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1.
以四川某地含钪、钛、稀土黏土矿为研究对象,进行钠盐焙烧-酸浸、直接酸浸、硫酸化焙烧-水浸、空白焙烧-酸浸探索试验。结果表明,直接酸浸、空白焙烧-酸浸对钪和钛的回收效果均不好。硫酸化焙烧-水浸对钛的回收效果很好,但钪的浸出率较低。钠盐焙烧-酸浸试验结果表明,适宜的焙烧条件为:碳酸钠用量80%,焙烧温度800℃,焙烧时间1h;适宜的浸出条件为:10v.%硫酸,液固比20:1,浸出温度60℃,搅拌浸出时间2h;钪的浸出率为89.98%,钛的浸出率为80.55%。液固比对钪和钛的浸出率有显著影响,增大液固比可以暂时解决硅酸造成的过滤困难的问题。   相似文献   
2.
丁华 《合成纤维》2015,44(4):44-47
介绍了半干法制酸工艺原理和工艺流程。在某黏胶生产线上运用半干法制酸装置处理来自酸浴的8 000 Nm3/h和来自纺丝的4 8000 Nm3/h湿性废气,通过补充硫磺3.3 t/h,可以生产硫酸300 t/d,吨酸回收1.65 t蒸汽。半干法制酸装置具有腐蚀性小、副产蒸汽多、电耗低、投资省、维护量少等优点。  相似文献   
3.
Thickening is one of the main attributes of high molecular weight poly(sodium acrylate) as a water-soluble polymer. The acrylate polymer was prepared through polymerization of NaOH-neutralized acrylic acid in aqueous solution. The reaction mixture was open to the atmosphere, providing unrestricted access to oxygen. The sodium metabisulfite/ammonium persulfate redox system was used as an initiator in the free-radical polymerization. After prevailing on a few synthetic practical problems, certain parameters affecting the reaction and product characteristics were studied. The parameters were the initiator and monomer concentration, reaction temperature, pH, and chain transfer agent (i.e., isopropanol). As-synthesizedpolymers were purified and evaluated viscometrically by a Brookfield viscometer (0.5 Wt% polymer solution in distilled water at 25°C). Intrinsic viscosity, [ m ], was also measured to calculate the viscosity average molecular weight (M v ) based on the corresponding Mark-Hawink-Sakurada equation. Changes of the isolated polymer yield, viscosity, M v , and a couple of indirect kinetic factors including gelation/reaction times and temperature were investigated according to the mechanism and known kinetic relationships of the free-radical addition polymerization. Finally, a useful Brookfield viscosity-M v curve was obtained and suggested to use for facile estimation of the average molecular weight of a typical poly(sodium acrylate) sample having medium to high molecular weight.  相似文献   
4.
以废旧毛涤黏混纺面料为研究对象,首先对面料进行清洁与消毒,然后对其组分进行定性、定量分析,最后通过单因素法优化,得出最佳的溶胀工艺为:m_(废旧面料)∶m_(DMSO)=1∶10,溶胀时间40 min,溶胀温度90℃。在该工艺下对织物进行溶胀处理,得到织物的质量损失率为3.06%,K/S值为16.906。  相似文献   
5.
The aim of this paper was to predict the colour strength of viscose knitted fabrics by using fuzzy logic (FL) model based on dye concentration, salt concentration and alkali concentration as input variables. Moreover, the performance of fuzzy logic (FL) model is compared with that of artificial neural network (ANN) model. In addition, same parameters and data have been used in ANN model. From the experimental study, it was found that dye concentration has the main and greatest effects on the colour strength of viscose knitted fabrics. The coefficient of determination (R2), root mean square (RMS) and mean absolute errors (MAE) between the experimental colour strength and that predicted by FL model are found to be 0.977, 1.025 and 4.61%, respectively. Further, the coefficient of determination (R2), root mean square (RMS) and mean absolute errors (MAE) between the experimental colour strength and that predicted by ANN model are found to be 0.992, 0.726 and 3.28%, respectively. It was found that both ANN and FL models have ability and accuracy to predict the fabric colour strength effectively in non-linear domain. However, ANN prediction model shows higher prediction accuracy than that of Fuzzy model.  相似文献   
6.
