The 4th International Biotechniques-Conference took place at the Palexco–Conference and Exhibition Centre of La Coruña (Spain), on 12–14 October 2011. As with previous conferences in this series, the event was a great success and brought together people from many different countries from Europe, Asia, Australia, North Africa, the Middle East, and both North and South America. This Special Issue is a compilation of only a few selected papers presented at the conference.
The conference focused mainly on the role of biotechnology in minimizing and solving environmental problems such as air pollution. At least two different biological approaches can be considered for reducing air pollution. On one side, polluted air treatment can be carried out through the use of specific bioreactors. On the other side, emissions can be reduced through the development of cleaner (bio)fuels, which can be obtained from more environmental-friendly sources than fossil fuels, and with a reduced impact on the environment.
Since the first conventional biofilter was built for odour treatment, several other different bioreactors have been developed for air pollution control. They include biotrickling filters, bioscrubbers, membrane bioreactors, two-liquid phase systems and other innovative bioreactors such as planted-biofilters, several of which have been described at the conference.1–6 Although such bioprocesses were originally mainly used for reducing odour nuisance at, for example, wastewater treatment plants and composting facilities, they are nowadays also being used for the treatment of industrial waste gases and for the removal of a very wide range of organic and inorganic compounds. Many different examples were shown during the event in La Coruña.3, 7–13 Studies aimed at testing efficient mathematical reactor models, developing molecular biology techniques or solving potential problems during long-term bioreactors operation have also been presented at the conference.7, 14–16
Another approach that allows reducing environmental pollution, among others air pollution, is the development of cleaner (bio)fuels. Biofuels are more environmental-friendly than conventional fuels, as they can be obtained from wastes or renewable biomass.17 Biofuels have been shown to give rise to reduced net emissions of greenhouse gases (GHG), such as CO2, compared to fossil fuels.18 It is even claimed that some biofuels are carbon neutral when the biomass grown for biofuels production consumes a similar amount of carbon dioxide to that emitted to the atmosphere during biofuels combustion. This is indeed partly true, although other factors should also be taken into account, such as the energy input needed for biomass production or nitrous oxide (another GHG) emissions resulting from the use of fertilizers for crop production. An interesting recent approach consists of converting waste gases into fuels.19 Some examples were presented at the conference, such as the conversion of CO-containing gases into ethanol,20 or the conversion of a greenhouse gas into another greenhouse gas, but with potential as a biofuel, such as methane.21 One should remember that it is not always cost-effective to try to recover methane or biogas obtained from waste; but in such a case, it can here again be eliminated in gas-phase bioreactors.22 It is worth mentioning that the use of some gas-phase bioreactors, suitable for waste gas treatment, can also be suitable for biofuels upgrading. In that respect, some presentations at the conference focussed on the efficient removal of corrosive hydrogen sulphide from biogas in bioreactors.23
We look forward to the next event and trust the 2013 Biotechniques-Conference, to be held in France, will again be a great success and a good opportunity to share information on recent advances in the use of bioprocesses and bioenergy for reducing environmental pollution.