CN102053055B - High-temperature high-pressure multifunctional core sulfur deposition test device and method - Google Patents

Abstract

The invention discloses high-temperature high-pressure multifunctional core sulfur deposition test device and method. The sulfur deposition test device comprises a displacement system, a formation condition analog system, a data acquisition system and a data processing system. The sulfur deposition test method comprises the following steps of: constructing a test environment, measuring the sulfur element deposition on line, observing the sulfur element deposition process on line, and testing the change of permeability of a rock sample before and after sulfur deposition and the like. The invention has the beneficial effects of realizing the visual display of a true core sulfur deposition process, the real-time online measurement of the sulfur deposition and dynamic calculation of core permeability change caused by sulfur deposition and accurately and dynamically evaluating the damage severity of permeability of a reservoir stratum, caused by sulfur deposition in real time, and has the advantages of high degree of automation, good safety, high accuracy, high temperature and high pressure resistance, strong corrosion resistance and the like.

Description

High temperature and high pressure multifunctional core sulfur deposition testing device and method

technical field

The invention relates to a sulfur deposition testing device and method, in particular to a high-temperature, high-pressure multifunctional rock core sulfur deposition testing device and method.

Background technique

High-sulfur gas reservoirs are widely distributed around the world, such as the Murray Franklin gas field in Texas, the Bentz/Bearberry gas field in Alberta, Canada, the Panther River gas field, the Black/Josephine gas field in Mississippi, the Cox gas field, and the continental facies in the Bohai Bay Basin in China. Zhaolanzhuang Gas Field in North China, Luojia Gas Field in Shengli Oilfield, Feixianguan Formation Gas Pool in Dukouhe Gas Field in Sichuan Basin, Feixianguan Formation Gas Pool in Luojiazhai Gas Field, Feixianguan Formation Gas Pool in Puguang Gas Field, Tieshanpo Gas Field in the Sichuan Basin Gas reservoirs in the Feixianguan Formation of the Gas Field, the Feixianguan Formation of the Longmen Gas Field, the Feixianguan Formation of the Gaofengchang Gas Field, the Leikoupo Formation of the Zhongba Gas Field, and the Jialingjiang Formation of the Wolonghe Gas Field are all typical high Sulfur-bearing reservoirs. Due to the existence of H ₂ S, the production characteristics of high-sulfur gas reservoirs are quite different from those of conventional gas reservoirs. During the production of gas from high-sulfur gas reservoirs, as the gas is produced, the formation pressure continues to drop, and elemental sulfur will be precipitated from the sulfur-carrying gas in the form of monomer, and will exist in the form of solid sulfur under appropriate temperature conditions. And deposit in the pore throats of reservoir rocks, thereby blocking the seepage channels of natural gas, reducing the effective pore space and permeability of the formation, and affecting gas production capacity. Insufficient understanding of gas reservoir development resulted in severe elemental sulfur deposition, forcing the well to be shut down and has not yet been put into production. Foreign JB Hyne and GDDerdall (1980) reported examples of elemental sulfur deposition in Germany, the United States, Canada and other countries. Once the formation temperature is lower than the melting point of elemental sulfur, elemental sulfur will be deposited, which will significantly reduce gas production, even if elemental sulfur remains in a liquid state. , due to its high viscosity, it will also reduce the gas production. BERoberts (1996) and ^Nacholas Hands (2002) studied the depositional characteristics of elemental sulfur in the Foothills sour gas field in the Rocky Mountains region of Shell Canada. "Sulfur blockage" occurs, resulting in the failure of normal production. It can be seen that the prediction and evaluation technology of sulfur deposition is very important for the development of high-sulfur gas reservoirs. The research is almost at a blank stage, and due to the large difference between the experimental conditions of sulfur deposition evaluation and the actual formation seepage conditions, the existing experimental testing methods cannot accurately and dynamically evaluate the damage degree of sulfur deposition to the permeability of reservoir rock samples in real time.

Contents of the invention

The purpose of the present invention is to overcome the deficiencies of the prior art, and provide a high-temperature, high-pressure multifunctional rock core sulfur deposition testing device and method. The device uses advanced computer measurement and control technology and sensor technology to visually capture the formation process of sulfur deposition in real rock samples, test the amount of sulfur deposition online, dynamically calculate the changes in rock sample permeability and other physical properties caused by sulfur deposition, and dynamically evaluate the impact of sulfur deposition in real time. Effects of reservoir damage.

The object of the present invention is achieved by the following technical solutions: a high temperature and high pressure multifunctional core sulfur deposition testing device, which includes a displacement system, a stratum condition simulation system, a data acquisition system and a data processing system.

