行列式刚性陶瓷过滤器脉冲反吹系统中的压力特性

利用高频动态压力传感器测定脉冲反吹系统中各位置的压力特性,研究了反吹压力和喷嘴孔径对压力特性的影响,提出了解决反吹不均匀的设计方案,采用过滤循环实验进行验证. 结果表明,采用相同孔径的喷嘴时,喷吹管内、喷嘴出口及过滤管内的压力特性存在较大差异,各喷嘴的反吹不均匀性随反吹压力升高而增大,反吹强度随喷嘴孔径增大而减小,喷吹管内的静压沿喷吹方向逐渐增大. 沿喷吹方向将喷嘴孔径递减能改善反吹不均匀的状况,喷嘴截面积与喷吹管截面积之比s/S对脉冲反吹均匀性的影响较大,s/S=48%~55%较佳.     

刚性过滤器脉冲反吹过程中滤管内动态压力特性

催化汽油吸附脱硫(S-Zorb)装置中反应器过滤器的脉冲反吹性能直接影响吸附剂的分离与循环。利用建立的滤管过滤性能实验装置,采用高频动态压力传感器,测定脉冲反吹过程中沿滤管长度方向不同位置处滤管内动态压力随时间的变化特性,分析了滤管长度、反吹压力和脉冲宽度对滤管内动态压力特性的影响规律。结果表明:自开口端至盲端,滤管内动态压力的压力峰值先逐渐变大后基本不变;相同反吹条件下,随着滤管长度的增加,滤管内沿长度方向各位置处的压力峰值均降低。实验范围内,1750~2000 mm滤管开口端附近的动态压力在达到压力峰值后降低为负压,并在反吹气流和脉冲压力波的共同作用下持续振荡。适当提高反吹压力以及增加脉冲宽度可以改善长滤管的反吹效果。     

陶瓷过滤器滤管脉冲反吹过程的流动特性

在由三根陶瓷滤管组成的实验装置上 ,利用热线风速仪对脉冲反吹时滤管外瞬态流场进行了测定 ,分析了喷吹压力、脉冲宽度、过滤气速和喷吹距离对滤管外流场的影响。随着离开滤管距离的增加 ,喷吹速度和回流速度逐渐减小。结果表明 ,回流现象和喷吹气流沿轴向的不均匀性是影响过滤器脉冲反吹性能的重要因素     

陶瓷过滤器脉冲反吹时滤管外压力波形的测定与分析

利用压电式压力传感器测定了滤管外的压力波形,分析了喷吹压力、脉冲宽度等因素对滤管外压力的影响。实验结果表明,在脉冲反吹时滤管外附近区域的压力波衰减轻快,而离滤管壁一定距离后压力波则在过滤器内均匀传播。同时证明在脉冲及吹过程中,集气室对相邻滤管间相互影响具有重要作用。     

陶瓷过滤器脉冲反吹系统的流场的数值模拟

In the commercial utilization of rigid ceramic filters, the performance of pulse cleaning has crucial effects on the long-term stable operation. In order to get a clear insight into the nature of this cleaning process and provide a solid basis for industrial applications, the flow in ceramic candle filter was investigated. The flow in the pulse-jetspace and inside the ceramic candle is regarded as two- dimensional, unsteady, compressible flow, and numerical simulation is carried out by computational fluid dynamics. The numerical predictions of flow field are in good agreement with the experimental measurements. Effects of the candle diameter, the separation distance between the nozzle and the candle injector and the length of the candle on the flowfield have been numerically analyzed to provide the basis for the optimum design of the pulse cleaning system.     

基于单片机的脉冲反吹控制仪设计

指出脉冲反吹技术在过滤除尘工艺中得到了普遍应用。给出了基于单片机的脉冲反吹控制仪核心电路设计方案与实现方法,并介绍了系统主要软件流程。该控制仪能实时线性调整电磁阀导通时序,测控精度高,简单实用,具有广泛应用价值。     

陶瓷过滤器脉冲反吹全过程的瞬变流场计算

采用二维轴对称非稳态流动模型对陶瓷过滤器脉冲反吹全过程中滤管内外的瞬变流场进行了数值模拟,所计算的滤管外径向速度波形与实验测定结果基本吻合,给出了从正常过滤过程到脉冲反吹结束的全过程中引射区域和滤管内速度场及温度场的变化, 分析了反吹气体温度对滤管内温度分布的影响.模拟结果表明,过滤器的操作温度与反吹气体温度差提高,会加剧滤管轴向方向脉冲清灰不均匀性.     

