Any time I buy a new used keg (oxymoron?), it gets the full, thorough cleaning treatment. I do the same routine to kegs every few batches. Basically, I disassemble everything and break down all the parts, replace all the o-rings, scrub the posts inside and out with a toothbrush or Q-tip. I have one of those really long wires with the thin pipecleaner-style brush on the tip, for cleaning inside the long liquid pickup tube and short little gas tube.
I fill the keg with hot water and Oxyclean and scrub it with a toilet brush. I then rinse it 2-3 times with plain, clean hot water. I reassemble everything, lubing all O-rings with keg lube. I pour in some Star San, put the lid on, and give it a good shake. Finally, I add a little pressure to the keg (5-10 psi of CO2), hook up a picnic tap line to the liquid out post, and drain some liquid through it in order to ensure the inside of the pickup tube gets sanitized. I then disconnect the beverage line and put the keg in storage until it's needed (pressurized, with StarSan in it).
On kegging day, I just vent the CO2, pop the lid, dump out the Star San, and fill it up.
Note that after I run some Star San through the line with the picnic tap, I run some plain water through the line so that StarSan isn't sitting inside that beverage line for days/weeks, as I worry what it could be doing to the plastic. I use the little 1-gallon hand-pumped pressure sprayer that's described elsewhere on this site.
As for the chilling, your options are:
- Use a jockey box - A camping cooler with a copper coil inside of it. You fill the cooler with ice water, submerging the coils in it. One end of the coil goes out the back (or front, depending on how you intend to serve the beer) of the cooler to a beverage post that connects to the liquid line coming from the keg, the other end of the coil goes out the front of the cooler to a tap from which you pour the beer. When you pour the beer, it goes through the coil in the ice water bath, gets chilled, and by the time it reaches the faucet, should be pretty cold.
- Submerge the keg in an ice water bath - Get a big plastic garbage pail or something, put the keg in it, and fill the pail with ice water. This will take a while to cool the beer down, and as the beer is served, you'll have to remove some of the ice water or else the keg could float up.
- Buy a fridge/freezer - Surf Craigslist or Kijiji and find a used fridge/freezer. I've got several, and the most I've paid for any of them was $100.
New or otherwise, a toilet brush will never enter my kegs!! And even if I rinsed it 100 times I would still never be able to drink from it again.
