Salt, (sodium chloride), is great for a number of fish ailments but as far as helping a fish to heal--it's not going to do much. Won't hurt.
If the wounds are severe or if the aggression is on-going then ideally you want to separate the fish. She won't heal if the attacks continue. Keep her water pristine with frequent partial water changes. Melafix will help to speed healing.
If the wounds are NOT severe and if the aggression is not on-going, (the injured fish is still swimming where it wants in the tank and eating and is not being chased), then you may be able to get away with keeping it in the tank and just keeping the water parameters perfect. You can treat the entire tank with Melafix.
If you keep her in the main tank you might place a large fake floating plant in there temporarily. It will give her a place to hide and perhaps prevent the aggressor from getting a clean shot at her.
If the wounds develop red edges, get larger, start to erode or develop white or gray fuzz then thats a sign of infection and you'll need to treat with an antibiotic.
Robin