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

Abstract

This invention belongs to the field of oil and gas exploration technology, and specifically relates to a method and apparatus for calculating the solubility of elemental sulfur in sulfur-containing gases. It utilizes a magnetic levitation balance to obtain the density of sulfur-containing natural gas, the mass change of elemental sulfur before and after dissolution, and the volume change of elemental sulfur after dissolution. Then, through a simple formula, it accurately and quickly obtains the solubility data of elemental sulfur. Simultaneously, it reduces the loss of elemental sulfur caused by complex pipelines and intermediate containers, improves the accuracy of sulfur-containing natural gas density, and reduces the harm to the experimental system caused by corrosive sulfur-containing gases and the safety risks caused by gas leaks.

Description

Technical Field

[0001] This invention belongs to the field of oil and gas exploration technology, and specifically relates to a method and apparatus for calculating the solubility of elemental sulfur in sulfur-containing gases. Background Technology

[0002] The unique characteristic of high-sulfur gas reservoirs lies in their presence of elemental sulfur. Under the high temperature and pressure conditions of the reservoir, elemental sulfur primarily dissolves in acidic gases such as H2S and CO2. As the reservoir develops, elemental sulfur precipitates out with changes in pressure and temperature, clogging the reservoir storage space, wellbore space, and surface gathering and transportation systems, posing a serious challenge to the efficient development of high-sulfur gas reservoirs. The solubility of elemental sulfur in gas is one of the important parameters for assessing changes in gas well productivity and the extent of sulfur deposition and blockage in pipelines. Obtaining accurate sulfur solubility data is of great significance for the safe, clean, and efficient development of high-sulfur gas reservoirs.

[0003] Patent document CN106124354A discloses an online testing device and method for sulfur solubility in high-sulfur gas reservoirs. The testing device includes a dual-channel sampling system, a CS2 absorption system for elemental sulfur, a high-temperature and high-pressure reaction system simulating the 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 measurement testing, total sulfur testing after sulfur dissolution reaction, data acquisition, and cleaning and tail gas treatment.

[0004] Patent document CN109323953A discloses a method for determining the solubility of elemental sulfur in sulfur-containing gas, comprising: collecting sulfur-containing gas from a sulfur-containing gas reservoir, and measuring the sampling temperature and sampling pressure; transferring the sulfur-containing gas into a sample mixing device, and oscillating the sample mixing device at a preset temperature and preset pressure for a preset time; allowing the gas in the sample mixing device to pass through a back pressure valve and then be reduced to the chamber pressure, and then flowing into an adsorption tank; passing the gas flowing out of the adsorption tank through a gas flow meter, and measuring the volume of the sulfur-containing gas at room temperature and chamber pressure; collecting the carbon disulfide liquid in the adsorption tank and transferring it to a collection tank; heating the collection tank and then cooling it, and measuring the mass of elemental sulfur in the collection tank; measuring the room temperature and chamber pressure; and calculating the solubility of elemental sulfur in the sulfur-containing gas based on the sampling temperature, sampling pressure, room temperature, chamber pressure, mass of elemental sulfur, and volume of sulfur-containing gas at room temperature and chamber pressure.

[0005] However, the existing technologies, represented by the aforementioned patent documents, still have the following problems: Existing experimental testing methods mainly calculate the solubility parameters of elemental sulfur by obtaining the changes in the volume of gas samples and the weight of liquids (such as CS2) before and after absorbing elemental sulfur. However, due to the presence of numerous pipelines and valve systems in the experimental apparatus, these testing methods suffer from insurmountable experimental errors. The large amount of elemental sulfur remaining in the pipelines and valve systems leads to significant errors in the sulfur solubility experimental data.

