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Throughout industrial practice, the problem is that of identifying a suitable holistic approach connecting Cleaner Production, Total Site Integration, and Energy Efficiency Optimization. The combination of all the before mentioned concepts is believed to be crucial for comprehensive assessment of the energy and environmental issues within a company. Various case studies are included within this paper regarding the implementations of cleaner production principles, energy audit performance, pinch analysis and various optimisation techniques' calculations. Several energy audits of industrial processes within the dairy, ceramic, metal processing and meat processing industries, services such as laundries and of public buildings were carried out in order to find possibilities for increasing the overall energy efficiencies of industrial processes, buildings and energy systems. On the bases of the results and the knowledge obtained from the projects mentioned in the paper, a Total Site – Cleaner Production – Energy Efficiency – Optimisation approach is proposed which enables gradual research, development and integration of Cleaner production, Energy Auditing and Optimisation combined within novel optimisation methods and its concepts. The main objective of the research was the use of analysis regarding industrial practices when developing a holistic Total Site – Cleaner Production – Energy Efficiency – Optimisation approach for supporting industrial needs during the optimisation of energy demand. This novel approach consists of three phases that include within each one the traditional Total Site Integration, Cleaner Production and Energy Efficiency – Optimization methods with a proposed novel structure for addressing the energy and environmental categories within industry. This novel approach could generate greater efficiency due to combining the different methods and consequently having a higher more positive impact on the environment. The scientific added value is demonstrated through the combination of Total Site, Cleaner Production and Energy Efficiency Optimization approaches as a comprehensive unit and by the proposal of this novel procedure for the implementation of Total Site – Cleaner Production – Energy Efficiency – Optimisation approach. [ABSTRACT FROM AUTHOR]

Energy management systems are considered as appropriate instruments to identify and realize energy efficiency potentials in industrial plants. Studies point out a largely untapped potential for energy efficiency in industry through the adoption of systematic energy management. We suggest introducing qualitative and quantitative modelling tools into energy management to facilitate a focused process to set priorities and identify effective measures. This paper describes the case of voestalpine Austria Draht GmbH, an Austrian wire rolling mill. voestalpine Austria Draht GmbH at present is implementing a knowledge based energy management system. Within the work described in this paper, first an overview of energy flows using Sankey diagrams was elaborated. Then a qualitative systems analysis was developed for the plant and a gap analysis done for priority areas. Subsequently physical input–output models for several energy intensive units were prepared. The paper describes the models for the cooling water system and product cooling. This study revealed a significant potential to save electricity by optimizing the control of cooling water pumps along the milling train and to recover heat from the final products. 2 GWh of electricity can be saved annually. The biggest single energy loss in the mill is the heat from air cooling the products on hook conveyors. These heat flows contain about 30–50 % of the energy input for heating up the billets. Following a theoretical analysis of the potential, a demonstration plant was developed and pilot tests were run to characterize the realistic potential of heat recovery on the hook conveyor. Based on the test results, feasibility studies for large scale plants were carried out. As a result, 0.8 GWh of heat can be recovered annually. The method was found useful because it helped to structure the existing information with a reasonable effort mostly by the operators themselves in their work and to build a conceptual model of energy flows and energy efficiency of the total plant. [ABSTRACT FROM AUTHOR]

Enhanced ultrafiltration process as the cleaner treatment of cutting oil wastewater has been presented in this paper. Twisted tapes as turbulence promoters were used for fouling mitigation and the enhancement of cutting oil wastewater ultrafiltration for the first time. The response surface methodology was used for modelling and analysis of the most important effects, particularly an aspect ratio of twisted tape and cross-flow rate, on the flux and specific energy consumption as responses. The improved maximal flux under minimal specific energy consumption has been obtained by the optimization of twisted tape dimension alongside the working conditions. The application of twisted tapes remarkably increases the flux. The linear effects of the cross-flow rate and the aspect ratio have a dominant positive influence on the flux. The linear effect of cross-flow rate has a positive dominant effect on the specific energy consumption. The squared effect of the aspect ratio is statistically significant and allows for optimization. The optimal flux of 201 L m−2 h−1 can be reached under specific energy consumption of 1.34 kWh m−3 with a twisted tape of the aspect ratio of 1.55 and 2% w/w oil concentration. The optimized process has the desirability of 0.81 what is beyond commercially available. Image 1 • The ultrafiltration of cutting oil wastewater was enhanced by application of twisted tapes. • Response surface methodology was used for the effects analysis and optimization of the process. • An aspect ratio of twisted tape has statistically significant linear and quadratic effects on flux. • Cross-flow rate has bigger influence on the specific energy consumption than twisted tape. • The proposed optimized process has desirability beyond commercially available. [ABSTRACT FROM AUTHOR]

