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The process integration and electrification concept has significant potential to support the industrial transition to low- and net-zero-carbon process heating. This increasingly essential concept requires an expanded set of process analysis tools to fully comprehend the interplay of heat recovery and process electrification (e.g., heat pumping). In this paper, new Exergy Pinch Analysis tools and methods are proposed that can set lower bound work targets by acutely balancing process heat recovery and heat pumping. As part of the analysis, net energy and exergy load curves enable visualization of energy and exergy surpluses and deficits. As extensions to the grand composite curve in conventional Pinch Analysis, these curves enable examination of different pocket-cutting strategies, revealing their distinct impacts on heat, exergy, and work targets. Demonstrated via case studies on a spray dryer and an evaporator, the exergy analysis targets net shaft-work correctly. In the evaporator case study, the analysis points to the heat recovery pockets playing an essential role in reducing the work target by 25.7%. The findings offer substantial potential for improved industrial energy management, providing a robust framework for engineers to enhance industrial process and energy sustainability. [ABSTRACT FROM AUTHOR]

In this research, the simulation of an existing 31.5 MW steam power plant, providing both electricity for the national grid and hot utility for the related sugar factory, was performed by means of ProSimPlus® v. 3.7.6. The purpose of this study is to analyze the steam turbine operating parameters by means of the exergy concept with a pinch-based technique in order to assess the overall energy performance and losses that occur in the power plant. The combined pinch and exergy analysis (CPEA) initially focuses on the depiction of the hot and cold composite curves (HCCCs) of the steam cycle to evaluate the energy and exergy requirements. Based on the minimal approach temperature difference (∆Tlm) required for effective heat transfer, the exergy loss that raises the heat demand (heat duty) for power generation can be quantitatively assessed. The exergy composite curves focus on the potential for fuel saving throughout the cycle with respect to three possible operating modes and evaluates opportunities for heat pumping in the process. Well-established tools, such as balanced exergy composite curves, are used to visualize exergy losses in each process unit and utility heat exchangers. The outcome of the combined exergy–pinch analysis reveals that energy savings of up to 83.44 MW may be realized by lowering exergy destruction in the cogeneration plant according to the operating scenario. [ABSTRACT FROM AUTHOR]

The aim of the study was to assess the external and internal compatibility of the Biometrics E-LINK EP9 evaluation system device in the area of hand grip and pinch strength in the Polish population. The testing of hand grip and pinch strength was carried out among 122 healthy students. Two examiners performed hand grip and pinch strength measurements with a Biometrics E-LINK EP9 evaluation system device. Measurements were made for the right and left hands. The same people were tested again two weeks later, under the same conditions. The scores of one rater on the first and second tests were compared for reproducibility, and the scores of the two raters were compared to assess the reliability of the instrument. The measurements were found to be highly consistent both between the investigators and between the tests in the hand grip dynamometer test. The findings show high values of the Pearson's correlation coefficient equal or close to 1, as well as the interclass correlation coefficient (ICC) >0.9. Analysis of pinch strength measurements performed using the pinchmeter also found high values of the Pearson's correlation coefficient close to 1, as well as the interclass correlation coefficient >0.9; this reflects high agreement between the measurements performed by two investigators as well as assessments performed by one investigator at time intervals. These findings were confirmed by analyses performed using Bland-Altman plots. The measurements made with the Biometrics E-link EP9 evaluation system show high internal and external consistency in hand grip and pinch strength assessment. Biometrics E-link EP9 can be recommended for daily clinical practice. [ABSTRACT FROM AUTHOR]

The chemical industry is acquiring new advancement day by day. Previously, quite massive equipment had been used to do heat transferring tasks, but now the industry has been modernised. Heat Integration is a trending area of study that might be applied in several sectors to redesign processes. Heat Integration alludes to any technique in chemical engineering that results in considerably smaller, greener, and more energy-efficient appliances. Heat Integration aims to improve energy transfer, lowering the equipment's capacity for heat transfer. This paper uses pinch analysis to optimize heat integration and find the best heat-exchange network through case studies. Pinch Technology offers a systematic approach to reducing energy use across all sites and activities. It is feasible to determine the proper alterations to the fundamental process parameters that can result in energy savings by using pinch technology. The Aspen Energy Analyzer tool has been used to compute the heat integration of the case studies. After obtaining the data from the software, they were used in pinch analysis to determine the optimal alternative for the heat exchanger network. [ABSTRACT FROM AUTHOR]

The thermal energy transfer characteristics of heat exchangers with thermal fins and evaluates their economic feasibility. It uses computational fluid dynamics simulations and economic analyses to examine various fin geometries, materials, and configurations. The results reveal that fin design parameters, such as height, thickness, spacing, and material properties, significantly influence heat transfer efficiency. The study emphasizes the importance of optimizing these parameters to balance thermal performance and costeffectiveness. The findings guide engineers and policymakers in selecting and optimizing thermal fins. A range of water flow speeds of 0.1, 0.5, and 1 m/s was used, and the dimensions of the fins were reduced in a manner commensurate with the nature of thermal energy transfer and to reduce the manufacturing cost. The study shows that thermal energy transfer through fins increases with fluid flow speed, with the pipe's exit temperature reaching 88 degrees Celsius at 0.1 m/s and 96 degrees Celsius at 0.5 m/s. The fins' temperature distribution varies, reaching 88 degrees Celsius, 94 degrees Celsius due to fin length changes, and 91 degrees Celsius despite fin size changes. The study also analyzed energy transfer through different shapes and flow speeds, finding that shape 1 transferred 340 W at 1 m/s, shape 2 decreased to 144 W, and shape 3 increased surface area but not volume. [ABSTRACT FROM AUTHOR]

Balancing burgeoning energy demands in the electricity sector while curbing carbon emissions poses a formidable challenge for emerging economies like Bangladesh, which is heavily reliant on fossil fuels. Despite the country's power system master plan (PSMP) until 2041 and submitted intended nationally determined contributions (INDC) to tackle mounting energy needs and associated emissions, the PSMP lacks specific emission reduction strategies. Thus, this study employs carbon emission pinch analysis to facilitate Bangladesh's long-term energy planning, highlighting emission reduction hurdles. This research aims to set emission limits, delineate fossil fuel and carbon-neutral source (i.e., zero emission during operation) compositions, ascertain carbon-neutral source ranges for targeted emissions, and propose viable carbon-neutral sources to meet escalating energy demands. Three scenarios are extensively explored: fulfilling INDC mandates, a 10% increase in renewable energy, and maintaining 2035 emission levels in 2040. The analysis unveils emission limits of 55 758.83 and 84 778.61 × 109 grams of CO2 equivalent for 2025 and 2030, respectively. Projections indicate a foreseen 10% surge in renewable energy by 2035, elevating its share to 18.16%. Carbon-neutral energy sources, encompassing solar, wind, hydroelectricity, biomass, and nuclear, are estimated to cover 56.06% of energy demand by 2040, driving a 33.30% emissions reduction. [ABSTRACT FROM AUTHOR]

