超声波清洗在核设备去污中的应用

介绍了核工业设备去污过程中常用的清洗方法,超声波清洗的原理及其在核工业设备去污中的应用,超声波去污存在的问题.通过建立试验模型,探讨了清洗时间、清洗温度和超声波功率密度对清洗效果的影响,展望了核设备超声波清洗的前景和研究方向.     

合成引发剂技术在聚合装置上的应用

介绍了釜内直接合成引发剂的生产过程及影响合成引发剂收率的因素。该工艺合成的引发剂是在釜内由CatC(氯甲酸乙酯 )、CatD(双氧水 )、CatE(氢氧化钠 )进行反应生成的过氧化物EHP。该引发剂是直接合成的 ,不存在诱导期 ,聚合反应速率平稳。其成本为 5 .95元 / (t·PVC) ,远低于配制的引发剂 ,这也代表着过氧类引发剂的另一种使用方法 ,具有广泛的市场前景。     

Application of pulse detonation technology for boiler slag removal

Pulse detonation technology for removing slag and fouling deposits in coal-fired utility power plant boilers offers great potential. This technology offers a potentially convenient, inexpensive, yet efficient way for on-line slag removal. This paper presents a feasibility study that includes both Computational Fluid Dynamics (CFD) simulations and laboratory experiments. CFD simulations provided visual and quantitative data to study the potential mechanisms for removal of slag. Mechanisms included direct impact, flow scrubbing, wave reflection and negative velocity impact on the back side of the tubes. Several experiments were carried out to verify the potential of the pulse detonation technology. Experiments were done using a pulse detonation engine and heat exchanger tubes with different types of slag placed in different orientations on the tubes. Tubes were placed at various distances from the detonation tube and in different configurations. The results present a strong case for the application of this technology for online slag removal. It is especially effective for removal of slag on the back sides of the tubes where other traditional methods are not very successful. A preliminary cost analysis indicated that the technology can be paid for within the first year itself and provide substantial savings in the subsequent years.     

干法乙炔生产装置设备的应用与改造

概述了干法乙炔生产工艺。介绍了干法乙炔生产装置中4种重要设备(发生器、锤式破碎机、斗提机及管状带式输送机)的工作原理及结构特点,分析了其在运行过程中出现的问题,并进行了相应改造,效果良好。     

化学清洗在轻烃装置铝翅片空冷器的应用

分析了影响中原油田天然气处理厂铝翅片空冷器散热的因素,提出了解决问题的办法,通过实施使用化学清洗液清洗空冷器这一方案,有效的提高了空冷器的换热效率,延长空冷器的使用寿命,经济效益显著,达到清洁生产、节能降耗的目的。     

Bubble detonation in polydisperse media

Detonation waves in polydisperse bubble media have been studied experimentally. Data on the critical initiation conditions and on the structure and properties of detonation waves were obtained. The characteristics of detonation waves in poly- and monodisperse media were compared. The behavior of gas bubbles with various diameters in the detonation wave have been investigated. Lavrent’ev Institute of Hydrodynamics, Siberian Division, Russian Academy of Sciences, Novosibirsk 630090. Translated from Fizika Goreniya i Vzryva, Vol. 33, No. 3, pp. 114–119, May–June, 1997.     

Structure of detonation waves in PETN

A VISAR technique was used to study the structure of the reaction zone in PETN for various initial densities and dispersion of samples. The flow in the pressed charges corresponds to the classical denotation model. In the case of bulk density, the peculiarities corresponding to an explosive combustion model are recorded. In the vicinity of the initial density of 1.7 g/cm³, a kink is found on the curve showing detonation velocity versus density, and the shock-wave initiation of PETN above and below the kink point is studied.     

Bifurcation structures in gas detonation

The possibility of existence of two-scale (bifurcation) structures of detonation in ammonia-oxygen, ammonia-air, and ammonia-nitrous oxide mixtures with wide-range variations of the initial parameters is analyzed. It is established that ammonia-oxygen mixtures are characterized by a classical irregular structure. Bifurcation properties are manifested if nitrous oxide or hydrogen peroxide is added. This shows that systems with bifurcation properties have certain flammability limits in terms of fuel, which are responsible for the multiscale character of the structure. The critical diffraction diameter of the detonation wave with bifurcation properties in mixtures close to a stoichiometric composition depends on the greater cell size; the presence of small-scale cells and additional “hot spots” at the points of collisions of transverse waves does not lead to any noticeable improvement of initiation. This fact contradicts the “hot spot” hypothesis, which implies that detonation initiation is facilitated if a greater number of “hot spots” are available.