杜邦干热拉伸工艺对涤纶短纤维干热收缩率的影响

通过后加工工序的优化来降低1.33 dtex×38 mm涤纶短纤维的180℃干热收缩率。指出:合适的紧张热定型温度、冷却和松弛热定型的烘燥效果可以降低该纤维的干热收缩率。     

降低涤纶短纤维180℃干热收缩率的工艺探讨

本文对影响涤纶棉型短纤维180℃干热收缩率的工艺因素作了探讨。指出紧张热定型的穿丝方式、加热时间和温度是影响180℃干热收缩率的主要因素。松弛定型在紧张定型效果不强烈的情况下,也可使干热收缩率降低,且紧张和松弛定型均可使纤维结晶度变化。采用紧张辊面温度为185℃,紧张五、八辊全穿,较低松弛定型温度的生产工艺,可得到180℃干热收缩率为7—8%,断裂强度5.48cN/dtex,断裂伸长19—24%的高强低伸棉型纤维。     

涤纶短纤维干热收缩率测试影响因素探讨

根据生产应用与测试实践,对涤纶短纤维干热收缩率测试过程中前处理烘箱的功率、样品处理后冷却条件,烘箱鼓风功能使用几种影响因素进行了实例应用说明.     

降低油毡基布用涤纶短纤维干热收缩率的工艺探讨

主要讨论了通过后加工工序来降低2.78dtex×65mm油毡基布用涤纶短纤维的180℃干热收缩率。指出:提高拉伸倍率、合理进行倍率分配,提高定型温度、延长定型时间,降低五辊定型机(HR)与第三拉伸机(DF-3)速度比可以降低该纤维的干热收缩率。     

帘线干热收缩测试仪

介绍GRS-2型帘线干热收缩测试仪的原理、结构、技术参数及操作方法。该机采用进口温控器和高精度传感器，数据采集模块与计算机相连，可测试纤维帘线在一定温度下的收缩率和收缩力，在测试过程中可实时显示帘线的收缩率或收缩力值及曲线，并将各项参数和测试结果保存为数据库，以便用户存档和打印各种报表，测试简单方便且稳定可靠。     

高强低伸低干热有光缝纫线用涤纶短纤维影响因素研究

现有的1.33 dtex有光缝纫线用涤纶短纤维断裂强度、断裂伸长率和干热收缩率不能满足用户需求。对不同负荷和纺丝速度、冷却空气吹出距离、聚酯熔体特性黏度和拉伸倍率等加工工艺的调整优化,对三项质量指标进行试验,结果表明:提高纺丝相对速度、降低冷却空气吹出距离、适当降低熔体特性黏度并提高拉伸倍率、降低回缩倍率可以在直接纺生产高强、低伸、低收缩第三代有光缝纫线用涤纶短纤维。最终产品断裂强度6.55 cN/dtex,断裂伸长率20.6%,干热收缩率2.5%。     

低熔点皮芯复合聚酯纤维干热收缩研究

为了降低低熔点皮芯复合聚酯纤维的干热收缩,提高尺寸稳定性,采用干热收缩测试仪和声速取向测量仪研究了低熔点皮芯复合聚酯纤维的收缩机理以及纺丝成形和牵伸工艺对干热收缩率的影响规律。结果表明降低纺丝速度、升高牵伸温度、降低二牵倍率分配比例,有利于降低纤维干热收缩率。通过工艺调整,降低了低熔点复合纤维干热收缩率。     

纺速对聚酯工业丝干热收缩率的影响

通过对不同纺速的高粘聚酯初生丝的结构的测试,探讨了初生纤维结构随纺速变化的规律,以及初生丝的结构对成品工业丝的干热收缩率的影响。     

用于防水卷材基布的涤纶短纤维的生产

讨论了在HV452型纺丝机上采用2808孔喷丝板生产用于防水卷材基布的涤纶短纤维的生产工艺,指出提高成品纤维的强度、断裂伸长率、降低干热收缩率是满足防水卷材基布性能要求的关键。     

涤纶短纤维干热值超标的原因分析及对策

分析了短纤维干热值超标的原因,提出了调整丝束密度和优化速比分配等对策,并取得了良好效果。     

利用热泵干燥污泥技术的试验研究

为了对热泵干燥污泥的方法进行研究,采用自行设计的污泥热泵干燥装置对含水率为55%-60%的污泥进行干燥试验研究。分析了风量、空气参数、冷凝温度和蒸发温度等对干燥效果的影响。试验表明,风量、空气参数、冷凝温度和蒸发温度对干燥效果有较大的影响,随着风量的增大,出水量逐渐增多,在风量达到800-1000m3/s,达到一个最佳的干燥效果,此时能耗比为0.73。     

