The plant is specially designed for solvent testing in post combustion and can be used for

• Testing of new potential amines
• Testing of degradation in long-term running experiments
• It is possible to add traces of other gases into the flue gas
• Water wash experiments
• Testing of new technology related to emission control

SINTEF Tiller Pilot Plant

The pilot plant was commissioned in 2010 and has been upgraded several times later. It is located inside a building at the SINTEF site at Tiller. A propane burner (380 kW) is providing heat to the buildings and flue gas to the plant. As an upgrade in 2016, the plant has been supplied with a coal and biomass burner with extra flue gas pre-treatment equipment. The columns diameters in the plant have been dimensioned according to the amount of flue gas available and are quite small. However, the design philosophy has been to otherwise design the plant as similar as possible to a fullscale post combustion plant. The gas rate (m/s), the liquid load (m3/h*m2), the packing material and the total packing heights are similar, such that the conditions for mass and heat transfer from gas to liquid and reaction rates will be very similar as in an industrial sized plant. Thus, upscaling the result from this plant is very straight forward.

The pilot plant consists of three main parts: The flue gas pre-treatment, the CO2 absorption part, and the solvent regeneration part. The pre-treatment part is used for SO2 removal and setting the flue gas flow rate, the temperature, the moisture, and the CO2 concentration to desired values according to the experimental plan. The exhaust gas is first diluted with air and/or supplied with CO2 from the stripper to get the desired CO2 concentration. It then goes through a direct contact cooler (DCC) to cool down the gas and get a well-defined humidity. If using flue gas from the coal burner SO2 is removed with NaOH and pH control. The DCC is a 26 cm ID column with 2.5 m Mellapak 2X structured packing where cooled water is circulated. Downstream the DCC is a high-capacity fan. A final adjustment of the gas temperature is obtained by a heat exchanger before the absorber.

The absorption column has 20 cm ID and is equipped with 19.5 m structured Mellapak 2X packing divided into four sections. Liquid distributor and redistributor sections (in-house SINTEF design) are installed between each section, which facilitate sampling of both gas and liquid between each section. In the upper part of the column (above the 4th absorption section) two water wash sections with structured Mellapak 2X packing are used to remove amine vapour in the flue gas. Two extra water wash sections are implemented as an option. The last wash section is equipped with pH-control and may be used as an acid wash. Demisters are placed above the upper lean solvent distributor and above the upper water wash distributor and acid wash distributor to remove entrained droplets. Inter-cooling systems have been installed between the sections to lower the solvent temperature in the absorber. The column is instrumented with temperature sensors every meter, and pressure sensors below each packed column section and above the upper water wash section. Each of these sections is designed for representative sampling of gas and liquid.

The solvent regeneration system consists of electrical heated reboiler (60 kW), desorption column and two condensers to separate stripped CO2 and water/amine vapour. Recovered CO2 will be discharged to the atmosphere or recirculated to the feed gas system upstream of the DCC in order to increase the CO2-concentration. It might also be used in the CO2 compression and liquefaction unit (CCLU) completed in 2022 where impurities in the CO2 product might be analysed. The stripper column has an ID of 16.2 cm, and a total packing height of 13.6 m structured Mellapak 2X packing consisting of three sections with solvent distribution/redistribution between each section. It is possible to add heat to the liquid before the redistribution. The stripper column is equipped with temperature measurement every meter and pressure measurement below each section and above the upper section. The stripper column and the reboiler are equipped with a heat tracing system providing minimal heat loss to the surroundings. The upper part of the stripper column has two water wash sections similar to the water wash in the absorber. Demisters are placed above the upper (rich) solvent distributor and above the upper water distributor to remove entrained droplets.

The desorber system can operate up to 4-5 bars. However, an optional medium pressure desorber has been constructed in 2022 that can operate up to 20 bars. This desorber column has an ID of 10 cm, and a total packing height of 15 m structured Mellapak 2X packing and two water wash sections. The reboiler is heated by steam and the warm parts of the unit is like the original desorber heat traced.

SINTEF/NTNU Lab Pilot

The pilot was built in 1998 and is located at the university campus. It was upgraded in 2004 and 2013. The gas treating capacity is approximately 150 m3/h. The absorber has an ID of 0.15 m and a packing height of 4.23 m whereas for the stripper the height and diameter are 3.57 m and 0.10 m, respectively. Both columns have Sulzer BX packing. The pilot is fully automated with continuous logging of:

• Liquid and gas flows
• Temperature profiles in the packed columns (7 probes in the absorber and 5 probes in the stripper)
• CO2 concentrations in and out the absorber
• Reboiler heat duty
• Temperatures and pressures in the pipes

The absorber is connected to a water wash section with height of 2.1 m and ID of 0.15 m (packing type Sulzer 250Y). Total amount of liquid solution needed for operation is ~180 l. The pilot is operated continuously (24 hours) and no operator is needed present in the evenings/nights.

Both plants are very well instrumented and controlled such that steady-state conditions in the column are easily obtained. At Tiller the desorbers are heat-traced keeping close to adiabatic conditions and the burners give a constant and reliable source of gas. The lab pilot operates with synthetic flue gas.

Data management systems have been made such that the results are easily processed and presented. Experienced and skilled technicians/scientists give the necessary support to get the best out of the campaign program. Both facilities are very flexible with easy access to all parts of the plant. Modifications and additional instrumentation of the plant may be done inexpensively.

SINTEF have long experience in gas sampling and analysing. Skilled scientists and technicians are available to assist visiting partners. A desk with internet access will be available during the stay. The analysis facility is very good including advanced analysis of degradation products due to a very well-equipped analytical laboratory.

Operational constraints

• Both pilots are located inside buildings. The solvent to be tested must be approved by SINTEF/NTNU to ensure safe working environments for all. If needed the working environment will be monitored by manual gas sampling during the campaign.
• Local HSE rules must be followed.
• The solvent must pass corrosion tests (either satisfactory corrosion data for solvent is provided beforehand or SINTEF will run their own corrosion tests)
• Main operator from either NTNU/SINTEF will be needed to ensure safe operation of the pilot.

SINTEF Industry has implemented and maintains a quality management system that fulfils the requirements of the standard NS-EN ISO 9001:2008 within research and development in materials technology, advanced materials and nanotechnology, applied chemistry and biotechnology, oil and gas, and green energy and process industry.