Simulation studies enable the asset owners and the system designers to gain a better insight into the design and operation of their facilities. In the downstream process, simulation studies are used to design, develop, analyze, and optimize various processes. Analyze existing processes and Define the process parameters used in the design of future processes. Although simulation techniques vary depending on the size and complexity of the process, along with the software being used to perform the modelling, which is looked upon by the operators in the plant with the help of various different tools available in the market.