Wednesday, January 21, 2009

Tytronic Sentinel Amine Analyzer


APPLICATION

The Tytronics Sentinel Amine Analyzer is an online process analyzer that is capable of measuring acid gas loading in both rich and lean amines. It can be used to measure H2S content in amines (as sulphide), total acid gas loading (both CO2 and H2S), as well as amine strength. Multiple analyzers may be required depending on the number of analyte measurements, concentration range and distance between sampling points.

PRINCIPLE OF OPERATION

The Sentinel analyzer is a potentiometric titrator which uses an electrode to monitor changes in ion activity in the solution during the addition of a titrant, referred to as titration. An equivalence point or endpoint is reached when the ions in solution have completely reacted or complexed with the ions supplied through the titrant addition (there is no further ion activity). At the equivalence point the concentration and volume of the titrant solution added to the reaction cell determines the equivalent concentration corresponding to the analyte of interest.

It is this titration technique that is used to determine three main analytes of interest in the amine samples. These are as follows:

  1. Amine Strength Determination - To know the exact loading of the amine, it is necessary to know the amine strength, a measure of the percentage by weight of an amine solution that is amine. This measurement is carried out using a color titration of lean amine.

  2. Total Acid Gas Loading - The acid gas loading is determined by titration of the lean or loaded amine with a base, with the endpoint determined using pH measurement.

  3. H2S loading - H2S loading is determined by potentiometric titration of the lean or loaded amine using a sulphide selective ISE.

FEATURES AND BENEFITS

  • If one of each amine analyzer variant is installed, the analog outputs from each unit can be combined in a data collection system to get a complete set of measurements for each stream - amine strength, H2S concentration, and CO2 concentration.

  • Regenerate amine only when necessary based on loading, reducing energy costs for regeneration and extending amine life.

  • Calibration based on lab results - monthly laboratory measurements of the parameters of interest are used to calibrate the analyzer

  • Reduced regenerator steam consumption by operating with residual H2S that ensures specification sweet gas instead of over-stripping to provide a safety margin

  • Reduced amine loss through carry-over

  • Reduced plant corrosion