QIU Kang, WANG Lihua, CUI Qiang, WANG Ying, WANG Xiaoshan, XIONG Zhenyu
The Qiongdongnan Basin is located in the northwestern part of the continental shelf in the northern part of the South China Sea, which is a Cenozoic highly-overpressured, transformed, and extended basin with abundant oil and gas resources. The Qiongdongnan Basin is also a typical offshore HTHP basin in China, and is one of the world’s top 3 offshore HTHP areas, with the highest reservoir temperature of over 240 ℃ and the highest formation pressure coefficient of 2.3, which makes it one of the most difficult areas for domestic and international drilling operations. The complex genesis mechanism of abnormal high pressure in the Qiongdongnan Basin of the South China Sea results in great difficulty and low accuracy of pre-drilling pressure prediction, which seriously compromises drilling safety. Block 64/07 of Lingshui structure in Qiongdongnan Basin was taken as the research object. Through analysis of tectonic evolution and loading/unloading mechanisms, the coupling genesis mechanisms of abnormal high pressure in this block were revealed, a multi-mechanism coupling pressure prediction method was specifically established, and formation pressure profiles of drilled wells and a 3D regional formation pressure model were constructed, systematically analyzing the vertical and horizontal pressure systems of this block. The Qiongdongnan Basin has experienced many rounds of tectonic evolution since the Paleocene, forming a huge thickness of Paleocene-Neocene and Quaternary sediments. From the perspective of the depositional history of the Qiongdongnan Basin, the sedimentation rate of the whole basin is relatively high, with two distinct peaks. The first peak occurred in the fracture to fracture-argument period, with a subsidence rate exceeding 600 m/Ma. The second appeared during the post-fracture rapid subsidence period, with the Yinggehai Formation reaching 600~1 700 m/Ma. Both rates exceeded the 150 m/Ma threshold for overpressure, and these periods were prone to the formation of anomalous high pressures with undercompaction mechanisms. These processes were the basis of the overpressure prevalent across the entire basin, and were manifested as loading-type anomalous high pressures. Meanwhile, the FS fracture zone in this region had the ability to transmit oil and gas, forming a two-way hydrocarbon supply pattern between the main depression and the secondary depression in western Lingshui. The hydrocarbons had two large-scale hydrocarbon discharge periods (15 Ma and 5 Ma), and the Meishan~Sanya Formation underwent prolonged effective charging, creating conditions for high pressure caused by fluid charging, which was the most probable auxiliary cause of anomalous high-pressure formation in this region. Using the logging data of the drilled wells, the rock density-sound wave velocity crossplot of the stratified sections was established, and the Meishan Formation showed a composite mechanism of loading and unloading. Combined with the tectonic evolution history, it could be inferred that the anomalously high pressure of Yinggehai and Huangliu Formations was attributed to the undercompaction mechanisms, and the anomalously high pressure of Meishan Formation resulted from the coupling mechanism of undercompaction and fluid filling. To address the high-pressure coupling genesis mechanism of this block, this study developed a multi-mechanism coupling pressure prediction method. The upper Yinggehai Formation and Huangliu Formation under-compacted strata were evaluated using the conventional Eaton method, and the lower Meishan Formation and Sanya Formation stratigraphic over-pressure zones were analyzed using the multi-parameter effective stress method, thereby overcoming the limitations of single-method prediction and improving prediction accuracy. Based on this method, a high-precision three-dimensional stratigraphic pressure body was constructed in Lingshui tectonic block 64/07, revealing the vertical and horizontal distribution patterns of stratigraphic pressure in this block. The results showed that the high pressure in formations above Huangliu Formation in this area was caused by undercompaction mechanism, while below Meishan Formation it was caused by the coupling mechanism of undercompaction and fluid charging. Vertically, pressure began to increase in the middle and lower part of Yinggehai Formation, Huangliu Formation served as the pressure transition zone, and Meishan and Sanya Formations entered the overpressure zone, with the highest pressure coefficient reaching 2.10. Horizontally, it generally presented the characteristics of “low in the west and high in the east, low in the north and high in the south”. These research findings were