The reversible operation of a commercialized molten carbonate fuel cell as an electrolyzer is attractive to store the surplus of renewable energy and convert CO 2 into valuable fuel, like syngas (H 2 and CO). This work aims to assess this capability by developing a model for the co-electrolysis of CO 2 and H 2 O in the molten carbonate electrolysis cell (MCEC). Furthermore, a 1 MW power-to-gas system is simulated and optimized to maximize the process efficiency via a profound sensitivity analysis and a pinch heat integration analysis. The study's results reveal that when CO 2 electrolysis occurs, there is a risk of reaching the limiting current density at lower values, thus affecting the cell's performance. As for the simulation, the process yields an efficiency of 68.87% with an electrolyzer's power density of 0.082 W/cm2 per cell, producing 1.3 tons/day of methane gas ready for injection into the natural gas network. • Co-electrolysis of H 2 O and CO 2 in a molten carbonate electrolyzer was modelled. • 1 MW power-to-gas system is simulated and optimized via a sensitivity analysis. • Process yields an efficiency of 68.87% with 1.3 tons/day methane gas production. • The electrolyzer operates at a power density of 0.082 W/cm2 per cell. [ABSTRACT FROM AUTHOR]

In order to response to the “double carbon” strategy for reducing emissions, chemical production processes were optimized to lower the amount of utility work and equipment investment expenses with increasing the system’s capacity for heat recovery. A sensitivity analysis and the energy efficiency analysis with pinch technique were performed on the distillation and purification of the 30 kt/a isopropyl acetate (IPAC) production process by using process simulation software of Aspen Plus. The IPAC refining tower optimization results show that the purity of the refined IPAC could be reached 99.9% at circumstances of 44 theoretical plates, 19 feed plates, and 0.755 reflux ratio. According to the optimized energy consumption data from Aspen Energy Analyzer (AEA), the cold and heat logistics matching was performed. It can be seen that the heat exchange network was tuned to maximize energy recovery by reducing the amount of utility work. The optimized cold and heat utility usage were 734.69 and 727.81 kW, which meaning that compared with original process, the cold and heat utility usage energy can be save with 10.0%, respectively. The optimized results provide a certain theoretical basis and solution for improving energy saving and reducing investment costs. [ABSTRACT FROM AUTHOR]

Spray drying systems with heat recovery have gained prominence in recent times due to the energy crises and changing weather conditions. These systems are widely used in various industries, including chemical, food, fertilizer, and pharmaceutical, but their energy-intensive nature calls for efficient operation and heat retrieval. This review article discusses the current developments in heat recovery methods, including direct, indirect, and hybrid systems, as well as improvements in dryer efficiency and thermal optimization techniques. Pinch and exergy evaluations are extensively investigated as they play a crucial role in heat integration design and analysis. Recovering heat from the exhaust stream of spray dryers poses challenges due to fouling caused by fines in the exit stream and the selection of analysis methods. Exploring non-conventional energy sources like solar and geothermal energy shows potential for drying operations, but further research is needed for design and control. The adoption of recovery options has led to a 35% improvement in energy efficiency and around 74% energy savings in specific cases. [ABSTRACT FROM AUTHOR]

Trinidad and Tobago's (T&T) conditional commitment to the Paris Agreement requires an overall power emission avoidance (EAT) of 28.7 MtCO2-e from Business-As-Usual by 2030, dependent on international financing. T&T has outlined several initiatives to achieve this, including zero-carbon renewable energy (RE) introduction. However, other technologies such as Carbon Capture and Storage (CCS) can also be used in support of achieving EAT. Using a specific scenario (S3), this study assesses the techno-economics of CCS within the sector to minimize the requirement of RE using a carbon measuring tool called Carbon Emission Pinch Analysis (CEPA) to achieve EAT. Local power plants were screened, and a CCS retrofit was then technically designed using a validated software called Aspen HYSYS. Multi-period CEPA methodology was then applied to quantify ∼17% of grid energy from RE along with CCS to achieve EAT. Economic models were also used to determine the grid unit cost of emission abatement for S3 to be 64 USD/tCO2-e; a doubling of initial projection requirements. With T&T's current dynamics, these findings can help guide actions to reduce the requirements of RE onto the grid through the supplemental introduction of CCS to achieve its EAT. [ABSTRACT FROM AUTHOR]

• Energetic and exergetic analysis of a TC-HTHP cycle configurations. • Gas-cooler pinch point analysis of a TC-HTHP cycle. • Environmental impact of operating a TC-HTHP within an industrial process. • HC-600 (Butane) demonstrated the highest VHC values and, therefore, the smallest size of compressor. Sub-critical mechanically driven industrial heat pump technologies have gained momentum in recent years with systems capable of supplying temperatures up to 150°C. Extending the operating envelope using heat pump technologies to and beyond 200°C requires an innovative shift towards transcritical techniques to meet the demands of a broader range of industrial processes. Transcritical high-temperature heat pumps (TC-HTHPs) pose many technical and operational challenges requiring research and development to evaluate operational performance. This paper assesses the feasibility of operating a HTHP system to achieve 200°C heat sink temperatures using suitable low GWP refrigerants. The work investigates three different TC-HTHP cycle configurations using a steady-state theoretical model to compare and evaluate energetic, exergetic and environmental performance. In addition, cycle performances for this study are obtained at the optimum pressure for the gas cooler in which the maximum COPs are achieved. The results reveal that the basic cycle with dual internal heat exchanger (IHX) was the most efficient configuration, with HFO-514A and HFO-1234ze(Z) refrigerants identified as the most promising candidates for TC-HTHP systems. Configurations employing HCFO-1233zd(E) exhibited a trade-off between high energetic and exergetic efficiency while providing an A1 safety group classification. A pinch point analysis of the gas cooler demonstrated the need to optimise the overall length to achieve increased operational performance at very high glide temperatures. An evaluation of the environmental impact identified reductions in TEWI value by up to 20 % for the refrigerants tested over HFC-245fa. This study provides a basis for future practical activities of TC-HTHPs using eco-friendly candidates. [ABSTRACT FROM AUTHOR]

The effective utilization and conservation of energy are crucial challenges in industrial process systems. The chemical engineering industry is actively researching the integration of processes via heat exchanger networks synthesis. The strategy presented in this work utilizes recent advancements in pinch technology to investigate the impact of minimum approach temperature variation on energy and capital costs. The multi-objective problem considered in this approach involves minimizing utilities of heating and cooling, minimizing the area of heat exchanger, minimizing irreversibility, and maximizing effectiveness. The technique of order preferences by similarity to an ideal solution (TOPSIS) is applied to determine the optimal heat exchanger network based on the compromise solution concept, which is achieved by selecting the network having the closest Euclidean distance to the perfect solution. The practicality of this methodology is validated by resolving two distinct cases, the first case involve ten streams, the second industrial case is a separating crude oil into its primary constituents namely naphtha, kerosene, diesel and residue which demonstrate that this technique can provide more practical solutions compared to prior literature. Additionally, the study reveals that the novel approach can identify other multi criteria decision making problems with a discrete number of alternatives, criteria and are more cost-effective networks than those produced by alternative techniques. [ABSTRACT FROM AUTHOR]

