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1.
Alcohol ethoxylates surfactants are produced via ethoxylation of fatty alcohol (FA) with ethylene oxide. The source of FA could be either palm kernel oil (PKO) or petrochemicals. The study aimed to compare the potential environmental impacts for PKO‐derived FA (PKO‐FA) and petrochemicals‐derived FA (petro‐FA). Cradle‐to‐gate life cycle assessment has been performed for this purpose because it enables understanding of the impacts across the life cycle and impact categories. The results show that petro‐FA has overall lower average greenhouse gas (GHG) emissions (~2.97 kg CO2e) compared to PKO‐FA (~5.27 kg CO2e). (1) The practices in land use change for palm plantations, (2) end‐of‐life treatment for palm oil mill wastewater effluent and (3) end‐of‐life treatment for empty fruit bunches are the three determining factors for the environmental impacts of PKO‐FA. For petro‐FA, n‐olefin production, ethylene production and thermal energy production are the main factors. We found the judicious decisions on land use change, effluent treatment and solid waste treatment are key to making PKO‐FA environmentally sustainable. The sensitivity results show the broad distribution for PKO‐FA due to varying practices in palm cultivation. PKO‐FA has higher impacts on average for 12 out of 18 impact categories evaluated. For the base case, when accounted for uncertainty and sensitivity analyses results, the study finds that marine eutrophication, agricultural land occupation, natural land occupation, fossil depletion, particulate matter formation, and water depletion are affected by the sourcing decision. The sourcing of FA involves trade‐offs and depends on the specific practices through the PKO life cycle from an environmental impact perspective.  相似文献   

2.
Pyrolysis is seen as promising to recycle sorted mixed plastic waste and reduce the global warming impact of the linear plastic economy. However, in Germany, the benefits of pyrolysis are questioned due to a lack of transparent data and regional life cycle assessments. Here, we provide a life cycle assessment of pyrolysis with caustic soda or lime compared to waste incineration with energy recovery. The life cycle assessment evaluates the treatment of 1 kg of Germany's sorted mixed plastic waste while providing full data transparency of the processes. Our results show a reduction in global warming impacts of 60 % to 94 %, considering today's and the future German energy system.  相似文献   

3.
BACKGROUND: The forest products industry produces valuable industrial chemicals, wood products, and consumer goods, but is also responsible for the emission of significant quantities of hazardous air pollutants. Although many air pollution control options are available, little is known about the overall environmental impacts of implementing each option. Therefore, a life cycle assessment (LCA) was conducted to compare energy and raw material inputs, air emissions, and environmental impacts associated with construction and operation of two air pollution control systems: regenerative thermal oxidation (RTO) with wet scrubbing and photocatalytic oxidation (PCO) with biofiltration. RESULTS: LCA results indicated that environmental impacts to resource depletion, photochemical oxidant formation, and acidification were 20% higher for the use of a RTO‐scrubber than for the PCO‐biofilter. In addition, at least 25% of the RTO impacts were due to infrastructure requirements. However, the PCO‐biofilter system was responsible for more environmental impact in categories of global warming and human toxicity, because of the packing materials required and the electricity use for the PCO reactor. CONCLUSIONS: The PCO‐biofilter system could be a promising, environmentally‐friendly alternative to traditional RTO devices, provided that this system is modified to decrease resource and energy demands. Copyright © 2008 Society of Chemical Industry  相似文献   

4.
Life cycle impact assessment (LCIA) is one of basic steps in life cycle assessment methodology (LCA). This paper presents a comparative study of the LCIA of different life cycle inventories (LCI) for EU cements. The analysis unit used is the manufacture of 1 kg of cement, from “cradle to gate”. The impact categories considered are those resulting from the manufacture of cement and include greenhouse effects, acidification, eutrophication and summer and winter smog, amongst others.The results of the study highlighted some inconsistencies in existing inventories. As for the LCIA, the main environmental interventions related to cement manufacture were classified and characterised and their effect on different impact categories analysed. Differences observed in evaluation of the impact of cement type were essentially related to their clinker content.  相似文献   

5.
In this study, life cycle assessment of oxygen-18 by using cryogenic distillation of oxygen is performed using SimaPro 8.3 software. Life cycle assessment is performed to understand the environmental profile and hotspots of this process in order to be used in design and development. Simulation of oxygen-18 process is executed by Hysys software, and the required inputs and outputs for inventory of life cycle were acquired. By doing life cycle assessment and considering achieved results after characterization and normalization of inventory data it has been investigated that in the majority of environmental impacts electricity consumption has a huge contribution relative to other parts of the system like liquefied oxygen production from air separation unit, required facilities for air separation and oxygen-18 units, and needed transportation. Also, among 17 impact categories investigated in ReCiPe impact assessment method, fossil depletion, climate change (human health), particulate matter formation, climate change (ecosystem), human toxicity, and metal depletion have the most contribution in entire environmental loads respectively. Furthermore, sensitivity analysis showed that changing life cycle impact assessment method from ReCiPe to IMPACT 2002 + has no significant effect on acquired results and results are confident. In addition, assumption of market for depleted oxygen from heavy isotopes which is withdrawn from top of distillation columns showed some positive effects compared to first case and environmental impacts resulted from liquefied oxygen production (feed) reduced but because of huge contribution of electricity consumption compared to other sections, this positive effect has no remarkable influence on entire environmental loads of product system.  相似文献   

