Environmental biotechnology: the ongoing quest

Journal of Biotechnology 98 (2002) 113 Á/123 www.elsevier.com/locate/jbiotec

Environmental biotechnology: the ongoing quest
R. Grommen, W. Verstraete *
Laboratory of Microbial Ecology and Technology (LabMET), Ghent University, Coupure Links 653, B-9000 Ghent, Belgium Received 16 July 2001; accepted 16 January 2002

Abstract Environmental biotechnology, until now, has primarily focused onthe development of technologies to treat aqueous, solid and gaseous wastes. At present, the basic knowledge on how biotechnology can handle these wastes has been acquired and the focus is now on the implementation of these processes as ‘best available technology not entailing excessive costs’ (BATNEEC) in the framework of strict and transparent environmental legislation. New environmentalchallenges continue to evolve, as it becomes clear that waste streams should be tackled in an overall holistic way. New technologies to reach this goal are currently under development. Novel aspects with respect to the domain of water treatment are, for example, the biomembrane reactor technology and the newly discovered processes to remove nitrogen by means of anaerobic ammonium oxidation. Also, mostchallenging is the continuing strive for re-use of treated wastewater. Indeed, water shortage is emerging in an increasing number of countries all over the world and necessitates the short cycling of water. Finally, biotechnology has a key role to play in the novel approaches to design wastewater treatment based on decentralised sanitation and reuse (DESAR). Solid waste is a major challenge worldwide.The implementation of anaerobic digestion to treat biowastes has become a grown-up technology. New approaches in which biotechnological processes are linked to physical processes, such as plasma technology, certainly deserve special attention for the coming decades. Soil and sediment clean up by means of biostimulation/remediation/ augmentation is now well established. Certainly, a number ofprospects need to be further explored, such as the use of special energy sources to stimulate in situ the microbial community and the seeding of knowledge to the in situ community by means of horizontal gene transfer mechanisms. A number of waste gases can be handled by biofilter systems. Biological treatment of wastegases is also evolving, inasmuch as that besides conventional chemical pollutants,now also highly problematic chemicals (even dioxins) can be dealt with through proper biotechnological approaches. A remarkable new potential is the use of well designed probiotics to upgrade aquaculture and together with conventional biological water treatment processes, to guarantee the overall water quality of this domain of food production. # 2002 Elsevier Science B.V. All rights reserved.Keywords: Biotechnology; Wastewater; Solid waste; Aquaculture

1. Framework for environmental technology and biotechnology
* Corresponding author. Tel.: '/32-9-264-5976; fax: '/32-9264-6248 E-mail address: willy.verstraete@rug.ac.be (W. Verstraete).

Environmental issues have been on the agenda for several decades now and it might therefore

0168-1656/02/$ - see front matter # 2002 ElsevierScience B.V. All rights reserved. PII: S 0 1 6 8 - 1 6 5 6 ( 0 2 ) 0 0 0 9 0 - 1

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R. Grommen, W. Verstraete / Journal of Biotechnology 98 (2002) 113 Á/123

seem that the hype of environmental technology is over. However, it cannot be denied that several environmental challenges continue to exist and their magnitude even increases. For instance, the spread of unwanted biological propagulesis of major concern in Europe. The costs of remediating the spread of a prion, such as BSE or a virus, such as Foot and Mouth disease, costs the EU staggering amounts of money; for example, the direct economic impact of the BSE crises is estimated to cost each inhabitant some 13 Euro per year. The same applies to unwanted chemicals, recently referred to as POPs, i.e. persistent organic...