Do I need a Transit visa in this case

I am a citizen of Algeria.
I have a flight from warsaw, Poland to PVG, China than to Hong kong but I have this booking on 2 seperate itinerary WAW-PVG with Austrian Airlines and PVG-HKG with Spring Airlines
I am eligible for free transit? I will be leaving the shanghai airport within 24 hours.
arrive to shanghai at 5:20a.m estimated depart to Hongkong at 1:20p.m
on the way back will be the same but I will leaving the airport as I want to book a hotel in shanghai and than day after take my flight back to europe ( transit less than 24 hours ) all transits will be made by air.
Do I need a Transit G type or just I need to apply for Temporary permit.
Thank you in advance.