To provide a source:
On an empty stomach, blood alcohol concentration peaks about one hour after consumption, depending on the amount drunk
Yes, and to be clear, a number of factors will affect how quickly alcohol enters your system: stomach contents, body weight (not including body fat), rate of consumption. But once alcohol is in your system, you can’t just purge it by vomiting. Time is the only thing that will remove it.
body weight (not including body fat)
On the contrary (same source):
Very little alcohol enters fat because of fat’s poor solubility. Blood and tissue concentrations are therefore higher in women, who have more subcutaneous fat and a smaller blood volume, than in men, even when the amount of alcohol consumed is adjusted for body weight.
This actually proves my point. “Very little alcohol enters fat because of fat’s poor solubility.” Meaning alcohol doesn’t enter fat, so body fat doesn’t lower the concentration of alcohol in the bloodstream. It’s part of TIPS certification; a lot of bartenders are taught that body weight increases your ability to consume alcohol, so they see a heavy set guy and assume he can handle more alcohol, but fat doesn’t actually affect their tolerance. A 5’8" fat guy that weighs 250 is going to have a lower tolerance than a 6’2" lean guy that weighs 250.