Gas Ratio Research Articles

Outgassing Characteristics of Ceramic Shell Material and Microchannel Plates of Third-Generation Low-Light-Level Image Intensifiers

Vacuum failure is a major cause of shortening the lifetime (especially storage lifetime) of low-light-level image intensifiers. In order to deeply understand the vacuum failure mechanism of image intensifiers, the gas releasing rates and compositions of ceramic shell material (95 alumina ceramic) and microchannel plates (MCPs) of third-generation low-light-level image intensifiers were measured with the static pressure-rising method and residual gas analysis by a quadrupole mass spectrometer. The experimental results show that the outgassing rate of the 95 alumina ceramic at 150 °C is about one order of magnitude higher than that at 23 °C, while the outgassing rate of the MCPs at 150 °C is only about half an order of magnitude higher than that at 23 °C, which is caused by a large number of microchannels in the MCPs. During the static accumulation of gas releasing, the outgassing rate of the 95 alumina ceramic first increases and then tend to stabilize at 23 °C, and it remains basically unchanged at 150 °C, while for the MCPs both the outgassing rates at these two temperatures increase gradually, and the outgassing rate at the higher temperature increased relatively slowly. The main gas components released from the 95 alumina ceramic and MCPs at 23 °C include H2O, H2, N2/CO and CO2. After the vacuum baking at 150 °C, the releasing ratio of H2O gas from the 95 alumina ceramic decreased greatly, and that of H2 gas increased dramatically, while the releasing ratio of H2O gas from the MCPs decreased just slightly, which indicates that the vacuum baking degassing for the MCPs is relatively difficult.

Outgassing Rates and Compositions of the Released Gases from Optical Fiber Panel and Photocathode Glass Used for Low-light-level Image Intensifiers

To analyze the vacuum failure mechanism of low-light-level image intensifiers in depth, the outgassing rates and compositions of the released gases from optical fiber panel and photocathode glass used for the image intensifiers were investigated by static pressure-rising method and residual gas analysis. The investigation results show that the outgassing rate of the optical fiber panel at a baking temperature of 150°C is only about one order of magnitude higher than that at 23°C, while the outgassing rate of the photocathode glass at 150°C is about two orders of magnitude higher than that at 23°C. As the static accumulation time of gas releasing extends, the outgassing rate of the optical fiber panel linearly increases at 23°C, and it remains basically unchanged at 150°C, while for the photocathode glass, its outgassing rate increases rapidly firstly and then tends to be stable gradually both at 23°C and 150°C. The gas compositions released from the optical fiber panel and photocathode glass at 23°C mainly include H2O, H2, N2/CO and CO2. After experiencing the vacuum baking at 150°C, the releasing ratio of H2O gas from the optical fiber panel decreased just slightly, which indicates that the vacuum baking degassing for the photocathode glass is relatively difficult; by contrast, the releasing ratio of H2O gas from the photocathode glass significantly decreased, and that of H2 gas obviously increased. These results can provide experimental bases for further optimizing the component materials and fabrication process of low-light-level image intensifiers.

Investigating the properties of nickel oxide thin films prepared via DC reactive magnetron sputtering for potential application in gas sensing

Nanocrystalline nickel oxide (NiO) thin films were developed on Si substrate using DC reactive magnetron sputtering. The goal of our study was to investigate the impact of O2/Ar gas ratios (varied from 10% to 20%) on the properties of sputtered NiO thin films. Further, after the deposition, all the samples were annealed at 400 ℃ in air. The prepared thin films were characterized by GIXRD, UV–visible spectroscopy, and FESEM to investigate the structural, optical, and morphological properties, respectively. The GIXRD results demonstrated the formation of the polycrystalline nature of sputtered NiO films with the FCC phase. As the O2 ratio was increased, the preferred orientation of NiO thin film was found to change from (111) to (200) plane with an average crystallite size of ∼ 14 nm. The UV–visible spectroscopy measurements show the semi-transparent nature of the deposited NiO films with a decreasing trend in the transmittance value from ∼ 83% to ∼ 77% with an increase in the O2 to Ar gas ratio. This behavior could be due to the poor crystallization of the film. However, the change in the calculated band gap of NiO films with respect to O2 partial pressure was found to be negligible and lay between 3.82 eV and 3.84 eV. The surface morphology was studied using FESEM, which depicted the uniform and homogenous distribution of grains with cracks on the film that improve the gas permeability; hence it may prove beneficial for gas sensing applications. Besides, the observed contact angle, as measured by the wettability test for the NiO films at different oxygen partial pressure, was greater than 90°, which shows that all the deposited NiO thin films are hydrophobic. Additionally, we have tested the CO gas sensor responses of the NiO sample deposited at a 15% O2/Ar ratio due to the high hydrophobic nature among all three ratios.

