260 240 220 200 180 160 140 120 100
Steam boiler + ETS
MVR
QHT
80 60 40 20 0
06/12/2020
07/03/2021
06/06/2021
05/09/2021
05/12/2021
06/03/2022 05/06/2022 04/09/2022
04/12/2022
Figure 3 Historical marginal steam cost for EU industrial consumer in EUR/ton steam for different methods of steam generation (MVR = mechanical vapour recompression)
variable pricing and CO₂ credits or taxes. Figure 3 displays the marginal steam cost for an industrial facility in Europe based on Dutch TTF natural gas prices and EU ETS prices. The yellow curve gives the business-as-usual case where steam is produced by combustion of natural gas, and EU ETS credits are purchased to cover emissions. The blue and red curves display the steam cost when using a mechanical vapour re-compressor (MVR) and a QHT. The very low total operational cost of a QHT means a plant owner can hedge their steam price during the full lifecycle of the installation, being the industry standard of at least 20 years long. Commercial-scale references Pioneering references of the QHT technology are situ- ated in the chemical industry (such as SABIC, Kuraray, and Borealis). Operational examples have confirmed the unique temperature lift and low electrical consumption, as previously explained. In addition, new significant features
appeared, such as the intrinsic flexibility of the chemistry to production fluctuations. One such example is shown in Figure 4 , which displays the actual operating pressure of the customer’s steam header in red. In blue, one can see the mass flow of steam produced by the QHT and released into the header. At 9:35 pm on April 13th, the overall header pressure suddenly decreases from 4.1 to 3.5 bar due to an upset in demand by one big steam consumer. The QHT exports steam via a pressure control valve on the custom- er’s header and automatically increases exports from 800 to 1,350 kg/h to buffer the falling header pressure. When the header pressure was restored, the QHT unit automat- ically returned to nominal condition. The time span of the action was +/-25 minutes, and no operator involvement was needed to control the QHT behaviour. Refinery applications As a very flexible energy efficiency technology, applications
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7:40 PM 13/4/2022
8:20 PM 13/4/2022
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9:20 PM 13/4/2022
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11:20 PM 13/4/2022
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Figure 4 Operational example of the QHT unit flexibly buffering the customer’s steam header in case of a calamity
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PTQ Q3 2023
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