It is important to estimate the energy required in ore processing to select the most affordable and efficient energy system for the integration of renewable resources into the mining industry. In the present work, the energy consumption for the concentrate of tungsten ore in Mongolia was theoretically predicted based on operational variations (particle size and the hardness of the tungsten ore) and different equipment. The energy was in the range from 0.48 to 1.32 kWh/t for the crushing stage, and a cone crusher was more suitable than a jaw crusher due to the particle size of feed material and product. The required energy in the grinding stage was from 6.22 to 11.88 kWh/t using a SAG mill or from 3.04 to 7.39 kWh/t using a ball mill. The further separation by a flotation consumed 4.83 kWh/t or by a shaking table consumed 1.29 kWh/t. The maximum energy consumption per hour for the whole process was estimated to be 2–3 MW, which was better to integrate with a hybrid renewable energy system. The sizing method Power Pinch Analysis was used to estimate the electric supply based on the combination of wind, biomass and solar resources, which was sufficient for the demand from the predicted range of energy. [ABSTRACT FROM AUTHOR]

Ventilation heat loss is one of the most important factors contributing to energy performance of greenhouses. This paper suggests a systematic method based on dynamic pinch analysis (PA) to design an integrated heating, cooling, and ventilation system that uses ventilation waste heat in a cost-effective and energy efficient way. A heat recovery system including an air handling unit, borehole thermal storage, and a heat pump is proposed to investigate all heat integration scenarios for an entire year. In the first step, the heat integration scenarios are reduced to a few typical days using a clustering technique. Then, a generic methodology for designing a heat exchanger network (HEN) for a dynamic system, ensuring both direct and indirect heat recovery, is presented and a set of HENs are designed according to the conditions of typical days. Afterwards, the best HEN design is selected among all design alternatives using a techno-economic analysis. The whole procedure is applied to a commercial greenhouse and the best HEN configuration and required equipment sizes are calculated. It is shown that the best-performing design for the greenhouse under study produces primary energy savings of 57%, resulting in the shortest payback period of 9.5 years among all design alternatives. [ABSTRACT FROM AUTHOR]

This paper studies the combined heating and cooling thermal performance of a CO2 heat pump system considering the subcooling effect. For such a system without cold thermal energy storage (CTES), the gas cooler outlet temperature normally needs to be controlled to match the cooling load required. However, the integration of CTES would enable the system to be operated under its optimal conditions depending on the ambient temperatures, i.e. a considerable amount of cooling capacity can be generated and stored for later use. A configuration of a CO2 heat pump integrated with CTES is described in this paper. A thermodynamic cycle and a simulation model considering the subcooling effect have been developed. The mathematical model for the pinch point analysis has been newly validated against published experimental data with acceptable agreements. In the case study, the impacts of the subcooling temperature on the optimal combined performance under four ambient temperatures (5 °C, 15 °C, 25 °C, and 32 °C) have been studied. The highest optimal combined COP of 5.38 can be achieved when the ambient temperature is 5 °C. The detailed profiles of CO2 temperatures, heating and cooling loads, and the COPs when the CTES is in operation have been revealed for the first time. It is found when the ambient temperature is higher than the water inlet temperature (plus the pinch point temperature), the optimal cooling COPs can even have a surge without the subcooling effect, due to a lower sCO2 temperature leaving the heat exchanger compared to the ambient temperature. Additionally, performance analysis for the CO2 heat pump system with or without CTES is compared, and it is concluded that all optimal heating, cooling, and combined COPs integrated with CTES surpass those without CTES. [ABSTRACT FROM AUTHOR]

The present paper proposes ways to reduce energy consumption during naphtha isomerization and catalytic reforming by optimizing the recovery heat exchange of the feed preparation unit using pinch analysis. A pinch analysis procedure based on heat flux integration was carried out in three stages. At the first stage, information on the technological and energy characteristics of the unit was collected and studied. At the second stage, options for improving the energy efficiency of the unit were determined. At the third stage, a detailed study of technical solutions for optimizing the flow scheme of recovery heat exchange was performed along with an economic justification. Proposed options for modernizing the existing industrial unit are based on the set of positive values for economic indicators and criteria of the program for improving the operational efficiency. The presented heat exchange system layouts can be used in the design and modernization of secondary naphtha distillation units at oil and gas refineries. [ABSTRACT FROM AUTHOR]

The development of technologies for utilizing biomass has attracted attention because biomass can be produced sustainably worldwide. Biomass‐derived 2‐methyltetrahydrofuran (MTHF), which is a promising alternative to gasoline, has great market potential and a growing demand. However, in conventional biomass conversion processes, the minimum selling price (MSP) of biochemicals is not economically acceptable. Co‐production of biochemicals can increase the economics of biomass utilization. Herein, we developed a process for co‐producing MTHF and 1,4‐pentanediol (1,4‐PDO) from lignocellulosic biomass. After biomass fractionation, cellulose and hemicellulose were converted to levulinic acid (LA), and lignin was used for heat and electricity generation. LA was then converted to γ‐valerolactone (GVL). As a platform material for co‐production, GVL was converted into MTHF and 1,4‐PDO in each subsystem. The split ratio of GVL was controlled to efficiently produce MTHF and 1,4‐PDO according to market conditions. Additionally, we performed a techno‐economic and life‐cycle assessment (TEA and LCA, respectively) for the developed process. The MSP of MTHF was calculated based on the TEA results, and the environmental impacts were quantitatively calculated based on the LCA results. We performed heat integration using pinch analysis and then reduced the energy requirement of the proposed process. The key cost drivers and environmental factors of the proposed process were identified via sensitivity analyses. Consequently, during the processing of 2000 ton/day of corn stover (raw material of lignocellulose), the MSP of MTHF was calculated as $2.64/GGE (gasoline equivalent), and representative environmental impacts such as climate change and fossil depletion were calculated as −0.296 kg CO2 eq and − 0.056 kg oil eq, respectively. As a result, we can increase the economics of commercial production of MTHF and 1,4‐PDO with environmental sustainability. The proposed process can serve as a potential solution to the growing demand for the need for more sustainable biomass utilization. [ABSTRACT FROM AUTHOR]

It is important to properly account for the emissions contribution of process units in order to develop cost-effective industrial decarbonization strategies. However, there is limited literature on this topic in the edible oil refining sector. This work addresses this research gap by developing a novel systematic technique for assessing decarbonization options in the palm oil refining process. This technique combines enterprise input-output analysis (EIOA) with graphical carbon emission pinch analysis (CEPA) into a unified approach to examining cost-effective decarbonization measures. Results show that the average carbon intensity of the system was 0.0432 kg CO 2 /$ while the total carbon footprint was 2339.97 kg CO 2. Palm fatty acid distillate (PFAD) has the highest carbon intensity contribution (0.0392 kg CO 2 /$) among the multiple products. Four scenarios to achieve a 20% reduction in CO 2 emissions based on heat integration and process changes were examined. Economic evaluation was also conducted for each proposed strategy. • An integrated EIO-CEPA technique was developed for industrial decarbonization. • The technique was applied on a palm oil refining process. • Carbon intensity reduction of 20% was set as a benchmark. • Four decarbonisation scenarios were analysed along with their economic feasibility. [ABSTRACT FROM AUTHOR]

