30 research outputs found
Separation of Carbon Dioxide and Methane via Hydrate Formation with Utilization of Modified Spray Reactor and Thermodynamic Promoters
No full textPemanasan global dan perubahan iklim telah menggalakkan negara-negara untuk mengurangkan
kepekatan karbon dioksida dalam atmosfera. Penangkapan C02 adalah satu langkah penting
untuk mengurangkan pelepasan gas rumah hijau
Recent Advances on Carbon Dioxide Capture through a Hydrate-Based Gas Separation Process
No full textHydrate Based Gas Separation (HBGS) process is gaining interest globally as a greener solution for separation of CO2 from gaseous streams. In this paper, recently published articles on the development of HBGS process as a technique for separation of CO2 from flue gas, feed gas and high CO2 natural gas streams are briefly reviewed
Experimental Evaluation of Chemical Reactions Involved in Ultrasonic-Assisted Absorption of Bulk CO2
No full textAs the most mature natural gas sweetening process, absorption has always been improved to meet the separation requirement. Recently, ultrasonic irradiation has been proposed as a technique that can intensify CO2 absorption. However, further studies are still required, particularly focusing on the sonochemical effect. Since the influence of the sonochemical effect on the reaction pathway is still debatable, attention must be given to verifying the influence of ultrasonic irradiation on the chemical reactions of CO2 absorption. Hence, this work aims to evaluate the influence of OH˙ radicals generated by the sonochemical effect on the chemical reactions involved during CO2 absorption using promoter-free methyldiethanolamine (MDEA). For the evaluation, various samples under irradiated and non-irradiated conditions are analyzed using the HPLC characterization technique. The results show that the hypothesis of changing the reaction pathway due to the presence of the sonochemical effect is invalid. However, it can accelerate the generation of hydroxyl radicals (OH˙) via water sonolysis. Thus, the origin of sonochemistry in aqueous solutions is defined as water sonolysis. The analysis of the CO2 absorption rate also demonstrates the presence of accelerated chemical reactions (contributed by the OH˙ radicals), which could potentially make the slow kinetic MDEA more practical for industrial application
Prediction of hydrate formation conditions based on the vdWP-type models at high pressures
No full textGas Hydrate Equilibrium Measurement of Methane + Carbon Dioxide + Tetrahydrofuran+ Water System at High CO2 Concentrations
No full textAbstractApplication of gas hydrate in separation of carbon dioxide (CO2) form nitrogen in Carbon Capture and Storage (CCS) chain is recently studied by many researchers. Tetrahydrofuran (THF) is suggested as promoter for this process. The same process can be suggested for separation of CO2 from methane (CH4) for gas treatment and sweetening, especially for high CO2 content mixtures such as landfill gas. The first step in development of such process is understanding of the phase boundary of this mixture at different pressure-temperature condition and gas/liquid composition. In this work, gas hydrate phase boundary of CH4, CO2, THF and water at different pressure from 4.5 to 8.1 MPa is experimentally measured. CO2 mole fraction in gas phase is fixed at 0.7 and THF concentration in the liquid phase set at 0.03 mole fraction. Results show that presence of THF in the mixtures shift the phase boundary to the lower pressure / higher temperature condition. This effect is favorable for industrial applications
Experimental Evaluation of a Novel Thermodynamic Inhibitor for CH4 and CO2 Hydrates
No full textAbstractIn natural gas transmission and processing, gas hydrate formation is a major flow assurance challenge which led scientists towards conducting new and more detailed studies on different aspects of gas hydrates inhibitors. Ionic liquids (IL) recently revealed as novel hydrate inhibitors due to their unique properties like electrostatic charges together with ability to form hydrogen bonding with water molecule lead them viable research area in the field of gas hydrate mitigation. This paper highlighted the experimental evaluation of thermodynamic measurements of tetra methyl ammonium hydroxide (TMAOH) for Methane (CH4) and Carbon Dioxide (CO2) gas hydrates. TMAOH belongs to ammonium based ionic liquids (AILs) which is comparatively economical ILs among the other ILs families. Traditional T-cycle technique with isochoric step heating method was adopted for determining thermodynamic inhibition in this work. Results reveal that TMAOH effectively shift the hydrate equilibrium curve to upper pressure and lesser temperature regions for CH4 + TMAOH + water system and CO2 + TMAOH + water system. The average reduced temperature obtained for CH4 + TMAOH + water system is around 1.06 oC while for CO2 + TMAOH + water system, the inhibition effect found to be around 2.09 oC. Therefore, this study provides roadmap for superior alternative for the development of novel thermodynamic hydrate inhibitor, which can efficiently control the gas hydrate formation
