This won’t work. Since you aren’t exhausting the heat from the room, the net effect will be to simply heat the room up. This is basic thermodynamics.
BTW, the same thing will happen if you try to run an air conditioner in a room without exhausting the heat out of the room.
I’ve used a dehumidifier unit in my basement, and if the space is closed up, it really heats the room up dramatically while drying things out. Also, you have to run it for much longer than a short “blast” to noticeably lower the humidity.