Monitoring and efﬁciency assessment of bioﬁlter air deodorization
using electronic nose prototype
Received: 30 June 2017 / Accepted: 4 October 2017 / Published online: 9 October 2017
Ó Institute of Chemistry, Slovak Academy of Sciences 2017
Abstract Bioﬁltration is one of the techniques used to
reduce odorants in the air. It is based on the aerobic
degradation of pollutants by microorganisms located in the
ﬁlter bed. The research presents the possibility of using the
electronic nose prototype for monitoring and efﬁciency
assessment of air bioﬁltration. The study was conducted
using model gas mixtures containing representatives of
three groups of chemical compounds: n-hexane (alkanes),
acetone (ketones) and toluene (aromatic hydrocarbons).
Based on the proposed linear models it has been shown that
the determination of concentrations of these substances in
the ternary mixture is possible at relatively low concen-
trations. It was also shown that the used ﬁlter medium (pine
bark) had the highest removal efﬁciency of acetone.
Keywords Odorants Á Bioﬁltration Á Electronic nose Á
Metal oxide sensors Á Odours concentration Á GC-FID
In recent years, many areas of human activity, especially
waste disposal and waste water treatment processes are the
source of odour nuisance. It is caused mainly by inorganic
gases (hydrogen sulphide and ammonia) and volatile
organic compounds (VOCs), which are formed during the
biodegradation of organic compounds (Lehtinen and Vei-
janen 2011; Lewkowska et al. 2016).
There are four main groups of techniques used to reduce
odorants in the air: combustion, adsorption, absorption and
biological methods. Bioﬁltration is one of the biological
puriﬁcation methods (Leson and Winer 1991). Due to the
low operating costs and its ability to treat large volumes of
puriﬁed gas, it is considered to be the best deodorization
method for low-concentrated emissions (Muldiar et al.
2010). Bioﬁltration is based on the aerobic degradation of
pollutants by microorganisms located in the ﬁlter bed
wka et al. 2013). At the contact of the odorants with the
ﬁrst layer of bed covered with bioﬁlm, they are absorbed
and then decomposed by microorganisms (Delhome
Heitz 2005). This process goes deeper into the bed and
when the gases reach the end of the bioﬁlter, most of the
pollutants are already degraded. Several types of bioﬁlter
media are used: coated ceramic particles, compost, peat,
soil or wood bark (Barbusinski et al. 2017). Low molecular
weight and water-soluble compounds, such as hydrogen
sulphide, ammonia, alcohols, aldehydes and ketones, are
the most susceptible to bioﬁltration (Burgess et al. 2001).
The efﬁciency of removal of selected groups of chemicals
using bioﬁltration is shown in Table 1.
Several analytical methods can be used for the deter-
mination of gas concentrations in the bioﬁltration process.
The most popular is gas chromatography coupled with
different types of detectors: olfactometry (O), mass spec-
trometry (MS) or ﬂame ionization detector (FID) (Gutie
rez et al. 2015). From a quantitative and qualitative point of
view, gas chromatography is the best solution. However,
the need to buy expensive equipment and provide appro-
priate working conditions (high vacuum or hydrogen
availability) often makes use of GC uneconomical.
& Bartosz Szulczyn
Department of Chemical and Process Engineering, Faculty of
sk University of Technology, 11/12
Narutowicza Street, 80-233 Gdan
Department of Analytical Chemistry, Faculty of Chemistry,
sk University of Technology, 11/12 Narutowicza Street,
Chem. Pap. (2018) 72:527–532