Petrochemical Engineering Research Articles

Flame retardant and antibacterial properties of PLA/PHMG‐P/APP composites

AbstractPoly(lactic acid) (PLA) has evolved into a commodity polymer with numerous applications. However, its high flammability limits its viability as a perfect alternative to petrochemical engineering plastics. In this study, PLA was modified using polyhexamethyleneguanidine phosphate (PHMG‐P) and ammonium polyphosphate (APP). The flame retardant performance of PLA/PHMG‐P/APP was investigated based on the limiting oxygen index (LOI), vertical burning test (UL‐94), thermogravimetric analysis (TGA), cone calorimetry (CC), scanning electron microscopy (SEM), Fourier‐transform infrared spectroscopy (FTIR), and Raman Spectrometry. Qualitative and quantitative methods were used to determine the antibacterial properties of PLA composites. The LOI of PLA‐10% (P:A = 1:4) was 31.7% and was rated V‐0 in the UL‐94 V‐0 test. The antibacterial properties of the composites reflected the antibacterial effects of PLA‐10% (P: A = 1:4) against Escherichia coli and Staphylococcus aureus, with the antibacterial rates reaching 93.41% and 93.26%, respectively. PHMG‐P and APP had a synergistic flame‐retardant effect and improved the flame retardancy of PLA while exhibiting excellent antibacterial properties.

Microstructure variation effects influence on characteristics and mechanical properties of Monel 400 and low alloy steel (ASTM 387-Gr.11) GTAW dissimilar joint

Monel 400 with low alloy steel dissimilar joints are widely used in oil industry, petrochemical and nuclear engineering, this kind of applications needs welding joints with good mechanical properties, stable magnetic permeability and good weldability. Difference in mechanical, chemical and physical properties between these unique alloys makes such joint difficult and joints mechanical properties and microstructure will be different from parent metals. In this study, GTAW process has been employed with ERNiCrFe-3 electrode to produce dissimilar welding joints with specifies welding procedure parameters, SEM/EDS microstructure analysis, microstructure optical test, Vickers microhardness and tensile test used to study microstructure details and its impacts on welding joint mechanical properties. Research results according to welding zone microstructure analyses shown formation of Widmanstatten ferrite structures and second phase particles with fine graine structure in low alloy steel side the formation of transion zone (TZ). Moreover, clearly fusion line (FL) clearly marked in Monel 400 side while weld metal solidification microstructure with (MGBs) and (SGBs) respectively and interdendritic microstructure observed in weld zone center. Weldment mechanical and microstructure examination indicated the ability to produce like this dissimilar joint with requirement of design criteria and indicated that the failure in like this joint excepted to be in low alloy steel side. The result and microstructure analyses of this research is very important to understanding the variation in welding zone and HAZ microstructure and its impact in weldment mechanical properties and establish the base to produced best welding procedure according to welding zone microstructure properties.

F−@d4r, a New Type of Acidic Catalytic Site in Zeolite

As a solid acid, zeolite has been widely used in many fields such as tail gas treatment, petrochemical engineering, and the fine chemical industry. F− has been widely used in the synthesis of pure silica or high silica zeolites. To balance the charge of organic structure directing agents (OSDA), F− is often found located at the center of the double-4-rings (d4r) of the as-made zeolites. During calcination, fluorine ion is removed with the OSDA. We screened a series of composition building units and found that d4r is capable to retain F− in zeolite structure. We introduce the F− back after the calcination to create an unprecedented type of acid site, i.e., F−@d4r in pure silica zeolites ITQ-12. The F−@d4r species is thermal stable up to 300 °C. ITQ-12 with F−@d4r shows substantial catalytic activity in Biginelli reaction. Furthermore, the catalytic performance is proved to be positive correlated with the presence of F−@d4r, indicating the mild acid catalytic property of F−@d4r.

Study on Interaction Capabilities of Ternary Liquid Mixtures by Thermodynamic Parameters at 308.15 K

Thermodynamic properties provide a deep and significant insight of the various interactions taking place multi component liquid mixtures especially in the field of petrochemical and reservoir engineering. The density, viscosity and ultrasonic velocity were measured experimentally for diethylmalonate (DEM) +1,4-dioxane with nitrobenzene (TM-1) and diethylmalonate (DEM) +1,4-dioxane + toluene (TM-2) at the temperature of 308.15K and atmospheric pressure over the entire range of mole fraction. The excess thermodynamic properties such as excess volume (VE), excess adiabatic compressibility (ΔKs), excess viscosity (Δɳ), excess free volume (ΔVF), excess free length (ΔLF), excess isothermal compressibility (ΔβΤ), were calculated from measured values and applied to Redlich - Kister polynomial equation to determine the appropriate coefficients. The excess or deviation properties were found to be either negative or positive depending on the molecular interactions and the nature of liquid mixtures. The deviations of the ternary mixtures from its ideal behaviour were determined in order to investigate the molecular interaction between the components of ternary liquid mixtures.

