BASF is the licensee of the MDEA plants, as well as for two other gas scrubbing plants, the ammonia plants and the synthesis gas plants. Through successful collaboration, the LiquiSonic® System is recommended for MDEA concentration measurement by BASF AG Ludwigshafen.
Sound velocity measurement in MDEA
Application
In the absorber, the natural gas is passed countercurrently through the washing liquid, which becomes enriched with the interfering components. At the top end of the absorber, the purified natural gas exits. The
H2S and CO2 contaminated MDEA (rich amine) is transferred to the so-called stripper after washing. In the stripping process, the washing solution is heated, causing the sour gases to desorb. The regenerated MDEA (lean amine) is then cooled, filtered, and returned to absorption.
The LiquiSonic measurement system® 30 enables precise analysis of the regenerated MDEA concentration as well as permanent data collection. Through the inline LiquiSonic® sensors the amine wash is monitored around the clock. This allows for immediate response to fluctuating MDEA concentrations and increases the efficiency of absorption.
Installation
The LiquiSonic® sensors are installed in the DN50 pipeline from the stripper to the absorber after the amine cooler and filter, and additionally in the MDEA tank.
Concentration range: 20 to 45 m%
Temperature range: 30 to 65 °C
Customer benefits
Continuous measurement of the MDEA concentration using inline sensors eliminates manual sampling. This results in savings on material and labor costs, as well as increased plant safety.
- Time required: 1 h per day
Through concentration measurement using LiquiSonic® the purity of the regenerated MDEA washing solution is ensured for optimal absorption efficiency. This avoids overdosing of the MDEA washing liquid.
The amine wash is a chemical process for the separation of CO2, H2S and other acid gases from natural gas. A slightly alkaline aqueous solution of amines (mostly tertiary amines) is used, which reversibly chemically absorbs the acidic gases. Due to its high selectivity to H2S and CO2 , the tertiary methyldiethanolamine (MDEA) is used as an absorbent. The aim of the gas scrubbing is to prepare the sour natural gas for further transport according to the pipeline requirements, as otherwise corrosion damage may occur.