Effects of hydrogen fraction in co-injection gas on combustion characteristics of the raceway in low carbon emission blast furnace

Co-injection of coal and hydrogen-rich gas with oxygen blast at tuyere is a promising technology for low carbon emission blast furnace ironmaking, which favors the development of hydrogen-based reduction and affordable carbon capture. Effects of hydrogen fraction in the co-injection gas on the combustion characteristics in raceway are numerically studied. Results show that increase of hydrogen fraction in the co-injection gas accelerates the preferential combustion of the injected gas, which promotes the preheating and pyrolysis of pulverized coal. This compensates the oxygen-grabbing effect and improves the burnout of coal from 83.2% to 86.8% with the hydrogen fraction in co-injection gas increase from 20 vol% to 80 vol%. With the CO/H2 molar ratios in the co-injection gas of 8:2, 6:4, 4:6 and 2:8, the outlet CO/H2 molar ratios are 54:46, 42:52, 32:68 and 24:76 respectively. Combustion, gasification and water-gas shift reactions play conjoint roles in the redistribution of reducing gas species.

High-temperature electrochemical hydrogen separation from reformate gases using PBI/MOF composite membrane

In this paper, the high-temperature electrochemical Hydrogen (H2) purification performance of a polybenzimidazole/UIO-66 metal-organic framework (PBI/UIO-66) membrane is investigated and analyzed at different values of current, temperature, and reformate feed composition. Purification measurements show that a significant reduction in gas impurities can be obtained. In the performance tests, three different ratios of reformate gas (RG) (H2:carbon dioxide (CO2):carbon monoxide (CO)) as RG-1= (75:25:0), RG-2= (75:22:3), and RG-3= (95:0:5) were used. The highest purification values were observed at 160 °C as 99.999%, 99.931%, and 99.708% for RG-1, RG-2, and RG-3, respectively. The obtained results show that an electrochemical H2 purification (ECHP) based on PBI/UIO-66 composite membrane is promising for H2 purification.

Optimization of wellbore multiphase pipe flow calculation model for low permeability sandstone gas reservoir in Ordos Basin

The study of wellbore vertical pipe flow is the basis of reasonable production allocation and wellbore size optimization. According to the characteristics of low water gas ratio in sandstone gas reservoir of a gas field in Ordos Basin, the bottom hole pressure of typical gas wells in this area is calculated by using various wellbore pipe flow models such as Hagedorn brown, beggs Brill, Mukherjee Brill, gray and Aziz; Based on the measured bottom hole pressure, the relative performance coefficient evaluation method is used to optimize the wellbore calculation method. The results show that for the sandstone gas reservoir with low water gas ratio in gas field a, the calculation results of Hagedorn Brown model are in good agreement with the test results, so it is appropriate to use the Hagedorn Brown model to calculate the vertical pipe flow characteristics.

Gas-Liquid Flow Pattern and Hydrate Risk in Wellbore during the Deep-Water Gas-Well Cleanup Process.

The wellbore fluid flow characteristics and hydrate flow assurance problems during the deep-water gas well cleanup process seriously affect the safety of gas well testing. Aiming at the process of deep-water gas well cleanup where the liquid gas ratio changes dramatically, this study reveals the distribution law of gas-liquid flow patterns in the wellbore. Combined with the clean test conditions of deep-water gas wells, the transient numerical simulation and analysis are carried out. At the same time, a hydrate risk prediction model suitable for the well cleanup process is established to predict the hydrate risk under different cleaning conditions. The research results are as follows: (1) after flowback, the temperature at the wellhead and mud line presents different characteristics of temperature change, the wellhead temperature decreases first and then increases, while the flow temperature at the mud line rises first and then decreases; (2) slug flow and annular flow are more likely to occur in the wellbore under low wellhead pressure. Bubble flow often appears in the initial stage of flowback under high wellhead pressure and gradually changes into slug and annular flow patterns in the middle and late stages; (3) at the same flowback time, the wellbore will also present different flow patterns along the way. The lower part of the well bore mainly presents bubble flow and slug flow, and the upper and middle parts of the well bore mainly present annular flow patterns; (4) high liquid-gas ratio conditions, proper well cleaning speed, and the use of hydrate inhibitors can effectively reduce the hydrate risk during the cleaning process of deep-water gas wells.

