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The construction of flexible electrochemical devices for energy storage and generation is of utmost importance in modern society. In this article, we report on the synthesis of flexible MoS2-based composite paper by high-energy shear force milling and simple vacuum filtration. This composite material combines high flexibility, mechanical strength and good chemical stability. Chronopotentiometric charge–discharge measurements were used to determine the capacitance of our paper material. The highest capacitance achieved was 33 mF·cm−2 at a current density of 1 mA·cm−2, demonstrating potential application in supercapacitors. We further used the material as a cathode for the hydrogen evolution reaction (HER) with an onset potential of approximately −0.2 V vs RHE. The onset potential was even lower (approximately −0.1 V vs RHE) after treatment with n-butyllithium, suggesting the introduction of new active sites. Finally, a potential use in lithium ion batteries (LIB) was examined. Our material can be used directly without any binder, additive carbon or copper current collector and delivers specific capacity of 740 mA·h·g−1 at a current density of 0.1 A·g−1. After 40 cycles at this current density the material still reached a capacity retention of 91%. Our findings show that this composite material could find application in electrochemical energy storage and generation devices where high flexibility and mechanical strength are desired.Keywords: flexible composites; hydrogen evolution reaction (HER); lithium ion batteries (LIBs); molybdenum disulfide; nanoarchitectonics; supercapacitors

Power consumption is becoming more expensive by the day. This is not far from the fact that power generation is facing a lot of challenges coupled with increasing demand. Industrial sector power demand shares a significant proportion of this generated power. It is therefore a necessary task to manage well industrial energy use through appropriate energy efficiency methods practice so as to minimise energy losses. In this study energy efficiency opportunities in pulp and paper (P&P) mill are identified and the saving potential is then quantified. An energy flow model with the help of an energy audit are used to quantify energy supply, generation, conversion and end use thereby exposing areas of energy losses of the mill. This analysis will serve as an eye opener to future and current P&P making operations in South Africa, and as a base case for stimulating changes toward more efficient energy utilization in the pulp and paper industry. Quite a reasonable energy losses avenues were identified, audited and options of improvements suggested. The results proved that quite a sensible amount of energy is lost in the P&P case study and a near future look into the opportunities and barriers have been noted.

Purpose This paper aims to measure the state-level energy efficiency in Indian paper industry and simultaneously explain inter-state variation in efficiency by inefficiency effect model. Three variables, labor productivity, capital intensity and structure of paper industry, are included in inefficiency effect model to assess the likely impact on energy efficiency. Design/methodology/approach Sub-vector input distance function is derived through neo-classical production function which provides measures to estimate energy efficiency. Assuming a translog production function specification, energy efficiency is estimated by using Battese and Coelli (1995) stochastic frontier analysis (SFA). The authors also estimated four other SFA models, and energy efficiency from all the models is compared for robustness checking. Findings The results show the existence of a vast potential to improve energy efficiency. Inefficiency effect model reported a positive impact of structure of the industry and capital intensity on energy efficiency performance, while labor productivity does not have any significant impact on energy efficiency. There exists considerable energy efficiency variation among states. Uttarakhand, Punjab and Orissa are the best performing states while Rajasthan, Jharkhand and Goa have worst energy efficiency performance based on average efficiency. The ranks assigned to states according to inefficiency effects model are found contrary to the simple measure of energy efficiency, i.e. energy intensity. Thus, energy intensity may not always be a good proxy for underlying energy efficiency and need to be compared with a comprehensive possible measure. Originality/value To the best of the authors’ knowledge, this is the first study which measures energy efficiency of Indian paper industry through stochastic frontier model using region-level data. Instead of relying on traditional energy efficiency indicators (energy-output ratio), total-factor energy efficiency approach is used to conduct the empirical exercise. Deviations from the frontier because of factors beyond the scope of producers are also incorporated into analysis to portray the magnitude of random factors in influencing the efficiency performance.

