Patent ID: 11866356
Assignee: KEMIRA OYJ
Field: Chemical engineering (Chemistry)
Classification: CPC C  B | IPC B  C

Claim 0:
1. A method of controlling a water treatment process, the method comprising:
adding at least one pretreatment chemical to a water stream in a pretreatment process including a coagulation step and/or a flocculation step and at least one separation step to reduce amount of dissolved and/or particulate matter in the water stream, wherein said at least one separation step contains a flotation step or a sedimentation step,
monitoring, in an online monitoring unit, hydrophobic conditions in the water stream upstream and/or downstream from said adding the at least one pretreatment chemical, wherein monitored and targeted hydrophobic conditions in the water stream are determined by determining hydrophobicity based on a fluorescence measurement, and by determining the amount or count of particles based on a light scattering measurement,
wherein dosing of said at least one pretreatment chemical to the water stream is based on the monitored hydrophobic conditions such that the hydrophobic conditions in the pretreated water are brought towards target hydrophobic conditions,
wherein a process controller of the pretreatment process is connected to a membrane cleaning system of a membrane filtration stage following the pretreatment process, and wherein the membrane cleaning system is controlled based on the monitored hydrophobic conditions.