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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.

An offensive and prolonged smell that significantly interferes with the enjoyment and use of the affected property is known as odor nuisance. It can cause adverse health effects such as emotional unease, eye irritation, and respiratory problems. The most significant odorous gases are volatile organic compounds, nitrogen compounds including ammonia, and sulfur compounds including hydrogen sulfide. Major sources of these pollutants are animal farms, various chemical as well as food- and feed-processing industries, waste treatment or disposal facilities, and wastewater treatment plants. As more and more countries adopt regulations that prohibit business organizations from emitting strong odors, various technologies for removal of odorous compounds from waste gases are in use. Physical and chemical processes, such as activated carbon adsorption, ozone oxidation, catalytic oxidation, and incineration, are characterized by rather high energy requirements and high treatment costs. As more sustainable processes, microbiological odor treatment methods using various types of air filtration equipment are introduced. Their advantages include absence of explosion risk, operation at near atmospheric pressure and temperature range 10–40 °C, no secondary waste generation, less energy requirements. This chapter will review microbiological odor treatment methods and summarize authors’ experience of development and applications of compact trickle-bed bioreactor for odors removal from ventilation air discharged from various industrial facilities.

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.

Methods for biotreatment of polluted air streams can be classified into four main categories, namely ones using biofilters, biotrickling filters, bioscrubbers, and other bioreactor types. An important advantage of these air treatment methods over competing physical and chemical technologies is that biological processes can be conducted at moderate temperatures (10°C–40°C) and atmospheric pressure. Moreover, microbial degradation processes are generally oxidative in nature and produce compounds such as carbon dioxide, water, sulfate, and nitrate that are ecologically safe. Applications of air biotreatment date back to 1950s. Initially, simple biofilters with soil beds have been employed and later, the use of other bed materials in more advanced filter structures has been reported and more sophisticated types of filtration equipment such as biotrickling filters and bioscrubbers have been developed. On the basis of accumulated experience, some more process options and equipment types for the application of biotreatment emerged in recent years. An overview of the state of the art is provided by outlining process principles and characteristics including the use of various microorganisms and nutrients, variations in equipment design, and application ranges of the different technologies of air biotreatment.

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...

La industria de la pintura de automoviles es una fuente de contaminacion ambiental causada por los compuestos organicos volatiles (COV) presentes en el aire de ventilacion descargado. Para contribuir a la mitigacion de este tipo de contaminacion atmosferica, Ekoinwentyka Ltd. desarrollo -desde la escala piloto hasta la escala completa- y adapto la tecnologia del biorreactor de lecho de goteo compacto (CTBB), cuyo principio de funcionamiento se basa en el flujo descendente de la fase gaseosa (aire contaminado) y la fase liquida (solucion de sales minerales) a traves de un lecho empacado en el que los microorganismos activos se inmovilizan en la biopelicula de las superficies de los elementos de empaquetado. El biorreactor a escala piloto de 0,32 m de diametro y 1,50 m de altura total tenia su lecho empacado inoculado con un consorcio de microorganismos dominado por la bacteria Pseudomonas fluorescens. Durante el programa experimental, que duro varios meses, el caudal de aire extraido del sistema de ventilacion del taller de pintura variaba entre 1,0 y 10,0 m3/h y la concentracion de entrada de COV oscilaba entre 10 y 200 ppm. Al medir la concentracion de COV en el aire purificado, se comprobo que el factor de biodegradacion de los COV oscilaba entre el 85 y el 99%. A partir de los experimentos a escala piloto, se ha desarrollado un CTBB a escala real de 2,8 m de diametro y 10 m de altura total y se ha instalado como componente adicional del sistema de ventilacion del taller de pintura. Las pruebas realizadas con caudales de gas de hasta 6.000 m3/h confirmaron un factor de biodegradacion de COV del 85-99%, lo que demuestra un resultado positivo de la adaptacion de la tecnologia CTBB a las condiciones de la industria de la pintura de automoviles.

