Method and device for calculating solubility of elemental sulfur in sulfur-containing gas

Abstract

The invention belongs to the technical field of petroleum and natural gas exploration, and particularly relates to a method and device for calculating the solubility of elemental sulfur in sulfur-containing gas, the density of sulfur-containing natural gas, the mass change before and after the elemental sulfur is dissolved, the volume change after the elemental sulfur is dissolved and the like are obtained through a magnetic suspension balance, and the solubility of the elemental sulfur in the sulfur-containing gas is calculated through a simple formula. The solubility data of the elemental sulfur can be accurately and quickly obtained; meanwhile, the elemental sulfur loss caused by complex pipelines, intermediate containers and the like is reduced, the density precision of the sulfur-containing natural gas is improved, and the harm of corrosive sulfur-containing gas to an experimental system and the safety risk caused by gas leakage are reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of oil and natural gas exploration, and particularly relates to a method and a device for calculating the solubility of sulfur in sulfur-containing gas. Background Art

[0002] The special feature of high-sulfur gas reservoirs is that they contain elemental sulfur. Under high temperature and high pressure conditions in the reservoir, sulfur is mainly dissolved in acidic gases such as H2S and CO2. As the development of the gas reservoir proceeds, sulfur will precipitate with changes in pressure and temperature, blocking the reservoir storage space, wellbore space and ground gathering and transportation system, posing serious challenges to the efficient development of high-sulfur gas reservoirs. The solubility of sulfur in gas is one of the important parameters for evaluating changes in gas well production capacity and sulfur deposition and blockage in pipelines. Obtaining accurate sulfur solubility data is of great significance to the safe, clean and efficient development of high-sulfur gas reservoirs.

[0003] Patent document CN106124354A discloses an online sulfur solubility testing device and method for a high-sulfur gas reservoir. The testing device includes a dual-path sampling system, a CS2 elemental sulfur absorption system, a high-temperature and high-pressure reaction system for simulating a formation environment, a fluorescence sulfur determination system, a data acquisition system, and a cleaning and tail gas treatment system; the testing method includes sulfur-containing gas sample preparation, vacuum preparation, formation high-temperature and high-pressure environment simulation, elemental sulfur testing, total sulfur metering testing, total sulfur testing after sulfur dissolution reaction, data acquisition, cleaning tail gas treatment, etc.

[0004] Patent document CN109323953A discloses a method for determining the solubility of elemental sulfur in sulfur-containing gas, comprising: collecting sulfur-containing gas in a sulfur-containing gas reservoir, and determining a sampling temperature and a sampling pressure; transferring the sulfur-containing gas into a sample dispenser, and causing the sample dispenser to oscillate for a preset time at a preset temperature and a preset pressure; causing the pressure of the gas in the sample dispenser to drop to room pressure after passing through a back pressure valve, and then flowing into an adsorption tank; the gas flowing out of the adsorption tank passes through a gas flow meter, and the gas flow meter determines the volume of the sulfur-containing gas at room temperature and room pressure; collecting and transferring the carbon disulfide liquid in the adsorption tank to a collection tank; heating the collection tank and then cooling it, and determining the mass of the elemental sulfur in the collection tank; determining the room temperature and room pressure; and calculating the solubility of elemental sulfur in the sulfur-containing gas based on the sampling temperature, sampling pressure, room temperature, room pressure, the mass of elemental sulfur, and the volume of the sulfur-containing gas at room temperature and room pressure.

[0005] However, the prior art represented by the above patent documents still has the following problems: the existing experimental test methods mainly calculate the sulfur solubility parameter by obtaining the volume of the gas sample and the change in the weight of the liquid (such as CS2) before and after absorbing the sulfur. However, since the experimental device contains a large number of pipelines and valve systems, these test methods have experimental errors that are difficult to overcome, and the amount of sulfur remaining in the pipeline and valve system is large, resulting in large errors in the sulfur solubility experimental data.

[0006] At present, magnetic levitation balance has been used for the precise determination of fluid properties. The magnetic levitation balance fluid property test is accurate, safe and efficient. However, in the field of high sulfur content, especially in the determination and calculation of sulfur solubility, no corresponding method has been formed. Summary of the invention

[0007] Based on the above technical problems, the present invention proposes a method and a device for calculating the solubility of elemental sulfur in sulfur-containing gas, which can safely and efficiently obtain sulfur solubility change data under different temperature and pressure conditions.

