Colonial Settlers and the Metropole: Racial discourse in the early 19th-century Cape Colony,Australia and New Zealand

The ways that British settlers in South Africa, Australia and New Zealand, particularly those engaged in the extension of commercial sheep farming, constructed a certain discourse of colonialism during the first half of the 19th century are discussed. It is argued that this discourse was formulated, at least in part, in opposition to that of humanitarians within each colony and in Britain, who challenged settler capitalist practices on the fringes of Britain's expanding empire. Representations of a civilizing impact on the landscape were one component of the new racialized understandings and identities that settlers at each site constructed in their defence. Through attention to three colonial sites and their relations with each other and with the metropole, it is aimed to highlight the ways in which discourses of colonial landscapes and their inhabitants travelled across an imperial terrain.     

Structural optimization of a settler via CFD simulation in a mixer-settler

This work is aimed at optimizing a settler structure in a mixer-settler.Two different aspects have been considered.Firstly,the flowcharacteristics of a settler have been examined by computational fluid dynamics(CFD)simulation with various agitation speeds of the mixer,as well as organic phase volume fractions ranging from 0.075 to 0.6.The aqueous and organic phase turbulent flow fields were measured by particle image velocimetry(PIV) technique to verify the CFD simulation.Two organic phases with different physical properties were assessed in the CFD simulation to simulate the liquid-liquid systems related to rare earth element extraction,i.e.,0.072 mol·L~(-1) P507/kerosene and 1.8 mol·L~(-1) P507/kerosene.Secondly,the CFD simulation was carried out in a settler equipped with baffles.The effects of number and location of the baffle in the settler on flow features and entrainments of the aqueous and organic outlet were analyzed.Meanwhile,different settler/mixer volume ratios were also examined.By analyses and comparisons,an optimal design for settler was proposed.CFD can provide a significant guidance to better mixer-settler design.     

斜板沉降器内油粒运动规律分析

在对斜板间连续流场的研究基础上,采用离散相模型结合自编程对在错流、并流和逆流的3种流动形式中Stokes油滴运动规律进行模拟计算:该油滴在垂直于板方向上浮速度相同,与流动形式无关,其上浮时间正比于分离场的高度,在板间距相同条件下,上浮到上板所需时间相同,但逆流时油滴迁移距离最短,与流动形式有关;油滴运动位移和浮升时间随斜板倾角α增大而增长。     

Fermentation and elutriation of primary sludge: effect of SRT on process performance

A primary sludge fermentation-elutriation pilot plant was operated using in-line and side-stream schemes. The influence of solids retention time, recirculation sludge flow-rate and solids concentration on the fermentation-elutriation process performance has been assessed in this paper. The use of high elutriation flows (12% of influent flow) improved the volatile fatty acids (VFA) concentration in the effluent stream. Suspended solids removal efficiency decreased in the primary settler when the solids retention time (SRT) was increased from 4 to 8 days. Disintegration step during hydrolysis process was pointed out as the main reason for that decrease. Maximum VFA productions were achieved at SRT between 6 and 8 days at the highest elutriation flow tested for both configurations. Propionic, butyric and valeric volatile fatty acids percentage increased when total solids sludge concentrations above 23,000mgl(-1) were used. Hydrogen accumulation, causing acetogenic bacteria inhibition, was indicated as the reason for C(3)-C(5) fatty acids accumulation.     

铜合成熔炼炉结构设计特点

结合设计实践,详细论述了金川铜合成熔炼炉的结构设计特点。     

斜板沉降器处理负荷的计算

依据双膜模型和液滴在斜板层膜上的有效聚结 ,对层膜层流的临界雷诺数进行了关联 ,得出了斜板沉降器处理负荷的计算式。经实验数据验证 ,处理负荷的计算误差在 8%以内。     

金隆闪速炉本体改造

根据金隆的发展要求,并结合金隆的生产实践,阐述了金隆闪速炉本体的改造措施。     

催化裂化装置沉降器内顶旋升气管外壁结焦的特性分析

对炼油厂催化裂化装置沉降器内顶旋升气管外壁结焦的微观结构和外观特点所作的分析表明,升气管外壁的结焦主要是由液滴状结焦和细催化剂颗粒组成,结焦组织致密,焦块硬脆；结焦厚度沿圆周分布不均,以入口为0°,结焦厚度从0°约2cm向后逐渐增厚,表面有明显的冲刷沟槽,180°向后表面形成尖牙状结焦,厚度达10cm。升气管表面结焦是重组分油气冷凝形成的液滴和细催化剂颗粒沉积粘附在升气管表面发生结焦反应,并不断长大形成的。升气管表面结焦过程属于沉积型结焦,与升气管附近的流场密切相关。     

结构参数对旋流沉降组合油水分离器性能的影响

对影响旋流沉降组合式油水分离装置分离性能的不同操作参数进行了试验研究。在大量试验数据的基础上,分析了旋流器不同叶片数、出口角,沉降器板长、倾角、板间距及聚结材料对分离性能的影响,试验确定了各个结构参数的适宜值。     

新型液-液分离设备——斜板沉降器

介绍了斜板沉降器的结构和操作特性，并对液滴在斜板层膜上的聚结过程以及影响液滴聚结的因素进行了分析；提出了液滴在斜板上有效聚结作为斜板沉降器的设计依据，最后对斜板沉降器的进一步研究重点提出了建议。