**8. Conclusions**

Gasifier design and process optimization for complex biomass feedstocks, in general, are very challenging due to the lack of detailed understanding of the various thermochemical reaction steps governing the conversion of biomass feedstocks under high temperature and pressure conditions. The gasification technologies described in this chapter are multiphase systems that are characterized by complex operational steps. Therefore, in order to better comprehend the complex interactions between process steps during gasification and to address the technological issues earlier described, experimental studies under systematic variation of feed specification and process parameters are required. It is also necessary to ensure proper process mapping based on experimental data from lab- to pilot-scale in order to develop a comprehensive gasification process understanding and to provide a thorough data basis for the validation of numerical simulations. This implies the development of state-of-the-art experimental techniques that are applicable under the acrid conditions of gasification technologies.
