一款用于无线通信系统的小型滤波器天线

目的设计一款适用于现代无线通信系统小型的滤波器天线。方法由一微带开口环谐振器、一段耦合线和一个Г型天线组成一款滤波器天线。这个Г型天线由耦合线激励,在设计中起着导纳变换器的作用。Г型天线不仅起着辐射的作用,同时也是滤波器最后一个谐振器,使滤波器和天线之间基本没有损耗,在仿真调试后,加工成实物进行测试。结果该滤波器天线在反射系数S11<-10 dB的阻抗带宽有12.7%(2.36~2.68 GHz),滤波器天线具有平坦的通带,通带内的最大差异为0.84 dB。滤波器天线通带外增益不到-15 dBi,这说明滤波器天线具有很好的带外抑制性。结论设计的滤波器天线通带内天线增益较为平坦,且拥有良好的带外抑制特性、滤波与辐射特性,并且损耗很低,很适合用于现代无线通信系统的射频前端。     

半干法脱硫配套布袋除尘器的特殊要求

由于半干法脱硫工艺对布袋除尘器的特殊要求,使得其配套的布袋除尘器构造不同于以往常规的布袋除尘器.从布袋除尘器的过滤风速、滤料选择、沉降室设置、布风均匀性、灰斗特性、旁路系统的要求做详细的说明.     

电袋复合除尘技术在燃煤电厂中的应用

电袋复合式除尘技术综合了电除尘和布袋除尘的收尘优点,通过除尘负荷的合理分配,实现了电除尘和布袋除尘的有机结合;采用基于表面过滤原理的新型滤料,可克服常规滤料清灰后除尘效率降低及滤袋易破损等缺点。电袋复合式除尘器在徐州坝山环保热电有限公司的应用实践表明,电袋复合式除尘器可保持高效稳定除尘同时节能,粉尘排放浓度达到了30 ...     

内循环(IC)反应器运行规律研究

研究采用自制内循环(IC)反应器,以实验室模拟废水为进水,接种城市污水处理厂的剩余污泥,对反应器的启动及运行过程进行研究,在经过污泥驯化、颗粒培养、调整及稳定的不同阶段连续运行.结果表明:启动初期反应器pH过低,产甲烷菌生长受抑制,导致VFA累积,容易酸化.通过改变模拟废水中微量元素的浓度及添加缓冲溶液,酸化的反应器可...     

免烧粉煤灰陶粒作为BAF填料处理城市污水

以电厂粉煤灰为主要试验原料,辅以外加药剂(水泥、石灰、石膏、水玻璃),经混合、成球、陈化和养护等工序,制得免烧粉煤灰陶粒,并将其作为曝气生物滤池(BAF)工艺的载体填料处理城市污水.待挂膜启动成功后,考察了水力停留时间( HRT)、COD负荷、氨氮负荷对COD和氨氮去除效果的影响.实验结果表明:在温度为18～21℃、气...     

Experimental study on filtration and continuous regeneration of a particulate filter system for heavy-duty diesel engines

This study investigated the filtration and continuous regeneration of a particulate filter system on an engine test bench, consisting of a diesel oxidation catalyst（DOC） and a catalyzed diesel particulate filter（CDPF）. Both the DOC and the CDPF led to a high conversion of NO to NO2 for continuous regeneration. The filtration efficiency on solid particle number（SPN） was close to100%. The post-CDPF particles were mainly in accumulation mode. The downstream SPN was sensitively influenced by the variation of the soot loading. This phenomenon provides a method for determining the balance point temperature by measuring the trend of SPN concentration.     

