Can I get a 72 hr transit Visa.

I arrive Beijing Sept. 30th, 2pm and board a ship for 6night cruise the following day (Tianjin], the ship departing approx. 5pm Oct 1st. The ports of call are in Japan and returns to Tainjin Oct 7 early am. I wish to stay in Beijing for 3 days and then depart for home in Canada Oct 10 at 4pm.

Do I need a Visa or will I be eligible for a 72 hr free transit the first stay and a 144 hr free transit the second stay?