System and method for determining a deposition rate in a process stream indicative of a mass build-up and for controlling feed of a product in the process stream to combat same

A system for measuring anti-scalant efficacy or biocide or non-toxic dispersant on-line, in a process stream, the system comprising:

• a first sensing means detecting frequency change in the process stream and producing a signal indicative thereof;
• processing means receiving a signal from the first sensing means and producing a feed signal;
• feeding means responsive to the feed signal and capable of feeding a product into the process stream as a result of the feed signal;
• and
• a second sensing means capable of detecting frequency change in the process stream after feeding the product into the processing means and producing a signal indicative thereof wherein the processing means is capable of receiving the signal from the second sensing means to compare with the signal from the first sensing means to provide an indication of the efficacy of the product in the process stream.

A method for controlling product feed into a process stream, the method comprising the steps of:

• monitoring scale deposition or biofilm build-up on a first probe placed in the process stream and producing a first signal indicative thereof;
• feeding a product into the process stream;
• monitoring scale deposition on a second probe placed in the process stream after the product is fed in the process stream and producing a second signal indicative thereof;
• determining efficacy of the product in the process stream by comparing the first signal with the second signal;
• and
• controlling feed of product based on the determined efficacy.