[0008] The technical solution adopted by the present invention is as follows: a method for calculating the solubility of elemental sulfur in sulfur-containing gas, the method comprising the following steps:

[0009] Measuring the density ρ of sulfur sample 硫 ;

[0010] Prepare sulfur-containing gas with the same gas quality components as high-sulfur gas reservoirs;

[0011] The free volume V of the inner cavity when no object is suspended in the first closed shell of the sample chamber is obtained through the gas-containing intermediate container. 自由 ;

[0012] Use helium to perform a blank test and obtain the volume V of the sample basket when it is suspended in the first closed shell. 篮 ;

[0013] Place the sulfur sample in the sample basket and use nitrogen to perform a buoyancy test to obtain the initial volume V of the sulfur sample. 硫 ;

[0014] Discharging nitrogen in the first sealed shell of the magnetic levitation sulfur solubility measuring instrument, and performing vacuum treatment on the inner cavities of the first sealed shell and the second sealed shell;

[0015] Inject the sulfur-containing high-pressure gas into the first closed shell and the second closed shell respectively to perform a sulfur solubility test to obtain the volume of sulfur under different temperature and pressure conditions.

[0016] According to the density ρ of the sulfur sample 硫 , the free volume V of the inner cavity when no object is suspended in the first closed shell 自由 , the initial volume V of the sulfur sample 硫 And the volume of the sulfur element Calculate the solubility of elemental sulfur in sulfur-containing gases.

[0017] Furthermore, the free volume V of the inner cavity when no object is suspended in the first closed shell in the sample chamber is obtained by using the gas-containing intermediate container. 自由 Includes:

[0018] Inject nitrogen into the gas-containing intermediate container with a volume of V1, and the nitrogen pressure in the gas-containing intermediate container is P1; then connect the gas-containing intermediate container to the inner cavity of the first closed shell, and keep the temperature of the gas-containing intermediate container and the temperature of the inner cavity of the first closed shell both at T1; open the sample chamber air inlet valve, record the system pressure P2 after connection, obtain the nitrogen deviation factors Z1 and Z2 under the conditions of temperature T1, pressure P1 and pressure P2 respectively, and calculate V 自由 .

[0019] Furthermore, V 自由 The calculation formula is:

[0020]

[0021] Among them, V1 is the volume of the gas-containing intermediate container; P1 is the nitrogen pressure in the gas-containing intermediate container; P2 is the system pressure after the gas-containing intermediate container is connected with the inner cavity of the first closed shell; Z1 is the nitrogen deviation factor when the pressure is P1 and the temperature is T1; Z2 is the nitrogen deviation factor when the pressure is P2 and the temperature is T2.

[0022] Further, a blank test is performed using nitrogen to obtain the volume V of the sample basket when it is suspended in the first closed shell. 篮 :

[0023] The inner cavities of the first sealed shell and the second sealed shell are evacuated respectively; then high-pressure nitrogen is injected into the inner cavities of the first sealed shell and the second sealed shell at the same time, and after the pressure in the sealed shell is stabilized, the readings M of the first magnetic suspension balance at multiple different injection pressure points are measured and recorded 测 , the reading of the second magnetic suspension balance M 测2 and the helium density ρ 氦气 ;

[0024] According to the density of helium ρ 氦气 The reading M of the first magnetic suspension balance after helium injection 测 The linear relationship is fitted in the Cartesian coordinate system to solve the mass M of the sample basket. 篮 With volume V 篮 .

[0025] Furthermore, the mass of the sample basket M 篮 The calculation formula is:

[0026] M 篮 =M 测 +ρ 氮气 ×V 篮 ;

[0027] M 已知 =M 测2 +ρ 氮气 ×V 已知 ;

[0028] Among them, M 测 is the reading of the first magnetic suspension balance in the sample chamber at different pressure points; M 测2 is the reading of the second magnetic suspension balance in the fluid chamber at different pressure points; ρ 氦气 is the helium density calculated for the fluid chamber at different pressure points; M 篮 is the mass of the sample basket; V 篮 is the volume of the sample basket; M 已知 V is the mass of a standard object of known volume and weight suspended in a closed cavity in the fluid chamber; 已知 It is the volume of a standard object of known volume and weight suspended in a closed cavity in the fluid chamber.

[0029] Furthermore, the sulfur sample is placed in a sample basket, and a buoyancy test is performed using nitrogen to obtain an initial volume V of the sulfur sample. 硫 include:

[0030] Putting the sulfur sample into the sample basket, and performing vacuum treatment on the inner cavities of the first closed shell and the second closed shell respectively;

[0031] Then, nitrogen is injected into the first sealed shell and the second sealed shell at the same time. After the gases in the first sealed shell and the second sealed shell reach a balanced state, the readings M of the first magnetic suspension balance at different pressure points are obtained through buoyancy tests at different pressure points. 测 ', the reading of the second magnetic suspension balance M 测2 ';

[0032] According to the nitrogen density ρ 氮气 and the readings of the first magnetic suspension balance at different pressure points after nitrogen injection M 测 ', fit and solve the initial mass M of the sulfur sample in the Cartesian coordinate system 硫 and the initial volume V 硫 .

