How long does redness disappear after a green peel? (Photo)

Looks like a chemical burn.You should seek medical treatment after such burn injury and once the skin is treated, focus on reducing post inflammatory hyperpigmentation. After Blue or Green peels, it is important to use an Opti-Ceramide cream and the best one is Elevase. 
I also recommend Pigmentation Correction Complex for PIH.
Best
H Karamanoukian MD FACS