The displacement system includes a sampler, a sampler, a gas booster pump, a constant-speed constant-pressure pump and an intermediate container. The sampling port of the sampler is connected to the inlet of the sampler through a pipeline, and the outlet of the gas booster pump is also Connect to the sample inlet of the sampler through the pipeline; the outlet of the constant speed and constant pressure pump is connected to the lower inlet of the intermediate container through the pipeline, and the outlet of the gas booster pump is also connected to the upper inlet of the intermediate container through the pipeline. The outlets of the device and the intermediate container are connected with the formation condition simulation system through pipelines. The constant speed and constant pressure pump is used to provide continuous non-pulse displacement of the fluid, and can work at constant speed and constant pressure; the intermediate container is a piston type, used to store high hydrogen sulfide gas samples, and the piston of the intermediate container is driven by the constant speed and constant pressure pump , to displace the high hydrogen sulfide gas sample placed in the intermediate container to the core holder or high-pressure window; the sampler is used for sample preparation of the test medium; The sample is mixed in the sampler. The gas booster pump can pressurize the sample in the sampler and the intermediate container to achieve the required formation conditions.

The formation condition simulation system includes a constant temperature box, a core holder and a high pressure window. Both the core holder and the high-pressure viewing window are placed in the constant temperature box, and the sample inlets of the core holder and the high-pressure viewing window are connected with the outlet of the sample dispenser and the intermediate container through the input pipeline. The core holder is used for the determination of the sulfur deposition amount of the rock sample and the determination of the permeability parameter of the rock sample. The core holder is made of titanium alloy, which requires high strength and light weight, and is used for online weighing; the function of the thermostat is to provide formation temperature conditions for the test; the high-pressure window is used for online observation and photographing of the sulfur deposition process. A high-magnification camera is installed outside the high-pressure window, which can effectively observe the sulfur deposition process in the sand filling model.

The high-pressure window includes an upper gland, a lower gland, an air inlet, an air outlet, a sand filling chamber, an observation window and a support frame, the sand filling chamber is fixed on the support frame, and the air inlet and the air outlet are respectively located at the The two ends of the sand cavity are connected together, the observation window is located above the sand filling cavity, and the upper gland and the lower gland are fixed on the upper and lower parts of the support frame by bolts.

The data acquisition system includes at least two pressure sensors, temperature sensors, on-line measuring balances and high-definition cameras. The pressure sensors are respectively placed in the input pipeline and output pipeline of the core holder, the probe of the temperature sensor is placed in the middle of the thermostat, and the core The holder is suspended on the hook at the lower end of the online measuring balance, the high-definition camera is placed outside the thermostatic chamber, and the output of the pressure sensor, temperature sensor, online measuring balance and high-definition camera are respectively connected to the data processing system. The pressure sensor and temperature sensor are used to measure the pressure at both ends of the core holder and the temperature in the thermostat respectively, and the online metering balance is used to measure the sulfur deposition in the rock sample in real time when the gas with high hydrogen sulfide content flows through the core holder ;The high-definition camera is installed behind the incubator, and the sand-filling model is photographed through the visible window, and the shooting is controlled by computer control software.

The data processing system includes at least one computer, a data acquisition board and a video acquisition card placed in the computer, and data processing software running on the computer. The computer communicates with the pressure sensor, the temperature sensor and the online The output connection of the measuring balance, the computer is connected with the output of the high-definition camera through the video capture card. The data processing software on the computer calculates the amount of sulfur deposition based on the data collected by the online metering balance, and the video processing software on the computer controls the capture action of the high-definition camera, and saves and displays the captured images.

The displacement system also includes two hand pumps and a back pressure valve, the outlet of the hand pump is respectively connected to the confining pressure port of the core holder and the control port of the back pressure valve through pipelines. The input port of the back pressure valve is connected with the core holder and the output pipeline of the high pressure window, and the output port of the back pressure valve is connected with the interface of the separator. Among the two hand pumps, one is used to provide confining pressure for the rock sample in the core holder, and the other is used to provide back pressure for the back pressure valve. Stable pressure to improve metering accuracy.

The data acquisition system also includes a high-precision balance and a separator, the high-precision balance is connected with the separator, and the separator is connected with the back pressure valve. High-precision balances are used to measure liquid flow.

The data acquisition system also includes at least one flowmeter, and the flowmeter is one or more of a large-range flowmeter, a medium-range flowmeter, or a small-range flowmeter. The inlet of the flowmeter is connected to the gas outlet of the separator through pipelines, the separator is connected to the back pressure valve, the outlet of the flowmeter is connected to the neutralization tank through the discharge pipeline, and the signal system of the flowmeter is connected to the data acquisition board.