[0033] Furthermore, the initial volume V of the sulfur sample is 硫 The calculation formula is:

[0034] M 硫 +M 篮 =M 测 '+ρ 氮气 ×(V 篮 +V 硫 );

[0035] M已知 =M 测2 '+ρ 氮气 ×V 已知 ;

[0036] Among them, M 硫 is the initial mass of the sulfur sample; V 硫 is the initial volume of the sulfur sample.

[0037] Furthermore, the sulfur-containing gas is injected into the inner cavity of the first closed shell and the second closed shell respectively to perform a sulfur solubility test to obtain the volume of sulfur element under different temperature and pressure conditions. include:

[0038] The temperature of the inner cavity of the first closed shell and the second closed shell is set to the target gas reservoir temperature T 温度 ;

[0039] When the temperature of the target gas reservoir remains stable, the sample chamber air inlet valve and the fluid chamber air inlet valve are opened respectively, and the prepared sulfur-containing gas is injected into the inner cavity of the first closed shell and the second closed shell respectively, and the injection pressure is set to P1;

[0040] When the pressure in the first sealed shell and the second sealed shell is stable, the readings M of the first magnetic suspension balance are recorded respectively. 硫测 And the reading of the second magnetic suspension balance M' 硫测 ;

[0041] The density of sulfur-containing gas is obtained by the second magnetic suspension balance:

[0042]

[0043] Among them, M′ 硫测 is the temperature T i The readings of the second magnetic suspension balance under different pressures of sulfur-containing gas, When the temperature is the gas reservoir temperature, the pressure of the sulfur-containing gas in the second closed shell cavity is P i The density of sulfur gas sample at ;

[0044] According to the force analysis of the first magnetic suspension balance, there is the following relationship:

[0045]

[0046] Among them, M 硫测 is the temperature T i When the pressure of sulfur-containing gas in the first closed shell cavity is P i The reading of the first magnetic suspension balance at is the temperature T i When the pressure of sulfur-containing gas in the first closed shell cavity is P iWhen the sulfur crystals are saturated and dissolved in the sulfur-containing gas, the remaining sulfur sample volume; is the temperature T i When the pressure of sulfur-containing gas in the first closed shell cavity is P i When the sulfur crystals are saturated and dissolved in the sulfur-containing gas, the remaining sulfur sample mass;

[0047] because

[0048] The above formula can be transformed into:

[0049]

[0050] Then further:

[0051]

[0052] Further, the density ρ of the sulfur sample is 硫 , the free volume V of the inner cavity when no object is suspended in the first closed shell 自由 , the initial volume V of the sulfur sample 硫 and the remaining volume of the sulfur element after dissolving in the sulfur-containing gas Calculate the solubility of sulfur in sulfur-containing gases for:

[0053]

[0054] In addition, the present invention also proposes a device for realizing the above-mentioned method for calculating the solubility of sulfur in sulfur-containing gas, the device comprising: a magnetic suspension sulfur solubility measuring instrument and a sample chamber and a fluid chamber arranged inside the magnetic suspension sulfur solubility measuring instrument; wherein,

[0055] The sample chamber and the fluid chamber are connected via an air inlet line;

[0056] The inner cavity of the sample chamber is provided with a first magnetic suspension balance and a first closed housing, and the inner cavity of the first closed housing is provided with a sample chamber permanent magnet and a sample basket connected to each other, as well as a first pressure measurement system and a temperature control system;

[0057] The inner cavity of the fluid chamber is provided with a second magnetic suspension balance and a second closed shell, and the inner cavity of the second closed shell is provided with permanent magnets of the fluid chamber and standard objects of known volume and weight connected to each other, as well as a second pressure measurement system and a temperature control system.

[0058] Furthermore, the device also includes a sample chamber air inlet valve arranged outside the sample chamber, a fluid chamber air inlet valve arranged outside the fluid chamber, and an air inlet pipeline main valve, and the sample chamber air inlet valve, the fluid chamber air inlet valve and the air inlet pipeline main valve are all connected to the air inlet pipeline.

[0059] Furthermore, the first pressure measuring system and temperature control system are arranged at the bottom of the inner cavity of the first closed shell; the second pressure measuring system and temperature control system are arranged at the bottom of the inner cavity of the second closed shell; the first magnetic suspension balance is arranged above the first closed shell; and the second magnetic suspension balance is arranged above the second closed shell.

[0060] Compared with the sulfur solubility test method and test device in the prior art, the present invention uses a magnetic suspension balance to accurately obtain the density of sour natural gas, the mass change before and after the dissolution of sulfur, and the volume change after the dissolution of sulfur. Through simple formula calculation, the solubility data of sulfur can be accurately and quickly obtained; at the same time, the loss of sulfur caused by complex pipelines, intermediate containers, etc. is reduced, the accuracy of the density of sour natural gas is improved, and the harm to the experimental system due to corrosive sulfur-containing gas and the safety risks caused by gas leakage are reduced.

