One of the biggest hurdles I came across when switching to all-grain was learning how to sparge. I honestly still don't think I do it 100% correctly. There are very detailed descriptions online, but they are pretty confusing if you haven't done it before. I'd love to see a detailed, easy to understand explanation of sparging, the different techniques, tips, pitfalls, etc. And where the word "sparge" came from.
Sparge means "sprinkle".
The purpose of sparging is to rinse all the sugars out of the mash. In concept, that's really all you are doing - rinsing your grain bed.
It also halts enzymatic activity because alpha and beta amylase become denatured around 170° F. The benefit is if you are really good at mashing you know exactly when to stop so your malt flavor profile is where you want it.
There are a few "right" ways to do it and the measure of how well you sparge depends entirely on the targets you set for the mash. Answering these questions help you decide what method to use:
You should vorlauf before each of these (see below).
No-sparge is exactly what it sounds.
It has a few advantages, primarily its simplicity and that you are never in danger of extracting tannins from the grain husk. It is the least efficient, meaning some desirable sugars remain in the grain. The less efficient you are, the more grain you need to use.
Batch sparging is the next simplest.
This method is less labor intensive and quicker than continuous sparging. It also eliminates channeling - a concern if you have a single pick-up (like a braided hose) in the bottom of your tun. The efficiency of batch sparging falls somewhere between no-sparge and fly, but is is fairly close to the higher end of efficiency.
Fly sparging works best with an automated system.
Using continuous sparging you can get upwards of 85% efficiency. That means of all the sugars that you could get out of your grain, you extracted eighty-five percent of them. Fly sparging requires another piece of equipment, however it is easy to make. The geometry of your mash tun and the wort pick-up should not promote channeling because the wort is always moving down the grain bed.
One step that is technically not sparging, but comes between mashing and sparging, is vorlauf. This is simply removing some wort from the mash tun drain and gently returning it to the top. By recirculating the wort you set the gain bed up to filter out husks and other larger particles. Vorlauf increases the clarity of your beer because those bits never make it to the kettle. A pump is the easiest way to do it, but you can use a pitcher, just don't disturb the grain bed. Recirculate until you stop seeing floaties in the return.
Here is what I do and I find it works really well.
I have a sparge arm I built out of copper tubing that is shaped in a flat spiral (hope that makes sense).
I balance the out flow with the sparge, keep about 1-2" of water over the grain bed at all times and I average about 1gal in the kettle per 12min.
Plain simple, easy to follow.
Now, ha you knew there was more.
I have recently started playing around with batch sparging which I absolutely love but your efficiency goes right in the crapper and you have to compensate for it with increased grain bills. So you have to decide if you want to spend a couple extra dollars on grain and save an hour or not.
My efficiency at home is around 75-80 when batch sparging. At the brewery, I am getting about 88%, which is nutz. My IPA turned into an Imperial IPA, the easy drinking Pale turned into an IPA, etc.
Just remember that slow is good. If you sparge and run off too fast you'll drag all those nasty undesirables out of your mash and into your kettle. If you're using some form of mash plate or filter you could end up blocking that too. If you're able to you should always recirculate your wort back into your mash to clarify it. it'll smooth the process out for you.