This document contains digital supplementary material (detailed model description, parameters for different case studies and figure of exemplary waste heat supply and heat demand) related to the article "A Data-Driven Conceptual Approach to Heat Pump Sizing in Chemical Processes with Fluctuating Heat Supply and Demand" which is submitted to the peer reviewed conference proceeding of the 35th European Symposium on Computer Aided Process Engineering (ESCAPE 35).

This document contains digital supplementary material (model validation, flowsheets and detailed simulation/optimisation results) related to the article entitled “Modelling of a Heat Recovery System (HRS) Integrated with Steam Turbine Combined Heat and Power (CHP) Unit in a Petrochemical Plant”, which is part of the peer reviewed conference proceeding of the 35th European Symposium on Computer Aided Process Engineering (ESCAPE 35).

This document is supplementary information for the article titled Materials-Related Challenges of Energy Transition, submitted to the ESCAPE 35 conference. It contains the data used in the calculations and referenced in the main article.

This code is of a Non-Convex Mixed Integer Quadratic Programme of a hydrogen export facility. This programme is a multistage stochastic model, using inheritance based indexing in order to account for the influence of uncertainty in weather forecasting on the optimal scheduling of the export facility.

For mitigating global warming, polymer electrolyte membrane fuel cells have become promising, clean, and sustainable alternatives to existing energy sources. To increase the energy density and efficiency of polymer electrolyte membrane fuel cells (PEMFC), a comprehensive numerical modeling approach that can adequately predict the multiphysics and performance relative to the actual test such as an acceptable depiction of the electrochemistry, mass/species transfer, thermal management, and water generation/transportation is required. However, existing models suffer from reliability issues due to their dependency on several assumptions made for the sake of modeling simplification, as well as poor choices and approximations in material characterization and electrochemical parameters. In this regard, data-driven machine learning models could provide the missing and more appropriate parameters in conventional computational fluid dynamics models. The purpose of the present overview is to expl... [more]

Ultralow-temperature fluids (such as liquid nitrogen, liquid CO2) are novel waterless fracturing technologies designed for dry, water-sensitive reservoirs. Due to their ultralow temperatures, high compression ratios, strong frost heaving forces, and low viscosities, they offer a solution for enhancing the fracturing and permeability of low-permeability reservoirs. In this study, we focus on the combined effects of high-pressure fluid rock breaking, low-temperature freeze-thaw fracturing, and liquid-gas phase transformation expansion on coal-rock in low-permeability reservoirs during liquid nitrogen fracturing (LNF). We systematically analyze the factors that limit the LNF effectiveness, and we discuss the pore fracture process induced by low-temperature fracturing in coal-rock and its impact on the permeability. Based on this analysis, we propose a model and flow for fracturing low-permeability reservoirs with low-temperature fluids. The analysis suggests that the Leidenfrost effect an... [more]

The unregulated discharge of synthetic dyes from various anthropogenic and industrial activities has resulted in the contamination of different environmental compartments. These dyes can contaminate water bodies, soil, and even the air, resulting in many environmental and health issues. True colors may persist for long periods, thereby affecting the aesthetics and ecology of dye-contaminated areas. Furthermore, they pose potential risks to aquatic life and human health through the ingestion or absorption of dye-contaminated water or food. Acid orange 7 (AO7) is a synthetic azo dye used in the textile, tanning, food, pharmaceutical, paint, electronics, cosmetics, and paper and pulp industries. AO7 can have various human health implications, such as dermatitis, nausea, severe headache, respiratory tract irritation, and bone marrow depletion, due to its high toxicity, mutagenicity, and carcinogenicity. Efforts to regulate and mitigate dye pollution (AO7) are crucial for environmental sust... [more]

TI−6AL−4V alloys are widely used in various fields owing to their excellent corrosion resistance, high-temperature resistance, and low-temperature toughness. Herein, a microgroove fixture was used to simulate the microgrooves in a titanium alloy with different aspect ratios to study the influence of the electrolyte flow rate on the polishing effect. The optimization of the electrochemical polishing parameters was conducted using experiments and simulations. The effects of process parameters, such as the concentration of sodium chloride (NaCl) and zinc chloride (ZnCl2), polishing time, and processing voltage, on the quality of the post-polished surface were studied. Experiments were conducted on microgrooves with different aspect ratios under the optimized polishing process parameters. Changes in the surface elements of the microgrooves after polishing were detected. The experimental results indicated that the optimal electrochemical polishing solution flow rate, NaCl concentration, ZnC... [more]

