This research followed acetate carbon (C) uptake, metabolism, and fate through a typical modern Kraft pulp and paper mill AS system. Freshly collected mill biomass (AS floc suspensions) was placed under conditions representing four key phases of AS biotreatment: (1) initial acetate uptake by aerated starved AS; (2) ongoing acetate uptake; (3) aerobic metabolism of acetate-loaded AS in acetate-stripped effluent; and (4) anaerobic, settled biomass metabolism. Conditions mimicked the mill system as closely as possible. Acetate carbon uptake kinetics and conversion to CO2, growth products, PHB, and secreted metabolites in each of the four phases were measured. The role of PHB synthesis in the initial stripping of acetate from mill effluent and the PHB production potential of this mill AS were also investigated. / Results showed that acetate was rapidly taken up by high-affinity systems in the AS. During the initial exposure of mill-starved AS, acetate greatly stimulated AS-O2 uptake, and was quickly converted to PHB and CO 2. Upon depletion of available effluent acetate, as occurs in the downstream sections of the aeration tank, O2-uptake rates decreased and the acetate-C stored in AS-PHB was slowly released as CO2, and partly used for growth. Under secondary clarifier-like anaerobic conditions, the AS released virtually no CO2. However, substantial amounts of PHB were used for growth under anaerobic conditions and a small proportion of the original acetate C exited the cells as organic acids.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.82401 |
| Date | January 2005 |
| Creators | Pouliot, Cédrick |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Master of Science (Department of Natural Resource Sciences.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 002211368, proquestno: AAIMR12516, Theses scanned by UMI/ProQuest. |
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