There's actually a FAQ for the LHC (CERN approved too). In that link , you'll see your exact question with the answer (all emphasis mine),
When a proton leaves the source, it crosses the linac and reaches the PSB in a few microseconds. In the PSB it is accelerated from 50 MeV to 1.4 GeV in 530 ms,
then after less than a microsecond it is injected in the PS where it can either:
- be accelerated/manipulated/extracted in 1025 ms
- or wait for 1.2 more seconds before being accelerated, if it's part of the first PSB batch to the PS.
Then it is sent to the SPS where it waits for 10.8, 7.2, 3.6, or zero seconds whether it's part of the first, second, third, or fourth PS batch to the SPS.
The SPS accelerates it to 450 GeV in 4.3 seconds, and sends it to the LHC.
So the time it takes from the source to the exit of the SPS is between
0.53 + 1.025 + 4.3 = 5.86 seconds and
0.53 + 1.2 + 1.025 + 10.8 + 4.3 = 17.86 seconds
Then our proton has to wait up to 20 minutes on the LHC 450 GeV injection plateau before the 25 minutes ramp to high energy, and these 45 minutes dominates the transit time.
The current number of experiments per day at the LHC is zero, as it's been temporarily shut down for some revamping. I think, though, that when it was running earlier in the year there were only a few experiments done per day (on the order of 5-10) but don't quote me on this, as I'm not 100% sure--if someone has the right answer, I'll amend this statement.
From the comments from user1247, the above quoted "experiments per day" is incorrect. The particle beam is stored in the rings for 10-20 hours providing several hundred million collisions per second before the supply of protons needs to be refilled.