formulas of which the total withdrawals of oil, water and liquid appear.

The second contains all dependencies, the formulas of which include the oil or water content and the total withdrawals of oil, water and liquid.

As an alternative to traditional methods of displacement characteristics, one can consider the development equations used in the analytical methodology for calculating technological indicators

development of deposits under water pressure mode, used in TatNIPI oil.

This methodology assumes that the dynamics of current oil production and estimated liquid production under constant development conditions obey an exponential law. In this case, fluid extraction will decrease as watered wells are turned off, which is typical for the late stage of development. In addition, this methodology takes into account time-varying development conditions.

The TatNIPI oil method is based on the following two development dependencies:

chn _ Cho bn,

Chw acho acho

bn bop bog bn

where: Ch, Ch - respectively, the current flow rates of oil and water;

Cho - initial amplitude flow rate of all drilled and put into operation wells;

b, bzh - respectively, accumulated oil and liquid withdrawals; battles, &zhp - respectively, potential recoverable reserves of oil and liquid with an unlimited development period; a is the conversion factor.

In order to be able to use equations (3), it is necessary to approximate the observed actual dependencies of the specific values of current oil and water extractions by piecewise linear functions, reflecting the influence of the technological measures taken on the predicted final development indicators in dynamics.

Cho, bop, bop, and from the straight sections of the curves of the transformed actual dependencies, the filtration parameter /o is calculated.

Thus, using the proposed development equations, adapted to the operation history of the object, it is possible to predict the current and final development indicators.

It should be noted that the noted method needs further improvement, since the applied development equations do not cover the entire period of operation of the facility.

Bibliography:

1. Assessment of the efficiency of operational facilities at a late stage using displacement characteristics methods. / R.G. Khamzin, R.T. Fazlyev. -TatNIPI oil, Interval, No. 9 (44), 2002.

2. Reference manual for the design of development and operation of oil fields. Development design, oil production / Sh.K. Gimatutdinov, I.T. Mishchenko, A.I. Petrov and others - M.: Nedra, 1983, 463 pp., vol. I, 455 pp., vol. II.

1. Khamzin R.G., Fazlyev R.T. Evaluating the effectiveness of production facilities at a later stage by techniques of displacement characteristics. TatNIPIneft, Interval Publ., no. 9 (44), 2002. (In Russian).

2. Gimatutdinov Sh.K., Mishchenko I.T., Petrov A.I. Reference manual for the design, development and exploitation of oil fields. Design development, oil production. Moscow, Nedra Publ., 1983, 463 p., vol. I, 455 p., vol. II. (In Russian).

Oil displacement characteristics of the formula. Defense mechanisms of the psyche. Characteristics of basic defenses (Modern psychotechnologies of manipulation). Monitoring ongoing development

annotation scientific article on energy and rational environmental management, author of the scientific work - Akramov Bakhshulla Shafievich, Naubeyev Temirbek Khasetullaevich, Sapashov Ikramzhan Yaumytbaevich, Sanetullaev Ernazar Esbosynovich, Eshmuratov Anvar Baltabaevich

Related topics scientific works on energy and rational environmental management, author of the scientific work - Akramov Bakhshulla Shafievich, Naubeyev Temirbek Khasetullaevich, Sapashov Ikramzhan Yaumytbaevich, Sanetullaev Ernazar Esbosynovich, Eshmuratov Anvar Baltabaevich

Forecasting of indicators of development according to characteristics of replacement of oil by water

Text of scientific work on the topic “Forecasting development indicators based on the characteristics of oil displacement by water”

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Oil displacement characteristics of the formula. Defense mechanisms of the psyche. Characteristics of basic defenses (Modern psychotechnologies of manipulation). Monitoring ongoing development

annotation scientific article on energy and rational environmental management, author of the scientific work - Akramov Bakhshulla Shafievich, Naubeyev Temirbek Khasetullaevich, Sapashov Ikramzhan Yaumytbaevich, Sanetullaev Ernazar Esbosynovich, Eshmuratov Anvar Baltabaevich

Related topics scientific works on energy and rational environmental management, author of the scientific work - Akramov Bakhshulla Shafievich, Naubeyev Temirbek Khasetullaevich, Sapashov Ikramzhan Yaumytbaevich, Sanetullaev Ernazar Esbosynovich, Eshmuratov Anvar Baltabaevich

Forecasting of indicators of development according to characteristics of replacement of oil by water

Text of scientific work on the topic “Forecasting development indicators based on the characteristics of oil displacement by water”

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