6.
A coating of Nylon 6,6 or 6,12 was used to improve the penetration resistance of ultra high molecular weight polyethylene (UHMWPE) fabric that would be potentially useful in the manufacture of flexible body armor against spike/knife threats. Quasi‐static test results for the spike penetrator showed a 77% and 86% improvement in the puncture resistance of Nylon 6,6 and Nylon 6,12 coated UHMWPE (respectively) over a neat fabric target of equivalent areal densities. Dynamic impact testing demonstrated dramatic improvement in the puncture resistance of nylon‐coated fabrics while only a slight improvement in stab resistance was observed comparing samples with equivalent areal densities. Photography of ruptured areas after quasi‐static testing revealed limited fiber motion or fiber stretching with no evidence of fiber pullout for nylon‐coated fabric samples in contrast to neat fabric. This suggests that there was a significant increase in energy absorption by nylon‐coated fabrics at impact. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40350.  相似文献   

7.
A mathematical model of a ported kiln for iron oxide pelletizing was developed to simulate the effects of under‐bed air injection on kiln fuel requirements and magnetite oxidation. A tanks‐in‐series model was used to set up material and energy balance equations for countercurrent flow of solids and gas through the kiln. The diffusion‐limited, shrinking core model was used for the magnetite oxidation reaction kinetics. The port air distribution in the model was adjusted by global optimization to minimize the fuel requirement. The simulation results show that magnetite oxidation may be completed in the kiln with significant fuel savings.  相似文献   

8.
M. Birch  J.E. Brocklehurst 《Carbon》1983,21(5):497-510
Repeated impact tests have been carried out on a wide range of polycrystalline graphites. Two modes of test were employed using centrally impacted rods and discs with the rods supported horizontally at their ends and the discs supported around the circumference. The resulting impact endurance curves for all the different graphites under repeated impacts of constant energy were found to have a substantially common shape in both the disc and the rod tests. The absolute levels of the endurance curves differ considerably and correlate well with other mechanical properties of graphites, in particular the strain energy density at failure in bend. Measurement of impact forces on the single impact failure of graphite rods supports this correlation by showing that the dynamic stresses generated at failure in a single impact are the same as the corresponding static 3-point bend strengths in the same test mode. Measurement of impact forces at energies less than those required to cause failure in a single impact show that the fraction of energy absorbed as specimen strain energy is dependent on specimen size and shape but is not very sensitive to impact energy. A fracture mechanics model based on incremental crack growth and previously used to interpret stress-cycling fatigue data for graphite is proposed to describe also the endurance of polycrystalline graphite under repeated impacts. The model describes available experimental data obtained under both impact and fatigue conditions. On this model, the difference between the two cyclic stressing modes is the rate of crack growth per stress cycle, this being greater under repeated impacts than under fatigue cycles of the same stress amplitude.  相似文献   

9.
采用生命周期评价方法对硼铁矿火法分离过程进行了环境影响评价研究. 结果表明,开采加工1万t硼铁矿对气候变化、酸化、光化学臭氧形成、水体富营养化和人体毒性的影响分别为1.45′107 kg CO2当量,3.61′104 kg SO2当量,7.16′102 kg C2H4当量,30.41 kg PO43-当量和2.43′104 kg C6H4Cl2当量,对矿产资源和化石能源消耗的影响分别为7.72′103 kg Sb当量和3.68′10-1 kg Sb当量,水消耗为1.24′105 m3;对土地占用的影响为7.98′106 kg固体废物;各生产环节中,原材料生产环节对水资源消耗和土地占用的影响最大,高炉冶炼环节对气候变化、光化学臭氧形成、水体富营养化、矿产资源和能源消耗的影响最大,硼砂生产环节对酸化、人体毒性的影响最大;除对资源、能源的消耗和土地占用的影响外,能源产品生产过程带入系统的环境影响均高于生产过程.  相似文献   

