煤气化产生的有机物对尿素产品颜色的影响

我公司有两套设计能力为110kt／a的尿素生产装置。原采用重油气化制气，2000年改用富氧煤气化技术，用高热值的白煤和焦炭制气；2003年因白煤和焦炭涨价，煤源紧张，又改为投资少、以煤源充足的廉价劣质煤为原料的恩德粉煤气化工艺制气。净化工序采用NHD脱碳工艺。目前恩德粉煤气化工序和净化NHD脱碳工序运行稳定，企业效益可观，但尿素产品变色的问题一直未得到有效解决，影响了尿素产品的质量。     

尿素水解制氨系统问题分析与对策

各地煤电企业积极开展尿素替代液氨的升级改造工作，以某电厂为例总结了2×350 MW机组脱硝系统采用尿素水解制氨工艺现场实际运行案例，阐述了制氨系统中尿素水解用蒸气系统、尿素溶解系统及水解器运行过程中关注重点，分析了尿素水解制氨系统运行过程中检查发现的供氨管路堵塞、阀门腐蚀及水解器加热盘管点蚀等缺陷问题，通过对尿素水解系统运行原理、产品气回凝腐蚀机理及水解器盘管和筒体腐蚀机理研究和分析，提出系统运行时优化解决方案。运行中应提高产品气的运行温度，降低回凝腐蚀产生的可能性，且改造后水解供氨系统运行稳定，极大提高了尿素水解系统及脱硝装置的运行安全性和可靠性；由于氯离子来自尿素，应加强水解器排污，缓解氯离子富集，增加换热器疏水pH的检查频次，确保发现泄漏并及时更换，同时尽量采用低氯尿素或通过设备改进及投入缓蚀剂等方法降低氯离子对金属设备腐蚀。通过尿素水解制氨系统运行过程中常见异常问题分析与处置研究，为类似尿素水解制氨系统的正常运行提供借鉴。     

1999～2000年合成氨、尿素技术进展

根据１９９９年７月－２０００年６月国内有关合成氨,尿素工业的文献报道,对合成氨原料气的净化、制气、变换、氮合成,尿素各工序的研究成果,技术等进行了全面的介绍,反映了我国１９９９－２０００年合成氨和尿素工业的技术进展情况。     

2000—2001年合成氨、尿素技术进展

根据2000年7月－2001年6月国内有关合成氨、尿素工业的文献报道,对合成氨原料气的制气、净化、变换、脱碳、氨合成、尿素各工序（包括工艺、设备、控制、催化剂等）的研究成果、技术等进行了全面的介绍,反映了我国2000－2001年合成氨和尿素工业的技术进展情况。     

焦炉气常压非催化转化制合成气技术的应用

1概述平顶山飞行化工公司年产合成氨180 kt,尿素300 kt,每年要耗用大量的煤、焦制合成原料气。因煤、焦价格持续上涨,生产成本不断增大,严重影响了企业的经济效益和持续稳定发展。而紧邻我公司的平顶山天宏焦化公司是年产1 300 kt焦碳的大型焦化企业,每年副产4×108m3焦炉气,除     

合成氨,尿素技术进展

根据１９９８年７月～１９９９年７月国内有关合成氨、尿素工业的文献报道，对合成氨原料气的净化、制气、变换、甲烷化、尿素各工序（包括工艺、设备、控制、催化剂等）的研究成果，技术革新等进行了全面的介绍，反映了我国１９９８～１９９９年合成氨和尿素工业的技术进展情况。     

自气提一分塔与CO2气提塔的比较

随着尿素装置的扩产改造，国内很多尿素企业对水溶液全循环法尿素装置的预精馏塔与一分加热器进行改造，改为自气提式一分塔。由于水溶液尿素装置的局限性，不少企业在新建尿素生产装置时选择CO2气提法。水溶液全循环法的自气提一分塔与CO2气提塔在结构上较为相似，但在生产原理、操作以及设备的安装等方面都有很大区别。     

