烟气输运和水喷淋相互作用的大涡模拟研究

本文应用大涡模拟方法，并结合Smagorinsky亚格子尺度模型，数值研究了烟气输运和水喷淋的相互作用问题。为了有效地模拟烟气输运过程，文中采用低马赫数近似下的三维可压缩Navier-Stokes方程和组分方程进行求解，并采用有限差分法数值计算了滤波后的控制方程。对于燃烧过程扣所产生的热释放，采用Lagrangian粒子携带热量的近似方法来模拟，这些运动粒子进一步用来标识烟气的输运过程，同时还近似模拟了水喷淋和热气流的相互作用过程。文中数值计算了燃烧火源所形成的热气流和烟气输运过程，以及与水喷淋的相互作用，并探讨了喷水装置的喷水量、喷射角和水颗粒直径对流动特性的影响。     

速生杨木粉尘最小点火能的实验研究

为防止木材加工中木质粉尘燃爆事故的发生,以纤维板生产中常见的原材料速生杨木粉尘作为研究对象,在分析粉尘粒径分布、元素分析、工业分析及形貌特征的基础上,采用1.2 L哈特曼管对3种不同粒径（0~50,＞50~96,＞96~180 μm）速生杨木粉尘进行最小点火能实验,探究点火延迟时间、喷粉压力、质量浓度和粒径分布对速生杨木粉尘最小点火能的影响及变化规律。研究结果表明:在质量浓度为500 g/m3时,分别增加点火延迟时间和喷粉压力,最小点火能都先减小后增大;最佳点火延迟时间和最佳喷粉压力分别为120 ms和120 kPa;粒径对最佳点火延迟时间和最佳喷粉压力无显著影响。在点火延迟和喷粉压力分别为120 ms和120 kPa条件下,最小点火能随质量浓度的增加先减小后增大。粉尘粒径与最小点火能呈正相关性,3种样品的最小点火能分别为1~3,1~3和7~13 mJ,对应的敏感质量浓度分别为500 ,750和1 250 g/m3,属于特别着火敏感性粉尘。     

Wind energy and natural ventilation potential of a wind catcher in Yazd – Iran (a long-term measurement)

When designing energy efficient buildings it is useful to study existing climate—responsive building typologies. The wind towers or wind-catchers of Yazd city in Iran are typical examples of such a typology. Although many previous studies have investigated the performance of various types of wind catcher systems, studies based on a long-term real-life measurement can be rarely found. In this study a long-term whole year monitoring campaign on an existing full scale four sided wind catcher in Yazd was carried out in 2014–2015. Three prevailing wind directions were identified and the measured on-site wind speeds were used to estimate the wind induced natural ventilation potential of the tower. A shaft/tower airflow performance index was developed. The monitoring results were compared to the ASHRAE Standard 62:2001 ventilation rate requirement. Results show that the total ventilation rate of the wind tower surpasses the ASHRAE Standard requirements. Furthermore it shows that the shafts are exposed to the prevailing wind directions perform better. For more effective natural ventilation a wind tower with adaptable openings/shafts are proposed.     

多棱插接式钢管塔风振阻尼技术研究

多棱插接式钢管塔具有制作安装方便、占地面积小等独特优势,正在得到越来越多的应用。但这种结构属于风敏感结构,风振特性是设计必须考虑的关键因素。钢管塔结构为空间薄壁壳体结构,其结构分析设计尤其是风振反应分析和风振控制与传统的杆系塔架结构有很大的不同。在静动力分析的基础上,提出利用钢球减振器对钢管塔进行风振控制,基于状态空间描述法模拟了钢管塔受控前后的位移时程反应,时域与频域分析结果表明该减振装置可以使结构的阻尼增加3~5倍,结构的风振反应可减小30%。本文的研究为钢管塔结构的合理设计提供了基础,有助于其在我国的推广应用,同时为行业规范和高耸结构设计规范的修订提供必要的理论基础。     

处理高浓度粉尘的除尘器的选择

密相干塔烟气脱硫工艺是一种半于法烟气脱硫工艺,布袋除尘器用来处理该系统中的高浓度粉尘,在国内还没有广泛地应用.通过对布袋除尘器和静电除尘器的技术经济比较,说明布袋除尘器优于静电除尘器,并通过中试验证布袋除尘器在此工艺中的适用性.     

OI~2-WFGD-Ⅱ烟气脱硫技术介绍

简要介绍了江苏苏源环保工程有限公司开发的OI^2-WFGD-Ⅱ湿法烟气脱硫技术的工艺特点、设备布置、技术参数、设备国产化以及技术应用。     

双循环多级水幕吸收塔烟气除尘脱硫性能研究

以改进后的双循环多级水幕塔对烟气进行除尘脱硫性能的研究,利用双循环不同pH值控制的优点和多级水幕的效果,增加气液接触面积和传质动力,提高SO₂吸收效果。在正交实验的最佳运行工况基础上,实验从烟气流量、上下两段pH、L/G和SO₂进气浓度等方面进行单因素研究。结果表明,除尘效率维持在98%以上,进气SO₂浓度在5 000 mg/m³以下时,脱硫率在93%以上。上段pH值为6、下段pH值为5、L/G在15左右的脱硫效率和运行工况最佳,无结垢现象发生。改进后的吸收塔具有良好的应用前景,实验结果对于现场脱硫设备的调试和运行有很好的参考价值。     

锅炉尾部烟道直接喷水调质技术的研究

对排烟温度低于160 ℃的锅炉尾部烟道内直接喷水调质技术进行了探讨,从实际应用情况来看,此项技术改造规模小,不影响除灰系统正常运行,并且能提高1%～2.5%的除尘效率.     

An Automated Wet Deposition System to Compare the Effects of Reduced and Oxidised N on Ombrotrophic Bog Species: Practical Considerations

Critical N loads for ombrotrophic bogs, which often contain rare and N-sensitive plants (especially those in lower plant groups: lichens, mosses and liverworts), are based on very few experimental data from measured, low background N deposition areas. Additionally the relative effects of reduced versus oxidised N are largely unknown. This paper describes an automated field exposure system (30 km S. of Edinburgh, Scotland) for treating ombrotrophic bog vegetation with fine droplets of oxidised N (NaNO₃) and reduced N (NH₄Cl). Whim Moss exists in an area of low ambient N deposition (ca. 8 kg N ha^–1 y^–1), the sources and quantification of which are described. The wet N treatment system is run continuously, and is controlled/activated by wind speed and rainfall to provide a unique simulation of real world treatment patterns (no rain=no treatment). Simulated precipitation is supplied at ionic concentrations below4mMin rainwater collected on site. Treatments provide a replicated dose response to 16, 32 and 64 kg N ha^–1 y^–1 adjusted for ambient deposition (8 kg N ha^–1 y^–1). The 16 and 64 kg N ha^–1 y^–1 are duplicated with a P+K supplement. Baseline soil chemistry and foliar nutrient status was established for all 44 plots for Calluna vulgaris, Sphagnum capillifolium, Hypnum jutlandicum and Cladonia portentosa.     

湘西金矿溜矿井卸矿点尘源控制试验研究

通过对溜矿井卸矿点产尘及其特点的研究 ,提出了一种独特的防尘思维模式 ,并有针对地设计出一种自净式喷雾装置 ,适用效果良好。