Imaging method of interfacial anomalies in layered structures

Layered structures are progressively critical to several fields like aerospace, pipeline transportation, and petrochemical engineering. However, the anomalies located on the interfaces between the layers are troublesome yet problematic to image through traditional non-destructive evaluation methods. This study presented an imaging method utilizing interface waves and visualized the interfacial anomalies in layered structures. The paper first derived and solved the dispersion equations of a layered plate. The wave structure of the interface waves and their interaction mechanisms with interfacial anomalies make them inherently sensitive to interfacial anomalies. Moreover, the interface wave modes are non-dispersive at high frequencies, causing macroscopic differences between the signals with or without abnormal features. On that basis, correlation analysis and probabilistic reconstruction formed the imaging algorithm in this work. Lastly, the experimental system was tested on two different layered metal plates. The results show that the system can precisely depict interfacial anomalies of different shapes. Especially for the circular anomalies, the produced images coincide with the pre-manufactured defects with relatively minor errors of location and area.

Quality Management Measures for Mechanical and Electrical Installation Engineering in Petrochemical Engineering Activities

Quality Management Measures for Mechanical and Electrical Installation Engineering in Petrochemical Engineering Activities

Industrial Processes Online Teaching: A Good Practice for Undergraduate Engineering Students in Times of COVID-19

The COVID-19 pandemic required higher education institutions to change the modality of face-to-face to online learning overnight. Adaptations were needed, particularly in industrial process training in Chemical Engineering and related careers. Students could not access companies and industries for internships or industrial visits, intended to allow undergraduate students to observe the process engineers’ work in professional spaces. This paper describes a pedagogical strategy to overcome this limitation. Here, we report an approach applied in an Industrial Processes course, with students from the 8th to 10th semesters and alumni, from the undergraduate Petrochemical Engineering program at Yachay Tech University (Ecuador). In this course, the students developed group projects involving an industrial process analysis focused on economic sectors of interest in the country. The projects also included a revision of official figures and statistics on production data, consumption, and perspectives of the different markets. The execution of these projects promoted students’ active participation through technical discussions by exchanging ideas. A high level of attendance at synchronic classes reflected a high motivation. Through feedback and interviews, the students’ comments confirmed the relevance and value of the strategy applied in the course.

Petrochemical Engineering Project Construction Quality Control and Technical Management

Petrochemical Engineering Project Construction Quality Control and Technical Management

Dynamic responses of corrugated cylindrical shells subjected to nonlinear low-velocity impact

Owing to high capacity of energy absorption, high compressive strength, high stiffness to weight ratio, good ductility and other excellent characteristics, corrugated structures are widely used in aerospace, civil, petrochemical engineering and other industries. These structures are often subjected to low-velocity impact during operation, which has a destructive effect on the strength and stiffness of engineering structures. However, since the process of low-velocity impact is a strongly nonlinear time-varying process, it is difficult to obtain the impact force. The present study proposes a novel computational method for nonlinear impact force in the local contact area, and analyzes the dynamic response of corrugated structures. Firstly, a new equivalent shell model of corrugated cylindrical shells is established. Afterwards, the governing equations are obtained by using the Love thin shell theory and Hamilton principle, and then turned into ordinary differential equations by the Galerkin procedure, upon which numerical solutions are achieved by the Duhamel integration and small-time increment technique. Then, numerical examples are given to illustrate validity and efficiency of the proposed method. Finally, the influence of key parameters on impact response of different types of corrugated shells is analyzed.

Safety Management Strategy of Petrochemical Engineering Project Construction

Safety Management Strategy of Petrochemical Engineering Project Construction

Application of Dual Prevention Mechanism in Petrochemical Engineering Safety Management

Application of Dual Prevention Mechanism in Petrochemical Engineering Safety Management

Выбор метода изготовления пористых порошковых изделий фильтрующего назначения

The article considers three methods of increasing the distribution uniformity of properties over the filtration area of powder filter materials at different stages of their manufacturing. It is shown that granulation of metal powders with a pore former increases the uniformity of permeability distribution over the filtration area by a factor of 2.3–3.5. Dry radial isostatic pressing ensures high distribution uniformity of properties, while the coefficient of variation of local permeability does not exceed 0.17. Radial compression allows increasing the uniformity of permeability distribution over the filtration area by 15 ... 22 % compared to that for the original powder filter materials. The selection of the method used in practice is determined by the shape, size and properties of the manufactured products and initial powders. The considered methods can be used in petrochemical engineering for the manufacture of porous powder products for filtering purposes, used to trap catalyst particles, filters for fine and coarse fuel and oil purification.

