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51.
主要论述了一种钢线拉丝及表面处理生产线成套装备的设计。该生产线的生产方式是多根钢线在牵引动力系统的作用下依次穿过各种处理设备,完成各道工序,实现钢线完成表面处理的目的。这个生产过程中,钢线可以完成放线、脱脂、退火、镀镍、造膜、烘干及收线一体化的工序。采用立体式布置,空间利用更为合理。 相似文献
52.
Agata Witczak Agnieszka Patrzykąt 《Journal of environmental science and health. Part. B》2013,48(2):191-197
The aim of this study was to compare recoveries of organochlorine pesticides (heptachlor, α-HCH, β-HCH, γ-HCH, op′-DDD, pp′-DDD, pp′-DDE, op′-DDT, pp′-DDT) from fish muscle dried by two alternative methods: (i) grinding with anhydrous sodium sulphate and (ii) freeze drying. Pesticide residues content was determined by gas chromatography-mass spectrometry (GS-MS) method. For four pesticides (γ-HCH, α-HCH, heptachlor and pp;-DDD) in four of five fish species, higher recoveries were obtained from the freeze-dried samples. For five remaining pesticides, correlations between fish species and drying method were not found. The results of this study do not clearly indicate which drying method caused lower losses of analytes. Recoveries from the freeze-dried samples ranged from 69.9 to 117.6 %, while recoveries from the samples ground with sodium sulphate varied from 64.4 to 126.7 %. Either of the methods gave satisfactory recoveries and they both can be used interchangeably. 相似文献
53.
高温生物滤塔处理污泥干化尾气的研究 总被引:1,自引:1,他引:0
利用高温生物滤塔处理污泥干化产生的尾气,气体处理量为2 700~3 100 m~3·h~(-1),停留时间为21.88~25.10 s,研究启动期和稳定运行的运行效果.生物滤塔能有效去除干化尾气中的SO_2、氨以及挥发性有机物,去除率分别达到100%、93.61%以及87.01%.微生物分析结果显示,生物滤塔内形成稳定的生物系统,填料和溶液中生长一定量的细菌和硫细菌.主要功能种群包括类芽孢杆菌Paenibacillus sp.,螯台球菌Chelatococcus sp.,芽孢杆菌Bacillus sp.,梭菌Clostridium thermosuccinogerws,假黄单胞菌Pseudoxanthomonas sp.,地芽孢杆菌Geobacillus debilis.大部分为脱氮、脱硫或者降解挥发性有机物的嗜热菌. 相似文献
54.
在测定市政污泥、印染污泥和造纸污泥中汞含量及其存在形态分布特征的基础上,通过模拟实验,系统研究了不同类型污泥中汞存在形态在干化过程中的动态变化,同时分析了污泥中汞含量和各存在形态发生变化的原因.结果表明,市政污泥的汞含量依次大于印染污泥和造纸污泥;污泥中无酸溶态汞和可还原态汞,只存在可氧化态汞和残渣态汞;被试污泥在25~100℃干化时,含水率降低不会导致汞的析出;在100~200℃干化时,污泥中汞含量随温度的升高呈现出缓慢降低的趋势;当干化温度200~300℃时,随污泥中有机质和硫化物的分解,可氧化态汞消失;当干化温度达到400℃时,污泥中汞不复存在. 相似文献
55.
对RHONE-POULENC白炭黑公司的干燥系统进行了噪声综合治理。主要措施有:大型引风机隔声罩、引风机排气筒消声塔,加热炉和鼓风机隔声机房,雾化加速器活动隔声罩,管道隔声包扎等。治理后厂界噪声由74dB(A)降至45dB(A)。 相似文献
56.
57.
In the present work, the thin layer drying kinetics of potato during natural convection solar drying was investigated experimentally. Cylindrical potato samples with length 50 mm and varying diameter of 8, 10 and 13 mm were dried in an in-house designed and fabricated laboratory scale mixed-mode solar dryer. Thirteen different thin-layer mathematical models were fitted to the experimental moisture ratio (MR) data. The obtained results indicated that the Modified Page model could satisfactorily describe the drying curve of potato cylinders with higher value of R2 and lower values of RMSE and χ2. The shrinkage parameter is incorporated in the analytical diffusion model to study the moisture transfer mechanism of potato cylinders. It was observed that the values of effective diffusion coefficient (Deff) and convective mass transfer coefficient (hm) are overestimated in the range of 85.02–90.27% and 39.11–45.11% for the range of sample diameter examined, without considering the shrinkage effect in the mass transfer analysis. A Multiphysics approach was adopted in this study to get insight into the drying behavior of potato cylinders in terms of food-moisture interactions during the solar drying process. The predicted results of MR are in close agreement with the experimental data. Moreover, the anisotropic behavior of shrinkage as well as the moisture distribution inside the potato cylinder was very well described by Multiphysics model. 相似文献
58.
59.
在木制品生产行业中,木材干燥是木制品加工生产工序中的一个重要环节,而在木材干燥生产中突出的问题是木材变形、开裂、木材含水率不均匀和霉变、虫蛀等。针对上述问题,设计出以高性能AVR微控制器为核心,应用恒流源、高分子湿敏电容和动态补偿等技术的全自动木材干燥测控系统。实验结果表明,木材干燥测控系统能保证产品质量,提高生产效率,硬件可靠性高,有工程实用价值。 相似文献
60.
Anionic surfactant (AS) concentrations in wet up-flow anaerobic sludge blanket reactor (UASBR) sludges from five sewage treatment plants (STPs) were found to range from 4480 to 9233mgkg(-1)drywt. (average 7347mgkg(-1)drywt.) over a period of 18 months. After drying on sand drying beds (SDBs), AS in dried-stabilized sludges averaged 1452mgkg(-1)drywt., a reduction of around 80%. The kinetics of drying followed simple first-order reduction of moisture with value of drying constant (k(d))=0.051d(-1). Reduction of AS also followed first-order kinetics. AS degradation rate constant (k(AS)) was found to be 0.034d(-1) and half-life of AS as 20 days. The order of rates of removal observed was k(d)>k(AS)>k(COD)>k(OM) (drying >AS degradation>COD reduction>organic matter reduction). For the three applications of dried-stabilized sludges (soil, agricultural soil, grassland), values of risk quotient (RQ) were found to be <1, indicating no risk. 相似文献