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关键词： Shoe manufacturing waste   Ash   Heavy metals   PCDD and PCDF   Ash fusion temperature  

摘要： The ash formation behaviour and associated compositional characteristics of the combustion of shoe manufacturing waste (SMW) in a 2.5 MW(th)pilot-scale circulating fluidized bed combustor (CFBC) were investigated to better understand the combustion behaviour and to find effective management strategy for the disposal of the ash streams produced. The compositional characterisations for the ashes produced from the pilot demonstrations showed the presence of a variety of trace heavy metals both in the fly ash and bottom ash. A pronounced uneven partitioning behaviour was observed on the distribution of these heavy metals between the fly ash and bottom ash, and it was found that all the heavy metals except chromium were preferentially enriched in the fly ash, with the contents of lead and cadmium in the fly ash being over 11 and 6 times higher than in the bottom ash. Leaching tests demonstrated that the concentrations of most of the aforementioned metals present in the leachates from the fly ash and bottom ash could meet the permissible limits for landfill disposal but with lead as an exception with its concentration in the fly ash leachates being over 2 times higher than the limit. The total PCDD and PCDF contents both in the fly ash and bottom ash were also much below the legal limit. To further understand the ash behaviour, the slagging and fouling tendency during SMW combustion in the CFBC was examined by use of the characterisation of the ash mineralogy and the results indicated that the SMW ash likely had low tendencies for slagging and fouling. The best two valorization routes for the SMW bottom ash and fly ash were recommended, one being to use them to produce colloidal silica medium to obtain safe inert filler and the other being to use them as the raw materials in the cement industry. [GRAPHICS] .

关键词： Drying  

摘要： This study reveals the low temperature high velocity (LTHV) assisted fluidized bed drying can preserve to the bioactive components of bee pollen. LTHV assisted fluidized bed drying characteristics of bee pollen. For this purpose, 100 g of the raw bee pollen samples are used to the investigation of drying characteristics at 4, 10, 24, and 40 degrees C, 40-50 humidity (%) and 6 m/s air velocity. In this regard, moisture loss, dimensionless mass loss, equilibrium moisture content, drying rate, drying time, mass shrinkage, some product characteristics, and sensory quality characteristic were investigated. Finally, the best drying air temperature was selected as 10 degrees C because the bee pollen samples had the best drying performance and sensory quality scores. LTHV assisted fluidized bed drying can be used for bioactive bee pollen drying. Practical applications The LTHV assisted fluidized bed drying is a new drying application that preserve to the sensitive food and bioactive food component. This method is usable for sensitive drying applications as medical and bioactive product production applications for the highest quality and safety production.

摘要： This thesis consists of two parts. In the first part, we consider various techniques for analyzing a finite volume method. The techniques discussed are the modified equation approach, numerical experiments, Fourier-mode analysis and the energy method. In the second part, we construct a finite volume discretization for the advection term of the shallow- water equations on a 2D triangular grid. For the control volumes of the momentum equation, we chose the quadrilaterals that arise by connecting the vertices of a triangular grid cell with its cen- troid. This choice of control volume makes it possible to define velocity reconstructions, based on the normal-directed velocities alone, that are very suitable for approximating the advection term. The constructed discretizations are tested for their accuracy and their sensitivity for grid-perturbations.

关键词： Circulating fluidized bed   cluster   image processing   high-speed video camera   gas-solid flow  

摘要： The paper presents an analysis of measurement results on cluster and cluster core properties in a rectangular circulating fluidized bed riser. Experiments were carried out under different superficial gas velocities in the range of 4.5 m/s to 5.5 m/s along with solids circulation rate up to 272 kg/m(2)center dot s. High-speed images of the bed were taken in a controlled lighting environment. Analysis of the experimental images was conducted to demonstrate the microscopic structure of particle clusters. A cluster always consists of a dense core with highest solids holdup and the relatively dilute cluster cloud. Additionally, the horizontal length scale distribution as well as the solids concentration inside the clusters were evaluated, respectively. The effects of superficial gas velocity, solid circulation rate and the elevation on the measured cluster properties were determined. Results indicate that both a higher solid circulation rate and a lower gas velocity are benefited for cluster formation. Besides, at the top of the riser, the impact of the riser outlet structure becomes serious under high gas velocities, giving rise to wider clusters. Furthermore, narrow clusters with widths below several millimeters, which insensitive to the variation of operating conditions, are common in all position of the CFB riser.

