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211.
212.
《Environmental engineering science》2011,28(11):775-779
Abstract An increasing demand for bio-based vehicle fuels and impending harsher regulations of CO2 emissions are driving the development of a second generation of ethanol fuel processes. These processes will increase yields and make new feedstocks available, as they are designed to handle lignocellulosic materials such as wood. In order to achieve a sound financial economy of such a process, as well as an acceptable degree of energy efficiency, it is of the utmost importance that the lignin produced has a high dry content. An experimental study was conducted on lignin slurry from a pilot plant in the north of Sweden, in which the lignin slurry was filtered, pressed, and characterized. The dewatering was evaluated with the classical filtration equation by determining the average specific filtration resistance of the filter cakes. Compared with previous work, relatively low values of the specific filtration resistance were obtained. It is probable that the low values were an effect of the high amount of cel... 相似文献
213.
Using a fire propagation model to assess the efficiency of prescribed burning in reducing the fire hazard 总被引:1,自引:0,他引:1
Nathalie Cassagne François PimontJean-Luc Dupuy Rodman R. LinnAnders Mårell Chloé OliveriEric Rigolot 《Ecological modelling》2011,222(8):1502-1514
We examined how fire hazard was affected by prescribed burning and fuel recovery over the first six years following treatment. Eight common Mediterranean fuel complexes managed by means of prescribed burning in limestone Provence (South-Eastern France) were studied, illustrating forest and woodland, garrigue and grassland situations. The coupled atmosphere-wildfire behaviour model FIRETEC was used to simulate fire behaviour (ROS, intensity) in these complex vegetations. The temporal threshold related to the effectiveness of prescribed burning in reducing the fire hazard was assessed from derivated fuel dynamics after treatment. The study showed that prescribed burning treatment was effective for the first two years in most of the Mediterranean plant communities analysed. Thereafter, all forests and shrublands were highly combustible with a fire line intensity of more than 5000 kW/m except for pine stands with or without oak (medium intensity of 2000 kW m−1 3 years after treatment). Low fire line intensity (900 kW m−1) was obtained for grassland which was entirely treatment-independent since the resprouter hemicryptophyte, Brachypodium retusum, is highly resilient to fire. Fire behaviour was greatly affected by fuel load accumulation of Quercus ilex in woodland, and by standing necromass of Rosmarinus officinalis in treated garrigue. Pure pine stands with shrub strata similar to garrigue showed a lower fire intensity due to wind speed decrease at ground level under tree canopy, underlining the advantage of maintaining a proportion of canopy cover in strategic fuel-break zones. 相似文献
214.
主要针对2011年冬季黑龙江省哈尔滨市地区降水过少而2012年春季极度干旱对森林可燃物含水率的影响进行研究。对在2011—2013年冬季反常气候影响下的黑龙江哈尔滨城市林业示范基地的樟子松、胡桃楸、白桦、蒙古栎林下可燃物含水率的动态变化进行了定点检测,并通过细致的分析发现随着气象条件的变化,不同森林可燃物含水率呈现出不同的变化趋势:樟子松林下可燃物含水率相比之下一直很高,胡桃楸林下可燃物含水率一直非常稳定,对环境条件的变化反映不太明显,而蒙古栎林下可燃物则处于中间,白桦林下可燃物对气象因子的变化最为敏感,上下波动很大。根据监测获得的数据对不同森林可燃物含水率和气象因子的关系进行了多元线性回归分析,并在符合一定条件的前提下建立了相对应的含水率预测模型,由于数据较少等原因,所得模型准确性有待验证,但是这也为哈尔滨城市林业示范基地森林含水率的预测奠定了基础。 相似文献
215.
王如君 《中国安全生产科学技术》2013,(12):73-77
为了进一步推广液化天然气(LNG)燃料动力船舶的应用,利用计算流体动力学(CFD)软件FLACS进行LNG燃料动力船进行三维建模,综合考虑环境方面的因素,对LNG的泄漏扩散进行模拟,在此基础上进行爆炸事故后果模拟。对爆炸事故进行分析,得到特定事故情景下的LNG扩散半径、燃烧区域半径、爆炸对人以及建筑物的危害半径,模拟结果对船舶上的管线以及消防设施的布局有一定的指导作用,并且为进一步研究LNG燃料动力船舶的安全性提供了基础数据。 相似文献
216.
Ralitsa Petrova Hiteva 《Local Environment》2013,18(4):487-505
The European Union (EU) and member states alike are following a tradition of addressing fuel poverty and vulnerability at the point of purchase by final consumers by seeking to influence the impact of income, energy price and the built environment on the ability of household consumers to access the energy that they need. By focusing on the conditions of energy transmission in the most rapidly growing renewable electricity sector in the UK – offshore wind – this paper aims to question whether the regulatory socio-technological framing of renewable electricity transmission is reproducing conditions for fuel poverty and vulnerability in the UK. By drawing a comparison with renewable electricity transmission in Bulgaria, this paper argues that the problem might be symptomatic of the EU as a whole. While not arguing against the proliferation of renewable electricity and its importance in meeting the 2020 targets, this paper calls for expanding the scope of fuel poverty alleviation policy throughout the whole renewable electricity supply chain, building on Helm's argument that energy companies at the middle of the supply chain are better suited to deliver fuel policy. 相似文献
217.
对压缩天然气加气子站的主要工艺技术特点、主要危险有害因素及安全设施设置情况进行了介绍与分析。 相似文献
218.
生物柴油制备工艺影响因素的探讨 总被引:1,自引:0,他引:1
介绍了生物柴油制备的基本工艺,着重阐述了催化剂、反应温度、反应时间、醇油比、水分以及游离脂肪酸含量对生物柴油制备的影响,并提出了生物柴油制备工艺今后的研究方向和开发前景。 相似文献
219.
构建了一种基于升流式厌氧污泥床反应器(UASB)的微生物燃料电池(MFCs),利用UASB高效去除COD能力及连续进样方式,获得稳定电能输出。考察了水力停留时间、进液方式、电极材料、离子交换膜种类、溶液离子强度等因素对于MFCs性能的影响。实验结果表明:在水力停留时间6h、连续进液、高纯石墨板电极以及均相阳离子交换膜条件下,连续运行3个月,放电功率稳定在145mW/m^2,开路电压0.78V,放电电流最高可达321mA/m^2。 相似文献
220.