[0006] Currently, magnetic levitation balances have been applied to the precise determination of fluid properties. Magnetic levitation balances are characterized by precision, safety and efficiency in fluid property testing. However, in the field of high sulfur content, especially in the determination and calculation of sulfur solubility, no corresponding method has yet been formed. Summary of the Invention

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

[0008] The technical solution adopted in this invention is as follows: A method for calculating the solubility of elemental sulfur in sulfur-containing gases, the method comprising the following steps:

[0009] Measure the density ρ of a sulfur sample 硫 ;

[0010] Prepare sulfur-containing gases with the same gaseous composition as those in high-sulfur gas reservoirs;

[0011] The free volume V of the inner cavity of the first sealed shell in the sample chamber without any suspended objects was obtained by using a gas-containing intermediate container. 自由 ;

[0012] A blank test was performed using helium gas to obtain the volume V of the sample basket suspended in the first sealed shell. 篮 ;

[0013] The sulfur sample was placed in a sample basket, and a buoyancy test was performed using nitrogen gas to obtain the initial volume V of the sulfur sample. 硫 ;

[0014] Nitrogen gas was expelled from the first sealed shell of the magnetic levitation sulfur solubility measuring instrument, and the inner cavities of the first and second sealed shells were evacuated.

[0015] The sulfur-containing high-pressure gas was injected into the inner cavities of the first and second sealed shells, respectively, and sulfur solubility tests were conducted to obtain the volume of elemental sulfur under different temperature and pressure conditions.

[0016] Based on the density ρ of the sulfur sample 硫 The free volume V of the inner cavity when no object is suspended in the first sealed shell. 自由 The initial volume V of the sulfur elemental 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 of the first sealed shell within the sample chamber is obtained by using a gas-containing intermediate container when no object is suspended. 自由 Including:

[0018] Nitrogen gas is injected into a gas-containing intermediate container with a volume of V1, and the nitrogen pressure inside the intermediate container is P1. Then, the gas-containing intermediate container is connected to the inner cavity of the first sealed shell, maintaining the temperature of both the gas-containing intermediate container and the inner cavity of the first sealed shell at T1. The sample chamber inlet valve is opened, and the system pressure P2 after connection is recorded. The nitrogen deviation factors Z1 and Z2 under the conditions of temperature T1, pressure P1, and pressure P2 are obtained respectively, and V is calculated. 自由 .

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

[0020]

[0021] Wherein, V1 is the volume of the gas-containing intermediate container; P1 is the nitrogen pressure inside 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 sealed 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] Furthermore, a blank test was performed using nitrogen gas to obtain the volume V of the sample basket suspended in the first sealed shell. 篮 :

[0023] The inner cavities of the first and second sealed shells were evacuated. Then, high-pressure nitrogen gas was simultaneously injected into the inner cavities of both shells. After the pressure inside the sealed shells stabilized, the readings M of the first magnetic levitation balance at multiple different injection pressure points were measured and recorded. 测 The reading M of the second magnetic levitation balance 测2 and helium density ρ 氦气 ;

[0024] Based on the density ρ of helium 氦气 The reading M of the first magnetic levitation balance after helium injection 测 The linear relationship is used to fit the mass M of the sample basket in a Cartesian coordinate system. 篮 With volume V 篮 .

[0025] Furthermore, the mass M of the sample basket 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 The readings of the first magnetic levitation balance in the sample chamber at different pressure points; M 测2 The readings of the second magnetic levitation balance in the fluid chamber at different pressure points; ρ 氦气 The helium density calculated for the fluid chamber at different pressure points; M 篮 For the sample basket mass; V 篮 M is the volume of the sample basket; 已知 V is the mass of a standard object of known volume and weight suspended within a closed cavity in a fluid chamber; 已知 It is the volume of a standard object with known volume and weight suspended in a closed cavity within a fluid chamber.

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

[0030] The sulfur sample was placed in the sample basket, and the inner cavities of the first and second sealed shells were evacuated.

[0031] Nitrogen gas was then simultaneously injected into both the first and second sealed shells. After the gases in the first and second sealed shells reached equilibrium, the readings M of the first magnetic levitation balance at different pressure points were obtained through buoyancy tests. 测 '、The reading M of the second magnetic levitation balance 测2 ';

[0032] Based on the nitrogen density ρ 氮气 The readings M of the first magnetic levitation balance at different pressure points after nitrogen injection. 测 The initial mass M of the sulfur sample is obtained by fitting the coordinates in a Cartesian coordinate system. 硫 and initial volume V 硫 .