10.
A major issue associated with munitions containing red phosphorus is that, during storage, red phosphorus can react, in the presence of moisture and air, to form a mixture of corrosive phosphorus acids and the toxic gas phosphine. This has raised serious concerns relating to the health and safety of personnel handling these munitions. This paper details the studies undertaken to assess the suitability of a chemically impregnated activated carbon cloth (phosphine getter material – PGM) for the static adsorption of phosphine evolved from munitions containing red phosphorus and its effective mitigation of phosphine present in both ammunition container assemblies and within the main body of munitions of this type. Laboratory assessment of PGM was undertaken along with real‐life ammunition container assembly trials covering several munitions containing red phosphorus and accelerated ageing trials using modified countermeasure cartridges. Reaction products formed from the reaction of phosphine with chemical impregnates were studied using scanning electron microscopy (SEM) and energy dispersive X‐ray analysis (EDX). Aqueous extraction of the phosphine reacted PGM confirmed the presence of the acidic species orthophosphoric acid (H3PO4) and phosphorus acid (H3PO3).  相似文献   

11.
柯刚 《水泥工程》2012,(6):39-41
水泥用回转窑的大齿圈是回转窑的关键部件,也是生产制造控制中的重点、难点部件。结合10多条2500~6000t/d项目回转窑大齿圈制造、应用实践经验与教训,重点就大齿圈裂缝缺陷和凸台组织疏松、气孔缺陷的修复进行了详细介绍;同时对大齿圈的结构设计和制造工艺改进进行分析介绍。  相似文献   

12.
能源和化工系统的全生命周期评价和可持续性研究   总被引:3,自引:7,他引:3       下载免费PDF全文
在资源和能源日趋紧缺的背景下,开拓替代能源和新的化工产品技术路线势在必行。然而,目前对各种新技术方案的基础数据和系统分析比较薄弱,对产业布局和生态环境的长期影响有待深入研究。对近年来研究资源/能源化工复杂系统的建模、模拟、结构优化和系统集成问题的进展进行综述,运用过程系统投入产出分析的理论和方法,建立化工产品技术路线的全生命周期分析模型与集成的框架平台,研究资源、能源、技术、经济、环境等多因素综合优化评价问题。以煤气化合成气衍生的煤化工系统为基础案例,专门论述了在产品路线规划和过程合成中,集成优化、全生命周期评价和可持续性的研究进展。目标在于推进"技术-经济-环境-产业发展"多属性、多目标、多尺度系统集成的基础理论研究和技术创新。  相似文献   

13.
中国陶瓷热工技术和窑炉的发展水平与前景   总被引:2,自引:0,他引:2  
高力明 《中国陶瓷》2005,41(1):1-6,19
对20世纪最后20年我国的窑炉热工理论研究与技术开发做了一个回顾,在此基础上对陶瓷窑炉及其产业的发展水平和前景做了展望。将回顾的结果归纳成14个问题,逐一做了评述;然后指出我国已经形成了初具规模、技术水平较高、配套基本齐全的陶瓷窑炉产业,主要窑型—辊道窑、窑车式隧道窑和梭式窑均已达到或接近20世纪90年代国际先进水平。现在,我国的陶瓷窑炉产业不仅已经可以为国内的陶瓷行业提供成套的优质窑炉装备,而且还可为其他一些行业提供部分的工业炉装备,并已具有出口这些窑炉装备的能力。  相似文献   

14.
Organisations today face increasing environmental constraints, e.g. in the form of legal and customer requirements; the defence sector is no exception. There is a need to evaluate and limit environmental effects of defence activities and materiel. In this study we used quantitative Life Cycle Assessment (LCA) and a method for simplified LCA (the Material, Energy, Chemicals and Others (MECO) method) to assess the environmental impacts of a grenade. The aims of the study are to identify aspects in the grenade's life‐cycle that have the largest environmental impact, suggest improvement possibilities, make a comparison between different approaches for waste management of munitions, and to perform a demonstrative case for the application of LCA to munitions. Significant environmental aspects of the grenade's life‐cycle include use of metals, use of fossil fuels, and detonation outdoors. The study shows that an LCA can be used to analyse environmental impacts from munitions. The simplified LCA gave information that is complementary to the quantitative LCA. Copyright © 2005 Society of Chemical Industry  相似文献   

15.
潘弘  田华  王磊  孙钢 《玻璃》2022,49(2):48-52
蓄热室格子体是浮法窑炉重要的蓄热和排废设备,在窑炉全生命周期中,随着窑炉运行时间的延长,蓄热室格子孔会逐渐堵塞,堵塞严重时,影响助燃风的进入和烟气的排出,从而影响蓄热室的蓄热、排废、送风效果;影响火焰的燃烧和窑压的稳定,造成窑内热气流的负面变化,导致燃烧不完全、燃料的严重浪费,进而造成玻璃质量严重降低;因此,从新线投产就要做好蓄热室格子体全生命周期管理,重视蓄热室格子体的堵塞状态,及时疏通,维持蓄热室良好的畅通状态。建议从投产开始做好蓄热室全生命周期的管理。  相似文献   

