Kargi F, Weissman J G
Department of Chemical Engineering, Biotechnology Research Center, Whitaker Laboratory No 5, Lehigh University, Bethlehem, Pennsylvania 18015, USA.
Biotechnol Bioeng. 1984 Jun;26(6):604-12. doi: 10.1002/bit.260260608.
A dynamic mathematical model has been developed to describe microbial desulfurization of coal by Thiobacillus ferrooxidans. The model considers adsorption and desorption of cells on coal particles and microbial oxidation of pyritic sulfur on particle surfaces. The influence of certain parameters, such as microbial growth rate constants, adsorption-description constants, pulp density, coal particle size, initial cell and solid phase substrate concentration on the maximum rate of pyritic sulfur removal, have been elucidated. The maximum rate of pyritic sulfur removal was strongly dependent upon the number of attached cells per coal particle. At sufficiently high initial cell concentrations, the surfaces of coal particles are nearly saturated by the cells and the maximum leaching rate is limited either by total external surface area of coal particles or by the concentration of pyritic sulfur in the coal phase. The maximum volumetric rate of pyritic sulfur removal (mg S/h cm(3) mixture) increases with the pulp density of coal and reaches a saturation level at high pulp densities (e.g. 45%). The maximum rate also increases with decreasing particle diameter in a hyperbolic form. Increases in adsorption coefficient or decreases in the desorption coefficient also result in considerable improvements in this rate. The model can be applied to other systems consisting of suspended solid substrate particles in liquid medium with microbial oxidation occurring on the particle surfaces (e.g., bacterial ore leaching). The results obtained from this model are in good agreement with published experimental data on microbial desulfurization of coal and bacterial ore leaching.
已建立一个动态数学模型来描述氧化亚铁硫杆菌对煤的微生物脱硫过程。该模型考虑了细胞在煤颗粒上的吸附和解吸以及颗粒表面黄铁矿硫的微生物氧化。阐明了某些参数，如微生物生长速率常数、吸附 - 解吸常数、矿浆浓度、煤颗粒尺寸、初始细胞和固相底物浓度对黄铁矿硫最大去除率的影响。黄铁矿硫的最大去除率强烈依赖于每个煤颗粒上附着的细胞数量。在足够高的初始细胞浓度下，煤颗粒表面几乎被细胞饱和，最大浸出率受煤颗粒的总外表面积或煤相中黄铁矿硫浓度的限制。黄铁矿硫的最大体积去除率（毫克硫/小时·立方厘米混合物）随着煤的矿浆浓度增加而增加，并在高矿浆浓度（如45%）时达到饱和水平。最大速率也以双曲线形式随着颗粒直径减小而增加。吸附系数的增加或解吸系数的减小也会导致该速率有显著提高。该模型可应用于其他由液体介质中的悬浮固体底物颗粒组成且在颗粒表面发生微生物氧化的系统（如细菌浸矿）。从该模型获得的结果与已发表的关于煤的微生物脱硫和细菌浸矿的实验数据高度吻合。
