Hi jeana, time is too limited to have a Beijing tour
from Xingang port in the same day. To do so, 70% of the possibility that you might be late for your cruise when returning back from Beijing.
Yes, it's about 3 hours away from Beijing. And there are always fogs on the way from Xingang port to Beijing. As long as the fog is heavy enough, the highway will be blocked until the road is clear again. There was even a time so far I know that the blockade lasted for almost 1 day!
If you really want to tour around, I recommond you to visit Tianjin which is also a nice city nearby Beijing. It is only 1 hour away from Xingang Port
. This tour is more available.