| 摘要 |
<p>A system for distributing both gas and liquid in separate conduits within an underdrain filtration system is disclosed. A tubular liquid conducting conduit (100) also contains a separate air conduit (130). Extending from each conduit are, respectively, liquid conducting laterals (112, 114) and air laterals. The system is placed within a bed of gravel at the bottom of a filter bed and acts as conventional underdrain blocks and air grids. The disclosed system requires a height within the filter that is about equal to the height of the liquid conduit (100), thus, maximizes filter media depth and permits retrofit applications into relatively shallow filter beds. Methods of installing an underdrain in a filtration system are also disclosed.</p> |
