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A real-life benchmark system comprising a Heat Exchanger Network operated as part of Crude Distillation Unit is considered. In such systems, the crude oil stream is typically split into parallel branches and the oil mass flows through the branches are kept in constant proportion, i.e., at constant split ratio, by the process control system. In this paper, linear control systems (proportional-integral-derivative controllers) are considered and the proposed control strategy is to adjust the parallel flows so that identical temperature values are maintained at the outlets from two parallel branches and consequently, the heat recovery in the network is maximized. The aim is to enhance the energy efficiency of the system and minimise greenhouse gas emissions. A mathematical model of the heat exchanger network was built and validated on the basis of real-life data recorded during operation of the crude distillation unit. Using MATLAB/Simulink, closed-loop control was simulated to enable comparative evaluation of the studied strategy of proportional-integral-derivative control and its potential to achieve energy savings in the operation of the distillation unit under fouling conditions. Compared to the strategy of constant split ratio, the proposed strategy of equal outlet temperatures from the network branches was found to increase the total heat recovery by about 1.5%. In the studied operation period, the heat-recovery increase fluctuated in the range 150–1100 kW and the average daily energy saving was estimated at 18 MWh.

Introduction More sexual problems are reported among people treated for diabetes; however, this situation is less explored in women than in men. Aim To analyze the presence and causal links of female sexual dysfunction (FSD) among Czech women treated for type 1 diabetes. Methods 40 women completed a national version of the Female Sexual Function Index (FSFI), Female Sexual Distress Scale-revised (FSDS-R), and Beck’s Depression Inventory–II (BDI-II). A metabolic and endocrine analysis was done using blood samples. Data were statistically analyzed using SPSS v.24 and the R environment. Main Outcome Measures Patient details (personal information, diabetes-related data, and sex history), sexual performance (the FSFI and FSDS-R scores), and level of depression (the BDI-II score) were measured. Results FSD was present in 58% of the participants (based on the FSFI score), and 38% women declared significant sexual distress (according to their FSDS-R score). Even though only 4 women fulfilled the criteria for depression, we observed a strong association between BDI-II and FSFI (for total FSFI score P = .012, ρ = −0.394) resp. FSDS-R scores (P < .001, ρ = 0.552). Although we were not able to establish a clear direct connection between FSD and metabolic control, BDI-II scores were closely correlated with glycosylated hemoglobin (P = .009, ρ = 0.407). The duration of diabetes (based on FSDS-R: P = .046) but neither age nor the presence of chronic diabetic microvascular complications was associated with a higher FSD occurrence. We also observed an association between FSD and the presence of autoimmune hypothyroidism, even when successfully treated (FSDS-R: P = .009; FSFI: P = .067). Conclusion FSD is more common in women with type 1 diabetes than in healthy women, and coexisting thyroid autoimmune disease seems to exacerbate FSD. Women suffering from type 1 diabetes, and particularly those with additional endocrinopathies, should be actively screened for FSD.

Joint efforts and interdisciplinary approach are proper means to face the issue of global warming. An adequate response should be to employ state of the art scientific knowledge for the technology advancement, as well as for fostering new scientific insights. Together with resource efficiency, circular economy is getting in focus of researchers and consequently policymakers. Sustainable development is a multidisciplinary topic and interaction of energy, water and environment systems plays one of the central roles. Within the paradigm of circular economy, there is growing need for system integration where a by-product of one system can represent resource for the other. This review is dedicated to the 12th Conference on Sustainable Development of Energy, Water and Environment Sysmems, and discusses some latest developments in three main areas of sustainability themes: (i) Energy, (ii) Water and (iii) Environmental Systems. Examples of circular economy approach have been emphasized which improve economic efficiency of the whole chain and further decrease environmental burden, enabling cleaner production. Although integrative concept of energy, water and environmental systems is coming in the research focus, more effort is necessary for further integration of those systems, whereby increased complexity is going to be handled only by multidisciplinary, intersectoral scientific cooperation.

