酸性工业气体的细菌脱硫

STUDIES ON BACTERIAL DESULFURIZATION OF THE H2S-CONTAINING INDUSTRIAL GASES

以软性纤维和玻璃钢蜂窝填料作为氧化亚铁硫杆菌(Thiobacillus ferrooxidans)P3-20菌株载体,制备了细菌生物膜反应器。该反应器在启动后连续运转30天左右,Fe^(2+)氧化达到平衡状态,软性填料反应器的 Fe^(2+)氧化速率是蜂窝填料反应器的三倍。在通气量为250 l/h,稀释率为0.165h^(-1)条件下,以溢流液中 Fe^(2+)氧化率≥95%为标准,软性填料反应器中 Fe^(2+)平均氧化速率的最大值为1170.87mg·L^(-1)·h^(-1)。利用细菌9K 氧化液,通过穿流栅孔板塔对石油催化干气和沼气进行脱硫,在塔板数仅为三块的条件下,H_2S 的去除率分别为71.45%和46.91%。在化学吸收过程中所形成的硫磺,易于沉淀分离,纯度达95%以上。将分离液的 pH值调至2.0后,即可进入生物膜反应器中重新氧化,循环使用。该法不需高温、高压和催化剂,H_2S 的选择吸收性高,无废料排放,整个工艺呈闭路循环。

A bioreactor was developed which contained soft fiber structure materials on which theThiobaciUus ferrooxidans P3-20 was coated.With this reactor,ferrous sulphate solution(Fe^(2+))could be oxidized continuously to ferric sulphate solution(Fe^(3+)).In the steadystate of the bioreactor operation,a maxium Fe^(2+) oxidation rate of 1170.87 mg·L^(-1)·h^(-1)was attained with the optimum aeration of 1:0.7(v/v)and the optimum dilution of 0.165h^(-1).The ferric sulphate solution absorbed H_2S which was then oxidized to elemental sulfurin the sieve-plate column.Sulfur purity up to 95% was obtained.A H2S removal of71.45% and 46.91% could be achieved with only three plate in the feed biogas treatmentand the refinerys sour feed gas,respectively.The process does not require catalysts andspecial chemicals for oxidation.Furthemore the process operates at normal temperatureand atmospheric pressure and hence eliminates the need for heat and pressurization power.