CN115142826A - Method for predicting heat release of thick oil combustion - Google Patents
Method for predicting heat release of thick oil combustion Download PDFInfo
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- 238000004519 manufacturing process Methods 0.000 claims abstract description 30
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- 150000001335 aliphatic alkanes Chemical class 0.000 claims description 10
- 239000000446 fuel Substances 0.000 claims description 9
- BGHCVCJVXZWKCC-UHFFFAOYSA-N tetradecane Chemical compound CCCCCCCCCCCCCC BGHCVCJVXZWKCC-UHFFFAOYSA-N 0.000 claims description 8
- 230000015572 biosynthetic process Effects 0.000 claims description 7
- 230000008859 change Effects 0.000 claims description 7
- HOWGUJZVBDQJKV-UHFFFAOYSA-N docosane Chemical compound CCCCCCCCCCCCCCCCCCCCCC HOWGUJZVBDQJKV-UHFFFAOYSA-N 0.000 claims description 6
- DCAYPVUWAIABOU-UHFFFAOYSA-N hexadecane Chemical compound CCCCCCCCCCCCCCCC DCAYPVUWAIABOU-UHFFFAOYSA-N 0.000 claims description 6
- ZYURHZPYMFLWSH-UHFFFAOYSA-N octacosane Chemical compound CCCCCCCCCCCCCCCCCCCCCCCCCCCC ZYURHZPYMFLWSH-UHFFFAOYSA-N 0.000 claims description 6
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Abstract
The invention provides a method for predicting the heat release of thick oil combustion. The method comprises the following steps: step 1, burning target thickened oil through a burning pool device under the conditions of first pressure and first temperature rise rate, and obtaining CO and CO in combustion output gas by using a gas analyzer 2 The total production amount of (2); step 2, burning the normal paraffins with different carbon numbers by the combustion pool device under the conditions of second pressure and second heating rate to obtain CO and CO of the normal paraffins 2 A standard curve of total production; step 3, burning the target thickened oil obtained in the step 1 to produce CO and CO of gas 2 Interpolating the total generation amount of the target heavy oil into a standard curve to obtain the average carbon number of the combustion components of the target heavy oil; step 4, byAnd obtaining the heat release quantity of the combustion of the target thick oil by using a formula I, and further obtaining the static fire wire temperature value in the combustion process of the target thick oil by using a formula II and a formula III. The method is suitable for calculating the combustion amount in the thick oil fire flooding process and predicting the oil layer temperature field.
Description
Technical Field
The invention relates to the field of thickened oil fireflood technology exploitation, in particular to a method for predicting the combustion heat release of thickened oil.
Background
The fire flooding technology is always considered as a method for exploiting thick oil and ultra-thick oil with great potential, and the technology is applied to mines in a plurality of countries (such as the United states, romania and the like) through the development of nearly 100 years and is proved to be an efficient method for improving the recovery ratio of the thick oil. Compared with other methods for improving the recovery ratio, the in-situ combustion technology has the following advantages:
(1) Air is used as injection gas, so that the cost is low and the collection is easy;
(2) The components of the crude oil participating in underground combustion are mostly heavy components without industrial value, and the crude oil can be modified to a certain degree through fire flooding exploitation;
(3) Compared with other thermal oil extraction technologies, the heat loss and economic loss caused by medium heat dissipation can be avoided;
(4) The crude oil displacement efficiency is extremely high, almost no crude oil residue exists in a burnt area, and the oil reservoir recovery ratio is over 60 percent;
(5) The oil displacement mechanism comprises thermal viscosity reduction, steam flooding and CO 2 Non-miscible flooding and the like, and has good comprehensive oil displacement effect.
By quantitatively analyzing the underground combustion capacity and the heat contribution of the thickened oil, a calculation method of the temperature of the front edge of the live wire and the temperature field of the oil layer is established, so that a basis can be provided for predicting the fire flooding effect and optimizing and adjusting the fire flooding scheme.
