Although you could use it as a heat source if its from an electric dryer, you would not use it if its from a gas dryer. The last thing you want in your home is carbon monoxide. In addition to the C0, all the extra water vapor in the winter is a bad thing. It will eventually cause rot in your wood structure and mold growing throughout the home. The only real way to capture the heat would be with a heat exchanger. This is a device that allows the heat to be transferred without exchanging the moisture or the C0. Since it doesn't really exist, you would have to have something like that manufactured.
Good Luck
Ray
Master Plumber