Both the incubator and the sample dispenser are provided with an isolated toughened glass cover, and the upper end of the glass cover is provided with a hydrogen sulfide gas leakage alarm device and an explosion-proof exhaust fan. Because hydrogen sulfide gas is highly toxic, the present invention has carried out safety protection measures for the entire experimental environment, that is, an isolation tempered glass cover is installed outside the incubator and the sampler, and an explosion-proof exhaust fan is installed on the upper end of the glass fiber reinforced plastic cover to dissipate the toxic gas. Empty to the hydrogen sulfide gas absorption tower for treatment.

The incubator is heated by a fully enclosed electric heating tube. Since hydrogen sulfide is a flammable and explosive gas, it has very strict requirements on the environment and electric sparks are not allowed. Therefore, the constant temperature box of the present invention adopts the hot air convection circulation mode, and provides the required heat through the heating of the fully enclosed electric heating tube, and adopts The fan generates circulating air to form heat convection.

Each section of the pipeline of the high temperature and high pressure multifunctional rock core sulfur deposition testing device described in the present invention is provided with a regulating valve, and a safety valve is provided in the input pipeline, and the described rock core holder is provided with a vent valve. The outlet is connected to the external neutralization tank through the discharge pipeline. The adjustment valve is beneficial to control and maintenance. Since the toxic hydrogen sulfide gas cannot be discharged directly, the outlet of the vent valve is connected to the external neutralization tank through the discharge pipeline. In the neutralization tank, the Toxic gas is neutralized, and the purpose of setting the safety valve is to automatically release the pressure when the pressure is overloaded, and realize multiple pressure overload protection for the pump and pressure sensor, so as to ensure the safety of test personnel and equipment.

A method for testing sulfur deposition on a high-temperature, high-pressure multifunctional rock core, comprising the following steps:

(1) Test environment construction: establish a test environment consisting of a displacement system, a formation condition simulation system, a data acquisition system and a data processing system;

(2) On-line measurement of elemental sulfur deposition: Before the sour gas sample is passed through, the net weight of the core holder containing the rock sample is firstly measured by an online metering balance. Then open the valve, inject the high hydrogen sulfide-containing gas sample in the sampler or the intermediate container into the rock sample, continuously reduce the internal temperature or pressure of the core holder, and measure the weight of the core holder of the sedimentary rock sample containing elemental sulfur on-line. The difference with the net weight is the deposition of elemental sulfur;

(3) On-line observation of elemental sulfur deposition process: Let the high-pressure hydrogen sulfide gas sample flow through the high-pressure window, and the high-definition camera will take pictures of the high-pressure window deposition process through the visible window of the incubator, and take pictures continuously under the control of the computer;

(4) Permeability change test before and after sulfur deposition: Before the acid gas sample is passed through, the absolute permeability of the rock sample is tested with nitrogen gas, and then the high hydrogen sulfide gas sample in the sample dispenser or the intermediate container is injected into the rock sample, continuously Reduce the internal temperature or pressure of the core holder, and at the same time dynamically measure the pressure at both ends of the elemental sulfur-containing sedimentary rock sample, calculate the viscosity, volume coefficient and deviation factor of the gas in real time, and then calculate the gas of the elemental sulfur-containing sedimentary rock sample in real time according to Darcy's law Measure the permeability and dynamically evaluate the damage degree of sulfur deposition to the permeability of rock samples.

The calculation formula of rock sample gas permeability is as follows:

${\mathrm{<span\; class="notranslate">\; K</span>}}_{\mathrm{<span\; class="notranslate">\; g</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; Q</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}{\mathrm{<span\; class="notranslate">\; \&mu;</span>}}_{\mathrm{<span\; class="notranslate">\; g</span>}}{\mathrm{<span\; class="notranslate">\; LZ</span>}}_{\mathrm{<span\; class="notranslate">\; a</span>}}}{\mathrm{<span\; class="notranslate">\; A</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; <figure-callout\; id="2"\; label="P"\; filenames="101203204122.png"\; state="\{\{state\}\}">P</figure-callout></span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; Z</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

Z _a —coefficient of gas variation under test pressure and test temperature, decimal;

Z ₀ —— gas deviation coefficient under standard conditions, decimal;

K _g — gas permeability, um ² ;

Q ₀ ——gas flow rate under standard conditions, cm ³ /s;

L——rock sample length, cm;

A—cross-sectional area of rock sample, cm ² ;

P ₀ ——atmospheric pressure under standard conditions, atm;

P ₁ ——rock sample inlet pressure, atm;

P ₂ ——rock sample outlet pressure, atm;

μ _g —gas viscosity at test pressure and test temperature, mPa.s.

