Raw Natural Gas Research Articles

Natural gas sweetening using TEGMC polyimide hollow fiber membranes

Raw natural gas contains a significant range of impurities, i.e. H2S, CO2, C2, C3, C6+ etc. The acidic H2S and CO2 are especially highly corrosive to processing and transporting equipment and cause serious environmental issues. In the current study, we investigated H2S and CO2 removal efficiency of TEGMC (TriEthylene Glycol Monoesterified Crosslinked) hollow fiber membranes under realistic natural gas sweetening conditions. The membranes had been stored under ambient condition over seven years but still show good gas separation performance without any particular regeneration treatments. Unexpectedly, the presence of various hydrocarbons, i.e. C2, C3, and toluene, in the feed gas enhances both H2S/CH4 and CO2/CH4 selectivity. Indeed, the condensable hydrocarbons suppress the CH4 permeation through competitive sorption with less effect on the permeation of H2S and CO2. Such a phenomenon is unique in membrane separations, suggesting that penetrant competition can be a useful tool rather than a problem to tune the membrane performance in some cases.

A simple model for estimating hydrogen sulfide solubility in aqueous alkanolamines in the high pressure-high gas loading region

Hydrogen sulfide is essentially removed from the raw natural gas to meet the process, health, safety and environmental standards. Alkanolamine based absorption process remains the prevalent technique for hydrogen sulfide removal due to ease of operation and economic considerations. The design of such gas separation systems is a critical factor in meeting the stringent process requirements and optimizing operations. To achieve precise design, determination of vapor–liqid equilibrium for the system is indispensable while maintaining efficacy and simplicity. This study presents a simple model for estimating hydrogen sulfide solubility in aqueous alkanolamines and their blends in the high pressure-high gas loading region. The model equation is developed by considering and combining amine protonation and bi-sulfide formation reactions, assuming ideal liquid properties. Satisfactory correlated values of hydrogen sulfide loadings (0.21–3.15 mol gas/mole solvent) are obtained over a wide range of temperature (298.15–393.15 K), pressure (60–7027 kPa) and alkanolamine concentration (1.12–14.27 molal). Parameters are given for the hydrogen sulfide solubility in aqueous solutions of monoethanolamine, diethanolamine, N-methyldiethanolamine, 2-amino-2-methyl-1-propanol, piperazine, diglycolamine, di-isopropylamine, 1-amino-2-propanol and their selected blends. The model shall be useful for the design of alkanolamine based natural gas sweetening systems, operating at high pressure and high hydrogen sulfide gas loadings.

A Review on CO2 Capture Technologies with Focus on CO2-Enhanced Methane Recovery from Hydrates

Natural gas is considered a helpful transition fuel in order to reduce the greenhouse gas emissions of other conventional power plants burning coal or liquid fossil fuels. Natural Gas Hydrates (NGHs) constitute the largest reservoir of natural gas in the world. Methane contained within the crystalline structure can be replaced by carbon dioxide to enhance gas recovery from hydrates. This technical review presents a techno-economic analysis of the full pathway, which begins with the capture of CO2 from power and process industries and ends with its transportation to a geological sequestration site consisting of clathrate hydrates. Since extracted methane is still rich in CO2, on-site separation is required. Focus is thus placed on membrane-based gas separation technologies widely used for gas purification and CO2 removal from raw natural gas and exhaust gas. Nevertheless, the other carbon capture processes (i.e., oxy-fuel combustion, pre-combustion and post-combustion) are briefly discussed and their carbon capture costs are compared with membrane separation technology. Since a large-scale Carbon Capture and Storage (CCS) facility requires CO2 transportation and storage infrastructure, a technical, cost and safety assessment of CO2 transportation over long distances is carried out. Finally, this paper provides an overview of the storage solutions developed around the world, principally studying the geological NGH formation for CO2 sinks.