[0061] Other features and advantages of the present invention will be described in the following description, and part of them will become obvious from the description, or be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained through the description and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0063] Figure 1 The figure is a schematic diagram of a device for calculating the solubility of sulfur in sulfur-containing gas according to an embodiment of the present invention.

[0064] Figure numerals: 1. Magnetic levitation sulfur solubility meter; 2. Sample chamber; 3. First magnetic levitation balance; 4. First closed shell; 5. Permanent magnet in sample chamber; 6. Sample basket; 7. First pressure measurement system and temperature control system; 8. Air inlet valve in sample chamber; 9. Fluid chamber; 10. Second magnetic levitation balance; 11. Second closed shell; 12. Permanent magnet in fluid chamber; 13. Standard object of known volume and weight; 14. Second pressure measurement system and temperature control system; 15. Air inlet valve in fluid chamber; 16. Air inlet pipeline; 17 Air inlet pipeline main valve. DETAILED DESCRIPTION

[0065] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are 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.

[0066] like Figure 1 As shown, a device for realizing a method of calculating the solubility of sulfur in sulfur-containing gas according to the present invention is provided, which includes a magnetic suspension sulfur solubility measuring instrument 1 and a sample chamber 2 and a fluid chamber 9 arranged therein; wherein the sample chamber 2 and the fluid chamber 9 are connected via an air intake pipeline 16; one end of the air intake pipeline 16 is connected to an air intake pipeline main valve 17, and the other end of the air intake pipeline 16 is respectively connected to a sample chamber air intake valve 8 arranged outside the sample chamber 2 and a fluid chamber air intake valve 15 arranged outside the fluid chamber 9. A first magnetic suspension balance 3 and a first sealed housing 4 are arranged in the inner cavity of the sample chamber 2, and a sample chamber permanent magnet 5 and a sample basket 6 connected to each other, as well as a first pressure measurement system and a temperature control system 7 are arranged in the inner cavity of the first sealed housing 4; a second magnetic suspension balance 10 and a second sealed housing 11 are arranged in the inner cavity of the fluid chamber 9, and a fluid chamber permanent magnet 12, a standard object 13 with a known volume and weight, and a second pressure measurement system and a temperature control system 14 connected to each other are arranged in the inner cavity of the second sealed housing 11. The standard object 13 of known volume and weight is used to measure the density of sulfur-containing gas in the fluid chamber 9. The first pressure metering system and temperature control system 7 are arranged at the bottom of the inner cavity of the first closed shell 4; the second pressure metering system and temperature control system 14 are arranged at the bottom of the inner cavity of the second closed shell 11; the first magnetic suspension balance 3 is arranged above the first closed shell 4; the second magnetic suspension balance 10 is arranged above the second closed shell 11.

[0067] Through the above device, the specific steps of a method for calculating the solubility of sulfur in sulfur-containing gas provided in an embodiment of the present invention are as follows:

[0068] S1. During the maintenance of high-sulfur gas reservoirs, open the valve of the gathering and transportation network to obtain the deposited sulfur sample, crush it to 80-100 mesh, and dry the crushed sulfur sample at 100°C to reduce impurities such as moisture;

[0069] S2. Measure the density of the dry sulfur sample using a density meter 硫 ;

[0070] S3. According to the specific gas quality characteristics of the high-sulfur gas reservoir, pure component gas is used in the laboratory to artificially prepare sulfur-containing gas with the same gas quality components as the high-sulfur gas reservoir, wherein the artificially prepared sulfur-containing gas contains 10.5% H2S, 8.3% CO2 and 81.2% CH4;

[0071] S4, obtaining the free volume V of the inner cavity when no object is suspended in the first closed shell 4 in the sample chamber 2 of the magnetic levitation sulfur solubility measuring instrument 1 through the gas-containing intermediate container of known volume V1 自由 ;

[0072] S5. Perform a blank test using helium to obtain the volume V of the first closed shell 4 when the sample basket 6 is suspended. 篮 and quality M 篮 ;

[0073] S6. Place the sulfur sample in the sample basket 6 and perform a buoyancy test using nitrogen to obtain the initial mass m of the sulfur sample. 硫 and the initial volume V 硫 ;

[0074] S7, exhausting the nitrogen in the magnetic suspension sulfur solubility measuring instrument 1, and performing vacuum treatment on the inner cavities of the first closed shell 4 and the second closed shell 11;

[0075] S8. Inject artificially prepared sulfur-containing gas under high pressure to conduct sulfur solubility test and obtain the mass m of sulfur element samples under different pressure conditions at a gas reservoir temperature of 90°C. 硫 i and volume V 硫 i ;

[0076] S9, according to the density ρ of the sulfur sample 硫 , the free volume V of the inner cavity when no object is suspended in the first closed shell 4 自由 , the initial volume V of the sulfur sample 硫 And the volume of the sulfur element Calculate the solubility of elemental sulfur in sulfur-containing gases.