Sustainable development is a highly interdisciplinary concept that involves the interaction of various systems, such as energy, water, and environment. In 2002, the Sustainable Development of Energy, Water, and Environment Systems (SDEWES) Conferences were established to address this issue. In 2020, four SDEWES conferences were held—due to the COVID 19 pandemic, all of them as online events. SDEWES 2020 conferences created a temporally and spatially distributed forum for researchers worldwide to exchange and discuss their ideas and findings and show the sciences’ responsivity to national, regional, and global challenges. The overview of papers included in this Special Issue of SUSTAINABILITY is presented. The papers were chosen to match strategic importance fields of sustainable development: energy, water, buildings and infrastructure, and waste management and valorization.

Global warming and climate change call for urgent minimization of the impact of human activities on the environment. There is a great need for the improvement of resource efficiencies by integrating various life- supporting systems. The challenge is on the energy, water and environment systems to integrate and become more sustainable. This research field has received increased attention over the past years with studies across the energy, water and environment systems that optimized different engineering problems. The present Special Issue stems from four Conferences on Sustainable Development of Energy, Water and Environment Systems held in 2020, in four countries of three continents. This review introduction article intends to introduce the topical field and the articles included in this Special Issue of Optimization and Engineering.

Background: To improve insulin pump therapy results, a special test for patients was devised. The model successfully used to achieve a license to operate different machines was followed. M...

Due to climate change concerns, various environmental stresses and social inequality among the people, the welfare of mankind is increasingly being viewed through the prism of sustainable development. Sustainable development is a highly multi-disciplinary field of research that has been extensively studied during last two decades. Therefore, from the beginning of the 21st century, a series of Sustainable Development of Energy, Water and Environment Systems (SDEWES) Conferences were founded to address sustainable development issues. This Journal of Cleaner Production Special Volume (SV) is dedicated to the 10th SDEWES Conference. The SV is focused on three main fields that are of strategic importance to sustainable development: energy issues, water issues, and environmental engineering and management. The division of selected papers according to the named research fields was established following the previous Journal of Cleaner Production Special Sections and Volumes dedicated to the SDEWES Conferences. Therefore, this Special Volume builds upon the previously generated SDEWES knowledge base.

Energy-saving heat recovery in an industrial heat exchanger network may by impaired by fouling build-up on heat transfer surfaces of the exchangers. During longer periods of network operation, monitoring of fouling growth based on measurement data makes it possible to schedule and perform exchanger cleaning if needed for the mitigation of adverse effects of fouling. Three different methods of measurement-aided fouling monitoring are outlined: two simple methods known from literature and a least-squares based method introduced by the authors. A case study is performed on their hypothetical application in a real-life network of shell-and-tube heat exchangers used for heat recovery in crude distillation unit. Using historical measurement data recorded during three-year continuous operation of the network, the different methods are first employed to estimate the thermal effects of fouling and then used in the simulation of attainable energy and economic savings resulting from two alternative options of cleaning interventions in the network. The least-squares based method of measurement-aided fouling monitoring is identified as best suited for the evaluation of effectiveness of cleaning interventions in heat exchanger networks.

Engineering analyses based on the results of numerical simulation enable shortening the duration and reducing the costs of the development and tests of equipment models or prototypes. As numerical modeling methods have uncertainties, experimental verification is required. In the literature, there are many examples of application of numerical modelling to the thermal processes occurring in electric motors but the experimental methods of model validation are not so well described. In this work, numerical and experimental investigations of heat conduction in the finned housing of an electric motor, and the comparison between their results are presented. 3D geometrical model of the motor rated 7.5 kW was imported to COMSOL Multiphysics software package. After defining thermophysical properties of the housing material and heat flows generated in the motor, and setting boundary conditions, a numerical model of heat conduction in the motor housing was obtained. The model allowed to calculate steady-state temperature distribution in the housing cross section. In order to validate the model, investigations of the temperature distribution were carried out using FLIR SC7600 thermovision camera. Steady-state temperature distribution on the surface of housing of the motor run in idling conditions was recorded by thermography. The obtained thermograms were found to be in satisfactory quantitative agreement with the simulated temperature distribution as the real values of temperature differences measured across the housing cross section deviated not more than 10% from the calculated ones. The research confirmed that a thermovision camera is an efficient experimental tool for the validation of numerical models of the heat transfer phenomena in the finned housing of an electric motor.