Analysis of the Influence of the Price of Raw Oil and Natural Gas on the Prices of Indices and Shares of the Turkish Stock Exchange

This article is a review on the impact of prices and their dependence on the cost of oil and natural gas on the world stock markets. The main studies and results achieved in the field of the impact of prices on both the stock index and industrial stocks and the dependence on the level of oil prices are presented. The paper presents an econometric study on the choice of offers on the securities market that allows us to identify the main specifics of changes in prices for the stock index and industrial shares in the daily period from 13. 05. 2012 to 01. 12. 2019. The article uses methods for estimating the impact of the price of natural gas and WTI crude oil using the Gretl statistical program, taking into account the selection of the main correlation features of the price matrix. Of the 13 proposed research models, only one model showed its statistical insignificance. A paired linear model of the CocaCola share price dependence and its dependence on NGFO prices was presented and analyzed in detail. Based on the results of econometric modeling, linear regression models were constructed for the dependence of stock prices on the NGFO and WTISPOT prices. The Gretl environment allows you to evaluate the situation in the econometric environment and make a forecast based on the obtained models of the dependence of stock prices and make appropriate conclusions.

An innovative integrated process for helium and NGL recovery and nitrogen removal

Raw natural gas is composed of several hydrocarbons, incombustible gases, such as nitrogen and helium, and impurities. While all the impurities are typically rejected at the beginning of the process, the removals of the two inert gases are postponed to last steps, where almost all the hydrocarbons except methane are already produced in an NGL recovery unit. Hence, NGL recovery, nitrogen removal and helium extraction steps are counted the most downstream units of the entire gas processing plant. This study investigates an integrated design and optimization of the three processes. In this paper, a novel process configuration, for co-production of sales gas, NGL and crude helium, is introduced. For this purpose, first we investigate and propose an efficient design to embed the helium extraction unit into a single-column nitrogen removal process. The proposed configuration is extended to an integrated process structure which combines nitrogen removal, NGL recovery and helium extraction units. The design reduces significantly the quantity of equipment as eliminating the need for the open refrigeration cycle and propane pre-cooling systems in NGL plants. High ethane and helium recovery, high nitrogen removal rate for different ranges of nitrogen, as well as the crude helium with high purity, are the outstanding potentials of the novel process. We finally optimize the key process parameters using the particle swarm optimization method to guarantee the minimum required work and present the economic evaluation of the new developed process.

Experimental High-Pressure Hydrogen Sulfide Partial Oxidation and Equilibrium Calculation by Gibbs Energy Minimization

Both H2S and CO2 are removed from raw natural gas sources for product quality and safety reasons. If a cryogenic method is used for separation, the acid gas components (H2S + CO2) may be recovered ...

RESEARCH NATURAL GAS TEMPERATURE CONTROL SYSTEM

Technological progress is characterized by continuous expansion of automation of all sectors of human activity, the transition from partial automation to integrated, and then from integrated automation to complete, which provides the highest technical and economic efficiency. The 21st century is called the information age, because the main successes of technological progress are now observed precisely in the introduction of information technology to various means and systems of automation. Automation is not possible without measuring equipment. The development of control and measurement technology for automation systems is largely determined by advances in compatible fields of science and technology - in microelectronics, computing, solid state physics, etc. It is for the developers of automation systems and control of various technological parameters that the most favorable environment of practical activity is now created in the form of a huge nomenclature of miniature and reliable sensors, which are easily combined with secondary equipment and allow to transmit measurement information over long distances in the conditions of intensive industrial interferences. Temperature measurement and control tools have long been at the forefront of automated control of many technical processes, the complication of which leads to the need for a sharp increase in the number of measurement channels to obtain complete and objective information about the temperature modes of the processes. In this regard, a computerized temperature control system for crude natural gas air coolers (APOs) is no different than sophisticated industrial automation systems. Given the fact that gas pipelines are an important part of the industrial complex of Ukraine, the development of a modern computerized temperature control system for air coolers for raw natural gas is, without doubt, an urgent scientific and technical task.