[0077] In the step S4, the free volume V of the inner cavity when no object is suspended in the first closed shell 4 in the sample chamber 2 of the magnetic levitation sulfur solubility measuring instrument 1 is obtained through the gas-containing intermediate container with a known volume V1. 自由 The steps are as follows:

[0078] A vacuum pump is used to evacuate the inner cavities of the first sealed shell 4 in the sample chamber 2 and the second sealed shell 11 in the fluid chamber 9 through the air inlet pipeline 16, and then nitrogen is injected into the gas-containing intermediate container through a gas booster pump. The volume of the gas-containing intermediate container is known to be V1, and the nitrogen pressure in the gas-containing intermediate container is P1. Then, the gas-containing intermediate container is connected to the first sealed shell 4 in the sample chamber 2 through a pipeline, and the temperature of the intermediate container is kept consistent with the temperature of the first sealed shell 4 in the sample chamber 2, that is, the gas reservoir temperature of 90°C; the fluid chamber air inlet valve 15 is opened, and the system pressure P2 after connection is recorded. The nitrogen deviation factors Z1 and Z2 under the conditions of gas reservoir temperature of 90°C, pressures P1 and P2 are obtained through the PR state equation. Then, according to Boyle's law, the free volume V of the inner cavity is calculated. 自由 for:

[0079]

[0080] Among them, V 自由 It is the free volume of the inner cavity when no object is suspended in the first closed shell 4; V1 is the volume of the gas-containing intermediate container; P1 is the nitrogen pressure in the intermediate container; P2 is the system pressure after the intermediate container is connected to the inner cavity of the first closed shell 4; Z1 is the nitrogen deviation factor at a pressure of P1 and a gas reservoir temperature of 90°C; Z2 is the nitrogen deviation factor at a pressure of P2 and a gas reservoir temperature of 90°C.

[0081] In step S5, a blank test is performed using helium to obtain the volume V of the first closed housing 4 when the sample basket 6 is suspended. 篮 and quality M 篮 The steps are as follows:

[0082] ① The first sealed shell 4 in the sample chamber 2 and the second sealed shell 11 in the fluid chamber 9 are evacuated by a vacuum pump through the air inlet line 16; then, under the condition of a gas reservoir temperature of 90°C, helium is simultaneously injected into the first sealed shell 4 in the sample chamber 2 and the second sealed shell 11 in the fluid chamber 9 through the air inlet line 16, and the pressure inside the two cavities is kept consistent, and the changes in the mass of the sample basket at multiple different injection pressure points are measured and recorded. 测 And the gas density data ρ 氮气 :

[0083] M 篮 =M 测 +ρ 氮气 ×V 篮 ;

[0084] M 已知 =M 测2 +ρ 氮气 ×V 已知 ;

[0085] Among them, M测 M is the data measured by the first magnetic suspension balance 3 at different pressure points; 测2 is the data measured by the second magnetic suspension balance 10 at different pressure points; ρ 氮气 is the helium density calculated through the fluid chamber 2 at different pressure points; M 篮 is the mass of the sample basket; V 篮 is the volume of the sample basket; M 已知 V is the mass of a standard object 13 of known volume and weight suspended in the closed cavity of the fluid chamber 9; 已知 is the volume of a standard object 13 of known volume and weight suspended in a closed cavity in the fluid chamber 9;

[0086] ② In the Cartesian coordinate system, according to the helium density ρ 氦气 The reading M of the first magnetic suspension balance 3 after the helium is injected 测 The linear relationship is fitted to solve the mass M of the sample basket 6 篮 With volume V 篮 .

[0087] In step S6, the sulfur sample is placed in the sample basket 6, and a buoyancy test is performed using nitrogen to obtain the initial mass m of the sulfur sample. 硫 and the initial volume V 硫 The steps are as follows;

[0088] ① Place the dried and ground sulfur sample into the sample basket 6, and evacuate the first sealed shell 4 in the sample chamber 2 and the second sealed shell 11 in the fluid chamber 9 through the air inlet line 16;

[0089] ② Then, at a gas reservoir temperature of 90°C, nitrogen is simultaneously injected into the first sealed shell 4 in the sample chamber 2 and the second sealed shell 11 in the fluid chamber 9 through the air inlet line 16, and the reading M of the first magnetic suspension balance 3 is obtained through buoyancy tests at different pressure points. 测 ', the reading M of the second magnetic suspension balance 10 测2 ' and nitrogen density ρ 氮气 , the measurement process satisfies the following relationship:

[0090] M 硫 +M 篮 =M 测 '+ρ 氮气 ×(V 篮 +V 硫 );

[0091] M 已知 =M 测2 '+ρ 氮气 ×V 已知 ;

[0092] Among them, M 硫 is the initial mass of the sulfur sample; V 硫 is the initial volume of the sulfur sample;

[0093] ③In the Cartesian coordinate system, the horizontal axis is the nitrogen density ρ 氮气 , the ordinate is the reading M of the first magnetic suspension balance 3 测 ', according to the nitrogen density ρ 氮气 and the readings M of the first magnetic suspension balance 3 at different pressure points after nitrogen injection 测 ', fitting to solve the initial mass M of the sulfur sample 硫 and the initial volume V 硫 .

