Article
Chemistry, Analytical
Shifeng Yu, Yongjia Wu, Shuyu Wang, Michael Siedler, Peter M. Ihnat, Dana Filoti, Ming Lu, Lei Zuo
Summary: This paper presents a novel MEMS-based differential scanning calorimeter (DSC) for direct thermal characterization of protein samples. The DSC exhibited high sensitivity, low noise, high scanning rate, and low sample consumption volume. The study demonstrated that the MEMS DSC is an effective tool for directly understanding the thermal stability of antibodies in a high-throughput and low-cost manner compared to conventional calorimeters.
Article
Energy & Fuels
Xue Zou, Mucong Zi, Tiantian Wu, Yuanxin Yao, Caifeng Yang, Daoyi Chen
Summary: In this study, four new kinetic hydrate inhibitors (KHIs) were successfully synthesized by introducing 1-vinylimidazole (VI) or vinylacetate (VAc) monomer using radical polymerization method. These newly-synthesized copolymer KHIs exhibited high cloud points and biodegradability, and showed remarkable inhibition performance on hydrate nucleation and growth. A novel inhibition mechanism hypothesis was proposed to explain the inhibitory effect of these new KHIs under high subcooling conditions.
Article
Energy & Fuels
Caifeng Yang, Mucong Zi, Guozhong Wu, Xue Zou, Kai Liu, Daoyi Chen
Summary: This study evaluated the influence of kinetic hydrate inhibitor (KHI) on methane - propane hydrate formation kinetics under different subcooling and concentration conditions. It proposed a "concentration effect" concept that highlighted the nonmonotonic relationship between KHI performance and concentration. Two hypotheses were proposed to explain this phenomenon, and the results showed that the concentration effect became less obvious under certain experimental conditions.
Article
Engineering, Chemical
Qian Zhang, Malcolm A. Kelland
Summary: Kinetic hydrate inhibitors (KHIs) have been used for over 25 years in oil and gas production flowlines to prevent gas hydrate formation. The main component in KHI formulations is a water-soluble polymer, with polymaleamides showing significant performance enhancement in inhibiting gas hydrate formation. Studies have improved our understanding of the optimal structural features for KHI polymers.
CHEMICAL ENGINEERING SCIENCE
(2021)
Article
Polymer Science
Jianlong Wang, Jinsheng Sun, Hang Bian, Qibing Wang, Zhenbo Feng, Cheng Lu, Han Ren, Rongchao Cheng, Jintang Wang, Ren Wang
Summary: Natural gels have attracted global research attention for their greenness, environmental-friendliness, and good hydrate inhibition performance. This study evaluated the inhibition performance of xanthan gum and pectin on hydrate nucleation and growth in sediment environments and revealed the internal inhibition mechanisms. The study also investigated the effects of natural gels on sediment dispersion stability and low-temperature fluid rheology.
Article
Energy & Fuels
Ankur Singh, Ajay Suri
Summary: Hydrate formation experiments were conducted to evaluate the synergy between three natural proteins and four standard reference kinetic hydrate inhibitors. The results showed that casein peptone had the best synergy with PVCap, whey protein had the best synergy with HIOP-1800, and bovine serum albumin consistently showed synergy with the standard KHIs.
Article
Energy & Fuels
Ahmad A. A. Majid, Jefferson Creek, Sivakumar Subramanian, Douglas A. Estanga, Carolyn A. Koh
Summary: The study introduces an HPA technique for evaluating hydrate plugging tendency in crude oil systems, using HP-DSC tests to analyze the impact of different factors on hydrate formation. Results indicate that an increase in water content exacerbates the risk of blockages, while an increase in salinity reduces plugging tendency.
Article
Engineering, Chemical
Jinxiang Liu, Wenxiu Zhang, HuanHua Wu, Zhigang Gao, Yiwei Feng, Shengli Liu
Summary: In this study, the adsorption of kinetic hydrate inhibitors (KHIs) on metal surfaces was investigated using first-principles computational method. It was found that KHIs preferentially adsorb onto the Fe surface and undergo electron transfer with the Fe surface, while acting as electron donors to the Fe3O4 surface. Hydrophobic interaction plays a dominant role in adsorption affinity, and electron transfer enhances adsorption stability. Additionally, the adsorption affinity of four poly(N-vinyl lactam)s with different ring sizes was compared, with PVCap exhibiting the strongest adsorption strength on Fe surface.