Carbon isotope fractionation during shale gas release: Experimental results and molecular modeling of mechanisms

Carbon isotope fractionation during the release of gas from shales is a potential tool to evaluate the remaining gas content. However, the mechanism of carbon isotope fractionation during this process is still unclear. In this study, the δ13CH4 ratios of gases desorbed from two shale samples over a period of 800 min were analyzed. The results show that during gas release, the δ13CH4 values change in four stages: firstly decreasing from −27‰ to −31‰; then increasing significantly from −31‰ to −23‰. Subsequently, they decrease, and then finally increase slightly. Molecular simulations were also employed to calculate the adsorption and transport of 12CH4 and 13CH4. Based on simulation results, the adsorption amount, adsorption energy and density of 13CH4 are very similar to those of 12CH4. However, the molecular simulation showed significant differences in the transport of 13CH4 and 12CH4. By integrating the experimental and simulation results, a molecular mechanism for carbon isotope fraction is proposed. In Stage 1, gas expelled from the shale is mainly stored in fractures and macropores, and without the interaction of the gas with pore walls, 13CH4 is transported more slowly than 12CH4. In Stage 2, the high-pressure gas initially stored in micropores is expelled from the shale. The 13CH4 is transported more quickly in the small nanopores than 12CH4 when pressure is > 1 MPa, and the δ13C values increase correspondingly. In Stage 3, the gas pressure in the whole pore system is relatively low, and 13CH4 is transported more slowly than 12CH4 when migrating through small micropores. As a result, δ13C values show a slight decrease. In the last stage, since relatively more 13CH4 molecules remain in shale, the δ13CH4 values increase slightly again.

Improvements in thermal efficiency and exhaust emissions with ozone addition in a natural gas-diesel dual fuel engine

Here, ozone (O3) was introduced into the intake air in a natural gas fueled engine ignited by diesel fuel, a natural gas–diesel dual fuel engine, to utilize the reactive O-radicals decomposed from the O3 for the promotion of the ignition and for improvements in the thermal efficiency and exhaust emissions. The engine experiments were performed over a range of equivalence ratios of the natural gas in a single cylinder engine. The timing of the pilot injection of the diesel fuel was varied from early in the compression stroke to near top dead center to examine the changes in the effects of the O3 addition on the ignition and combustion with the pilot injection timing while varying the O3 concentration. The results showed that the combination of the O3 addition and the early pilot injection is a means to improve the thermal efficiency and unburned emissions with a small amount of O3. Further, the improvement in the thermal efficiency and the reduction of the unburned hydrocarbons with the O3 addition are more pronounced for lower equivalence ratios of natural gas, while the O3 addition has a limited effect on the thermal efficiency and the unburned hydrocarbons for higher equivalence ratios of the natural gas.

Screening of Absorbents for Viscose Fiber CS2 Waste Air and Absorption–Desorption Process

Screening of absorbents is essential for improving the removal rate of carbon disulfide (CS2) waste air by absorption. In this work, the UNIFAC model in Aspen Plus was utilized to calculate the excess Gibbs function and absorption potential of the binary system of CS2 with various alcohols, ethers, esters, amines, and aromatic hydrocarbons. The results were used to quantitatively compare the efficiency of each solvent for CS2 absorption. The theoretical predictions were then verified by absorption experiments in a packed tower. The results showed that the performance of various solvents to CS2 roughly followed the order of esters < alcohols < amines < heavy aromatics < glycol ethers. Meanwhile, N-methyl-2-pyrrolidone (NMP) is the optimal absorbent for CS2 waste air treatment. Additionally, the process parameters of absorption and desorption of NMP were optimized. The results illustrated that the average mass removal efficiency of CS2 by NMP is 95.2% under following conditions: liquid–gas ratio of 3.75 L·m−3, a temperature of 20 °C, and inlet concentration lower than 10,000 mg·m−3. Under the conditions of 115 °C, 10 kPa, and a desorption time of 45 min, the average desorption rate of CS2 is 99.6%, and the average water content after desorption is 0.39%. Furthermore, the recycled lean liquid can maintain an excellent CS2 purification effect during the recycling process.

