Probably the easiest way to remove empty  rows is to sort. All of the
empty rows  will then be together and can be deleted easilly.

If you want to maintain the row  order though... First add a column and
fill it with 1,2,3,4,5,6,7,8,9,10........n.
Then sort the rows and delete the unwanted ones. Then sort again on
the column you put in. The extra column can then be deleted as well.