BACKGROUND: Disintegration was developed as a pretreatment process for sludge to accelerate the digestion processes. Ultrasonic treatment may be a good alternative for sludge disintegration. In this study, different specific energy inputs ranged between 0 and 15 880 kJ kg?1 and very low ultrasonic densities ranged between 0.04 and 0.1 W mL?1 were applied to biological sludge for disintegration purposes. The potential for improving anaerobic digestion through ultrasonic pre‐treatment and the effect of ultrasonic pre‐treatment on the filterability characteristics of sludge were also investigated. RESULTS: 9690 kJ kg?1 TS of supplied energy and very low power density of 0.09 Wm L?1 are efficient for floc disintegration. For 9690 kJ kg?1 TS, 44% higher methane production was achieved than with raw sludge as a result of biochemical methane potential assay. The supernatant characteristics of the sludge were also affected by the ultrasonic pre‐treatment. For 9690 kJ kg?1 TS, the soluble chemical oxygen demand (SCOD), dissolved organic carbon (DOC), total nitrogen (TN), and total phosphorus (TP) in the sludge supernatant increased by 340%, 860%, 716%, and 207.5%, respectively. CONCLUSION: Ultrasonic pre‐treatment is an effective method for biological sludge disintegration even at very low ultrasonic density levels. It leads to increased anaerobic biodegradability but deteriorates the filterability characteristics of biological sludge. Copyright © 2009 Society of Chemical Industry  相似文献   
7.
BC6下支承钢领、钢丝圈的使用结果证明,能够满足粘胶系列产品的生产需要,成纱质量。布面质量有所提高,断头降低,捻度均匀,毛羽、棉球有所减少。  相似文献   
8.
根据粘胶纤维生产的特点,利用制冷压缩机产生的压缩热优化设计粘胶纤维厂制冷系统。该制冷系统是先将制冷压缩热作为包装箱烘干线的热源进行第一次利用,其加热的软水进行第二次利用。该制冷系统取消了常规设计中的冷却系统设备。结果表明:粘胶纤维厂制冷系统采用这种优化方法,制冷系统压缩热有效利用率达53%,节电12.5%,相当于制冷系统能耗减少60%以上。  相似文献   
9.
氨纶纺丝熔体的流变行为   总被引:2,自引:0,他引:2  
笔者应用毛细管流变仪研究了自制熔纺氨纶切片的流变行为,探讨了熔体表现粘度、非牛顿指数、结构粘度指数、表观粘流活化能等流变特性与温度及剪切速率的关系。结果发现,氨纶熔体为切力变稀流体,其非牛顿指数随温度的升高而增大,在210℃时达到最大值。结构粘度指数随温度升高而下降,在210℃时达到最小值,说明在此温度下熔体的可纺性最好。溶体表观粘度与温度的相关性显著,并且随着剪切速率的增大,聚氨酯熔体的粘流活化能减小。  相似文献   
10.
黏胶纤维酶水解反应工艺研究   总被引:2,自引:0,他引:2  
将黏胶纤维水解成糖类物质,是利用废弃黏胶纤维制备燃料乙醇的关键步骤.采用正交试验的方法,对纤维素酶催化黏胶纤维水解反应中的主要因素的影响进行了综合研究.结果表明,影响因素的显著性大小依次为:催化剂用量、固-液比、温度、pH值.对反应时间、温度、催化剂用量等影响因素进行的详细研究结果表明,酶的用量适当,反应温度选择在纤维素酶的适用温度上限,反应时间约为2 h是比较适宜的反应条件,黏胶纤维水解率约达87%.  相似文献   
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