Watch your humidity levels as you are pumping a lot of moisture into the house.

You could build a decent heat exhanger. The ones sold for clothes dryers are toys. A shame to waste all that heat.

You have to design it so you can clean the lint out periodically or capture it all before the air enters the exchanger. Not rocket science. With todays energy costs worth the effort.

The plastic hoses tend to slow air and lint movement down.I have taken it for granted that it is an electric clothes dryer. You should have pipe on them and not the flexiable plastic hose with the wire to hold it in shape. Fire hazzard with lint accumulation.

Fair amount of house fires from people going out and leaving their dryer running each year.