我公司联醇生产小结

我公司原是以块煤为原料,采用固定层间歇气化制气的小氮肥企业,通过近几年的扩产改造,现已达到年产合成氨15万t(联产甲醇）,尿素25万t的生产能力。     

脱硫系统节能降耗改造

宁夏丰友化工股份有限公司以无烟煤为原料生产尿素,合成氨生产采用常压固定层间歇式造气炉制气、常压脱硫、加压ADA变换脱硫、醇烷化精炼工艺,尿素生产采用水溶液全循环工艺。     

恩德炉纯氧造气实验小结

我公司拟在内蒙古呼伦贝尔市建一套甲醇装置，采用恩德粉煤气化技术生产甲醇原料气。为验证恩德粉煤气化炉纯氧制气生产甲醇合成原料气的可行性，2005年7月，公司利用现有尿素系统造气装置的2台恩德炉，分别用内蒙古免渡河长焰煤、大雁褐煤进行了纯氧制气实验，取得了良好的效果，现把实验情况总结如下。     

民用工业中复合材料桁架的应用和发展

本文叙述了复合材料桁架的构造、分类和计算方法,突出了复合材料桁架的优越性能和在民用工业中的应用前景;在分析大量文献资料的基础上阐述复合材料桁架杆件的多种加工工艺,并比较不同截面形式对杆件性能的影响;探讨复合材料杆件的破坏机理和分析方法,介绍节点的类型和各自的特点,提出节点及连接部位存在的关键问题;根据国内外复合材料桁架的研究和应用现状,阐述了复合材料桁架的性能和不同的设计方法,总结归纳影响复合材料桁架性能的关键因素和设计中存在的一些问题,并提出改进杆件设计、节点设计和优化复合材料桁架的建议。     

颗粒介质用机械密封热力耦合变形及摩擦磨损研究

在含有颗粒介质的工作环境中下,硬质材料配对机械密封环的热力耦合变形和摩擦磨损对机械密封的泄漏和使用寿命起着至关重要的作用。考虑动静环和颗粒介质的摩擦,试验测定了摩擦系数,建立了动静环热力耦合的有限元计算模型,研究了WC-Co硬质合金和无压烧结碳化硅（SSiC）陶瓷两种硬质材料密封的温度场和端面变形规律,分析了不同工况下的密封间隙变化规律。试验测试分析了密封环温度、磨损前后的泄漏及表面粗糙度,讨论了端面的磨损机理,验证了计算模型的准确性。结果表明：考虑动环磨粒摩擦热的有限元模型能准确地预测密封的温度和端面变形;耦合作用下动静环端面呈现外径脱离、内径贴合的变形,且变形差异程度随压差和转速的增大而加剧;变形导致端面磨痕分布不均匀,内径磨痕较严重。WC-Co硬质合金配对密封环的端面变形小、泄漏量小,高硬度WC颗粒对Co基体能产生很好的“阴影效应”,具有良好的耐磨粒磨损性能。SSiC陶瓷材料韧性差,易产生片状磨屑,形成过渡型磨粒磨损,材料耐磨性较差,泄漏量增加明显。在磨粒工况下,WC-Co硬质合金机械密封具有泄漏小、耐磨性强的特点。研究结果为颗粒介质中机械密封的材料应用及设计优化提供了参考。     

Environment and colour: The technological interface

Technology and colour are viewed as interfaces between the environment, humans and human activity. Examples are provided of ways of facilitating and improving access to and use of colours by commercial users of colour coatings through improvements in the accuracy of measuring and displaying colour. By analogy, the task of providing effective interfaces within the coatings industry, between the coatings industry and the environment and between the coatings industry and the public and political domain are discussed. Examples of information shortfalls are cited to illustrate how distortions arise. Examples of more effective, integrated technological, organisational and political interfacing are culled from the author's experiences.     