Thanks to their versatile functionality, metal oxides (MOs) constitute one of the key family materials in a variety of current demands for sensor, catalysis, energy storage and conversion, optical electronics, and piezoelectric mechanics. Much effort has focused on engineering specific nanostructure and macroscopic morphology of MOs that aims to enhance their performances, but the design and controlled synthesis of ultrafine nanostructured MOs in a cost-effective and facile way remains a challenge. In this work, we have exploited the advantages of intrinsic structures of graphene oxide (GO) papers, serving as a sacrificial template, to design and synthesize two-dimensional (2D) layered and free-standing MO papers with ultrafine nanostructures. Physicochemical characterizations showed that these MO materials are nanostructured, porous, flexible, and ultralight. The as-synthesized materials were tested for their potential application in photoelectrochemical (PEC) energy conversion. In terms of PEC water splitting, copper oxide papers were used as an example and exhibited excellent performances with an extremely high photocurrent-to-weight ratio of 3 A cm-2 g-1. We have also shown that the synthesis method is generally valid for many earth-abundant transition metals including copper, nickel, iron, cobalt, and manganese.

Recently, radioactive wastes are inevitable by-product due to rapid development and use of nuclear energy. Especially, there are large amount of liquid radioactive wastes to control nuclear fission reaction at nuclear generating station. In order to reduce total volume of solution state radioactive wastes, people have used solar evaporation without any specific instrument and it takes long time to get liquid state concentrated radioactive waste which is inefficient process. Herein we propose Janus-type membrane with different surface hydrophilicity toward efficient solar steam generation to concentrate radioactive liquid wastes. We used vapor deposition polymerization method to introduce polypyrrole (Py) and polystyrene (PS) on the top and bottom side of a cellulose paper. Py coating broadens the absorption wavelength range for enhanced photo-thermal energy conversion. Hydrophobic PS coating not only makes membrane easy to floating on water but also prevents salt accumulation during evaporation. Using this membrane, we can efficiently concentrate polluted water including Cs ion without salt accumulation on membrane, and thus no specific decrement in evaporation efficiency by time.

This work deals with the mass, energy and exergy analyses of the energy conversion process in a 50 MWth thermal power plant, using residual forest biomass as fuel and integrating bubbling fluidized bed combustion technology. This is a representative case study of the energy production from eucalyptus residual biomass in the Portuguese pulp and paper industry. Analyses are made of the mass, energy and exergy flows, and how they change in the main components of the system, namely the combustion chamber, boiler, drum, superheater, economizer, and combustion air pre-heaters. Sankey and Grassmann diagrams highlight the mass, energy and exergy flows. Special emphasis is given to the energy and exergy efficiencies, which must be based on the useful produced superheated steam to include the influence of the biomass moisture content. The main goal is to find where and what potential exists for energy efficiency improvements. Results show that the main exergy destruction occurs in the combustion process, and that energy and exergy losses are minimal due to the system’s good thermal insulation. Results also show that the main potential for improvement is on the decrease of the residual biomass moisture content.

Being inspired by the “seismonastic reaction” of Mimosa pudica, an asymmetric swelling system was constructed to induce the controllable directional deformation of filter paper. In this work, multifunctional biomimetic Janus paper was facilely fabricated via depositing poly(vinylidene fluoride) (PVDF) on one side of Qualitative Filter Paper (QFP), the permeation of polymer solutions within filter paper was well controlled during fabrication. The wetting and swelling behavior of the prepared Janus paper were detected. The Janus paper showed controllable swelling-induced deformations in water. Both the degree and orientation of the deformation were fully investigated. On the one hand, the degree of deformation depends on the gradient wettability and hygroscopicity of the Janus paper, on the other hand, the orientation of deformation is related to the storage and release of stress. Additionally, the steady deformation during swelling endows the Janus paper with novel shape memory property both under idling and loading conditions. The Janus paper was also applied to achieve reversible energy conversion from the swelling potential energy to mechanical potential energy.

This Special Issue on “Selected papers from IEEE ICKII 2019” selected 13 excellent papers from 260 papers presented in IEEE ICKII 2019 on topics in energies. The fields include: energy fundamentals, energy sources and energy carriers, energy exploration, intermediate and final energy use, energy conversion systems, and energy research and development. The main goal of this Special Isue is to discover new scientific knowledge relevant to the topic of energies.