Determination of green solvents’ water activity by inference of freezing point depression
No full textDeep eutectic solvents (DESs) are novel green solvents with great potential in many industrial applications. Due to their high tunability, DESs can be synthesized and prepared into various concentrations by dilution with water. This work revolutionises the determination of selected DESs’ water activity using inferencing their respective freezing point depression. Using the Hildebrand-Scott equation, the freezing point depression of the respective DESs in various concentrations is then correlated to the water activity. This inferential correlation provides an alternate but convenient way of determining a solution’s water activity in absence of a water activity meter. The highest freezing point depression of almost -10 oC was observed on the choline chloride and ethylene glycol in 1:2 molar ratio DES at 50 wt% concentration, with corresponding water activity determined at 0.909.</p
Impact of gas phase composition on gas hydrate process for carbon dioxide capturing from gaseous mixtures
No full textHydrate based technology is a promising new process for separation of Carbon dioxide from different gas mixtures. The process is claimed to be less energy intensive, green and low technology. In this article effect of composition on the efficiency of such process is discussed. CSMGem software is used for analysis. Results shows that gas phase composition have important impact on the efficiency of process.</p
Experimental Investigation of Novel Green Solvents for Improving Oil Recovery through Interfacial Tension
No full textThe rise in demand for energy forces us to extract oil as much as possible. A variety of methods should be used for that categorized as primary, secondary, and tertiary techniques. Tertiary methods known as enhanced oil recovery (EOR) have been applied mostly to maturing reservoirs. To implement more efficient EOR methods, new materials and technologies should be used. Ionic liquids (IL) were highly regarded for chemical EOR in the last decade until researchers raised concerns about their cost, and environmental impacts. Recently, deep eutectic solvents (DES) were discovered and known as a potential replacement for ILs due to their non-toxic nature, biodegradable, non-flammable nature, and cost. In this study, the effectiveness of DES is investigated by observing its ability to change Interfacial tension (IFT). The studies included the effects of pressure, temperature, salinity, and concentration. The optimum salinity point was obtained as 100000ppm and after that the effect was minimal. The IFT changes with pressure change were negligible, while temperature proved to be the most affecting parameter. Overall, the study suggests that IFT changes using DES in the chemical EOR method for light crudes will not be a limiting factor at reservoir conditions
Investigation of the task oriented dual function inhibitors in gas hydrate inhibition: A review
No full textRecent advances in gas hydrate research mainly focus on dual function gas hydrate inhibitors (DF-GHIs). DF-GHIs exhibit dual behavior of shifting the hydrate dissociation curve to lower temperatures and higher pressures as well as hindering or delaying the nucleation. The main focus of this review is to discuss all the possible factors that can induce dual functionality in gas hydrate inhibitors (GHIs). In this regard, this review summarizes the latest developments, classification, evaluation techniques and experimental findings of GHIs. The experimental data of different research groups is critically analyzed and systematically evaluated in terms of average depression temperature (ΔŦ) and relative inhibition power (RIP). The ΔŦ and RIP is calculated from existing experimental data. The studies in this field will give more knowledge at both academic and industrial level for the development of economical, efficient and biodegradable DF-GHIs