The deviation coefficient Z _a in formula (1) can be calculated by Guo Xuqiang correction method and Wichert-Aziz correction method, both of which are to correct the critical parameters of the gas sample, and then use the HTP and DPR models to calculate the mixed gas deviation coefficient.

1) The Guo Xuqiang correction method corrects the critical parameters of the gas sample as follows:

T _c ＝ T _m -C _wa (2)

p _c ＝T _c ∑(x _i p _ci )/[T _c +x ₁ (1-x ₁ )C _wa ] (3)

${\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}}<span\; class="notranslate">\; =</span>\underset{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\overset{\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; ci</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 4</span>}<span\; class="notranslate">\; )</span>$

${\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; w</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; 14.5038</span>}}<span\; class="notranslate">\; |</span>\mathrm{<span\; class="notranslate">\; 120</span>}<span\; class="notranslate">\; \&times;</span><span\; class="notranslate">\; |</span>{<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 0.9</span>}}<span\; class="notranslate">\; -</span>{<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 1.6</span>}}<span\; class="notranslate">\; |</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 15</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; 0</span>}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; 5</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; |</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 5</span>}<span\; class="notranslate">\; )</span>$

In the formula: x ₁ is the mole fraction of H ₂ S in the system;

_x2 is the mole fraction of _CO2 in the system.

2) The Wichert-Aziz correction method corrects the critical parameters of the gas sample as follows:

T′ _ci = T _ci -ε (6)

p' _ci = p _ci T' _ci /T _ci (7)

ε＝15(MM ² )+4.167(N ^0.5 -N ² ) (8)

In the formula: T _ci is the critical temperature of component i, K;

P _ci is the critical pressure of component i, KPa;

T _ci ' is the corrected critical temperature of component i, in K;

P _ci ' is the corrected critical pressure of component i, in KPa.

M is the sum of the mole fractions of _H2S and _CO2 in the gas mixture;

N is the mole fraction of _H2S in the gas mixture.

The mixed gas viscosity calculation model in formula (1) adopts the correction formula proposed by Standing as follows:

${\mathrm{<span\; class="notranslate">\; \&mu;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}^{<span\; class="notranslate">\; \&prime;</span>}<span\; class="notranslate">\; =</span>{<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; \&mu;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span>}_{\mathrm{<span\; class="notranslate">\; un</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; \&mu;</span>}}_{{\mathrm{<span\; class="notranslate">\; <figure-callout\; id="2"\; label="N"\; filenames="101203204122.png"\; state="\{\{state\}\}">N</figure-callout></span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; \&mu;</span>}}_{{\mathrm{<span\; class="notranslate">\; <figure-callout\; id="2"\; label="CO"\; filenames="101203204122.png"\; state="\{\{state\}\}">CO</figure-callout></span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; \&mu;</span>}}_{{\mathrm{<span\; class="notranslate">\; h</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}\mathrm{<span\; class="notranslate">\; S</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 9</span>}<span\; class="notranslate">\; )</span>$

The correction coefficients in the formula are:

${\mathrm{<span\; class="notranslate">\; \&mu;</span>}}_{{\mathrm{<span\; class="notranslate">\; h</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}\mathrm{<span\; class="notranslate">\; S</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; h</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}\mathrm{<span\; class="notranslate">\; S</span>}<span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 8.49</span>}<span\; class="notranslate">\; \&times;</span>{\mathrm{<span\; class="notranslate">\; 10</span>}}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 3</span>}}\mathrm{<span\; class="notranslate">\; lg</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; g</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 3.73</span>}<span\; class="notranslate">\; \&times;</span>{\mathrm{<span\; class="notranslate">\; 10</span>}}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 10</span>}<span\; class="notranslate">\; )</span>$

${\mathrm{<span\; class="notranslate">\; \&mu;</span>}}_{{\mathrm{<span\; class="notranslate">\; <figure-callout\; id="2"\; label="CO"\; filenames="101203204122.png"\; state="\{\{state\}\}">CO</figure-callout></span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; <figure-callout\; id="2"\; label="CO"\; filenames="101203204122.png"\; state="\{\{state\}\}">CO</figure-callout></span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 9.08</span>}<span\; class="notranslate">\; \&times;</span>{\mathrm{<span\; class="notranslate">\; 10</span>}}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 3</span>}}\mathrm{<span\; class="notranslate">\; lg</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; g</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 6.24</span>}<span\; class="notranslate">\; \&times;</span>{\mathrm{<span\; class="notranslate">\; 10</span>}}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 11</span>}<span\; class="notranslate">\; )</span>$

