Methods and apparatus for treating wastewater

Abstract

Apparatus for diluting and activating polymer molecules includes primary polymer dilution and activation apparatus, secondary dilution apparatus, and apparatus for diverting a desired amount of dilution water around the primary dilution and activation apparatus to the secondary dilution apparatus. The primary dilution and activation apparatus includes a cylindrical first processing zone in which the polymer and dilution water are initially mixed. The first processing zone subjects the polymer molecules to relatively high shear conditions for a relatively short period of time, after which the solution passes into a second cylindrical or annular processing zone in which the solution is subjected to continuously decreasing shear forces over a longer period of time. When the solution leaves the primary activation apparatus, it flows into the secondary activation apparatus, which is a static mixer. A valve diverts a desired amount of dilution water around the primary dilution and activation apparatus to the inlet of the secondary dilution apparatus. Water in the valve passes through a slot which extends through about 180 degrees. The ends of the slots have square corners, so that the total volume of water which passes through the valve and the relative proportion of water which passes through the primary and secondary activation apparatus can be adjusted independently of each other. In this manner, a control system can be used which only requires information regarding the total amount of water supplied to the system in order to execute operator instructions as to the total volume of water required and the proportions of water to be supplied to the primary and secondary dilution apparatus.

Dependencies are inferred from the claim text.