Abstract Process energy consumption and environmental impact have been considered as important performance indicators for the sustainable electrical discharge machining (EDM) process. This paper presents a sustainable manufacturing technique known as magnetic field-assisted EDM (MF-EDM) to enhance the machine characteristics for the purpose of reducing the energy consumption and environmental hazards of the conventional EDM machining Ti6Al4V. Firstly, the principles of energy consumption, machining noise impact, and MF-EDM are respectively described. Thereafter, a set of experiments is carried out to investigate the effects of the main process parameters on the electrode wear rate (E W R), energy consumption (S E C), and environmental impacts (including carbon emission and machining noise) extensively, using the Taguchi method. The results indicate that the pulse on time (ranging from 100 to 200 μs) and magnetic field intensity (ranging from 0.05 to 0.10 T) are the two most significant factors affecting the MF-EDM sustainable manufacturing performance. Furthermore, the optimal process parameters were obtained by optimizing the MF-EDM process economically and environmentally using the modified non-dominated neighbor immune algorithm (M-NNIA) method. Compared to the minimum outputs of the experimental results, the optimal solutions of the E W R , S E C , and machining noise were significantly decreased, by 18.30%, 61.43%, and 20.95%, respectively. Therefore, it can be concluded from the above research that the proposed hybrid MF-EDM technique offers significant advantages and potential for applications in the sustainable manufacturing field. Graphical abstract Image 1 Highlights • A sustainable technique, magnetic field assisted EDM, is proposed to reduce energy consumption and environmental hazards. • Electrode wear rate, energy consumption, machining noise of MF-EDM processing Ti6Al4V were completely investigated. • Optimal parameter combinations were obtained through optimizing MF-EDM process economically and environmentally by M-NNIA. [ABSTRACT FROM AUTHOR]

In this paper, the optimization of the methanol production process is investigated. For this purpose, the parameters affecting methanol production including catalyst type (4 cases), temperature, pressure, and GHSV have been investigated and then by selecting the appropriate catalyst and process conditions, possible process changes such as hydrogen injection as make up, applying two reactors and inert gases, the use of dry hydrogen, and adding recycle stream on methanol yield have been studied. Then, by selecting the appropriate process, simulating, and validating the simulation results, the selected catalyst is used for the process. The process is simulated in 8 cases with changes in the studied parameters and the amount of recycle flow. Then, the key parameters of the optimized process were compared with the baseline. The results showed that, the investment costs (smaller dimensions of process equipment such as compressors, reactors, and distillation columns, etc. due to recycling flow reduction) and current costs (including electricity and steam consumption), significantly improved. In general, the use of CuZnOAl 2 O 3 catalyst in the methanol production process reduced the reactor temperature, decreased the recycle flow by about 38% and reduced the electrical energy consumption and steam consumption relative to the baseline by about 5% and 67%, respectively. Finally by the process optimization conducted in this work, in addition to reducing the recycle flow and reducing energy consumption, it is possible to annually reduce the GHG emissions of 7526.35 ton CO 2eq and 19.43 tons of air pollutants (per 100 kton/y of methanol production). • The process parameters affecting methanol production were optimized. • The recycle flow and energy consumption were reduced by 38% and 17%, respectively. • The GHG and air pollutants were decreased by about 16.9% relative to the baseline. [ABSTRACT FROM AUTHOR]

