• 2021年8月10日
    vch11602707
      导  读     在污水处理过程中,总会遇到各种各样的污水问题,比如:COD、氨氮、TP等指标不达标,污泥膨胀、浮泥、活性微生物死亡等,当我们遇上这些问题的时候,不妨拿出这篇文章进行对照解决问题。     一、出水水质   1、有机物   影响有机物处理效果的因素主要有:   (1)营养物 一般污水中的氮磷等营养元素都能够满足微生物需要,且过剩很多。但工业废水所占比例较大时,应注意核算碳、氮、磷的比例是否满足100:5:1。如果污水中缺氮,通常可投加铵盐。如果污水中缺磷,通常可投加磷酸或磷酸盐。   (2)pH 污水的pH值是呈中性,一般为6.5~7.5。pH值的微小降低可能是由于污水输送管道中的厌氧发酵。雨季时较大的pH降低往往是城市酸雨造成的,这种情况在合流制系统中尤为突出。pH的突然大幅度变化,不论是升高还是降低,通常都是由工业废水的大量排入造成的。调节污水pH值,通常是投加氢氧化钠或硫酸,但这将大大增加污水处理成本。   (3)油脂 当污水中油类物质含量较高时,会使曝气设备的曝...
  • 2021年8月9日
    vch11602707
    1、为什么需要预过滤器? 除病毒过滤在生物制药的过程中是一个关键步骤。然而即使是层析纯化后的样品,蛋白聚体和杂质也会限制除病毒过滤器的载量,导致过滤膜面积增加。 除病毒滤器堵塞主要是基于以下原因: 除病毒膜孔需要透过蛋白拦截病毒,对膜孔径要求较高。 细小病毒直径约为18-24nm,单抗分子约为8-12nm。聚体将导致膜孔堵塞。 随着蛋白浓度提高,蛋白单体产生聚体的几率变大,增加了堵塞除病毒滤器的风险。 蛋白不稳定导致结构改变或碎片,以及其他未分离杂质,也有可能导致堵塞。 对样品进行预过滤处理能够有效的去除这些堵膜因素,因此许多工艺会加入预过滤器来提高除病毒过滤器的载量从而降低工艺成本。通过研究和大量实践表明,增加预过滤器后的除病毒滤器的平均载量能比未增加提高2倍以上。 2、如何选择预过滤器 预滤器的选择需要根据样品特性和工艺需求来决定。一般对于去除单抗工艺中的聚体来说,吸附比基于分子大小的尺寸排阻的预过滤方式更有效。 默克提供了表面改性膜和吸附型深层滤器这两种预过滤器,针对于不同的需求,达成稳健的工艺目的。 Vire...
  • 2021年8月6日
    vch11602707
    Recently, local cases have been confirmed in many places. As of 24:00 on August 3, 2021, 31 provinces (autonomous regions, municipalities directly under the Central Government) and the Xinjiang Production and Construction Corps reported 71 new local confirmed cases and 15 new asymptomatic infections.The General Office of the National Health Commission released the Technical Guidelines for the Prevention and Control of Novel Coronavirus Infection (Second Edition). What guiding significance does it have for the current normalized epidemic prevention and control? Lan Guaping, the infection control plus operation team, brought "A look at the current normalized prevention and control of the epidemic from the second edition of prevention and control guidelines."...
  • 2021年8月5日
    vch11602707
    Viral filtration is a common step in the production of many biologics, and viral contaminants of different particle sizes can be removed depending on the pore size of the filter. Integrity Testing (IT) is a way to confirm the retention capacity of a filter. Integrity testing before use can confirm whether the filter has been damaged during transportation and whether the filtration system is set up correctly. Post-use testing can confirm the integrity of the membrane cassette to confirm the effectiveness of the virus removal process. This article supplements the Viresolve® Pro Solution User Guide and is designed to minimize the risk of integrity test failure. Describes the key influencing factors of using automated integrity testers, troubleshooting methods and corresponding measures after test failure. The pre-filters Viresolve® Pro Shield and Viresolve® P...
  • 2021年8月4日
    vch11602707
    The popularity of paper bags is not the result of environmental protectionFriends, the "plastic restriction order" has been implemented in China for 12 years. Are you surprised? After 12 years of hard work, plastic bags are no longer flying blatantly on the streets.The author believes that everyone has a common understanding: plastic bags pollute the environment, and most people think that using paper bags is to protect the environment. For breakfast, people subconsciously feel that paper bags are more environmentally friendly than plastic bags. So are paper bags really as environmentally friendly as people think? Beautified paper bag Paper bags are considered environmentally friendly because of their reputation for being highly recyclable and easy to decompose. But if we look at the life cycle of paper bags, you will find that it is not that beautiful.Life cycle: the entire ...
  • 2021年8月4日
    vch11602707
    简介 水处理厂在为消费者生产安全饮用水的过程中,需要监测多种水质参数,包括水中的pH值、总有机碳TOC、UV 254吸光度。TOC和UV 254吸光度是评估水中有机物(OM,Organic Matter)含量和质量的重要参数。   TOC和紫外吸光度都取决于水中的有机物。正确了解两者的关系,就能避免错误解读水质监测数据。本文讨论了这两个参数间的关系,以及它们在水处理工艺和合规性方面的应用。文中使用的Sievers® M5310 C分析仪为TOC分析提供了最佳解决方案,实际样品数据也证明了此款分析仪的实用性。   技术比较 有机物  有机物是指水中的各种化合物的混合,包括自然物质(即植物、动物、微生物)降解后产生的天然有机物(NOM,Natural Organic Matter),以及生活污水带来的有机物1。尽管有机物本身对人体健康无害,但它会与氯反应产生消毒副产物(DBP,Disinfection Byproducts)。消毒副产物对人体健康有害,因此法规要求水处理厂在处理水时控制有机物的浓度2,3。   TOC和紫外吸光度在有机物分析中的应用 TO...