US 6,549,817 B1 · Method for regulating centrifuges for dehydrating wastewater sludge, using fuzzy logic

Abstract

A process for regulating a centrifuge used for solid/liquid separation of sewage sludge commences by measuring the input variables of the operating point ot the centrifuge, the variables including 1) suspended matter content of the centrate; 2) the flow rate of sludge; 3) the flow rate of reagent; and 4) the value of torque of the motor of a conventional centrifuge. Operating zones are established, each of which is two dimensional relative to the input variables. Fuzzy logic rules are established, qualifying the operation of the centrifuge, the rules respectively corresponding to the zones. The rules are implemented in response to the input variable measurements, where actions on the sludge flow rate and reagent flow rate make it possible to bring the operating point into a particular zone of optimal and stable centrifuge operation.

Claims5

Dependent claims

A process for regulating a centrifuge used for solid/liquid separation of sewage sludge, the process comprising the steps:

measuring the input variables of the operating point of the centrifuge, the variables including;
a) suspended matter content of the centrate;
b) the flow rate of sludge;
c) the flow rate of reagent;
d) the value of torque of the motor of a conventional centrifuge;
establishing operating zones, each of which is two dimensional relative to the input variables;
establishing fuzzy logic rules qualifying the operation of the centrifuge, the rules respectively corresponding to the zones;
implementing rules, in response to the input variable measurements, where actions on the sludge flow rate and reagent flow rate make it possible to bring the operating point into a particular zone of optimal and stable centrifuge operation.

5 more elements

A device for regulating a centrifuge used for solid/liquid separation of sewage sludge, the device comprising:

means for measuring suspended matter content of the centrate;
means for measuring the flow rate of sludge;
means for measuring the flow rate of reagent;
means, selectively employed, for measuring the value of torque of a motor of a conventional centrifuge;
means, selectively employed, for measuring the relative speed of an intensive centrifuge screw with respect to a centrifuge bowl;
means for implementing fuzzy logic rules that gauge the operation of the centrifuge, the rules corresponding to operational zones, each of the zones being two dimensional relative to input variables for which all the measuring means are provided;
wherein a particular zone represents a stable and optimal operating zone corresponding to a particular rule according to which the sludge flow and reagent rates remain unchanged so long as a point of centrifuge operation lies in the particular zone;
means for periodically determining, by fuzzy logic, on the basis of the rules, other that the rule corresponding to the particular zone new targets for the sludge flow rate and the reagent flow rate, bringing the point representative of the operation of the centrifuge into the particular zone.

5 more elements

Dependencies are inferred from the claim text.

Method for regulating centrifuges for dehydrating wastewater sludge, using fuzzy logic

Life of this patent

Method for regulating centrifuges for dehydrating wastewater sludge, using fuzzy logic

Life of this patent

Abstract

Claims5