${\mathrm{<span\; class="notranslate">\; \&mu;</span>}}_{{\mathrm{<span\; class="notranslate">\; <figure-callout\; id="2"\; label="N"\; filenames="101203204122.png"\; state="\{\{state\}\}">N</figure-callout></span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; <figure-callout\; id="2"\; label="N"\; filenames="101203204122.png"\; state="\{\{state\}\}">N</figure-callout></span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 8.48</span>}<span\; class="notranslate">\; \&times;</span>{\mathrm{<span\; class="notranslate">\; 10</span>}}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 3</span>}}\mathrm{<span\; class="notranslate">\; lg</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; g</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 9.59</span>}<span\; class="notranslate">\; \&times;</span>{\mathrm{<span\; class="notranslate">\; 10</span>}}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 12</span>}<span\; class="notranslate">\; )</span>$

为硫化氢粘度校正值，mPa·s；In the formula:

is the corrected value of hydrogen sulfide viscosity, mPa·s;

为二氧化碳粘度校正值，mPa·s；

is the correction value of carbon dioxide viscosity, mPa·s;

为氮气粘度校正值，mPa·s；

is the correction value of nitrogen viscosity, mPa·s;

N ₂ , CO ₂ , H ₂ S are the molar contents of the gas mixture, decimals;

γ _g is the relative density of natural gas (air=1.0);

T is formation temperature, °C.

The working process of the high temperature and high pressure multifunctional rock core sulfur deposition testing device of the present invention is as follows:

1) Turn on the system control power supply, the system is in the standby state, press the lighting button, inlet and outlet pressure buttons;

2) Take out the core holder from the incubator, open it and put it into the rock sample to be tested;

3) Put the core holder into the constant temperature box, connect the pipeline, first use the hand pump to press the rock sample in the core holder firmly, and then apply the set confining pressure; at the same time, use another hand pump to add corresponding back pressure;

4) Close the door of the incubator, press the fan and heating button, and set the corresponding temperature; after a period of heating, the set temperature is reached, and it needs to be stabilized for a period of time, so that the long core holder or the high-pressure window can fully perform heat exchange , so that its temperature reaches the system setting value. (Note: Be sure to turn on the fan first, and then turn on the heating, otherwise local heating will easily cause system damage!);

5) Measurement of the absolute permeability of the rock sample before sulfur deposition: Before passing the acid gas sample, under a certain P and T, nitrogen gas is first passed through the core holder, and the rock sample is calculated according to the gas flow rate and the pressure difference between the two ends of the rock sample. Absolute permeability;

6) Measurement of rock sample permeability after sulfur deposition: Inject the high-hydrogen sulfide gas sample in the sample dispenser or intermediate container into the rock sample, continuously reduce the internal temperature or pressure of the core holder, and measure the elemental sulfur deposition in the rock sample online , and at the same time dynamically measure the pressure at both ends of the elemental sulfur-containing sedimentary rock sample. Then, according to the gas composition and the temperature and pressure of the system, the viscosity μ _g , the volume coefficient B _g and the deviation factor Z _a of the gas are calculated in real time. Then, according to the calculation program, the gas permeability value under the corresponding conditions is calculated in real time, and automatically saved in the corresponding file.

7) On-line observation of the elemental sulfur deposition process: let the high-hydrogen sulfide-containing gas sample flow through the high-pressure window, and the high-definition camera will take pictures of the sulfur deposition process in the high-pressure window through the visible window of the incubator, and take pictures continuously at regular intervals under computer control;

8) After the experimental test is completed, open the anti-air valve to vent to the neutralization tank to process the high-hydrogen sulfide gas sample, and repeatedly flush the system with nitrogen to prevent natural gas from corroding the pipeline. (Note: Before closing the experimental system, be sure to turn off the heating and then the fan to fully dissipate heat, otherwise it will cause damage to the system!);

9) Organize the laboratory instruments and put the instruments back in place for the next use.

The beneficial effects of the present invention are: realizing the visual display of the formation process of sulfur deposition in real cores, the real-time online measurement of sulfur deposition and the dynamic calculation of the change of core permeability caused by sulfur deposition, and the ability to dynamically simulate and evaluate the damage degree of sulfur deposition to reservoirs , has the advantages of high degree of automation, good safety, high accuracy, high temperature and high pressure resistance, and strong corrosion resistance. The temperature and pressure can be as high as 150°C and 70MPa respectively.