木质纤维生物质半纤维素分子模拟应用研究进展

木质纤维生物质资源是重要的可再生生物质资源,主要包含纤维素、半纤维素和木质素。半纤维素含量仅次于纤维素,是一种丰富、可再生的植物资源,其可水解制备重要化学品以及改性制备多功能材料。本文综述了生物质半纤维素分子模拟应用研究进展,从半纤维素大分子形态及其与纤维素结合方式的分子模拟研究和半纤维素制备化学品及材料的分子模拟研究2个方面进行阐述,从模拟结果可以看出半纤维素在细胞壁中与纤维素和木质素的相互作用及其本身的大分子形态对木质纤维生物质三大素的提取利用具有显著影响。分子模拟有利于理解过程机理,对反应效率的提高具有重要理论指导意义。最后对分子模拟在半纤维素研究的发展应用进行了展望,指出目前半纤维素分子模拟的空白领域,主要包括半纤维素液化生产生物油、木糖异构化生产木酮糖、半纤维素与木质素之间的结合方式以及其他的半纤维素基材料等,这些有待进一步的探索与研究。     

可生物降解分离膜材料及其应用研究进展

在绿色化学理念的引导下,可生物降解膜材料受到了广泛的关注,有望成为传统分离膜材料的补充和替代品。本文首先分析了传统的不可降解分离膜材料的现状及问题,然后综述了当前较为热门的几种可生物降解膜材料,讨论了它们的发展状况,详细介绍了它们在膜相关领域中的应用,并针对它们的局限性做出了说明并提出了一些解决方案。随后,分析了可生物降解膜材料的生物降解机理,从分子结构角度对膜材料的可生物降解性进行了说明,这将有利于剖析膜材料生物降解的本质,进而平衡膜材料在使用中的稳定性和生物降解性。最后,文章对可生物降解膜材料在发展中遇到的问题进行了展望,并指出随着研究的不断深入,可生物降解膜材料具有广阔的前景和深远的现实意义。     

Lipid distribution on textiles in relation to washing with lipases

Effectiveness of lipase in detergency was studied using three test soils (lard, artificial sebum, and olive oil) on a woven cotton fabric. Distribution of oily soil on fabrics was determined for three different treatments (unwashed, washed with detergent without lipase, and washed with detergent plus lipase). Osmium tetroxide was used to label lipid soil for analysis in the scanning electron microscope. Both longitudinal and cross-sectional backscattered electron images for unwashed samples showed that soil was present on surfaces of the cotton fibers and in interfiber spaces of the yarn bundle. Lard soiled samples had large deposits on the fabric surfaces, while artificial sebum and olive oil appeared more uniformly distributed throughout the textile. Oil was deposited in the interfiber capillaries of the yarn bundle and in the crenulation, secondary walls, and lumen of the fibers. Energy dispersive X-ray microanalysis was used to determine relative concentrations of oil at selected morphological locations within the fiber structure and at the fiber surface. Soil distributions within the fibrous structures differed with type of soil and laundry treatment. Backscattered electron images dramatically demonstrated the effect of lipase on cleaning. After washing with detergent plus lipase, yarn surfaces had much less residual soil; residual soil that remained was in the irregularities of the cotton fiber surfaces. Concentrations of oil in the secondary walls, crenulations, lumen, and the fiber surfaces were lower after lipase treatment for all three soils. While washing with detergent removed soil from the yarn and fiber surfaces and the crenulation of the cotton fiber, only the samples washed with detergent plus lipase had lower concentrations of soils within the secondary wall and lumen of the cotton fibers. Fabrics soiled with olive oil and washed with detergent plus lipase had the lowest concentrations of residual soil across the textile structure; the residual soil observed was mainly in the irregularities on the fiber surfaces.     