操作参数对陶瓷过滤管脉冲反吹清灰过程的影响

在由单根陶瓷过滤管组成的实验装置上,利用U形管压差计及压阻式压力传感器分别测定了过滤含粉煤灰气体时滤管内外压差和脉冲反吹时滤管内的瞬态压力. 结果表明,在进入连续稳定循环过程后,单根滤管在各个循环的清灰效率仍存在较大的波动.在过滤参数不变而仅改变反吹参数的情况下,可依据反吹压力波形正压峰值来判断清灰效率的优劣. 同时分析了重要操作参数对反吹压力波形及清灰效率的影响. 指出脉冲宽度对清灰效率几乎没有影响;在满足清灰要求的前提下,再提高反吹压力对清灰并没有明显的改善效果;而过高的过滤速度对清灰效率极为不利,会导致过滤循环操作无法正常进行.     

高温气体过滤除尘脉冲反吹再生过程的研究进展

叙述近年来高温气体过滤除尘技术的实验和理论研究进展,指出脉冲反吹再生过程是高温气体过滤除尘过程持续操作的关键。操作参数以及结构设计(包括喷嘴直径、喷嘴与文氏嘴之间的距离、喷嘴出口速度以及文氏嘴结构等)对除尘工艺过程和再生效果具有很大影响。分析了脉冲反吹过程中所涉及的传递现象数值模拟,以期更为深入地了解反吹再生过程的气流流动与能量传递规律,以指导和优化过滤装置的操作参数和结构设计。     

陶瓷滤管运行过程中的振动特性测定与分析

为分析实际生产中陶瓷滤管断裂的原因,利用电涡流位移传感器测定了陶瓷滤管在气体反吹时的振动,并测量了操作参数对陶瓷滤管振动的影响. 结果表明,陶瓷滤管在反吹时会产生径向位移,由于陶瓷滤管抗形变能力弱,可能会导致滤管发生断裂;另外,改变反吹压力对滤管振幅影响较大,反吹压力从0.3 MPa升至0.5 MPa时,滤管的振幅增加约40%;而改变过滤速度、脉冲宽度对滤管振幅影响较小,但会影响滤管振动的持续时间.     

核电站蒸汽发生器的鼓泡清洗

鼓泡清洗技术工艺简单,成本低廉,适用于核电站蒸汽发生器的预防性清洗和恢复性清洗。鼓泡清洗可以清洗包括支撑板缝隙在内的全管束。在现场常与泥渣枪清洗和化学清洗相结合操作。鼓泡清洗也适用于欠电站以及多种工业热交换器的清洗。     

Simulation of operational behaviour of patchily regenerated, rigid gas cleaning filter media

Particle removal from hot process gases is frequently accomplished with regenerable ceramic filters. When regenerating such media periodically, the dust cake may be detached from parts of the filter surface while other regions remain intact (‘patchy cleaning’). The filtration process depends on how these patterns of incomplete regeneration evolve over a number of cycles, how they change the build-up of the new cake, and how they affect the pressure drop. A two-dimensional quasi stationary flow model is used to predict pressure drops as a function of regeneration efficiencies and regeneration patterns, taking into account the finite thickness and flow resistance of the medium itself. The effect of non-uniform cake build-up on the pressure rise during a filter cycle is also modelled for a partially regenerated filter. The calculations prove that the pressure drop rises faster for lower regeneration efficiencies and that also cycle times become briefer with lower regeneration efficiency. It can also be shown, that the regeneration pattern only influences the pressure drop curve at the very beginning of the filtration cycle but does not influence the filtration cycle times.     

Numerical analysis of flow field in the hot gas filter vessel during the pulse cleaning process

The flow field is simulated for a ceramic filter vessel containing three candle filters which are arranged in the form of an equilateral triangle. Grids generated by GAMBIT are adopted for the simulations. The Reynolds stress model provided by FLUENT code is applied to evaluate gas flow and temperature field in the filter vessel. The temperature profiles in the ceramic candle filter cavity during the pulse cleaning process are analyzed under different operating conditions and for different lengths of candle filter. The evolution of radial velocity in the porous wall of the filters being cleaned and the normal working filters as well as around the filters is discussed. Sharp temperature change takes place in the top of the candle filter which is subject to thermal stress. The phenomenon of temperature increase during the pulse cleaning process has been carefully observed and interpreted based on the effect of gas compression. The simulated results show qualitative agreement with the experimental field observations with the filter vessel.     