Description of drawings

Fig. 1 overall composition structure schematic diagram of the present invention

Fig. 2 data acquisition and control structure schematic diagram of the present invention

Figure 3 Schematic diagram of the structure of the high-voltage window

In the figure, 1-sampler, 2-sample dispenser, 3-gas booster pump, 4-constant speed and constant pressure pump, 5-intermediate container, 6-constant temperature box, 7-core holder, 8-high pressure window , 9-pressure sensor, 10-on-line measurement balance, 11-high-precision balance, 12-high-definition camera, 13-large-range flowmeter, 14-data acquisition board, 15-computer, 16-video acquisition card, 17-hand crank Pump, 18-back pressure valve, 19-regulating valve, 20-vent valve, 21-safety valve, 22-separator, 23-medium range flowmeter, 24-small range flowmeter, 25-temperature sensor. 26-upper gland, 27-lower gland, 28-air inlet, 29-air outlet, 30-sand filling cavity, 31-observation window, 32-support frame.

Detailed ways

The technical scheme of the present invention is further described below in conjunction with accompanying drawing: Fig. 1 high temperature and high pressure multifunctional rock core sulfur deposition testing device, it comprises displacement system, stratum condition simulation system, data acquisition system and data processing system.

The displacement system includes a sampler 1, a sampler 2, a gas booster pump 3, a constant speed and constant pressure pump 4, an intermediate container 5, a hand pump 17 and a back pressure valve 18, and the sampling port of the sampler 1 passes through The pipeline is connected to the sampling port of the sampler 2, and the outlet of the gas booster pump 3 is also connected to the sampling port of the sampler 2 through the pipeline; the outlet of the constant speed and constant pressure pump 4 is connected to the intermediate container 5 through the pipeline The outlet of the gas booster pump is also connected to the upper inlet of the intermediate container through the pipeline, the outlet of the sampler 2 and the intermediate container 5 is connected with the formation condition simulation system through the pipeline, and the outlet of the hand pump 17 is connected through the pipeline The road is respectively connected with the confining pressure port of the core holder 7 and the control port of the back pressure valve 18, the input port of the back pressure valve 18 is connected with the output pipeline of the rock core holder 7 and the high pressure window 8, and the back pressure valve 18 The output port is connected to the interface of the separator 22, the outside of the sample dispenser 2 is provided with an isolated toughened glass cover, and the intermediate container 5 is a piston container.

The formation condition simulation system includes a constant temperature box 6, a rock core holder 7 and a high-pressure window 8, and the rock core holder 7 and the high-pressure window 8 are all placed in the constant temperature box 6, and the sample injection of the rock core holder 7 and the high-pressure window 8 The port is connected with the outlet of the sampler 2 and the upper inlet of the intermediate container 5 through the input pipeline, and each section of the pipeline of the whole device is provided with a regulating valve 19, and the input pipeline is equipped with a safety valve 21. The rock core The holder 7 is provided with a vent valve 20, and the outlet of the vent valve 20 is connected to an external neutralization tank through a discharge pipeline. The thermostat 6 is heated by a fully enclosed electric heating tube. Equipped with hydrogen sulfide gas leakage alarm device and explosion-proof exhaust fan.

In order to improve corrosion resistance, all pipe parts in contact with hydrogen sulfide gas are made of sulfur-resistant Hastelloy material.

Described data acquisition system comprises at least two pressure sensors 9, temperature sensor 25, online measuring balance 10, high-precision balance 11, large range flowmeter 13, medium range flowmeter 23, small range flowmeter 24, separator 22 and The high-definition camera 12, the pressure sensor 9 are respectively placed in the input pipeline and the output pipeline of the core holder 7, the probe of the temperature sensor 25 is placed in the middle of the thermostat 6, and the core holder 7 is suspended from the lower end of the online measuring balance 10 On the hook, the high-definition camera 12 is placed outside the incubator 6, the output of the pressure sensor 9, the temperature sensor 25, the online measurement balance 10 and the high-definition camera 12 are respectively connected with the data processing system, and the high-precision balance 11 is connected with the separator 22, The inlets of the large-range flowmeter 13, the medium-range flowmeter 23 and the small-range flowmeter 24 are all connected to the gas outlet of the separator 22 through pipelines, and the outlets are connected to the neutralization tank through the discharge pipeline. The data acquisition board (14) is connected.

