粗石英砂滤料上向流过滤机理与应用研究

【作者】 郭梅修；

【导师】 吴光春； 曾光明；

【作者基本信息】 湖南大学 ， 环境工程， 2002， 硕士

【摘要】 过滤是水处理流程中的关键环节。世界上不少水处理专家认为“反粒度过滤”能克服传统“下向流过滤”的缺点，会取得高效优质的过滤效果。本文对粗石英砂滤料上向流过滤技术进行了理论和实验研究，在单一的滤层中待滤水循粒径最粗的底层进，从粒径最细的表层出，攻克了“反粒度过滤”的关键技术。中试研究结果表明，粗石英砂滤料上向流过滤比传统的重力流过滤具有更大的含污能力和产水量，为适用较高的反冲洗强度(21L／(m~2·s))以便滤料清洗更干净，采用粒径范围为0.63～2.00mm的粗石英砂滤料，滤层厚82～85cm，水温6～27℃，进水浊度为30NTU左右等情况下，能获得平均滤速为16～18m／h、平均滤后水浊度为1NTU左右、周期达14～24小时的好效果。生产规模的运行实验显示粗石英砂滤料上向流过滤对悬浮颗粒的去除是有效的，反冲洗干净彻底，过滤周期长，当平均滤速为20m／h时，出水浊度为1NTU。按该技术成功运用的典型柳东水厂的设计参数，反粒度滤池较一般快滤池滤速可提高50％以上，因此，其面积比同规模的其他滤池至少减少1／3，从而节省了大量的基建投资，经营费亦有减少，特别适用于水厂滤池挖潜改造，这是一种有潜力的过滤技术，尤其适用于对滤池进行改造以提高其产水量这样的情况。更多还原

【Abstract】 Filtration is the key step of a water-treatment process. Some specialists in the world put forward the theory of reverse grain filtration what would be of high filtration efficiency and good water quality comparing to Down-flow filtration. Up-flow filtration with coarse sand media, the water intaking from the bottom layer where the particle diameters of coarse media were the widest and outputting from the surface layer where the particle diameters of coarse media were the thinnest in the single media, was studied theoretically and experimentally in this research. It solved the difficult technical problem of reverse grain filtration. Pilot-scale experimental results showed that, comparing to conventional gravity filtration, the up-flow filtration has greater capacity in containing removed suspended solid and producing filtrate under the test conditions. Coarse media with particle diameter ranging 0.63-2.00mm were used in order to apply relatively higher backwash rate of 21 L/(m2 .s) for achieving better media clean-up after a filtration run. Under the test conditions, the media thickness ranging 82-85 iron, water temperature ranging 6-27, and influx turbidity of 30 NTU, it achieved the results of the average filtration rate ranging 16-18 m/h, the average effluent turbidity of 1 NTU, and action cycle ranging 14-24h. Further, full-scale experiments were carried out and the results demonstrated that the up-flow filtration with coarse media was efficient in removal of suspended solid, backwash of cleaning, and long action cycle. An effluent turbidity of 1 NTU was always achieved with an average filtration rate of 20 m/h. The design parameters of Liudong waterworks showed that, the rate of the Up-flow filtration improved over 50% comparing to the normal Down-flow filtration. So its filter area is less one-third than the others in same scale for less investment. It is a promise filtration technology especially suitable for the cases of filter renovation in order to increase its filtrate.更多还原