The influence of fouling build-up on the dynamic behavior of PID-controlled shell-and-tube heat exchangers was studied. A mathematical model was proposed in which heat exchanger is considered as an array of cells where the exchange of heat is modelled using lumped-parameter approach. The model was implemented employing Simulink/MATLAB software and validated using real-life data records acquired during 3 years of operation of a heat exchanger network coupled with a crude distillation unit. Using the validated dynamic model, a simulation study was carried out on selected PID-controlled exchangers operated in the mentioned network. For different periods of uninterrupted exchanger operation, that is, at different values of the thermal resistance of fouling, suitable controller tuning parameters were studied. The results proved that at changed thermal resistance of fouling, the values of tuning parameters should be changed too.

Objective: To assess the plausibility of using the continuous glucose monitoring as a sole source of data for the screening of the neonatal hypoglycemia.Study design: Infants of mothers wit...

Following the 2015 Paris Agreement, the main challenge for world economies nowadays is to commit themselves to long-term reforms aimed at increasing and promoting sustainable, inclusive and balanced development. An adequate response to this challenge will certainly require using the best available scientific knowledge and constant re-evaluation of the development process in light of the scientific findings. To ensure that the sciences are responsive to the emerging needs and to address sustainable development issues. This Virtual Special Issue of the Journal of Cleaner Production is dedicated to both Sustainable Development of Energy, Water and Environment Systems 2016 Conferences – 2nd South East European Sustainable Development of Energy, Water and Environment Systems Conference and 11th Sustainable Development of Energy, Water and Environment Systems Conference. The Virtual Special Issue is focused on four main fields: Energy issues, Water issues, Environmental engineering and management, and Sustainable engineering solutions and large-scale sustainability approaches. The division of selected papers follows the previous Journal of Cleaner Production Special Sections and Volumes dedicated to the Sustainable Development of Energy, Water and Environment Systems Conference series.

It is now widely recognized that considerable amounts of hydrogen can be produced from renewable resources without using energy from fossil fuels. Biological processes and mainly bacterial hydrogen fermentation are considered as the most environmentally friendly alternatives for satisfying future hydrogen demand. In particular, biohydrogen production from agricultural and agro-industrial solid waste and wastewater is considered as highly advantageous as materials of this kind are abundant, cheap and biodegradable. Apart from economic considerations, the conversion of such materials into hydrogen is in many cases stimulated by the need to solve environmental problems. However, the suitability of various kinds of biomass-derived feedstock for industrial-scale hydrogen production is widely differentiated. In this paper, on the basis of numerous research contributions published mainly in the period 2008–2013, recent findings on the use of biomass residues and waste for biohydrogen production by bacterial fermentation are reviewed. The focus is on second generation (lignocellulosic) biomass substrates that are most widely available but can be fermented only after appropriate pretreatment which is rather costly at present and therefore requires further development. Research results pertaining to the use of selected sugar-containing and starchy residues are also mentioned as the conversion of these materials into biohydrogen is not in competition with food production, and their pretreatment is cheaper than that of lignocellulosic biomass. In addition to an extensive literature review, the state of the art in the area of pretreatment of biomass residues for hydrogen fermentation is evaluated, and the authors' view of challenges for future research is presented.

The focus of this Special Volume (SV) of the Journal of Cleaner Production is “Sustainable Development of Energy, Water and Environmental Systems”. It is of interest to practitioners in various branches of industry including the energy and water & wastewater sectors and environmental services, governmental policy makers, researchers, educators and the general public. The purpose of this SV is to increase public awareness of key issues of sustainable development and to stimulate exchange of research results, practical experience and new ideas among actors involved in investigating, planning and implementing sustainable development, regarding energy, transport, water, environment and production systems. The SV is focused upon four main fields that are of strategic importance to the sustainable development: energy resources and energy management, water management and wastewater treatment, environmental engineering and management, and promotion of sustainability concepts. The systems under consideration are differentiated in scale, ranging from countries or groups of countries, through regions or branches of industry, municipalities or industrial plants, down to single processes or equipment pieces. Examples of on-going research including case studies are presented along with examples of innovative practical solutions. In the energy field, examples are presented of the development and applications of energy systems analysis, planning and design methods and tools, which can be used to analyse the coherency of the whole systems and to augment the creation of sustainable energy policies and action plans on a large scale, as well as small-scale systems for efficient energy management. Regarding water issues, water management in water stressed regions is discussed indicating the usefulness of advanced mathematical models that take system dynamics and the stochastic nature of rainwater availability as planning tools, and LCA-based methods for assessing the diverse water supply alternatives within a dry region. In the field of environmental engineering and management, large-scale systems for solid waste collection, management and recovery are analysed, and the formation of air pollutants in industrial sources and diesel engines is studied by simulation. Finally, sustainable use of biomass resources and the role of sustainability thinking in the investment planning and management are addressed. In each of the four fields, strategically important challenges for future research are identified including the use of advanced mathematical models and multi-criteria analysis for the optimisation, from the sustainability point of view, of the systems for energy and water supply and management, solid waste management and the utilisation of biomass resources.

