Organic and nitrogenous matter effects on the denitrification of saline and protein-rich effluents.
The separate effect of protein concentration, nitrate concentration and carbon/nitrogen (C/N) ratio on the rate and efficiency of nitrate reduction was studied in batch reactors fed with a mixture of a synthetic substrate and a saline protein-rich salmon-plant effluent. At a constant nitrate concentration (40 mg L(-1)), the specific rate of nitrate removal decreased by 60% with increasing initial protein concentration (392 to 1900 mg L(-1)) and ammonification prevailed under these conditions; meanwhile at a constant protein concentration (1104 mg L(-1)), the specific rate of nitrate removal increased 58 times with increasing nitrate concentrations (0.5 to 78 mg L(-1)) and denitrification was the main route for nitrate reduction. The C/N ratio had an inverse effect on the specific rate of denitrification; the latter ranged from 227 to 563 [mg NO3(-)-N (g VSS d)(-1)] for a C/N ratio of 163 to 16 [mg TOC (total organic carbon) (mg NO3(-)-N)(-1)], respectively. On the other hand, the ammonia production rate was proportional up to a C/N ratio of 150.
Huiliñir
C
C
Departamento de Ingeniería Química, Fac. de Ingeniería, Universidad de Concepción, Concepción, Chile.
Martí
M Cristina
MC
Aspé
E
E
Roeckel
M
M
D000818:Animals; D019149:Bioreactors; D005398:Fisheries; D007220:Industrial Waste; D009566:Nitrates / Q000378:metabolism*; D009930:Organic Chemicals / Q000737:chemistry*; D011506:Proteins / Q000737:chemistry*; D012474:Salmon; D012965:Sodium Chloride / Q000737:chemistry
D007220:Industrial Waste; D009566:Nitrates; D009930:Organic Chemicals; D011506:Proteins; D012965:Sodium Chloride