## 4 Conclusions and Prospects  
The treatment of landfill leachate currently faces both challenges and opportunities. This article provides an overview of the characteristics and composition of landfill leachate, summarizes existing treatment methods, and compares their respective advantages and disadvantages. While multiple treatment technologies have been implemented in this field, each exhibits unique advantages and limitations. From an economic perspective, physical methods stand out for their low cost and operational simplicity. In terms of treatment efficacy, chemical oxidation demonstrates strong performance, yet its high expenses and risk of secondary pollution remain concerns. Under green development principles, biological methods show distinct advantages--particularly in removing nitrogen- and carbon-containing organic compounds--though their effectiveness in degrading refractory substances remains limited. Membrane separation technology has achieved notable success in leachate treatment, but challenges such as membrane fouling, contamination risks, and high operational costs hinder its widespread adoption. Moreover, as the variety of emerging contaminants detected in landfill leachate continues to grow, traditional treatment technologies struggle to effectively remove them. Compounded by the limitations of single-process approaches, which fail to address the diversity and complexity of pollutants, hybrid treatment systems integrating physical, chemical, and biological processes have emerged as a critical strategy to resolve these challenges. Despite ongoing advancements, landfill leachate treatment still faces unresolved challenges, including emerging contaminants and efficiency-cost trade-offs in existing technologies. Given its high environmental risks, the field urgently requires innovative, \begin{table}
\begin{tabular}{c c c} \hline \hline
**Technologies** & **Advantages** & **Disadvantages** \\ \hline \multirow{5}{*}{Physical method} & \multirow{5}{*}{Adsorption} & \(\bullet\) Simple operation & \(\bullet\) High adsorbent costs \\  & & \(\bullet\) Adsorbent reusability & \(\bullet\) Complex regeneration protocols \\  & & \(\bullet\) Effective for low-concentration & \(\bullet\) Limited efficacy for \\  & & organics and heavy metals & high-concentration wastewater \\  & & \(\bullet\) Cost-effective & \(\bullet\) Limited effectiveness against soluble \\  & \(\bullet\) Minimal infrastructure requirements & organic compounds \\  & & \(\bullet\) Efficient removal of suspended solids & \(\bullet\) Generates sludge requiring \\  & & and select organics & additional treatment \\ \hline \multirow{5}{*}{Advanced oxidation progress} & \multirow{5}{*}{Aerobic} & \(\bullet\) Rapid degradation of & \(\bullet\) Elevated operational costs \\  & & refractory organics & \(\bullet\) Secondary pollution risks \\  & & \(\bullet\) High reaction efficiency & \(\bullet\) Performance instability under \\ \hline \multirow{5}{*}{Biological method} & \multirow{5}{*}{Anaerobic} & \(\bullet\) Low operational costs & \(\bullet\) Inefficient for refractory organics \\  & & \(\bullet\) Effective organic matter and & \(\bullet\) Performance instability under \\  & & ammonia nitrogen removal & fluctuating water quality \\  & & \(\bullet\) Suitable for high-organic wastewater & \(\bullet\) Prolonged startup period \\  & & \(\bullet\) Energy-efficient with biogas & \(\bullet\) Sensitive to temperature/ \\  & & recovery potential & \(\bullet\) PH variations \\  & & \(\bullet\) Post-treatment effluent requirements \\ \hline \multirow{5}{*}{Membrane technology} & \multirow{5}{*}{Membrane technology} & \(\bullet\) High separation efficiency & \(\bullet\) Membrane fouling susceptibility \\  & & \(\bullet\) Superior effluent quality & \(\bullet\) High membrane replacement costs \\ \cline{1-1}  & & \(\bullet\) Adaptation to high- & \(\bullet\) Significant energy demand \\ \cline{1-1}  & & \(\bullet\) Significant energy demand \\ \hline \hline \end{tabular}
\end{table} 
Table 8: Advantages and disadvantages of treatment technologies [170].