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.

Odors are emitted from agricultural and industrial activities, such as animal farms, rendering plants, wastewater treatment plants, waste treatment or disposal facilities, paint shops, oil refineries, pulp and paper mills, and various chemical industries. Effects of this kind of air pollution may include: impairment of the quality of the environment; interference with business activities; discomfort, harm or impairment of the safety of any person; rendering any property, plant or animal unsuitable for human use. Odor treatment technologies can be classified into three categories, namely ones employing chemical (thermal oxidation, catalytic oxidation, ozonation), physical (condensation, adsorption, absorption) and biological (using biofilters, biotrickling filters, bioscrubbers and other bioreactor types) treatment methods. An important advantage of biological treatment methods over physical and chemical technologies is that the biological processes can be conducted at moderate temperatures (10–40 °C) and atmospheric pressure. Moreover, microbial degradation processes are generally oxidative in nature and produce compounds such as carbon dioxide, water, sulfate and nitrate that are ecologically safe. Applications of biological odor treatment date back to 1950ties. Initially, simple biofilters with soil beds have been employed and later, the use of other bed materials in more advanced filter structures has been reported and more sophisticated types of filtration equipment such as biotrickling filters and bioscrubbers have been developed. On the basis of accumulated experience, some more process options and equipment types for the application of biological methods emerged in recent years. During more than 30 years covered by the present review, biological methods of odor treatment have matured to become a well-developed field of process technology. In order to provide an overview of the state of the art, process principles and characteristics including the use of various microorganisms and nutrients, variations in equipment design and application ranges of the different odor treatment technologies are outlined and compared.

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...

A compact trickle-bed bioreactor (CTBB) was tested for the removal of volatile organic compounds (VOCs) and hydrogen sulphide (H2S) present in the exhaust air of a wastewater treatment plant. At gas-flow rates varying between 2.0 and 30.0 m3/h and for specific pollutant loads up to 20 g/(m3·h), removal efficiencies for H2S and VOC were >95%. The CTBB was designed for a maximum H2S concentration of ∼200 ppm and removal efficiencies >97% were noticed. VOC concentrations were in the range of 25–240 ppmv and the removal efficiency was in the range of 85–99%. Possible consequences of an excessive pollutant overload and the time required for regenerating the microbial activity and reviving stable process conditions in the CTBB were also investigated. An increase in the H2S concentration from 400 to 600 ppmv for a few hours caused bioreactor poisoning; however, when original H2S concentrations were restored, stable CTBB operation was ascertained within 3 h.

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.The test (a practice and a full run, with a time limit) contained 42 questions, each with four optional choices, and could be answered online. Patients could familiarize themselves with the whole question pool first. Patients could repeat a full run attempt if they failed and were offered focused remedial education. The study group composed of adults, 46 females, and 54 males, all treated for type 1 diabetes, 38/100 newly introduced to insulin pump therapy.Eighty-five of 100 patients successfully completed their first full run attempt (80% or higher correct answers) and 3 of 100 on their second full run attempt; 12 of 100 patients were not able to succeed. The median of the test score was 2 mistakes (range 0-17 mistakes). The most problematic topics were diet and insulin regimens and their application. The crucial factor influencing the test score was the willingness to try practice run(s). Those who practiced had a significantly higher total test score with better results in 5 of 8 tested knowledge domains. Age and diabetes existing15 years had an impact on the result, too. Both patients' and caregivers' opinions on the test were predominantly positive (or neutral).The type of test introduced is a good tool for checking a patient's theoretical knowledge and indirectly revealing a patient's level of motivation.

