Effects of nitrogen and phosphorus limitation on the activated sludge biomass in a kraft mill biotreatment system

• Published in: Water environment research 2006-11, Vol.78 (12), p.2303-2310
• Main Authors: Bhathena, Jasmine, Driscoll, Brian T., Charles, Trevor C., Archibald, Frederick S.
• Format: Article
• Language: English
• Subjects: Activated sludge; Applied sciences; bacteria; Biochemical oxygen demand; Biological and medical sciences; Biomass energy; Bioreactors; Biotechnology; Chemical engineering; Continental surface waters; effluent treatment; Exact sciences and technology; extracellular polymeric substances; Fundamental and applied biological sciences. Psychology; General purification processes; Industrial effluents; Industrial Waste; kraft mills; kraft pulping; Methods. Procedures. Technologies; Natural water pollution; Nitrogen; nutrient availability; nutrients; Others; Paper mills; Phosphorus; Pollution; polymers; poly‐beta‐hydroxybutyrate; Pulp & paper mills; Pulp and paper industry; Pulp and paper mill effluents; Pulp mills; Reactors; Research Papers; Sewage; Sludge; Various methods and equipments; Waste Disposal, Fluid; Wastewater; wastewater treatment; Wastewaters; Water pollution; Water treatment; Water treatment and pollution
• ISSN: 1061-4303; 1554-7531
• DOI: 10.2175/106143006X95401

Unlike wastewater, pulp and paper mill effluents are generally severely deficient in bioavailable nitrogen and phosphorus. The influence of nitrogen and phosphorus limitations on steady-state or typical pulp and paper mill activated sludge floc properties and performance was studied using a bioreactor-fed synthetic raw mill effluent and seeded with mill activated sludge. Limitation of either nitrogen or phosphorus decreased growth, five-day biochemical oxygen demand, and suspended solids removal. Nitrogen limitation greatly enhanced activated sludge floc poly-β-hydroxybutyrate (PHB), but not carbohydrate or extracellular polymeric substances (EPS). In contrast, phosphorus limitation increased total floc carbohydrate and EPS, but not PHB. The flocs showed little ability to store either nitrogen or phosphorus. Nitrogen limitation, but not phosphorus limitation, produced much more negative net floc surface charge, increasing fines, while phosphorus limitation, but not nitrogen limitation, increased the floc bound water content and surface hydrophobicity and decreased fines.