关键词： 平滩白钨矿床   加里东期成矿   流体包裹体   S同位素   沸腾作用   成矿机制  

摘要： 平滩白钨矿床位于南岭西段的苗儿山-越城岭岩体西部,为一新发现的形成于加里东期的矿床。对平滩钨矿床中的含钨石英脉进行了流体包裹体的研究,依据矿物共生组合以及石英脉的穿插关系将其成矿过程划分为两个阶段:石英−白钨矿阶段(Ⅰ)和石英−硫化物阶段(Ⅱ)。从第Ⅰ阶段到第Ⅱ阶段,均一温度从260~380℃明显降低到240~300℃,其盐度也呈明显下降趋势(平均盐度分别为11.26%NaCleqv和8.61%NaCleqv)。激光拉曼成分分析结果显示,第Ⅰ阶段的流体包裹体中含有CO2、CH4和N2等气相成分,明显区别于第Ⅱ阶段。第Ⅰ阶段中一定比例的含子晶流体包裹体以及各阶段石英脉中金属硫化物的δ34S组成为(−0.491×10^−3^+2.065×10^−3),平均为+0.496×10^−3,表明其成矿流体来自于岩浆水。引起钨矿质沉淀的主要原因为成矿流体的沸腾作用;平滩钨矿主要为源自于地壳重熔的岩浆经高度的分异演化后,富含钨矿质的岩浆热液经历了沸腾作用所形成。

关键词： 风速   不确定度   皮托管   微压计  

摘要： 常见的风速计检定装置由风洞和皮托管-微压计风速标准器两部分组成,前者受工作段气流均匀性、稳定性影响,后者受温度、湿度、大气压和皮托管系数、微压计不确定度的影响,其中由于温度、湿度、大气压引入的不确定度数值小,可忽略不计。随着风速的增大,风速计检定装置不确定度呈现先减小后增大的规律,在9.1m/s时达到最小;而检定装置的相对不确定度在快速下降后,逐渐减小,逐渐趋近于常数。在低风速段(<10m/s),微压计引入的不确定度较显著;在高风速段,风洞工作段的不稳定性和不均匀性引入的不确定度较显著。

关键词： 离心泵   冲击损失   摩阻损失   解决措施  

摘要： 主要探讨离心泵流动损失的形成因素,并结合工作经验,提出了一些减小流动损失的措施,对离心泵的设计有一定的参考意义。

关键词： 液体表面张力系数   光纤   拉力传感器   拉脱法  

摘要： 基于法布里-珀罗干涉型拉力传感器,利用拉脱法测量了液体表面张力系数.设计制备出的光纤拉力传感器结合单频激光器、光纤环形器、光电探测器可使输出电压和拉力成正比,其灵敏度约为64.5 mV/N.利用其测量室温下水的液体表面张力系数(0.076±0.001)N/m,相对偏差为4.1%.

关键词： 水化学类型   同位素   热储温度   水文地球化学  

摘要： 地热流体的水文地球化学特征及演化可以揭示地热水的深部循环机理,对地热资源的开发利用有着重要意义。基于容城地热田的地热地质条件,本文选取了容城地热田16个深部地热井水和2个保定山区浅层冷水井进行了水化学特征及同位素分析,计算了热储温度和热循环深度,最后进行了反向水文地球化学路径模拟分析地热流体在深部的水岩反应运移过程。结果表明研究区深部地热井水化学类型为HCO3·Cl-Na型,保定山区水化学类型为HCO3-Ca·Mg型,在容城地热田中几乎所有离子与Cl都不存在显著正相关关系,微量元素主要来源于相关矿物的溶解。容城地热田Na+浓度很高,说明容城地热田的地下水径流较长,热循环深度大,HBO2的含量较多,说明其地下热水径流较小,流速比较弱。D、18O同位素基本在大气降水线附近,计算地热井的补给高程为665.17~165.17m,与保定山区海拔相近,表明了研究区地热水来源为山前补给和大气降水。研究区深部热储温度为57~98℃,热循环深度在1331~2483m之间。