In this paper we perceive data analysis with empirical probability functions as a data mining method. We propose a way to carry out this type of analysis by employing the LISp-Miner system, namely the CF-Miner procedure and pattern difference quantifiers. In order to confirm that LISp-Miner is a suitable tool for this purpose, we briefly present both methods and then show their equivalence. We do this by providing theoretical description which we then support by analysing a small set of data concerning traffic accidents with methods and comparing results. Afterwards we provide an example of analysis of a full data set concerning rail tickets sold at selected stations in 2014. We show that by considering “difference histograms” it is possible to identify remarkable dissimilarities in histograms of time of ticket sale that would not be found otherwise. Both analyses confirms that the method we propose can provide new and interesting results even if the data has been already analysed.

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.

Selected results are presented of an on-going project conducted by Ekoinwentyka Ltd. with the aim to design, test and apply a compact trickle-bed bioreactor – operated in a biofiltration system with circulating salt solution – to the biodegradation of VOCs, mercaptans and H 2 S contained in the ventillation air in a copper-ore mine at a depth of 1000 m underground. The experiments were performed using a 48 dm 3 semi-industrial scale bioreactor in which gas and liquid phases flowed co-currently in downward direction through a bed made of polyethylene rings. The bioreactor was inoculated with a co-culture of microorganisms including bacterial strains found in the cooper-ore mine and adopted to chosen pollutants. In the laboratory tests, biodegradation of 4-components VOC mixture (acetone, styrene, benzene, vinyl acetate) and 8-component pollutant mixture (VOCs + xylene, H 2 S, dimethyl sulfide, dimethyl disulfide) was studied. In the gas-flowrate range 2.0 – 15.0 m 3 /h and at a specific pollutant load up to 40 g/(m 3 h), values of the efficiency of pollutant removal above 80% were measured for all mixture components except benzene which caused bioreactor poisoning at a specific load above 5 g/(m 3 h). Possible consequences of a fatal pollutant overload and the time required for regenerating the microorganisms and returning to stable process conditions were also investigated. In the copper-ore mine, it was found that pollutant concentration in the ventillation air was normally low not exceeding values attained during laboratory tests but temporary bursts of very high H 2 S concentration were also detected. An increase in H 2 S concentration to 1000 ppmv lasting for 1 h caused bioreactor poisoning but after H 2 S concentration returned to normal, stable process conditions were restored within 45 min. On the basis of experiments carried out both in the laboratory and copper-ore mine, acceptable values of parameters of the biodegradation process were determined. Despite harsh working conditions that are characteristic of the copper-ore mine 1000 m deep, the experimental set-up has been working reliably for several months and a high efficiency of pollutant removal has been achieved.

As we can all experience in our daily life, the traffic in the cities grows quickly, which, unfortunately, means also that the number of accidents grows, too. We try to find causes of accidents that happen for systematic reasons as we perceive eliminating such systematic errors as one of primary goals of smart cities idea. This paper deals with the accident data analysis using Bayesian Networks and conditional probability functions. We try to examine independence between variables in data sample in order to work with data of considerably large dimension. Our approach includes determining the structure of a Bayesian Network basing on a data sample and then utilizing computed probabilities in order to eliminate insignificant relations. We also use conditional probability functions to identify significant dependences basing only on data set. Finally we compare results obtained by both methods and use Goodman and Kruskal's lambda coefficient for confirming their accuracy.

A conceptual factory to produce hydrogen from starchy biomass is considered. The production plant comprises a pretreatment unit for starchy raw material, a bioreactor for dark fermentation, a photobioreactor for photofermentation and gas upgrading & compression units, and is supplied with the necessary heat and power from the power plant. In the power plant, a part of the stream of raw gas produced in bioreactors is burned in a steam boiler and in addition some product gas from the upgrading unit is directed to fuel cells from which waste gas flows to a catalytic oxidizer. The demand for process heat is covered by steam generation in the boiler and oxidizer, and the power demand is covered by electricity generation in the fuel cells. The energy demand is studied as a function of selected process parameters; among them, CO2 content in the product gas is of key importance. Conclusions are presented regarding the practicability of using own-produced hydrogen for the energy supply.

