Yes, but you can only link the Read app to one set of institutional access credentials at a time.
So, if you have set QUB as your institution, and want to switch to your Healthcare Library access, you will need to press and hold QUB in the app's Institutional Access settings and delete it, before changing your institution to the Healthcare Library of Northern Ireland (or any other institution to which you belong).
Do this in reverse if you want to switch from Healthcare Library access back to QUB.