Publication Details

Reference Category Journals
DOI / URL link
Document Shareable Link
Title (Primary) Injection of hydrogen gas stimulates acid mine drainage treatment in laboratory-scale hydroponic root mats
Author Richter, J.; Wiessner, A.; Zehnsdorf, A.; Müller, J.A.; Kuschk, P.;
Journal Engineering in Life Sciences
Year 2016
Department UBT; UBZ;
Volume 16
Issue 8
Language englisch;
POF III (all) T41;
Keywords Acid mine drainage; Constructed wetland; Dissimilatory sulfate reduction; Hydrogen; Rhizodeposition
UFZ wide themes RU3;
Abstract he environmentally benign disposal of acid mine drainage (AMD) is still a technical challenge. In the present study, artificial AMD was treated in a laboratory-scale floating hydroponic root mat of soft rush, Juncus effusus. This ecotechnological system was operated with hydrogen injection and water recirculation but without an external carbon supply. It achieved a mean increase of ΔpH = 3.3 up to pH ≈ 8.2, high sulfate removal of up to 87%, and efficient removal of iron (100%), aluminum (99.8%), manganese (97.4%), and zinc (99.6%). Sulfide was not detected in the outflow. Treatment performance correlated with the amount of hydrogen loading. Daily oscillations of the redox potential up to amplitudes of ΔEh ≈ 450 mV in a mean range of Eh ≈ −150 to +300 mV indicated a correlation of plant physiology and removal processes. Apparently, sulfate and metal removal were the result of chemolithotrophic microbial sulfate reduction supported by the externally provided H2 and chemoorganotrophic sulfate reduction driven by rhizodeposits. Bicarbonate generated in the microbial transformation of such plant-derived organic carbon contributed to pH neutralization. The effluent's pH increase was governed further by recirculation of the treated AMD. The flow regime and the injection of hydrogen at the ground of the root mat caused concentration gradients where the most efficient removal occurred in the deepest zone of the root mat. Further investigations should target long-term stability, plant growth dynamics, load variations, balances of carbon and sulfur, the removal of H2S and metal precipitates from the system as well as efficient hydrogen supply.
ID 17565
Persistent UFZ Identifier
Richter, J., Wiessner, A., Zehnsdorf, A., Müller, J.A., Kuschk, P. (2016):
Injection of hydrogen gas stimulates acid mine drainage treatment in laboratory-scale hydroponic root mats
Eng. Life Sci. 16 (8), 769 - 776