The one-dimensional combustion pipe model is commonly used in the indoor experiment of the heavy oil fireflood, but due to the small volume, the heterogeneity of an oil layer and the problem of multiple production by one injection, the influence of important parameters such as the design of a gas injection scheme, the distribution of residual oil, the heterogeneity and the like on the fireflood effect is difficult to deeply research. Moreover, the spatial distribution rule of the front edge of the fire wire and the outer edge of the coking zone cannot be revealed, and the research on saturation field distribution, oil wall movement, output dynamics and the like cannot be carried out, so that the method is more limited. At present, in mine field tests at home and abroad, the problems of how to set a well pattern well spacing and how to adjust a gas injection scheme to obtain a more stable and effective fireflood process and the like are not researched deeply by a system. The influence of important parameters such as air injection rate, injection and production well pattern and well spacing on the fireflood effect is also urgently needed to be researched and proved. However, the most fundamental content in these studies is the study on the calculation method of the total heat release and the temperature of the front edge of the firing line in the underground combustion process of the heavy oil. Therefore, the importance and urgency of developing relevant studies is self evident.
In the indoor research, the temperature of the combustion front edge position of the thickened oil can be directly measured by experiments, and the heat release quantity can be converted into the environmental temperature by firstly obtaining the heat release quantity and then combining a chemical thermodynamic formula. In the process of on-site thick oil exploitation, the underground combustion process of thick oil must also consider the flow process, namely only part of heavy components of thick oil participate in the combustion reaction, and the rest part is heated and evaporated, is displaced by flue gas and flows into a production well after being mixed with cold oil. Therefore, by determining the average carbon number of the thickened oil combustion, the heat release of the thickened oil underground combustion process can be accurately obtained, and the temperature calculation result which is closer to the actual fireflood process can be further obtained.
Since thick oil is a complex mixture, which components burn off in an actual reservoir determines its exotherm and the temperature of the reservoir. Different oil layer conditions and gas injection processes cause great differences in burned components, so that the actual heat release is difficult to calculate accurately.
Disclosure of Invention
The invention mainly aims to provide a method for predicting the heat release of thick oil combustion, which aims to solve the problem that the actual heat release is difficult to accurately calculate due to complex components of thick oil in the prior art.
In order to achieve the above object, according to an aspect of the present invention, there is provided a method for predicting a thick oil combustion heat release, including the steps of: step 1, burning target thickened oil through a combustion pool device under a first pressure condition and a first temperature rise rate condition, and obtaining CO and CO in combustion output gas by using a gas analyzer 2 The total production amount of (c); step 2, under the conditions of second pressure and second heating rate, the normal alkanes with different carbon numbers are combusted through the combustion pool device to obtain CO and CO of the normal alkanes with different carbon numbers 2 A standard curve of the total production, wherein the second pressure condition is the same as the first pressure condition, the second temperature rise rate condition is the same as the first temperature rise rate condition, and the weight of the n-alkanes with different carbon numbers is respectively equal to the weight of the target thick oil; step 3, burning the target thickened oil obtained in the step 1 to produce CO and CO of gas 2 Interpolating the total generation amount into the standard curve obtained in the step 2 to obtain the average carbon number of the combustion components of the target thickened oil; step 4, obtaining the heat release of the combustion of the target thick oil through a formula I, and further obtaining the static fire wire temperature value of the combustion process of the target thick oil through a formula II and a formula III;
q =650n +200 formula I
Q crudeoil = c m Δ T equation II
T Live wire ＝T Virgin stratum + Δ T equation III