As a new type of aftertreatment technology, non-thermal plasma (NTP) can effectively decompose the particulate matter (PM) deposited in diesel particulate filters (DPFs). In this paper, a regeneration test of a DPF loaded with carbon black was carried out using an NTP injection system, and the changes of oxidative activity, elemental content, and occurrence state, microstructure and graphitization degree of carbon black were analyzed to reveal the evolution of the physicochemical properties of carbon black at different regeneration stages of the DPF regenerated by NTP. As the regeneration stage of the DPF advanced, Ti, Tmax, and Te of the carbon black at the bottom of the DPF decreased, which were higher than those at the regeneration interface. After the NTP reaction, the proportion of C element decreased to less than 80%, while the proportion of O element increased to more than 20%; C-O was converted to C=O and the relative content of C=O increased. The average microcrystalline lengt... [more]

The field of material sciences has evolved vastly in the last two decades, largely due to the discovery of carbon nanomaterials such as graphene and its derivatives. Although they offer positive characteristics, the cost of production and material processing of these carbon nanomaterials has limited their application. However, scientists have started searching for cheaper and more environmentally friendly alternatives. Biochar, a carbonaceous material derived from biowaste, is the most viable alternative, as it offers characteristics on par with traditional carbon nanomaterials. This review will discuss the production of biochar from biomass, methods of production, the effects various conditions have on the production of biochar, biomass selection, current biochar applications, and the potential biochar has to produce hydrogen as an energy carrier.

For chemical processes, dynamic optimization is employed for process transition. On the basis of the multilayer control structure, the employment of dynamic optimization is affected by the regulatory control system. To avoid the adjustment of the regulatory control system, set-point optimization is proposed. For comparison, two types of optimization models, namely direct optimization and set-point optimization, are formulated. The superiority of set-point optimization is rigorously proven. By simulating the commercial process of a throughput-fluctuating ethylene column, the integrated absolute error and maximum deviation of product quality are reduced by more than 150% with set-point optimization. The results indicate that the approach to process transition via regulatory controllers not only avoids the insecurity caused by the switching of set-point controllers but also improves the optimization performance. In conclusion, the proposed optimization structure, namely set-point optimiza... [more]

Air pollution from combustion processes is harming human health and the environment. To mitigate this, one needs to adopt cleaner energy production methods, in particular, to optimize combustion systems in order to minimize pollutants and increase efficiency. Flue gas analysis and particulate matter (PM) monitoring, starting from the prototype phase, is crucial to minimize and regulate pollutant emissions. This article analyses the emissions of pollutants and particulate matter from a combustion test gasifier working on the Top-Lit Updraft (TLUD) principle in order to optimize functionality and reduce exhaust emissions. Three experiments were performed in which the primary (gasification) air flow rate (GA) was kept constant at 25 L/min, and the secondary (combustion) air flow rate (CA) was adjusted to obtain a CA/GA ratio of 2 (50 L/min), 3 (75 L/min), and 4 (100 L/min) respectively. Based on a multi-criterial analysis, the optimal CA/GA ratio for TLUD combustion is 3, offering a well-... [more]

Hydraulic fracturing is one of the most effective stimulation methods for unconsolidated sandstone reservoirs. However, the design of hydraulic fracturing must take into account the mechanical and stress properties of different geological formations between layers. In this paper, a three-dimensional coupled fluid-solid model using the finite element method is developed to investigate multiple vertical fractures at different depths along a vertical wellbore under different geological and geomechanical conditions. The finite element model does not require further refinement of any new cracks, requiring much smaller degrees of freedom and higher computational efficiency. In addition, new elements were used to account for local pressure drop due to perforation entry friction along the vertical wellbore. Numerical simulation results indicate that hydraulic fracture connections are observed from adjacent layers. Furthermore, the low stress contrast and high Young’s modulus between the layers... [more]

Renewable sources of energy production are some of the main targets today to protect the environment through reduced fossil fuel consumption and CO2 emissions. Alongside wind, solar, marine, biomass and nuclear sources, hydropower is among the oldest but still not fully explored renewable energy sources. Compared with other sources like wind and solar, hydropower is more stable and consistent, offering increased predictability. Even so, it should be analyzed considering water flow, dams capacity, climate change, irrigation, navigation, and so on. The aim of this study is to propose a forecast model of hydropower production capacity and identify long-term trends. The curve fit forecast parabolic model was applied to 33 European countries for time series data from 1990 to 2021. Space-time cube ArcGIS representation in 2D and 3D offers visualization of the prediction and model confidence rate. The quadratic trajectory fit the raw data for 14 countries, validated by visual check, and in 20... [more]

