Improve Amine system reliability
Today, many refineries are finding that their amine systems are struggling to handle increased acid gas loads as a result of low Sulphur gasoline and diesel production. Thus, it is critical to find a suitable filtration solution to increase the plant’s reliability factor.
The refinery has one major goal to achieve: to remove particulate and liquid contaminants from entering the amine circuits due to the expansions in existing refineries. There has been a paradigm shift in crude diets to heavier and sourer “opportunity crudes”, and this has increased the amounts of stress on amine and Sulphur plants. Direct results have translated to increase corrosion products, liquid hydrocarbons and organic acids making their way into amine units.
Amine cleanliness plays an important role on the overall plant performance and must be reduced or eliminated to ensure reliable plant operation and environmental compliance. To combat this, plants have previously opted for different filtration and separation methods to tackle common contaminants. Good practices that are generally accepted are that suspended solids in an amine circuit should be kept below 1ppmw and liquid hydrocarbons and organic acids must be reduced to as close to zero as possible.
Particulate matter found in amine solutions are corrosion by-products. These are the three steps to achieving an efficient liquid/liquid separation:
- Pre-filtration: A rich side, full-flow pre-filter is essential to protect and provide maximum operating life to the liquid/liquid coalescer. It also prevents the passage of suspended solids that may deposit downstream equipment such as rich/lea heat exchangers etc.
- Coalescence: The two-phase liquid emulsion enters the coalescing element and flows inside-to-outside. This is where small, suspended droplets of the dissimilar fluid coalesce, and the emulsion moves through the proprietary, specifically formulated medium.
- Separation: The coalesced dispersed phase separates in the setting zone of the coalescer housing. Due to the density difference in the two phases, these separated liquids exit through separate drain and outlet connections.
The truth behind this process that no one tells you:
Undoubtedly, the most important benefit refineries wish to gain is an increase in the overall reliability of the amine system and Sulphur plant. While the system’s ability to allow for quick recovery after a particulate contamination incident- which keeps the system performing at capacity- is the primary benefit, the flipside of the same coin is increased operational expenses due to longer time between cleaning and better hydrocarbon recovery.
What really saves you the money in the long run is the frequency of reduction of contaminants in addition to energy savings realized with reduced steam consumption in the regenerator boiler. Our liquid/liquid coalescer allows for greater liquid hydrocarbon recovery when compared to flash-drum alone. This also offsets the fuel costs since the recovered oil is now being fed into the boiler. These factors, ultimately cause amine system stability and therefore reliability.