Research progress of hydrophobically modified Halloysite nanotube-based composite materials

With the development of material design theories and synthesis technologies, clay-based composite materials have been controllably prepared and successfully applied in many fields, such as biomedicine, the automotive industry, petrochemical engineering, and wastewater treatment. To date, for the preparation of clay-based composite materials, the physical and chemical properties of clay must be fully considered, including the chemical composition, crystal structure, particle size, morphology, and surface charge. Halloysite, which has a tubular crystal structure, is a curly layered aluminosilicate clay with abundant reserves and a low price for constructing composite materials. The inner and outer surfaces of halloysite nanotubes are composed of Al−OH octahedrons and Si−O tetrahedrons, respectively, which ionize in opposite ways in water, resulting in opposite charges on the inner and outer surfaces. Therefore, the selective modification of halloysite can be achieved by chemical or electrostatic adsorption of the required chemical reagent. Additionally, the modified halloysite nanotubes can be used in catalysis and the loading and release of drug molecules. Moreover, because of its nanotube structure, the halloysite can be used to construct rough structures in micro- or nano-scale. By incorporation with low-surface-energy materials, the hydrophobic halloysite-based composite materials can be prepared for self-cleaning and oil-water separation. In this review, we introduced the rational design and preparation strategies of the hydrophobic halloysite-based composite materials. Then, we summarized the applications of these prepared composite materials in oil-water separation, hydrophobic self-cleaning coating, and the loading and sustained release of drug molecules. In addition, the related mechanisms and strategies for performance improvement were systematically discussed. Finally, the existing challenges and promising future directions in this research field were proposed. The halloysite-based composite materials have enhanced properties that are highly required, including enhanced mechanical and adhesive strength, excellent scratch and wear resistance, self-healing, and higher compatibility with living organisms. We believe fruitful promising results can be achieved in this field with more effort.

Construction of First Class Applied Chemistry Specialty Characterized by Petroleum and Petro-Chemical Engineering under the Guidance of Emerging Engineering Education

Construction of First Class Applied Chemistry Specialty Characterized by Petroleum and Petro-Chemical Engineering under the Guidance of Emerging Engineering Education

Non-abrasive Finishing of Mating Surfaces of Machine Parts Using Mixed Techniques with Electromagnetic Fields Application

In various branches of mechanical engineering, faucets, valves, gate valves and other shut-off devices are manufactured and used. Their main purpose is to regulate the flow rate and direction of flows of liquid and gas media. Features of such products in the aerospace and petrochemical engineering are special strict requirements due to the specificity of their operation. These include, for example, high pressure, resistance to aggressive, fire-and explosive environments, leaks of which are unacceptable according to safety rules and environmental legislation. The design of such products, as a rule, assumes high requirements for accuracy and roughness, especially at the interface of parts, high strength in case of impact pulse effects of the fluids in them. To ensure the above characteristics, finishing abrasive treatment is most commonly used, which can result in the effect of impregnation of the surfaces of products, which will negatively affect the useful life and performance indicators of the mating surfaces. At the same time, it is obvious that mechanical finishing without any use of abrasives is extremely difficult and time-consuming. The authors of the article suggest elimination of the negative effect of impregnation by means of mixed machining techniques with the application of electromagnetic fields. Purpose. The purpose of the work is to develop a technology for non-abrasive finishing of machine parts by developing a model that allows selection or calculation of the production modes of gapless mating parts of locking devices applied in various industries. Methods. The method of the research is the use of the scientific basis of mixed machining techniques, the theory of mass transfer in electrical machining, the fundamental foundations of mechanical engineering technology, modern methods for studying characteristics at the final stages of machining, modern measuring tools, special technological equipment, as well as computer technologies. Results. As a result of the research, new technique and devices were developed. This made it possible to implement a non-abrasive finishing operation of the mating surfaces of parts made of metal materials, the processing of which by mechanical methods is difficult. Conclusion. As a result of the conducted research, it became possible to obtain high-quality high-resource gapless locking products and to reduce labor intensity of the finishing operation up to 5 times and preparation for the production up to 2 times.

TWO-LAYER STEEL FOR CRITICAL METAL STRUCTURES

The paper discusses main methods for obtaining and application of large-sized bimetal: batch rolling, electric arc welding, electroslag surfacing with subsequent rolling, explosion welding. Test results of double-layer steels sheets and experience in bimetal production prove this technology availability for critical metal structures in petrochemical and nuclear engineering or shipbuilding. The universality of the industrial explosion welding allows production of wide range bimetal compounds of 100% integrity both for a single sheet and large-tonnage lots (several hundred tons) and practically unlimited sizes. The features of heat treatment for various bimetals after explosion welding are presented.