Fermentative hydrogen production from molasses—a renewable by-product of beet-sugar processing—was considered. Technical and economic evaluations were performed of a stand-alone production plant employing a two-step fermentation process (dark thermophilic fermentation and photofermentation) followed by an adsorption-based upgrading of the produced hydrogen gas. Using a state-of-the-art knowledge base and a mathematical model composed of mass and energy balances, as well as economic relationships, the process was simulated and equipment data were estimated, the hydrogen cost was calculated and a sensibility analysis was carried out. Due to high capital, operating and labor costs, hydrogen production cost was estimated at a rather high level of 32.68 EUR/kg, while the energy output in produced hydrogen was determined as 68% more than the combined input of the thermal and electric energy needed for plant operation. As the room for improvement of plant performance is limited, a perspective on the cost competitiveness of large-scale hydrogen production from fossil sources is unclear.

The present work is an extension of the authors&rsquo, previous research, where changes in the dynamic behavior of heat exchangers induced by fouling build-up were studied. In the present work, the authors used the previously elaborated and validated mathematical model of transient heat exchange with the influence of thermal resistance of fouling taken into account. The behavior of specific Heat Exchanger Networks (HENs) coupled with a Crude Distillation Unit together with their control loops is simulated using Simulink/MATLAB and the influence of fouling build-up on specific indices of quality of operation is investigated. According to the presented results, the higher the number of heat exchangers in the PID control loop and the greater the number of heat exchangers interacting in the network, the smaller the influence of fouling on the control quality indices, and in the extreme case, this influence may be negligible. This might be caused by the compensation of the negative effects of fouling build-up when the heat exchangers are interacting in the HEN. Nevertheless, potential adverse effects of fouling on HEN operation can be prevented by periodic adjustments of the optimal values of PID gains.

The aim of this work is to elaborate a method of identification of the influence of fouling on the heat recovery in a heat exchanger network (HEN). The method is based on mathematical models enabling the interpretation of industrial measurements of operating parameters of the HEN. Details of the models are developed for shell and tube heat exchangers. The crucial assumption is that measurements of the mass flowrate and inlet and outlet temperature, and chemical composition are available for each process stream, this making it possible to evaluate fouling-induced reduction in the recovered energy flow. Using the proposed identification method and an industrial data base acquired in a typical crude distillation unit, the mathematical models are thoroughly tested. The developed approach allows long-term monitoring of changes in the condition of the HEN and assisting plant operator decisions aimed at maximizing heat recovery over the period of plant operation. A case study and an example of optimal scheduling of cleaning interventions on the individual exchangers are presented.

