Aggregation of sulphate-reducing bacteria and homo-acetogenic bacteria in a lab-scale gas-lift reactor

This paper discusses aspects of the formation, growth and detachment of sulphate-reducing aggregates, growing on H2/CO2 and H2/CO gas mixtures in a 4.5 L lab-scale gas-lift reactor. The biomass in the aggregates consisted predominantly of Desulfovibrio sp. and Acetobacterium sp. Our experiments with H2/CO2 showed that aggregates with pumice particles, i.e. biofilms, as well as carrier-free aggregates were formed. At pH 7.0, all the aggregates had a very hairy structure. This structure, however, was pH dependent. At lower pH-levels the aggregates became smooth. At pH-values higher than 7.0 the hairy structure became even more irregular. The predominant microorganisms were rather heterogeneously distributed throughout the aggregates at all pH-values. Growth on gas-mixtures of H2/CO led to the formation of smooth aggregates. Presence of CO also led to formation of a layered biomass structure in which the Acetobacterium sp. were more at the outside of the aggregates and the Desulfovibrio sp. were located at the inner part of the aggregates. The observed changes in the surface structure of the sulphate-reducing aggregates are related to the growth rate of the microorganisms present. A high growth rate yields a rough and hairy aggregate surface. A low growth rate yields a smooth aggregate surface, since the low growth rate of the microorganisms allows detachment of the large protrusions from the aggregate surface. The surface structure is not dependent on the type of bacteria present at the surface, i.e. sulphate-reducing bacteria or homo-acetogenic bacteria.

Download Full-text

Sulphate reduction by aggregates of sulphate-reducing bacteria and homo-acetogenic bacteria in a lab-scale gas-lift reactor

Bioresource Technology ◽

10.1016/0960-8524(95)00117-4 ◽

1995 ◽

Vol 54 (1) ◽

pp. 73-79 ◽

Cited By ~ 26

Author(s):

Renze T. van Houten ◽

Stefanie J.W.H.Oude Elferink ◽

Sandra E. van Hamel ◽

Look W.Hulshoff Pol ◽

Gatze Lettinga

Keyword(s):

Sulphate Reduction ◽

Sulphate Reducing Bacteria ◽

Acetogenic Bacteria ◽

Reducing Bacteria ◽

Gas Lift

Download Full-text

Investigation into Mechanisms of Microbial Effects on Iron and Manganese Transformations in Artificially Recharged Groundwater

Water Science & Technology ◽

10.2166/wst.1988.0080 ◽

1988 ◽

Vol 20 (3) ◽

pp. 47-53 ◽

Cited By ~ 1

Author(s):

Yan Bao-rui

Keyword(s):

Groundwater Quality ◽

Biochemical Reaction ◽

Reaction Products ◽

Injection Wells ◽

Iron Bacteria ◽

Sulphate Reducing Bacteria ◽

Prevention And Treatment ◽

Reducing Bacteria ◽

Iron And Manganese ◽

Microbial Effects

After artificial recharging of groundwater some problems occurred, such as changes in groundwater quality, the silting up of recharge (injection) wells, etc. Therefore, the mechanisms of microbial effects on groundwater quality after artificial recharging were studied in Shanghai and the district of Changzhou. These problems were approached on the basis of the amounts of biochemical reaction products generated by the metabolism of iron bacteria, sulphate-reducing bacteria, Thiobacillusthioparus, and Thiobacillusdenitrificans. The experiments showed that in the transformations occurring and the siltation of recharge wells, microorganisms play an important role, due to the various chemical and biochemical activities. A water-rock-microorganisms system is proposed, and some methods for the prevention and treatment of these effects are given.

Download Full-text