CN101231279A - Autoclave and high-pressure thermal simulation experiment method for high-pressure thermal simulation experiment - Google Patents

Abstract

The invention discloses a high-pressure autoclave used for a high-pressure thermal simulation experiment and a high-pressure thermal simulation experiment method, and belongs to the technical field of the petroleum geochemistry experiment. The high-pressure autoclave has the technical key point that the outer surface of the autoclave body is provided with a plurality of annular grooves, an tubular cavity of the autoclave body is provided with at least one ceramic stick, the outside diameter of which is little smaller than the inside diameter of the tubular cavity. The experiment method includes the steps that: (1) a standard sample is used for measuring the correcting temperature with different rates of temperature rise; (2) three golden tubes packaged with samples are arranged inside the autoclave body in sequence, then the ceramic stick is put in to ensure that the autoclave body is positioned inside a heating furnace chamber and a screw sealed part is positioned outside a heating furnace body, heating experiment begins under the setting rate of temperature rise according to a conventional method; (3) a gas yield curve is obtained and the temperature correction is performed; (4) data through the temperature correction is processed to obtain a nascent hydrocarbon dynamical parameter. The invention is used for the high-pressure thermal simulation experiment.

Description

Autoclave and high-pressure thermal simulation experiment method for high-pressure thermal simulation experiment

technical field

The invention relates to a device for petroleum geochemical experiments, more specifically, it relates to an autoclave used for high-pressure thermal simulation experiments, and also relates to a method for using the autoclave to perform high-pressure thermal simulation experiments.

Background technique

In petroleum geochemical experiments, it is necessary to encapsulate the rock sample in a gold tube, and then put the gold tube containing the sample into a high-pressure vessel (hereinafter referred to as an autoclave), and inject high-pressure water into the autoclave through a pipeline, and the high-pressure water A flexible gold tube is crushed to apply pressure to the sample. The autoclave with the gold tube is placed in an electric furnace for heating. Because the top of the autoclave is sealed with a thread with a cone at the bottom, when the pressure is not high, the whole part of the thread seal can be heated in an electric furnace, so that the entire autoclave can be heated evenly, so that the upper part of the autoclave The upper sample and the lower sample are subjected to the same temperature, which ensures the accuracy of the experiment. But in the case of high pressure (pressure greater than 100MP), if the threaded sealing part is heated in an electric furnace, when the temperature is greater than 500 °C, the threaded sealing part will creep, causing the autoclave to leak and the experiment to fail. Due to the above reasons, in the existing domestic and foreign high-temperature and high-pressure thermal simulation devices with a pressure greater than 50MP, in order to ensure the sealing, the top of the autoclave is placed outside the electric furnace, but the consequence of this is that the temperature of the top of the autoclave The temperature at the bottom is much lower than that at the bottom. According to actual measurements, when the temperature at the top of the autoclave is 500°C, the temperature at the bottom reaches 548°C. Moreover, this temperature difference is greatly affected by the environment and is not fixed, so it cannot be corrected. Due to the high pressure The temperature difference between the top and bottom of the kettle is very large. In order to avoid uneven heating, only a gold tube can be placed at the bottom during the experiment, which greatly prolongs the experiment time.

There are two reasons for the temperature gradient between the top and bottom of the autoclave, (1) the heat conduction of the autoclave metal body itself; (2) the convection of the fluid in the autoclave. In order to solve the problem of inconsistent temperature between the upper and lower parts of the autoclave, the designer of the present invention improved the existing autoclave and proposed an experimental scheme suitable for the operation of the autoclave, which can well solve the above problems.

Contents of the invention

The technical problem to be solved by the present invention is to provide an autoclave for high-pressure thermal simulation experiments that is simple in structure, easy to use, and capable of testing multiple samples at the same time.

Another technical problem to be solved by the present invention is to provide a high-pressure thermal simulation experiment method with high efficiency and accurate data.

