Experimental study on the adoption of flushing technique in successive alkalinity-producing systems with a focus on influence radius of orifice

As a successive alkalinity-producing system pond for purifying mine drainage is operated, sediment accumulates in the limestone layer of pond, and as amount accumulated increases, water permeability treatment efficiency decrease. Hence, flushing required, comprising network perforated pipes installed layers, to periodically discharge outside. The performance depends on four distinct characteristics system: layer, sediment, flow, device. However, existing studies have evaluated entire without considering these conditions. In this study, new experimental method designing proposed. This based an experiment evaluate influence radius orifice, which spherical volume around orifice that can suck sludge by flushing. results showed flow rate through glass bead matched well with Blake–Kozeny formula, greater diameter is, orifice. according spacing was evaluated, provides key criterion system.