title: Automated equipment for anaerobic sludge parameters determination.
abstract: Methanogenic activity, anaerobic biodegradability and toxicity are key parameters in the design and operation of anaerobic bioreactors. A large variety of methods exist for the determination of these parameters but a normalized method has not been established so far. This paper presents the development of an automated manometric system for the determination of these anaerobic sludge parameters. The system is based on monitoring the production of methane by using a pressure transducer that measures the pressure in a gas-collecting chamber of known adjustable volume, which is independent of the space where biogas production takes place. The evolution of pressure generated by the accumulation of methane relates to the conversion of COD. In this way, the methanogenic activity of the sludge can be determined, as well as the biodegradability of solids and liquid, as well as the methanogenic toxicity of compounds. The equipment permits gas sampling, as well as extraction and introduction of liquid, without losing the anaerobic conditions. Various assays have been conducted to test the reliability and reproducibility of the obtained results, showing a high level of both. The methanogenic activities obtained in the assays ranged between 0.1 and 1.8 g COD g(-1) VSS d(-1), and the biodegradability of the organic compounds tested ranged between 20 and 90%.
authors.affiliation: Department of Chemical Engineering, University of Valladolid, Paseo Prado de la Magdalena s/n, 47005 Valladolid, Spain.
authors.forename: F
authors.initials: F
authors.lastname: Fdz-Polanco
authors.forename: P
authors.initials: P
authors.lastname: Nieto
authors.forename: S
authors.initials: S
authors.lastname: Pérez Elvira
authors.forename: F P
authors.initials: FP
authors.lastname: van der Zee
authors.forename: M
authors.initials: M
authors.lastname: Fdz-Polanc
authors.forename: P A
authors.initials: PA
authors.lastname: García
mesh_terms: D001331:Automation; D001421:Bacteria, Anaerobic / Q000378:metabolism; D001673:Biodegradation, Environmental; D019149:Bioreactors; D005232:Fatty Acids, Volatile / Q000378:metabolism; D007220:Industrial Waste; D008697:Methane / Q000378:metabolism*; D011312:Pressure; D015203:Reproducibility of Results; D012722:Sewage / Q000382:microbiology; D014865:Waste Disposal, Fluid / Q000295:instrumentation* / Q000379:methods
chemical_list: D005232:Fatty Acids, Volatile; D007220:Industrial Waste; D012722:Sewage; D008697:Methane