The previous technical scheme of the present invention is achieved in this way: an autoclave for high-pressure thermal simulation experiments, including a kettle body, a sealing cone, a cone pressure cap, a liquid inlet pipe and a pipe pressure cap, and the inside of the kettle is There is a one-way open tubular cavity; the tapered part of the sealing cone is arranged on the opening side of the tubular cavity, and the sealing cone passes through the cone pressure cap arranged on the periphery of the sealing cone and the opening of the tubular cavity part crimping seal, the cone pressure cap is threadedly connected with the kettle body; the liquid inlet pipe passes through the sealing cone and communicates with the tubular cavity, and is fixed by the pipe pressure cap connected to the rear of the sealing cone. There is a drum-shaped sealing ring between the pressure cap and the pipe pressure cap, wherein the outer surface of the kettle body is provided with multiple annular grooves, and at least one section of ceramic rod is placed in the tubular cavity, and the outer diameter of the ceramic rod is slightly smaller than that of the tubular The inner diameter of the cavity.

In the above-mentioned autoclave used for high-pressure thermal simulation experiments, the annular groove communicates along the circumference of the kettle body; the outer diameter of the ceramic rod is 0.5mm smaller than the inner diameter of the tubular cavity.

The latter technical scheme of the present invention is achieved like this: a kind of high-pressure thermal simulation experiment method, comprises the following steps: (1) utilize standard sample to measure the correction temperature of different heating rates; (2) three gold tubes that are packaged with sample Put them into the tubular cavity of the kettle body described in this application in sequence, then put two ceramic rods, tighten the cone pressure cap and the tube pressure cap, and make the kettle body in the heating furnace cavity, and make the threaded sealing part in the heating furnace cavity. Outside the furnace, use a high-pressure pump to inject high-pressure water into the kettle body, and start the heating experiment according to the conventional method at the set heating rate; (3) analyze the gas yield curve and perform temperature correction; (4) correct the data after temperature correction After processing, the kinetic parameters of hydrocarbon generation are obtained.

In the above-mentioned a kind of high-pressure thermal simulation experiment method, the measuring method of step (1) is: (A) pressure is set to 50MP, standard sample is carried out temperature-raising experiment with conventional autoclave, and still body is all located in heating furnace chamber , draw the relational curve H of the methane production rate that experiment temperature and crude oil cracking generate; (B) pressure is set as 200MP, utilizes the autoclave described in claim 1 to carry out the experiment with the same heating rate, and makes still body be positioned at In the heating furnace chamber, the thread sealing part is located outside the heating furnace body, and the relationship curve I of the experimental temperature and the methane yield generated by cracking crude oil is obtained; (C) each temperature point corresponding to the curve I is gradually reduced by 1 ° C until the curve I H basically coincides with curve I, and the temperature that curve I decreases at this time is the corrected temperature.

Compared with the prior art, the present invention has the following advantages:

(1) Due to a series of annular grooves on the outside of the autoclave, the process of heat conduction from the lower part to the upper part is limited; the sealing effect of the thread can be guaranteed to prevent the failure of the experiment caused by leakage in high temperature and high pressure experiments.

(2) At the same time, because the ceramic rod is a poor conductor of heat, and because the gap between the outer diameter of the ceramic rod and the inner diameter of the tubular cavity is small, the passage of the high-pressure liquid in the tubular cavity of the autoclave to transfer heat to the upper part is blocked, so that The temperature difference between gold tube A and gold tube C is very small, thus ensuring that the three gold tubes A, B, and C containing the sample can be heated basically uniformly.

Description of drawings

The present invention will be described in further detail below in conjunction with the accompanying drawings and embodiments, but does not constitute any limitation to the present invention.

Fig. 1 is the structural representation of the specific embodiment of the present invention;

Fig. 2 is the use state figure of the present invention;

Fig. 3 is a schematic diagram of a traditional experimental state;

Fig. 4 is a schematic diagram of the experimental state of the present invention;

Fig. 5 is the relation graph of the methane productive rate that two kinds of experimental methods of standard sample among the present invention generate;

Fig. 6 is a corrected relational graph of the methane yield generated by two experimental methods of the standard sample in the present invention.