Study on Preparation and Mercury Adsorption Characteristics of Columnar Sulfur-Impregnated Activated Petroleum Coke

In order to effectively remove mercury from raw natural gas, a preparation method of columnar sulfur-impregnated activated petroleum coke was proposed and mercury adsorption experiments were conduc...

Exploring the characteristics and drivers of indirect energy consumption of urban and rural households from a sectoral perspective

AbstractChina is actively taking measures to guide the household energy‐saving consumption pattern because the total household indirect energy consumption and CO2 emissions have rapidly multiplied from 2002 to 2017 with an annual growth rate of 5.95%, and 5.56%, respectively. This paper calculates indirect energy consumption and CO2 emissions by four energy sources (raw coal, crude oil, natural gas, and electricity), analyzes the energy structure, and conducts a structural decomposition analysis in urban and rural areas in China from 2002 to 2017. The results reveal that the indirect energy consumption and CO2 emissions of urban households was 3.84 and 3.80 times, respectively, that of rural households in 2017 with most contributions from the ‘Agriculture, Forestry, Animal Husbandry, and Fishery’, ‘Foods and Tobacco’, and ‘OTHERS’ sectors. The energy consumption structure has changed. The percentage of coal consumption falls from 66.87% to 57.62%. Electricity consumption, ranked second, increased substantially from 10.77% to 22.90%. The key sectors of the energy mix have been found to help energy conservation. The high indirect energy consumption sectors with higher indirect energy intensity are the key sectors, especially the ‘Processing of Petroleum, Coking and Processing of Nuclear Fuel’ and ‘Production and Supply of Electric Power and Heat Power’. The consumption structure effect is more obvious in urban areas than in rural areas. In the process of urbanization, its effect has little impact on urban indirect energy consumption. It implies that the focus is on optimizing consumption structure rather than reducing consumption scale. © 2020 Society of Chemical Industry and John Wiley & Sons, Ltd.

Simulation and Analysis of a Petrochemical Process (Deethanizer Column- MLE field) using HYSYS Aspen Simulator

Natural gas industry has a great strategic and economic importance; it becomes one of the most attractive business opportunities in the petroleum and petrochemical field. In order to produce high quality gas, many companies all over the world including Algeria create many plants for natural gas processing to clean raw natural gas, by using separation unites and other services to get a product that respect the commercial specifications. Natural gas fractions are separated by distillation column in our case is called deethanizer tower. In this work a dynamic simulation study of deethanizer column is developed and implemented in HYSYS simulator. Simulation results prove that the HYSYS is a powerful tool to simulate industrial processes such that the simulated results are close to the real ones.

Advanced development in upstream of petroleum industry using nanotechnology

Abstract Nowadays, energy supply is one of the most important issues due to limitation of oil, gas and coal sources. Because of rapid population, civilization and energy consumption growth, the improved technologies to make optimal use of the sources, solving related problems and finding new energy sources are important. More than 10 years ago, nanotechnology as one of the most important technologies has also been applied to progress in the oil and gas industry (upstream, midstream and downstream). The experience of these years has shown that application of nanotechnology in the oil industry improves the exploration of crude oil and natural gas (underground or deep water), drilling and bringing the crude oil or raw natural gas to the surface, as well as transportation, storage, processing and purifying methods. Nanoparticles with high specific surface area, pore volume and small size show unique physical and chemical properties, which could be applied in several applications. In this regard, many researchers have been focused on various nanoparticles for upstream industries and studied their potential in oil exploration, drilling, production and enhanced oil recovery (EOR). Also, in downstream and midstream which involve refining of crude oil, processing and purifying of raw natural gas, transportation and storage of crude or refined petroleum products, the nanomaterials have been used to improve the quality of oil and make it appropriate for the environment. Lowering sulfur gasoline, enhancing the octane number and coating the transportation system are among the goals that have been achieved successfully using nanotechnology. In this work, various types of nanoparticles such as metallic, metal oxide, hybrid nanoparticles, carbon nanomaterials, nano-composites and their applications in oil upstream industry are reviewed. Also, their usage in different types of oil upstream processes is discussed.

