Research progress on remediation of chlorinated aliphatic hydrocarbon contaminated groundwater by zero-valent iron combined with microorganisms

Abstract

Chlorinated aliphatic hydrocarbons (CAHs) are widely used as chemical raw materials, but carcinogenic, teratogenic and mutagenic toxic for human health. When CAHs enter the groundwater during the production process because of irregular leakage or discharge, they will cause groundwater contamination, which will be harmful to human life health and ecology environment. Up to now, many functional materials, especially zero-valent iron and its composite materials, have been applied to remediate CAHs contaminated groundwater, and the combined application with microorganisms can be of good effects. In this paper, the function types and mechanisms of ZVI composite materials and microorganisms applied to remediation of CAHs contaminated groundwater were summarized, and the coupling mechanisms of ZVI composite materials combined with microorganisms to remove CAHs in polluted groundwater were emphatically summarized. Meanwhile, the application examples of biostimulation, bioenhancement, and sulfate-reducing bacteria were analyzed to provide reference for the further improvement and application of remediation technology for CAHs contaminated groundwater. The further researches on remediation of CAHs polluted groundwater should focus on the preparation of new functional ZVI or other composite materials and excavation of the microbial resources and applying them to practical treatments of comtaminated groundwater. It also should explore the combined mechanism between environmental functional materials and bioremediation. It was also necessary to pay attention to the relationship between the complicated components of groundwater and the variation of the original environment in the process of remediation, and to emphasize on the computational simulation of field or the other related studies.

Keywords

• zero-valent iron
• microorganisms
• cahs
• groundwater
• combined remediation