**2.3 Gasification**

Gasification is another of the thermochemical conversion method, used to produce gaseous material from OSR [11]. Gasification flow diagram can be observed in **Figure 4**. Though, the produced gaseous material can be used for heat, electricity, methane and hydrogen generation [15]. However, gasification not only produces gaseous products but also produces bio-chemical liquids. In general, gasification occurs at high temperature value, tar content in the gas is very low, and the cleaning process is very simple [16].
