Business visa and tourist visa

Since i (Dutch male) have been working a shore in China for the last 4 months i have a multiple entry business visa.
Next month i will be sailing on a merchant ship as officer. After this i will disembark the vessel and like to go on a holiday of 1 month in China. Most propably i will disembark the vessel in China or in South Korea.
My multiple business visa is still valid, however i will be a tourist as well as a disembarking member of a ship.
is it aloud to use my business visa when i will me travling through China?
when disembarking a vessel, how many days i can stay in China and is it aloud to travel the country?