A hairdryer certainly has the capability of loosening the adhesive in many displays. Generally, if a heat gun can get the job done, a hairdryer can, as well. Just be careful not to overheat/damage the device. I'd recommend starting with a low setting to try to loosen the adhesive. If that doesn't cut it, try upping the temperature a bit. Since hairdryers are not specifically designed for this, the temperature regulation might not be quite up to snuff with the heat gun, but if you are careful it can most certainly work.
Hope this helps!