Natural gas sweetening using a cellulose triacetate hollow fiber membrane illustrating controlled plasticization benefits

Plasticization is a well-understood drawback of polymer membranes in many applications; however, recent studies have demonstrated surprising advantages of this phenomenon for demanding natural gas sweetening for some glassy polymer dense film membranes. Moving beyond dense film membranes, the current study focuses on cellulose triacetate (CTA) hollow fiber membranes to use the benefits of controlled plasticization for realistic raw natural gas sweetening. Natural gas sweetening can be complicated by co-existence of condensable hydrocarbons, e.g. C2H6, C3H8 and toluene with the main H2S/CO2/CH4 ternary mixture; moreover, the operating temperature and pressure adds another dimension to this important separation. In this study, we consider an aggressive gas composition of high H2S (20 mol.%), low CO2 (5 mol.%), and significant amounts of C2H6 (3 mol.%) and C3H8 (3 mol.%) as well as trace amount of toluene (100–300 ppm) with CH4 comprising the rest of the feed. Various temperatures (35 °C and 50 °C) and pressures (6.9–31.3 bar) are also considered. We show a controlled plasticization benefit for the CTA hollow fiber membrane, with attractive CO2 and H2S permeance (>110 GPU) and selectivity (22–28) for CO2 and H2S over CH4 at 35 °C and 31.3 bar. The current study represents a major step forward in processes for membrane-based natural gas sweetening using practical asymmetric membranes.

Sulfolane and di-iso-propanol lean amine blend operating temperature and pressure effect to natural gas sweetening using process simulation

Blending physical and chemical solvents has shown to be promising for removing hydrogen sulfide, carbon dioxide and mercaptan from natural gas effectively. Studies show that using sulfolane and methyl di-ethylene amine blend yields better performance than traditional methods. However, the Shell process depicts that blending sulfolane with di-iso-propanol amine significantly minimizes the problem associated with amine re-circulation efficiency observed with the application of sulfolane and methyl di-ethylene amine. This study aimed at investigating the effect of temperature and pressure to the acid gas removal performance of sulfolane and di-iso-propanol lean solvent using Aspen HYSYS software. In addition, the determination of optimum blend ratio was considered. The acid gas composition of the natural gas stream was 16.9%. This is a hypothetical data used to mimic a relatively high acid gas content in a typical raw natural gas feed. During the process simulation, the lean solvent temperature and pressure were varied between 5 and 210 °C, and 20 and 250 bar, respectively, while maintaining the reactant flow rate at 819.5 kg/h. Findings informs that the optimum blend formulation obtained was 15% water, 15% sulfolane and 70% di-iso-propanol amine at operating temperature and pressure of 50 °C and 45.5 bar, respectively. At the end of the process, the acid gas composition reduced from 16.9 to 0.26%, with an increase in the methane composition by 16.12%. This was as a result of the reduction in the vapor point of the lean solvent, which significantly contributed to enhancing the contact time and efficiency between the gas feed and lean solvent. Hence, the sales gas specification for natural gas was met at lower operating temperature and pressure below 10 °C and 25 bar, respectively.

STUDY THE RELATIONSHIP BETWEEN ENVIRONMENTAL RISKS AND SOCIAL RESPONSIBILITY AND THEIR EFFECTS ON THE STOCK PRICES OF EGYPTIAN INDUSTRIAL COMPANIES: AN APPLIED STUDY

