Decarbonisation Technology - February 2025 Issue

Belgium Denmark

33.4

0 0

12.1

8.1 1.9

14.9

0.3

391.2

130.5

11.2

602

9.5

0

0

0

26.1 453

54.5

2.6 20

95

France

85.5

36.9 47.3 41.3

12.1 19.2 12.1

32.5 89.4 34.3

32

0.7 1.6 2.2

427.3 486.4

1,100 2,298

Germany

164.2

89.8 19.7 20.6 30.6

1,367 357.4 666.8 300.2 3,562

32.6 23.3 19.8 19.8

Italy

98.6

266

855 925 702

Netherlands

13

0

0

11

0

193.5 254.7 1,813

UK

43.1

26.7

9.1

17.4

0.2

Total

447.3

152.2

64.6

194.6

207.6

5

129.3

6,577

Table 1 Estimated potential for installation of ORC power plants per selected country and per industrial sector (in MW electricity production )

Organic Rankine Cycle technology for waste heat recovery in the chemical sector Exhaust heat is generated during various stages of chemical processes such as distillation, reaction processes, heat exchange and cooling systems, exhaust gases from combustion processes, and ventilation equipment. This waste heat can be recovered and reused by employing different technologies depending on its characteristics and application. One of the most efficient and economically viable technologies for waste heat recovery is the ORC, which operates effectively within a temperature range of 90°C to 400°C. The ORC system is similar to the traditional Clausius-Rankine cycle, commonly used for electricity generation, but employs organic substances as the working fluid instead of water (steam). These substances have a lower boiling point and higher vapour pressure, making them more suitable for generating electricity from low-temperature heat sources. The organic fluid, which can be a hydrocarbon or a refrigerant, is selected based on its thermodynamic properties that best suit the available heat source. This allows for higher cycle and turbine efficiencies to be achieved. The ORC operates as a closed thermodynamic cycle. Heat from a primary source warms and vaporises the organic fluid, which then expands through a turbine, producing mechanical energy that is converted into electricity. The fluid is then condensed and pressurised to restart the cycle. Using an ORC cycle for waste heat recovery

and rapidly deployable solution that can optimise energy use and enhance the overall sustainability of chemical processes. In one study, the Knowledge Center on Organic Rankine Cycle Technology (KCORC) identifies the waste recovery potential for 1,175 energy-intensive industrial sites across seven EU countries (see Figure 1 ) (KCORC, 2022). Estimates show that more than 50 MW of thermal energy is produced at each site, with 11.7% represented by the chemical industry. For waste heat sources above 250°C, considered more economically attractive, Organic Rankine Cycle (ORC) waste heat recovery plants could allow the installation of around 3.6 GW of electrical power in these industrial sites (see Table 1 ).

Overhead condensers

Hot steam + NCG

Overhead condensers/ subcooler

NCG to ATM

Cooling tower

Pot

Condensate return

Cooling water

Stripping column

CW pump

Figure 2 Traditional layout of chemical plant

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