**5. Conclusion**

Dry anaerobic digestion is appropriate for treatment of agricultural waste with high TS content. Optimization of C/N ratio, F/I ratio (or organic loading rate), and TS content is key to avoid failure of digestion. Several batch and continuous dry digestion technologies have been already applied in practice, while new techniques have been also proposed. Solid digestate is beneficial to supply nutrient into the soil and improve soil properties. On the other hand, nitrate leaching is one of the concerns of the digestate application. Digestate C/N ratio adjustment by mixing with crop residue can mitigate nitrate leaching. In addition, it can also mitigate root-knot nematode. More study is needed to optimize dry anaerobic digestion and digestate use for sustainable agricultural waste management.
