Sounds to me like she's broody...they don't need a rooster for that instinct...they don't know the eggs aren't fertile. What breed is she? Some are more prone to broodiness than others. Just go ahead and take the eggs...once they're gone she'll likely leave the nest.
Yep she's broody. Put her in a dog crate with some pine shavings or straw and give her food and water. Let her out a couple of times a day to stretch her legs, but she will probably head back to her nest box. Place her back in the dog crate for a minimum of 3 days until she quits returning to brood. Some broodies can't be quite stubborn and it may take a week or more. Just don't let her have any eggs to sit on.