Method for calculating economic limit water-oil ratio of land water-drive reservoir single well

Abstract

The invention provides a land water-drive reservoir single-well economic limit water-oil ratio calculation method, which utilizes single-well fixed cost, unit water injection fee, ton oil light hydrocarbon recharge fee, ton liquid oil and gas treatment fee, value-added tax rate, urban maintenance and construction tax rate, educational additional tax rate, resource tax rate, special earnings, exchange rate, injection-production ratio, production time rate and production well opening number. And according to an economic limit water-oil ratio calculation formula, the economic limit water-oil ratio of different oil prices and different single well average daily oil yields in the tth year is calculated. According to the method, the actual characteristic that the liquid production capacity continuously changes along with rising of the water-oil ratio is fully considered in the land water-drive reservoir single-well economic limit water-oil ratio calculation process, meanwhile, which physical quantity the variable cost item changes along is considered, and the calculated economic limit water-oil ratio better conforms to the actual development situation of the land water-drive reservoir.

Description

Technical Field

[0001] The invention belongs to the technical field of oilfield economic evaluation, and in particular relates to a method for calculating the economic limit water-oil ratio of a single well in an onshore water-drive oil reservoir. Background Art

[0002] The water-oil ratio is the ratio of water production to oil production, and is an important development indicator for water-driven oilfields. Currently, many onshore oilfields in my country have entered the high water content and ultra-high water content stages, and the water-oil ratio of some oil wells has even reached the economic limit, resulting in a continuous increase in development costs. Therefore, it is particularly important to reasonably determine the economic limit water-oil ratio. The economic limit water-oil ratio WOR is given in the "SY / T5367-2010 Method for Calculating Recoverable Petroleum Reserves", a petroleum and natural gas industry standard of the People's Republic of China issued by the National Energy Administration on August 27, 2010. EL The calculation formula is:

[0003]

[0004] Where: WOR EL is the economic limit water-oil ratio, in decimals (f); Q lm is the monthly liquid production, in tons (t); Q EL is the economic limit monthly oil production, in tons (t). The above formula can be used to obtain the economic limit water-oil ratio of a single well in a water-drive reservoir. However, this formula is calculated based on the premise of fixed liquid. In fact, whether for a single well or a block, the liquid production is a dynamic process that changes continuously with the development. In other words, as the water-oil ratio increases, the liquid production is constantly changing. Therefore, the calculation method of the economic limit water-oil ratio given in the national standard cannot accurately reflect the actual situation of onshore water-drive reservoir development. Summary of the invention

[0005] In order to overcome the deficiency that the existing economic limit water-oil ratio calculation method cannot accurately reflect the actual development situation of onshore water-drive oil reservoirs, the present invention provides a method for calculating the economic limit water-oil ratio of a single well in an onshore water-drive oil reservoir. The calculation result of this method is more in line with the actual development situation of onshore water-drive oil reservoirs.

[0006] The technical solution adopted by the present invention to solve the technical problem is:

[0007] A method for calculating the economic limit water-oil ratio of a single well in an onshore water-drive oil reservoir, comprising the following steps:

[0008] Step 1: Collect the evaluation parameters of the evaluation block, including: production operation fee, downhole operation fee, well logging and testing fee, maintenance and repair fee, transportation fee, factory and mine management fee, water injection fee, light hydrocarbon recovery fee, oil and gas processing fee, value-added tax rate, urban maintenance and construction tax rate, education surtax rate, resource tax rate, special revenue, exchange rate, injection-production ratio, production time rate, and number of production wells; wherein, the production operation fee, downhole operation fee, well logging and testing fee, maintenance and repair fee, transportation fee, and factory and mine management fee are fixed costs, which refer to various costs that are not affected by changes in production; the water injection fee, light hydrocarbon recovery fee, and oil and gas processing fee are variable costs; variable costs refer to various costs that change in direct proportion to the increase or decrease in product production, water injection fee is a cost related to the amount of water injection, light hydrocarbon recovery fee is a cost related to oil production, and oil and gas processing fee is a cost related to liquid production;

[0009] Step 2: Convert the fixed cost, water injection fee, light hydrocarbon recovery fee, and oil and gas processing fee of the evaluated block into the fixed cost of a single well, unit water injection fee, light hydrocarbon recovery fee per ton of oil, and oil and gas processing fee per ton of liquid;

[0010] Step 3: Utilize the above-mentioned fixed cost of single well, unit water injection fee, light hydrocarbon recovery fee per ton of oil, processing fee per ton of liquid oil and gas, value-added tax rate, urban maintenance and construction tax rate, education surtax rate, resource tax rate, special income fee, exchange rate, injection-production ratio, production hour rate, and number of production wells opened to calculate the economic limit water-oil ratio for different oil prices and different average daily oil production of single wells in year t according to the economic limit water-oil ratio calculation formula.

