[en] The reduction of high concentrations of gypsum (up to 110 kg/m(3)) is investigated in a two stage immobilised cell bioreactor. The first stage is mainly colonised by a consortium of acidogenic bacteria and sulphate reducing bacteria oxidising volatile fatty acids with more than 2 carbons (mainly, butyrate and propionate). The gypsum consumption rate is rather high (ii kg/m(3).day). Most of acetate remains unconverted in this first stage. It is partially converted in the second stage (residence time : 12 days) which is predominantly colonised by acetate oxidising bacteria The gypsum consumption rate is much lower than in the first stage : 3 kg/m(3).day. With both stages, it is possible to reach an almost complete conversion of gypsum with an overall capacity of 6.1 kg gypsum/m(3).day. We propose also a very simple model to describe the different transformation rates. It allows us to clearly identify the activity levels of the different types of sulphate reducing bacteria in both stages. Copyright (C) 1996 IAWQ.
Disciplines :
Chemical engineering Biotechnology Environmental sciences & ecology
Author, co-author :
Deswaef, Sophie
Salmon, Thierry ; Université de Liège - ULiège > Département de chimie appliquée > Département de chimie appliquée
Hiligsmann, Serge ; Université de Liège - ULiège > Département des sciences de la vie > Biochimie et microbiologie industrielles
Taillieu, Xavier
Milande, Nicolas; BERTIN S.A. Tarnos, France
Thonart, Philippe ; Université de Liège - ULiège > Gembloux Agro-Bio Tech > Gembloux Agro-Bio Tech - Biochimie et microbiologie industrielles
Crine, Michel ; Université de Liège - ULiège > Département de chimie appliquée > Génie chimique - Opérations physiques unitaires
Language :
English
Title :
Treatment of gypsum waste in a two stage anaerobic reactor