[0094] In step S8, artificially prepared sulfur-containing gas is injected under high pressure to perform a sulfur solubility test to obtain the mass m of sulfur elemental samples under different pressure conditions at a gas reservoir temperature of 90°C. 硫 i and volume V 硫 i The steps are as follows:

[0095] ① Set the internal temperature of the first sealed shell 4 in the sample chamber 2 and the second sealed shell 11 in the fluid chamber 9 to the target gas reservoir temperature of 90°C;

[0096] ② When the temperature system remains stable, open the sample chamber air inlet valve 8 and the fluid chamber air inlet valve 15, and use the gas injection pump to inject the prepared sulfur-containing gas into the first closed shell 4 and the second closed shell 11 through the air inlet pipeline 16. The initial injection pressure is set to 5MPa. When the pressure system in the first closed shell 4 and the second closed shell 11 is stable, close the air inlet pipeline main valve 17, then close the sample chamber air inlet valve 8 and the fluid chamber air inlet valve 15, and record the readings M of the first magnetic suspension balance 3 respectively. 硫测 and the reading M of the second magnetic suspension balance 10 硫测 ';

[0097] The different pressures can only reach the target pressure by gradually increasing the pressure. In the embodiment of the present invention, the pressure is gradually increased by 5 MPa, and the measurement and recording are continued. The pressure test and recording are carried out in sequence until the target pressure reaches 50 MPa.

[0098] The density of sulfur-containing gas is obtained by the second magnetic suspension balance 10:

[0099]

[0100] Among them, M′ 硫测 is the reading of the second magnetic suspension balance 10 under sulfur-containing gas at a temperature of 90°C and a pressure of 5MPa, is the density of the sulfur-containing gas sample when the temperature is 90° C. and the sulfur-containing gas in the inner cavity of the second closed shell 11 is under the pressure condition of 5 MPa;

[0101] Without considering the adsorption of gas on the sulfur sample, the following relationship can be obtained based on the force analysis of the first magnetic suspension balance 3:

[0102]

[0103] Among them, M 硫测 is the reading of the first magnetic suspension balance 3 when the temperature is 90°C and the sulfur-containing gas in the inner cavity of the first closed shell 4 is under the pressure of 5MPa, When the temperature is 90°C and the pressure of the sulfur-containing gas in the inner cavity of the first closed shell 4 is 5 MPa, the remaining volume of the sulfur sample after the sulfur crystals are saturated and dissolved in the sulfur-containing gas; is the temperature T i When the pressure of sulfur-containing gas in the first closed shell 4 is P i When the sulfur crystals are saturated and dissolved in the sulfur-containing gas, the remaining sulfur sample mass;

[0104] because

[0105] The above formula can be transformed into:

[0106]

[0107] Then further:

[0108]

[0109] In the step S9, according to the density ρ of the sulfur sample 硫 , the free volume V of the inner cavity when no object is suspended 自由 , the initial volume V of the sulfur sample 硫 And the volume of the sulfur element The steps to calculate the solubility of elemental sulfur in sulfur-containing gases are as follows:

[0110] Further, by the above formula, combined with the free volume V of the inner cavity when no object is suspended in the first closed shell 4, 自由 , the initial volume V of the sulfur sample 硫 , the sulfur solubility parameter of sulfur-containing gas can be obtained when the temperature is 90°C and the pressure of sulfur-containing gas in the inner cavity is 5MPa due to the saturated dissolution of sulfur element powder crystals.

[0111]

[0112] In the above formula It is the solubility of the sulfur-containing gas when the temperature is 90°C and the pressure of the sulfur-containing gas in the sealed inner cavity 11 of the sample chamber is 5 MPa.

[0113] Subsequently, the pressure was gradually increased by 5 MPa, and the measurement and recording were continued. The pressure test and recording were repeated until the target pressure reached 50 MPa, and the sulfur solubility curves under different pressure conditions at a reservoir temperature of 90°C were plotted.

