Hurse Timothy J, Keller Jurg
Department of Microbiology and Parasitology, School of Molecular and Microbial Sciences, The University of Queensland, Brisbane, Qld 4072, Australia.
Biotechnol Bioeng. 2004 Jul 5;87(1):14-23. doi: 10.1002/bit.20062.
The performance of a sulfide-removal system based on biofilms dominated by green sulfur bacteria (GSB) has been investigated. The system was supplied with radiant energy in the band 720-780 nm, and fed with a synthetic wastewater. The areal net sulfide removal rate and the efficacy of the incident radiant energy for sulfide removal have been characterized over ranges of bulk sulfide concentration (1.6-11.5 mg L(-1)) and incident irradiance (0.21-1.51 W m(-2)). The areal net sulfide removal rate increased monotonically with both increasing incident irradiance and increasing bulk sulfide concentration. The efficacy of the radiant energy for sulfide removal (the amount of sulfide removed per unit energy supplied) also increased monotonically with rising bulk sulfide concentration, but exhibited a maximum value with respect to incident irradiance. The maximum observed values of this net removal rate and this efficacy were, respectively, 2.08 g m(-2) d(-1) and 2.04 g W(-1) d(-1). In-band changes in the spectral composition of the radiant energy affected this efficacy only slightly. The products of sulfide removal were sulfate and elemental-S. The elemental-S was scarcely released into the liquid, however, and reasons for this, such as sulfur reduction and polysulfide formation, are considered. Between 1.45 and 3.85 photons were needed for the net removal of one electron from S-species. Intact samples of the biofilm were characterized by microscopy, and their thicknesses lay between 39 +/- 9 and 429 +/- 57 microm. The use of the experimentally determined rates and efficacies for the design of a pilot-scale system is illustrated.
对基于以绿硫细菌（GSB）为主导的生物膜的硫化物去除系统的性能进行了研究。该系统被提供720 - 780 nm波段的辐射能，并被投喂合成废水。在总硫化物浓度范围（1.6 - 11.5 mg L(-1)）和入射辐照度范围（0.21 - 1.51 W m(-2)）内，对面积净硫化物去除率和入射辐射能对硫化物去除的功效进行了表征。面积净硫化物去除率随入射辐照度增加和总硫化物浓度增加而单调增加。辐射能对硫化物去除的功效（每单位供应能量去除的硫化物量）也随总硫化物浓度升高而单调增加，但相对于入射辐照度呈现最大值。该净去除率和该功效的最大观测值分别为2.08 g m(-2) d(-1)和2.04 g W(-1) d(-1)。辐射能光谱组成的带内变化对该功效影响很小。硫化物去除的产物是硫酸盐和元素硫。然而，元素硫几乎没有释放到液体中，并对其原因进行了探讨，如硫还原和多硫化物形成。从硫物种净去除一个电子需要1.45至3.85个光子。通过显微镜对生物膜的完整样本进行了表征，其厚度在39±9至429±57微米之间。说明了如何将实验确定的速率和功效用于中试规模系统的设计。