To address the challenge of quickly and efficiently accessing relevant management experience for a wide range of ground engineering construction projects, supporting project management with information technology is crucial. This includes the establishment of a case database and an application platform for intelligent search and recommendations. The article leverages Optical Character Recognition (OCR) technology, knowledge graph technology, and Natural Language Processing (NLP) technology. It explores the mechanisms for classifying construction cases, methods for constructing a case database, structuring case data, intelligently retrieving and matching cases, and intelligent recommendation methods. This research forms a complete, feasible, and scalable method for deconstructing, storing, intelligently retrieving, and recommending construction cases, providing a theoretical basis for the establishment of a construction case database. It aims to meet the needs of digital project managem... [more]

In order to enhance the heat transfer performance of a phase change thermal energy storage unit, the effects of trapezoidal fins of different sizes and arrangement modes were studied by numerical simulation in the heat storage and release processes. The optimal enhancement solution was obtained by comparing the temperature distribution, instantaneous liquid-phase ratio, solid−liquid phase diagram and comprehensive heat storage and release performance of the thermal energy storage unit under different fin sizes. During the heat storage process, the results show that when the ratio of the length of the upper and lower base of the trapezoid h1/h2 is 1:9, the heat storage time is shortened by 9.03% and 18.21% compared with h1/h2 = 3:7 and 5:5, respectively. During the heat release process, the optimal heat transfer effect is achieved when h1/h2 = 5:5. To further improve the heat transfer effects, the energy storage unit is placed upside down; then, the least time is achieved when h1/h2 = 2... [more]

HSG (high-sulfur gas) reservoirs are prevalent globally, yet their exploitation is hindered by elevated levels of hydrogen sulfide. A decrease in temperature and pressure may result in the formation of sulfur deposits, thereby exerting a notable influence on gas production. Test instruments are susceptible to significant corrosion due to the presence of hydrogen sulfide, resulting in challenges in obtaining bottom hole temperature and pressure test data. Consequently, a WTD (wellbore temperature distribution) model incorporating sulfur precipitation was developed based on PPP (physical property parameter), heat transfer, and GSTP (gas−solid two-phase) flow models. The comparison of a 2.53% temperature error and a 4.80% pressure error with actual field test data indicates that the established model exhibits high accuracy. An analysis is conducted on the impact of various factors, such as production, sulfur layer thickness, reservoir temperature, and reservoir pressure, on the distributi... [more]

The Occupational Health and Safety system enforces the continual improvement culture in industries for much safer processes and zero injuries. The Quality Management System also enforces the same philosophy of continual improvement within the processing system for zero defects, hence a high productivity rate. Good quality products always result from good Overall Equipment Effectiveness; hence, Process Re-Engineering is essential for the good functioning of machinery. This research is based on Integrated Management System requirements in terms of problem-solving, especially the opportunities that arise within Quality nonconformances, Safety Incidents, as well as Process Engineering related breakdowns. This study aims to develop a troubleshooting system that evaluates continual improvement projects. The method used to develop the troubleshooting system is based on Total Quality Management, where lean principles are combined with kaizen concepts and quality standards. The proposed trouble... [more]

The rapid expansion of the scale of wind power has led to a wave of efforts to decommission wind turbine blades. The pyrolysis of decommissioned wind turbine blades (DWTBs) is a promising technological solution. Microwave pyrolysis offers the benefits of fast heating rates and uniform heat transfer, making it a widely used method in various heating applications. However, there are few studies on the microwave pyrolysis of DWTBs, and pyrolysis characteristics under different boundary conditions remain unclear. In this paper, we investigate the pyrolysis characteristics of DWTBs by utilizing silicon carbide (SiC) particles as a microwave absorbent. The results demonstrated that, when the microwave heating power increased from 400 W to 600 W, the heating rate and pyrolysis final temperature of the material increased, resulting in a reduction in pyrolysis residual solid yield from 88.30% to 84.40%. At 600 W, pyrolysis gas components included C2H4, CH4, and CO, while the tar components incl... [more]