[0011] Compared with the existing calculation methods, the present invention takes into account more factors and parameters that affect the economic benefits, production costs, resource utilization and production plans of oil fields by adopting the above scheme, and can more accurately calculate the economic limit water-oil ratio, thereby better reflecting the actual situation.

[0012] Furthermore, the method further comprises the following steps:

[0013] Step 4: Establish a plane rectangular coordinate system about the average daily oil production of a single well and the economic limit water-oil ratio, wherein the average daily oil production of a single well is the abscissa and the economic limit water-oil ratio is the ordinate;

[0014] Step 5: Project the economic limit water-oil ratios of different crude oil prices and different average daily oil production of single wells in the tth year calculated in step 3 into the coordinate system established in step 4 to obtain the standard chart model of the economic limit water-oil ratio of single wells in the evaluation block.

[0015] Based on the established standard chart model of the economic limit water-oil ratio of a single well, the economic limit water-oil ratio of the oil field can be more intuitively reflected, so as to formulate a more reasonable production plan and improve the economic benefits and resource utilization of the oil field.

[0016] Furthermore, the economic limit water-oil ratio calculation formula in step 3 is as follows:

[0017]

[0018] Among them, WOR EL is the economic limit water-oil ratio, P O is the crude oil price, C fd is the annual fixed cost of a single well, R is the production rate, Q t is the average daily oil production of a single well in year t, C og is the light hydrocarbon recovery fee per ton of oil, C sg is the processing fee for ton of liquid oil and gas, C wg is the unit water injection fee, k is the injection-production ratio, β is the crude oil volume coefficient, r zz is the value added tax rate, r c is the urban maintenance and construction tax rate, r j is the education surtax rate, r zy is the resource tax rate, T tb For special income.

[0019] Furthermore, the economic limit water-oil ratio calculation formula is obtained by the following method: Calculate the fixed cost C per ton of oil per well fg , variable cost per ton of oil per well C Vg , and the tax on oil per ton per well T xo , the fixed cost per ton of oil per well C fg , variable cost per ton of oil per well C Vg , tax per ton of oil per well T xo Substitute into the break-even principle formula P 0 -C fg -C Vg -T xo =0 to obtain the calculation formula for the economic limit water-oil ratio.

[0020] Furthermore, the fixed cost per ton of oil per well C fg The calculation formula is as follows:

[0021]

[0022] Among them, C fd is the annual fixed cost of a single well, R is the production rate, Q t is the average daily oil production of a single well in year t.

[0023] Furthermore, the variable cost per ton of oil per well C Vg The calculation formula is as follows:

[0024] C Vg =C og +C sg ·(1+WORt )+C wg ·k·(β+WOR t )

[0025] Among them, C og is the light hydrocarbon recovery fee per ton of oil, C sg The processing fee for one ton of liquid oil and gas is WOR t is the water-oil ratio of the oil well in year t, C wg is the unit water injection fee, k is the injection-production ratio, and β is the crude oil volume coefficient.

[0026] Furthermore, the tax per ton of oil per well is T xo The calculation formula is as follows:

[0027] T xo =P o ·(r zz ·(r c +r j )+r zy )+T tb

[0028] Among them, P O is the crude oil price, r zz is the value added tax rate, r c is the urban maintenance and construction tax rate, r j is the education surtax rate, r zy is the resource tax rate, T tb For special income.