Thermodynamic analysis of biomass and liquefied natural gas complementary CCHP system with liquid air energy storage

Biomass gasification, as a green energy, can be integrated with natural gas combined cooling, heating and power system to realize energy cascade utilization and reduce carbon emissions. This paper proposes a biomass gasification and liquefied natural gas complementary system, including biomass gasifier, gas turbine combined cycle, liquid air energy storage, and absorption chiller, to use more biomass efficiently. The system uses a liquid air energy storage system to absorb excess exhaust from the compressor and solves the compressor's surge when using low calorific value gas. This integration can raise mixed burning ratio of gas to 0.9 without modifying GT. The thermodynamic model of the system is established, and the evaluation indicators are proposed. Based on the rated power of a 270 MW gas turbine, the thermodynamic performances of the system under design conditions are simulated by Aspen Plus. The exergy flow diagrams of the three seasons are obtained. When the ambient temperature changes, the exergy destruction of gas turbine changes the most, and its exergy destruction in winter is 8.3% of the rated power lower than in summer. Besides, the heating exergy destruction of syngas reaches 76.8% for preheating feed water. The performances of the system under off-design conditions are discussed. When the mixed burning ratio of syngas and natural gas increases to 0.9, the input power of liquid air energy storage is 92 MW, and the output power is 53 MW. The electric efficiency of the system with liquid air energy storage increases by 5.6% compared to the system without liquid air energy storage. By selecting the design pressure of liquid air energy storage, the exergy efficiency can be increased by 6.5% when the mixed burning ratio is 0.9.

Integration of Metabolome and Transcriptome Profiling Reveals the Effect of Modified Atmosphere Packaging (MAP) on the Browning of Fresh-Cut Lanzhou Lily (Lilium davidii var. unicolor) Bulbs during Storage.

The fresh-cut bulbs of the Lanzhou lily (Lilium davidii var. unicolor) experience browning problems during storage. To solve the problem of browning in the preservation of Lanzhou lily bulbs, we first investigated the optimal storage temperature and gas ratio of modified atmosphere packaging (MAP) of Lanzhou lily bulbs. Then, we tested the browning index (BD), activity of phenylalanine ammonia lyase (PAL), polyphenol oxidase (PPO) and peroxidase (POD), the content of malonaldehyde (MDA) and other physiological activity indicators related to browning. The results showed that the storage conditions of 10% O2 + 5% CO2 + 85% N2 and 4 °C were the best. To further explore the anti-browning mechanism of MAP in fresh-cut Lanzhou lily bulbs, the integration of metabolome and transcriptome analyses showed that MAP mainly retarded the unsaturated fatty acid/saturated fatty acid ratio in the cell membrane, inhibited the lipid peroxidation of the membrane and thus maintained the integrity of the cell membrane of Lanzhou lily bulbs. In addition, MAP inhibited the oxidation of phenolic substances and provided an anti-tanning effect. This study provided a preservation scheme to solve the problem of the browning of freshly cut Lanzhou lily bulbs, and discussed the mechanism of MAP in preventing browning during the storage of the bulbs.

The Effect of Past Saturation Changes on Noble Gas Reconstructions of Mean Ocean Temperature

AbstractThe ocean's immense ability to store and release heat on centennial to millennial time scales modulates the impacts of climate perturbations. To gain a better understanding of past variations in mean ocean temperature (MOT), a noble gas‐based proxy measured from ancient air in ice cores has been developed. Here we assess non‐temperature effects that may influence the atmospheric noble gas ratios reconstructed from polar ice and how they impact the temperature signal with an intermediate complexity Earth system model. We find that changes in wind speed, sea‐ice extent, and ocean circulation have partially compensating effects on mean‐ocean noble gas saturation, leading to a slight reduction of noble gas undersaturation at the Last Glacial Maximum (LGM). Taking these effects and ice core measurements into account, our model suggests a revised MOT difference between the LGM and pre‐industrial of −2.1 ± 0.7°C that is also in improved agreement with other independent temperature reconstructions.