Recovering, recycling and reusing are some processes whose popularity is intense nowadays due to the increasing concern about sustainability and environmental issues. These processes are composed by some input variables that can be adjusted to optimize related relevant responses. The present paper, focusing on multiobjective optimization, proposes the Two-Phased Optimization Methodology based on the use of factor analysis, the Normal Boundary Intersection method and stochastic programming. A real application is developed in a cladding process of ABNT 1020 carbon steel plate using austenitic ABNT 316L stainless steel cored wire to exemplify the approach. The first stage of the methodology focuses on optimizing the geometric characteristics of the weld bead in order to improve the quality of the final product. The achieved values for the input variables were wire feed rate = 8.96 m/min, arc voltage = 29.38 V, welding speed = 24.21 cm/min, contact tip to the workpiece distance = 17.90 mm. From the comparison of the optimized geometry from Phase 1 with the real DoE experiments geometry, the scrap and rework areas are measured through a computer graphics software. Then, in the Phase 2, which focuses on a sustainability aspect, it is solved the multiobjective stochastic problem aiming the minimization of the scrap and rework jointly with the energy consumption. In this case, the optimized values for the input variables were wire feed rate = 9.95 m/min, arc voltage = 28 V, welding speed = 33.51 cm/min, contact tip to the workpiece distance = 25.41 mm. The methodology provides consistent results when dealing with a large number of responses considering the quality of the product and the environmental issues. • Quality and sustainability on the cladding process were investigated. • Two-Phased Optimization (TPO) methodology was proposed. • TPO results for quality were applied for the sustainability approach. • The final results shown that quality can still be hold in a sustainable process. [ABSTRACT FROM AUTHOR]

The traditional synthesis gas (syngas) production process in the coal chemical field encounters the problems of high cold energy consumption and difficulty in effectively capturing CO 2. This limits the clean production and sustainable development of coal chemical industry. To solve this problem, this paper proposes a novel process for capturing and separating CO 2 from syngas using [bmim][Tf 2 N]. This process can effectively reduce the cold energy consumption and improve the CO 2 capture efficiency, which will help relieve the global concerns over CO 2 emissions. Energy, economic, and environmental analyses of the process were conducted based on accurate modeling and simulation results. To balance the conflict between the economic and environmental performances, the non-dominated sorting genetic algorithm II method was used for the multi-objective optimization of the process. The CO 2 escape flow rate and total annual cost were the objective functions of the multi-objective optimization scheme and had values that were 5.9% and 1.5% higher than their minimum values, respectively. Moreover, the multi-objective optimization scheme for this process was compared with the Rectisol process and CO 2 capture from syngas using [emim][Tf 2 N]. This work provided new ideas for clean production of coal chemical industry, and also provided reference for the green sustainable development of relevant work. • A novel [bmim][Tf 2 N]-based CO 2 capture and separation process at 25 °C is proposed. • Energy, economic, environmental comprehensive analyses are used to study the process. • Multi-objective optimization balances the conflicting objectives of this process. • The multi-objective optimization process has feasible CO 2 capture ratio (96.34%). [ABSTRACT FROM AUTHOR]

With the increase in awareness of energy conservation and emission reduction in the manufacturing sector, the energy efficiency optimization of the production process is considered an effective way to promote cleaner production and environmentally sustainable development. Moreover, the transportation process and its energy consumption are non-negligible during the entire workshop production process. In practice, cutting tool degradation during operation is inevitable, which causes the actual processing time of work to be extended, so it is necessary to consider the degradation effects and imperfect maintenance. To reduce the total energy consumption in the manufacturing workshop with degradation effects and imperfect maintenance, this paper constructs a novel integrated optimization model including the flexible job-shop scheduling problem (FJSP), forklift transportation and imperfect cutting tool maintenance. First, an imperfect cutting tool maintenance with degradation effect strategy is presented, which makes the actual processing time of each operation more closely approximate the real-world processing situation. Second, an integrated multi-objective optimization model is formulated to simultaneously minimize the makespan, total tardiness, total production cost and total energy consumption. Third, a hybrid multi-objective evolutionary algorithm with Pareto elite storage strategy (HMOEA/P) is proposed to address the model. More precisely, three improved operations are presented: hybrid dominance principle, local search algorithms and Pareto elite preservation strategy. The effectiveness and feasibility of the parameter setting, improved operations and the proposed algorithm are separately demonstrated by the comparative experiments. Last, the superiority of the integrated multi-objective optimization model is proven by comparing different maintenance strategies and energy consumption models. [ABSTRACT FROM AUTHOR]