The evaporation station is at the center of the energy balance of sugar mills. The objective was to propose a methodology for the energy evaluation of the evaporation station that complements the methods for energy management in sugar mills; in correspondence with the energy management system (EnMS) based on the ISO 50001 standard and its complementary standards. The methodology was structured according to the PDCA cycle of Continuous Improvement (Plan-Do-Check-Act), a recurrent process to improve energy performance. The methodology takes into account the contributions and overcomes limitations of existing methodologies. It incorporates methods and criteria for developing an energy review; considers the impact of evaporation station design, construction and operation on energy efficiency; and emphasises the synergy between the methods of energy analysis, exergy analysis, process integration (Pinch Analysis). It constitutes a methodological contribution that strengthens the energy review of the evaporation station, allowing the exhaustive analysis of the problem and the relevance of improvements to increase energy efficiency; and complements existing methods for energy management in sugar mills. [ABSTRACT FROM AUTHOR]

Microalgae are the third generation of biomasses that have received lots of attention due to their high energy content and ability to capture carbon dioxide from the air. However, there are some techno-economic challenges for their world commercialization. A variety of fuels can be extracted from microalgae, and in addition to these fuels, algae by-products can be used to commercialize this industry. Various processes will be performed on microalgae to finally desired products can be extracted. In this research, an integrated system has been designed for the simultaneous production of ethanol, methane, and hydrogen from Chlorella vulgaris microalgae. The results showed that after culturing, harvesting, and increasing the concentration of the solution in addition to the main products such as ethanol, methane, and hydrogen, by-products including acetic acid, methyl acetate, ethyl acetate, furfural and etc. can be utilized for commercializing microalgae industry. Also, another purpose of this study is to apply Pinch Analysis to the mentioned system, which will ultimately improve the concentration of microalgae in the photobioreactor. The results of Pinch Analysis show that by increasing the concentrations of microalgae, carbon dioxide, and nutrients in the photobioreactor inlet up to 2.35 gr/l, the desired amount of demands can be met by the new supplies. [Display omitted] • Designing a simultaneous production process of ethanol, methane and hydrogen. • Modifying the production of biofuels and value-added materials from the microalgae. • Doing mass balance analysis, energy balance analysis and mass pinch analysis. [ABSTRACT FROM AUTHOR]

The development of process flow diagrams requires knowledge of reaction enthalpy for pinch analysis and thermal risk assessment. Such information is missing for some biomass processes, such as the production of γ-valerolactone (GVL) from the hydrogenation of levulinic acid or alkyl levulinate. To fill this gap, this manuscript describes a detailed calorimetric study on the hydrogenation of levulinic acid (LA), methyl levulinate (ML), ethyl levulinate (EL), propyl levulinate (PrL), butyl levulinate (BL) and pentyl levulinate (PeL) over Ru/C. This reaction system occurs through a two-step pathway with a domino hydrogenation/cyclization sequence. The cyclization step (lactonization) was found to be endothermic and was evaluated by a Tian-Calvet C80 micro-calorimeter, whereas the hydrogenation step was found to be exothermic and was tracked by a RC1 Mettler Toledo High-Pressure calorimeter. It was verified that reaction enthalpy is independent of reaction temperature (in the operating conditions used in this work), levulinate concentration and solvent (levulinate, corresponding alcohol or GVL). It was also found that reaction enthalpy for both steps did not depend linearly on alkyl chain length. [Display omitted] • Hydrogenation enthalpy for alkyl levulinates was determined. • Cyclization enthalpy for alkyl 4-hydroxypentanoate was obtained. • Reaction enthalpies for hydrogenation of alkyl levulinates are independent of operating conditions. • No linear correlation between alkyl chain length and reaction enthalpy was observed. [ABSTRACT FROM AUTHOR]

Uncertainties are widely present in the design and simulation of aero-engine combustion systems. Common non-probabilistic convex models are only capable of processing independent or correlated uncertainty variables, while conventional precise probabilistic sensitivity analysis based on ideal conditions also fails due to the presence of uncertainties. Given the above-described problem, an imprecise p-box sensitivity analysis method is proposed in this study in accordance with a multi-dimensional parallelepiped model, comprising independent and correlated variables in a unified framework to effectively address complex hybrid uncertainty problems where the two variables co-exist. The concepts of the correlation angle and correlation coefficient of any two parameters are defined. A multi-dimensional parallelepiped model is built as the uncertainty domain based on the marginal intervals and correlation characteristics of all parameters. The correlated variables in the initial parameter space are converted into independent variables in the affine space by introducing an affine coordinate system. Significant and minor variables are filtered out through imprecise sensitivity analysis using pinching methods based on p-box characterization. The feasibility and accuracy of the method are verified based on the analysis of the numerical example and the outlet temperature distribution factor. As indicated by the results, the coupling between the variables can be significantly characterized using a multi-dimensional parallelepiped model, and a notable difference exists in the sensitivity ranking compared with considering only the independence of the variables, in which input parameters (e.g., inlet and outlet pressure, density, and reference flow rate) are highly sensitive to changes in the outlet temperature distribution factor. Furthermore, the structural parameters of the flame cylinder exert a secondary effect. [ABSTRACT FROM AUTHOR]

The proton-conducting solid oxide electrolysis cell (H-SOEC) is a clean technology for syngas production from H 2 O and CO 2 through electrochemical and chemical reactions. However, it provides a low CO 2 conversion and produces a syngas product with a high H 2 O content. To improve the H-SOEC for syngas production, H-SOEC coupled with a dry methane reforming process (H-SOEC/DMR) was proposed in this work. The process flowsheet of the H-SOEC/DMR was developed and further used to evaluate the performance of the H-SOEC/DMR process. From the performance analysis of the H-SOEC/DMR process, it was found that the CO 2 and CH 4 conversions were higher than 90% and 80%, respectively, when the process was operated in the temperature range of 1073–1273 K. In addition, the result showed that a syngas product with a low H 2 O content could be obtained. Energy efficiency was then considered and the results indicated that the highest energy efficiency of 72.80% could be achieved when the H-SOEC/DMR process was operated at a temperature of 1123 K, pressure of 1 atm, and current density of 2500 A m−2. Based on a pinch analysis, a heat exchanger network was applied to the H-SOEC/DMR process that improved the energy efficiency to 81.46%. Finally, an exergy analysis was performed and showed that the H-SOEC/DMR unit had the lowest exergy efficiency as a high-temperature exhaust gas was released. [Display omitted] • The syngas production from H-SOEC is improved by incorporating with DMR. • The obtained syngas product has a high H/C molar ratio of 2 with less amount of H 2 O. • Increasing temperature can reduce the cell voltage and enhance syngas product. • The implementation of heat exchanger network can enhance the energy efficiency to 81.46%. [ABSTRACT FROM AUTHOR]

• Light gas separation unit of MTP process and refrigeration cycles are simulated. • A new multi-objective optimization approach for minimizing TAC with achieving to the desired product specifications is applied. • Pinch and exergy methods are used for obtaining optimal results in columns and refrigeration cycles operating conditions. • Real costs of refrigeration cycles considering of their interactions with separation columns are calculated. • Operating parameter of the propylene and ethylene refrigeration cycles are optimized simultaneously with distillation columns. In this study, optimization and economic analysis of the separation of light gases in the methanol to propylene, MTP, process along with refrigeration cycles design are performed, by using pinch and exergy analysis. In the course of the separation process optimization and refrigeration cycles design, by using a Visual Basic, VB, program and genetic algorithm, GA, rigorous distillation simulation is carried out, then streams information is employed to find optimum temperature levels, corresponding to tower condenser temperature, by minimizing the areas between the Exergy Grand Composite Curve, EGCC, and constant temperature levels of refrigeration cycles. Economic calculations were performed to obtain the lowest total annual cost, TAC, for refrigeration cycles, towers and other equipment. Two cases of the direct and indirect sequences are examined through the developed framework, inspection of their results represents that the operational cost has a significant contribution to the TAC. As a result, heat integration would reduce it by nearly 60%. Also, scrutinized analysis of the optimization results, especially by considering the TAC and its contributions, for the direct and indirect sequences, leads to the conclusion that indirect sequence would exhibit lower cost for light gas separation. The framework represented herein paves a way to the systematic design of integrated low-temperature separation processes with refrigeration cycles. [ABSTRACT FROM AUTHOR]