The cement production industry worldwide is one of the largest CO2 emitting industrial sectors. It accounts for a considerable amount of total global greenhouse gas (GHG) emissions. Due to the increasing awareness of global warming, more energy efficient cement production is increasingly being emphasized. One of the priorities is to reduce the energy demand and innovate the production process to move towards the cleaner production as: Energy efficiency improvements; Waste heat recovery; Reduction of clinker/cement ratio and use of alternative raw materials; Substitution of fossil fuels with alternative energy sources. When the GHG emissions at source opportunities are close to being exhausted, the other mitigations options should be considered such as: CO2 capture and storage. This is however in most cases not the final solution from the point of Life cycle assessment (LCA). In recent years various mitigation measures are gaining on the importance and the cement industry is more and more shifting to cleaner production. Among the others, there are two measures, which can reduce the GHG emissions considerably: the use of alternative raw materials and alternative fuels. The challenge for the cement industry is to use alternative raw materials especially those originating from other industries where they are considered as by-products or even waste. Some of these by-products include: Bottom ash from municipal solid waste incinerators; Fly ash from coal power plants; Gypsum from the desulfurization plants used in power plants. Another important measure is the energy efficiency improvement in existing cement plants. There are various approaches for controlling and improving the energy efficiency within existing cement manufacturing units, however, mathematical modelling, simulation, optimisation and Process Integration are increasingly gaining in importance. The mathematical modelling approach uses the numerical simulations for the investigation of the thermo-chemical processes occurring inside of the manufacturing unit. The results gained are being used to enhance the efficiency of cement production. They improve the understanding of the flow characteristics and transport phenomena taking place inside the cement combustion unit. The objective of this paper is to review the current status of the cleaner cement manufacturing, the cement industry's shifting to alternative raw materials and alternative energy sources, and the modelling of the thermo-chemical processes inside the cement combustion units. Additionally, some critical issues, which up to now have not been adequately resolved, are outlined.

One of the main issues of the coming decades is to improve resource efficiencies by integrating various life supporting systems, using waste from one, as resource in other, and in exact moment when it is beneficial to all. The challenge is on the electricity, heating, cooling, transport, water, buildings, industry, forestry and agriculture systems to integrate and become more sustainable. Since the sustainable development depends more and more on the holistic approach on the integration of energy, water and environment systems, from the beginning of the 21st century, a series of Sustainable Development of Energy, Water and Environment Systems (SDEWES) Conferences has been founded to cover these issues. The background of this Special Section of the Journal of Cleaner Production is therefore the Sustainable Development of Energy, Water and Environment Systems dedicated to both SDEWES 2014 Conferences - 1st South East European SDEWES Conference and 9th SDEWES Conference. The Special Section focuses on scientists, researchers, policy makers, educators, general public and practitioners in various branches of industry including the energy and water & wastewater sectors and environmental services. The purpose of this Special Section is to increase public awareness of key issues of sustainable development and to stimulate exchange of research results, practical experience and novel ideas among actors involved in investigating, planning and implementing sustainable development. The Special Section is focused upon four main fields that are of strategic importance to the sustainable development: Energy issues ; Water issues ; Environmental engineering and management ; Sustainability approaches and promotion of sustainability concepts. The division of selected papers according to the named research fields has been established by the previous Journal of Cleaner Production Special Sections and Volumes dedicated to the SDEWES 2013 Conference. Hence, this Special Section is an extension of the previously generated SDEWES knowledge base in these four main research areas. As sustainable development is improving piecewise, so although it is necessary to see the big picture, actual technological improvement is one aspect of the technology systems. It has been shown that the sustainability can be improved by improving certain systems taking care of holistic sustainability criteria or integrating various systems in a way to improve the efficiency or resource efficiency of the combined system.

Fermentation of biomass residues and second generation biomasses is potentially a way to enable a sustainable production of hydrogen. Simulation models which calculate mass and energy balances, developed with Aspen Plus (R), are used to integrate the process steps necessary to produce pure hydrogen from biomass in a 2-stage fermentation process. Process and heat integration are introduced to reduce the high water and heat demand of the process, connected to the low substrate concentrations in the involved process streams. The results show that the recirculation of process effluents, together with the use of properly designed heat exchangers, can reduce the water and heat demand up to 90% from a non-integrated process, but is also subject to restrictions due to an increase in osmolality in the system. (C) 2010 Elsevier Ltd. All rights reserved.

The basics of hydrogen production by thermophilic fermentation and photofermentation are outlined. Various types of biomass, which can be used as raw materials for hydrogen fermentation are named and the methods of biomass pretreatment are highlighted. The approach to technical assessment of biomass suitability is reviewed and several promising raw materials are compared with respect to the attainable hydrogen yield.

The paper deals with detection of clusters in data measured on a driven vehicle. Such a clustering aims at distinguishing various driving styles for eco-driving and driver assistance systems. The task is solved with the help of the application of the recursive Bayesian mixture estimation theory. The main contribution of the paper is a demonstration that real measurements with non-linear relationships between them can be approximately described by the mixture model, which is known as the universal approximation. Validation experiments are shown.

