AM-17-45 Improvements in FCCU Operation through Controlled Catalyst Withdrawals at a Marathon Petroleum Refinery

Description:

The dynamic complexity of the FCCU means there are many areas that can be optimized in order to maximize profitability and reliability. Many refiners focus on optimizing the heat balance through implementing the latest hardware innovations, such as improving the stripper efficiency or implementing a catalyst cooler. The fresh catalyst makeup rate and additive usage can also be optimized to complement the heat balance and yield profile required for maximizing the profitability of the FCCU. It is well recognized that the fresh catalyst and additives should be injected into the unit on a continuous basis throughout the day. This avoids spikes and dips in the circulating catalyst activity and ensures smooth operation in order to maximize the unit profitability. In addition, there is also an economic benefit to be realized from the continuous withdrawal of equilibrium catalyst (E-Cat) from the unit. The Marathon Petroleum Company (MPC) refinery in Garyville, Louisiana, has led the way in carrying out process optimizations as a result of continuous catalyst withdrawal, and this article summarizes their experiences.