[0114] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein; and these modifications or substitutions do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for calculating the solubility of elemental sulfur in sulfur-containing gas, characterized in that: The method comprises the following steps: Measuring the density ρ of sulfur sample 硫 ; Prepare sulfur-containing gas with the same gas quality components as high-sulfur gas reservoirs; The free volume V of the inner cavity when no object is suspended in the first closed shell (4) in the sample chamber (2) is obtained through the gas-containing intermediate container. 自由 ; A blank test is performed using helium gas to obtain the volume V of the sample basket (6) when it is suspended in the first closed housing (4). 篮 ; The sulfur sample is placed in the sample basket (6), and a buoyancy test is performed using nitrogen to obtain the initial volume V of the sulfur sample. 硫 ; Discharging nitrogen from a first sealed shell (4) in a magnetically suspended sulfur solubility measuring instrument (1), and performing vacuum treatment on the inner cavities of the first sealed shell (4) and the second sealed shell (11); The sulfur-containing gas is injected into the inner cavity of the first closed shell (4) and the second closed shell (11) respectively to perform a sulfur solubility test to obtain the volume of sulfur element under different temperature and pressure conditions. According to the density ρ of the sulfur sample 硫 , the free volume of the inner cavity V 自由 , the initial volume V of the sulfur sample 硫 And the volume of the sulfur element Calculate the solubility of elemental sulfur in sulfur-containing gases.

2. The method according to claim 1, characterized in that The free volume V of the inner cavity when no object is suspended in the first closed shell (4) in the sample chamber (2) is obtained by using the gas-containing intermediate container. 自由 include: Nitrogen is injected into a gas-containing intermediate container of volume V1, and the nitrogen pressure in the gas-containing intermediate container is P1; then the gas-containing intermediate container is connected to the inner cavity of the first closed shell (4), and the temperature of the gas-containing intermediate container and the temperature of the inner cavity of the first closed shell (4) are maintained at T1; the sample chamber air inlet valve (8) is opened, and the system pressure P2 after the connection is recorded, and the nitrogen deviation factors Z1 and Z2 under the conditions of temperature T1, pressure P1 and pressure P2 are obtained respectively, and V 自由 .

3. The method according to claim 2, characterized in that V 自由 The calculation formula is: Wherein, V1 is the volume of the gas-containing intermediate container; P1 is the nitrogen pressure in the gas-containing intermediate container; P2 is the system pressure after the gas-containing intermediate container is connected to the inner cavity of the first closed shell (4); Z1 is the nitrogen deviation factor when the pressure is P1 and the temperature is T1; Z2 is the nitrogen deviation factor when the pressure is P2 and the temperature is T2.

4. The method according to claim 1, characterized in that: The blank test is performed using nitrogen to obtain the volume V of the sample basket (6) when it is suspended in the first closed shell (4). 篮 include: The inner cavities of the first sealed shell (4) and the second sealed shell (11) are respectively subjected to vacuum treatment; high-pressure nitrogen is then injected into the inner cavities of the first sealed shell (4) and the second sealed shell (11) at the same time, and after the pressure in the sealed shell is stabilized, the readings M of the first magnetic suspension balance (3) at multiple different injection pressure points are measured and recorded. 测 , the reading M of the second magnetic suspension balance (10) 测2 and the helium density ρ 氦气 ; According to the density of helium ρ 氦气 The reading M of the first magnetic suspension balance (3) after the helium is injected 测 The linear relationship is fitted in the Cartesian coordinate system to solve the mass M of the sample basket (6). 篮 With volume V 篮 .

5. The method according to claim 4, characterized in that The mass M of the sample basket (6) 篮 The calculation formula is: M 篮 =M 测 +r 氮气 ×V 篮 ; M 已知 =M 测2 +r 氮气 ×V 已知 ; Among them, M 测 is the reading of the first magnetic suspension balance (3) in the sample chamber (2) at different pressure points; M 测2 is the reading of the second magnetic suspension balance (10) in the fluid chamber (9) at different pressure points; ρ 氦气 M is the helium density calculated for the fluid chamber (9) at different pressure points; 篮 is the mass of the sample basket (6); V 篮 is the volume of the sample basket (6); M 已知 V is the mass of a standard object (13) of known volume and weight suspended in a closed cavity in the fluid chamber (9); 已知 It is the volume of a standard object (13) of known volume and weight suspended in a closed cavity in the fluid chamber (9).

6. The method according to claim 1, characterized in that The sulfur sample is placed in a sample basket (6), and a buoyancy test is performed using nitrogen to obtain an initial volume V of the sulfur sample. 硫 include: A sulfur sample is placed in a sample basket (6), and the inner cavities of the first sealed shell (4) and the second sealed shell (11) are respectively vacuumed; Then, nitrogen is injected into the first sealed shell (4) and the second sealed shell (11) at the same time. After the gases in the first sealed shell (4) and the second sealed shell (11) reach a state of equilibrium, the readings M of the first magnetic suspension balance (3) at different pressure points are obtained through buoyancy tests at different pressure points. 测 ', the reading M of the second magnetic suspension balance (10) 测2 '; According to the nitrogen density ρ 氮气 and the readings M of the first magnetic suspension balance (3) at different pressure points after nitrogen injection 测 ', fit and solve the initial mass M of the sulfur sample in the Cartesian coordinate system 硫 and the initial volume V 硫 .