[0033] Furthermore, the initial volume V of the sulfur sample 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 V represents the initial mass of the sulfur sample. 硫 This represents the initial volume of the sulfur sample.

[0037] Furthermore, the sulfur-containing gas is injected into the inner cavities of the first and second sealed shells respectively to conduct sulfur solubility tests and obtain the volume of elemental sulfur under different temperature and pressure conditions. include:

[0038] The temperatures of the inner cavities of the first and second sealed shells are set as the target gas reservoir temperature T. 温度 ;

[0039] Once the target gas reservoir temperature has stabilized, the sample chamber inlet valve and the fluid chamber inlet valve are opened respectively, and the prepared sulfur-containing gas is injected into the inner cavities of the first and second sealed shells respectively, with the injection pressure set to P1.

[0040] After the pressure inside the first and second sealed shells stabilizes, the readings M of the first magnetic levitation balance are recorded respectively. 硫测 And the reading M′ of the second magnetic levitation balance 硫测 ;

[0041] The density of the sulfur-containing gas was obtained using a second magnetic levitation balance.

[0042]

[0043] Among them, M′ 硫测 For temperature T i The readings of the second magnetic levitation balance under different pressures of sulfur-containing gas. At the gas reservoir temperature, the pressure of the sulfur-containing gas inside the second sealed shell is P. i Density of sulfur-containing gas sample at that time;

[0044] Based on the force analysis of the first magnetic levitation balance, the following relationship exists:

[0045]

[0046] Among them, M 硫测 For temperature T i At that time, the pressure of the sulfur-containing gas inside the first sealed shell was P. i The first reading of the magnetic levitation balance at that time. For temperature T i At that time, the pressure of the sulfur-containing gas inside the first sealed shell was P. iAt that time, due to the saturation dissolution of sulfur elemental crystals in sulfur-containing gas, the remaining volume of the sulfur elemental sample; For temperature T i At that time, the pressure of the sulfur-containing gas inside the first sealed shell was P. i At that time, due to the saturation dissolution of sulfur elemental crystals in sulfur-containing gas, the remaining sulfur elemental sample mass;

[0047] because

[0048] The above equation can then be transformed into:

[0049]

[0050] Then we can further conclude:

[0051]

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

[0053]

[0054] Furthermore, this invention also proposes an apparatus for implementing the above-described method for calculating the solubility of elemental sulfur in sulfur-containing gases. The apparatus includes: a magnetically levitated sulfur solubility measuring instrument and a sample chamber and a fluid chamber disposed therein; wherein,

[0055] The sample chamber and the fluid chamber are connected by an air inlet pipeline;

[0056] The sample chamber is equipped with a first magnetic levitation balance and a first sealed shell. The first sealed shell is equipped with a permanent magnet for the sample chamber and a sample basket that are connected to each other, as well as a first pressure measurement system and a temperature control system.

[0057] The fluid chamber is equipped with a second magnetic levitation balance and a second sealed shell. The second sealed shell is equipped with a fluid chamber permanent magnet and a standard object of known volume and weight, as well as a second pressure measurement system and a temperature control system, which are interconnected.

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

[0059] Furthermore, the first pressure metering system and temperature control system are located at the bottom of the inner cavity of the first sealed housing; the second pressure metering system and temperature control system are located at the bottom of the inner cavity of the second sealed housing; the first magnetic levitation balance is located above the first sealed housing; and the second magnetic levitation balance is located above the second sealed housing.

[0060] Compared with existing methods and devices for testing sulfur solubility, this invention utilizes a magnetic levitation balance to accurately obtain the density of sulfur-containing natural gas, the mass change of elemental sulfur before and after dissolution, and the volume change of elemental sulfur after dissolution. Through simple formula calculations, the solubility data of elemental sulfur can be obtained accurately and quickly. At the same time, it reduces the loss of elemental sulfur caused by complex pipelines and intermediate containers, improves the accuracy of sulfur-containing natural gas density, and reduces the harm of corrosive sulfur-containing gases to the experimental system and the safety risks caused by gas leaks.