This study examines the impact of both the internal and external environmental risks of the Egyptian industrial companies on the prices of their shares on the stock exchange, in addition to studying the impact of corporate social responsibility on the prices of its shares through application to a sample of Egyptian industrial companies in the industrial sector. The study discussed the internal risks faced by industrial companies represented by their financial risks such as exchange rate liberalization, credit risk, liquidity risk, foreign exchange risk. As well as other internal risks such as occupational health and safety, strikes and labor class demonstrations. The study also discussed external risks such as unemployment, inflation, high prices of raw materials, oil and natural gas, or scarcity of raw materials, in addition to the impact of the companies' commitment to their social responsibility towards the environment and the society and its reflection on the prices of the shares of these companies in the Egyptian Stock Exchange. The objectives of the study are to study and present the quality of environmental risks in the industrial society to determine the nature of social responsibility and its relation to environmental risks, to verify the impact of the relationship between risks and to reflect social responsibility on the prices of shares of companies polluting the environment. In order to achieve the objectives of the study was used descriptive method descriptive in the study and deductive to ascertain the hypotheses of the study. The study has reached the following results: The prices of shares of industrial companies are affected by their environmental risks, showing the impact of the prices of shares of industrial companies to the degree of their social responsibility. The results also indicate the impact of the prices of shares of industrial companies on both environmental risks and social responsibility. The most important recommendations of the researchers are: the need for coordination between the industrial companies and the Ministry of Environmental Affairs to identify the environmental risks resulting from industrial processes and activities and their environmental damage, in addition to their damage to humans and other living organisms, Cooperation among agencies and ministries to raise awareness about the role of social responsibility in industrial companies and its positive impact on the environment and society, which is reflected in turn to improve its positive image and enhance its position in the community, which works to attract and retain investors, Holding conferences and seminars by inviting industrial companies to identify the most important companies that take into account the environmental dimension in their activities as well as their social responsibility and social honor locally and internationally, which increases the competition among companies towards commitment to the environmental and social role in the overall work.

Operability assessment on alternative natural gas liquids recovery schemes

Natural gas liquids (NGLs) are valuable by-products of the raw natural gas. A variety of process schemes have been developed over the years for an economical, safe and efficient extraction of these components including the conventional, cold residue recycle (CRR), and the gas subcooled process (GSP), each comprising a range of competing advantages. In this work, the operability of these NGL recovery technologies is evaluated in terms of the controllability and process dynamics. The evaluated configurations are analyzed qualitatively in order to recognize their ability of achieving main control targets and reducing the process upsets due to typical disturbances. The main goal foresees the assessment of control schemes capable of guaranteeing robustness and performance during the operation while highlighting the importance of developing a structurally sound control strategy.

A Computational Fluid Dynamics Approach for the Modeling of Gas Separation in Membrane Modules

Natural gas demand has increased rapidly across the globe in the last decade, and it is set to play an important role in meeting future energy requirements. Natural gas is mainly produced from fossil fuel and is a side product of crude oil produced beneath the earth’s crust. Materials hazardous to the environment, like CO2, H2S, and C2H4, are present in raw natural gas. Therefore, purification of the gaseous mixture is required for use in different industrial applications. A comprehensive computational fluid dynamics (CFD) model was proposed to perform the separation of natural gas from other gases using membrane modules. The CFD technique was utilized to estimate gas flow variations in membrane modules for gas separation. CFD was applied to different membrane modules to study gas transport through the membrane and flux, and to separate the binary gas mixtures. The different parameters of membrane modules, like feed and permeate pressure, module length, and membrane thickness, have been investigated successfully. CFD allows changing the specifications of membrane modules to better configure the simulation results. It was concluded that in a membrane module with increasing feed pressure, the pressure gradient also increased, which resulted in higher flux, higher permeation, and maximum purity of the permeate. Due to the high purity of the gaseous product in the permeate, the concentration polarization effect was determined to be negligible. The results obtained from the proposed CFD approach were verified by comparing with the values available in the literature.

Carbon capture and adjustment of water and hydrocarbon dew-points via absorption with ionic liquid [Bmim][NTf2] in offshore processing of CO2-rich natural gas