Wherein Q represents the heat release of combustion of the target thickened oil and has the unit of kJ; n is the average carbon number of the combustion components of the target heavy oil; q crudeoil Represents the total heat release of the combustion components of the thickened oil, and the unit is kJ; c represents the specific heat capacity of the reservoir rock and has the unit of J/(kg DEG C); m represents the volume of rock heated in m 3 (ii) a Delta T represents the maximum temperature difference of the reservoir environment before and after combustion, and the unit is; t is a unit of Live wire Representing a static firing line temperature value of the target heavy oil combustion process; t is Virgin earth formation Representing the reservoir initial temperature before fireflooding, from the production well test results of the target block;
further, step 1 comprises: quartz sand of 40-60 meshes is selected, the quartz sand and the target thick oil are stirred and mixed according to the mass ratio of 10.5, and a combustion pool device is sequentially filled according to the sequence of 5g of quartz sand at the bottom, 10.5g of mixed oil sand of the quartz sand and the target thick oil in the middle and 10g of quartz sand at the top; firstly, injecting nitrogen into the combustion pool device at the speed of 2L/min, and then injecting air into the combustion pool device at the speed of 2L/min; starting a heating furnace of the combustion pool device, linearly heating the heating furnace to 600 ℃ according to a first heating rate condition, wherein the injection rate of air is always unchanged; obtaining CO and CO in the generated gas in the combustion cell by a gas analyzer 2 To further obtain CO and CO in the gas generated by burning the target heavy oil 2 The total amount of production.
Further, in the step 2, the process conditions adopted in the process of combusting the n-alkanes with different carbon numbers by the combustion pool device are the same as those in the step S1.
Further, the n-alkanes of different carbon numbers are selected from n-dodecane, n-hexadecane, n-docosane, n-octacosane, n-tetradecane and n-forty-alkane.
Further, CO and CO 2 The step of generating the total production amount of (2) includes: measuring CO and CO in combustion gas of thickened oil or normal paraffin with different carbon numbers by using gas analyzer 2 The concentration change curve of (a); using the concentration variation curve to calculate CO and CO according to the following formula IV 2 Total production amount of (1):
wherein
Represents CO and CO 2 Q represents the injection rate of air in the combustion process,
represents CO and CO 2 Instantaneous concentration values.
Further, CO and CO in the combustion gas produced by burning the obtained heavy oil 2 Step 1 further comprises the step of calculating the fuel utilization according to equation v, following the total production:
FA represents fuel utilization and g is 2.
The invention is suitable for a method for calculating the combustion amount and predicting the oil layer temperature field in the process of thickened oil fire flooding, and utilizes a normal paraffin standard combustion curve (namely, CO released by combustion) obtained by a combustion pool experiment under the conditions of certain heating rate and certain pressure x The relation between the total amount and the carbon number), the average carbon number of the corresponding thickened oil combustion component can be obtained through interpolation, the total heat release in the thickened oil combustion process is further calculated, the calculated total heat value is converted into the highest temperature of environmental rise by using a specific heat capacity formula, and a basis is provided for researching the dynamic change of the front edge temperature and the coking zone and the temperature field distribution in the fire wire propelling process.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:
FIG. 1 is a schematic view showing the construction of a combustion cell apparatus employed in example 1 of the present invention;
FIG. 2 is a schematic view showing a charging method in a combustion bath according to example 1 of the present invention;
FIG. 3 shows CO + CO in the gas produced by burning heavy oil according to example 1 of the present invention 2 The concentration profile of (d);
FIG. 4 shows the carbon number and CO + CO in n-alkanes of different carbon numbers in example 1 according to the present invention 2 A standard curve corresponding to the total production;
FIG. 5 is a graph showing a high resolution technique for characterizing the number of carbons in heavy oil according to step 5 in example 1 of the present invention;
FIG. 6 is a schematic view showing a one-dimensional burner tube structure employed in step 6 in example 1 of the present invention;
FIG. 7 shows the results of the one-dimensional burner experiment according to step 6 in example 1 of the present invention.
Detailed Description
It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.
As described in the background section, since thick oil is a complex mixture, which components burn off in an actual reservoir determines its heat release and the temperature of the reservoir. Different oil layer conditions and gas injection processes cause great differences in burned components, so that the actual heat release is difficult to calculate accurately.