CHEMICAL ENGINEERING SCIENCE
(2023)
Article
Thermodynamics
Zhi Li, Yue Zhang, Yimao Shen, Liwei Cheng, Bei Liu, Kele Yan, Guangjin Chen, Tianduo Li
Summary: The synergistic mechanism of KHIs and THIs in preventing methane hydrate formation involves three stages, with gas adsorption playing a dominant role. The addition of THIs to solutions containing KHIs enhances methane attraction and weakens the driving force for hydrate formation. It is suggested that the methane adsorption capacity of hybrid inhibitors should be considered in future development.
Article
Energy & Fuels
Hanie Mohsenzade, Shima Foroutan, Ali Dashti, Navid Ramezanian, Hadi Roosta
Summary: In this study, poly(N-vinylcaprolactam)s were synthesized as potent kinetic hydrate inhibitors, with modifications such as 3-mercaptopropionic acid and mercaptoacetic acid showing superior performance in reducing the growth rate of structure I and structure II hydrates. The synthesized polymers also outperformed commercial products in delaying induction time and increasing relative inhibition power values.
Article
Engineering, Environmental
Mucong Zi, Guozhong Wu, Jiang Wang, Daoyi Chen
Summary: This study systematically investigated the influence of light oil components and asphaltene on gas hydrate formation through experiments, as well as evaluated the performance of commercial kinetic hydrate inhibitors (KHIs) in different oil-water systems. The results showed that light oil can promote initial hydrate growth, while asphaltene, especially with light oil solvent, has an inhibition effect on gas hydrate formation.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Energy & Fuels
Jianlong Wang, Jinsheng Sun, Ren Wang, Kaihe Lv, Jintang Wang, Bo Liao, Xiaomei Shi, Qibing Wang, Yuanzhi Qu, Hongjun Huang
Summary: This research investigates the effects of hydrophilic amino acids on hydrate formation and the synergistic inhibition effects with kinetic inhibitors. It reveals that L-arginine and glycine can disturb water molecules and reduce their activity, resulting in both kinetic and thermodynamic inhibition effects. Combinations of L-arginine and glycine with kinetic inhibitors show synergistic inhibition effects on hydrate formation, with certain combinations exhibiting better performance.
Article
Chemistry, Multidisciplinary
Abdelatif Laroui, Malcolm A. Kelland, Dong Wang, Siyuan Xu, Ying Xu, Ping Lu, Jian Dong
Summary: This study investigates a novel group of copolymers with N-vinylcaprolactam and N-acryloylpyrrolidine structural units and analyzes the relationships between their amphiphilicity, nonfreezable bound water, and kinetic hydrate inhibition. The research reveals that the appropriate amphiphilicity of the copolymers can delay hydrate crystal growth and achieve optimal interfacial properties.
Article
Energy & Fuels
Ankur Singh, Ajay Suri
Summary: This study investigates the synergistic effects of three plant-based polysaccharides with four kinetic hydrate inhibitors (KHIs), and experimental results show that the polysaccharides can effectively enhance the hydrate inhibition performance.
Article
Energy & Fuels
Morteza Aminnaji, Ross Anderson, Khosro Jarrahian, Bahman Tohidi
Summary: Low dosage kinetic hydrate inhibitors (KHIs) are an effective method for preventing solid gas hydrate plug formation in the oil and gas industry. Efforts have been made to develop environmentally friendly KHIs due to concerns around the non-biodegradability of traditional chemistries. Natural pectin has been identified as a potential green KHI with good hydrate inhibition properties. This study compared the performance of food grade apple pectin and the commercial biodegradable KHI polymer Luvicap Bio using crystal growth inhibition methods. Results show that Luvicap Bio offers significant inhibition to high subcoolings, while pectin only shows some anti-nucleation properties.
Article
Engineering, Environmental
Jyoti Shanker Pandey, Qian Ouyang, Nicolas von Solms
Summary: Recent limited studies have shown that multistep slow depressurization of mixed CH4/CO2 hydrates can enhance CH4 recovery and increase CO2 storage after injection. The resistivity variation, gas recovery and storage were investigated to study hydrate saturation and production/storage yield changes. Results indicate the presence of two stability zones during mixed hydrate dissociation, providing opportunities for additional CH4 recovery and CO2 storage.