7. The method according to claim 6, characterized in that The initial volume V of the sulfur sample 硫 The calculation formula is: M 硫 +M 篮 =M 测 '+ρ 氮气 ×(V 篮 +V 硫 ); M 已知 =M 测2 '+r 氮气 ×V 已知 ; Among them, M 硫 is the initial mass of the sulfur sample; V 硫 is the initial volume of the sulfur sample.

8. The method according to claim 1, characterized in that The sulfur-containing gas is injected into the inner cavities of the first closed shell (4) and the second closed shell (11) respectively to perform a sulfur solubility test to obtain the volume of sulfur element under different temperature and pressure conditions. include: The temperature of the inner cavity of the first closed shell (4) and the second closed shell (11) is set to the target gas reservoir temperature T 温度 ; When the temperature of the target gas reservoir remains stable, the sample chamber air inlet valve (8) and the fluid chamber air inlet valve (15) are opened respectively, and the prepared sulfur-containing gas is injected into the inner cavity of the first closed shell (4) and the second closed shell (11), and the injection pressure is set to P1; When the pressure in the inner cavity of the first sealed shell (4) and the second sealed shell (11) is stabilized, the readings M of the first magnetic suspension balance (3) are recorded respectively. 硫测 and the reading M′ of the second magnetic suspension balance (10) 硫测 ; The density of sulfur-containing gas is obtained by the second magnetic suspension balance (10): Among them, M′ 硫测 is the temperature T i The readings of the second magnetic suspension balance (10) under different pressures of sulfur-containing gas are: When the temperature is the gas reservoir temperature, the pressure of the sulfur-containing gas in the inner cavity of the second closed shell (11) is P i The density of sulfur gas sample at ; According to the force analysis of the first magnetic suspension balance (3), the following relationship can be obtained: Among them, M 硫测 is the temperature T i When the pressure of the sulfur-containing gas in the inner cavity of the first closed shell (4) is P i The reading of the first magnetic suspension balance (3) at , is the temperature T i When the pressure of the sulfur-containing gas in the inner cavity of the first closed shell (4) is P i When the sulfur crystals are saturated and dissolved in the sulfur-containing gas, the remaining sulfur sample volume; is the temperature T i When the pressure of the sulfur-containing gas in the inner cavity of the first closed shell (4) is P i When the sulfur crystals are saturated and dissolved in the sulfur-containing gas, the remaining sulfur sample mass; because The above formula can be transformed into: Then further:

9. The method according to claim 1, characterized in that: The density ρ of the sulfur sample 硫 , the free volume V of the inner cavity when no object is suspended in the first closed shell (4) 自由 , the initial volume V of the sulfur sample 硫 and the remaining volume of the sulfur element after dissolving in the sulfur-containing gas Calculate the solubility of sulfur in sulfur-containing gases for:

10. A device for implementing the method for calculating the solubility of elemental sulfur in sulfur-containing gas according to any one of claims 1 to 9, characterized in that: The device comprises: a magnetic suspension sulfur solubility measuring instrument (1) and a sample chamber (2) and a fluid chamber (9) arranged inside the magnetic suspension sulfur solubility measuring instrument; wherein: The sample chamber (2) and the fluid chamber (9) are connected via an air inlet line (16); The inner cavity of the sample chamber (2) is provided with a first magnetic suspension balance (3) and a first closed housing (4); the inner cavity of the first closed housing (4) is provided with a sample chamber permanent magnet (5) and a sample basket (6) connected to each other, as well as a first pressure measurement system and a temperature control system (7); The inner cavity of the fluid chamber (9) is provided with a second magnetic suspension balance (10) and a second closed shell (11); the inner cavity of the second closed shell (11) is provided with a permanent magnet (12) in the fluid chamber and a standard object (13) of known volume and weight connected to each other, as well as a second pressure measurement system and a temperature control system (14).

11. The device according to claim 10, characterized in that The device further comprises a sample chamber air intake valve (8) arranged outside the sample chamber (2), a fluid chamber air intake valve (15) arranged outside the fluid chamber (9), and an air intake pipeline main valve (17); the sample chamber air intake valve (8), the fluid chamber air intake valve (15), and the air intake pipeline main valve (17) are all connected to the air intake pipeline (16).

12. The device according to claim 10 or 11, characterized in that The first pressure metering system and temperature control system (7) are arranged at the bottom of the inner cavity of the first closed shell (4); the second pressure metering system and temperature control system (14) are arranged at the bottom of the inner cavity of the second closed shell (11); the first magnetic suspension balance (3) is arranged above the first closed shell (4); and the second magnetic suspension balance (10) is arranged above the second closed shell (11).

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