In view of the characteristics of the water-methyl acetate-tetrahydrofuran ternary azeotropic system, a heat integrated extractive distillation process was proposed to study its separation. The WILSON thermodynamic model was selected to calculate the vapor-liquid equilibrium data of the system, and the two-phase flash module in ASPEN PLUS software was used to simulate the relative volatility between the azeotropic components for the system under different extractant conditions. The results showed that ethylene glycol was more suitable as the extractant for the system, and the best solvent ratio was 0.37. On this basis, taking energy consumption and annual total cost (CAT) as technical and economic evaluation indicators, the conventional three-column extractive distillation process was simulated and the parameters were optimized, and the heat exchange network of the distillation system was optimized by using pinch point analysis technology. Based on the optimized results of the heat exchange network, the conventional three-column extractive distillation process was integrated with heat. The research results showed that compared with the conventional three-column extractive distillation process, the heat integrated extractive distillation process can reduce energy consumption by about 34.70%,save CAT about 21.98%,and increase thermodynamic efficiency by 36.34%.Therefore, the heat integrated extractive distillation process is a more suitable energy-saving process route for separating the ternary azeotrope system. [ABSTRACT FROM AUTHOR]

Heat recovery is considered as the key to improve energy efficiency in the process design. An appropriate heat exchanger network (HEN) design is an effective tool to maximize heat recovery from the process streams and to minimize energy consumption. The objectives of this study were arranging optimum HEN based on the annual cost in the power industry. HEN in the Paiton Steam Power Plant, East Java, Indonesia, was designed using spreadsheet and Aspen Energy Analyzer with Peng-Robinson equation. Pinch analysis was conducted by comparing Tmin (10°C - 19°C) to obtain Maximum Energy Recovery (MER) and Heat Exchanger Area (HEA). The HEN design was optimized using grid diagram. Simulation in this study succeeded to reduce the annual cost the most effectively at ΔTmin 16°C. This design optimized the process integration and contributed to the capital, operation, and total annual cost reduction of 14.3%. The maximum energy recovery was 286,706 kW and HEA 138.790 m². This result is a solution for Steam Power Plant as an effort for enhancing energy efficiency and the company competitiveness. [ABSTRACT FROM AUTHOR]

Energy integration is a critical solution for crude oil distillation units to reduce fuel consumption and environmental impacts. There are several proposed innovations for the networks of the heat exchanger, in addition to optimising operations in recent decades, for the purpose of enhancing the energy and economic efficiencies of the system of distillation of crude oil. However, retrofitting is often constrained by the constraints of maintenance, safety, and the topology of the process, but revamping managers prefer to exploit the existing equipment. Retrofit aims to reuse the existing equipment more efficiently to achieve various objectives, such as reducing utility consumption and minimising CO2 emissions. This study introduces an optimal operation modification for the purpose of enhancing the energy savings of the existing unit of crude oil distillation. First, a detailed process operation is explained, simulated, and analysed with ASPEN HYSYS software, and then two modifications are proposed. The proposed modifications aim to achieve higher energy savings while retaining the economic gain than conventional approaches and without any additional investment in a retrofit in an industrial case, especially up to 28% of the reduction of energy. It is also equivalent to a 23.38% reduction of CO2 emissions every year. [ABSTRACT FROM AUTHOR]

Trinidad and Tobago (T&T) aims to reduce the Business-As-Usual (BAU) emissions in its power generation sector by 28.7 MtCO2-e by 2030 according to its National Determined Contribution (NDC). Based on current published data, there appears to be a gap in quantifying the activity level and carbon intensity of planned actions to meet this target. Through two scenarios, this study explored the impacts of power plant dispatch optimization and new zero-carbon energy additions for T&T through adaptations of a widely used method called Carbon Emission Pinch Analysis (CEPA). A national grid emission factor (GEF) of 0.56 MtCO2-e/TWh was determined using an internationally accepted methodology from gathered power plant data. The GEF was discretized to project a BAU case to benchmark both scenarios. Scenario 1 (S1) determined T&T would achieve 8% of the NDC target if the existing supply is optimized in the years 2022 to 2030 through the compound pinch points. To achieve the target, Scenario 2 (S2) determined that at least 47% of T&T's grid energy needs to come from zero-emission carbon sources by 2022. This would equate to required capacities of 2,169 MW of solar photovoltaic or 1,549 MW of onshore wind using the most recent published capacity factors, and a decrease in the BAU GEF by 43%. [ABSTRACT FROM AUTHOR]

Integrated energy–water systems have been explored using different process integration techniques considering the energy–water–carbon nexus to minimize the carbon footprint, e.g., pinch analysis techniques (power cascade table, water cascade table, and energy planning pinch diagram). However, the power and water losses while considering the energy–water–carbon nexus have not been explored in detail in the previous works. This work focuses on the modifications of the existing pinch analysis methods for energy–water–carbon nexus study while considering power and water losses, for an optimized energy–water system. Power and water losses should not be neglected in the analysis as they have a significant impact on the carbon emissions and overall capacities of energy and water. The effect of losses on energy storage capacity, outsourced electricity, water supply volume and water storage capacity were evaluated on an industrial case study. Results from the case study demonstrate that, while considering power losses during power allocation can lower storage capacity, it tends to raise the needed outsourced electricity supply. As water supply volume tends to increase, the water storage capacity tends to decline when losses are considered. The results were compared to the data without losses, and it was observed that the storage capacity of energy decreases by 4% while outsourced energy increases by 6%. Water supply volume increases by 20% but water storage capacity decreases by 13.7%. The emissions from energy system remains same while from the water system the emissions rise significantly by 20%. It is expected that consumers that takes power and water losses into account will produce more realistic and reliable energy, water, and carbon reduction targets and prevent under-sizing issues in designing integrated energy–water systems. [ABSTRACT FROM AUTHOR]

The present paper reviews 47 Life Cycle Assessments (LCA) applied to chemical reactions. The selection of the evaluated articles was conducted with a systematic literature review methodology. The review arises from the need to define the best methods for developing LCAs of chemical processes at industrial scale. The authors go through the stages defined in ISO 14040 and 14044, identifying both the gaps and the best techniques used in all the reviewed papers. The main difficulty observed when developing LCAs of chemical reactions is the lack of data due to confidentiality issues in chemical companies. In addition, this data is commonly only available at the laboratory scale. Laboratory data is sometimes directly upscaled without further consideration. Even though, simulation software, advanced calculations benchmarks, pinch analysis and retrosynthetic analysis are the best methods to estimate and scale up the mass and energy balances in the Life Cycle Inventory (LCI) stage. The article discusses these upscale procedures, makes a deep analysis of each single LCA stage, and assesses how chemical process information is managed, which is a novelty regarding previous reviews of chemical reaction LCA. From the Life Cycle Impact Assessment (LCIA) methodologies, they should be standardized to enable the comparability between LCAs of the same product. Both the European Commission and the Life Cycle Initiative are making progress in this regard. Eventually, the ReCiPe is the most used methodology among the reviewed papers. Finally, the article proposes different analyses to be performed in the interpretation phase: i.e., projecting the energy mix foreseen for the years 2030 and 2050 in energy-intensive processes or including other sustainability vectors (economic and social) in cross-cutting projects. [ABSTRACT FROM AUTHOR]

