There are lots of different areas you could go into with a social work degree either with in adults or C&F in:
(i only know C&F):
Field SW - LAC, CIC, Referral and assessment etc.
Child protection, leaving care work , residential work, preventative work, drugs and alcohol work, hospital SW, domestic violence work, CAMHS.....
All will have different hours dependant on team and location (but generally 9-5ish)
Some of the roles have A LOT of travelling involved - particularly with in LAC as the yp could be placed miles away.
Time away from the desk totally depends on the role you choose - however all will involve (obviously) a lot of face to face work out of the office.
Agree with Crome - a competitive market out there !! and the future is looking iffy - with talk of out souring all except statutory teams.