[Remediation of polycyclic aromatic hydrocarbons in non-fluid medium with immobilized microorganism technique]

The remediation of polycyclic aromatic hydrocarbons (PAHs) in non-fluid medium is a difficult and urgent task for environmental scientists. Due to the particularities of non-fluid medium, conventional techniques cannot work effectively, while bioremediation techniques using free microorganism also have many limitations that restricted the use of microorganism in removing PAHs from non-fluid medium. Immobilized microorganism (IM) technique is a proven approach in increasing the stability of microorganism under unfavorable conditions, which can not only provide a special microenvironment to protect dominant microorganisms from the malignant competition of aboriginal microorganism, but also improve the tolerance against toxic compounds in environment. Biodegradation using immobilized cells has been widely investigated for numerous toxic compounds in fluid medium such as in wastewater, or in half-fluid medium such as in slurry. In this paper, based on analyzing the characteristics of IM technique and its feasibility, the problem and development of future research were presented, and the new technique using IM to remediate PAHs in non-fluid medium was put forward.