As promising fresh-water purification devices, solar steam generation systems have attracted significant attention recently. However, in practice, the approach often suffers from a poor solar energy conversion efficiency and a low water production rate due to poor material selection and inefficient microscopic structure design. Here, we fabricate an efficient solar steam generation system by "building" polyoxometalate "nano-walls" on rice paper-derived three-dimensional porous carbon paper. In this solar steam generation system, the height of the vertically aligned CoP4 Mo6 "nano-walls" range from 100 to 150 nm with thicknesses about 15 to 25 nm. Under 1 sun irradiation (1 sun = 1 kW m-2 ), the surface temperature increases from 29 to 50 °C in a short time with a solar thermal conversion efficiency achieving 92.8 %. The stability and durability of this solar steam generation system, which withstands fifteen cycle continuous tests, also offer good prospects. Its attractive solar energy conversion performance originates from the intense sunlight absorption and high conversion ability of the CoP4 Mo6 "nano-walls", as well as extremely promising heat localization and water transportation properties of the three-dimensional porous carbon paper. This solar steam generation system, which has produced some inspiring results, is employed for seawater desalination and for purification of water polluted with organic dyes.

Flexible electronics are developing rapidly due to promising applications in displays, sensors, and energy conversion fields. For biodegradable, lightweight, and flexible thin film electronics to be explored, O-(2,3-Dihydroxypropyl) cellulose (DHPC) was synthesized by homogeneous etherification of cellulose in 7 wt % NaOH/12 wt % urea aqueous solution without extra catalyst. DHPC exhibited a high level of transparency, outstanding ductility, and good adhesiveness but poor mechanical properties. Thus, stiff tunicate cellulose nanocrystals (TCNCs) were introduced to construct tough nanocomposite papers. The reinforcement of nanocomposite papers was well predicted by a percolating model, indicating the formation of the network of TCNCs. On the basis of the excellent interfacial compatibility between TCNCs and DHPC, supported by atomic force microscope mapping, the nanocomposite papers exhibited smooth surface, high transparency, as well as satisfactory mechanical properties, which were suitable for the const...

Harvesting energy from environmental moisture is a promising technique for sustainable electric power resource. Herein, a new scalable fabrication method for flexible moisture-electric energy transformation device by dispersing or direct printing carbon dots (CDs) on paper is reported. A facile strategy for self-establishing ionic gradient on both sides of the device by constructing an asymmetric structure (the side of device is encapsulated) is proposed, which avoids prior processing of the materials for building asymmetric functional groups. The carboxyl groups on CDs near the open side of the device ionize more protons than that near the closed side, resulting in a potential drop across the device due to the concentration difference of the released protons on the two sides. The device can produce a sustainable voltage of −40 mV for over 100 min at a fixed humidity value. In addition, the device responds to direct touching of a finger or human exhalation, thus indicating its great potential for applications in electronic skins and humidity sensors.

Nowadays, multi-functional systems driven by solar energy have been explored to alleviate the crisis of energy and freshwater scarcity. However, it remains a great challenge to integrate multi-functions into one hybrid system with a monolithic material, which can harvest, convert and store solar energy synergistically. Here, we firstly propose a multi-functional carbon nanotube paper, which starts from a material level to solve these problems. The carbon nanotube paper is fabricated by vacuum filtration. It exhibits high efficiency of solar-thermal conversion. Secondly, three types of energy conversion/storage systems (e.g., solar-thermal evaporation system, solar-thermoelectric generation system, and supercapacitor) are constructed based on the carbon nanotube paper, which extend the research to a device level. The solar-thermal evaporation system shows an evaporation rate of 1.28 kg m-2h−1 under simulated sunlight irradiation of 1 kW m−2. The solar-thermoelectric generation system demonstrates a stable electric power generation with an output voltage of 100 mV under light irradiation of 1 kW m−2. The supercapacitors perform the energy storage function with an areal specific capacitance of 19.6 mF cm−2. These devices and systems can be used in freshwater generation (0.84 kg m-2h−1, sunlight irradiation of 1 kW m−2), water purification/desalination (inorganic ions rejection larger than 99.9%) and portable solar charging system (maximum output voltage of 5 V). Finally, a hybrid energy system is innovatively proposed from the system level to simultaneously produce freshwater, generate and store electric power. Through the synergetic coupling of solar conversion and storage technologies, the hybrid energy system can supply sustainable freshwater and electricity for remote areas in daily life, highlighting the superiority of multi-energy (thermal energy, electrical energy, and electrochemical energy) complementary.