CHEMICAL ENGINEERING JOURNAL
(2022)
Review
Energy & Fuels
Jyoti Shanker Pandey, Nicolas von Solms
Summary: Recent research and review papers have emphasized the positive synergies between gas hydrates and metal-organic frameworks (MOFs) when it comes to gas separation and storage. MOFs are programmable modular structures consisting of metal nodes and organic linkers that offer large pore volume and surface area for capturing, separating, and storing gases. The usage of MOFs in water-based technologies is an exciting research topic due to its interactions with water in nanopores and surface. This review examines the current state of the art, presents critical technical aspects, and discusses potential research areas and unanswered questions.
Article
Thermodynamics
Qian Ouyang, Jyoti Shanker Pandey, Nicolas von Solms
Summary: This study investigated the dissociation characteristics of CH4/CO2 hydrates in unconsolidated sediments using slow multistep depressurization. The results showed that CO2 was preferably encaged in hydrate than CH4, especially in unconsolidated sediments. CH4-rich hydrates in unconsolidated sediments could be effectively exploited through multistep depressurization, with higher CH4 recovery at lower depletion pressure.
Article
Thermodynamics
Gcinisizwe Msimisi Dlamini, Philip Loldrup Fosbol, Nicolas von Solms
Summary: This study examines the phase equilibria of sulphur compounds in mixtures relevant to carbon capture and storage. The cubic plus association equation of state is used as the modelling tool. Different approaches are considered, and the allocation of association sites for the sulphur compounds is found to improve the modelling of phase equilibria behavior.
FLUID PHASE EQUILIBRIA
(2023)
Article
Thermodynamics
Martin Due Olsen, Georgios M. Kontogeorgis, Xiaodong Liang, Nicolas von Solms
Summary: This study compares five different models of relative static permittivity in the electrolyte Cubic Plus Association (e-CPA) equation of state. The model based on ion association performs the best in describing the experimental data. However, it has limitations in predicting individual ion activity coefficients.
FLUID PHASE EQUILIBRIA
(2023)
Article
Thermodynamics
Daniel Qvistgaard, Julia Trancoso, Even Solbraa, Marie Vikre Danielsen, Eleni Panteli, Georgios M. Kontogeorgis, Nicolas von Solms
Summary: This study investigated the phase equilibria of TEG/Water/Natural Gas systems and concluded that the 4C association scheme with the CPA EoS performed the best. The research provides valuable insights into the complex behavior of these systems and contributes to the understanding of multi-component vapor-liquid equilibrium in petroleum fluids.
FLUID PHASE EQUILIBRIA
(2023)
Article
Thermodynamics
Julia Trancoso, Daniel Qvistgaard, Marie V. Danielsen, Eleni Panteli, Even Solbraa, Georgios M. Kontogeorgis, Nicolas von Solms
Summary: This study measured vapor-liquid equilibrium data for the system triethylene glycol + water + methane under different conditions, expanding the experimental database for subsea gas processing technologies. A comparison with literature data revealed inconsistencies in one data set. The cubic-plus-association (CPA) equation-of-state modeling capability was reevaluated in this study.
JOURNAL OF CHEMICAL AND ENGINEERING DATA
(2022)
Article
Engineering, Environmental
Qian Ouyang, Jyoti Shanker Pandey, Nicolas von Solms
Summary: This study investigated the morphological formation and dissociation of methane hydrates, and found that hydrate nuclei formed uniformly in hydrophilic pores but unevenly in hydrophobic pores. The morphology of hydrates varied, with coarse films in gas-rich pores and partially smooth crystals in water-rich or moderate pores. In addition, gas/water diffusion and localized pressure variations played important roles in the formation and dissociation of hydrates.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Engineering, Chemical
Emil Madsen, Randi Neerup, Arne Gladis, Jens K. Jorsboe, Nicolas von Solms, Philip L. Fosbol
Summary: This study compares different pressure drop correlations for packed columns and finds that, surprisingly, complicated correlations do not provide better estimates than simple equations for a system of water and atmospheric air. The study investigates the predictiveness of four different correlations on pressure drop in packed columns using experimental data.
