According to About.com, most laundromats have commercial-grade machines that are properly sized for washing and drying bulky bedding. Most household washers and dryers cannot accommodate a queen-size comforter, but most commercial-grade washing machines can handle up to 75 pounds.
Not all comforters require the same care. A home washer and dryer may be able to handle a thin comforter, but a thick, fluffy comforter may require special cleaning. Review the washing instructions on your queen-size comforter, as some may be made of special fabric or filling that requires dry cleaning or other special care. Toss a few clean tennis balls in the dryer with your comforter to increase its fluffiness.