Comparative Study of Green and Synthetic Polymers for Enhanced Oil Recovery.

Several publications by authors in the field of petrochemical engineering have examined the use of chemically enhanced oil recovery (CEOR) technology, with a specific interest in polymer flooding. Most observations thus far in this field have been based on the application of certain chemicals and/or physical properties within this technique regarding the production of 50–60% trapped (residual) oil in a reservoir. However, there is limited information within the literature about the combined effects of this process on whole properties (physical and chemical). Accordingly, in this work, we present a clear distinction between the use of xanthan gum (XG) and hydrolyzed polyacrylamide (HPAM) as a polymer flood, serving as a background for future studies. XG and HPAM have been chosen for this study because of their wide acceptance in relation to EOR processes. To this degree, the combined effect of a polymer’s rheological properties, retention, inaccessible pore volume (PV), permeability reduction, polymer mobility, the effects of salinity and temperature, and costs are all investigated in this study. Further, the generic screening and design criteria for a polymer flood with emphasis on XG and HPAM are explained. Finally, a comparative study on the conditions for laboratory (experimental), pilot-scale, and field-scale application is presented.

Cost Control of Sub-contracted Projects Based on EPC Petrochemical Engineering

EPC model is one kind of scientific and efficient petrochemical engineering management at present in our country. The EPC general contractor should effectively control the cost of sub-contracted construction projects, in the process of EPC petrochemical engineering construction. The aim is to rational use of the limited resources including human, funds and material resources, to obtain greater economic effects and social benefits for the EPC general contractor. The paper studies some impact factors of the sub-contracted projects based on EPC petrochemical engineering. And corresponding solutions are puts forward in the paper, such as paying more attention subcontract management, advocating strict control of direct expense, optimizing construction scheme, and so on. Through the above analysis, some references are hoped to provide some advantages of the cost control of sub-contracted projects for the EPC petrochemical engineering general contractor.

Judging of machining feasibility and calculation of midsection for the five-axis milling of shrouded centrifugal impeller

ABSTRACT Cavities with various geometries are widely used in the aircraft industry, spacecraft industry, ships, petrochemical engineering, and so on. As a typical example of the representative and difficult cavities, shrouded centrifugal impeller has been studied to meet the higher requirements for the high-grade advanced products. For the five-axis milling, geometric modeling parameterized by the double three-cubed Non-Uniform Rational B-Splines form of the shrouded centrifugal impeller was set up as the base of this study. The target machining cavity of the shrouded centrifugal impeller channel was calculated. The methods to judge any point in the midsection exhibiting the projection point on the inlet surface and every point in the midsection showing the projection point on the inlet surface were obtained. Moreover, the method to calculate the final midsection was proposed. For verifying these methods, the simulation of machining of a shrouded centrifugal impeller was finally proposed.

Dual In-Situ Water Diffusion Monitoring of GFRPs based on Optical Fibres and CNTs

Glass Fibre Reinforced Polymer (GRFP) composites are increasingly being used as new materials for civil and petrochemical engineering infrastructures, owing to the combination of relatively high specific strength and stiffness and cost-competitiveness over traditional materials. However, practical concerns remain on the environmental stability of these materials in harsh environments. For instance, diffusion of salty water through the composites can trigger degradation and ageing. For this reason, a continuous monitoring of the integrity of GFRP composites is required. GRFPs health monitoring solutions, being non-destructive, in-situ, real-time, highly reliable and remotely controllable, are as desirable as challenging. Herein we develop and compare two methods for real-time monitoring of GRFP: one based on the electrical sensing signals of percolated carbon nanotubes (CNTs) networks and the other on optical fibre sensors (OFSs). As a proof-of-concept of dual sensory system, both sensors were used in combination to detect the diffusion of water through the composite. Measurements demonstrated that both CNTs and OFSs were able to detect water diffusion through the epoxy matrix successfully, with an on-off sensing behaviour. OFSs exhibit some advantages since they do not require electrical supply as required in hazardous environments and are more suitable for remote operation, which make them attractive for new developments in harsh-environment sensing. On the other hand, CNTs can be easily embedded in the composite without compromising its performance (e.g., mechanical properties) and are easily interrogated by measurement of electrical conductance, therefore could be used as spot sensors in the most failure-prone sections of GFRP components. This study opens up the possibility for an early detection of composites degradation, which could prevent failures in GFRP structures such as pipelines and storage tanks used in the oil and gas industry.