Decarbonisation Technology - November 2022

7

Composition

CO

Mol%

23.4

9

6

3

8

CO 2

Mol%

25

5

Solvent regeneration section

Absorption section

Main BFG header

2

H 2 N 2 0 2

Mol%

4.4

1

4

Feed gas conditioning/ compression section

Mol%

46.9

Mol%

0.3

H 2 S COS

ppmv

20

Figure 3 Overall pilot plant configuration

ppmv

20

DMX pilot design: process configuration The DMX pilot has been designed for a total CO₂ capture capacity of 0.5 T/H. The process description is shown in Figure 3 . The feed gas  from the blast furnace is taken from an existing main process line and sent to a conditioning and compression unit. This unit removes the particles from the feed gas and adjusts the pressure at the DMX absorber inlet (stream  ). The CO₂ is separated from the gas in the absorption section to produce a treated gas  depleted in CO₂. A pure wet CO 2 stream  is produced in the solvent regeneration section. This regeneration section includes the decanter and thermal regenerator. The pilot plant is fitted with all necessary analysers and instrumentation to measure precisely the performances of the capture unit using the DMX Solvent. The treated gas and separated CO 2 are mixed together before being routed back to the main blast furnace gas header  . It also enables recycling of a portion of the treated gas  or CO₂ stream  to the absorber in order to have the possibility to modify (increase or decrease) the CO₂ content at the absorber inlet. The rich solvent  goes from the absorption section to the regeneration section, which in return sends the lean solvent  back to the absorber. Range of operating conditions The composition of the blast furnace gas feeding the demonstration plant is given in Table 2 . The operating conditions can be adjusted at the inlet of the absorber thanks to the compression unit and the recycling lines, as shown in Table 3 , while the operating conditions of the decanter and the regenerator can be adjusted in the pressure ranges shown in Table 4 .

Particles

25 max

mg/Nm 3

Total

Mol%

100

Table 2 Blast furnace composition

Absorber inlet conditions

Pressure

barg

0.2-20

Temperature

ºC

20-40

%CO 2

Mol%

8.0-35.0

Table 3 Absorber range of operating conditions

Regeneration section conditions

Pressure

barg

2.0-5.0

Table 4 Regeneration pressure range

Construction of pilot plant The construction strategy was to prefabricate, under Axens’ responsibility, the main process components in modular form in a yard outside ArcelorMittal’s site and then bring those modules onto the site to minimise site activities. After delivery of the modules to the site at the end of 2021, the unit was connected to the gas and utility networks of the site, pre- commissioned, and successfully started in September 2022. Demonstration plant operation The demonstration plant operation is currently under start-up. A total of 14 months (60 weeks) of operation are planned, excluding the commissioning, start-up, and dismantling steps. The experimental programme has

www.decarbonisationtechnology.com

34

Powered by