滤砖演进历史以及在工程应用中的优化
王敦宝
(达沃科环境(上海)有限公司,上海)
摘要 随着污水排放标准逐步提高,污水处理的难度也逐渐提升,对二级生物处理工艺稳定性的考验日渐加剧,导致很多水厂开始考虑增加三级处理工艺来提高出水的稳定性,而众多三级处理工艺中,各种滤池历经时间的考验占有一席之地。滤砖作为滤池的核心组件,相较于滤板滤头等其它种类的承托/布水布气装置,具有一系列天然优势。本文简要介绍了滤砖的演化历史,对比了不同时期滤砖结构设计的区别,总结了滤砖随着新材料的应用以及工程经验积累而产生的变化。本文可以为滤砖的选型和创新提供参考。
关键词 滤池;滤砖;盘式;S型;布水布气
Evolution History of Underdrain Blocks and Optimization in Engineering Applications
Wang, Dun bao
(Davco Environment (Shanghai) Co., Ltd, Shanghai)
Abstract With the gradual improvement of sewage discharge standards, the difficulty of sewage treatment has gradually increased, and the test of the stability of the secondary biological treatment process has become increasingly intensified. As a result, many water plants have begun to consider adding tertiary treatment processes to improve the stability of the effluent, and many tertiary treatment processes have become increasingly difficult. In the first-level treatment process, various filters have a place that has stood the test of time. As the core component of the filter, filter bricks have a series of natural advantages compared to other types of support/water and gas distribution devices such as filter plates and filter heads. This article briefly introduces the evolution history of filter bricks, compares the differences in structural design of filter bricks in different periods, and summarizes the changes in filter bricks with the application of new materials and the accumulation of engineering experience. This article can provide reference for the selection and innovation of filter bricks.
Keywords filter, underdrain block, disc type, S-type, water and gas distribution.
1. 背景
伴随第二次工业革命的到来,各行各业飞速发展,与此同时产生的水污染问题逐渐被人们所重视。20世纪中叶开始,反硝化滤池作为脱氮反应器从美国兴起,因其具有经济性、稳定性、高效率的特点广受推崇。时至今日,在技术革新的推动下产品也完成了一次次的迭代。从系统设计到硬件设计,每一环都深刻影响着滤池的好与坏。今天给大家介绍的是反硝化深床滤池系统核心模块之一:滤砖。
2. 内充混凝土滤砖的演变
以滤池结构为例分析,滤砖铺设于池底,其上方为承托层及滤料层,这对滤砖的承重性能提出了较高的要求。早期滤砖以混凝土浇筑或烧制为主,制作时对误差的控制有限,因此良品率较低;运输过程中发生磕碰等也会影响交付,以至于要保有备件从而增加成本。20世纪90年代滤砖被套上外壳,虽然滤砖之间没有互锁稳定装置,但其薄壳结构仍起到承重与围护作用。后来的改良滤砖在长边侧加上互锁卡扣并沿用至今。