Any ideas how to get the creases out of a new curtain (without ironing it)?

I bought some new curtains and they came in a packet, folded up. They are made of a polyester blend of some sort. Unfortunately, they are really creased, where they were folded into the packet.

My neighbor told me to pop them into the washer and that would do the trick. It didn’t. I put them in the dryer and now, they are not only creased, they are also wrinkled. I don’t think they are heavy enough that they will “iron out naturally” when hung on the curtain rods.

I have had to iron curtains before…and these are so huge and there is so much fabric, I just don’t want to spend hours and hours doing this. (I have eight huge panels to do…9 ft by 9ft each!) I also don’t want to take them to a dry cleaners because they won’t get done on time.

Does anyone have any ideas how to get these creases/wrinkles out…tips, tricks…etc? Without having to resort to ironing them one by one?

Thank you!