摘要 |
<p>In an extended aeration wastewater treatment system having wastewater flowing into a retention basin so as to form mixed liquor within the retention basin, a mixed liquor wasting system is provided, comprising a thickener tank, having a sidewall and a bottom; a waste line having a first end and a second end, the first end fluidly connected to the retention basin, and the second end fluidly connected to the thickener tank; a first flow control device, such as a pump, for continuously removing a portion of the mixed liquor from the basin at a desired constant flow rate through the waste line, positioned in the waste line; a sludge removal line having a first end and a second end, the first end fluidly connected to the bottom of the thickener tank, and the second end fluidly connected to a sludge disposal system; a second flow control device, such as a pump, for removing a concentrated portion of the mixed liquor from the thickener tank, positioned in the sludge removal line; and a return line having a first end and a second end, the first end fluidly connected to the thickener tank above the bottom, and the second end fluidly connected to the retention basin. A method for wasting mixed liquor is provided, comprising the step of continuously removing a portion of the mixed liquor from the basin at a desired constant flow rate.</p> |