Compositions and methods for microbiological control in a paper machine coating kitchen

A method of monitoring and controlling microbiological activity in a coating slurry and/or a component thereof, comprising:

• (a) providing a monitoring and controlling unit comprising a controller and a plurality of sensors in communication with the controller, wherein the plurality of sensors includes a pH sensor operable to measure a pH of the coating slurry and/or the component thereof and an ORP sensor operable to measure an ORP of the coating slurry and/or the component thereof;
• (b) entering an acceptable range for the pH of the coating slurry and/or the component thereof and the ORP of the coating slurry and/or the component thereof into the controller;
• (c) adding a stabilizer, a chlorine source, and water to a reactor;
• (d) mixing the stabilizer, the chlorine source, and the water in the reactor;
• (e) forming a stabilized chlorine composition in the reactor;
• (f) adding the stabilized chlorine composition to the coating slurry and/or the component thereof via a delivery conduit;
• (g) transporting a portion of the coating slurry and/or the component thereof via a side stream conduit to an inlet of the monitoring and controlling unit;
• (h) measuring the pH and the ORP of the coating slurry and/or the component thereof with the pH sensor and the ORP sensor, respectively;
• (i) determining if the measured pH is within the acceptable range entered into the controller in step (b);
• (j) determining if the measured ORP is within the acceptable range entered into the controller in step (b);
• (k) carrying out a corrective action if the measured pH and/or ORP is outside of the acceptable range entered into the controller in step (b);
• and
• (l) optionally repeating one or more of steps (a) to (k) to determine if the pH and/or ORP of the coating slurry and/or the component thereof has been brought within the acceptable range entered in step (b).

A method for controlling microbiological activity in a coating slurry and/or a component thereof, comprising:

• measuring a first pH of the coating slurry and/or the component thereof with a pH sensor and/or measuring a first oxidation-reduction potential (ORP) of the coating slurry and/or the component thereof with an ORP sensor;
• adding a stabilizer and a chlorine source to the coating slurry;
• mixing the stabilizer and the chlorine source in the slurry to form a stabilized chlorine composition;
• and
• adding additional stabilizer, chlorine source, and/or stabilized chlorine to the coating slurry and/or the component thereof if the measured first pH and/or first ORP decreases.