As Fig. 2, described data processing system comprises at least one computer 15, puts the data acquisition board 14 and video acquisition card 16 in the computer 15 and runs on the data processing software on the computer 15, computer 15 passes data acquisition board 14 The multi-channel acquisition ports of the multi-channel are respectively connected with the output of the pressure sensor 9, the temperature sensor 25, the outlet measuring balance 11, the online measuring balance 10, the large-range flowmeter 13, the medium-range flowmeter 23 and the small-range flowmeter 24, and the computer 15 passes the video The capture card 16 is connected with the output of the high-definition camera 12 .

As shown in Figure 3, the high-pressure window 8 includes an upper gland 26, a lower gland 27, an air inlet 28, an air outlet 29, a sand filling cavity 30, an observation window 31 and a support frame 32, and the sand filling cavity 30 is fixed on the support frame 32, the air inlet 28 and the air outlet 29 are respectively located at the two ends of the sand filling chamber 30 and connected, the observation window 31 is located above the sand filling chamber 30, and the upper gland 26 and the lower gland 27 are fixed on the support frame by bolts 32 upper and lower parts.

A method for testing sulfur deposition on a high-temperature, high-pressure multifunctional rock core, comprising the following steps:

(1) Test environment construction: establish a test environment consisting of a displacement system, a formation condition simulation system, a data acquisition system and a data processing system;

(2) On-line measurement of elemental sulfur deposition: before the sour gas sample is passed, at first adopt the on-line metering balance 10 to measure the net weight of the rock core holder 7 containing the rock sample, then open the valve, and the high The gas sample containing hydrogen sulfide is injected into the rock sample, the internal temperature or pressure of the core holder 7 is continuously reduced, and the weight of the core holder of the sedimentary rock sample containing elemental sulfur is measured online, and the difference between it and the net weight is the deposition amount of elemental sulfur;

(3) On-line observation of the elemental sulfur deposition process: let the high-pressure hydrogen sulfide gas sample flow through the high-pressure window 8, and the high-definition camera will take pictures of the sulfur deposition process in the high-pressure window through the window of the thermostat 6, and take regular and continuous snapshots under the control of the computer 15 picture;

(4) Permeability change test before and after sulfur deposition: Before the acid gas sample is passed through, the absolute permeability of the rock sample is tested with nitrogen gas, and then the high hydrogen sulfide gas sample in the sample dispenser 2 or the intermediate container 5 is injected into the rock sample , continuously reducing the internal temperature or pressure of the core holder 7, and at the same time dynamically measuring the pressure at both ends of the elemental sulfur-containing sedimentary rock sample, and calculating the viscosity, volume coefficient and deviation factor of the gas in real time. Then, according to Darcy's law, the gas permeability of the elemental sulfur-containing sedimentary rock sample is calculated in real time, and the damage degree of sulfur deposition to the rock sample permeability is dynamically evaluated.

Claims (1)