The Acosta method involves rewiring the yeast metabolic pathway to enhance biomass production and prevent a significant increase in higher alcohols during the late stages of fermentation. This study aimed to assess fermentation conditions to achieve Cuban schnapps with reduced concentrations of higher alcohols and replicate the process on an industrial scale. To achieve this, the quality of final sugarcane molasses for fermentation by Saccharomyces cerevisiae (S. cerevisiae) yeast was evaluated. Industrial pre-fermentation and fermentation processes were successfully conducted, followed by laboratory-scale fermentation using the Acosta fermentation method to determine crucial parameters for industrial implementation. Operational parameters for fermentation were identified from the following results: 13.5 °Brix seeding, metabolic pathway inversion of S. cerevisiae at 16 h, and an air concentration of 0.1 m3/min. The resulting Cuban schnapps obtained using this method exhibited a concent... [more]

The stress and fatigue of the runner during the operation of the large Kaplan turbine are one of the key issues in the operation of turbines. Due to the complexity of the working load and the geometric configuration of the Kaplan turbine runner, the different contact modes between the internal components of the runner will have an impact on the stress and fatigue results. Therefore, the unsteady CFD calculation of the full channel is conducted in this article to analyze the hydraulic characteristics of the turbine blades in the unsteady flow field, such as pressure and torque. The pressure load is loaded onto the runner using a fluid−structure interaction (FSI) theory, and the stress characteristics of the blade, blade lever, and runner body are compared under three contact modes. Based on the dynamic stress spectrum of the blade lever calculated under three contact conditions, the life of the blade lever is predicted using the rain flow counting method and the Palmgren−Miner theory. T... [more]

During the temporary plugging fracturing (TPF) process, the pressure response and pumping behavior significantly differ from those observed during conventional fracturing fluid pumping. Once the temporary plugging agent (TPA) forms a plug, subsequent fracture initiation and propagation become more intricate due to the influence of the TPA and early fractures. Factors such as concentration, particle size, and ratio of the TPA notably affect the effectiveness of TPF. This study employs a true triaxial hydraulic fracturing simulation system to conduct TPF experiments with varying particle size combinations and concentrations at both in-fracture and in-stage locations. The impact of different TPA parameters on the plugging effectiveness is assessed by analyzing the morphology of the induced fractures and the characteristics of pressure curves post experiment. Results indicate that combining dfferent particle sizes enhances plugging effectiveness, with a combination of smaller and larger pa... [more]

Radial wellbore fracturing is a promising technology for stimulating tight sandstone reservoirs. However, simultaneous fracturing of multiple radial wellbores often leads to unsuccessful treatments. This paper proposes a novel technology called multi-stage radial wellbore fracturing (MRWF) to address this challenge. A numerical model based on the finite element/meshfree method is established to investigate the effects of various parameters on the fracture propagation of MRWF, including the azimuth of the radial wellbore, the horizontal stress difference, and the rock matrix permeability. The results show that previously created fractures have an attraction for subsequently created fractures, significantly influencing fracture propagation. A conceptual model is proposed to explain the variations in the fracture propagation of MRWF, highlighting three critical effect factors: the attraction effect, the orientation effect of the radial wellbore, and the deflection effect of the maximum ho... [more]

As a key system in nuclear power plants, nuclear power systems contain high-temperature, high-pressure water media. A steam leak, if it occurs, can at minimum cause system functional loss and at worst lead to casualties. Therefore, it is urgent to carry out steam leakage detection work for high-temperature, high-pressure loop systems. Currently, steam leaks are primarily detected through visual monitoring and pressure gauges. However, if there is a minor leak under high system pressure, the slight decrease in pressure may not be enough to alert the operators, leading to a delay in detecting the steam leak. Thus, this detection method has certain drawbacks. In view of these issues, this paper introduces computer vision technology to monitor the high-temperature, high-pressure loop system and proposes the use of an improved background subtraction method to detect steam leaks in the loop system. The results show the following advantages of this method: (1) It can effectively identify stea... [more]

In order to solve the cold-starting problem and improve the intake and exhaust pipe temperatures of diesel engines under cold-starting and low- and medium-speed conditions, this paper proposes a twice-open control method for a hydraulic variable valve system. First, a hydraulic variable valve system that can realize a fully variable valve lift and phase angle is applied to replace the original intake system in order to meet the air intake requirements of different conditions. Then, a twice-open control method in which the intake valve opens two times at the exhaust stroke and intake stroke is proposed to improve the intake pipe temperature and solve the cold-starting problem. This paper contains a numerical work analysis. A GT-POWER model is constructed to validate the intake valve twice-open control method. The cylinder pressure, cylinder temperature, intake pipe pressure, and intake pipe temperature are obtained and compared between the original intake valve system and the hydraulic... [more]