This paper presents a novel systemic algorithm based on conservative power pinch analysis principles using a computationally efficient insight-based binary linear programming optimization technique in a model predictive framework for integrated load shifting and shedding in an isolated hybrid energy storage system. In a receding 24-hour predictive horizon, the energy demand and supply are integrated via an adaptive power grand composite curve tool to form a diagonal matrix of predicted hourly minimum and maximum energy constraints. The intgrated energy constraints must be satisfied recursively by the binary optimisation to ensure the energy storage's state of charge only operates within 30% and 90%. Hence, the control command to shift or shed load is contingent on the energy storage state of the charge violating the operating constraints. The controllable load demand is shifted and/or shed to prevent any violations while ensuring energy supply to the most critical load without sacrificing the consumers' comfort. The proposed approach enhances efficient energy use from renewable energy supply as well as limits the use of the Hydrogen resources by a fuel cell to satisfy controllable load demands which can be shifted to periods in the day with excess renewable energy supply. [ABSTRACT FROM AUTHOR]

Studying industries energy saving is very important prospect for many researchers in the last four decades. In this respect, better process heat transfer can be achieved to improve process operating and capital cost. Thereafter, obtaining higher amount of heat recovery, which will help to reach system optimum heat exchanger network design. Application of Pinch analysis (PA) in our current study, was found to be as an effective method towards economic solution and assessment for all system thermal processes. Whereby, minimizing energy losses, and thus, prediction of maximum energy saving. In addition, application of "Aspen Energy Analyzer (AEA)" simulation software assist our effort to optimize Heat Exchanger Network design (HEN), with various application scenario towards best design. This study represents a "Case study" as a Brayton closed cycle gas turbine power plant in Al-khairat district, which is one of a number of sites used to generate electricity for Iraq national grid. However, the plant original design is open cycle. This study, represent an attempt to apply (PA) in system closed cycle model with the same working conditions. The results predicted, on the contrary of open cycle, that using closed cycle (PA) with temperature difference ΔTmin can be acceptable with several design propositions. The optimum (ΔTmin = 15℃) were evaluated in the closed cycle system pinch analysis, thereby the maximum Qrec. process that minimize the QHmin & QCmin requirement were identified by the software simulation for the best HEN design. These results were found as Qrec. = 318.330 MW, QHmin = 88.607 MW and QCmin =39.564 MW. [ABSTRACT FROM AUTHOR]

Process Integration combine several processes to reduce consumption of resources and harmful emissions, becoming an important asset in ensuring the sustainability of industrial processes. This paper aims to set energy performance indicators of a cane sugar refinery. A procedure that includes the energy analysis and Pinch Analysis methodologies is applied, with the use of HENSAD. Targets and energy performance indicators, currently not reported for this refinery, contribute to the definition of an energy baseline and the systematic measurement of efficiency. There is an excess in thermal power duty of 32,5 MW with respect to the minimum heating duty, which determines the research into retrofit designs of the heat exchanger network. Annual savings of 1 010 571 USD estimated in energy analysis and heat integration make the evaluation of investment projects in the energy area feasible. [ABSTRACT FROM AUTHOR]

This paper deals with the emission reduction in synthesis-gas production by better integration and increasing the energy efficiency of a high-temperature co-electrolysis unit combined with the Fischer-Tropsch process. The investigated process utilises the by-product of Fischer-Tropsch, as an energy source and carbon dioxide as a feedstock for synthesis gas production. The proposed approach is based on adjusting process streams temperatures with the further synthesis of a new heat exchangers network and optimisation of the utility system. The potential of secondary energy resources was determined using plus/minus principles and simulation of a high-temperature co-electrolysis unit. The proposed technique maximises the economic and environmental benefits of inter-unit integration. Two scenarios were considered for sharing the high-temperature co-electrolysis and the Fischer-Tropsch process. In the first scenario, by-products from the Fischer-Tropsch process were used as fuel for a high-temperature co-electrolysis. Optimisation of secondary energy sources and the synthesis of a new heat exchanger network reduce fuel consumption by 47% and electricity by 11%. An additional environmental benefit is reflected in emission reduction by 25,145 tCO 2 /y. The second scenario uses fossil fuel as a primary energy source. The new exchanger network for the high-temperature co-electrolysis was built for different energy sources. The use of natural gas resulted in total annual costs of the heat exchanger network to 1,388,034 USD/y, which is 1%, 14%, 116% less than for coal, fuel oil and LPG, respectively. The use of natural gas as a fuel has the lowest carbon footprint of 7288 tCO 2 /y. On the other hand, coal as an energy source has commensurable economic indicators that produce 2 times more CO 2 , which can be used as a feedstock for a high-temperature co-electrolysis. This work shows how in-depth preliminary analysis can optimise the use of primary and secondary energy resources during inter-plant integration. [Display omitted] • Transition to sustainable energy and share of high hydrogen-containing fuels. • Inter-plant integration via by-products recycling and better heat recovery was proposed. • Methodology combined process integration and process modification principles. • Unified process flow diagram for different fuel types was developed. • In-depth integrated syngas production consumes 47% less energy and saves 25,145 tCO 2 /y. [ABSTRACT FROM AUTHOR]

Sustainable energy systems are crucial for reducing carbon emissions because renewable energy sources leave a footprint. The petrochemical industry often suffers from inefficient heat exchange network (HEN) systems, leading to substantial energy wastage. In the current work, a real case study of the residue hydrogenation process was analyzed to identify potential energy savings. A new method combining Pinch Analysis and T hot –T cold diagram analysis methods was proposed. This graphical analysis method plots the cold-flow temperature of each heat exchanger unit on the x-axis and the hot-flow temperature on the y-axis. By applying the T hot –T cold diagram to a practical case of residue hydrogenation in Zhejiang, the existing process energy state was evaluated, and HEN was retrofitted to achieve energy savings and carbon emission reduction. Following optimization, the energy recovery amounted to 202.71 GJ/h with an energy recovery rate of 14.3 %. The proposed method saves approximately 4.058 × 105 GJ/y compared to current operations, resulting in an annual cost saving of approximately $ 2.76 M/y, with an investment payback period of less than 0.36 y. This study offers a solution to the energy challenges of industrial residue hydrogenation by enhancing the economic and environmental sustainability of existing process flows. • Case data of a real factory's heat exchanger network are studied. • New method combining pinch analysis and T hot –T cold diagram analysis methods. • Optimized energy-saving retrofit plan for an actual industrial process. • Energy savings of 4.058 × 105 GJ every year using the proposed process. • The payback period is 0.36 y. [ABSTRACT FROM AUTHOR]