Two-stage fermentative hydrogen production process comprising dark fermentation and photofermentation followed by gas upgrading is studied from the technical and economic points of view. It is assumed that a conceptual hydrogen plant is connected to a sugar factory so that technical sucrose solutions produced there (raw juice, thick juice and molasses) can be used as fermentation feedstocks. Process data needed for the study are based on the results of a recently completed research project and in the techno-economic assessment of hydrogen production, data acquired in the sugar industry are taken into account. A parametric study of the cost of hydrogen production from molasses shows that the total cost is highly sensitive to the capital and operating costs of the photofermentation stage. Prospects of cost reduction through further development of the two-stage fermentative process are discussed.

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.

A novel method for on-line determination of the thermal resistance of fouling in shell and tube heat exchangers is presented. It can be applied under the condition that the data on pressure, temperature, mass flowrate and thermophysical properties of both heat-exchanging media are continuously available. The calculation algorithm for use in the novel method is robust and ensures reliable determination of the thermal resistance of fouling even if the operating parameters fluctuate. The method was validated using measurement data retrieved from the operation records of a heat exchanger network connected with a crude distillation unit rated 800 t/h. Sensibility analysis of the method was carried out and the calculated values of the thermal resistance of fouling were critically reviewed considering the results of qualitative evaluation of fouling layers in the exchangers inspected during plant overhaul.

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.

This article deals with the use of data mining within the area of exploratory data analysis in fare collection systems. It describes the fare collection system and its model defined for the needs of making exploratory data analysis. The model contains inputs and outputs, internal functions and random impacts. The exploratory data analysis has been carried out both in spreadsheet and through the data mining system LISp-Miner. The conclusion of the paper outlines the possibilities of further extension and use of the GUHA procedure in the LISp-Miner system.

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.

The paper is concerned with estimation of heat and power consumption in a conceptual plant to produce hydrogen from sucrose-containing or starchy biomass by fermentation. A hydrogen plant connected with a sugar factory is regarded as the basic option; the sugar factory serves as a source of sucrose-containing thick juice for the hydrogen plant, where this feedstock is processed to hydrogen. As another option, a stand-alone hydrogen plant in which starch must initially be converted to fermentable glucose solution is considered. The values of key process parameters are assumed on the basis of preliminary experimental data. For both options of the hydrogen plant, heat consumption is estimated taking heat recovery in a heat exchanger network into account. Power consumption is estimated by calculating power needed for pumping of liquid and gaseous process media. (C) 2010 Elsevier Ltd. All rights reserved. (Less)

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.

Hydrogen can be produced through dark anaerobic fermentation using carbohydrate-rich biomass, and through photofermentation using the organic acids produced from dark fermentation. Sugar beet is an ideal energy crop for fermentative production of hydrogen in the EU due to its environmental profile and its potential availability in the area. In this work, various aspects of cultivating sugar beet in the EU for biohydrogen were highlighted, with special focus on The Netherlands and Greece. Moreover, fermentation of sugar beet juice with Caldicellulosiruptor saccharolyticus at sucrose concentration 10 g/l was performed, and was found comparable to the fermentation on pure sucrose except that the hydrogen production was 10% higher on sugar beet juice. A conservative estimate of the annual hydrogen potential in the EU was made (300 × 106 kg hydrogen), considering the utilization of sugar beet pulp in hydrogen production.

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 thermal separation of hydrocarbon mixtures is assumed to take place in a sequence of heat-integrated distillation columns (HIDiC) coupled, via a heat exchanger network (HEN), with a refrigeration system. Using the approach based on Pinch Analysis, a procedure is proposed for minimising the compressor shaftwork in the refrigeration system. The theoretical considerations are illustrated by a test example in which a mixture of selected hydrocarbons (methane, ethane, ethene, propene) is separated in a sequence of HIDiC columns coupled with a refrigeration system.