Partners:

• ABB Semiconductors AG
  Fabrikstrasse 3, CH-5600, 
  Lenzburg, Switzerland
  person involved:        Mr. Adriaan Welleman, e-mail: adriaan.welleman at ch.abb.com

• De Neef Chemical Recycling 
  N.V.Industriepark 8, B-2220 Heist-Op-Den-Berg, BELGIUM
  person involved         Ir. Peter Kempenaers, e-mail p.kempenaers at deneef.net

• European Commission, DG RTD-G2  
  Rue Montoyer 75, B-1040 Brussels
  contact person:          Dr. Andre Piavaux, e-mail: andre.piavaux at cec.eu.int 

• Institute für Siedlungwasserbau
  Universitaet Stuttgart 
  person involved:        Dr.-Ing. Martin Raiser, e-mail: martin at iswa.uni-stuttgart.de 

• PlasmaAir AG 
  Am Lindenberg 8, 71263 Weil der Stadt
  person involved:        Dr. Bernd Glocker, e-mail: glocker at plasmaair.de  

• Technische Universiteit Eindhoven 
  Faculty of Electrical Engineering 
  contact person:         Dr. Guus Pemen , e-mail: a.j.m.pemen at tue.nl 
                                  www.evt.ele.tue.nl/eps

• Faculty of Physics 
  contact person:         Dr. Eddie van Veldhuizen, e-mail: e.m.v.veldhuizen at tue.nl
                                  www.phys.tue.nl/EPG

Global aim: non-thermal plasma (NTP) technologies

NTPs, which emerged in the last decade, pertain to advanced oxidation technology (AOT) and offer a real promise for the degradation of pollutants in both gas and water streams. Usually they deal with high voltage pulsed discharges (including pulsed corona and spark discharge) or high-energy electron beams, UV and X-ray irradiation, etc., that bring about the production of free electrons, highly-reactive radicals, such as OH, H, O, ozone and ultraviolet (UV) radiation, which destroy the pollutant molecules.

In laboratory experiments, pulsed corona using nanosecond pulses has demonstrated effectiveness against a wide variety of hazardous industrial gaseous and liquid compounds, such as volatile organic compounds (VOCs), chlorofluorocarbons, perfluorinated compounds, etc.

The nanosecond pulse generation technology is based primarily on the capacitive energy storage and closing switches. The simplest example is a capacitor shorted by a spark gap onto a discharge load gap. Although abundant in laboratory use, basic capacitive systems do not allow proper pulse shaping.

Capacitive sources with magnetic compression represent advanced technology. They can be realized with all-solid state switches having microsecond closing times. Magnetic switches (MS) compress a wide microsecond pulse to a desired width.

To be commercialized, nanosecond pulsers must have a lifetime of about 10¹¹ pulses. Capacitive systems with gas discharge closing switches so far have shown limited lifetime (less than 3×10⁹), but new technology developed now has capabilities to reach commercial status. Capacitive pulsers with magnetic switches offer long life, while not being able to generate pulses shorter than 40-50ns without a considerable increase in size and cost.

Innovation

We will investigate a synergetic two-stage technology for remediation of toxic aqueous and gaseous waste streams. The first stage exploits the ability of AOT reactors, based on nanosecond pulsed power supplies (PPS), to crack complex molecules with subsequent biodegradation or catalytic oxidation in a second stage reactor. 

A crucial condition is to be able to construct economically affordable nanosecond PPS. This goal seems presently achievable within the proposed RDT project due to the unique, multinational, European based, expertise brought in by the partners. Soreq and TU/e have established original know-how in PPS. The critical component, e.g. the suitable switches, is the field of expertise of ABB, which is the world leader in this subject. UStutt is a well-known-experienced university in all the environmental aspects involved. This combination makes it feasible to believe that a breakthrough can be achieved by economical application of AOT.

The goals of the present project in the part of PPS are probably best met by the combination of advanced solid-state switching and magnetic compression and/or advanced gas discharge switches. Such approach is cost-effective for medium voltage (several tens of kV) pulse generation at a pulsewidth of about 100ns.

To efficiently transfer the energy from the switch to the load, a pulse forming technology can be employed that is based on the concept of the transmission line transformer. This technology allows accurate impedance matching and voltage matching. In combination with a gas discharge switch, it also incorporates advantages such as a DC return path for the HV terminal, open and short circuit durability and high efficiency.

This basic idea can be implemented in various scenarios that are to be tested in this project.

Results

Papers:

L.R. Grabowski, E.M. van Veldhuizen, W.R. Rutgers, "Removal of Phenol from Water: A Comparison of Energization Methods",  J. Adv. Oxid. Technol. 8(2005)142-149.

L.R. Grabowski, E.M. van Veldhuizen, A.J.M. Pemen, W.R. Rutgers, “Corona Above Water Reactor for Systematic Study of Aqueous Phenol Degradation”, Plasma Chem. Plasma Procs.26(2006)3-17

L.R. Grabowski, T.M.P. Briels, E.M. van Veldhuizen, A.J.M. Pemen, "Streamers in pulsed positive corona: low and high current regimes", XVIIth Int. Conf. on Phenomena in Ionised Gases, Veldhoven, the Netherlands, July 2005, paper Grabowski-ICPIG2005.pdf

A. Pokryvailo , M. Wolf , Y. Yankelevich , E. Abramzon , A. Welleman, "A Compact High-Power Pulsed Corona Source for Treatment of Pollutants in Heterogeneous Media", Soreq-ICPIG2005

L.R. Grabowski, "", PhD thesis, Technische Universiteit Eindhoven, april 2006.

A. Pokryvailo , M. Wolf , Y. Yankelevich , A. Welleman, L.R. Grabowski, E.M. van Veldhuizen, W.R. Rutgers, P. Kempenaars, "" review paper on the whole project, to appear in IEEE Tr. Plasma Sci. okt. 2006

Photos:

-Prototype semiconductor switch ABB

-Test semiconductor switch at Soreq

-Gas cleaning reactor built by Soreq

-Water cleaning test setup at TUE

-Corona discharge in water cleaning reactor TUE