applied to well L5-1. The core of this method lay in addressing the coupling genesis of formation pressure in the Meishan Formation by establishing a multi-parameter effective stress method. Parameters such as shale content, porosity, and effective stress of the lower high-pressure layer were introduced, avoiding the difficult problem of determining original sedimentary loading and subsequent unloading, thereby achieving accurate prediction of reservoir high pressure. During the drilling process of well L5-1, a combination of pre-drilling pressure prediction, logging monitoring, logging constraints on seismic layer velocity and MDT pressure correction were used to follow up and monitor the trend of pressure change throughout the entire process in real time. The entire pressure monitoring process could be divided into four stages: (1) determining the starting pressure layer at the pre-drilling design stage as the bottom of Ledong Formation and the top area of Yinggehai Formation; (2) adjusting the starting pressure depth from 2 100 m to 1 850 m based on the three-opening single-root gas pressure and the pressure monitoring profile with drilling; (3) using the four-opening electroacoustic constraints to recalibrate the extracted layer velocity, combined with the MDT pressure measurements, to correct the parameters of the prediction model; (4) conducting five-opening monitoring and the DST test after completion of drilling to complete the real drilling pressure evaluation. Using this method, the average accuracy of pre-drilling formation pressure prediction was 87.1%. During actual drilling, based on logging and test data, prediction results were timely corrected, and the prediction accuracy of lower formation pressure was improved to 98.8%, meeting the requirements for drilling design and field construction.
Petroleum refining. Petroleum products, Gas industry
Kurmet G. Satenov, Yerlan M. Suleimen, Zholaman A. Tashenov
With the rapid development of green energy and its transition to renewable sources, countries and multinational oil and gas companies are increasingly focusing on forecasting global scenarios of the world economy’s demand for hydrocarbon resources. These predictions serve as a key reference point for determining future development strategies. Gas produced from natural sources plays a key role in the global energy industry and in the international balance of fuels. The main objective of the Gas Processing Plants construction is to provide Kazakhstan consumers with high-quality sales gas and increase the stability of gas delivery at the expense of the country’s own resources. In order to meet the technical requirements for finished products, the processing trains of the plant should be equipped with inlet separators, gas dehydration units, gas sweetening unit and sour (raw) gas injection system. This article presents an overview of new gas treatment technologies used in the processes of sales gas production. The classification and brief characteristics of gas sweetening systems, including absorption, adsorption and membrane methods, are described. The different types of zeolites used in dehydration systems are also presented. Special attention is given to gas injection processes.
With growing environmental concerns, the search for alternative gases to replace SF<sub>6</sub> has become a key focus in the power industry. Perfluoromethyl vinyl ether (PMVE), with its low global warming potential (GWP) and excellent insulation properties, is a promising candidate. When mixed with N<sub>2</sub>, PMVE not only decreases the liquefaction temperature but also enhances insulation performance, making the gas mixture more suitable for engineering applications. In this study, reactive molecular dynamics (ReaxFF-MD) and density functional theory (DFT) calculations were combined to investigate the influence of temperature on the decomposition characteristics of a PMVE/N<sub>2</sub> mixture. The reaction pathways and reaction enthalpy of PMVE and its major decomposition products were analyzed in detail. The results showed that, as temperature increases, the decomposition intensity of PMVE is enhanced, leading to a higher reaction rate and accelerated formation of decomposition products. Moreover, the main decomposition products of the PMVE/N<sub>2</sub> mixture include C, C<sub>2</sub>F<sub>2</sub>, CF<sub>2</sub>, CN, CO, CF<sub>2</sub>O, F, O, and other small molecules and free radicals. The dynamic balance between the generated free radicals helps maintain the system’s insulation capacity. However, toxic decomposition byproducts such as CF<sub>2</sub>O, C<sub>2</sub>N<sub>2</sub>, and CO were also detected. This study provides valuable insights into the engineering applications of PMVE/N<sub>2</sub> mixtures.