In the past years we evaluated different strategies with the aim of eliminating completely from the beet sugar factory, the traditional calco-carbonic purification process taking into account the well-known problems related to the utilization of lime and the production of carbonation sludge. To complete the picture of the possible solutions to be adopted for the elimination of the traditional purification process, we tested and evaluated in laboratory and in pilot plants a new eco-friendly proposal. The results obtained, as well as the proposed flow-sheet and some economic evaluations, are presented and discussed.

In process plants incorporating heat exchangers networks for heat recovery, fouling of heat-transfer surfaces hinders correct production activity and increases energy consumption thus giving rise to economic losses. The losses can be reduced if on-line cleaning of heat exchangers is applied. The scheduling of cleaning interventions on the individual exchangers in the HEN can be based on a priori knowledge of the time behaviour of the thermal resistance of fouling. In this paper, the mathematical model of the influence of fouling on heat exchanger and HEN operation is outlined and an example of its application is presented. Heat exchanger cleaning is postulated to maximise the avoided loss understood as the value of energy recovered if cleaning the HEN, minus the value of energy recovered without HEN cleaning, minus the cost of HEN cleaning. The mathematical formulation of the avoided loss is given and the computational approach to its maximisation is outlined. The example of optimal scheduling of cleaning interventions in a HEN comprising 10 heat exchangers is considered and numerical results are presented.

The main structural features of a multistage evaporator station are identified and their dependence on the requirements relating to the beet-sugar process is discussed. Developments in the scheme of multistage evaporation and preferred evaporator design over the recent decades are reviewed. Approaches making it possible to optimise the multistage evaporator station are mentioned and two examples of advanced stations implemented in beet-sugar factories by retrofitting outdated evaporation equipment are presented. It is stressed that the optimum retrofit results can be achieved by simultaneously reconstructing the evaporator station and the associated heat exchanger network.

Report is given on the 18th Word Hydrogen Energy Conference held on 16--20 May 2010 in Essen, Germany. Basic facts about conference organization, and its goal, scientific programme and conclusions are reviewed.

Sugar factory retrofit often includes improvements in the factory’s energy system comprising power plant, multiple-effect evaporator and process heating equipment. To reduce the energy consumption, the evaporator subsystem and the process heating subsystem should be retrofitted to make improved heat recovery possible. The retrofit design procedure includes two stages: targeting for various options of the evaporator structure and selecting the most promising one, and designing both subsystems for targets so determined. At the targeting stage, one is confronted with the problem of designing the evaporation process and simultaneously considering the energy consumption. This constitutes an extension of the established targeting approach that assumes process conditions to be fixed. The problem can be transformed by decomposing the energy system, that is, conceptually separating the evaporator (in which vapours and condensates are generated) from the process heating subsystem (in which these heat carriers can be regarded as utilities). The transformed problem is one of targeting under constraints and can be solved iteratively by combining pinch analysis algorithm with evaporator simulator. The second stage of the retrofit design procedure requires defining the details of process heating subsystem that includes a heat exchanger network. This problem is conveniently solved using the network pinch approach.

This chapter discusses the applications of Process Integration methods to the design of energy systems, and water and wastewater systems, of beet sugar plants. Characteristic features of conventional sugar plants based on purification of raw beet juice and evaporating crystallisation are reviewed, the design of plant retrofit aimed at improvements in energy and water use is discussed, and case studies are presented. A concept of the sugar production process based on cooling crystallisation of raw beet juice is then outlined, and the design of an energy system and a water and wastewater system for a conceptual beet sugar plant employing the new process is discussed.

The 7th International Conference on Environmental Engineering and Management (ICEEM07) was held on September 19–20, 2013 at Vienna University of Technology, Austria. Organized in close cooperation with the Environmental Biotechnology section of the European Biotechnology Federation, it was dedicated to integrating cutting-edge environmental technologies with efficient management practices, contributing thus to a sustainable future.

