In seafood-processing industries, there are two categories of wastewaters: high
salinity wastewaters, which are produced when seawater is used as the process
water and/or when the shellfish is opened, releasing the entrapped saline water
(Soto et al., 1993) and low salinity wastewaters, obtained when fresh water is used
as the process water and no emission of saline wastewater from the products occurs
(Mendez et al., 1995). Wastewaters originating from mussel, tuna, and octopus
cooking manufacturing contain between 2.1 to 2.7 g/l SO4
2–
and 12.4 to 16.9 g/l
COD, whereas fish-meal production wastewaters contain lower sulfate (0.6 g/l
SO4
2–
) and higher COD (55.4 g/l) concentrations (Mendez et al., 1995)