熔体过滤器清洗工艺优化

阐述了通过增加一道高压水清洗、热水洗以及对泡点试验和过滤芯组装等过程的优化,达到节能降耗,提高清洗效率,延长了过滤器使用周期,消除了此工序给聚酯生产带来的安全隐患。     

高压水射流-机械联合清洗方法在换热器中的应用

介绍了高压水射流清洗方法和机械清洗方法的特点和清洗行业中的应用范围。通过高压水射流-机械联合方法在清洗换热器中的应用实例,阐述了联合清洗方法使用的必要性。     

Experimental study on the nozzle effect of the pulse cleaning for the ceramic filter candle

The effects of the nozzle size and its shape for the pulse cleaning of a ceramic filter candle were observed experimentally in the hot and cold bench units using commercial filter elements. The traces of the transient pressure, temperature, and overpressure in the filter cavity were measured to estimate the pulse cleaning effects. At the given pulse cleaning system, the pulse cleaning was optimized by the reciprocal effect of the nozzle size, which increases the primary pulse gas mass and reduces the secondary pulse mass as its size increases. The convergent nozzle showed a higher pulse effect than the straight one due to its concentrating effect, which leads to high pressure of the gas leaving the pulse nozzle.     

油管清洗用高压水射流技术

油田油管清洗是个很大的市场,以高压水射流清洗工艺取代传统的化学清洗工艺设计了油管内外壁同步清洗装置［１］．介绍了在此基础上开发的第二代油管清洗装置产品,其特点是实现了上管、清洗至下管全过程的手动与自动控制,安全可靠．装置同时适用２５″（６２ｃｍ）与３″（７６ｃｍ）油管的清洗,同时,对不同垢层的油管清洗速度无级可调,进一步提高了清洗效率．对油管外壁的清洗,开发了大直径（Ｄ２００ｍｍ）高压旋转喷头,是一项实用性很强的高压水射流技术．     

84消毒液除菌过滤后滤芯清洁方法的探讨

对84消毒液除菌过滤后的滤芯,进行3种不同的清洁方法的清洗,探讨最佳的清洁方法。方法对1号滤芯用70℃的注射用水冲洗20分钟,再用20℃的纯化水冲洗5分钟冷却;对2号滤芯用70℃的注射用水冲洗5分钟,再用95%的乙醇冲洗5分钟,然后用20℃的纯化水冲洗5分钟。对3号滤芯用70℃的注射用水冲洗5分钟,连接蠕动泵,用95%的乙醇冲洗5分钟,然后用70℃的注射用水冲洗5分钟,再用20℃的纯化水冲洗5分钟冷却,对1、2、3号清洁方法后滤芯分别进行完整性检测实验。通过1,2号的清洁方法,滤芯不能通过完整性检测实验,而通过3号的清洁方法的滤芯可以通过完整性检测实验。对1号方法未完成完整性检测实验的滤芯再用95%的乙醇冲洗5分钟,用70℃的注射用水对滤芯冲洗5分钟,再用20℃的纯化水冲洗5分钟冷却,其结果能通过完整性检测试验;对方法2,未完成完整性检测实验的滤芯再用70℃的注射用水对滤芯冲洗5分钟,再用20℃的纯化水冲洗5分钟冷却,其结果能通过完整性检测实验。经过验证,通过3号清洁方法对84消毒液除菌过滤后的滤芯进行的清洗是一种有效的清洁方法。     

高压设备不停产化学清洗技术的研究与应用

根据对高压设备操作工艺结垢情况的调查研究和作者的经验．将HX-5清洗剂成功地甩于不停车清洗高压设备，并介绍了北京篮星清洗公司和吐哈油田对HX-5的研制过程和应用实例。     

高压水射流清洗机能量分布及清洗效率分析

目前我国高压水射流清洗机使用数量达数千台,但由于用户对清洗机的能量分布和如何更好地利用能量不熟悉,造成了极大的浪费,能耗大、效率低,该清掉的垢物清洗不下来.针对这一普遍现象做一些理论分析,以让这些机器发挥最大效率,让用户获得最大经济效益.