液相氧化脱除H_2S过程中铁离子溶液的生物法再生

以沸石为填料用吸附法固定氧化亚铁硫杆菌,建立了固定化生物反应器,对铁离子溶液进行再生,考察了空气流量和循环液喷淋量对Fe2+氧化率的影响。实验结果表明,在空气流量0.50m3/h、循环液喷淋量1.0L/h、初始pH1.6、温度30℃、初始Fe2+质量浓度8.25g/L的条件下,14h后Fe2+的氧化率可达95.18%,Fe2+的平均氧化速率为0.56g/(L.h)。利用再生的铁离子溶液在化学反应器中进行脱除H2S的实验。实验结果表明,当入口气体中H2S质量浓度为4.0g/m3时,运行250h后,脱硫效率从开始时的99.81%降为98.01%,出口气体中H2S质量浓度从7.80mg/m3增加到82.00mg/m3。为保持脱硫效率的稳定,需定期向铁溶液中补加Fe2+以维持铁离子溶液中Fe2+含量的基本稳定。

Regeneration of Ferric Ion Solution by Biological Method in Liquid Oxidation for Removing H2S

In order to remove H2S from gas,an experimental apparatus with an immobilization bioreactor and a bubble column was established.H2S was removed in the bubble column with Fe3+ solution as absorbent and itself was reduced to Fe2+ simultaneously,and then the latter was oxidized in the bioreactor with zeolite as filler and thiobacillus ferrooxidan as oxidant. Effects of air flow rate and cyclic spraying liquid flow rate on oxidation rate of Fe2+ were investigated. Under optimal conditions of immobilization bioreactor:air flow rate 0.50 m3/h,cyclic spraying liquid flow rate 1.0 L/h,initial pH 1.6,temperature 30 ℃,initial Fe2+ mass concentration 8.25 g/L and time 14 h,95.18% of Fe2+ can be oxidized and average oxidation rate is 0.56 g/(L·h).When inlet H2S mass concentration was 4.0 g/m3 and after the running was carried out for 250 h,H2S removal efficiency decreased from initial 99.81% to 98.01% and outlet H2S mass concentration correspondingly increased from initial 7.80 mg/m3 to 82.00 mg/m3.In order to maintain high H2S removal efficiency,Fe2+ should be added to the solution regularly to keep the stability of Fe2+ mass concentration.