[0029] The beneficial effects of the present invention include:

[0030] The present invention uses various parameters such as single well fixed cost, unit water injection fee, light hydrocarbon recovery fee per ton of oil, oil and gas processing fee per ton of liquid, value-added tax rate, urban maintenance and construction tax rate, education surtax rate, resource tax rate, special income fee, exchange rate, injection-production ratio, production time rate, number of production wells opened, etc. to calculate the single well limit water-oil ratio of an onshore water-drive oil reservoir. The method fully considers the operating cost composition and related factors of the onshore water-drive oil reservoir development. In the calculation process, the actual characteristic that the liquid production volume changes continuously with the increase of the water-oil ratio is considered, so that the calculated single well economic limit water-oil ratio is more in line with the actual development situation of the onshore water-drive oil reservoir, so that the best exploitation plan of the onshore oil field can be determined more accurately, and the exploitation efficiency of the onshore oil field can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A graph is established for the economic limit water-oil ratio chart model for a specific single well. From bottom to top in the graph are the curves for oil prices of 30$ / bbl, 40$ / bbl, 50$ / bbl, 60$ / bbl, 70$ / bbl, 80$ / bbl, and 90$ / bbl. DETAILED DESCRIPTION

[0032] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0034] Example 1

[0035] The calculation method of the economic limit water content of a single well in an onshore water-driven oil reservoir includes:

[0036] Step 1, collecting evaluation parameters of the evaluation block, including production operation fee, downhole operation fee, well logging and testing fee, maintenance and repair fee, transportation fee, factory and mine management fee, water injection fee, light hydrocarbon recovery fee, oil and gas processing fee, value-added tax rate, urban maintenance and construction tax rate, education surtax rate, resource tax rate, special revenue, exchange rate, injection-production ratio, production time rate, and number of production wells; wherein the production operation fee, downhole operation fee, well logging and testing fee, maintenance and repair fee, transportation fee, and factory and mine management fee are fixed costs, which refer to various costs that are not affected by changes in production; the water injection fee, light hydrocarbon recovery fee, and oil and gas processing fee are variable costs, which refer to various costs that change in direct proportion to changes in product production, and the water injection fee is a cost related to the amount of water injection;

[0037] Among them: light hydrocarbon recovery fee is a fee related to oil production, oil and gas processing fee is a fee related to liquid production, and water injection fee is a fee related to water injection volume.

[0038] Step 2: convert the fixed cost, water injection fee, light hydrocarbon recovery fee, and oil and gas processing fee of the evaluated block into the fixed cost of a single well, unit water injection fee, light hydrocarbon recovery fee per ton of oil, and oil and gas processing fee per ton of liquid;

[0039] Step 3, using the above parameters, using formula (1) to calculate the economic limit water-oil ratio for different oil prices and different average daily oil production of single wells in year t,

[0040]

[0041] The specific method for obtaining formula (1) is given below:

[0042] The fixed cost per ton of oil per well is calculated using the following formula:

[0043]

[0044] Where: Cfg is the fixed cost per ton of oil per well, in Yuan / ton (Yuan / t); C fd is the annual fixed cost of a single well, in yuan / year (yuan / a); R is the production time rate, in decimals (f); Q t It is the average daily oil production of a single well in year t, in tons / day (tons / d).

[0045] The calculation formula for calculating the variable cost per ton of oil per well is as follows:

[0046] C Vg =C og +C sg ·(1+WOR t )+C wg ·k·(β+WOR t ) (3)

[0047] Where: C Vg is the variable cost per ton of oil per well, in Yuan / ton (Yuan / t); C og is the recovery fee of light hydrocarbons per ton of oil, in Yuan / ton (Yuan / t); C sg C is the processing fee per ton of liquid oil and gas, in Yuan / ton (Yuan / t); wg is the unit water injection fee, in yuan / ton (yuan / t); WOR t is the water-oil ratio of the oil well in year t, in decimals (f); k is the injection-production ratio, in decimals (f); β is the crude oil volume coefficient, in decimals (f).

[0048] The calculation formula for calculating the tax for a single well ton of oil is as follows:

[0049] T xo =P o ·(r zz ·(r c +r j )+r zy )+T tb (4)

[0050] Where: T xo P is the tax per ton of oil per well, in Yuan / ton (Yuan / t); o is the crude oil price, in Yuan / ton (Yuan / t); T tb is the special income, the unit is yuan / ton (yuan / t); r zz is the value added tax rate, in decimals (f); r c is the urban maintenance and construction tax rate, in decimal (f); r j is the education surtax rate, expressed as a decimal (f); r zy is the resource tax rate, in decimal (f).

[0051] According to the break-even principle:

[0052] P 0 -C fg -C Vg -T xo =0 (5)

[0053] Substituting equations (2), (3) and (4) into equation (5), we can obtain the economic limit water-oil ratio calculation formula as shown in equation (1).

