There's a few ways you could go about it.
Along with your idea of starting without fire, you could make a general circus club and slowly incorporate fire into that. That's if you've got enough people doing general circus things (juggling, etc.)
The one at my Uni (Macquarie, Sydney) grew out of fire-spinners needed for Conception Day (just another excuse to party). So if you've got any up-and-coming events, could take off on that basis.
I think at any rate you've got better luck getting a club together first, and then submitting it to the Student Council. I'd imagine it's easier for them to say "no" to one person than to many.
The experience with our club wasn't too bad, however the Student Council was a little uptight about knowing the names of everyone involved for insurance purposes. Pretty understandable.
Best of luck to you, and even if you get an official "no", doesn't mean you can't set a weekly meet and get everyone to bring a bit of kero. =))