Herein, porous WP 2 nanosheet arrays integrated on graphite paper (P-WP 2 NSs/GP) as 3D flexible cathode for electrocatalytic hydrogen evolution reaction (HER) are prepared by in situ phosphidation via vacuum encapsulation assisted by pulsed laser deposition technique. Compared to the electrode without pre-deposition process, the enhanced catalytic activities are attributed to the increased effective catalyst loading and the reinforced charge transport kinetics. The results make the present P-WP 2 NSs/GP as a promising cathode for energy conversion and paves a new way for designing and fabricating efficient electrodes toward HER.

Lithium-Air batteries (LABs) are considered as one of the most promising energy conversion systems for delivering large specific energy. However, practical applications still face major challenges, including poor rate capability, short cycle life and low round-trip efficiencies. Here we report a novel strategy to improve the catalytic activity of MnO2 through the combination of three-dimensional (3D) MnO2 and carbon nanotubes/carbon fiber paper (CNTs/CFP) with binder-free structure. Side reactions related to the binder are precluded in this design. The presence of CNTs not only promotes the formation of 3D structure of air electrode, but directs the uniform deposition of MnO2. When applied as a cathode in LABs, the as-prepared MnO2/CNTs/CFP electrode achieves comparable specific capacity (with a discharge capacity of 8723.5 mAh∙g-1(CNTs+MnO2) at 100mA∙g-1). The encouraging electrochemical performance is found to benefit from free-standing nanoporous structures, which provide more active sites for enabling oxygen reduction. It is also attribute to the decreased side reactions.

It is our great pleasure and honor to present this special issue of Heat Transfer Engineering to highlight some of the research works presented at the AIGE 2016 Conference on Energy Conversion, Man...

Construction of flexible electrochemical devices for energy storage and generation is of utmost importance in the modern society. In this article, we report the synthesis of flexible MoS2 based composite paper by high-energy shear force milling and simple vacuum filtration. This composite material combines high flexibility, mechanical strength and good chemical stability. Chronopotentiometric charge-discharge measurements were used to determine the capacitance of our paper material. Highest capacitance of 33 mF cm-2 was achieved at current density of 1 mA cm-2 showing potential application in supercapacitors. We further used the material as a cathode for hydrogen evolution reaction (HER) with an onset potential of ca. -0.2 V vs RHE. The onset potential was even lower (ca. -0.1 V vs RHE) after treatment with n-butyllithium suggesting the introduction of new active sites. Finally, a potential use in Lithium ion batteries (LIB) was examined. Our material can be used directly without any binder, additive carbon or copper current collector and delivers specific capacity of 740 mA h g-1 at a current density of 0.1 A g-1. After 40 cycles at this current density the material still reached a capacity retention of 91%. Our findings show that this composite material could find application in electrochemical energy storage and generation devices where high flexibility and mechanical strength are desired.

Solar photovoltaic technologies could fully deploy and impact the energy conversion systems in our society if mass-produced energy-storage solutions exist. A supercapacitor can regulate the fluctua ...

The International Conference on Polygeneration (ICP) have established as a highly reputed conference series for leading scholars in the field of energy conversion with more than one form and its re...

