Sizing of Packed Deaeration Columns

Removal of oxygen from feedwater is of paramount importance for safe boiler operation. Insufficient extraction of oxygen in deaeration vessels will lead to limited efficiency of oxygen scavengers and unsafe plant operation. The presented sizing procedure for packed deaeration columns is based on the similarity theory between heat and mass transfer and existing procedures. The goal of the proposed technique is not to achieve optimization of column dimensions, but to ensure that there is no undersizing of the packing height. This approach is justified considering the relatively low capital costs of deaeration columns in boiler plants. The proposed equations are based on an experimental setup involving several hundred operating regimes which have been verified and confirmed to have a high degree of accuracy.     

高压模块的有机硅凝胶灌封工艺设计与改进

介绍了某高压模块产品灌封工艺技术。该高压模块主要由多级倍压整流电路组成,要求具有良好的绝缘、抗振及三防特性,因此采用一体化(即模具作为结构支撑件)的灌封结构设计,以实现小型化、模块化。针对高压模块的灌封要求,选用合适的灌封材料;并针对灌封中出现的问题,通过原因分析找相应问题的解决办法,然后对高压模块灌封工艺进行改进。根据几批次高压模块的试验结果,该灌封工艺技术满足模块的设计要求。     

Comparison of two headspace solid phase microextraction fibres for the detection of volatile chemical concentration changes due to industrial processing of orange juice

Solid phase microextraction (SPME) with two polymeric coatings, polydimethylsiloxane (PDMS) and polyacrylate (PA), was used to isolate and quantitate orange juice volatile compounds from the headspace of fresh orange juice after the finishing, deaeration and pasteurisation processes. The results from the two fibres were largely consistent. Statistically significant changes in concentration due to the deaeration process were detected for medium‐volatility alcohols, hexanal and seven terpenes as measured by SPME‐PDMS. However, when using the PA‐coated fibre, more statistically significant changes in concentration were detected for aldehydes and esters. Alcohols and terpenes presented similar results using both polymeric coatings. The pasteurisation process did not modify the aromatic profile of the deaerated orange juice, except for methyl butyrate. These results indicate that the PA coating seemed to be more suitable for the analysis of the evolution of the orange juice aromatic fraction during industrial processing. Copyright © 2005 Society of Chemical Industry     

600MW机组旋膜式除氧器的设计开发

国内大型电站的除氧设备多数采用无头除氧器,除氧核心部件依赖进口,价格偏高,也使除氧器的国产化率得不到提高。我公司自主研发的旋膜喷管已成功应用于300MW机组的旋膜式除氧器产品,在电站行业得到普遍推广使用,市场前景较好,为了不断创新和加深设计开发,文章介绍旋膜喷管在大型600MW机组中的应用。     

热力除氧辅助化学除氧技术的工业应用

介绍了云南云天化国际化工股份有限公司云峰分公司硫酸厂废热锅炉给水热力除氧系统存在的问题和改进措施。采用热力除氧辅助二甲基酮肟法化学除氧后,除氧水ρ(O2)≤0.015 mg/L,200 kt/a和300 kt/a硫酸装置锅炉水指标均达到正常生产要求。今后可考虑将热力除氧温度降低6～7℃,综合除氧成本将降低0.6元/t,预计改进后硫酸厂每年可节省运行费用约63万元。     

热力除氧系统的计算机控制

介绍了某炼油厂除氧系统计算机控制系统的结构组成、控制功能和特点,设计了耦合系统的模糊控制叙述了压力和水位的控制方案和控制软件,该系统投入运行以来,效果良好。     

浅谈混凝土结构胶的成型对其性能检测的影响

探讨混凝土结构加固用胶性能试验中成型因素对检测结果的影响,试验过程采用统一的打磨方式、养护条件、脱模方法、胶体厚度、夹持方式等,建议采用经过真空脱泡处理和垂直灌注成型技术来提高结构胶的性能。     

锅炉给水除氧技术的发展与应用

阐述锅炉给水除氧的途径及方式，并进行经济比较，企盼探索适用一般工业锅炉房的经济实用的给水除氧方法。     

烧结式微热管的工质灌注、抽真空与封接

目前微电子与光电子芯片对散热要求日益增高,烧结式微热管已经成为其理想的散热元件,对微热管进行快速抽真空,使微热管中的工质量与真空度符合要求,是决定其制造质量与成本的重要因素。通过对微热管的工作原理及其抽真空-工质灌注-冷焊的制造方法进行分析,提出一种分别采用工质冻结-抽真空-冷焊法与二次除气-冷焊法对烧结式微热管进行抽真空的方法。大量的实验表明,采用所提出的制造方法不仅可以保证微热管中工质量与真空度达到要求,而且抽真空的时间大约比原有方法节省了2/3,具有很好的传热性能。     

工业锅炉能效及其计算方法

本文提出工业锅炉能效的定义及能效计算方法，就国内关于锅炉净效率的计算方法作了归纳，然后通过两个计算示例对工业锅炉热效率、净效率和能效的计算方法及相互关系进行分析讨论，得出几点结论意见