In order to solve the problem, the invention provides a method for predicting the heat release quantity of thick oil combustion, which comprises the following steps: step 1, burning target thickened oil through a combustion pool device under a first pressure condition and a first temperature rise rate condition, and obtaining CO and CO in combustion output gas by using a gas analyzer 2 The total production amount of (c); step 2, under the conditions of second pressure and second heating rate, the normal alkanes with different carbon numbers are combusted through the combustion pool device to obtain CO and CO of the normal alkanes with different carbon numbers 2 A standard curve of the total production, wherein the second pressure condition is the same as the first pressure condition, the second temperature-rising rate condition is the same as the second temperature-rising rate condition, and the weights of the normal paraffins with different carbon numbers are respectively equal to the weight of the target thickened oil; step 3, burning the target thickened oil obtained in the step 1 to produce CO and CO of gas 2 Interpolating the total generation amount of the heavy oil into the standard curve obtained in the step 2 to obtain the average carbon number of the combustion components of the target heavy oil; step 4, obtaining the heat release of the combustion of the target thick oil through a formula I, and further obtaining the static fire wire temperature value of the combustion process of the target thick oil through a formula II and a formula III;
q =650n +200 formula I
Q crudeoil = c · m · Δ t formula II
T Live wire ＝T Virgin earth formation + Δ T equation III
Wherein Q represents the heat release of combustion of the target thickened oil and has the unit of kJ; n is the average carbon number of the combustion components of the target heavy oil; q crudeoil Represents the total heat release of the combustion components of the thickened oil, and has the unit of kJ; c represents the specific heat capacity of the reservoir rock, and the unit is J/(kg DEG C); m represents the volume of rock heated in m 3 (ii) a Delta T represents the maximum temperature difference of reservoir environments before and after combustion, and the unit is; t is a unit of Live wire Representing the static fire line temperature value of the combustion process of the target heavy oil, and the unit is; t is Virgin earth formation Representing the reservoir initial temperature before fireflooding in degrees celsius, from the production well test results for the target block.
The invention is suitable for a method for calculating the combustion amount and predicting the oil layer temperature field in the process of thickened oil fire flooding, and utilizes a normal paraffin standard combustion curve (namely, CO released by combustion) obtained by a combustion pool experiment under the conditions of certain heating rate and certain pressure x The relation between the total amount and the carbon number), the average carbon number of the corresponding combustion components of the thickened oil can be obtained through interpolation, the total heat release of the thickened oil is further calculated, the calculated total heat value is converted into the highest temperature of environmental rise by using a specific heat capacity formula, and a basis is provided for researching the dynamic change of the front edge temperature and the coking zone and the temperature field distribution in the propelling process of the fire wire.
In order to better simulate the combustion environment of thick oil in the formation, in a preferred embodiment, step 1 comprises: quartz sand of 40-60 meshes is selected, the quartz sand and the target thick oil are stirred and mixed according to the mass ratio of 10.5; firstly, injecting nitrogen into the combustion pool device at the speed of 2L/min, and then injecting air into the combustion pool device at the speed of 2L/min; starting a heating furnace of the combustion pool device, linearly heating the heating furnace to 600 ℃ according to a first heating rate condition, wherein the injection rate of air is always unchanged; tong (Chinese character of 'tong')Obtaining CO and CO in the generated gas in the combustion pool through a gas analyzer 2 To further obtain CO and CO in the gas generated by burning the target heavy oil 2 The total amount of production. More preferably, the process conditions used in the combustion of the n-alkanes with different carbon numbers in step 2 by the combustion pool device are the same as those in step S1.
