Journal of Water Process Engineering
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2023
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IF 7
Ce Wang,Yuling Lü,Chao Song,Jiakai Shi,Peng Zhang,Limin He
The poor adhesion of oil droplets and bubbles in the flotation process leads to inefficient separation of oil and water. In this paper, condensate bubbles were prepared by partial vaporization of low boiling point condensate to increase the oil removal effect. The purpose of partial vaporization was achieved by bringing emulsified condensate droplets into the produced water at different temperatures. The structure of the bubble is composed of condensate film wrapped around the gas core of the vaporized portion. The contact angle between condensate bubble and oil surface is >150°, which show great similarity-intermiscibility. The average bubble size prepared at 303 K - 318 K is 20 - 100 μm. The stability of bubbles decreased with an increase in temperature, the half-decay time decreased from 340 s to 110 s, and the zeta potential decreased from −31 mV to −12 mV. However, the gas hold-up of the bubbles first increased and then decreased with the increase in temperature, while the highest gas holdup was 21 % at 313 K. The rise of the condensate/water ratio (R con-wat ) did not increase the stability of the bubbles, but the gas holdup increase. The condensate bubble flotation experiment found that at the optimum temperature 313 K, the oil removal efficiency of 1.5 % R con-wat can reach 85 %. In contrast, the oil removal efficiency of the dissolved air flotation experiment is <75 %. Otherwise, with a smaller amount of flocculant (ferric chloride), the oil removal efficiency of condensate bubble flotation can reach >95 %.
研究领域:
石油工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2025
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IF 5.4
Junhuan Zong,Guosheng Ai,Dongyin Yan,Yaming Qi,Long Li,Yuanzhu Mi,Yu Ding,Chunyan Zhang,Xuemin Yan
Wax deposition is a common problem in the transportation of gas condensate and crude oil. Polymers are often used as flow improvers to prevent wax agglomeration. In this work, comb-shaped ternary copolymers poly (imidazole olefin-co-ɑ-olefin-octadecyl maleate) with polar groups and non-polar long chains were synthesized through esterification and free radical polymerization. The influences of the monomer molar ratio of imidazole olefin and the dosage of polymers on the flow properties of gas condensate were studied. The mechanism reveals that the copolymers interacted with wax crystals through adsorption and co-crystallization to modify the van der Waals forces and electrostatic forces between the wax crystal molecules, thereby achieving the purpose of inhibiting wax precipitation. Imidazole olefin, ɑ-olefin and octadecyl maleate with a molar ratio of 1:10:10 exhibits optimal flow performance on waxy gas condensate. The pour point and wax appearance temperature of the condensate oil containing 4% on-site wax after being treated with NCMO-2 was reduced by 22 ℃ and 11 ℃, respectively. This work provides a reference for the synthesis of flow improvers for waxy condensate oil.
研究领域:
石油工程
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高分子化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Omega
·
2019
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IF 2.584
Chaochao Qu,Ji Wang,Hongyao Yin,Guangliang Lu,Zuyou Li,Yujun Feng
Foams are widely used to remove liquid loading at the bottom of gas wells to improve natural gas production. However, it becomes ineffective when a gas well contains a large amount of hydrocarbon condensate because oil will rupture the foams. In this work, condensate oil-tolerant foams were developed and stabilized by a mixture of cocamidopropyl hydroxyl sulfobetaine (CHSB) and sodium dodecyl sulfate (SDS). The foam properties are examined at different temperatures under atmospheric conditions and high pressures with various contents of condensate oil. It is found that the foam stability is improved when the oil content is increased; in addition, high temperature, high salinity, and high pressure are beneficial for foam stabilizing. To reveal the mechanism of stable foam in the presence of high content of oil, a confocal microscope was employed to visualize oil–foam interactions. It was observed that the high stability of the SDS–CHSB foams is ascribed to the formation of stable pseudoemulsion between oil droplets and the gas–liquid interface. Such condensate oil-tolerant foams show promising potential to be used in the foam-assisted lift process during natural gas production.
