Absorption and distillation are important separation technologies in the chemical industry but they require a lot of energy. TNO is working with industrial end-users, equipment manufacturers and technology suppliers to develop and scale up techniques to make the processes more efficient and energy efficient. The first successes have been achieved in the E-Champ project.
TNO is collaborating in the E-Champ project with end-user Dow Benelux, equipment manufacturer Vahterus of Finland and its Dutch supplier Wijbenga, system integrator TechnipFMC and R&D company SUSTER. “After successful tests in the lab at TNO, we were brought in to test the technology on a larger scale under real conditions,” says SUSTER director Bert Heesink.
“We have facilities available to test CO2 absorption technologies on a pilot scale. TNO's lab results formed the basis for this. We installed and tested the heat exchanger supplied by Wijbenga in our pilot setup, after it had been made suitable for CO2 absorption with a liquid solvent by Vahterus. In this way, we showed that it is possible to capture the absorption heat immediately after release and increase the CO2 absorption capacity of the unit. Which results in cost savings and reduced environmental impact.”
Cost savings
A new feature of the technology is the simultaneous absorption and cooling. These two functions are now united in one device for the first time. Common practice is to use a reactor and a cooler (or heater) as separate units in an industrial process. That means not only a greater investment but also less efficiency.
“The integrated cooling provides companies with substantial cost savings.”
TNO expert Yvonne van Delft: “The integrated cooling can save as much as fifteen percent on circulation speed and another seven percent when reboiling to boil off the absorbed CO2. This provides a company with substantial cost savings. The amounts involved are substantial.”
The tested module, also called plate-&-shell heat exchanger, can be purchased new, but can also be built into existing plants. Compared to traditional combinations of reactors and heat exchangers, cooling now occurs much faster and more intensely.
With better cooling, less energy is used per ton of CO2 removed, and with this, the CO2 emissions from the removal process itself are also lower. Removing CO2 from industrial gas streams is quite pricey, which is why it is still not done on a large scale. The new technology is not necessarily for this purpose, but it makes a welcome contribution.
More applications
“This way the knife cuts both ways,” says Yvonne van Delft. “You can also use a unit like this in the pharmaceutical industry, for example. More applications are conceivable where you want to cool directly during the heating of liquids in an industrial process, during absorption or during a reaction. Sectors such as the oil and gas industry and the chemical industry are faced with the task of emitting less CO2. With this technique, you need less energy and CO2 emissions go down.”
“You can apply this principle to any chemical process that requires the removal or addition of heat.”
Bert Heesink: “You can apply this principle to any chemical process where heat needs to be removed or supplied. In the new module, you can add or remove heat at the source according to the need. It may be desirable to remove heat to prevent a chemical reaction from reaching chemical equilibrium in order to achieve a higher conversion rate. In pharma, cooling allows you to prevent your product from getting too hot during the process and breaking down.”
Further improving the design
The E-champ project is one of many examples of TNO working as a knowledge partner with industrial end-users and the manufacturing industry on technological innovations. The measurements made during the tests at SUSTER are now being incorporated by TechnipFMC into their models.
This should lead to an improved design of the module for subsequent testing in an industrial pilot. Ultimately, this should yield a device that can be used for both absorption and distillation processes. With this technology, the Netherlands is among the international vanguard.