Dichlorodifluoromethane-carbon dioxide: A dielectric mixture as a sustainable alternative to SF6 in high voltage applications

Sulphur hexafluoride (SF6) gas is the frequently consumed gas in High Voltage (HV) applications due to its high dielectric permittivity and arc-quenching property. However, due to its long Atmospheric Lifetime (AL), high Global Warming Potential (GWP), and other environmental concerns there is a need for a new sustainable gas as an alternative to SF6. Therefore, in this research, we present dichlorodifluoromethane (R-12) in conjunction with carbon dioxide (CO2) as an alternative. Compared to SF6, R-12 has 3,100 years shorter atmospheric lifetime and 15,400 less GWP. Moreover, CO2 is mixed with R-12 as a gas carrier to achieve a low boiling point as that of SF6. High Voltage Direct Current (HVDC), High Voltage Alternating Current (HVAC), and self-recoverability tests were conducted under varying concentrations of gas ratios at different pressures and a standard constant temperature. Comparison analysis showed that R-12 dielectric strength is close to that of SF6, and its mixture with CO2 possessed increased dielectric strength compared to a nitrogen and air mixture beyond 206.84 kPa. For HVAC and HVDC, a mixture of 50% R-12% and 50% CO2 establishes an unimpeachable ratio for HV applications. The mixture has self-recoverability properties and possesses positive synergism, which leads to the conclusion that the mixture of R-12 with CO2 enhances the dielectric strength compared to pure gases, as well as reduces costs.

Deep reinforcement learning based controller with dynamic feature extraction for an industrial claus process

BackgroundThe significant time delay between the manipulated and controlled variables introduces challenges in the task of system identification when implementing model predictive control (MPC) for an industrial process. Recently, deep reinforcement learning (DRL) with model-free characteristics has attracted considerable attention from the process control community. However, the model-free assumption in DRL is based on the property of the Markov decision process (MDP), in which all state variables must be observed. This assumption is not true for an industrial process. MethodsIn this study, the sequence-to-sequence (Seq2seq) network was employed to build a surrogate model based on the industrial Claus process data. Meanwhile, the hidden state output from the encoder of the Seq2seq network, which represents the dynamic feature of the process, connects to the DRL-based controller to compensate for the partial observabilities of a real process. Significant findingsThe results show that the standard deviation of the control variable, which refers to the H2S to SO2 concentration ratio in the tail gas, can be reduced by up to 55% using the proposed DRL-based controller comparing with the current control strategy.

Adsorption Equilibrium and Diffusion of CH4, CO2, and N2 in Coal-Based Activated Carbon.

Coal-based activated carbon is an ideal adsorbent for concentrating CH4 from coalbed methane and recovering CO2 from industrial waste gas. In order to upgrade the environmentally protective preparation technology of coal-based activated carbons and clarify the adsorption equilibrium and diffusion rules of CH4, CO2, and N2 in these materials, we prepared granular activated carbon (GAC) via air oxidation, carbonization, and physical activation using anthracite as the raw material. Also, we measured the adsorption isotherms and adsorption kinetic data of GAC by the gravimetric method and characterized its surface chemical properties. According to the results, GAC had abundant micropore structures with a pore size mainly in the range of 5.0-10.0 Å, and its surface was covered with plentiful oxygen-containing functional groups. The specific pore structure and surface chemical properties could effectively improve the separation and purification effects of GAC on CH4 and CO2. In the temperature range of 278-318 K, the equilibrium separation of CH4/N2 by GAC with a coefficient between 3 and 4 could be achieved. Also, the CO2/CH4 separation coefficient decreased with the increase in temperature but remained around 3. The bivariate Langmuir equation could describe the adsorption behaviors of GAC on CH4/N2, CO2/N2, and CH4/CO2. With the increase in the concentrations of CH4 and CO2 in the gas phase, the difference between the adsorption capacity of CH4 or CO2 and that of N2 became greater. The change of the gas ratio did not affect the characteristics of preferential adsorption of CH4 and CO2. At different temperatures (278, 298, and 318 K), the diffusion coefficients of CH4, N2, and CO2 at various pressure points showed predominately a small variation without an obvious trend. These results demonstrated that the separation of CH4/N2, CO2/N2, and CH4/CO2 by the activated carbon could only rely on the equilibrium separation effect rather than the kinetic effect.

Conductive TiN thin films grown by plasma-enhanced atomic layer deposition: Effects of N-sources and thermal treatments

This work consists of optimizing TiN plasma-enhanced atomic layer deposition using two different N-sources: NH 3 and N 2. In addition to maximizing the growth per cycle (GPC) and to shorten the deposition duration, comprehensive in situ and ex situ physicochemical characterizations give valuable information about the influence of the N-source nature, their dilution in Ar, and the plasma power on layer’s final properties. N 2 and NH 3 dilutions within Ar are extensively investigated since they are critical to decreasing the mean free path ( ℓ) of plasma-activated species. A 1:1 gas ratio for the N-sources:Ar mixture associated with low flows (20 sccm) is optimal values for achieving highest GPCs (0.8 Å/cycle). Due to lower reactivity and shorter ℓ of the excited species, N 2 plasma is more sensitive to power and generator-to-sample distance, and this contributes to lower conformality than with NH 3 plasma. The resistivity of the initial amorphous films was high ( ≥ 1000 μ Ω cm) and was significantly reduced after thermal treatment ( ≤ 400 μ Ω cm). This demonstrates clearly the beneficial effect of the crystallinity of the film conductivity. Though N 2 process appears slightly slower than the NH 3 one, it leads to an acceptable film quality. It should be considered since it is nonharmful, and the process could be further improved by using a reactor exhibiting optimized geometry.