This study examines the geopolitical crises in Ukraine and Taiwan using a qualitative and comparative approach and analyzes the role of various components of the geography of power, including ethnic and religious compositions, strategic location, natural resources, and human dimensions (human rights), in the formation and escalation of these crises. The findings show that in Ukraine, the ethnic and linguistic compositions in the east of the country, the strategic location as a bridge between Russia and the West, and rich natural resources such as gas and agricultural land have directly contributed to geopolitical competition and have led to foreign interventions. In Taiwan, although the ethnic composition is less diverse, the identity distinction of the Taiwanese from the Chinese and its strategic location in the vital waterways of the China Sea have made this island one of the most sensitive points in the geopolitical confrontations between China and the United States. Also, Taiwan’s role in the semiconductor industry as a strategic resource in the global technology supply chain has strongly influenced international competition. Furthermore, human rights issues have been used as political tools in both crises to justify international interventions and support. This research shows how geographical, identity, and natural resource factors have played a role in exacerbating geopolitical crises and have become tools to advance the goals of great powers.
Active carbons obtained from various carbon-containing materials are highly porous carbon adsorbents with a developed internal surface. Particular attention should be paid to large-tonnage waste from the wood-chemical industry and agriculture, as well as wood processing. Such waste includes charcoal, lignin, sawdust and chips, pieces of bark, straw and husks from the processing of finished products, nut shells, fruit pits, and leaves of fruit trees. The porous substance obtained from wood raw materials has a high adsorption capacity, as well as a large specific surface area. In the course of the deep processing of brown algae at the Arkhangelsk Seaweed Factory, a large amount of organic waste is generated. The aim of the work has been to obtain active carbons from alginate waste consisting of 70 % wood flour. For this purpose, the method of thermochemical activation with sodium hydroxide as an activating agent has been used. The initial raw material has had a moisture content of 76 % and a diverse composition of mineral and organic substances. The research has been carried out as a planned experiment. The design chosen has been a 2nd-order central composite rotatable one for 3 factors. The independent variables have been the sodium hydroxide dosage, pyrolisis temperature and its duration. Based on the results of the study, the optimal values of these factors for obtaining active carbons from algal waste have been determined, as well as the optimal parameters affecting the sorption capacity and porous structure of active carbons. The work is of practical importance, since active carbon in powder and granular forms is actively used in various industries, including pharmaceutical, food, distillery, gas purification, wastewater treatment, biomedicine, and can also be used in agriculture as agricultural sorbents and soil improvement components. Based on the results of the research, it can be concluded that the use of organic waste as a raw material for the synthesis of active carbon by thermochemical activation with sodium hydroxide is of great interest.
Felister Dibia, Chinedu Dibia, Hom Nath Dhakal
et al.
The petroleum industry has been a key driver in the development of the world economy yet continues to attract increasing criticism due to its negative environmental impact via greenhouse gas emissions, resource inefficiency, and waste. Integrating lean and green practices is fast becoming a transformative approach to tackling these issues as it integrates process optimization with sustainability principles. This review paper examined the existing literature on lean and green integration, highlighting its benefits, models, critical success factors, and a roadmap for its implementation. Also, it identified sustainability challenges and offered strategic solutions. The findings showed that integrating lean and green offers potential for both process optimization and waste and carbon footprint reduction, particularly for the petroleum industry in Sub-Saharan Africa (SSA). This can be achieved by using appropriate tools and models. Sustainable value stream mapping (Sus-VSM) is a strategic tool that highlights the importance of sustainability metrics. These sustainability metrics address the implementation challenges of the convectional value stream mapping tool (VSM). This paper is one of the few initiatives to promote lean–green integration within the petroleum industry.
Directions for the technical and technological development of aluminium industry, existing and promising projects to reduce the energy consumption and the environmental impact are analyzed. The active participation of the state in the organization of financial instruments for the ecological reconstruction of obsolete production facilities is discussed. In spite of the fact that the technology of aluminium pots is developed towards the increase of a single capacity, but with limited potential of reducing energy consumption and greenhouse gases emission, the possibilities for the increase of specific output are practically non-existent. Therefore, such projects like pots, equipped with inert anodes and drained cathodes arise and are under development, the successful completion of which is unlikely after multi-year researches and pilot tests. To continue the works related to inert anodes the decisive answer about the industrial safety of local sources of the massive oxygen emissions to atmosphere is required from competent entities. The drained cathode project, after discussing the existing problems, seems unfeasible. As opposed to the existing technology the development of the pots with vertical electrodes offers great opportunities to the designs of inert anodes and drained cathodes. Positive results of using shaped electrodes, homogenizing their surface and developing the methods for the synthesis of composite cathodes directly during the electrolytic process were obtained in laboratory conditions. It is expected that the combination of these trends and the successive dimensional scaling shall allow using the vertical electrodes at the next level for the fold increase of specific pot capacity and for the decrease of energy consumption and greenhouse gas emissions.