[0054] Step 4, establishing a two-dimensional rectangular coordinate system, wherein the abscissa is the average daily oil production of a single well, and the ordinate is the economic limit water-oil ratio;

[0055] Step 5: Substitute the different crude oil prices P calculated in step 3 O The economic limit water-oil ratio of different single well average daily oil production in the tth year is projected into the established two-dimensional coordinate system, and the standard chart model of the economic limit water-oil ratio of a single well in the evaluation block can be obtained.

[0056] Example 2

[0057] The specific implementation process of determining the economic limit water-oil ratio chart model of a single well in the water-drive reservoir A in the Liaohe oil region according to Example 1 is as follows:

[0058] The first step is to collect evaluation parameters of water drive reservoir A, including production operation fee, downhole operation fee, well logging and testing fee, maintenance and repair fee, transportation fee, factory and mine management fee, water injection fee, light hydrocarbon recovery fee, oil and gas processing fee, value-added tax rate, urban maintenance and construction tax rate, education surtax rate, resource tax rate, special revenue, exchange rate, injection-production ratio, production time rate, and number of production wells. Among them, the production operation fee, downhole operation fee, well logging and testing fee, maintenance and repair fee, transportation fee, and factory and mine management fee are fixed costs, and the water injection fee, light hydrocarbon recovery fee, and oil and gas processing fee are variable costs; see Table 1;

[0059] Table 1 Parameters of water drive reservoir A in Liaohe oilfield

[0060] parameter unit Numeric Mining operation fee Yuan 15080674 Underground operation fee Yuan 1019038 Well logging and testing fees Yuan 613944 Maintenance and repair costs Yuan 2293267 Shipping Fees Yuan 476472 Factory and mine management fees Yuan 2771268 Water injection fee Yuan 705245 Light hydrocarbon recovery fee Yuan 575169 Oil and gas processing fee Yuan 2302712 VAT rate Decimal(f) 0.13 Urban maintenance and construction tax rate Decimal(f) 0.07 Education surtax rate Decimal(f) 0.05 Resource Tax Decimal(f) 0.0456 Special profit tax threshold USD / barrel 65 Ton barrel ratio of thin oil Decimal(f) 7.31 exchange rate Decimal(f) 6.3757 Injection-production ratio Decimal(f) 1 Production time rate Decimal(f) 0.82 Crude oil volume factor Decimal(f) 1.145 Number of production wells mouth 26 Annual liquid production 10,000 tons 163911 Annual oil production 10,000 tons 31922 Annual water injection 10,000 tons 303020

[0061] The second step is to convert the fixed cost, water injection fee, light hydrocarbon recovery fee, and oil and gas processing fee of water-driven reservoir A into single-well fixed cost, unit water injection fee, light hydrocarbon recovery fee per ton of oil, and oil and gas processing fee per ton of liquid, as shown in Table 2;

[0062] Table 2 Unit cost table of water drive reservoir A

[0063] parameter unit Numeric Fixed cost per well yuan / well 855949 Unit water injection fee <![CDATA[Yuan / ton 注水 > 2.3 Light hydrocarbon recovery fee per ton of oil <![CDATA[Yuan / ton 油 > 18.0 Ton of liquid oil and gas processing fee <![CDATA[Yuan / ton 液 > 14.0

[0064] The third step is to use the parameters in Table 1 and Table 2 and the formula (1) in Example 1 to calculate the economic limit water-oil ratio of the water-drive reservoir A at different oil prices and different average daily oil production of single wells in the tth year, as shown in Table 3;

[0065] Table 3 Economic limit water-oil ratio of a single well at different crude oil prices and different average daily oil production of a single well

[0066]

[0067] The fourth step is to establish a two-dimensional rectangular coordinate system, where the horizontal axis is the average daily oil production of a single well, and the vertical axis is the economic limit water-oil ratio;

[0068] The fifth step is to project the economic limit water-oil ratio of different crude oil prices and different average daily oil production of single wells in the tth year calculated in the third step into the established two-dimensional coordinate system to obtain the standard plate model of the economic limit water-oil ratio of a single well in water-driven reservoir A, see Figure 1 .