The conventional methodology of heat pump integration has found application in various industries, including cheese production, spray drying, milk evaporation systems, brewing, and meat processing. While several approaches have been developed for optimizing direct and indirect heat recovery in non-continuous industrial processes, the optimal integration of heat pumps in non-continuous processes remains a challenge. This paper introduces a systematic methodology that leverages extensive datasets of time-resolved industrial process data to determine the optimal heat pump integration and the level of heat pump load flexibility that maximizes the economic benefit. Thus, the work establishes a connection between the domain of Process Integration and heat pump load flexibility. Additionally, the study provides insights on the requirements for load flexibility during the design phase of the heat pump, offering an estimation on the need for research on heat pump flexibility. The findings indicate the presence of a load flexibility threshold in the examined case study, beyond which additional load flexibility yields diminishing returns. Furthermore, the study shows that different heat pump integration parameters are chosen based on the heat pump's capability for load flexibility. Within the investigated case, a heat pump with a minimum load of 55% increases the net present value by 19.3% compared to a load inflexible heat pump. • Industrial heat pump integration for non-continuous processes. • Dynamic Pinch Analysis. • Reduced order heat pump part load model. • Techno-economic optimization for industrial heat pump integration and load flexibility. • Large time-resolved industrial process data. [ABSTRACT FROM AUTHOR]

Decarbonizing industrial processes is crucial for achieving net-zero targets, with process heat electrification emerging as a key pathway. Heat pumps (HPs) are pivotal for this transition. This study introduces a novel methodology to construct exemplar profiles for specific energy demands, representative profiles for various production capacities, and energy demand profiles at product, subsector, or sector levels, using Swiss chocolate production as a case study. Exemplar profiles offer flexibility in generating representative profiles based on production capacities, aiding in identifying integration opportunities and sizes for HPs. Sector-wide profiles provide a broader perspective, aiding in visualizing bottom-up sector-wide potential for HPs. Based on the analysis of four representative profiles for Swiss chocolate production, two potential standard heat pump (SHP) and three high-temperature heat pump (HTHP) integration opportunities were identified. Techno-economic data from 30 commercially available HPs were collected, assessing their cost-effectiveness for Swiss chocolate manufacturing using the levelized cost of saved energy and CO 2 abatement. Factors such as company size and electricity and natural gas prices impact the cost-effectiveness of HP integration. Despite variations, HPs with real coefficients of performance above 2.6 generally prove cost-effective for average energy prices and current CO 2 levies in Swiss chocolate production. Bottom-up estimations of HP integration potentials using product-specific energy demand profiles suggest a potential reduction of CO 2 emissions by up to 56% and an improvement in energy efficiency by up to 28% in Swiss chocolate production. • Bottom-up sectorial profiles are used to identify HP integration potential. • HP integration can potentially achieve up to 56% CO 2 abatement. • HP integration can potentially achieve up to 28% reduction in energy demand. • All HPs with COP greater than 2.6 are cost-effective except for very small companies. [ABSTRACT FROM AUTHOR]

• A scheme for mechanical pressurisation of reaction products followed by partial condensation in a thermally coupled manner is proposed. • A scheme for the evaporation of MCP from the top of the column was proposed for the discharge of impurities. • The heat transfer network of the whole process was optimised using pinch point analysis technique. • Processes with different feed concentrations of acetaldehyde were investigated. As an essential raw material of chemical industry, crotonaldehyde is mainly used to produce sorbic acid, which is a kind of safe food preservative. The nowadays production process of crotonaldehyde adopts sodium hydroxide solution and acetic acid in series as catalysis, which cause serious problems such as salinity waste water and equipment corrosion. Therefore, Zr-β zeolite was developed to catalyze the production of crotonaldehyde from acetaldehyde gas–solid reaction process in our group. This catalyst showed the potential of industrial application for its 94 % selectivity and stability. This paper aims to develop a technological process to produce crotonaldehyde from acetaldehyde based on the newely-researched-out Zr-β zeolite catalyst. According to experimental results of reaction condition and product distribution, a technological process consisting of (1) aldol condensation reaction and raw material recovery section, (2) crotonaldehyde concentration and refinement section, (3) 2-methyl-2-cyclopenten-1-one (MCP) and acidic impurity removal section was established. Mechanical supercharging was employed in section (1) to elevate the heat grade of reactor effluent to heat the reactor feed. Pre-concentration followed by azeotropic distillation was proposed to purify croton aldehyde product. The removal of little MCP in the re-used water was accomplished by evaporating MCP at the top of the column based on our previous finding that MCP-water could form minimum azeotrope. As a result, the purity of crotonaldehyde reached 99.92 wt% and water content reduced below 10 ppm in product, which is much better than the product standard required crotonaldehyde purity 99.5 % and water content 2000 ppm. Based on optimum process, heat exchange network was further optimized with pitch point method, and at last the required heat load was 2.25 Gcal per ton of crotonaldehyde product. The problem of generating salinity waste water in the traditional process was solved thoroughly, which meant that this is a more environmentally friendly process to produce crotonaldehyde. [ABSTRACT FROM AUTHOR]

The article describes and proposes practical use of pinch analysis as one of the methods for optimizing energy consumption at industrial plants. This method allows efficient distribution and utilization of energy flows in technological plants. Pinch analysis of recuperative heat exchangers in heavy resid deasphalting plants is discussed. Solvent deasphalting is one of the most energy-consuming oil refining processes, and primarily energy consumption determines the ultimate cost of deasphalted products, which are a feedstock either for catalytic cracking and hydrocracking plants or a component of lube oil production. Therefore, one of the means of enhancing energy efficiency of these plants is optimization of heat exchanger operation by pinch analysis. [ABSTRACT FROM AUTHOR]

Heat integration of oil refining processes is an effective instrument in the technological modernization of industrial facilities. A more rational use of the heat carried by internal process streams is of particular importance for such energy-intensive technologies of heavy oil residue cracking as delayed coking. In this work, we construct a model of the existing heat exchange network of a petcoke production unit and analyze it using pinch analysis. The conducted study revealed violations of the basic pinch principles committed when designing the existing network. An approach to enhancing the energy efficiency of the process was proposed, involving retrofitting of the existing equipment without expanding the heat exchange surface. [ABSTRACT FROM AUTHOR]

The tobacco industry is an important contributor to realizing the carbon reduction goal. Less attention is paid to the carbon emissions of the tobacco industry. The tobacco production system is generally a carbon sink, where carbon sequestration by photosynthesis in tobacco planting and by soil are sufficient to offset the carbon emissions of the tobacco production system. This work proposed an integrated framework of life-cycle assessment (LCA) and Source-Sink Model to determine the optimal allocation of carbon sources to sinks with the objective of maximizing the profitable external benefits. From an economic perspective, internal carbon sources could be offset by the internal carbon sink of the tobacco production system. The additional internal carbon sinks can be transferred in the form of carbon trading, increasing external revenue. A case-study tobacco manufacturing plant in Sichuan, China, was chosen to demonstrate the feasibility of the proposed work. This study assesses the carbon footprint and economic benefits of a tobacco industry supply chain case (from tobacco cultivation to finished product) and analyzes the energy restructuring of different percentages of renewable energy to replace thermal power. The objective of the study is to maximise the offsetting of carbon emissions from the tobacco production system, while achieving optimal internal costs and profitable external benefits. [ABSTRACT FROM AUTHOR]

