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1.
The environmental impact of hydrogen production in a 2-step fermentation process from potato steam peels was identified. Based on the ISO 14040, ISO 14044, ecoinvent data base and SimaPro 7.1 software, a life cycle inventory analysis was performed. Reflecting the current state of process development, the LCA shows an impact of 4.3 points (pts) which is at least 5.7 times higher than the selected reference technologies regarded as state-of-the-art. Over half (53.5%) of the environmental impact is generated by the use of phosphate in the fermentation processes. A sensitivity analysis shows a potential impact reduction of 65.8% due to recirculation of sewage or reduction of buffer concentration. The analysis also demonstrates that the production of the process ingredients cause 98.3% of the environmental impact. The impact of the process itself is 0.07 pts which is up to 10 times lower than the reference technologies.  相似文献   

2.
《Journal of Cleaner Production》2007,15(13-14):1271-1286
The analysis of industrial energy usage indicates that low temperature processes (20  200 °C) are used in nearly all industrial sectors. In principle there is the potential to use solar thermal energy in these lower temperature processes thus, reducing the environmental impact of burning fossil fuels. Using the model of an Austrian dairy plant, this research investigated the potential for, and the economic viability of, using solar energy heat processes in industry.Some industrial sectors such as food, chemistry, plastic processing, textile industry, building materials industry and business establishments can be identified as potential sectors for the application of solar energy heat processes. When assessing the (economic) feasibility of solar thermal energy, the investigation of these industries’ energy systems has to focus on an integrated analysis of cooling and heating demands and to take into account competing technologies. Amongst these are heat integration, cogeneration, new technologies and heat pumps. Pinch analysis was used to investigate industrial energy systems and heat integration possibilities and proved to be a viable tool. Working from the basis of energy balances, Sankey diagrams, pinch analysis and environmental cost accounting, a newly developed investigation tool was applied in the case study of an Austrian dairy plant. This enabled a fast optimization of the system. Two different options for the integration of solar thermal energy into the production line were calculated, option 1 with a solar field of 1000 m2 and option 2 with a solar field of 1500 m2. Natural gas savings of 85,000 for option 1 and 109,000 m3/a for option 2 can be achieved, resulting in a reduction of 170 tons of CO2 per year, or 218 tons for options 1 and 2 respectively. Based upon option 1, return on investment is realised after less than three years of implementation. This research thus, indicates promising technical and economical feasibility of using solar thermal energy for industrial processes and provides an important step towards sustainable zero emission production in industry.  相似文献   

3.
4.
Numerous different bioreactor systems are applied for hydrogen production by dark fermentation. Thermophilic fermentations are gaining an increased interest due to the high hydrogen yields associated with them. In order to reach the best thermophilic fermentation system, 2 types of bioreactors, a trickling bed and a fluidized bed system, were constructed and operated under similar conditions. Both systems were designed to meet the requirements of thermophilic fermentations, such as reduction of hydrogen partial pressure, system immanence as its best as well as increasing cell densities. For comparing the 2 systems, the extreme thermophilic organism Caldicellulosiruptor owensensis OLT and a glucose-containing medium were employed. Parameters like hydraulic retention time, glucose concentration and stripping gas amount were varied. Each bioreactor system exhibited certain advantages; the trickling bed system enabled yields close to 3 mol-H2 (mol-glucose)?1 and productivities of 0.2 L L?1 h?1, but the application of stripping gas seemed to be obligatory. The fermentations in the fluidized bed system were characterized by slightly higher productivities (0.25 L L?1 h?1), but generally lower yields. However, operation of this system without stripping gas was possible.  相似文献   

5.
The empirical evidence of decline in ecosystem services (ES) over the last century has reinforced the call for ES quantification, monitoring and valuation. Usually, only provisioning ES are marketable and accounted for, whereas regulating, supporting and cultural ES are typically non-marketable and overlooked in connection with land-use or management decisions. The objective of this study was to quantify and value total ES (marketable and non-marketable) of diverse production systems and management intensities in Denmark to provide a basis for decisions based on economic values. The production systems were conventional wheat (Cwheat), a combined food and energy (CFE) production system and beech forest. Marketable (provisioning ES) and non-marketable ES (supporting, regulating and cultural) ES were quantified by dedicated on-site field measurements supplemented by literature data. The value of total ES was highest in CFE (US$ 3142 ha−1 yr−1) followed by Cwheat (US$ 2767 ha−1 yr−1) and beech forest (US$ 2328 ha−1 yr−1). As the production system shifted from Cwheat - CFE–beech, the marketable ES share decreased from 88% to 75% in CFE and 55% in beech whereas the non-marketable ES share increased to 12%, 25% and 45% of total ES in Cwheat, CFE and beech respectively, demonstrating production system and management effects on ES values. Total ES valuation, disintegrated into marketable and non-marketable share is a potential way forward to value ES and ‘tune’ our production systems for enhanced ES provision. Such monetary valuation can be used by policy makers and land managers as a tool to assess ES value and monitor the sustained flow of ES. The application of ES-based valuation for land management can enhance ES provision for maintaining the productive capacity of the land without depending on the external fossil-based fertilizer and chemical input.  相似文献   

