Eaton’s ClearAmine™ automatic self-cleaning system helps ensure a continuous supply of pure amine for the removal of acid gas (H2S and CO2).
Processing toxic, corrosive and explosive chemicals at high temperatures and pressures creates a uniquely hostile and dangerous environment. The fact that it is safely done every day in refineries around the world is a tribute to the skill and expertise of the engineers who design and operate them, but there is always room for improvement. Modern filtration technologies can make a significant contribution to both operator safety and overall productivity while reducing a refinery’s carbon footprint and environmental impact.
That is not conjecture. The safety enhancement and other benefits of modern, “clean-in-place” filtration systems have been proven in hundreds of refineries. The technology is widely used in catalyst protection and coking applications and is now being applied in a growing number of “amine units.”
An amine unit is used to remove hydrogen sulfide (H2S) and carbon dioxide (CO2) contained in many crude oil feedstocks prior to refining. The process uses an amine, typically diethanolamine, monoethanolamine or methyldiethanolamine (DEA, MEA, MDEA) to remove H2S and CO2 from hydrocarbon gases.
As the amine circulates through the process, it picks up contaminants including pipe scale, rust, iron sulfide, sand and a variety of other solids. These foul system components include flash drums, heat exchangers, strippers, re-boilers and carbon filters. The amines also attract hydrocarbons, a major cause of system foaming, which reduces process efficiency.
Pipe scale, rust, iron sulfide, sand and other solids build-up in closed-loop amine systems fouling flash drums, heat exchangers,
strippers, re-boilers, and carbon filters. They also attract hydrocarbons, which cause system foaming. Eaton’s Clear-
Amine™ system provides an efficient method of removing harmful solids to protect and extend equipment life, and maximize
amine systems’ effectiveness.
The process is continuous, with the “rich” contaminant-bearing amine being regenerated and reused as “lean” amine. The most common amine filtration solution today uses cartridge-type filters to remove contaminants from the lean amine stream after regeneration. This ultimately exposes everything upstream of the regenerator to a full load of contaminants.
Rich-side filtration is a better solution in terms of protecting the equipment, but opening a cartridge-type filter system unnecessarily exposes workers to dangerous and potentially explosive H2S and other hazards when changing cartridges. The cartridges themselves also represent an inventory expense and must be disposed of as hazardous waste creating both cost and environmental impact issues.
Since clean-in-place filter systems minimize or eliminate the need for operators to open the filter system during operation, the safety impact is obvious. These systems typically use a backflush and purge cycle with a backpressure-sensing control. The filters are installed both as single units with a bypass and as multiple banks to provide continuous protection.
The enhanced operator safety provided by a clean-in-place system makes it much more practical than cartridges to filter the rich amine side of the process. This can extend the life of costly system components while dramatically reducing operating and maintenance costs.
These are not the only benefits. A clean-in-place filtration system also can significantly reduce a refinery’s environmental impact and carbon footprint. Compared to the commonly used disposable media systems, an automated clean-in-place system dramatically reduces the number of bags and/or cartridges that must be purchased, inventoried, handled and eventually disposed.
Removing contaminated bags and/or cartridges from the waste stream reduces the gaseous emissions associated with their decomposition as well as the associated hazardous waste landfill fees. Over a ten-year period, these savings can add up to nearly a 60 percent cost reduction compared to today’s commonly used disposable media systems.
Making the refineries that fuel our modern, global society more productive, more environmentally sustainable and above all safer than ever before is a huge challenge. Fortunately, it is one the filtration industry is well prepared to help their customers meet.