The invention adopts normal alkane with different carbon numbers as CO and CO 2 The test standard substance of the standard curve of the total generated quantity can avoid the influence of different molecular configurations and the like on the regularity of the heat release quantity as much as possible, so that the standard curve has stronger regularity, and the accuracy of the prediction method is further improved. In a preferred embodiment, the n-alkanes of different carbon numbers are selected from n-dodecane, n-hexadecane, n-docosane, n-octacosane, n-tetradecane and n-forty-alkane. The normal alkanes are selected, so that regularity is guaranteed, components with different carbon numbers in the thickened oil are reflected as much as possible, and the measured average carbon number of the thickened oil is more accurate.
Preferably, CO and CO 2 The step of generating the total production amount of (2) includes: measuring CO and CO in combustion gas of thickened oil or normal paraffin with different carbon numbers by using gas analyzer 2 The concentration change curve of (1); using the concentration variation curve to calculate CO and CO according to the following formula IV 2 Total production amount of (1):
wherein
Represents CO and CO 2 Q represents the injection rate of the gas in the combustion process,
represents CO and CO 2 Instantaneous concentration values.
In a preferred embodiment, CO and CO are present in the combustion gas resulting from the production of heavy oil 2 After the total amount of the product is produced,step 1 further comprises the step of calculating the fuel utilization according to formula v:
FA represents fuel utilization and g is 2.
Because of the conservation of carbon mole number in the combustion process, the fuel utilization rate FA of the crude oil can be obtained by the formula V, and the value of n is close to 2 according to the result of gas chromatographic analysis, so that the invention selects n to be equal to 2, namely the fuel utilization rate FA to be equal to 28 times of CO + CO 2 The total amount of production.
The present application is described in further detail below with reference to specific examples, which should not be construed as limiting the scope of the invention as claimed.
Example 1
The method comprises the following steps of burning heavy oil and normal paraffin with different carbon numbers by using a combustion pool device (figure 1, which comprises a combustion pool 1, a heating furnace 2, a temperature controller thermocouple 3, a temperature protection controller thermocouple 4, a gas flowmeter 5, a temperature protection controller 6, a room temperature measuring probe 7, a computer 8, a temperature controller 9, a filtering system 10, a gas analyzer 11 and a data recorder 12), obtaining the average carbon number of combustion components of the target heavy oil by interpolation on a standard curve according to the relationship that the gas generation amount is equal, further calculating the combustion amount by using an empirical formula, and predicting a temperature field, wherein the method specifically comprises the following steps:
step 1, in a combustion tank experiment (figure 2), quartz sand of 40-60 meshes is selected, the quartz sand and thick oil are fully stirred and mixed according to the mass ratio of 10.5, and the combustion tank is sequentially filled according to the sequence of '5 g of quartz sand A at the bottom, 10.5g of mixed oil sand B in the middle and 10g of quartz sand C at the top'. In the experimental stage, nitrogen gas was injected at a rate of 2L/min to remove miscellaneous gases, and then air was injected at a rate of 2L/min. After the oxygen content is stable, a certain heating rate is set, the heating furnace is started (the temperature is linearly raised from 25 ℃ to 600 ℃), and the air injection rate is kept unchanged at 2L/min all the time. CO + CO can be obtained by a gas analyzer 2 By the formula IV (FIG. 3)To obtain CO + CO 2 The total amount of production.
TABLE 1 State and purity of n-alkanes of different carbon numbers
| N-alkane species | State of matter | Purity of matter |
| N-dodecane | Liquid state | 98％ |
| N-hexadecane | Liquid state | 99％ |
| N-docosane | Solid powder | 98％ |
| N-octacosane | Solid powder | 99％ |
| N-tetradecane | Solid state crystallization | ＞95％ |
| N-forty alkane | Solid state crystallization | ＞97％ |
And 3, interpolating the result obtained in the step 1 to the standard curve obtained in the step 2 to obtain the average carbon number of the target thickened oil combustion component of 33-36.
And 4, obtaining the total heat release (14.8 KJ) and the fuel utilization rate FA (12-15%) of the target thick oil by using the formula I and the formula V, and further calculating the static fire wire leading edge temperature of the target thick oil by using the specific heat capacity formulas II and III (the method can still ensure that the relative error of the calculated temperature is within 10%).