Aerobic granules cultivated and operated in continuous-flow bioreactor under particle-size selective pressure

A novel method based on the selective pressure of particle size （particle-size cultivation method, PSCM） was developed for the cultivation and operation of aerobic granular sludge in a continuous-flow reactor, and compared with the conventional method based on the selective pressure of settling velocity （settling-velocity cultivation method, SVCM）. Results indicated that aerobic granules could be cultivated in continuous operation mode by this developed method within 14 days. Although in the granulation process, under particle-size selective pressure, mixed liquor suspended solids （MLSS） in the reactor fluctuated greatly and filamentous bacteria dominated the sludge system during the initial operation days, no obvious difference in profile was found between the aerobic granules cultivated by PSCM and SVCM. Moreover, aerobic granules cultivated by PSCM presented larger diameter, lower water content and higher specific rates of nitrification, denitrifieation and phosphorus removal, but lower settling velocity. Under long term operation of more than 30 days, aerobic granules in the continuous-flow reactor could remain stable and obtain good chemical oxygen demand （COD）, NH4^＋-N, total nitrogen （TN） and total phosphorus （TP） removal. The results indicate that PSCM was dependent on the cultivation and maintenance of the stability of aerobic granules in continuous-flow bioreactors.     

SFBR中好氧颗粒污泥的培养及特性研究

接种自行培养的活性污泥,以模拟废水为基质,采用连续进水、间歇出水及厌氧/好氧交替的运行模式,尝试了在SFBR中进行好氧颗粒污泥的培养,并研究了好氧颗粒污泥的特性及反应器对污染物的去除效果.结果表明,通过逐步缩短沉降时间,28 d时成功培养出好氧颗粒污泥,所形成的好氧颗粒污泥呈黄色、形状不规则,且粒径较小(平均粒径0.56 mm),正常情况下的SVI保持在70 mL·g-1以下,EPS在59 d时达到最大值(以MLVSS计)373.24 mg·g-1,较培养初期增加了约2.5倍,运行后期由于颗粒出现解体,导致EPS急剧下降;反应器在运行过程中未能保持较高的污泥量,中后期MLSS始终在3 000mg·L-1以下;在63 d的运行时间里,除异常波动外,反应器对COD的去除率基本维持在90%左右,正常情况下出水COD小于100 mg·L-1,反应器对NH+4-N、TIN的去除效果波动较大,去除率分别为44.45%~94.72%及43.87%~93.13%,反应器对TP的去除率在44.50%~97.40%之间,正常情况下TP去除率可维持在60%以上;限于自动控制水平,夜间长时间的好氧饥饿期容易造成丝状菌过度生长,使得AGS在生长竞争中处于劣势,最终导致了AGS的解体.     

鞍钢钢绳厂生产污水处理的工艺设计及运行效果

本文介绍了鞍钢钢绳厂生产废水处理工艺,包括沉淀系统、气浮系统、砂滤罐过滤系统。通过试验确定p H为11时,沉淀系统对Zn2+的去除率达到98.4%。通过正交试验确定当PAC用量为20 mg/L、PAM用量为2 mg/L、p H 7.5、气浮压力为1.2 Mpa时气浮系统对钢绳厂废水中SS、石油类、COD的去除率分别达到90%、70%、70%。经过砂滤罐过滤系统后废水中的SS为20 mg/L、石油类为2 mg/L、COD为48 mg/L,其去除率分别达到94%、78%、80%。     

连续流反应器短程硝化的快速启动与维持机制

如何快速稳定地启动短程硝化工艺对低C/N比废水的处理具有十分重要的实际应用价值.针对城市污水厂以连续流工艺为主的现状,故对连续流反应器短程硝化的快速启动与维持进行研究.结果表明,利用间歇曝气,依次控制3个阶段的停/曝时间(15 min/45 min、45 min/45 min和30 min/30 min),连续流反应器经过60 d左右的运行,可以成功实现短程硝化的快速启动.控制停/曝时间为30 min/30 min,进水氨氮浓度为50或100 mg·L~(-1)时,亚硝化率分别可达90%或95%.另外,间歇曝气有利于抑制硝化菌(NOB)的活性,而缩短水力停留时间(HRT)可淘洗出NOB,两者结合可以更好地维持短程硝化.