[0069] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A method for calculating the economic limit water-oil ratio of a single well in an onshore water-drive reservoir, wherein the characteristic steps are include: Step 1: Collect evaluation parameters of the evaluation block, including: production operation fee, downhole operation fee, well logging and testing fee, maintenance and repair fee, transportation fee, factory and mine management fee, water injection fee, light hydrocarbon recovery fee, oil and gas processing fee, value-added tax rate, urban maintenance and construction tax rate, education surtax rate, resource tax rate, special revenue, exchange rate, injection-production ratio, production time rate, and number of production wells; among which, the production operation fee, downhole operation fee, well logging and testing fee, maintenance and repair fee, transportation fee, and factory and mine management fee are fixed costs, and the water injection fee, light hydrocarbon recovery fee, and oil and gas processing fee are variable costs; Step 2: Convert the fixed cost, water injection fee, light hydrocarbon recovery fee, and oil and gas processing fee of the evaluated block into the fixed cost of a single well, unit water injection fee, light hydrocarbon recovery fee per ton of oil, and oil and gas processing fee per ton of liquid; Step 3: Utilize the above-mentioned fixed cost of single well, unit water injection fee, light hydrocarbon recovery fee per ton of oil, processing fee per ton of liquid oil and gas, value-added tax rate, urban maintenance and construction tax rate, education surtax rate, resource tax rate, special income fee, exchange rate, injection-production ratio, production hour rate, and number of production wells opened to calculate the economic limit water-oil ratio for different oil prices and different average daily oil production of single wells in year t according to the economic limit water-oil ratio calculation formula.

2. The method for calculating the economic limit water-oil ratio of a single well in an onshore water-drive reservoir according to claim 1, characterized in that: The following steps are also included: Step 4: Establish a coordinate system for the average daily oil production of a single well and the economic limit water-oil ratio; Step 5: Project the economic limit water-oil ratios of different crude oil prices and different average daily oil production of single wells in the tth year calculated in step 3 into the coordinate system established in step 4 to obtain the standard chart model of the economic limit water-oil ratio of single wells in the evaluation block.

3. The method for calculating the economic limit water-oil ratio of a single well in an onshore water-flooding reservoir according to claim 1, characterized in that: The economic limit water-oil ratio calculation formula in step 3 is as follows: Among them, WOR EL is the economic limit water-oil ratio, P O is the crude oil price, C fd is the annual fixed cost of a single well, R is the production rate, Q t is the average daily oil production of a single well in year t, C og is the light hydrocarbon recovery fee per ton of oil, C sg is the processing fee for ton of liquid oil and gas, C wg is the unit water injection fee, k is the injection-production ratio, β is the crude oil volume coefficient, r zz is the value added tax rate, r c is the urban maintenance and construction tax rate, r j is the education surtax rate, r zy is the resource tax rate, T tb For special income.

4. The method for calculating the economic limit water-oil ratio of a single well in an onshore water-drive reservoir according to claim 3, characterized in that: The economic limit water-oil ratio calculation formula is obtained by the following method: Calculate the fixed cost C per ton of oil per well fg , variable cost per ton of oil per well C Vg , and the tax on oil per ton per well T xo , the fixed cost per ton of oil per well C fg , variable cost per ton of oil per well C Vg , tax per ton of oil per well T xo Substitute into the break-even principle formula P0-C fg -C Vg -T xo =0 to obtain the calculation formula for the economic limit water-oil ratio.

5. The method for calculating the economic limit water-oil ratio of a single well in an onshore water-flooding reservoir according to claim 4, characterized in that: The fixed cost per ton of oil per well is C fg The calculation formula is as follows: Among them, C fd is the annual fixed cost of a single well, R is the production rate, Q t is the average daily oil production of a single well in year t.

6. The method for calculating the economic limit water-oil ratio of a single well in an onshore water-flooding reservoir according to claim 4, characterized in that: The variable cost per ton of oil per well is C Vg The calculation formula is as follows: C Vg =C og +C sg ·(1+WOR t )+C wg ·k·(β+WOR t ) Among them, C og is the light hydrocarbon recovery fee per ton of oil, C sg The processing fee for one ton of liquid oil and gas is WOR t is the water-oil ratio of the oil well in year t, C wg is the unit water injection fee, k is the injection-production ratio, and β is the crude oil volume coefficient.

7. The method for calculating the economic limit water-oil ratio of a single well in an onshore water-flooding reservoir according to claim 4, characterized in that: The tax for a single well ton of oil is T xo The calculation formula is as follows: T xo =P o ·(r zz ·(r c +r j )+r zy )+T tb Among them, P O is the crude oil price, r zz is the value added tax rate, r c is the urban maintenance and construction tax rate, r j is the education surtax rate, r zy is the resource tax rate, T tb For special income.

Images