try this!
suppose your table name is temp
select a.id, convert(varchar(10), a.[date], 101),
datediff(mi,a.date, b.date) / 60
from temp a
inner join
temp b
on a.id = b.id
and convert(varchar(10), a.[date], 101) = convert(varchar(10), b.[date], 101)
and a.seq < b.seq
hope this will help.
meydz