초록 ▼

The operation of a continuous thickener, clarifier, or similar device having a feed well into which a feed slurry of suspended solids and a flocculant are continually introduced to effect separation of the slurry into a clarified solution which is withdrawn through an overflow launder and a thickene

The operation of a continuous thickener, clarifier, or similar device having a feed well into which a feed slurry of suspended solids and a flocculant are continually introduced to effect separation of the slurry into a clarified solution which is withdrawn through an overflow launder and a thickened sludge which is transported into a discharge port at the bottom of the unit is controlled by establishing the slime level at a point near the bottom of the feed well, continuously monitoring the density of the downflowing slurry within the well, and regulating the rate of flocculant addition in response to small changes in the slurry density.

대표청구항 ▼

A method for controlling the operation of a continuous gravity sedimentation unit having a feed well into which a slurry of suspended solids and a flocculating agent are introduced to effect separation of said slurry into a clarified solution that is recovered from said unit as an overflow liquid an

A method for controlling the operation of a continuous gravity sedimentation unit having a feed well into which a slurry of suspended solids and a flocculating agent are introduced to effect separation of said slurry into a clarified solution that is recovered from said unit as an overflow liquid and a sludge that is withdrawn from the bottom of said unit whereby consumption of flocculating agent is reduced comprising the steps of establishing a slime level within a predetermined optimum distance from the bottom of said feed well by varying the flow rates to and from said unit, detecting changes in the density of the downflowing slurry over a vertical interval in said feed well, correlating said density changes in the solids settling rate within said well, and continuously varying the rate at which said flocculating agent is introduced into said feed well in response to said changes in density and whereby control of both settling rate and slime level is obtained.