[0061] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention will be realized and obtained from the description and the drawings. Attached Figure Description

[0062] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

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

[0064] Reference numerals: 1. Magnetic levitation sulfur solubility measuring instrument; 2. Sample chamber; 3. First magnetic levitation balance; 4. First sealed shell; 5. Permanent magnet of sample chamber; 6. Sample basket; 7. First pressure measurement system and temperature control system; 8. Sample chamber inlet valve; 9. Fluid chamber; 10. Second magnetic levitation balance; 11. Second sealed shell; 12. Permanent magnet of fluid chamber; 13. Standard object with known volume and weight; 14. Second pressure measurement system and temperature control system; 15. Fluid chamber inlet valve; 16. Inlet pipeline; 17. Main valve of inlet pipeline. Detailed Implementation

[0065] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0066] like Figure 1 The diagram shows an apparatus for calculating the solubility of elemental sulfur in sulfur-containing gas, comprising a magnetically levitated sulfur solubility measuring instrument 1 and a sample chamber 2 and a fluid chamber 9 disposed within it. The sample chamber 2 and the fluid chamber 9 are connected by an inlet pipeline 16. One end of the inlet pipeline 16 is connected to a main inlet valve 17, and the other end is connected to a sample chamber inlet valve 8 disposed outside the sample chamber 2 and a fluid chamber inlet valve 15 disposed outside the fluid chamber 9. The sample chamber 2 contains a first magnetically levitated balance 3 and a first sealed housing 4. The first sealed housing 4 contains 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 fluid chamber 9 contains a second magnetically levitated balance 10 and a second sealed housing 11. The second sealed housing 11 contains a fluid chamber permanent magnet 12, a standard object 13 of known volume and weight, and a second pressure measurement system and a temperature control system 14 connected to each other. The standard object 13 with known volume and weight is used to measure the density of sulfur-containing gas in the fluid chamber 9. The first pressure measurement system and temperature control system 7 are located at the bottom of the inner cavity of the first sealed housing 4; the second pressure measurement system and temperature control system 14 are located at the bottom of the inner cavity of the second sealed housing 11; the first magnetic levitation balance 3 is located above the first sealed housing 4; and the second magnetic levitation balance 10 is located above the second sealed housing 11.

[0067] Using the above-described apparatus, the specific steps of a method for calculating the solubility of elemental sulfur in sulfur-containing gases provided in this embodiment of the invention are as follows:

[0068] S1. During the maintenance of high-sulfur gas reservoirs, open the valves of the gathering and transmission pipeline to obtain deposited elemental sulfur samples, crush them to 80-100 mesh, and dry the crushed elemental sulfur samples at 100℃ to reduce moisture and other impurities.

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

[0070] S3. Based on the specific gas composition characteristics of high-sulfur gas reservoirs, sulfur-containing gas with the same gas composition as high-sulfur gas reservoirs was artificially prepared in the laboratory using pure component gas. The artificially prepared sulfur-containing gas contained 10.5% H2S, 8.3% CO2, and 81.2% CH4.

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

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

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

[0074] S7. Expel the nitrogen gas from the magnetic levitation sulfur solubility measuring instrument 1 and perform vacuum treatment on the inner cavity of the first sealed shell 4 and the second sealed shell 11.

[0075] S8. High-pressure injection of artificially prepared sulfur-containing gas was conducted to perform sulfur solubility tests, and the mass m of elemental sulfur samples under different pressure conditions at a reservoir temperature of 90℃ was obtained. 硫 i and volume V 硫 i ;

[0076] S9. Based on the density ρ of the sulfur sample... 硫 The free volume V of the inner cavity of the first sealed shell 4 when no object is suspended. 自由 The initial volume V of the sulfur elemental sample 硫 and the volume of the sulfur element. Calculate the solubility of elemental sulfur in sulfur-containing gases.