16.
徐金福 《水泥工程》2015,28(3):41-42
如何延长回转窑窑口耐火材料使用周期是耐火材料管理中的难点和重点之一。以某水泥公司回转窑窑口耐火材料配置方案为例,分析了窑口耐火材料使用周期变短的诸多原因,提出了提高窑口耐火材料使用寿命的措施,主要包括优化窑口耐火材料设计和实施精细化施工方案等。  相似文献   

17.
During the last decades, authorities’ awareness on environmental and human health impact at national and international level has increased in the field of small arms ammunition containing lead and antimony. Thus, the evolution of environmental policies regarding production and use of heavy metals and their compounds, especially in EU countries, implied extensive studies on the environmental implications of 9×19 mm caliber ammunition use, especially in indoor shooting ranges. In this context, the paper describes the experimental studies performed on Pb‐containing conventional FMJ (full metal jacketed) ammunition and comparative measurements on new ammunition designed for training. The combustion products and residues from conventional Pb‐containing ammunition and Cu‐based “greener” ammunition were compared in terms of gaseous products, metal concentration in aerosols and metal concentrations in solid residues. Gas emissions and solid residues were measured for four different types of ammunitions. The results showed that the copper content of the residue is significantly higher in case of Cu‐containing composite bullets. For the ammunition equipped with Pb bullet, an important percentage of the Pb residue is generated by erosion of the exposed part of the bullet core. On the other hand, the ammunition containing Cu‐composite bullet generates large quantities of Cu residues, which have similar environmental impact and less impact on human health. Gas analysis indicated the presence of CO and NOx and, surprisingly, high concentrations of HCN, CH4, and NH3. Lower gas concentrations are obtained for the composite bullets due to an incomplete combustion of gun propellant.  相似文献   

18.
In this paper, two waste solvent technologies are presented as alternatives to the disposal of spent acetone-water mixtures.

In the first alternative, a batch rectifier is used to concentrate the waste in order to obtain a distillate with a higher calorific value, which is then sent to off-site incineration either in a cement kiln or in a conventional waste solvent incinerator. The second alternative is a hybrid process composed by a batch rectifier and a pervaporation unit that processes in batchwise mode the first cut from the distillation task to obtain a dehydrated solvent. Here, four scenarios are considered, comprising two kinds of membrane materials and two different vacuum systems.

For each alternative, the conceptual design was carried out with the aid of conceptual models of the unit operations involved. Quasi-optimal values for design and operation variables were used as input data to perform an economical and an environmental assessment of each alternative. The economic analysis suggests that the hybrid process is the best alternative given that the replacement cost of fresh solvent (about 850 U$S/ton) is considered as a credit value.

From the environmental analysis with life cycle assessment, two main conclusions can be drawn: i) the use of the distillate as an alternative fuel in a cement kiln leads to a reduction in emissions that is relevant for the categories related to human health and ecosystem quality; and ii) in terms of resource depletion, the hybrid process distillation/pervaporation with the ceramic membrane HybSi (Pervatech) shows the lowest impact due to the solvent recovery.  相似文献   


19.
In recent years, biobased polymers have gained attention from industries, consumers and governments as a way to reduce municipal solid waste. Much attention has been given to their production and implementation. However, these materials only reach their potential environmental benefits when they are recovered through recycling or composting and/or their energy is recovered by incineration. These end‐of‐life scenarios allow closing the carbon cycle loop. A lot of confusion and misunderstanding about these new materials and their end‐of‐life scenarios, particularly composting, have been generated. This paper addresses definitions and environmental performance of these materials and their compostability. Current methods for measuring biobased content and biodegradability of polymers and factors affecting it, such as exposure conditions and polymer characteristics, are discussed, and the use of life cycle assessment as a tool to evaluate the environmental performance of biopolymers is presented. Although there are some obstacles for the growth and implementation of biobased polymers, such as consumer adoption and available composting facilities accepting these materials, new opportunities are growing due to government regulation and business initiatives in the past five years. However, consumers' understanding of when the use of these materials provides environmental benefits and when not is still missing. Therefore, to adopt and to implement these new biopolymers cooperative work among industry, consumers and government is needed. Copyright © 2008 Society of Chemical Industry  相似文献   

20.
Decomposition of nitrocellulose‐based propellant is a well‐known problem that results in insufficient shelf‐life of the ammunition if the propellant is not stabilized with appropriate materials. To investigate the influence of storage conditions on the shelf life of old propellant powder HPLC analytics according to AOP‐48 were carried out to determine the stabilizer consumption at different temperatures. The ingredients of the propellant were also analyzed. The results show that the examined propellant samples from WW II production are still containing stabilizer. Humidity in combination with elevated temperature seems to be the most influencing parameter for decomposition of this type. The analyzed propellants seem to be stable even after about 70 years under bad storage conditions. You might draw conclusions from these results for modern time propellant powders, which are stored under controlled conditions.  相似文献   

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