Detailed ways

Referring to shown in Fig. 1, the autoclave used for high-pressure thermal simulation experiment of the present invention comprises kettle body 1, sealing cone 2, cone pressure cap 3, liquid inlet pipe 4 and pipe pressure cap 5, in kettle body 1 There is a one-way open tubular cavity 11; the tapered part of the sealing cone 2 is arranged on the opening side of the tubular cavity 11, and the sealing cone 2 passes through the cone pressure cap 3 arranged on the periphery of the sealing cone 2 It is crimped and sealed with the opening of the tubular cavity 11, and the cone pressure cap 3 is threadedly connected with the kettle body 1; the liquid inlet pipe 4 passes through the sealing cone 2 and communicates with the tubular cavity 11, and is connected to the rear of the sealing cone 2 The pipe pressure cap 5 is fixed, and a drum-shaped sealing ring 6 is arranged between the sealing cone 2 and the pipe pressure cap 5. Tighten the pipe pressure cap 5, so that the drum-shaped sealing ring 6 can shrink inwardly under pressure and tighten Liquid inlet pipe (stainless steel pipe) 4, and guarantee the sealing between liquid inlet pipe 4 and sealing cone 2; To communicate with each other, the process of heat transfer from the lower part to the upper part is limited; two sections of ceramic rods 7 are placed in the tubular cavity 11, and the outer diameter of the ceramic rod 7 is 0.5 mm smaller than the inner diameter of the tubular cavity 11. 7 is a poor conductor of heat, and the gap between the outer diameter of the ceramic rod 7 and the tubular cavity 11 is small, which blocks the passage of the high-pressure water flowing to the upper part of the tubular cavity 11, so that the temperature difference in the tubular cavity 11 is very small, Therefore, it is ensured that a plurality of sample-containing gold tubes can be heated substantially uniformly and uniformly.

The high-pressure thermal simulation experiment method of the present invention is as follows:

(1) First determine the calibration temperature, the specific method is as follows:

(A) The pressure is set to 50MP, and a high-temperature and high-pressure pyrolysis experiment is carried out on a standard sample with a conventional autoclave. The schematic diagram of the experimental device is shown in Figure 3, and the still body 1' is all located in the furnace cavity of the heating furnace 10; The present invention adopts the crude oil in the Lungu area of Tarim Oilfield, Xinjiang as a standard sample, and carries out a temperature rise experiment of 2° C./hour. After the experiment, the relationship curve between the experimental temperature and the methane yield generated by the cracking of crude oil is obtained, as shown in the curve H in Fig. 5 (solid line).

(B) The pressure is set to 200MP, and the above-mentioned experiment is carried out using the autoclave of the present invention. Three gold tubes A, B, and C containing samples are placed in the tubular cavity 11 of the still body 1 in sequence, and then two gold tubes are placed on the top. Section ceramic rod 7, tighten the cone pressure cap 3 to make the sealing cone 2 seal the opening of the tubular cavity 11, then tighten the tube pressure cap 5, so that the drum-shaped sealing ring 6 shrinks inwardly due to compression deformation, and tightens Liquid inlet pipe 4, and guarantee the sealing between the liquid inlet pipe 4 and the sealing cone 2; The schematic view of experimental device is shown in Fig. 2 and Fig. 4, and still body 1 is positioned at the oven cavity of heating furnace 10, but thread seal Part is located outside the furnace body of the heating furnace 10; after the experiment ends, the relationship curve (golden tube A) of the methane yield generated by the experimental temperature and the cracking of crude oil is also obtained, as shown in the curve I (dotted line) in Fig. 5 .

(C) Gradually lower each temperature point corresponding to the curve I by 1°C, 2°C..., that is, gradually shift the curve I to the left end until the curve H basically coincides with the curve I, as shown in Figure 6; at this time, the curve I The shifted temperature is the correction temperature; the results show that for the temperature increase experiment of 2°C/hour, the correction temperature is 3°C.

Similarly, the above-mentioned calibrations were performed on gold tubes B and C in turn. The results show that for the temperature rise experiment of 2°C/hour, the temperature difference between gold tube A and gold tube C is less than 2°C, which can meet the experimental requirements of most samples. For samples that require high temperature accuracy, the temperature of gold tube A can be used as a reference, and the temperatures of gold tubes B and C are 1°C and 2°C lower than the temperature of gold tube A, respectively.

Use the same method to calibrate the temperature of experiments with different heating rates, and obtain the corrected temperature under the condition of a heating rate of 20°C. The results show that the corrected temperature is 5°C for the temperature rise experiment at 20°C/hour.