Graphene nanosheet devices have attracted significant interest in transistor and photodetector applications owing to photothermoelectric effects of graphene. However, their solar energy conversion ability has not been fully explored due to disadvantages of their transparency and zero gap semiconductor in this special field. Here, we propose the potential of graphene-carbon nanotube papers for energy conversion and storage under sunlight and heat. We show that macroscopic 3-dimensional structure of graphene-carbon nanotube papers provides advantages over graphene nanomaterials in converting large area power sources, namely solar and thermal energy into considerable current and voltage. We also report a graphene-carbon nanotube paper stack with p-n interfaces that incorporates a solar/thermal energy cell and a p–n junction capacitor, which can be simultaneously used for energy conversion and storage with a charge-storage capacity of 70.5 μC cm−2 at one sun intensity.

Electrohydrodynamic processing including electrospinning and electrospraying is suitable for depositing controllable structures in fiber or film form. In this work, the electrohydrodynamic approach was used to prepare poly(vinylidene fluoride)/polyaniline composite film. Scanning electron microscopic analysis was performed to show the morphology of the film on soft tissue paper. Self-poling of the film was found due to the high voltage application in the electrohydrodynamic process. The addition of polyaniline into PVDF improves the conductivity of the film significantly. Mechanoelectrical response of the film was demonstrated by measuring the open circuit voltage of the specimens under bending. The peak voltage generated is over 1.2 V due to the bending deformation of the film. The film has ultrafast response to the deformation. It is concluded that the film has multiple functions for mechanoelectrical energy conversion, vibration sensing, and structural integrity monitoring applications.

Energy generation using liquid movement over a graphene surface generally demands a very high rate of flow (e.g.∼100 ml min(-1)). In addition, a continuous flow of liquid is unable to generate a desired voltage, as it needs modification of the substrate such as development of nanopores and criss-cross network structures. Here, we report an ultra-low-cost yet highly efficient portable device for energy conversion, by exploiting the capillary flow of an electrolyte on a filter paper matrix in which a naturally deposited gradient of reduced graphene oxide is induced through chemical synthesis. In addition, the fibres and pores present in the paper offer a criss-cross network, acting as a natural splitter of a continuous flow into tiny droplets. Our methodology thus obviates the need for any elaborate procedure for pre-generation of droplets. Further, we fabricate the necessary electrodes on filter paper by simply scribing pencil tips on the same filter paper, which facilitates the necessary electrochemical reactions. Effectively, at the anode, electrons are released, which travel through the outer circuit for cation reduction at the cathode and deliver an electrical output (voltage/current), realizing the conversion of the chemical form of energy to the electrical form in the filter paper. An absorbent pad at the channel outlet ensures continuous flow of fresh solution in the device, resulting in an inexpensive platform for power generation over a prolonged period of time. A maximum current density of 325 mA cm(-2) and a maximum power density of 53 mW cm(-2) have been observed, which significantly outweigh the capabilities of other reported devices fabricated for similar purposes.

The performance of vacuum, slow and fast pyrolysis processes to transfer energy from the paper waste sludge (PWS) to liquid and solid products was compared. Paper waste sludges with low and high ash content (8.5 and 46.7 wt.%) were converted under optimised conditions for temperature and pellet size to maximise both product yields and energy content. Comparison of the gross energy conversions, as a combination of the bio-oil/tarry phase and char (ECsum), revealed that the fast pyrolysis performance was between 18.5% and 20.1% higher for the low ash PWS, and 18.4% and 36.5% higher for high ash PWS, when compared to the slow and vacuum pyrolysis processes respectively. For both PWSs, this finding was mainly attributed to higher production of condensable organic compounds and lower water yields during FP. The low ash PWS chars, fast pyrolysis bio-oils and vacuum pyrolysis tarry phase products had high calorific values (∼18-23 MJ kg-1) making them promising for energy applications. Considering the low calorific values of the chars from alternative pyrolysis processes (∼4-7 MJ kg-1), the high ash PWS should rather be converted to fast pyrolysis bio-oil to maximise the recovery of usable energy products.