研究领域:
石油工程
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界面化学
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能源技术
✓ 已验证
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
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2021
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IF 9.229
Yongfei Li,Yanling Wang,Qian Wang,Zhonghua Liu,Longhao Tang,Lei Liang,Chuanbao Zhang,Qiang Li,Ning Xu,Jinsheng Sun,Wenjing Shi
It is well-known that the production of gas-condensate reservoirs is significantly affected by the liquid condensation near the wellbore region. Gas-wetting alteration can be one of the most effective approaches to alleviate condensate accumulation and improve liquid distribution. However, gas well deliverability is still limited because the wettability of cores is altered only from liquid-wetting to intermediate gas-wetting by using traditional chemical stimulation. To solve this bottleneck problem, herein, we developed a fluorine-functionalized nanosilica to achieve super gas-wetting alteration, increasing the contact angles of water and n-hexadecane on the treated core surface from 23 and 0° to 157 and 145°, respectively. The surface free energy reduces rapidly from 67.97 to 0.23 mN/m. The super gas-wetting adsorption layer on the core surface formed by functionalized nanosilica not only increases the surface roughness but also reduces the surface free energy. The core flooding confirms that the required pressure for displacement is apparently reduced. Meanwhile, the core permeability can be dramatically restored after the super gas-wetting alteration. The microscopic visualization is employed to further understand the impact of fluorine-functionalized nanosilica on the fluid flow behavior and mechanism in porous media. The oil saturation in the micromodel decreases sharply from 48.75 to 7.84%, eliminating the “water locking effect” and “Jiamin effect”, which indicates that the added functional nanosilica effectively improves fluid flow capacity and may contribute to production in the gas condensate reservoirs. In addition, this work reveals the fluid flow behavior and mechanism in the reservoir in detail, which will expand the better application of this material to many oilfields and other mining engineering systems.
研究领域:
石油工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENERGY & FUELS
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2022
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IF 4.654
Bowen Sun,Ping Guo
Determination of condensate oil saturation in condensate gas reservoirs is the key parameter for estimating condensate oil blockage and gas well productivity. In PVT experiments, the constant volume depletion (CVD) method is usually adopted to obtain condensate oil saturation. However, in this method, the effect of porous media is not considered. This study applied a low field nuclear magnetic resonance (NMR) test instrument in which 1D T2 and 2D T1–T2 NMR techniques are carried out to investigate the condensate oil saturation of “condensate gas-saturated” core plugs in the depletion process of 29 to 5 MPa at 25 °C. It was observed here that the T1/T2 ratios of condensate oil and gas at the signal peak are approximately 20 and 60, respectively, and the condensate oil and gas could be distinguished by positions in 2D NMR T1–T2 maps. Additionally, a standard equation (the relationship between the signal intensity and the condensate oil saturation) with an excellent linear relationship was established for the calculation of the condensate oil saturation in core plugs. The results indicated that the condensate oil first appears in micropores, and the retrograde condensation phenomenon of the core mainly comes from the contribution of mesopores and macropores; furthermore, the maximum condensate oil saturation in the porous medium is 5.36% higher than that in the PVT cylinder, and the dew point pressure in the porous medium is 11.83% higher than that in the PVT cylinder. The T1–T2 NMR technique may become an efficient approach for assessing fluid distributions and saturations, simultaneously possessing potential applications for characterizing fluid occurrence states in the core.
研究领域:
石油工程
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地球物理
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储层表征
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2023
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IF 6
Sanbao Dong,Jiabao Fan,Chenwei Liu,Yongli Yan,Weiwei Han
Liquid buildup in gas wells would undoubtedly obstruct the gas production. The use of foaming surfactants to generate foams and remove the loaded liquid is very common. Due to the undesirable conditions (e.g., high condensate cut (ratio of condensate oil volume to total liquid volume) and high salinity, etc.) that often encountered in the wells, different foaming surfactants were often compounded together to unload liquid in gas wells. In this paper, lauramide propyl dimethylamine (C12 Amine), palmitamide propyl dimethylamine (C16 Amine) and cocamidopropyl betaine (CAPB) were synthesized and compounded with L-aspartic acid (Asp) and N-lauroylsarcosine sodium (LSS) to form foaming supramolecular complexes through optimization (with Waring blender method and liquid unloading tests) to quantify their application potentials in foam-based deliquification treatment for gas wells. The C12 Amine-Asp-LSS-CAPB complex (in an optimized mole ratio of 10:4:14:7) exhibited superior condensate tolerance than the C16 Amine-Asp-LSS-CAPB complex (in an optimized mole ratio of 10:4:14:42). The salinity posed a significant influence on the liquid unloading performance ( k ) and foaming efficiency ( ƞ , defined as the ratio of the foam mass to the initial liquid mass) of the C12 Amine-Asp-LSS-CAPB complex, however, the nitrilotriacetic acid trisodium (NTA) can greatly enhance the properties of the C12 Amine-Asp-LSS-CAPB complex against the salinity (up to 6 × 10 4 mg/L). The temperature (25 °C −90 °C) favored the performances (as indicated by k and ƞ ) of the C12 Amine-Asp-LSS-CAPB complex, which achieved k and ƞ values of 85.0% and 100% at 90 °C, respectively. Meanwhile, the synergy observed in the foaming ability, foam stability and liquid unloading performance tests using the C12 Amine-Asp-LSS-CAPB mixture was also proved by the surface tension analysis and the calculations of the supramolecular interactions (interaction energies and electrostatic interactions).
研究领域:
化学工程
·
石油工程
·
表面活性剂科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）