6.
Generally, a refinery complex consists of process system and utility system. Process system not only produces liquefied petroleum gas, gasoline, diesel and so on, but also some byproducts, such as fuel gas and residual fuel oil, which supply utility system as fuel. The utility system converts fuel gas and fuel oil to high pressure or medium pressure steam and electricity to meet the energy demand of the process system. A novel approach to the integration of the process system and utility system for better energy utilization is presented in this paper. A plant-wide multi-period planning mathematical model is proposed and three improvements are identified. First, the process unit energy-consumed model is reformulated, because energy consumed by a unit not only relates the throughput of the unit, but also varies with the operation modes of the unit and season. Second, The MILP (Mixed Integer linear Programming) model of utility system is embedded in the plant-wide model to gain the overall optimization and for better energy efficiency. Third, steam, fuel oil and fuel gas are balanced in the whole plant. Finally, the proposed approach was used in a real industrial example to determine the optimal mass and energy flow and some important results have been obtained and are presented.  相似文献   

7.
卢建宏  李卓  孙驰贺  付乾  李俊  张亮  廖强  朱恂 《中国环境科学》2019,39(10):4157-4163
区别于传统的稀释或加缓冲剂调节pH值的方法,本文提出采用微生物电解池(MEC)电调控暗发酵尾液pH值,并进一步采用微生物电合成系统(MES)降解废液产甲烷.结果表明,在MEC处理产氢暗发酵尾液过程中,伴随着阴极侧氢气的产生,暗发酵尾液中大量H+被消耗,溶液pH值从4.5升高到8.7;随后在MES中,产氢发酵尾液中有机物被进一步降解产生甲烷,其平均产甲烷速率达到4.5mmol/(L·d),且在21d内化学需氧量(COD)去除率达到89%,远优于没有经过pH调控的产氢发酵尾液MES中的产甲烷性能.  相似文献   

8.
Many environmental and social problems emerged from our modern production and consumption habits are comparable with the symptoms of physical obesity. Based on this metaphor, effective approaches in obesity treatment can serve as a good reference in order to respond to over-consumption problems. Instead of stressing consumers to change their behaviours, we can attract them by means of providing appropriately designed PSS offers and giving them the opportunities to become aware of better alternatives. Successful examples seem to document support for the hypothesis that, ‘the multidimensional and dynamic approaches are the most promising diet solutions, which can lead to a leaner production and consumption figure.’  相似文献   

9.
Government interventions have been identified as important for energy systems change, because they can either facilitate or hinder transitions toward more sustainable energy systems. This article analyses how bioenergy options have been framed in Finnish policy strategies and how the framing has changed over time. The empirical material includes the content of 15 government programmes and nine national energy/climate strategies. On the basis of this assessment, both the link between bioenergy framings in strategies and the actual transformation of Finnish bioenergy systems are explored.On the basis of bioenergy framings, the development of energy policy can be divided into three phases: support for domestic energy sources in 1979-1991, support for wood- and industry-based bioenergy in 1992-1998, and diversified bioenergy in the context of climate change in 1999-2010. For two decades, primarily wood-based bioenergy was supported despite alternative technological developments occurring elsewhere. After the turn of the millennium, the importance of climate policy increased and alternative bioenergy sources were raised on the government policy agenda, also resulting in some new policy instruments. Rather than adopting a visionary outlook to guide system transformation, climate and energy policy has strengthened those technological options that have been selected elsewhere. If public policies are to enhance the shift toward low-carbon, sustainable energy systems, they would need to be more comprehensive, be more consistent over time, and emphasise energy use more.  相似文献   