COMBINED INNOVATIVE HEAT PUMP DRYING TECHNOLOGIES AND NEW COLD EXTRUSION TECHNIQUES FOR PRODUCTION OF INSTANT FOODS

There is an increased demand for convenient foods including ready-to-eat and instant products. These products are desired with minimum concentration of synthetic chemicals. This creates challenges for the food industry and dryers manufactures to develop new technologies to process difficult-sensitive materials and to supply final products with high quality and improved properties. Fruits and vegetables are mainly composed of water, carbohydrates, proteins and lipids. Due to modification of chemical and physical bonds the compounds the material becomes viscous and sticky during processing. Conventional dryers have limitations in handling such sensitive materials. Heat pump dryers have been applied in the production of a diversity of ready-to-eat foods and dried instant products for the last five years at SINTEF-NTNU. Besides being energetically efficient and environmentally friendly, the heat pump drying technology provides a wide range of drying conditions as required to produce powders with improved characteristics. This work describes the new technologies and processing line for the production of instant foods as well as the measurements on the properties and quality attributes for raw, intermediate and final instant products.     

Mechanical Means of Enhancing Drying Rates: Effect on Drying Kinetics and Quality

The effect of various pretreatments on drying kinetics as well as quality parameters of selected vegetables and fruits was studied experimentally in a convective dryer. The pretreatments tested include application of pinholes and drilled holes of different diameters and densities, blanching and freezing. Potato, cassava, dragon fruit and red chilli were used as the sample drying materials. As expected, increase of the diameter and density of the holes under fixed drying conditions increased the drying rate. Samples with drilled holes showed better drying performance than those with pinholes. The improvement of the drying rate was found to be dependent on the physical properties and the initial moisture content of the material. Results show that the drying performance of the products that possess a skin of low moisture diffusivity, such as chilli, can be improved significantly by blanching and making perforations in the skin. Overall changes of color and volume shrinkage during drying of the samples with and without holes were similar. The effect of different modes of heat input, such as convection, conduction and radiation, on the drying performance of the treated samples was also experimentally investigated. On-off type controllers were used to regulate the power of the heaters and maintain the product temperature within a range of pre-set values. Convection combined with radiation displayed the highest drying rate.     

基于甘草配伍黄芩同时泡沫分离甘草酸和黄芩苷

为了同时分离甘草中有表面活性的甘草酸和黄芩中无表面活性的黄芩苷,开发了甘草配伍黄芩泡沫分离工艺。通过荧光光谱、紫外吸收光谱和红外吸收光谱分析表明,甘草酸与黄芩苷存在相互作用,并且甘草黄芩配伍强化了甘草酸和黄芩苷的提取。以甘草酸和黄芩苷的富集比和回收率为评价指标,当温度为40℃、气体体积流量为100 ml·min^-1、甘草酸初始浓度为0.2 g·L^-1、甘草黄芩质量比为3：1时,获得甘草酸的富集比和回收率分别为11.0和73.5%,黄芩苷的富集比和回收率分别为5.8和38.5%。通过甘草与黄芩配伍,利用泡沫分离获得黄芩中的黄芩苷。同时,与单独泡沫分离甘草中甘草酸相比,甘草酸的富集比提高了194.9%,回收率提高了23.3%。因此,甘草配伍黄芩能有效泡沫分离甘草酸和黄芩苷。     

The Influence of Temperature and Pressure During the Curing of Prepreg Carbon Fiber Epoxy Resin

The physical and hence mechanical properties of carbon fiber reinforced epoxy resin are affected by the curing conditions used in their manufacture. The relationship between the cure temperature and pressure and the density, fiber volume fraction, and the void content of cured laminates, was investigated. For the unidirectional 914C prepreg material used, an optimum cure temperature was found which gave maximum fiber volume fraction and composite density, and minimum void content. This behavior is related in the paper to resin flow and cure characteristics. A linear relationship between cure pressure and fiber volume fraction is reported and explained by reference to the void content of the laminates. It is concluded that in-house trials are required to determine the optimum size of the processing window for specific systems and components.