Dmitrii Pereponov, Alexandra Scerbacova, Vitaly Kazaku
et al.
To increase the oil recovery factor (RF), enhanced oil recovery (EOR) methods are applied: chemical, gas, thermal, and combined ones. Standard laboratory research methods for selecting and optimizing EOR technologies require a lot of time and resources, as well as core material, which is often in short supply. To optimize the selection of reagents and field development technologies, the use of microfluidic technology is proposed i.e. conducting experiments in reservoir conditions using microfluidic chips with a porous structure, reproducing the properties of the core of the target field. The main advantages of conducting tests in micromodels are the low duration and the ability to visualize filtration processes, which makes it possible to evaluate the behavior of fluids in reservoir conditions. This paper considers the modern application of microfluidics for the selection of EOR agents and stimulation methods and the status of this technology in the oil and gas industry. The use of microfluidic chips for screening surfactants and polymers, as well as studying the mechanism of low-mineralized water action is described. Conducting microfluidic tests to optimize gas and thermal EOR, which became possible due to the development and improvement of technology, is considered.
Pranay Chakraborty, Eva Borras, Maneeshin Y. Rajapakse
et al.
Analysis of volatile organic compounds (VOCs) can be an effective strategy to inspect the quality of horticultural commodities and following their degradation. In this work, we report that VOCs emitted by walnuts can be studied using gas chromatography-differential mobility spectrometry (GC-DMS), and those GC-DMS data can be analyzed to predict the rancidity of walnuts, i.e., classify walnuts into grades of freshness. Walnut kernels were assigned a class n depending on their level of freshness as determined by a peroxide assay. VOC samples were analyzed using GC-DMS. From these VOC data, a partial least square regression (PLSR) model provided a freshness prediction value m, which corresponded to the rancid class n when m=n±0.5. The PLSR model had an accuracy of 80% to predict walnut grade and demonstrated a minimal root mean squared error of 0.42 for the m response variables (representative of walnut grade) with the GC-DMS data. We also conducted gas chromatography-mass spectrometry (GC–MS) experiments to identify volatiles that emerged or were enhanced with more rancid walnuts. The findings of the GC–MS study of walnut VOCs align excellently with the GC-DMS study. Based on our results, we conclude that a GC-DMS device deployed with a pre-trained machine learning model can be a very effective device for classifying walnut grades in the industry.
Lindomar Matias Gonçalves, Clara Mendoza-Martinez, Elém Patrícia Alves Rocha
et al.
Steel is a crucial industrial product with applications in various sectors, such as construction, engineering, and industry. However, the steel industry generates significant waste, contributing to greenhouse gas emissions and environmental challenges. To address this issue, incorporating solid waste, especially sludge with high moisture content, into the steel industry’s operations is essential. This study aimed to construct and test an active indirect solar dryer for reducing the moisture content of sludge from a steel drawing industry. By employing principles of the circular economy and the environmental, social, and governance concept, the drying process showed promising results, achieving approximately 42% moisture reduction. This study involved collection and characterization of industrial sludge, design and assembly of a hybrid active indirect solar dryer, fluid dynamic analysis of the behavior of the air inside the device through CFD Ansys software 2012, tests with a thermographic camera to validate the simulation, and optimization of the sludge drying by calculating the thermal efficiency and drying efficiency of the equipment. The adoption of such drying processes can lead to substantial cost reductions in the transportation, handling, and landfilling of steel-drawing sludge, promoting innovation and aiding global steel industries in achieving their solid waste disposal targets.
