If you can find companies that recycle feather to make their own product, you can locate them to enquire how your load can be collected.
You can contact Re:Down because they "recycle down and feathers extracted from post-consumer goods so that they can be re-used in your products!". They must have a collection system in place.
Eric Firmann, Co-Founder of Re:Down
You will find lots of contacts from this article
Do Recycled Feathers Make Your Down Coat More Ethical?
1) Mark Galbraith, General Manager at Nau. This American company offers jackets and vests featuring feathers that have been recovered from old blankets and pillows.
2) Anne Gillespie Director of Industry Integrity at Textile Exchange, which helped create the Responsible Down Standard
3) Pamela Ravasio, a Sustainability Manager with the trade organization European Outdoor Group, said that down might have some benefits for use in compost. However, if the source of the pre-loved blanket or pillow is not known, there remains the possibility that they pose a health hazard.
Recycled down is recovered from used duvets and pillows, then cleaned and sorted like virgin down.
The Recycled Down we use is a mix of either 600- or 700-fill-power goose and duck down that is reclaimed from cushions, bedding and other used items that ...
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The Man (in Bangkok) Who Eats Chicken Feathers