**5. Conclusion**

Algae being the main source of feedstock for the biorefinery production have helped not only in maintaining sustainability but also keeping it pollution free. Since algae considered as third generation for the production of biofuel, until now many researches have shown evidences with many positive effective work that helped both in human as well as in living environment. Thermochemical conversion process found to be a promising route as it can connect with algal based biorefinery production. Basically it consists of recovering energy for conversion from algal biomass. Mostly thermochemical processes such as gasification, combustion, pyrolysis works based on less moisture content samples but hydrothermal process compared to other processes can be proceed with wet algal biomass (high moisture content). In some of the processes, catalyst containing of chemical or biochemical are added for better result of biorefinery production in order to upgrade the bio-oil formed during the thermochemical process. Hence, though this process consists some positive effect but it also has its negative impact too where in some processes both wet and dry has its own impact along with large scale production issues. But overall, these thermochemical merit and demerit process leads to great study for research for future bio-refinery production.