And (3) verifying a prediction result:
for the verification of the average carbon number of the burning of the thickened oil, the method is provided for obtaining the carbon number distribution of the thickened oil by using a high-resolution technology, obtaining the total mass percentage of Cx (a certain carbon number) to Cmax (the detected maximum carbon number) by an abundance weighting method, and obtaining the average carbon number based on high-resolution mass spectrometry if the mass percentage is exactly equal to the percentage of the actually burnt component; and comparing the test results of the two, and carrying out rationality verification. In addition, the difference between the theoretical firing line front temperature and the actual combustion front temperature obtained through calculation can be verified through a one-dimensional combustion tube experiment, and then the error of the method is given. The method comprises the following specific steps:
and 5, characterizing the distribution of different carbon numbers in the thickened oil by utilizing a high-resolution technology (figure 5), and obtaining the average carbon number of the target thickened oil by an abundance weighting method. And comparing the average carbon number with the average carbon number obtained by the physical model experiment in the third step to obtain a corresponding error range.
The experimental phase of the burner tube includes a preheating phase and a combustion phase. In the preheating stage, nitrogen is injected at the speed of 2L/min, when the gas analyzer shows that the detected gas content is 0, an igniter is started (the ignition temperature is increased from 25 ℃ to 600 ℃ within 5 min), the igniter is kept working for 30 +/-10 min in the nitrogen atmosphere, and then the combustion stage is started. When the combustion stage starts, stopping introducing nitrogen, injecting air into the combustion tube at the speed of 3L/min, and keeping the working temperature of the igniter unchanged at 600 ℃ (preventing the fire flooding process from being unstable due to heat dissipation of the tube wall or heat carried by air and compensating the heat).
The experimental result of the one-dimensional combustion tube is shown in fig. 7, and under the condition that the temperature of the igniter T1 is kept unchanged, the T2 to T6 thermocouples measure the temperature at fixed points, so that the measured temperature is the temperature change of a certain position point in the whole fireflooding process, and the maximum temperature value of each temperature curve is regarded as the actually-measured temperature of the live wire in the research. Comparing with the static fire wire temperature obtained in step four, the relative error of the calculated temperature and the actual temperature can be obtained (table 2).
TABLE 2 relative error of actual versus predicted line temperature
| Calculated live line temperature value | Measured live line temperature value | Error temperature value | Relative error | |
| T 3 Temperature of | 382.4℃ | 374.9℃ | 7.5℃ | 2.00％ |
| T 4 Temperature of | 612.5℃ | 581.2℃ | 31.3℃ | 5.39％ |
| T 5 Temperature of | 496.3℃ | 485.9℃ | 10.4℃ | 2.14％ |
| T 6 Temperature of | 555.4℃ | 522.0℃ | 33.4℃ | 6.40％ |
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (6)
1. A method for predicting the heat release quantity of thick oil combustion is characterized by comprising the following steps:
step 1, burning target thickened oil through a combustion pool device under a first pressure condition and a first temperature rise rate condition, and obtaining CO and CO in combustion output gas by using a gas analyzer 2 The total production amount of (c);
step 2, under the conditions of second pressure and second heating rate, normal alkanes with different carbon numbers are combusted through the combustion pool device to obtain CO and CO of the normal alkanes with different carbon numbers 2 A standard curve of total production, wherein the second pressure condition is the same as the first pressure condition, the second temperature-rise rate condition is the same as the first temperature-rise rate condition, and the weight of the normal paraffin with different carbon numbers is respectively equal to the weight of the target heavy oil;
step 3, burning the target heavy oil obtained in the step 1 to produce CO and CO of gas 2 Interpolating the total generation amount of the target heavy oil into the standard curve obtained in the step 2 to obtain the average carbon number of the combustion components of the target heavy oil;
step 4, obtaining the heat release of the combustion of the target thick oil through a formula I, and further obtaining the static fire wire temperature value of the combustion process of the target thick oil through a formula II and a formula III;
q =650n +200 formula I
Q crudeoil = c m Δ T equation II
T Live wire ＝T Virgin stratum + Δ T equation III
Wherein Q represents the heat release of the combustion of the target thick oil and has the unit of kJ; n is the average carbon number of the target heavy oil combustion component; q crudeoil Represents the total heat release of the combustion components of the thickened oil, and has the unit of kJ; c represents the specific heat capacity of the reservoir rock and has the unit of J/(kg DEG C); m represents the volume of rock heated in m 3 (ii) a Delta T represents the maximum temperature difference of reservoir environments before and after combustion, and the unit is; t is Live wire A static firing line temperature value representative of the target heavy oil combustion process; t is Virgin earth formation Representing the reservoir initial temperature before fireflooding, from the production well test results for the target block.