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

[0078] Vacuum pumps are used to evacuate the inner cavities of the first sealed shell 4 in sample chamber 2 and the second sealed shell 11 in fluid chamber 9 via inlet pipe 16. Then, nitrogen is injected into the gas-containing intermediate container using a gas booster pump. The volume of the gas-containing intermediate container is known as V1, and the nitrogen pressure inside is P1. The gas-containing intermediate container is then connected to the first sealed shell 4 in sample chamber 2 via a pipeline, maintaining the temperature of the intermediate container at the same level as the temperature of the first sealed shell 4 in sample chamber 2, i.e., a gas reservoir temperature of 90℃. The inlet valve 15 of the fluid chamber is opened, and the system pressure P2 after connection is recorded. Using the PR equation of state, the nitrogen deviation factors Z1 and Z2 under the conditions of gas reservoir temperature 90℃ and pressures P1 and P2 are obtained. 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 V1 is the free volume of the inner cavity of the first sealed shell 4 when no object is suspended; P1 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 sealed shell 4; Z1 is the nitrogen deviation factor with pressure P1 and gas reservoir temperature of 90℃; Z2 is the nitrogen deviation factor with pressure P2 and gas reservoir temperature of 90℃.

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

[0082] ① Vacuum pumps were used to evacuate the inner cavities of the first sealed shell 4 in sample chamber 2 and the second sealed shell 11 in fluid chamber 9 via inlet line 16. Then, at a gas reservoir temperature of 90℃, helium gas was simultaneously injected into the inner cavities of the first sealed shell 4 in sample chamber 2 and the second sealed shell 11 in fluid chamber 9 via inlet line 16, maintaining consistent pressure within both cavities. The changes in sample basket mass M at multiple different injection pressure points were measured and recorded. 测 and 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 Data obtained from measurements taken by the first magnetic levitation balance 3 at different pressure points; M 测2 Data obtained from measurements taken by the second magnetic levitation balance 10 at different pressure points; ρ 氮气 The helium density calculated through fluid chamber 2 at different pressure points; M 篮 For the sample basket mass; V 篮 M is the volume of the sample basket; 已知 V is the mass of a standard object 13 of known volume and weight suspended within the sealed cavity of fluid chamber 9; 已知 The volume of a standard object 13 with known volume and weight suspended within the sealed cavity of fluid chamber 9;

[0086] ② In the Cartesian coordinate system, based on the helium density ρ 氦气 The reading M of the first magnetic levitation balance 3 after helium injection 测 The linear relationship is used to fit and solve for the mass M of sample basket 6. 篮 With volume V 篮 .

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

[0088] ① Place the dried and ground elemental sulfur sample into the sample basket 6, and evacuate the inner cavity 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 line 16.

[0089] ② Subsequently, at a gas reservoir temperature of 90℃, nitrogen gas was simultaneously injected into 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 gas inlet pipeline 16. The reading M of the first magnetic levitation balance 3 was obtained by buoyancy testing at different pressure points. 测 '、The reading M of the second magnetic levitation 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 V represents the initial mass of the sulfur sample. 硫 This represents the initial volume of the sulfur sample.

[0093] ③ In the Cartesian coordinate system, the horizontal axis represents the nitrogen density ρ. 氮气 The vertical axis represents the reading M of the first magnetic levitation balance 3. 测 ', based on the nitrogen density ρ 氮气 The readings M of the first magnetic levitation balance 3 at different pressure points after nitrogen injection. 测 ', Fit the solution to obtain the initial mass M of the sulfur sample 硫 and initial volume V 硫 .