Flexible thermoelectric materials are presented with potential applications in electronic devices and energy conversion due to their convenient preparation, good flexibility, and various forms. However, as ductility is rarely observed in inorganic semiconductors and ceramic insulators, reports on applications of inorganic oxide materials in flexible thermoelectric materials are sparse. Here, we report a new method for the synthesis of a flexible Na1.4Co2O4 thermoelectric material based on Na1.4Co2O4 bulk materials, which are prepared by a self-flux method and painted on print paper. Seebeck coefficient and power factor of the obtained thermoelectric material are 78–102 μVK-1 and 159–223 μWm-1K-2, respectively, in a temperature range of 303–522 K, which are superior to those values of other conductive polymers and their compounds. More interestingly, the n-type Na1.4Co2O4 flexible material is obtained in the painting process at higher pressure with Seebeck coefficients of –109 to –183 μVK-1 in a temperature range of 303–522 K. The convenient preparation method of these novel flexible thermoelectric materials may be expanded to the synthesis of other flexible thermoelectric materials, which will be the focus of future work.

Along with the chic fad energy industry field, the graphene application in energy conversion and management does bring about some benefits in terms of the energy transfer and storage development, the achievement it exerts on the multifaceted innovate approaches. Both current and previous studies on energy conversion, energy storage and energy transfer development, many research results are sufficient to show that all graphene products including graphene paper, film, foam and fiber have a significant role in improving performance. In the energy conversion research on the graphene paper, it has been recently demonstrated that putting the graphene into triboelectric nanogenerators practice possesses higher output performance than traditional generator, which has a maximum strain as large as 200% without evident degradation of the electrical properties. In terms of energy transfer, the graphene fiber application on the battery can significantly increase the charge and discharge rates with enhanced storage capacity of 763 F g−1. On the energy storage research, the graphene foam can enhance a high density of solar thermal storage up to 269.8 kJ kg−1 for long-term. Nano-graphene and graphene coating provide feasibility for the miniaturization of energy storage equipment which inspired the possibility for portable and foldable devices. The work done in this paper can effectively help promote the application of graphene in energy field. Based on our work, the researchers can choose graphene products (graphene paper, graphene film, graphene foam or graphene fiber) efficiently according to the research object in the future.

This paper investigates the thermochemical characteristics of date palm fronds (DPFs) to use as feedstock for different energy conversion processes. The proximate analysis, ultimate analysis, calorific value measurements, and elemental content measurements were carried out using some quantitative and qualitative techniques. At later stage, the gasification of DPFs was carried out in an externally hot gasifier system. The effect of gasification temperature and biomass particle size on gas composition and heating value of producer gas was investigated. The results showed that the thermochemical characteristics of DPFs were comparable with other biomass materials reported in the past literature. The gasification trials of the biomass revealed that temperature has a significant effect on gas composition, especially H2 and CO contents. The high temperature yielded high H2 and CO concentrations in the product gas. A good quality gas composition (in terms of H2, CO, CH4, and CO2 contents) was obtained from bigger particle sizes as compared to smaller sizes. The thermochemical characteristics of DPFs and gasification results showed that DPF feedstock is comparable with other conventional biomass for production of energy through appropriate thermochemical technologies.

Sun drying is popularly used in Lombok to dry food items including jackfruitDodolbecause it is easy and cheap. This type of drying has a weakness, which is very weather dependent. When it is cloudy or rainy, the drying process will stop, which will affect the income level of the jackfruitDodolbusiness. To overcome this, it is done through the application of a dryer with rice husk energy. Rice husks can be an alternative energy in drying process because they are easy to obtain and cheap. To make rice husks as drying energy, it can be done through an energy conversion process using a heat exchanger that is placed in a furnace. Tests were carried out in the drying process to produce a dry product of 5 kg of jackfruitDodol. The drying temperature is obtained from the result of the energy conversion process between burning rice husks in a furnace with environmental air flowing in the heat exchanger pipe. The resulting hot air flows into the drying chamber. This makes the product more hygienic and drying process can be all the time. The implication of the application of the rice husk energy dryer is to increase the jackfruitDodolbusiness income. This dryer provides a return on investment (ROI) rate of 304.48% with the break-even point (BEP) occurring at 0.2778 years or 3.3336 months. This means k Dodolis feasible.