Abstract The transition of the manufacturing industry towards carbon neutrality requires a reduction of the emissions from combustion for the supply of process heat. Heat pumps are an efficient alternative technology for supplying heat while improving the overall efficiency and shifting to potentially carbon neutral electricity. The state-of-the-art technology is limited to supply temperatures between 100 °C and 150 °C because of lower efficiency and component limitations. This paper has therefore analyzed two promising concepts for higher supply temperatures and found technically and economically feasible solutions for process heat supply of up to 280 °C. These solutions are using large-scale equipment from oil and gas industries for applications in energy-intensive industries. The suggested systems benefitted from the economy of scale and access to low electricity prices. The concepts outperformed a biogas-based solution, and they were competitive with biomass or natural gas systems with respect to economic performance. It was concluded that an electricity-based heat supply is possible for a wide range of industrial applications and accordingly represents an important contribution to fulfilling the objectives of lower climate impact of energy supply in industry.
The salt rock resource in China is characterized with multiple interlayers, thin salt formation and poor purity. Meanwhile, the conventional single vertical cavern has small volume and low utilization rate of salt formation, which cannot meet the requirements of rapid and efficient storage construction. Multi-step horizontal leaching can improve the utilization rate of salt formation and is suitable for constructing large gas storage in thin salt beds, and the cavern shape is a key factor affecting its volume and stability. Therefore, a physical simulation experiment was performed for the characteristics of horizontal leaching herein. Meanwhile, the effect of leaching parameters such as leaching rate, brine discharge position and back-step length on cavern shape and brine discharge concentration was explored. The results show that the large leaching rate and the high brine discharge position can reduce the brine concentration, and the effect is more significant in the early leaching stage. The small step length will form a hump cavern roof, while the large step length and use of blanket will form a flat cavern roof, and the alternate injection by two wells will form large body at both ends and small body in the middle. The cavern shape obtained by experiment is basically consistent with the numerical simulation result, which verifies the accuracy of experiment result. In addition, reference values were provided for such parameters as leaching rate and step length of multi-step horizontal leaching on site based on the experiment results, so as to build a hump-shaped horizontal cavern, further improving the stability and gas storage capacity of cavern.
Abstract The present study is focusing on the investigation, for the cement industry, of the post-combustion CO2 capture process using amine(s)-based solvents. The novel aspect of the work is the flue gas considered, namely the high CO2 contents (between 20 and 60 vol.%), representative of flue gases coming from oxygen-enriched air combustion process (also called partial oxy-fuel combustion). Using the results of preliminary solvents screening tests at laboratory scale, absorption-regeneration micro-pilot experiments were carried out for the best solvents in order to characterize their respective absorption and regeneration performances. The use of the activated solution of DEA (diethanolamine) 30 wt.% with PZ (piperazine) 5 wt.% led to particularly high absorption performances in all CO2 concentration range. Besides the experimental measurements, Aspen Hysys™ simulations of the micro-pilot tests were performed for three solvents (monoethanolamine (MEA) as the reference case, then PZ and DEA + PZ) to validate the models implemented. Finally, the validated models were used to perform industrial scale simulations. These simulations confirmed that both the regeneration energy, the equivalent work and the operating costs are reduced when the absorption-regeneration process is implemented to flue gases with high CO2 contents.
Abraham Ighoro Ebunu, Yusuf Afolabi Olanrewaju, Oghenerume Ogolo
et al.
Barite is a non-metallic mineral which is simply barium sulfate (BaSO4) and is largely used by the oil and gas industry as a weighting agent in drilling mud during drilling operations. The specific gravity of barite should range from 4.1 to 4.6 to be applicable as a drilling mud additive. This study considered the occurrence, utilization and challenges facing the mining of barite in Nigeria. It also discussed the global reserve, production and consumption of barite and types of barite ores and associated minerals in Nigeria. With the use of data from various ministries, departments and agencies involved in the records of operations within the Nigerian solid minerals sector, the nature of occurrence of barite in Nigeria has been reviewed. The various reported deposits areas have been elucidated while the associated minerals along with the quality reserve estimates have been discussed. Reported geochemical and geological studies of the barite mineralization in Nigeria show cream to grey, reddish-brown, whitish and pinkish varieties. The quality of the Nigerian barite is moderate to high. It is often associated with dolomite, fluorite, quartz, calcite, etc. The major impurities found in the mineral are iron oxide (goethite), quartz, and carbonates of magnesium, iron and calcium. Enumeration of the challenges facing the exploitation of the mineral has been revealed to include poor infrastructural development, safety and security, insufficient geophysical and geoscience data information and crude mining techniques. The barite production industry still has a huge potential for growth if these challenges are addressed.