慢速砂滤在欧洲得到广泛应用，在美国作为处理优质地表水的一种手段再次引起人们的兴趣。然而，人们担心缓慢砂滤去除有机前体材料的能力有限。尽管过滤速率低，空床接触时间长，但传统的慢速砂滤器对有机渗透物质的去除有限，具有较高的过滤效率。（DOC）和三卤甲烷形成的潜在减少量平均低于15-25%。通过缓慢砂滤提高有机物去除率的两种改进措施是颗粒介质修正和预分区。本研究的目的是评估使用颗粒介质改良剂（如阴离子交换树脂、颗粒活性炭（GAC）、氧化铝、斜发沸石和无烟煤）缓慢砂滤对THM前体去除的改善。结果表明，在89天的过滤器运行期间，使用阴离子树脂和颗粒活性炭（GAC）改良的过滤器对有机碳和三卤甲烷的去除率显著高于所研究的任何其他过滤介质组合。 包括28个参考文献、表格和图表。

Slow sand filtration is widely used in Europe and is enjoying renewed interest in the United States as a means of treating surface water of good quality. There are concerns, however, about the limited ability of slow sand filtration to remove organic precursor materials. Despite low filtration rates and long empty-bed contact times conventional slow sand filters have achieved limited removals of organic percursor material, with. (DOC) and trihalomethane formation potential reductions averaging less than 15-25 percent. Two modifications that have been explored for improving organic removals by slow sand filtration are granular media amendments and preozonation. The objective of this research was to evaluate slow sand filtration improvements in THM precursor removals using granular media amendments such as anionic exchange resin, granular activated carbon (GAC), aluminum oxide, clinoptilolite and anthracite. Results showed that filters amended with anionic resin and granular activated carbon (GAC) achieved significantly higher (>75 percent) removals of organic carbon and trihalomethane formation potential during an 89 day filter run than any other filter media combination studied. Includes 28 references, tables, figures.