ECN Energy Efficiency in Industry

P.O. Box 1, 1755 ZG Petten

Westerduinweg 3, Petten, The Netherlands

Tel : +31 224 56 82 40

Fax : +31 224 56 86 15

Contact: Arend de Groot

a.degroot@ecn.nl

We will continue until energy is clean and available to all. www.ecn.nl

Process intensificationBackgroundEnergy research Centre of the Netherlands at Petten is an independent market-oriented organisation forresearch, development, consultancy and knowledge transfer in energy-related fields. ECN developssustainable technologies and is engaged in work on solar, wind and bio-mass energy, fossil fuels, energyefficiency and policy studies.

In recent decades there has been a significant increase in the energy efficiency of the process industry byoptimisation of unit operations. In many cases the limits of what can be done on a unit-operation scalehave been reached. To maintain the trend of increasing energy efficiency, it will be necessary to concentratethe various physical steps and chemical reactions into a single process step that makes only the desiredproduct. For this purpose, new technologies are needed that fundamentally and radically change theindustrial processes. This combination of unit operations is called process intensification.

• Reaction-separation: Membrane reactors,reactive distillation.

• Reaction-heat exchange: HEX-reactor.• Separation-heat exchange: Dephlegmators or

heat integrated distillation.• Reaction-separation-heat exchange:

Isothermal membrane reactor.

What is process intensification?In many chemical production processes, reactionsare limited by physics. Reaction rates are oftenreduced by slow mass transfer of reactants to thereaction, bad heat supply to or removal from thereaction and build-up of products. The design ofthe unit, rather than the chemistry itself, is thelimitation.

Process intensification aims at designing reactorsin such a way that these barriers become (ordersof magnitude) smaller. More compact units, lowerinvestment cost, higher yields and reduced energycost result from this. One of the most powerfulprocess intensification methods is combiningtwo or more classical units into one hybrid unit.

General examplesIn the figure examples are given for three unitoperations that are often used in the chemicalindustry. Examples of combinations are:

Example of membrane reactor flowsheet for hydrogen production and CO2 emission reduction.

Examples of a combination of unit operations inprocess intensification.

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R&D programme at ECN• Membrane reactors in which the reaction is

combined with separation of the reactionproduct from the reaction zone. Advantagescan be very high when this is used for shiftingthe equilibrium of reactions such as dehydro-genation, steam reforming, esterificationreactions, or ammonia synthesis.

ECN’s patented plate-fin heat exchanger conceptthat can be used in a Heat Integrated DistillationColumn (HIDIC).

Show model of a membrane reactor for hydrogenseparation during steam reforming.

• Membrane contactors, where reactants are fedin a controlled way to a reaction, leading to ahigher quality of the desired product withlower amounts of by-products. Application ofmembrane contactors is foreseen in the fieldof partial oxidation reactions.

• Membrane emulsification. High-valueemulsions can be made via a porous structurein which very well controlled local and highlyintensified shear rates can be obtained, leadingto a process with much lower energy use andmore homogeneous emulsions than the con-ventional high-speed high-pressure mixers.

Clients, co-operation partners and financiers areoriginating from major process industries, smalland medium enterprises, European Union, nationaland local governments, universities and researchinstitutes.

Interested in an energetic and challengingtechnology venture with us:

Call ECN!

Examples of emulsion droplet formation via aporous membrane.

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