Heat and Mass Transfer Modeling of Apple Slices Under Simultaneous Infrared Dry Blanching and Dehydration Process

To develop a new simultaneous infrared dry blanching and dehydration process for producing high-quality blanched and partially dehydrated products, apple slices with three different thicknesses, 5, 9, and 13 mm, were heated using infrared for up to 10 min at 4000 W/m² IR intensity. The surface and center temperatures, moisture change, and enzymatic activities of polyphenol oxidase (PPO) and peroxidase (POD) of apple slices were determined. The models of heat and mass transfer and enzyme inactivation were developed for predicting the blanching and dehydration performance. In the model development, the apple slices were assumed as one dimensional with heat and mass transfer only occurring in one direction. The enzyme inactivation followed first-order kinetics. The models were solved using a finite element method. The predicted temperature and moisture profiles and inactivation rate of enzymes were found to be in good agreement with the experimental data. This indicated that the process of simultaneous dry blanching and dehydration of apple slices under IR heating can be predicted with the developed models.     

熔渣干法粒化及余热回收技术进展

介绍了目前国内外高炉渣、钢渣等冶金熔渣处理、回收利用技术的进展,重点概述了滚筒法、风淬法、离心粒化法等干法粒化技术的研究进展和发展趋势,并对比分析了熔渣各种干式处理工艺的优点和不足;介绍了物理法、化学法两种熔渣显热回收途径。最后得出结论:离心粒化法的粒化及显热回收效果最好,将是熔渣回收和利用的主流工艺。     

多级干燥装置废气余热的利用

本文对三级流化床干燥装置的废气余热提出了两种余热利用方案。由计算结果和系统分析表明,尽可能充分篮产高品位的废气,更有利于装置热效率的提高和系统优化。     

Calculation of the Heat Transfer in Coke Dry Quenching by Numerical Modeling

The air flow and heat transfer in a coke dry quenching (CDQ) system are analyzed by simulation using FloEFD software, within the framework of a modified k–ε model of turbulence. The calculated temperatures are compared with operational data. The accuracy of the simulation is acceptable. The proposed method may be used for engineering calculations in the design and refinement of CDQ systems or their components, with significant decrease in experiment costs.     

The Structural Causes of the Dyeing Variations of Nylon Yarns Subjected to Dry Heat

When nylon 6 and nylon 6.6 yarns are subjected to dry heat in a texturing machine, the subsequent rate of dyeing with Durazol Blue 2R at first falls and then increases with increasing temperature of heat treatment. It becomes greater than that of the unheated yarn for samples that have been preheated to temperatures near the melting point of the nylons. It has been shown that Fick's law is valid for nylon 6.6 dyed with Durazol Blue 2R in an infinite dyebath. This does not hold for nylon 6, so that, in consequence, for characterising the dyeing process for both nylons the rate of dyeing is a better parameter than the diffusion coefficient. Measurements of density, birefringence, and degree of lateral order by an X-ray method show that these are all increased by the heat treatments. The moisture regain is, however, decreased, but little change is produced in the amine end-group content and X-ray orientation in the samples. An explanation of the dyeing results in relation to the physical and chemical changes is advanced. A morphological structure is envisaged of long ribbon-like units held together by binding material that allows an increase in the relative size of voids, or the total void content, on heating the nylons above a certain temperature, this temperature depending on the particular nylon.     

复合式干法洗煤在尚庄煤业的使用

利用复合干法洗煤技术,对劣质煤进行洗选粗加工、排矸、降硫,提高发热量,用最合理、经济的生产成本,使劣质原煤通过干法洗选加工后,既满足销售市场对煤质的基本要求,同时又为企业创造可观的经济效益。     

用制磷电炉电极直接烘炉剖析

剖析了传统烘炉方法存在的问题,阐述了制磷电炉的电极材料碳和石墨的存在形式和性质、烘炉烧结的作用和要求,分析了烘炉烧结的影响因素,介绍了电极直接烘炉的操作步骤。指出采用电极直接烘炉工艺具有操作简单、灵活,烘炉周期短、质量高,热利用率高等优点。     

复合固化吸附储氢材料的传热性能测试及仿真

针对目前金属氢化物储氢技术中面临的粉化后传热性能不佳等问题,采用膨胀石墨为基质配制固化的金属氢化物吸附剂。使用Hotd isk热物性分析仪,测试了固化吸附剂的热物性参数,并对固化吸附床的传热及相应的储氢特性进行了仿真。研究结果表明,固化混合吸附剂相对于散装的储氢合金,轴向导热系数最高提高了52倍左右,径向导热系数最高提高了12倍左右。通过仿真发现,在相同的80℃热源温度下,固化混合吸附床所需要的加热时间相对于散装储氢合金吸附床可以缩短17%,吸氢速率可以提高24%。