10.
《Journal of Cleaner Production》2006,14(12-13):1121-1138
Many firms are embracing the environmental challenge by implementing incremental changes in their production systems. Nevertheless, radical innovations are also important for achieving sustainability goals. This paper focuses on the technology strategies leading to radical innovations in aluminium production systems. It conceptualizes the radical nature of innovations, and develops a framework for analysing the technology strategies of two aluminium smelters, Aluminium Delfzijl in The Netherlands and Hydro Aluminium in Norway. From the analysis, policy instruments are proposed for a transition towards sustainable aluminium production.  相似文献   

11.
The comparison of the environmental performance of contrasting agricultural production systems using life cycle assessment (LCA) requires very specific data for each production mode, especially for direct emissions on the farm. In a case study of pig production, three contrasting production scenarios were defined: conventional good agricultural practice (GAP), organic agriculture (OA), and red label (RL). An expert panel produced methods for the estimation of emissions for key-processes of these scenarios. Clear differences were obtained for these emissions between the three scenarios. Finally, the summation of the main emissions for the entire life cycle allowed the identification of weak points for each scenario, which can be explained by the differences obtained for the emissions of the key-processes studied.  相似文献   

12.
The aim of this paper is to examine the environmental consequences of beef meat production in the EU, using a life cycle approach. Four beef production systems were studied – three from intensively reared dairy calves and one from suckler herds. According to the results of the analysis, the contributions from the production of 1 kg beef meat (slaughter weight) to global warming, acidification, eutrophication, land use and non-renewable energy use were lower for beef from dairy calves than from suckler herds (16.0–19.9 versus 27.3 kg CO2e, 101–173 versus 210 g SO2e, 622–1140 versus 1651 g NO3e, 16.5–22.7 versus 42.9 m2year, and 41.3–48.2 versus 59.2 MJ, respectively). The breakdown analysis helped identify the key areas in the “cradle to farm gate” beef production system where sustainable management strategies are needed to improve environmental performance. The study also included a sensitivity analysis to preliminarily estimate GHG emissions from beef production systems if land opportunity cost and land use change related to grazing and feed crop production for beef were taken into account. If so, the contribution from the production of 1 kg beef to global warming would increase by a factor of 3.1–3.9, based on a depreciation period of 20 years. This highlights the importance of taking into account the impacts of land use in assessing the environmental impacts of livestock production.  相似文献   

13.
The tapioca processing industry is considered to be one of the largest food processing industrial sectors in Thailand. However, the growth of the tapioca starch industry has resulted in heavy water pollution as it generates large amount of solid waste and wastewater with high organic content. This study explores the applicability of clean technology options to improve the environmental performance of tapioca starch-processing plants in Thailand. Eight Tapioca starch plants were selected for an exclusive analysis of the dynamics of clean technology development and adoption. Proposed options mainly involve water reduction and energy conservation. These include reuse and recycling of water, technology modification in the production process, and use of biogas to substitute fuel oil for burners. Implementation of these proposed alternatives to real companies shows that the reduction of starch loss, and water and fuel cost savings can be achieved.  相似文献   

14.
The central role played by livestock in the livelihoods of rural households in the developing world is seldom fully appreciated by policy makers, development agencies and donors. Knowledge gaps in the geographic distribution and environmental determinants of farming systems, especially if viewed through the livestock lens, compound this problem. We have produced a map of pastoral, agro-pastoral and mixed farming systems across Eastern Africa, by analysing datasets collected in the framework of livelihood analysis. Input data were gathered between 2000 and 2007 by various emergency and development agencies for Djibouti, Eritrea, Kenya, Somalia, Uganda and parts of Ethiopia and Sudan. A quantitative definition of the production systems is adopted, based on the ratio of livestock- to crop-derived income. The resulting livelihood-based map of livestock production systems was compared through correspondence analysis to an alternative livestock production systems map, produced independently from environmental data. Convergence between the two mapping approaches was evident. The geographic distribution of the livestock production systems was also modelled using multivariate analysis of remotely sensed and other geospatial datasets. Models show high statistical accuracy, and were thus used to fill the gaps in the observed distribution of livestock production systems. Finally, selected environmental factors underpinning the systems (agro-climatology, human and livestock populations and land cover) were analysed in detail, enabling the livestock production systems to be characterized in terms of them. The regional scope of the map, as well as its direct link with a vast amount of livelihood information, render it a valuable tool for a range of development and research applications, including those related to global change.  相似文献   

15.
The Intergovernmental Panel on Climate Change(IPCC) recognises the pivotal role of renewable energies in the future energy system and the achievement of the zero-emission target. The implementation of renewables should provide major opportunities and enable a more secure and decentralised energy supply system. Renewable fuels provide long-term solutions for the transport sector, particularly for applications where fuels with high energy density are required. In addition, it helps reducing the ca...  相似文献   