[0094] In step S8, artificially prepared sulfur-containing gas is injected under high pressure to perform sulfur solubility testing, and the mass m of elemental sulfur samples under different pressure conditions at a gas reservoir temperature of 90℃ is obtained. 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℃;

[0096] ② Once the temperature system stabilizes, open the sample chamber inlet valve 8 and the fluid chamber inlet valve 15. Using the gas injection pump, inject the prepared sulfur-containing gas into the inner cavities of the first sealed shell 4 and the second sealed shell 11 through the inlet pipeline 16. The initial injection pressure is set to 5 MPa. After the pressure system inside the first sealed shell 4 and the second sealed shell 11 stabilizes, close the main inlet pipeline valve 17, and then close the sample chamber inlet valve 8 and the fluid chamber inlet valve 15. Record the readings M of the first magnetic levitation balance 3. 硫测 And the reading M of the second magnetic levitation balance 10 硫测 ';

[0097] The different pressures can only be achieved by gradually increasing the pressure. In this embodiment of the invention, the pressure is gradually increased by 5 MPa, and measurements and records are continued. This process of increasing pressure and recording is repeated until the target pressure of 50 MPa is reached.

[0098] The density of the sulfur-containing gas was obtained using the second magnetic levitation balance 10.

[0099]

[0100] Among them, M′ 硫测 This is the reading of the second magnetic levitation balance 10 at 90℃ under sulfur-containing gas at 5MPa pressure. The density of the sulfur-containing gas sample is given at a temperature of 90℃ and a pressure of 5MPa in the inner cavity of the second sealed shell 11.

[0101] Neglecting the adsorption of gas on the sulfur sample, the following relationship exists based on the force analysis of the first magnetic levitation balance 3:

[0102]

[0103] Among them, M 硫测 The reading is that of the first magnetic levitation balance 3 at a temperature of 90℃ and with sulfur-containing gas in the inner cavity of the first sealed shell 4 under a pressure of 5MPa. When the temperature is 90℃ and the pressure of the sulfur-containing gas in the inner cavity of the first sealed shell 4 is 5 MPa, the remaining volume of the sulfur elemental sample after the sulfur elemental crystals are saturated and dissolved in the sulfur-containing gas. For temperature T i At that time, the pressure of the sulfur-containing gas inside the first sealed shell 4 was P. i At that time, due to the saturation dissolution of sulfur elemental crystals in sulfur-containing gas, the remaining sulfur elemental sample mass;

[0104] because

[0105] The above equation can then be transformed into:

[0106]

[0107] Then we can further conclude:

[0108]

[0109] In step S9, based on 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 elemental sample 硫 and the volume of the sulfur element. The steps for calculating the solubility of elemental sulfur in sulfur-containing gases are as follows:

[0110] Furthermore, by applying the above formula, and combining it with the free volume V of the inner cavity of the first sealed shell 4 when no object is suspended, 自由 The initial volume V of the sulfur sample 硫 The sulfur solubility parameter of the sulfur-containing gas can be obtained when the temperature is 90℃ and the pressure of the sulfur-containing gas in the inner cavity is 5MPa, after the sulfur elemental powder crystals have been saturated and dissolved.

[0111]

[0112] In the above formula The solubility of sulfur-containing gas is given at a temperature of 90℃ and a pressure of 5MPa in the sealed inner cavity 11 of the sample chamber.