Heat integration by pinch method is used to modify the heat exchanger network of an industrial ethylene glycol plant. The aim is to reduce the energy cost by operating the plant close to the maximum energy recovery. Pinch analysis identified a pinch temperature of 483 K, a minimum heating utility of 13,490.9 MJ/ton EO, and a minimum cooling utility of 25,697 MJ/ton EO. Using the pinch decomposition diagram and the standard procedure for matching hot and cold streams, a retrofit of the heat exchangers network is developed. The modified heat exchanger network reduces the external cooling duty by 45.5% and the external heating duty by 93.3%. This promising cost savings provide enough justification for restructuring the existing ethylene glycol plant. Moreover, an additional 6% reduction in the external cooling duty can be achieved by integrating the steam turbine below the pinch point. [ABSTRACT FROM AUTHOR]

An emphasis on sustainable growth helps decrease the initial capital and reduce the impact of industry on an ecologically sensitive environment through resource conservation. Pinch Analysis serves as a valuable tool to identify the potential for resource conservation, waste minimization, and resource costs. However, there are inherent uncertainties associated with these resource conservation networks. The concept of Pinch Analysis is broadened to multi-objective resource conservation problems incorporating parametric uncertainties in this paper. The objective functions are combined to form a single compound objective function using the weighted sum approach. For the compound objective function, prioritized sequences (or resource combinations) are generated through multi-objective prioritized costs to accommodate parametric uncertainties. The multi-objective prioritized cost vs. weights curve helps determine the unique prioritized sequences for different range of weights to achieve optimal solutions. An exact analytical expression for the maximum number of prioritized sequences is also derived. Furthermore, a method is presented to construct the complete Pareto-optimal front to represent all optimal solutions graphically. Two illustrative examples, the hydrogen conservation problem with two objectives (cost and emission) and the water conservation problem with three objectives (cost, land requirement, and emission), demonstrate the proposed method's utility and efficacy. A multi-objective resource conservation problem under normally distributed parametric uncertainties. [Display omitted] • Included parametric uncertainties in multi-objective resource conservation problems. • Stochastic Pinch Analysis minimizes multiple objectives with multiple resources. • Determined the maximum number of possible prioritized sequences of resources. • Proposed multi-objective prioritized cost to determine the optimal sequence. • Determined Pareto-optimal fronts to represent all the efficient solutions. [ABSTRACT FROM AUTHOR]

This paper proposes a methodology for efficient, accurate, and sustainable waste heat recovery, where the energy needs of an industrial plant allow the installation of thermal engines. In this methodology, pinch analysis, mathematical equations, machine learning models, and an optimization algorithm are combined for the first time. To satisfy the industrial requirements, the selected thermal engines are the steam Rankine cycle, the organic Rankine cycle, and the absorption refrigeration cycle, which are modeled by using multilayer perceptron neural networks. The Non-dominated Sorting Genetic Algorithm-III is used to solve the optimization problem. Moreover, multi-objective trade-offs between economic, environmental, and social aspects are studied. A case study is presented to show the applicability of the proposed methodology. The multilayer perceptron models of the thermal engines were created with high accuracy. Furthermore, the results show that with this methodology it is possible to find the optimal operating conditions of thermal engines and solutions that allow the use of different fuels to fulfill the three objective functions. [Display omitted] • A novel approach to waste heat recovery is presented. • Multilayer perceptron neural networks have been incorporated to model thermal engines. • Multi-objective optimization incorporating economic, environmental, and social aspects. • The multilayer perceptron models are created with high accuracy. • The optimal operating conditions of thermal engines are determined. [ABSTRACT FROM AUTHOR]

Reactive dyeing is primarily used in the textile industry to achieve a high level of productivity for high-quality products. This method requires heating a large amount of freshwater for dyeing and cooling for the biological treatment of discharged wastewater. If the heat of the wastewater discharged from the textile industry is recovered, energy used for heating freshwater and cooling wastewater can be significantly reduced. However, the energy efficiency of this industry remains low, owing to the limited use of waste heat. Hence, this study suggested a cost-optimal heat exchanger network (HEN) in a heat pump-assisted textile industry wastewater heat recovery system with maximizing energy efficiency simultaneously. A novel two-step approach was suggested to develop the optimal HEN in heat pump-assisted textile industry wastewater heat recovery system. In the first step, the system was designed to integrate the heat exchanger and heat pump to recover waste heat effectively. In the second step, the HEN in the newly developed system was retrofitted using super-targeted pinch analysis to minimize cost and maximize energy efficiency simultaneously. As a result, the proposed wastewater heat recovery system reduced the total annualized cost by up to 43.07% as compared to the conventional textile industry lacking a wastewater heat recovery system. These findings may facilitate economic and environmental improvements in the textile industry. [ABSTRACT FROM AUTHOR]

Municipal solid waste (MSW) is a persistent burden in many countries. The heterogeneous MSW characteristic requires a transition from the monotonous treatment strategy to a diversified low-carbon waste treatment configuration. Nevertheless, complex mathematical models hinder the policymakers from adopting scientific-based solutions in the decision-making process, and those models seldom link national greenhouse gas reduction targets to local waste policy targets. This study applies two approaches in constructing Carbon Emission Pinch Analysis to either optimize waste treatment system configurations while considering greenhouse gas reduction and waste policy targets or identify the maximum possible national greenhouse gas reduction based on a waste treatment system configuration. Among the seven types of waste treatment systems studied, the carbon emission factor of material recycling is the lowest (-0.19 t COre/t MSW), whereas open landfill is the highest (0.72 t C02-e/t MSW). The proposed ten waste treatment configurations indicate a 1.0-2.2% reduction of national greenhouse gas emissions, in which the best-case configuration (i.e., carbon sink scenario) contributes to 3.64% of the national electricity consumption in 2030. This study provides a compendious comparison of waste treatment systems integrated with greenhouse gas reduction and waste policy targets for a more circular MSW management in countries facing the waste disposal dilemma. [ABSTRACT FROM AUTHOR]

Economic criteria have prevailed in studies on integration of renewable energies. Tons of dangerous emissions are emitted by a biomass fuel, causing negative impacts over atmosphere and health. Current research proposes Pinch Analysis of solar thermal energy and the joint use of biomass (sugarcane bagasse) to produce heat and power in a Caribbean sugar mill; measuring emissions like: carbon oxide C O , carbon dioxide C O 2 , dinitrogen monoxide N 2 O , nitrogen oxides N O x , sulfur oxides S O x , non-methane volatile organic compounds NMVOC, methane C H 4 , and particulate matters, to have a global and clear view of the impacts of biomass as a renewable fuel. Variables like kWh cost, the installation and device area of renewable energy, and greenhouse gas emissions, are analysed to assess the effect on the integration final design, the target of which is to control the use of biomass. It is possible to produce an economically competitive integration design of solar system L C O E t h   s o l a r = 0.0636 USD/kWh, L C O E e l e = 0.1392 USD/kWh), zero greenhouse gases emissions (Δ T m i n r e w = 7   ° C ), and deletion of 378,711.53 t/year of C O 2 and 9567.56 t/year of solid particles. There are many possibilities that can implemented; in one of them, bagasse burning is reduced by 30% and the solar collector network for required power production is reduced by 68%. [ABSTRACT FROM AUTHOR]