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排序方式: 共有341条查询结果,搜索用时 31 毫秒
91.
为研究废弃印刷电路板(PCB)在回收加热拆解电子元件过程中所产生的气体排放物的主要成分,使用自行设计的废弃PCB拆解装置进行拆解实验,采用傅里叶红外光谱(FTIRS)、气相色谱-质谱(GC/MS)、离子色谱(IC)和电感耦合等离子体质谱(ICP-MS)等分析方法,对实验过程所收集到的气体产物进行成分分析.结果表明,废弃PCB的基板在加热过程中发生了初步分解,基板上的溴化环氧树脂发生了O—C、C—C、C—Br键的断裂,产生了苯酚、2,6-二溴苯酚等有机物;伴随有机气体逸出的还有废弃PCB在加热过程所释放的含有大量S、N、Cl、Br等元素的无机酸性气体;而连续的熔锡过程还使得PCB与焊料中的Sn、Pb、Sb、Hg、Cd、Cr等重金属产生烟尘逸出. 相似文献
92.
对于盐分的研究是以通过湿热法餐厨垃圾制作适宜益生菌生长基质为目标.研究选取益生菌生长的主要限制因素-盐分进行研究,确定降低盐分浓度的工艺条件.实验通过选取一定温度、加水量和反应时间条件,在高温高压反应釜中反应.研究发现,全盐适宜温度为100℃或140℃,水溶性氯离子和水溶性钠离子适宜温度为50℃;三种离子适宜加水量均为80%;三种离子适宜的反应时间为15 min.研究为餐厨垃圾制作成适宜益生菌生长的工艺奠定了基础,较深入地研究了盐分在预处理过程中的变化情况和趋势. 相似文献
93.
《Journal of Manufacturing Processes》2014,16(2):176-182
Cladding is generally characterized by partial dilution of the substrate and hence formation of metallurgical bonding between the substrate and the deposits. Laser cladding is one of the most widely practiced surface engineering techniques. The present work mainly focuses on a novel development in surface engineering techniques in the form of microwave cladding. Clads of tungsten carbide (WC) based WC10Co2Ni powder on austenitic stainless steel were produced using microwave hybrid heating. Microwave clads were developed by exposing the preplaced, preheated powder for a duration of 120 s to microwave radiation at 2.45 GHz frequency and 900 W power in a home microwave system. Characterization of the clads was carried out in the form of microstructural and elemental composition studies. Investigations show crack-free interface revealing good metallurgical bond associated with partial dilution of the stainless steel substrate and full melting of WC particles. Typical X-ray diffraction results confirm presence of metallic carbides in the clad which is primarily responsible for significantly higher microhardness of the clad. Process mechanism has been discussed. 相似文献
94.
分析了稠油开采过程中螺杆泵传统电缆加热方式的不足,提出新型电磁水循环加热方式,实现了现场安全、节能和环保的提升,且能提高原油日产量。 相似文献
95.
Multiple regression models for the lower heating value of municipal solid waste in Taiwan 总被引:1,自引:0,他引:1
A multiple regression analysis was used to develop two predictive models of lower heating value (LHV) for municipal solid waste (MSW), using 180 samples gathered from cities and counties in Taiwan during 2001-2002. These models are referred to as the original proposed model (OPM) and the simplified model (SM). The coefficients of multiple determinations for the OPM and SM were 0.983 and 0.975, respectively. To verify the feasibility of the models, a demonstration program based on sampling of MSW in Kaohsiung City was conducted. As a result, the OPM showed superior precision in terms of relative percentage deviation (RPD) and mean absolute percentage error (MAPE), when compared to the conventional models based on the proximate analysis, physical composition and ultimate analysis. The SM was derived by neglecting the three minor physical components used in the OPM. The resulting SM was less precise when compared to the OPM, but it was still acceptable, with a precision level better than the conventional models. It was concluded that the predictability of empirical models could be improved significantly through selection of the appropriate physical components and multiple regression analysis. 相似文献
96.
