Harmful pollution in river systems can be divided into point and non-point sources. According to a 2004 Ministry of the Environment survey non-point source accounted for 22% to 37% of pollution based on BOD. Water quality projections show non-point so...
Harmful pollution in river systems can be divided into point and non-point sources. According to a 2004 Ministry of the Environment survey non-point source accounted for 22% to 37% of pollution based on BOD. Water quality projections show non-point sources will account for 70-75% of pollution in 2015. Non-point pollution management is needed urgently.
In this study, non-point pollution from industrial complex storm drain runoff was processed by a Hydrodynamic filter separator (HDFS) that could automatically backwash the filter and separator. Perlite and EPP filters were tested with and without coagulants injection.
Experimental results using perlite filter media are SS 87%, BOD 60%, COD 79%, TN 36%, TP 67%. The same filter media with coagulants (0.1% PACS) increased efficiency 0~10 percent after injection relative to the flow of 1L/min ~ 5L/min. In addition, EPP filter media results of SS 69%, BOD 37%, COD 54%, TN 26%, TP 31% removal efficiency can be confirmed, but, very short duration of treatment was confirmed. Backwash experiments showed approximately 50% washing efficiency. When implementing HDFS equipment in the field, perlite filter media provides excellent benefits. When using perlite filters it is beneficial to
drain or partially drain in the bottom. In addition, injecting coagulants increases efficiency. However, maintenance demands must be considered when choosing whether to use coagulants or not. Backwash efficiency of approximately 50% was confirmed when draining from the
bottom of the equipment. Without bottom drainage, filter media requires replacement or external cleaning. Therefore, these extra cleaning methods should be considered when used in the field.