Based on the energy and environmental audit, analysis of material flows, energy conversion, emissions into atmosphere and lithosphere in the production of instant coffee was carried out.To raise energy efficiency and reduce environmental burden, innovative flow diagrams and equipment for waste processing and production of new coffee products have been developed.Experimental modeling was carried out: kinetics of microwave extraction of water-soluble substances and oil from coffee slurry; hydraulics of the extractant flow through cassettes of the microwave extractor. The experimental data were summarized in the form of a criterion equation.As a result of experimental modeling of the extraction kinetics, it was found that the duration of the process in a microwave field is approximately 20 times less than in a thermostat. The microwave field affects the extraction rate to a greater extent than the process temperature. The growth of microwave power results in a more than the two-fold rise of the yield of extractives from a coffee slurry.Specification of the microwave oil extractor was defined. The extractor sample was tested at a specific power of 180...240 W/kg in the mode of boiling extractant. Ethanol (93...96 % concentration) was used as an extractant. As a result of the tests, a high-quality coffee oil was obtained. It is characterized by a pronounced aroma, coffee taste and an intense dark brown color.Flow diagram of pre-extraction of coffee from slurry was worked out. Additional extraction of water-soluble extractive substances from coffee slurry increased the extract yield by 10...12 %. The temperature regime of extraction was significantly reduced plus duration and energy intensity of the process were reduced.An innovative flow diagram has been developed for the production of liquid coffee concentrate as a basis for coffee-based drinks ready for immediate use. The concentration of solids is 50...65 %, На основе энергетического и экологического аудита проведен анализ материальных потоков, конверсии энергии, выбросов в атмосферу и литосферу при производстве растворимого кофе.Для повышения энергоэффективности, снижения экологической нагрузки разработаны инновационные технологические схемы и оборудование по переработке отходов и производству новых кофейных продуктов.Проведено экспериментальное моделирование: кинетики микроволнового экстрагирования водорастворимых веществ и масла из кофейного шлама; гидравлики течения экстрагента через кассеты микроволнового экстрактора. Экспериментальные данные обобщены в виде критериального уравнения.В результате экспериментального моделирования кинетики экстрагирования установлено, что продолжительность процесса в микроволновом поле приблизительно в 20 раз меньше, чем в термостате. Действие микроволнового поля влияет на скорость экстрагирования в большей мере, чем температура процесса. Повышение мощности микроволновой энергии повышает выход экстрактивных веществ из кофейного шлама более чем в два раза.Определены технические характеристики микроволнового экстрактора масла. Испытания образца экстрактора проводились при удельной мощности 180…240 Вт/кг в режиме кипения экстрагента. В качестве экстрагента использовался этанол (концентрация 93…96 %). В результате испытаний получено качественное кофейное масло, которое характеризуется выраженным ароматом и вкусом кофе и интенсивной темно-коричневой окраской.Разработана технологическая схема предэкстрагирования кофе из шлама. Дополнительное извлечение из шлама кофе водорастворимых экстрактивных веществ, повышает выход экстракта на 10…12 %. Существенно снижен температурный режим экстрагирования, уменьшена продолжительность и энергоемкость процесса.Разработана инновационная технологическая схема производства жидкого концентрата кофе – основы для напитков на базе кофе, готовых к немедленному употреблению. Концентрация сухих веществ составляет 50…65 %, На основі енергетичного й екологічного аудиту проведено аналіз матеріальних потоків, конверсії енергії, викидів в атмосферу й літосферу при виробництві розчинної кави.Для підвищення енергоефективності, зниження екологічного навантаження розроблені інноваційні технологічні схеми й устаткування по переробці відходів і виробництву нових кавових продуктів.Проведено експериментальне моделювання: кінетики мікрохвильового екстрагування водорозчинних речовин і масла з кавового шламу; гідравліки плину экстрагента через касети мікрохвильового екстрактора. Експериментальні дані узагальнені у вигляді критериального рівняння.У результаті експериментального моделювання кінетики екстрагування встановлено, що тривалість процесу в мікрохвильовому полі приблизно в 20 разів менше, ніж у термостаті. Дія мікрохвильового поля впливає на швидкість екстрагування більшою мірою, чим температура процесу. Підвищення потужності мікрохвильової енергії підвищує вихід екстрактивних речовин з кавового шламу більш ніж у два рази.Визначено технічні характеристики мікрохвильового екстрактора масла. Випробування зразка екстрактора проводилися при питомій потужності 180…240 Вт/кг у режимі кипіння екстрагенту. У якості екстрагенту використовувався етанол (концентрація 93...96 %). У результаті випробувань отримане якісне кавове масло, що характеризується вираженим ароматом і смаком кави й інтенсивним темно-коричневим фарбуванням.Розроблено технологічну схему передекстрагування кави зі шламу. Додатковий витяг зі шламу кави водорозчинних екстрактивних речовин, підвищує вихід екстракту на 10...12 %. Істотно знижено температурний режим екстрагування, зменшені тривалість і енергоємність процесу.Розроблено інноваційну технологічну схему виробництва рідкого концентрату кави – основи для напоїв на базі кави, готових до безпосереднього вживання. Концентрація сухих речовин становить 50...65 %