CHINESE JOURNAL OF CHEMICAL ENGINEERING
(2023)
Article
Thermodynamics
Daniel Qvistgaard, Georgios M. Kontogeorgis, Xiaodong Liang, Julia Trancoso, Even Solbraa, Nicolas von Solms
Summary: The formation of gas hydrates in water-saturated natural gas can cause damage to subsea pipelines, so efforts must be made to inhibit these processes. One commonly used method is gas dehydration using triethylene glycol (TEG). This study focuses on optimizing binary interaction parameters (BIP) for TEG-Ethane and TEG-Propane in different association schemes to improve the thermodynamic modeling of TEG/water/natural gas systems. The results showed a low degree of uncertainty for the TEG-Ethane parameter, while the TEG-Propane parameter had higher uncertainties due to the linear correlation between the terms in the BIP.
FLUID PHASE EQUILIBRIA
(2023)
Article
Thermodynamics
Martin Due Olsen, Georgios M. Kontogeorgis, Jean-Charles de Hemptinne, Xiaodong Liang, Nicolas von Solms
Summary: This study compares two successful Equations of State (EoS) models, namely the electrolyte Cubic Plus Association (e-CPA) EoS and the electrolyte Polar Perturbed Chain Statistical Associating Fluid Theory (e-PPC-SAFT) EoS. The models are compared by reparameterization of the models for the relative static permittivity. It is found that the permittivity models that only predict part of experimental decrease perform the best for the properties MIAC, osmotic coefficients and density.
FLUID PHASE EQUILIBRIA
(2023)
Article
Energy & Fuels
Johannes Liljenhjerte, Sindhu Vudayagiri, Nicolas von Solms, Jens Vinge Nygaard
Summary: This study investigates the feasibility of using strategically placed periodic supports to increase the buckling stability of coiled tubing (CT) operations. By modifying tubing force analysis (TFA) and finite element analysis (FEA) models, exact locations of supports are determined. Experiments demonstrate that sufficient periodic support maintains its stabilizing integrity beyond the point of helical buckling.
GEOENERGY SCIENCE AND ENGINEERING
(2023)
Article
Energy & Fuels
Qian Ouyang, Jyoti Shanker Pandey, Yao Xu, Nicolas von Solms
Summary: CH4-CO2 swapping is a promising technique for producing CH4 gas and storing CO2, but inefficient CO2 diffusion limits its large-scale application. To improve CO2 diffusion, multistep depressurization (MD) is performed on CH4/CO2 hydrates after swapping. This study combines non-destructive X-ray computed tomography (CT) with mixed hydrate kinetics to visualize hydrate morphology during MD and examine the effects of particle sizes and L-methionine on dissociation parameters. The results show that hydrate or gas phase enlargements occur during MD, with the most obvious changes observed for a particle size of 3 mm due to good pore connectivity and efficient mass transfer. L-methionine enhances CO2 storage but has no direct effect on CH4 production. This work provides valuable insights into hydrate exploitation and carbon emission mitigation.
GAS SCIENCE AND ENGINEERING
(2023)
Article
Engineering, Chemical
Aziz Alhejaili, Ponnivalavan Babu, Nagu Daraboina
Summary: Clathrate hydrate applications have increased significantly, and one promising application is produced water purification. However, limitations such as high temperature and slow kinetics have persisted. This study investigates the effect of prevalent salts on the equilibrium of TBAC hydrates and finds that lower TBAC concentrations have better tolerance to higher contaminant concentrations. Additionally, operating at lower TBAC concentrations in high salinity water provides optimal water recovery.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Article
Chemistry, Physical
Evangelos Drougkas, Michael Bache, Xiaodong Liang, Nicolas von Solms, Georgios M. Kontogeorgis
Summary: This work aims to evaluate the application of infrared spectroscopic methods in studying the structural properties of liquid alcohols and discusses the methodologies for extracting free hydroxyl groups/monomer fractions in 1-alcohol solutions. The results show a discrepancy in the data of saturated liquid methanol and ethanol, indicating a stronger association of methanol at higher temperatures compared to ethanol.
JOURNAL OF MOLECULAR LIQUIDS
(2023)