Petersdorff C Boermans T Harnisch J 《Environmental science and pollution research international》2006,13(5):350-358
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Goal Scope and Background. The European Directive on Energy Performance of Buildings which came into force 16 December 2002 will be implemented in the legislation of Member States by 4 January 2006. In addition to the aim of improving the overall energy efficiency of new buildings, large existing buildings will become a target for improvement, as soon as they undergo significant renovation. The building sector is responsible for about 40% of Europe's total end energy consumption and hence this Directive is an important step for the European Union in order that it should reach the level of saving required by the Kyoto Agreement. In this the EU is committed to reduce CO2 emissions relative to the base year of 1990 by 8 per cent, by 2010. But what will be the impact of the new Directive, how large could be the impacts of extending the obligation for energy efficiency retrofitting towards smaller buildings? Can improvement of the insulation offset or reduce the growing energy consumption from the increasing installation of cooling installations? EURIMA, the European Insulation Manufacturers Association and EuroACE, the European Alliance of Companies for Energy Efficiency in Buildings, asked Ecofys to address these questions.Methods
The effect of the EPB Directive on the emissions associated with the heating energy consumption of the total EU 15 building stock has been examined in a model calculation, using the Built Environment Analysis Model (BEAM), which was developed by Ecofys to investigate energy saving measures in the building stock. The great complexity of the EU-15 building stock had to be simplified by examining five standard buildings with eight insulation standards, which are assigned to building age and renovation status. Furthermore, three climatic regions (cold, moderate, warm) were distinguished for the calculation of the heating energy demand. This gave a basic 210 building types for which the heating energy demand and CO2 emissions from heating were calculated according to the principles of the European Norm EN 832.Results and Discussion
The model calculations demonstrates that the main contributor to the total heating related CO2 emissions of 725 Mt/a from the EU building stock in 2002 is the residential sector (77%) while the remaining 23% originates from non-residential buildings. In the residential sector, single-family houses represent the largest group responsible for 60% of the total CO2 emissions equivalent to 435 Mt/a.-
- The technical potential: If all retrofit measures in the scope of the Directive were realised immediately for the complete residential and non-residential building stock the overall CO2 emission savings would add up to 82 Mt/a. An additional saving potential compared to the Directive of 69 Mt/a would be created if the scope of the Directive was extended to cover retrofit measures in multi-family dwellings (200-1000m2) and non-residential buildings smaller than 1000m2 used floor space. In addition including the large group of single-family dwellings would lead to a potential for additional CO2 emission reductions compared to the Directive of 316 Mt/a.-
- Temporal mobilization of the potential: Calculations based on the building stock as it develops over time with average retrofit rates demonstrated that regulations introduced following the EPB Directive result in a CO2 emissions decrease of 34 Mt/a by the year 2010 compared to the business as usual scenario. Extending the scope of the EPB Directive to all residential buildings (including single and multi-family dwellings), the CO2 emission savings potential over the 'business as usual' scenario could be doubled to 69 Mt/a in the year 2010. This creates an additional saving potential compared to the Directive of 36 Mt/a.-
- Cooling demand: The analysis demonstrated that in warm climatic zones the cooling demand can be reduced drastically by a combination of lowering the internal heat loads and by improved insulation. With the reduction of the heat loads to a moderate level the cooling demand, e.g. of a terraced house located in Madrid, can be reduced by an additional 85% if the insulation level is improved appropriately.Conclusions
This study demonstrates that the European Directive on Energy Performance of Buildings will have a significant impact on the CO2 emissions of the European building stock. The main saving potential lies in insulation of the existing building stock. Beyond this, CO2 emissions could, however, be greatly reduced if the scope of the Directive were to be extended to include retrofit of smaller buildings.Recommendation and Perspective
The reductions should be seen in relation to the remaining gap of 190 Mt CO2 eq. per annum between the current emission levels of EU-15 and the target under the Kyoto-Protocol for the year 2010. The energy and industrial sector will probably contribute only a fraction of this reduction via the newly established EU emissions trading scheme and connected projects under the flexible mechanism. In addition, the traffic sector is likely to continue its growth path leading to a widening of the gap. Thus, there is likely to be considerable pressure on the EU building sector to contribute to the EU climate targets beyond what will be achieved by means of the current EPB Directive. Legislators on the EU and national level are therefore advised to take accelerated actions to tap the very significant emission reduction potentials available in the EU building stock. 相似文献97.
DDS系列煤炭自燃阻化剂实验研究 总被引:11,自引:0,他引:11
为寻找高效阻化剂以防止煤炭自热引燃,在控温炉中对DDS系列煤自燃阻化剂的阻化效果进行了实验研究,并与经前的阻化剂做了比较。实验采用烟煤作为试样,借助于著名的Frank-Kamenetskii模型,利用4,6,8和10厘米立方体阻化煤磁地60-220℃温度范围估测其氧化反应的活化能。 相似文献
98.
通过调查,分析了供热方式与环境质量的关系,比对了集中供热与分散供热环境效益和经济效益。到本世纪末可实现供热规化后,使城市热化率达到20%。市内大气环境质量将有较大改善。 相似文献
99.
集中供热-缓解乌鲁木齐大气污染的有效途径 总被引:8,自引:1,他引:8
针对乌鲁木齐大气污染的现状,重点介绍了集中供热在治理城市大气污染中发挥的重要作用,阐明了推广热电联产、集中供热以及清洁能源对改善乌鲁木齐市空气环境质量的重要意义.指出在现阶段发展集中供热工程,仍将是缓解和改善乌鲁木齐大气污染的有效途径之一. 相似文献
100.