Interfacial solar steam generation is a highly efficient and sustainable technology for clean water production and wastewater treatment. Although great progress has been achieved in improving evaporation rate and energy efficiency, it's still challenging to fully eliminate the energy loss to the surrounding environment during solar steam generation. To achieve this, a novel heatsink‐like evaporator (HSE) is developed herein. During solar evaporation, the temperature on the top solar evaporation surface can be regulated by the fin structures of the HSE. For the evaporators with 5 to 7 heatsink fins, the temperature of the solar evaporation surface is decreased to be lower than the ambient temperature, which fully eliminates the radiation, convection, and conduction heat losses, leading to the absolute cold evaporation over the entire evaporator under 1.0 sun irradiation. As a result, massive energy (4.26 W), which is over 170% of the received light energy, is harvested from the environment due to the temperature deficit, significantly enhancing the energy efficiency of solar steam generation. An extremely high evaporation rate of 4.10 kg m−2 h−1 is realized with a 6‐fin photothermal HSE, corresponding to an energy conversion efficiency far beyond the theoretical limit, assuming 100% light‐to‐vapor energy conversion., A heat‐sink like photothermal evaporator is designed and fabricated to realize fully cold solar evaporation under one sun irradiation with zero energy loss and massive energy gain (equivalent to 170% of the incident light energy) from the environment. An extremely high evaporation rate of 4.10 kg m−2 h−1 with corresponding energy efficiency far beyond the theoretical limit is achieved.

Energy cost contributes to the second largest portion of the starch-processing plants’ expenditure. Therefore, to improve energy efficiencies, CHP systems installed in cassava starch plants are considered. Hence, their energy conversions and efficiencies are investigated. Where, the structure of the plant is modeled, the factors of biogas, power, heat and the biogas distribution ratio are focused; the relationships among those factors are resolved by establishing formulas based on theoretical analysis. Results show: the minimum demand of biogas for 1 t starch product is 134.8 m3, which can produce 704.7–875.6 MJ of electric energy and total 1311.0 MJ of heat for starch production by a CHP-boiler system. The steam produced there can fully satisfy the heat demand under the three strategies, while a minority of excess electricity is available under the strategy 3. The total energy efficiencies of the CHP-boiler system are 70.6%, 70.1% and 67.1% corresponding to the three strategies; those are 8.4%–11.9% more than the efficiency of 58.7% by the original system. The total reduction of CO2 emissions is 2017.1–2508.3t/a for a 200 t/d cassava starch plant using CHP-boiler system; which investment costs 27.24 million CNY in total, and will be pay back in 3.18 years.

Rape straw, as a typical residue from agriculture, was recycled to produce bio-oil via vacuum pyrolysis. The energy conversion rate (ECR) of biomass pyrolysis was proposed to take into acco...