After measuring the corrected temperature of 20°C and a heating rate of 2°C/hour, the following experiment of thermal simulation can be carried out on the sample according to the conventional experiment procedure of autoclave.

(2) Three gold tubes A, B and C that are packaged with samples are put into the tubular cavity 11 of the kettle body 1 described in the application successively, then put into two ceramic rods 7, and tighten the cone pressure cap 3 and Pipe pressure cap 5, and make still body 1 be positioned at the furnace chamber of heating furnace 10, make thread sealing part be positioned at the furnace body of heating furnace 10, inject high-pressure water in kettle body 1 with high-pressure pump, respectively at 2 ℃/ hour and A heating rate of 20°C/hour was used to start the heating experiment.

(3) After heating, the gold tubes were taken out one by one, and the gas yield curve was analyzed and corrected for temperature.

(4) Process the temperature-corrected data to obtain hydrocarbon generation kinetic parameters.

Claims (6)

1. An autoclave for high-pressure thermal simulation experiments, comprising still body (1), sealing cone (2), cone pressure cap (3), liquid inlet pipe (4) and pipe pressure cap (5), The kettle body (1) is provided with a one-way open tubular cavity (11); the tapered part of the sealing cone (2) is arranged on the opening side of the tubular cavity (11), and the sealing cone (2) The cone pressure cap (3) arranged on the periphery of the sealing cone (2) is crimped and sealed with the opening of the tubular cavity (11), and the cone pressure cap (3) is threadedly connected to the kettle body (1) ; The liquid inlet pipe (4) passes through the sealing cone (2) and communicates with the tubular cavity (11), and is fixed by the pipe pressure cap (5) connected to the sealing cone (2) rear portion, and the sealing cone A drum-shaped sealing ring (6) is provided between the body (2) and the pipe pressure cap (5), and it is characterized in that, the outer surface of the kettle body (1) is provided with multiple annular grooves (12). At least one section of ceramic rod (7) is placed in the cavity (11), and the outer diameter of the ceramic rod (7) is slightly smaller than the inner diameter of the tubular cavity (11). 2. An autoclave for high-pressure thermal simulation experiments according to claim 1, characterized in that, said annular groove (12) communicates along the circumference of the kettle body (1). 3. An autoclave for high-pressure thermal simulation experiments according to claim 1, characterized in that the outer diameter of the ceramic rod (7) is 0.5 mm smaller than the inner diameter of the tubular cavity (11). 4. A high-pressure thermal simulation experiment method is characterized in that comprising the steps: (1) utilizing standard samples to measure the correction temperature of different heating rates; (2) packing three gold tubes (A, B, C) with samples Put them in the tubular cavity of the kettle body described in claim 1 in turn, then put two ceramic rods, tighten the cone pressure cap and the pipe pressure cap, and make the kettle body be located in the heating furnace cavity, so that the threaded sealing part is located Heating the outside of the furnace, injecting high-pressure water into the kettle body with a high-pressure pump, and starting the heating experiment according to the conventional method at a set temperature rise rate; (3) analyzing the gas yield curve and performing temperature correction; (4) correcting the temperature The data are processed to obtain the kinetic parameters of hydrocarbon generation. 5. method according to claim 4, it is characterized in that the assay method of step (1) is: (A) pressure is set to 50MP, standard sample is carried out temperature rise experiment with conventional autoclave, still body is all positioned at heating In the furnace cavity, draw the relational curve H of the methane production rate that experiment temperature and crude oil cracking generate; (2) pressure is set as 200MP, utilizes the autoclave described in claim 1 to carry out experiment with same heating rate, and makes The kettle body is located in the heating furnace cavity, so that the thread sealing part is located outside the heating furnace body, and the relationship curve I between the experimental temperature and the methane yield generated by cracking crude oil is obtained; (3) each temperature point corresponding to the curve I is gradually reduced by 1°C , until the curve H basically overlaps with the curve I, at this time the temperature of the curve I decreases is the correction temperature. 6. The method according to claim 4 or 5, characterized in that, the standard sample is crude oil in the Lungu area of Tarim Oilfield, Xinjiang.

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