There are mainly two kinds of oil well measures, one is reservoir measures, and the other is wellbore measures. Reservoir measures mainly include fracturing, acidification, chemical water plugging, chemical sand control, sidetracking, workover and thermal recovery. Wellbore measures mainly include enlarging the pressure difference (such as deepening the pump hanger, lifting the pump (replacing the big pump), lowering the submersible pump, lowering the hydraulic piston pump, lowering the FRP rod, lowering the screw pump, gas lift, etc. ) and other wellbore measures (such as mechanical water plugging, mechanical sand control, overhaul (changing sets, shaping, salvaging falling objects, etc.). ), plugging, water injection well recovery, etc. ).
(B) Measures to increase production and the effectiveness of measures
Before the measures, the monthly normal production Qao and monthly decline rate of oil wells are Da, and after the measures, the monthly normal initial production of oil wells is Qbo and the monthly decline rate is Db. Assuming that the oil well reaches the monthly normal initial output Qbo within a short time after the measures, the variation law of oil well output before and after the measures is as follows (Figure 8-4-4).
Development of Deep High Pressure and Low Permeability Oilfield —— Taking Es3 Reservoir of Wendong Oilfield in Dongpu Depression as an Example
Where: Qat is the unmeasured production of the oil well in the t month; Qbt is the output of the oil well after the measurement in the t month.
The effective period of measures refers to the time when the oil well output drops to the output before measures, and the cumulative output during this period is measures to increase production.
There is at this time.
Development of Deep High Pressure and Low Permeability Oilfield —— Taking Es3 Reservoir of Wendong Oilfield in Dongpu Depression as an Example
It can be obtained from the above formula.
Development of Deep High Pressure and Low Permeability Oilfield —— Taking Es3 Reservoir of Wendong Oilfield in Dongpu Depression as an Example
Figure 8-4-4 Schematic Diagram of Production Change Measures
During the validity period, the cumulative output increment of measures is
Development of Deep High Pressure and Low Permeability Oilfield —— Taking Es3 Reservoir of Wendong Oilfield in Dongpu Depression as an Example
(3) Cost analysis of oilfield measures
According to the content of the project, the cost of measures is divided into two categories: direct cost and indirect cost. Direct cost refers to the cost that must be consumed when implementing a measure. The cost only depends on the content of the measures and changes with the change of the content of the measures. Indirect costs are shared costs (such as management fees, depreciation, etc. ) is not directly related to the measures. Direct costs can be divided into direct costs of one-time consumption and direct costs of installment withdrawal. Such as fracturing fluid, fracturing sand, acid fluid, annular protective fluid, etc. It belongs to the direct cost of one-time consumption, while electric pumps, tubing, high-strength sucker rods, cables, etc. It belongs to the direct cost of phased extraction.
(d) Incremental cost analysis of increasing oil production measures
The incremental cost of oil increasing measures refers to the increased cost due to incremental measures, which is expressed by the following formula:
Fixed incremental cost: SF = SM+δ SOF
Where: Sf is the fixed incremental cost; Sm is the cost of measurement.
Since the wages and benefits of production workers, maintenance operating expenses, repair expenses, well logging and well testing expenses, general oil well maintenance expenses and other production expenses will not change before and after the measures, the increased operating expenses Sof mainly include the increase of cost items such as material power, water injection and gas injection expenses, and oil and gas treatment expenses. Among them, the cost of materials and power is the direct increase cost of oil wells, depending on the type of measures.
1. Materials and power
Unless the oil production method is changed or the pump hanger is replaced, these two costs will generally not increase.
Increased material cost = effective period of measures ×30× (daily consumption of motor after measures-consumption before measures )× electricity price.
2. Water injection fee and oil and gas treatment fee
Increasing water injection and gas injection fee = sharing water injection and gas injection fee in block × measures to increase water injection quantity.
Increased oil and gas treatment fee = oil and gas treatment fee per ton of liquid in the block × measures to increase liquid volume.
(v) Restrictions on measures to increase oil supply.
After deduction, the measure oil increase limit can be expressed by the following formula:
Development of Deep High Pressure and Low Permeability Oilfield —— Taking Es3 Reservoir of Wendong Oilfield in Dongpu Depression as an Example
The initial marginal monthly production level after the measures can be obtained by substituting the above formula into the statistical formula for increasing production.
Development of Deep High Pressure and Low Permeability Oilfield —— Taking Es3 Reservoir of Wendong Oilfield in Dongpu Depression as an Example
This measure is beneficial when the oil increment is greater than the production limit of this measure or the daily output of the oil well after this measure is greater than. Using this method, the economic limit of increasing oil production by different measures in complex fault block oilfield is calculated, and the results are shown in Figure 8-4-5.
Figure 8-4-5 Limit Diagram of Measures to Increase Oil Quantity