Hi Tim,
Regrettably, that functionality doesn't exist right now. I can give you a "super special hidden link" that will allow you to clear your entire Requirements.cc universe - this would be a complete clearing of all of your projects and you'd need to re-upload everything from scratch, though.
We're constantly looking at ways to improve the site, and I think this one makes sense - I've recorded it for the developers to take a look at implementing it, and thanks very much for the suggestion!
If you'd like to clear your account, please send an email to support@serlio.com and we'll get that link right over to you.