基于硫循环的烟气生化脱硫及硫磺回收的过程机理

以元素硫的地球化学循环为指导，系统研究硫酸盐还原菌（SRB）生化代谢产物还原性硫化物与亚硫酸根的反应过程机理及产物形态.结果表明，在生化烟气脱硫及硫回收反应体系中，pH=（4.04±0.10）、ORP=（-134±17mV）时硫磺产量最大，硫磺产率大于40%；SO₂（aq）-S^2-（aq）体系证明pH=（3.99±0.21）、ORP=（-159±40）mV、SO₃^2-/ΣS^2-物质的量比约1：1时为产硫磺最佳条件区间；S₂O₃^2-与S^2-的产硫磺反应为副反应，有利于硫磺的产生；近中性条件下硫磺的消耗归因于产多硫化物和连多硫酸盐反应的进行；SO₂（aq）-S^2-（aq）体系和生化体系的固体产物表征分析为球状高纯斜方硫，生化体系产生的硫磺被胞外多聚物粘附裹挟.

Biochemical desulfurization of flue gas and process mechanism of sulfur recovery based on sulfur cycle

Based on the geochemical cycle of elemental sulfur, the reaction mechanism and product morphology of reductive sulfide produced by biochemical metabolism of Sulfate-Reducing Bacteria (SRB) and sulfite were systematically studied. In biochemical desulfurization of flue gas (biochemical system), the largest sulfur yield (more than 40%) achieved at pH=(4.04±0.10) and ORP=(-134±17mV), but the optimal conditions for sulfur production in SO₂(aq)-S^2-(aq) system were pH=(3.99±0.21), ORP=(-159±40mV) and 1:1 molar ratio of SO₃^2- to S². In addition, the reaction of sulfur production of S₂O₃^2- with S^2- was a side reaction, which was beneficial to the production of sulfur. Sulfur consumption under near-neutral conditions was attributed to the production of polysulfide and polysulfate. The solid products of SO₂(aq)-S^2-(aq) system and biochemical system were characterized as the spherical high-purity orthorhombic sulfur. The sulfur produced in the biochemical system was adhered by the extracellular polymer.