Some 250 professionals and experts in pollution odours gathered in Barcelona at the third conference of the International Water Association (IWA) on Odours, organized by the Group Odournet, Labaqua SA and some other regional organisms and universities.
The event, held from Wednesday, October 8 until Friday, Oct. 9 at the Torre Agbar, was aimed at providing experts, lawmakers and interested participants from utilities and industries, academic institutions and research centers regulators with a forum to share the latest developments and perspectives on the issue of odour and its management to minimize impacts on the population.
Thus, the presentations and sessions of the meeting focused on ten major aims: odour measurements using olfactory methods, evaluation of additives to control odours, odour management, control techniques for treatment and abatement of odorous emissions, characterization of odours using field panels and dispersion modellling, odours at wastewater treatment and sewer systems, waste management operations and industrial processes, sampling; community impacts, VOC and odorant measurement by gas chromatography and electronic nose devices; odour regulation and policy.
The presentations were carried out by experts from public and private institutions linked to the sector. First of all, I would say that the level of the papers at this conference was outstanding and, unlike the last IWA Conference in Cologne, there was just one conference room, which made much easier to follow all the presentations. In any case, I would like to highlight some papers among the set presented at this event. Let see day by day.
In the first group of papers in the morning, the speakers talked about the always interesting subject of the estimation of the uncertainty in the olfactometric measurement. Later, Mr. Ueno presented a comparative study between odour concentration measured with the triangle odour bag method and dynamic olfactometry. The researcher found that odour concentration measured with both methods is comparable, which is a very interesting finding for those laboratories who do not analyze many samples. Machinery for this type of method is simple and the cost of the measure is relatively inexpensive.
After a short pause, a couple of papers about odour emissions of composting facilities were presented and later a group of researchers discussed about methods for odour control with neutralizing and masking agents.
Already in the afternoon of that first day, other very interesting conferences were presented, such as the one of Mr. Van Broeck, who introduced a study about a monetary assessment of odour nuisance as a tool to evaluate cost effectiveness of possible odour reduction.
Other papers focused on odour pollution management from different approaches, such as control plans, in an integrated way or by the use of dispersion modelling, focusing especially in the case of Waste Water/Sewage Treatment Plants (WWTP).
The last session of conferences in this first day introduced a diverse set of control techniques to reduce odour emissions. In this section, some methods to minimize odour emission were presented by means of promising techniques such as ultraviolet photocatalysis in farms, ozonation, a bioreactor or a packed recycling reactor. A paper dealt with a method to control odour emission by means of biofilters and biotowers. This method is rapidly becoming the most popular for odour control.
The next day began with a presentation of Dr. Bilsen. In this paper, she introduced the method of measurement in Flanders with field panels. This prolific author presented other papers later, but in this one, she detailed the method of measurement used in this region of Belgium, believed to be an alternative to the VDI 3940, as it implies a less significant effort in terms of money and time. Meetings are held on a regular basis to regulate and standardize this method.
By means of field panels, buffer distances for farms were validated in another paper. In a later presentation these buffer distances were examined with a dispersion model. The last paper of this session discussed the differences between a Gaussian dispersion model and a Calpuff model as compared with a set of data from field panels.
After a short pause, a series of interesting lectures on management of odours in WWTP's were displayed. The first speaker discussed about air emissions at large municipal wastewater treatment plants for national PRTR register in Finland. Mr. Hobson discussed the pros and cons of covering and ventilation to minimize odours in farms with a technique based on the decay in concentration of added SF6 to measure the rate of leakage from an enclosure with no extraction of air. Later, two presentations focused on the management of odours in WWTP's in Australia and Chile, respectively.
A presentation evaluated the emission and dispersion of hydrogen sulfide from a body of water heavily polluted by developing a dispersion model to characterize the exposure to hydrogen sulfide of a community in the outskirts of Bogota. The last but not least paper in the morning, discussed the results of 10 Years of emission capacity of odours (OEC) measurement. This presentation by Dr. Frechen was very interesting and summarized the latest developments in this field. The OEC is an advanced method to calculate a sort of "emission factor" in liquid phases to characterize odour emission in waste waters. This subject, due to its significance, will be discussed in a later article
The afternoon sessions were grouped into two sets: sampling and impacts on the community. Four very interesting presentations were discussed regarding sampling; I would highlight the paper about models of hydrogen sulphide volatilization from quiescent surfaces were discussed and the one about the design and validation of a wind tunnel system for odour sampling on liquid area sources. Dr. Bokowa, quantified during her presentation the tricky issue of odour emission from fugitive sources. The approach taken by this brilliant researcher was novel and very interesting, as she presented an objective way to quantify fugitive emissions from an activity.
Last, the newest standard of the long-discussed VDI 3880 which regulates the type of sampling to pick for olfactometric measure was presented. The title of this paper mentions the "new VDI 3880", but as of today, sources from this site have found that this norm is not available in the VDI web site.
Session 8 dealt with community impact. In this session, the adverse health effects of odour by means of questionnaires were reviewed. Some case studies about different approaches to deal with community annoyance were also presented.
The final afternoon session of the second day of conferences was interrupted due to a lack of time and some papers were postponed to the next morning. In this section, a set of electronic noses were presented as well as a VOC monitoring by means of electronic devices.
The next morning, Mr. Juarez-Galan, introduced a new universal, portable and cryogenic passive sampler for the time weighted average monitoring of odours and COV's. The sample is collected and maintained under cryogenic conditions, ensuring the stability of volatile compounds before its analysis in the laboratory.
The first session of the last day of this Conference focused on the regulation and legislation on odours in countries like Japan, Netherlands and France. The session was ended with a fascinating presentation in which the first odour map of a whole country was presented. This map was calculated with data from separation distances estimated from validated complaints of the population, drawing a buffer around each activity considered to cause odour annoyance.
Some presentations discussed about methods to control odours by means of bioescrubers at rendering plants, carbonaceous adsorbents/catalysts prepared from sewage sludge, bio-activated sludge packed, gas treatment and evaluation of the impact on biodegradation activity distribution, microbial community structure and resilience capacity in biofilters..
At the end of the conference, the participants that could spare a couple of hours attended two technical visits to Ecoparc2 and the underground WWTP of Besos.
The event was very well organized and we really enjoyed these two days discussing about... odours.