Offshore oil production from huge reservoirs at deep waters with high gas-oil ratio and high carbon dioxide (CO2) content is a challenging puzzle because oil extraction imposes to process a huge flow rate of raw CO2-rich natural gas from which CO2 must be separated and sent to appropriate destination. Offshore gas processing comprises three steps: water dew-point adjustment (WDPA), hydrocarbon dew-point adjustment (HCDPA) and CO2 removal to avoid transport of inert and to boost oil production by injecting CO2 into the reservoir for enhanced oil recovery. In offshore rigs, gas is conventionally treated via TEG absorption for WDPA, Joule-Thomson expansion for HCDPA and membrane permeation for CO2 removal. This work discloses a new concept of CO2-rich natural gas processing using the ionic-liquid [Bmim][NTf2] for simultaneous WDPA, HCDPA and CO2 removal. All results were obtained via rigorous simulations, including the ionic-liquid implications in vapor-liquid equilibrium and heat-effects. The main novelty of the new process is its high-pressure selective stripping of CO2, lowering compression power for enhanced oil recovery utilization. Economic comparison of conventional gas processing with the ionic-liquid gas processing shows that the latter has 19.3% higher revenues, 23.6% less manufacturing costs and 18% less investment, entailing a 37% higher net present value.

Maximizing Ether Oxygen Content in Polymers for Membrane CO2 Removal from Natural Gas.

Membrane materials for CO2 removal from natural gas are based on glassy polymers with a high CO2/CH4 diffusivity selectivity. However, these polymers suffer from competitive sorption by heavy hydrocarbons that decreases CO2 permeability and physical aging that reduces gas permeability with time. We circumvent these issues by designing rubbery, solubility-selective polymers with a ratio of ether/ester oxygen to carbon as high as 0.8 through the use of 1,3-dioxolane and 1,3,5-trioxane. The ether/ester oxygen groups interact favorably with CO2 but do not interact with CH4, leading to a high CO2/gas solubility selectivity that is unaffected by heavy hydrocarbons in the raw natural gas. These polar groups are incorporated in short branches to yield an amorphous and rubbery nature, leading to high gas permeability that is stable over time. A polymer with an O/C ratio of 0.71 (P71) shows a mixed-gas CO2 permeability of 320 Barrers and a CO2/CH4 selectivity of 21 in the simulated natural gas at 50 °C, which is independent of the hexane content and above the upper bound for CO2/CH4 separation at 50 °C.

CSB urges natural gas plant inspections

Near midnight on June 27, 2016, an uncontrolled release of methane, ethane, propane, and several other hydrocarbons occurred at the Enterprise Products Gas Plant in Pascagoula, Mississippi. The hydrocarbons ignited and the plant suffered a series of fires and explosions over the next 18 hours. No one was injured. The site subsequently shut down for almost six months. The incident cost the company $17.5 million. The incident was due to thermal degradation of a heat exchanger. Similar problems had occurred nine times over a 17-year period at Enterprise but had been corrected before a fire broke out, according to an investigation and final report by the US Chemical Safety and Hazard Investigation Board issued Feb. 13. The Enterprise plant receives raw natural gas via a pipeline from Gulf of Mexico deep-water oil wells. The plant separates the material into two products: natural gas liquids to be used as a chemical

PLA Easy Fil – White‐based membranes for CO2 separation

AbstractPolymeric membrane technology applied to gas separation is seen as a valuable alternative to conventional systems due to its ease integrability with existing plant, its lower energy consumption, and its flexibility when scaling up. It constitutes a cheaper solution because, in accordance with the principles of process intensification strategy, realized with a reduced number of stages process. In this work, for the first time, a modified polylactic acid‐based polymer (PLA Easy Fil™ – White) was used to synthesize polymeric membranes for use in CO2 separation. This has the further advantage of adopting a biodegradable and non‐toxic material and environmental friendly. Dense symmetric PLA Easy Fil™ – White membranes (average thickness ∼ 27 μm) were prepared and characterized in terms of differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and Fourier‐transform infrared (FTIR) analyses and in single gas permeation tests to determine their perm‐selectivity at room temperature in the particular field of CO2/CH4 separation as an example of CO2 removal from raw natural gas or biogas. A CO2/CH4 ideal selectivity equal to 285 (corresponding to a CO2 permeability of 70 barrer) was obtained, overcoming the related Robeson's upper bound. © 2019 Society of Chemical Industry and John Wiley & Sons, Ltd.