Jarosite precipitates formed in iron oxidising bioreactors have been shown to harbour iron-oxidisers. The aim of this study was to develop an iron oxidising bioprocess where microorganisms are retained solely on biogenic jarosite particles. Based on preliminary experiments using a fluidised-bed bioreactor (FBR), the formed jarosite particles started to disintegrate and wash out at upflow velocities of ≥0.21 cm/s. Therefore, the generation and use of biogenic jarosite carrier was studied in an expanded-bed bioreactor (J-EBR) with an upflow velocity of 0.19 cm/s. Inside J-EBR, the jarosite particles formed granules of 0.5–3 mm containing 200–460 mg/g of attached biomass. The performance of J-EBR was compared with an activated carbon biofilm FBR at 0.82 cm/s upflow velocity (AC-FBR). At 35 ± 2 °C with a feed ferrous iron concentration of 10 g/l, the highest obtained iron oxidation rate of J-EBR (6.8 g/l/h) was 33% lower than that of AC-FBR (10.1 g/l/h). This was likely due to the 80% lower recirculation rate and subsequently higher oxygen mass transfer limitation in J-EBR compared to AC-FBR. The present study demonstrates that biogenic jarosite can be used for retainment of iron oxidising biofilms in expanded-bed bioreactors that oxidise iron at high rates.

已经证明在铁氧化生物反应器中形成的铁矾沉淀物具有铁氧化剂。这项研究的目的是开发一种铁氧化生物过程，其中微生物仅保留在生物黄铁矿颗粒上。根据使用流化床生物反应器（FBR）进行的初步实验，形成的黄钾铁矾颗粒开始崩解并以≥0.21cm / s的上流速度冲洗掉。因此，在膨胀床生物反应器（J-EBR）中以0.19 cm / s的上流速度研究了生物型黄钾铁矾载体的产生和使用。在J-EBR内部，黄铁矿颗粒形成0.5-3 mm的颗粒，其中包含200-460 mg / g附着的生物质。将J-EBR的性能与活性炭生物膜FBR在0.82 cm / s的上流速度（AC-FBR）下进行了比较。在35±2°C，进料亚铁浓度为10 g / l的情况下，J-EBR的最高铁氧化率（6.8 g / l / h）比AC-FBR（10.1 g / l / h）低33％。这很可能是由于与AC-FBR相比，J-EBR中的再循环率降低了80％，并且随后的氧气传质限制更高。本研究表明，生物黄铁矿可用于在高速率氧化铁的膨胀床生物反应器中保留铁氧化生物膜。