By using energetic analysis method, this paper studies two sulphur aci
d manufacturig processes starting from various raw materials, i.e. sul
phur and pyrites. Following a thorough analysis, the energetical impro
vement reserves for each process phase were determined The greatest im
provement reserves are in the raw materials burning and SO3 adosrbtion
stages. Therefore technological solutions were proposed to reduce the
respective processes irreversibilities. There were also determined, f
or each technology, the whole technological flow exergetic efficiency,
considering both the sulphuric acid and steam produced. This index al
lows an energetical comparison of two or several technologies, both fo
r the same product and varoious products.