1. High temperature and high pressure multifunctional core sulfur deposition testing device, characterized in that it includes a displacement system, a formation condition simulation system, a data acquisition system and a data processing system; The displacement system includes a sampler (1), a sampler (2), a gas booster pump (3), a constant-speed constant-pressure pump (4) and an intermediate container (5), and the sampling of the sampler (1) The outlet of the gas booster pump (3) is connected to the sample inlet of the sampler (2) in parallel through the pipeline; the constant speed and constant pressure pump (4) The outlet of the gas booster pump (3) is also connected to the upper inlet of the intermediate container (5) through a pipeline, the sampler (2) and the intermediate container (5) ) outlet is connected to the formation condition simulation system through pipelines; The formation condition simulation system includes a constant temperature box (6), a core holder (7) and a high-pressure window (8), and the core holder (7) and the high-pressure window (8) are placed in the constant temperature box (6), The sample inlet of the core holder (7) and the high-pressure window (8) is connected with the outlet of the sampler (2) of the displacement system and the upper inlet of the intermediate container (5) through pipelines; The high-pressure window (8) includes an upper gland (26), a lower gland (27), an air inlet (28), an air outlet (29), a sand filling cavity (30), an observation window (31) and a support frame (32), the sand filling chamber (30) is fixed on the support frame (32), the air inlet (28) and the air outlet (29) are respectively located at the two ends of the sand filling chamber (30) and communicated, the observation window (31) Located above the sand filling cavity (30), the upper gland (26) and the lower gland (27) are fixed to the upper and lower parts of the support frame (32) by bolts; The data acquisition system includes at least two pressure sensors (9), temperature sensors (25), online weighing balances (10) and high-definition cameras (12), and the pressure sensors (9) are respectively placed in the core holder (7) The input pipeline and output pipeline, the probe of the temperature sensor (25) is placed in the middle of the incubator (6), the core holder (7) is suspended on the hook at the lower end of the online weighing balance (10), and the high-definition camera (12) Placed outside the incubator (6), the outputs of the pressure sensor (9), temperature sensor (25), on-line measurement balance (10) and high-definition camera (12) are respectively connected to the data processing system; The data processing system includes at least one computer (15), a data acquisition board (14) and a video acquisition card (16) placed in the computer (15), and data processing software running on the computer (15). (15) Connect the multi-channel acquisition port of the data acquisition board (14) to the output of the pressure sensor (9), temperature sensor (25) and online measurement balance (10), and the computer (15) through the video acquisition card (16) Connect with the output of HD camera (12). 2. The high temperature and high pressure multifunctional core sulfur deposition testing device according to claim 1, characterized in that: the displacement system further includes two hand pumps (17) and a back pressure valve (18), the hand pump ( The outlet of 17) is respectively connected with the confining pressure port of the core holder (7) and the control port of the back pressure valve (18) through pipelines; the input port of the back pressure valve (18) is connected with the core holder (7) and the control port of the back pressure valve (18). The output pipeline of the high-pressure window (8) is connected, and the output port of the back pressure valve (18) is connected with the interface of the separator (22). 3. The high-temperature, high-pressure multifunctional rock core sulfur deposition testing device according to claim 2, characterized in that: the data acquisition system also includes a high-precision balance (11), a high-precision balance (11) and a separator (22) connect. 4. The high-temperature, high-pressure multifunctional rock core sulfur deposition test device according to claim 2, characterized in that: the data acquisition system further includes at least one flowmeter, the flowmeter is a large-range flowmeter (13), a medium-range flowmeter meter (23) or small range flow meter (24) or one or more; the inlet port of the flow meter is connected to the gas outlet port of the separator (22) through the pipeline, and the outlet port of the flow meter is connected to the gas outlet port through the discharge pipeline. The neutralization pool, the signal system of the flowmeter is connected with the data acquisition board (14). 5. The high temperature and high pressure multifunctional core sulfur deposition testing device according to claim 1, characterized in that: the outside of the thermostat box (6) and the sample dispenser (2) are equipped with an isolation toughened glass cover, and the upper end of the glass cover is set There are hydrogen sulfide gas leakage alarm devices and explosion-proof exhaust fans. 6. The high-temperature, high-pressure multifunctional rock core sulfur deposition testing device according to claim 1, characterized in that: the constant temperature box (6) is heated by a fully-sealed electric heating tube. 7. The high temperature and high pressure multifunctional rock core sulfur deposition testing device according to claim 1, characterized in that: each section of the pipeline of the whole device is equipped with a regulating valve (19), and the input pipeline is equipped with a safety valve (21), The core holder (7) is provided with a vent valve (20), and the outlet of the vent valve (20) is connected to an external neutralization tank through a discharge pipeline. 8. The high temperature and high pressure multifunctional rock core sulfur deposition testing method is characterized in that it comprises the following steps: ① Test environment construction: establish a test environment based on the composition of the displacement system, formation condition simulation system, data acquisition system and data processing system described in claim 1; ② On-line measurement of elemental sulfur deposition: before the sour gas sample is passed through, the online weighing balance (10) is used to measure the net weight of the core holder (7) containing the rock sample, and then the valve is opened, and the sample dispenser (2) or the intermediate container The high hydrogen sulfide-containing gas sample in (5) is injected into the rock sample, the internal temperature or pressure of the core holder (7) is continuously reduced, and the weight of the core holder of the sedimentary rock sample containing elemental sulfur is measured online, and the difference between it and the net weight is the amount of elemental sulfur deposited; ③ On-line observation of elemental sulfur deposition process: Let the high-pressure hydrogen sulfide gas sample flow through the high-pressure window (8), and the high-definition camera will record the sulfur deposition process in the high-pressure window through the visible window of the thermostat (6), and control it under the control of the computer (15) Continuously capture pictures at regular intervals; ④ Permeability change test before and after sulfur deposition: Before passing the acid gas sample, test the absolute permeability of the rock sample with nitrogen gas, and then inject the high hydrogen sulfide gas sample in the sampler (2) or the intermediate container (5) into the rock sample. During the sample, the internal temperature or pressure of the core holder (7) is continuously reduced, and at the same time, the pressure at both ends of the sedimentary rock sample containing elemental sulfur is dynamically measured, and the viscosity, volume coefficient and deviation factor of the gas are calculated in real time, and then calculated in real time according to Darcy's law Gas permeability of sedimentary rock samples containing elemental sulfur, and dynamically evaluate the damage degree of sulfur deposition to rock sample permeability.

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