[0113] Subsequently, the pressure was gradually increased by 5 MPa, and measurements and records were continued. This process of increasing pressure and recording was repeated until the target pressure of 50 MPa was reached, and 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 foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method of calculating the solubility of elemental sulfur in a sulfur-containing gas, characterized by, The method is based on device implementation, the device comprises: a magnetic levitation sulfur solubility measuring instrument (1) and a sample chamber (2) and a fluid chamber (9) arranged inside; wherein, The sample chamber (2) and the fluid chamber (9) are connected through a gas inlet pipeline (16); The sample chamber (2) is provided with a first magnetic levitation balance (3) and a first sealed shell (4) in the cavity, the first sealed shell (4) is provided with a sample chamber permanent magnet (5) and a sample basket (6) connected with each other, and a first pressure measurement system and a temperature control system (7) in the cavity; The fluid chamber (9) is provided with a second magnetic levitation balance (10) and a second sealed shell (11) in the cavity, The second sealed shell (11) is provided with a fluid chamber permanent magnet (12) and a standard object (13) with a known volume and weight connected with each other, and a second pressure measurement system and a temperature control system (14) in the cavity; The method comprises the following steps: Measuring the density of elemental sulfur samples ; Prepare a sulfur-containing gas with the same gas quality components as the high-sulfur gas reservoir; By means of the gaseous intermediate container, the free volume V of the inner cavity of the first closed shell (4) when no object is suspended in the sample chamber (2) is obtained 自由 , and the method comprises injecting nitrogen into the gaseous intermediate container with a volume of V1, and the pressure of the nitrogen in the gaseous intermediate container is P1; then the gaseous intermediate container is connected with the inner cavity of the first closed shell (4), and the temperature of the gaseous intermediate container and the temperature of the inner cavity of the first closed shell (4) are both T1; the sample chamber gas inlet valve (8) is opened, the system pressure P2 after being connected is recorded, the nitrogen deviation factors Z1 and Z2 under the conditions of the temperature T1, the pressure P1 and the pressure P2 are obtained respectively, and V 自由' is calculated; A blank test was performed using helium to obtain the volume V of the sample basket (6) suspended in the first sealed shell (4). 篮 This includes evacuating the cavities of the first sealed shell (4) and the second sealed shell (11) respectively; then simultaneously injecting high-pressure helium into the cavities of the first sealed shell (4) and the second sealed shell (11). After the pressure inside the sealed shell stabilizes, the readings M of the first magnetic levitation balance (3) at multiple different injection pressure points are measured and recorded. 测 The reading M of the second magnetic levitation balance (10) 测2 and helium density ρ 氦气 According to the density ρ of helium 氦气 The reading M of the first magnetic levitation balance (3) after helium injection 测 The linear relationship is used to fit the mass M of the sample basket (6) in the Cartesian coordinate system. 篮 With volume V 篮 ; Put the elemental sulfur sample into the sample basket (6), use nitrogen for buoyancy test, get the initial volume V of the elemental sulfur sample 硫 And including putting the elemental sulfur sample into the sample basket (6), respectively, vacuumizing the inner cavities of the first closed shell (4) and the second closed shell (11); then injecting nitrogen into the first closed shell (4) and the second closed shell (11) simultaneously, after the gas in the first closed shell (4) and the second closed shell (11) reaches the equilibrium state, through the buoyancy test under different pressure points, get the readings M of the first magnetic levitation balance (3) under different pressure points 测 ’; the readings M of the second magnetic levitation balance (10) 测2 ’; according to the density ρ 氮气 of nitrogen and the readings M of the first magnetic levitation balance (3) under different pressure points after injecting nitrogen, in the Cartesian coordinate system, fitting to solve the initial mass M 测 and the initial volume V 硫 of the elemental sulfur sample 硫 Discharge the nitrogen in the first sealed shell (4) of the magnetic levitation sulfur solubility measuring instrument (1), and perform vacuumizing treatment on the cavities of the first sealed shell (4) and the second sealed shell (11); Injecting the sulfur-containing gas into the inner cavity of the first closed shell (4) and the second closed shell (11) respectively, performing sulfur solubility test, and obtaining the volume of elemental sulfur under different temperature and pressure conditions ; According to the density of the elemental sulfur sample , the internal cavity free volume V 自由 , the initial volume V 硫 of the elemental sulfur sample , the solubility of elemental sulfur in the sulfur-containing gas is calculated.

2. The method of claim 1, wherein, V The calculation formula is: 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 with the cavity of the first sealed 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.

3. The method of claim 1, wherein, Mass M of the sample basket (6) 篮 The calculation formula is: M 篮 =M 测 +ρ 氮气 × V 篮 ; M 已知 =M 测2 +ρ 氮气 × V 已知 ; where M 测 is the reading of the first magnetic levitation balance (3) in the sample chamber (2) at different pressure points; M 测2 is the reading of the second magnetic levitation balance (10) in the fluid chamber (9) at different pressure points; p 氦气 is the calculated helium density in the fluid chamber (9) at different pressure points; M 篮 is the mass of the sample basket (6); V 篮 is the volume of the sample basket (6); M 已知 is the mass of the standard object (13) of known volume and weight suspended in the closed cavity in the fluid chamber (9); V 已知 is the volume of the standard object (13) of known volume and weight suspended in the closed cavity in the fluid chamber (9).

