Variable residence time treatment system

A variable residence time treatment system for receiving, treating and discharging a variable flow of liquid, comprising, in combination:

• a) containment means having a variable effective holding volume for treatment of a liquid and comprising
• inlet means for admitting the liquid and a treatment material to adjust a measurable property of the liquid,
• mixing means for mixing said liquid with said treatment material within the containment means, and
• discharge means for passing a discharge flow of treated liquid from the containment means, wherein the discharge means comprises a discharge outlet open full-time during operation of the system to pass, as needed, a portion of the discharge flow of treated liquid from the containment means at its full holding volume, and variable residence time means for controlling the effective holding volume of the containment means in response to a holding volume control signal by selectively passing a portion of the discharge flow of treated liquid from the containment means at less than its full holding volume;
• b) sensor means for monitoring a measurable property of the liquid and for generating a corresponding first signal, comprising an inlet pH sensor for monitoring the pH of liquid entering the containment means and an inlet flow sensor for measuring the volume of liquid entering the containment means;
• and
• c) control means operatively connected to the sensor means, and to the variable residence time means for generating the holding volume control signal in response to the first signal;
• and
• d) containment sensor means for monitoring the pH of liquid being treated within the containment means and for generating a corresponding containment pH signal to the control means, containment level sensor means for measuring the amount of liquid being treated within the containment means and for generating a corresponding containment level signal to the control means, discharge pH sensor means for continuously measuring the pH of treated liquid discharged from the treatment system and for generating a corresponding discharge pH signal to the control means, and discharge flow sensor means for measuring a volume of discharge flow from the treatment system and for generating a corresponding discharge flow signal to the control means, and wherein the holding volume control signal is generated by the control means at least in part in response to said first signal, said containment level signal said discharge pH and signal and said discharge flow signal.

A variable residence time treatment system for receiving, treating and discharging a variable flow of liquid, comprising, in combination:

• a) containment means having a variable effective holding volume for treatment of a liquid and comprising
• inlet means for admitting the liquid and a treatment material to adjust a measurable property of the liquid,
• mixing means for mixing said liquid with said treatment material within the containment means, and
• discharge means for passing a discharge flow of treated liquid from the containment means, wherein the discharge means comprises a discharge outlet open full-time during operation of the system to pass, as needed, a portion of the discharge flow a portion of from the containment means at its full holding volume, and variable residence time means for controlling the effective holding volume of the containment means in response to a holding volume control signal by selectively passing the discharge flow of treated liquid from the containment means at less than its full holding volume;
• b) sensor means for monitoring a measurable property of the liquid and for generating a corresponding first signal;
• c) control means operatively connected to the sensor means, and to the variable residence time means for generating the holding volume control signal in response to the first signal;
• d) a baffle module for receiving the discharge flow;
• and
• e) recirculation means for passing treated liquid from the baffle module back into the containment means.

A variable residence time treatment system for receiving, treating and discharging a variable flow of aqueous waste effluent, comprising, in combination:

• a) containment means having a variable effective holding volume for treatment of an aqueous waste effluent and comprising
• inlet means for admitting the aqueous waste effluent and a treatment material to adjust a measurable property of the aqueous waste effluent,
• mixing means for mixing said effluent and said treatment material within the containment means, and
• discharge means for passing a discharge flow of treated aqueous waste effluent from the containment means, wherein the discharge means comprises a discharge outlet open full-time during operation of the system to pass, as needed, a portion of the discharge flow to treated effluent from the containment means at its full holding volume, and variable residence time means for controlling the effective holding volume of the containment means in response to a holding volume control signal by selectively passing a portion of the discharge flow of treated effluent from the containment means at less than its full holding volume;
• b) sensor means for monitoring a measurable property of the effluent and for generating a corresponding first signal;
• and
• c) control means operatively connected to the sensor means, and to the variable residence time means for generating the holding volume control signal in response to the first signal.