I found this via google images; I'm sorting for pictures of how textiles are sorted. Currently, it looks like amateur hour is a bunch of tables, and mid-range professional operations have belts and people standing along them, so you don't need to feed the tables by hand. I don't know what a high end operation looks like -- that's what I want to know.
The article is interesting because the author's tone is really even and compassionate and his position clearly presented, also because it is a UK and Germany perspective; you can never assume that things are the same in one place as another and the changes are unpredictable.
ETA: Swiss people sorting used clothing: http://www.texaid.ch/en-us/textilerecycling/sorting.aspx
This probably is a high-end operation. Belts and headset microphones.
ETA: 2009 article about SortUK
More concerns about input streams being diverted, accusations that other participants in the industry are Behaving Badly (landfilling, illegal labor, etc.).
This one says that people have been stealing bins, that the price of the stream has gone up at the same time that volume has dropped. It also notes margin pressure in the US.
The Dutch textile recyclers are here:
Here is the Bureau of International Recycling on the subject of textiles.
Here's a hopelessly problematic opener:
"Today, clothing not only responds to practical needs; fashion has become a form of self-expression"
The author appears to believe that at some point in the mists of the past, clothing was once purely practical and fashion was NOT a form of self-expression. Ha! Probably the opposite of true, and clothing began as an impractical form of self-expression, but then we co-evolved to allow us to live in places where unadorned humanity would never have survived.
Their processing picture is belts.
Jargon: Credential Clothing is non-cherry picked clothing from a container in a, er, cherry-picked neighborhood.
I feel like this explains a lot. It's sort of like when I was a kid, and we only went to garage/yard sales in certain neighborhoods.
ETA: Numbers on employees, pounds per day, number of grades and a list of (most of) the grades
Sounds like each item is handled for maybe 15 seconds at a time, and some fraction of the items are getting multiple passes.
ETA: When items are not reusable, they can still be sorted by color and turned into yarn that does not have to be redyed.