Analysis of application cases of multi-technology combined treatment for typical coking contaminated site

Typical coking-contaminated sites have obvious composite pollution characteristics of polycyclic aromatic hydrocarbons (PAHs) and heavy metals, and single remediation technology is often difficult to complete the treatment. The application practice of multi-technology combined remediation has been carried out, but the site pollution characteristics and engineering technical problems applicable to the combined application technology are rarely reported. PAHs and heavy metals in the coking-contaminated sites are primarily distributed within the shallow soil, indicating compound pollution. However, there is minimal interaction between these two kinds of pollutants. Therefore, a combined remediation technology with soil leaching as its core is suitable for application due to its advantages of saving restoration cycle and cost. The main technical challenge lies in preventing and controlling secondary pollution. In the future, a synergistic approach combining soil leaching, chemical oxidation, and bioremediation technologies can be developed for environmentally-friendly restoration.