Excessive Blow-off

I brewed a one gallon batch of barley wine (og: 1.136!) and at about 16 hours there is a fatty layer of trub and about a quart (1/4 of my total volume) of blowoff in the blowoff container. I split up the excess, stashed some in the fridge and dumped the rest.
Now, overnight the blowoff container has about another quart of blowoff, with lots of foamy foam.
Questions:
If I had sanitized my blowoff container and had some sanitizer in the bottom, would it be a bad idea to add the blowoff back to my primary once the fermentation has calmed down?
What is the cause of so much liquid disappearing out the tube?
It's obviously a very active ferment, but should I chalk the loss up to just that, a loss? Or is there any thing I can do to not end up with a pittance of delicious barley wine?

Personally, I wouldn't combine it back in. If nothing else becaue of oxidation. I assume this will be aging for quite a while since it's a barley wine, and I wouldn't want to wait all that time just to have it taste like cardboard. Next time, leave plenty of headspace in the fermenter, keep your temps down and perhaps try some fermcap.

What is fermcap?

Niglodamus said:

What is fermcap?

Click to expand...

They sell it at any LHBS. It keeps the krausen down and helps reduce blow off. I've had good results with it. I put 4 or 5 drops into a 5 gallon batch.

Like BBL Brewer said leave plenty of headspace. That's a high gravity brew and will need plenty of room. Hope it turns out good.

Thanks for the input. I did leave a good amount of headspace, apparently not enough though. When I got home yesterday, the blowoff container was again half full and fermenting, so I threw an airlock on it, and set it aside, why not. The main fermenter looks calm, but only a little more than half remains, oh well. I'll definitely be doing a larger batch next time.