Method and Apparatus for Acoustically Detecting Fluid Leaks

A fluid leak detection system for an industrial furnace installation including an industrial furnace, the fluid leak detection system including:

• a cooling circuit for positioning in thermal communication with at least part of the industrial furnace, the cooling circuit including a fluid conduit for receiving a substantially free-surfaceless flow of cooling fluid therealong;
• an acoustic emitter positioned at a first location along said conduit;
• and
• an acoustic sensor positioned at a second location along said conduit spaced from said first position,
• a processor electronically communicating with the acoustic sensor and operable to output control signals to control at least one operating parameter of the industrial furnace installation,
• the acoustic emitter operable to output and propagate at least one output acoustic signal through said flow of cooling fluid, the at least one output acoustic signal including at least one preselected frequency component having a frequency range selected to preferentially propagate along said conduit to said acoustic sensor, the frequency range being selected whereby a fluid leak in said fluid conduit results in a threshold change in the preselected frequency component,
• the acoustic sensor operable to receive and sense the at least one output acoustic signal to detect the at least one said preselected frequency component or a harmonic frequency correlated to the at least one preselected frequency component,
• the processor storing program instructions executable by the processor to:
• identify in the sensed acoustic signal a threshold change in the detected at least one preselected frequency component or the harmonic frequency correlated to the at least one detected preselected frequency component by effecting a Fourier Transform or short time Fourier Transform thereon;
• and
• output at least one said control signal on detecting the threshold change in the at least one frequency component.

A control system for a steel making furnace installation including an electric arc furnace and a cooling panel thermally communicating with a sidewall portion of the electric arc furnace, the cooling panel including a conduit for receiving a cooling fluid flow therein,

• the control system comprising:
• a fluid leak detection system comprising an acoustic emitter, an acoustic sensor, and a processor electronically communicating with the acoustic sensor,
• the acoustic emitter being operable to output an acoustic signal in said cooling fluid flow for propagation therein along said conduit,
• the acoustic signal including at least one preselected frequency component or at least one harmonic frequency correlated to said preselected frequency component, the preselected frequency component selected whereby a leak in the conduit results in a threshold change in at least one frequency or frequency band of the frequency components,
• the acoustic sensor being spaced from said acoustic emitter and operable to receive and sense the output acoustic signal,
• the processor being operable to output a control signal for controlling at least one operating parameter of the steel making furnace installation,
• the acoustic emitter being provided for positioning at a first location along said conduit selected to output said acoustic signal along a central portion of said cooling fluid flow spaced from the conduit sidewall,
• the acoustic sensor being provided for positioning along said conduit at a position spaced downstream from the acoustic emitter for receiving and sensing the output acoustic signal at the central portion of said cooling fluid flow,
• the processor operable to identify in the sensed output acoustic signal, a threshold change at least one said frequency component or harmonic frequency of said frequency component by effecting a Fourier Transform or short time Fourier Transform of the sensed output acoustic signal, and
• on identifying the threshold change, effect the output of said control signal.