现场总线技术在非能动压水堆核岛中的应用

本文结合非能动压水堆核电控制系统结构,详细介绍Profibus现场总线和Modbus现场总线在非能动压水堆核电控制系统中的应用,包括两种现场总线技术的结构配置及和现场智能仪控设备的连接,并简要分析现场总线技术在核电行业应用的优点和需克服的技术问题。     

OXIDATION OF SULFUR DIOXIDE IN DIFFERENT TYPES OF THREE PHASE REACTORS

Five different types of three-phase reactors are compared with each other by using oxidation of sulfur dioxide on activated carbon. The kinetic measurements were carried out by changing concentrations of sulfur dioxide from 0.04 to 0.17% (volume) and those of oxygen from 2 to 21%. The reaction rate was 0.2 order with respect to sulfur dioxide and 0.5 order with respect to oxygen. The catalytic effectiveness factor and intraparticle diffusivity were evaluated by changing particle sizes of activated carbon from 0.03 to 1.6 mm. Resistances of gas-liquid, liquid-solid mass transfer and intraparticle diffusion were estimated for individual reactors. The optimum reactor was dependent on operating conditions such as gas flow rates, rotating speeds and particle sizes.     

水合肼生产中氧化反应的研究和应用

分析了尿素法生产水合肼的氧化反应历程及影响因素，改进了反应器，并找到了最佳的工艺控制条件：①控制n(尿素)：n(次氯酸钠)=(1．05～1．10)：1，各原料的消耗较低，总经济效益佳；②采用-5℃冷冻盐水移走尿素、次氯酸钠混合段内氯化反应放出的热量，控制物料混合终点温度在15～30℃；③采用列管式加热器，将氯化反应与水解反应在不同的设备中进行，水合肼的收率提高到83％～85％；④采用列管式加热器代替双夹套反应器，提高了加热强度，生产能力大，1套合成反应器可生产1万t／a80％的水合肼。     

Control policies for an industrial acetylene hydrogenation reactor

This paper addresses the problem of finding optimal operational policies for an acetylene reactor for day to day operation. A lumped parameter model based on four main reactions is developed and used to examine the effects of the reactor manipulated variables on key reaction parameters. An optimal and a sub-optimal operational policy which minimize the ethylene loss over time are formulated and the solution techniques are presented. The results indicate that the reactor model is in good agreement with industrial plant data. The performance of the optimal control policy is very similar to the performance of the sub-optimal control policy. However, the sub-optimal formulation, while retaining the dominant features of the optimal response, reduces the computational requirements. Finally, some issues concerning the real-time implementation of an advanced acetylene reactor control scheme are presented. These include the estimation of the optimum regeneration cycle, a recursive model update algorithm, the process optimizer and their overall coordination. A preliminary analysis of the benefits associated with the advanced control scheme suggests a considerable reduction in the yearly ethylene loss.     

生物浸矿反应器的制作及矿浆质量分数分布特征

以自制的生物浸矿反应器为对象,以反应器内矿浆质量分数分布为评价指标,就搅拌器搅拌方式、外循环流量及曝气大小对矿浆质量分数的分布进行了研究.结果表明:当搅拌速度为1800～2000 r/min,搅拌桨离曝气器顶部2～3 cm,外部循环流量为13 L/min,曝气量为1.2 m3/h时,反应器内矿浆质量分数分布均匀.并对总矿浆质量分数为6 %、10 %、15%和20%的反应器内矿浆质量分数随反应器高度的变化进行了研究.     

延长生焦时间对延迟焦化装置的影响

国内焦化装置的生焦时间几乎都采用24小时，设计的焦炭塔空高较大，在装置低负荷生产时，适当延长生焦时间，不仅可降低装置的运营成本、提高焦炭质量、降低劳动强度，而且还可降低维修费用。安庆焦化成功地在一套装置上实现了48小时生焦操作，年运行200天，增效约100万元。     

熔盐堆临界能谱与通量分布的仿真计算

研究熔盐反应堆在临界工况下的堆芯中子能量和中子通量分布.由于熔盐反应堆的几何结构与目前的热中子反应堆存在很大差异,导致热中子反应堆能谱的求解方法在对熔盐堆进行计算时存在几何处理上的困难.针对上述问题,提出采用具有任意几何处理能力的中子输运计算软件MCNP对熔盐堆堆芯结构进行建模,采用能量区间上的平均通量代替该区间内通量分布的方法,计算了两种熔盐堆在临界工况下的堆芯中子能谱.结果表明,MSBR堆芯能谱为典型的热堆能谱;MO-SART堆芯能谱介于快堆能谱和热堆能谱之间.结果能够作为堆芯扩散计算中能量分群方法的依据.同时分析了堆芯内中子通量分布情况,结果表明熔盐堆中子通量分布具有中间高、四周低的特点.     

气升式内环流反应器中油滴的分散特性

本文研究了气升式内环流反应器中油滴的分散特性。以对数正态分布密度函数为油滴尺寸的分散模型,导出了油滴的Sauter平均直径解析式。对模型作了实验验证,关联了模型参数。提出了油滴的尺寸分布密度函数和Sauter平均直径的半经验式。结果表明计算值与实验值吻合良好。     

Research on graphite powders used for HTR-PM fuel elements

Different batches of natural graphite powders and electrographite powders were characterized by impurity, degree of graphitization, particle size distribution, specific surface area, and shape characteristics. The graphite balls consist of proper mix-ratio of natural graphite, electrographite and phenolic resin were manufactured and characterized by thermal conductivity, anisotropy of thermal expansion, crush strength, and drop strength. Results show that some types of graphite powders possess very high purity, degree of graphitization, and sound size distribution and apparent density, which can serve for matrix graphite of HTR-PM. The graphite balls manufactured with reasonable mix-ratio of graphite powders and process method show very good properties. It is indicated that the properties of graphite balls can meet the design criterion of HTR-PM. We can provide a powerful candidate material for the future manufacture of HTR-PM fuel elements.