2. The method for predicting thick oil combustion heat release according to claim 1, wherein the step 1 comprises:
selecting quartz sand with 40-60 meshes, stirring and mixing the quartz sand and the target thick oil according to a mass ratio of 10.5 to 0.5, and sequentially filling the combustion pool device with 5g of the quartz sand at the bottom, 10.5g of the mixed oil sand of the quartz sand and the target thick oil in the middle and 10g of the quartz sand at the top;
injecting nitrogen into the combustion pool device at a speed of 2L/min, and then injecting air into the combustion pool device at a speed of 2L/min;
starting a heating furnace of the combustion pool device, linearly heating the heating furnace to 600 ℃ according to the first heating rate condition, wherein the injection rate of the air is always unchanged during the period;
obtaining CO and CO in the generated gas in the combustion pool through a gas analyzer 2 To further obtain CO and CO in the gas produced by burning the target heavy oil 2 The total amount of production.
3. The method as set forth in claim 2, wherein the same process conditions as in the step 1 are adopted in the combustion of the n-paraffins having different carbon numbers in the step 2 using the combustion cell unit.
4. The method of predicting thick oil combustion exotherm according to any one of claims 1 to 3, wherein said n-alkanes of different carbon numbers are selected from n-dodecane, n-hexadecane, n-docosane, n-octacosane, n-tetradecane, and n-forty-ane.
5. Method for predicting the heat release of thick oil combustion according to any one of claims 1 to 3, characterized in that CO and CO 2 The step of generating the total production amount of (2) includes:
measuring the viscosity oil or the positive carbon number of different carbon numbers by a gas analyzerCO and CO in combustion product gas of alkane 2 The concentration change curve of (a);
using the concentration change curve to calculate CO and CO according to the following formula IV 2 Total production amount of (1):
wherein
Represents CO and CO 2 Q represents the injection rate of air in the combustion process,
represents CO and CO 2 Instantaneous concentration values.
6. The method of claim 5, wherein the method of predicting the calorific value of combustion of heavy oil comprises obtaining CO and CO in the gas produced by combustion of heavy oil 2 Said step 1 further comprises the step of calculating the fuel utilization according to the formula v, after the total production:
FA represents fuel utilization and g is 2.
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| US20050082057A1 (en) * | 2003-10-17 | 2005-04-21 | Newton Donald E. | Recovery of heavy oils through in-situ combustion process |
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| US20050082057A1 (en) * | 2003-10-17 | 2005-04-21 | Newton Donald E. | Recovery of heavy oils through in-situ combustion process |
| CN101818637A (en) * | 2010-04-26 | 2010-09-01 | 胡士清 | Method for improving recovery rate of thick massive viscous oil reservoir by controlling burning gas injection speed |
| CN103499511A (en) * | 2013-10-16 | 2014-01-08 | 南京林业大学 | Asphalt combustion process predicting method based on multistage thermal analysis kinetics models |
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