Overcome upstream challenges with acid gas sweetening

What if we told you that you can have consistent sales gas specification quality for Hydrogen Sulfide and Carbon Dioxide levels? What if you could minimize offgas emissions through effective acid contaminant removal and operating costs from fouling and corrosion control at the same time?

 

We at Pall, aim to solve every gas plant’s major needs:

  1. To achieve or exceed natural gas production quotas via reliable treatment of acid gas.
  2. Maintain process reliability for production consistency and minimization of downtime.

 

Process flow

The process of Acid Gas Sweetening is a bit complex and with every stage, new challenges arise. The process utilizes amines or specialty solvents to remove acid gas such as Hydrogen Sulfide and Carbon Dioxide from sour natural gas to meet the gas quality specifications. The sour gas is contacted with lean amine due to which an acid-base reaction occurs, binding the acid gases to the amine with a weak bond. The rich amine then flows to the regenerator, where heat breaks the weak bond between the amine and gas, releasing the amine gas for re-use. The acid gases exit the top of the regenerator for further treatment while the lean amine is recirculated back to the contactor in a recirculating loop.

 

Production challenges and how we’re solving them

 

  1. The prime challenge faced is foaming and reduced production rates due to hydrocarbon liquid and particulate ingression into the amine loop.
    For this, we recommend effective fluid and solid removal upstream of the contactor to protect the amine loop for improvement of productivity and reliability. KO pots and mesh pads may not always work, which is why we have developed High efficiency SepraSol™ Plus liquid/gas coalescers and Medallion™ HP liquid/gas coalescers which provide 99.999% removal at 0.3 microns per the DOP test and 1 ppb downstream per the modified ANSI/CAGI-400-1999 test procedure
  2. Another challenge due to foaming is process efficiency loss and increased maintenance due to fouling of the contactor, lean-rich exchanger, regenerator and reboiler due to dirty amine.
  3. The best way to overcome this is to reduce the gaps in productivity, reliability and maintenance costs through effective solids control in the amine loop. Solid contaminants in the amine systems are mostly very fine corrosion products that may not be adequately removed by filters that exhibit unloading, media migration, channeling or poor sealing. A range of absolute filter elements is available to reduce suspended solids under 5 ppmw, keep the amine clear or pale yellow to reduce related foaming issues. For enhanced solids control, add filtration to the rich side. Total sour gas worker exposure will typically be lowered due to the reduced system maintenance on the rich side.

 

Also try our PhaseSep® liquid/liquid coalescers, Ultipleat® HF filters, Profile® Coreless filters, Marksman™ filters and Nexis® Filters to enhanced reduction in upsets in downstream Sulphur plant and amine cost control to increase productivity, reliability and gain freedom from slug upsets.