The central bank withdraws currency from circulation by issuing bills.
Tips
memory
回笼 literally means 'back into the steamer': 笼 is the bamboo 蒸笼, and cold buns go back in to be steamed again. The same picture gives 回笼觉, going back to sleep after you have already woken up.
usage
In finance the opposite of 回笼 is 投放 'to put into circulation'. Central bank reports give the day's 净投放 or 净回笼: net injection or net withdrawal of money.