It is possible to make a round trip but may not have enough time to see some important sites. After you arrive in Tianjin, take a taxi to Tianjin Railway Station try to catch the train C2018 at 9:30am to Beijing South Railway station at 10:00. It may takes one hour from the port to Tianjin Railway Station and the taxi fare is 80-100 Yuan. Take taxi to the Forbidden City, Tiananmen Square and to Qianmen, they are closed to each other. There are some hutongs in qianmen area. That is enough for the time, I think.

Mr Colin: Thank you for your helpful reply. We think that we will use our time in Tianjin to see the local sites instead of trying to get to Beijing. Will it take 60 minutes to travel from the port to the city of Tianjin where there is nice sightseeing?
Again, thank you for your help.
Steven

Yes, it will take you about 40~60 minutes by taxi to get to the sightseeing, such as the Ancient Culture Street.

Thanks for the info. Will there be taxis at the port? And I may assume that the fare would be around 80-100 Yuan?
Could you advise us regarding obtaining a taxi from the Ancient Culture Street? Would a taxi driver at the port area wait several hours for us while we did some sightseeing and then get us back to the ship?
Instead of taking a taxi into Tianjin, I am beginning to think we might just remain on the ship....I'm not very confident about getting a taxi back to the port from Tianjin.
Thank you your help.

Hi, Ms steven. Do not worry, you have sufficient time to have a see Tianjin. Or you may try public transportation, like light rail, or take a taxi from the port to Tanggu Station and then use speed train to Tianjin Railway Station. It is quite easy to take taxi from the port to Tanggu and from Tianjin Railway Station to the street. The driver may not wait you when you finish sightseeing. You can talk with the driver if you can pick you up at a certain time at some place to sent you back?!