The deep origin of ground fissures in the Kenya Rift Valley

Intense volcanic and geothermal activities characterize the Great Rift Valley of East Africa. Ground fissure disasters of the Great Rift Valley have garnered increasing attention in recent years. Through field investigations, trenching, geophysical exploration, gas sampling and analysis, we determined the distribution and origin of 22 ground fissures within the Kedong Basin of the Central Kenya Rift. These ground fissures caused varying degrees of damage to roads, culverts, railways, and communities. Trenching and geophysical exploration have shown that ground fissures in sediments are connected to rock fractures with gas escaping. The gases expelled from the rock fractures contained methane and SO2, which were absent in the normal atmosphere, and 3He/4He ratios in gases measured further indicated that the volatiles were derived from the mantle, suggesting that these rock fractures extended deep into the underlying bedrock. Spatial correlations with rock fractures demonstrate the deep origin of these ground fissures, which are associated with active rifting, plate separation, and volcanism. The ground fissures are formed due to movement on the deeper rock fractures, and then the gas escapes through the fissures. Determining the unusual origin of these ground fissures can not only guide infrastructure development and urban planning but also contribute to the safety of local communities.

Effective flue gas desulfurization and denitrification using a one-step combined ozone and UV technique

The combination of Ozone and UV irradiation has been studied for the removal of SO2 and NOX in the aqueous mode. It has been attempted to get complete removal of the flue gases by different combinations of molar ratio of Ozone, flue gas, and UV irradiation power. The amount of hydroxyl radicals generated by the combination of UV and O3 has been measured. A complete comparison of the contribution of the oxidants such as ozone, UV and hydroxyl radicals has been depicted. Due to the high power demand for UV lamps and ozone generators, it is important to find a suitable route to decrease power consumption. This has been achieved by changing the operation mode of the gases, where more than 95% NOX and almost 100% SO2 removal were recorded at a low ozone generation rate and a moderate UV lamp.

Study on double differential pressure measurement method of gas-liquid two-phase flow in high gas content wells

The production of natural-gas wells contains natural gas and a small amount of liquid, which is a wet gas composed of oil, gas and water. For dynamically monitor the liquid and gas production from a single well, there is an urgent need for a low-cost, small-volume online metering device for wet gas flows through a single well. Aiming at the problem, this paper designs a wet gas flow measurement device for a long-throated Venturi tube based on the double differential pressure method. By combining experiments and numerical simulations, a matching flow calculation model was developed. Based on the experimental data of NEL's 6-inch standard Venturi tube wet gas over-reading, the numerical simulation method is used to carry out the research of high-pressure wet gas measurement under the pressure condition of 2, 4 and 6 MPa. The simulation results of two multiphase flow models, DPM and Euler, are compared with the experimental values of NEL. The results show that the maximum relative error is less than 10%, and the Euler model is more suitable for the numerical simulation of high-pressure wet gas. According to the actual production from the gas well, a long-throated Venturi tube with a throttling ratio of 0.5 and a diameter of DN50 was designed, and a numerical simulation study of wet gas under a pressure of 2, 3 and 4 MPa was carried out. Numerical simulation results show that the change laws of over-reading and liquid-gas mass ratios of high-pressure wet gas are consistent with those of low-pressure wet gas. The numerical simulation results are used to correct the flow calculation model of low-pressure wet gas, and a flow calculation model suitable for high-pressure wet gas in gas wells is obtained. The gas flow prediction accuracy of the flow calculation model was lower than ±3%, and the liquid flow prediction value was lower than ±10%. Compared with other measurement methods without separation of wet gas, the long-throated Venturi tube based on the double differential pressure method has a simple structure and low measurement cost. By further optimizing and expanding the measurement model, after improving the accuracy, it can be installed in the wellhead pipeline to monitor the oil and gas production from a single well in real time. This can provide support for gas reservoir exploitation decisions.