16.
This paper originated as a part of a comprehensive research project designed to develop ecologically sustainable, environmentally friendly, resource- and energy-saving industrial process technology for the production of a wide class of phosphorus containing substances. The essential feature of the research was designed for the replacement of tubular heat exchangers with Plate heat exchangers (PHEs) and for the installation of these units in new locations in the processes to optimally improve energy efficiency and to prevent pollution. Despite the severe operating conditions in the production of phosphoric acid PHEs of various designs find the application in these processes. For such a corrosive environment as a phosphoric acid production plant, the Hastelloy G30 alloy is used as the material for the plates and synthetic rubber EPDM is used as the material for inter-plate gaskets. The analysis of the data shows, that using mixed groupings of plates in the unit allows one to obtain optimal solutions. The simulation of barometric mixing condenser recycled water cooling with plate heat exchanger shows the possibility of an application which minimizes the waste water pollution by closing the condenser cooling water circuit. Software was developed for calculations of units working both with liquid and phase changing streams.  相似文献   

17.
Production of upland rice under shifting cultivation system is an important economic activity in the mountainous areas of northern Vietnam. A comparative study of two districts with differential market access and population pressure was conducted to highlight the effect of these variables on upland rice systems in northern Vietnam. Farmers in the district with a greater population pressure have a shorter cropping and a shorter fallowing cycle than in the district with lower population pressure. Farmers reported a high incidence of food shortage in both districts. Income from livestock and wages are important for food purchases, especially in the district with a better access to market. Even in these upland districts, access to lowland fields is a critical determinant of food security.  相似文献   

18.
In new product development, the ability to integrate different dimensions of sustainability at a value chain level is still a complex, problematic goal. As product-service approaches are increasingly enabling the introduction of more sustainable paths, this paper describes the authors' experience thus far when building insights into conditions for the implementation of integrated solutions in a process of co-development and testing in real life conditions, which are driven by a social need focusing on food for people with reduced access. Throughout this process, which brought together producers, consumers and other stakeholders to design and test industrialised, sustainable solutions, empirical evidence demonstrates feasibility and usefulness of the approach and insight into the conditions for implementing interactive, comprehensive multi-stakeholder processes in real life situations. In addition, results show that the delivery of innovative solutions enabled to offer social added value, economic profits and environmental improvements under specific experimental conditions.  相似文献   

19.
A Life Cycle Assessment (LCA) was performed to analyze environmental consequences of different pear production chains in terms of fossil energy use and greenhouse gas (GHG) emission in China. The assessment identified hotspots that contributed significantly to the environmental impacts of pear production from the cradle to the point of sale. The results showed that GHG emissions and fossil energy use varied in the different production chains because the environmental performance does not associate with the farming systems (i.e. organic vs. conventional), but is co-determined by farm topography and thus machinery use, by market demands to seasonality of products and thus the need for storage, and by local farming practices including manure management. The LCA could be used as a tool to guide selections of agricultural inputs with the aim of reducing environmental impacts. The results of the LCA analysis indicate that a list of choices are available to reduce energy use and GHG emission in the pear production chain, namely substitution of the traditional storage systems by an efficiently controlled atmosphere storage system, using manure for biogas production, conversion from the conventional farming to organic farming, and reduction of mechanical cultivation.  相似文献   

20.
Crop derived biofuels such as (bio)ethanol are increasingly applied for automotive purposes. They have, however, a relatively low efficiency in converting solar energy into automotive power. The outcome of life cycle studies concerning ethanol as to fossil fuel inputs and greenhouse gas emissions associated with such inputs depend strongly on the assumptions made regarding e.g. allocation, inclusion of upstream processes and estimates of environmentally relevant in- and outputs. Peer reviewed studies suggest that CO2 emissions linked to life cycle fossil fuel input are typically about 2.1–3.0 kg CO2 kg−1 starch-derived ethanol. When biofuel production involves agricultural practices that are common in Europe there are net losses of carbon from soil and emissions of the greenhouse gas N2O. Dependent on choices regarding allocation, they may, for wheat (starch) be in the order of 0.6–2.5 kg CO2 equivalent kg−1 of ethanol. This makes ethanol derived from starch, or sugar crops, in Europe still less attractive for mitigating climate change. In case of wheat, changes in agricultural practice may reduce or reverse carbon loss from soils. When biofuel production from crops leads to expansion of cropland while reducing forested areas or grassland, added impetus will be given to climate change.  相似文献   

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