Future production of hydrogen must be sustainable. To obtain it, renewable resources have to be employed for its production. Fermentation of biomasses could be a viable way. The process evaluated is a two-step fermentation to produce hydrogen from biomass. Process options with barley straws, PSP, and thick juice as feedstocks have been compared on the basis of process balances. Aspen Plus has been used to calculate mass and energy balances taking into account the integration of the process. Results show that the production of hydrogen as energy carrier is technically feasible with all the considered feedstocks and thanks to heat integration, second generation biomass (PSP and barley straws) are competitive with food crops (thick juice).

The topic of this special issue of the Journal of Cleaner Production is “Sustainable Hydrogen from Biomass.” It is of interest to practitioners in the energy sector, governmental policy makers, researchers, educators, as well as to the general public. The purpose of this special issue is to increase public awareness and to stimulate exchange of information among actors expected to play important roles in making hydrogen available for the sustainable energy system of the future. Hydrogen as a biofuel, that is, hydrogen produced from biomass in a sustainable way is recognised as an important component of the fuel market for the future low or non-carbon based energy systems. In this special issue, the main focus is on hydrogen produced from vegetable biomass by fermentation. The development of a two-stage bioprocess for the cost-effective and environmentally friendly production of pure hydrogen from multiple biomass feedstocks is elucidated by a collection of papers presenting preliminary results of Integrated Research Project HYVOLUTION supported by the 6th Framework Programme of the European Union. The attention is turned to: - the over-all concept and characteristics of the two-stage hydrogen fermentation process, - key technological issues of fermentative hydrogen production, - the availability of vegetable feedstocks including agricultural byproducts that suitable for fermentative processing, - prospects of societal integration and sustainability of the fermentative hydrogen production technology. Other papers included in this special issue are devoted to: - simultaneous production of hydrogen and methane by fermentation of lactose-containing feedstocks derived from byproducts of milk processing, - hydrogen gas generation from organic material by electrohydrogenesis, that is, a bioelectrochemical process performed in reactors known as a microbial electrolysis cells, - the ideas for Europe-wide effort on education of hydrogen users and training of skilled staff needed for facilitating the transition to the future hydrogen economy.

Publisher Summary This chapter presents that, in recent decades, world output of sugar has tended to exceed demand causing a surplus situation in the world sugar market so that investments in new sugar factories are very rare. For economic and environmental reasons, however, there is a constant need for reconstruction of sugar factories. The dominant trend is to increase the production rate and take advantage of technological advances in sugar production and environment protection. Energy efficiency may be an important issue in factory reconstruction as the fuel cost in some cases is of the order of several per cent of the cost of sugar production; fuel burning in the power house is usually responsible for a major part of atmospheric emissions. Consequently, sugar factory retrofit typically includes improvements in the factory's energy system to reduce fuel consumption. As water and steam are used as energy carriers, improvements in the energy system may generate opportunities for improvements in water management. Apart from that, factory reconstruction measures aimed at reducing water consumption and wastewater discharge are required to satisfy environmental regulations that are becoming increasingly stringent. A retrofit strategy that is of particular interest to sugar factory operators involves reducing energy consumption by improving heat recovery and reducing water consumption by optimizing the throughput of existing wastewater treatment.

Report is given on the 19th World Hydrogen Energy Conference held on 3–7 June 2012 in Toronto, Canada. Basic facts about conference organization, and its goal, scientific programme and conclusions are reviewed.

The 6th Dubrovnik Conference was held on September 25–29, 2011 at the University of Dubrovnik, Croatia. It was dedicated to the improvement and dissemination of knowledge on methods, policies and technologies for increasing the sustainability of development of energy, transport, water and environment systems.

The paper is based on the results of international project entitled “Towards Sustainable Sugar Industry in Europe (TOSSIE)”. 33 research topics of major importance to the sugar sector are listed and briefly described, and compared with research priorities of the European Technology Platforms: “Food for Life”, “Sustainable Chemistry”, “Biofuels”, and “Plant for the Future”. Most topics are compatible with the research themes included in the COOPERATION part of the 7th Framework Program of the EU (2007-2013). However, some topics may require long-term R&D with the time horizon of up to 15 years. The list of topics is divided into four parts: Sugar manufacturing, Applications of biotechnology and biorefinery processing, Sugarbeet breeding and growing, Horizontal issues. Apart from possible use of the list by policy- and decision makers with an interest in sugarbeet sector, the description of each research topic can be used as a starting point in setting up a research project or other R&D activities.