Due to varying wastewater features of different industries. engineering processes are diversified. Therefore, the engineering process features for petrochemical, power generation, and steel industries are analyzed separately. Fig. 14 shows the engineering processes composition in petrochemical industry. It is easy to see that MBR accounts for the majority membrane process used in the industry. 75% of membrane plants use MBR alone and 13% uses MBR coupled with RO. Overall, 88% of membrane plants use MBR technology. RO is employed in 25% of the membrane plants and it is often used with MB