Material testing for future commercial post-combustion capture plants–Results of the testing programme conducted at the Niederaussem pilot plant

Abstract

One major part of the cooperation of RWE Power, BASF and Linde, which is aiming at an advanced optimised CO2-scrubbing technology for power plant applications, was the construction and commissioning of the first post-combustion capture pilot plant in Germany at the lignite-fired 1,000 MWel power station Niederaussem. The testing programme executed in the pilot plant is not only focusing on the energy demand for CO2 capture, solvent stability and emissions but also comprises an extensive material testing programme. Steel and plastic samples, tubes and flanges are located in different positions in the plant (pre-scrubber unit, absorber, desorber) to investigate material resistance at a wide range of specific process conditions (temperature, pressure, solvent loading, gas/solvent stream). Coupons made of different grades of stainless steel and plastic were placed in eight different positions. Tubes and flanges made of stainless steel and glass fibre-reinforced plastic were located in five different positions. In addition, a temperature-controlled concrete module equipped with a plastic in-liner was incorporated into the pilot plant. And, finally, different types of gaskets were tested. The testing programme started in mid-2009 with a six-month campaign using 30%-weight MEA as a benchmark solvent. At the beginning of 2010, the testing campaign with the new optimised solvent from BASF was started. This paper summarises the examination methodology based on non-destructive and destructive measurements and discusses some of the results obtained for both testing phases.