4. The method of claim 1, wherein, The initial volume V of the elemental sulfur sample 硫 The formula for calculating is: M 硫 +M 篮 = M 测 ’+ρ 氮气 ×(V 篮 +V 硫 ); M 已知 =M 测2 ’+ρ 氮气 ×V 已知 ; where M 硫 is the initial mass of the elemental sulfur sample; V 硫 is the initial volume of the elemental sulfur sample.

5. The method of claim 1, wherein, The sulfur-containing gas is injected into the inner cavities of the first closed shell (4) and the second closed shell (11) respectively, a sulfur solubility test is performed, and the volume of elemental sulfur under different temperature and pressure conditions is obtained comprising: The temperature of the inner cavities of the first closed housing (4) and the second closed housing (11) is set to the target gas reservoir temperature T 温度 ; When the temperature of the target gas reservoir remains stable, open the sample chamber gas inlet valve (8) and the fluid chamber gas inlet valve (15) respectively, and inject the prepared sulfur-containing gas into the cavities of the first sealed shell (4) and the second sealed shell (11) respectively, and the injection pressure is set as P1; When the pressure in the inner cavities of the first closed housing (4) and the second closed housing (11) is stabilized, the reading M of the first magnetic levitation balance (3) and the reading of the second magnetic levitation balance (10) are recorded, respectively 硫测 ;​ Obtain the density of the sulfur-containing gas through the second magnetic levitation balance (10): ； wherein T is the temperature i the density of the sulphur-containing gas sample when the second magnetic levitation balance (10) is read at different pressures of the sulphur-containing gas, T is the temperature of the gas reservoir and P is the pressure of the sulphur-containing gas in the inner chamber of the second closed housing (11) i the density of the sulphur-containing gas sample when the second magnetic levitation balance (10) is read at different pressures of the sulphur-containing gas, According to the force analysis of the first magnetic levitation balance (3), there is the following relationship: ； wherein M 硫测 is the reading of the first magnetic levitation balance (3) at temperature T i and at a pressure P i of the sulfur-containing gas in the inner cavity of the first closed housing (4), is the reading of the first magnetic levitation balance (3) at temperature T i and at a pressure P i of the sulfur-containing gas in the inner cavity of the first closed housing (4), is the volume of the residual elemental sulfur sample after saturation dissolution of the elemental sulfur crystal into the sulfur-containing gas at temperature T i and at a pressure P i of the sulfur-containing gas in the inner cavity of the first closed housing (4). Due to ; Then the above formula can be changed to: ； Then further: 。 6. The method of claim 1, wherein, said density of the elemental sulfur sample , the free volume V of the inner cavity of said first closed housing (4) when not suspended with any object 自由 , the initial volume V of said elemental sulfur sample 硫 , and the residual volume of elemental sulfur after dissolution in the sulfur-containing gas , the solubility of elemental sulfur in the sulfur-containing gas is calculated as: ​ 。 7. The method of claim 1, wherein, The device further comprises a sample chamber gas inlet valve (8) arranged outside the sample chamber (2), a fluid chamber gas inlet valve (15) arranged outside the fluid chamber (9), and a gas inlet pipeline total valve (17), the sample chamber gas inlet valve (8), the fluid chamber gas inlet valve (15) and the gas inlet pipeline total valve (17) are all connected with the gas inlet pipeline (16).

8. The method according to claim 1 or 7, characterized in that, The first pressure measurement system and the temperature control system (7) are arranged at the bottom of the cavity of the first sealed shell (4); the second pressure measurement system and the temperature control system (14) are arranged at the bottom of the cavity of the second sealed shell (11); the first magnetic levitation balance (3) is arranged above the first sealed shell (4); and the second magnetic levitation balance (10) is arranged above the second sealed shell (11).

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