A gas sensor array consisting of eight metal oxide semiconductor (MOS) type gas sensors was evaluated for its ability for assessment of the selected wastewater parameters. Municipal wastewater was collected in a wastewater treatment plant (WWTP) in a primary sedimentation tank and was treated in a laboratory-scale sequential batch reactor (SBR). A comparison of the gas sensor array (electronic nose) response to the standard physical-chemical parameters of treated wastewater was performed. To analyze the measurement results, artificial neural networks were used. E-nose—gas sensors array and artificial neural networks proved to be a suitable method for the monitoring of treated wastewater quality. Neural networks used for data validation showed high correlation between the electronic nose readouts and: (I) chemical oxygen demand (COD) (r = 0.988); (II) total suspended solids (TSS) (r = 0.938); (III) turbidity (r = 0.940); (IV) pH (r = 0.554); (V) nitrogen compounds: N-NO₃ (r = 0.958), N-NO₂ (r = 0.869) and N-NH₃ (r = 0.978); (VI) and volatile organic compounds (VOC) (r = 0.987). Good correlation of the abovementioned parameters are observed under stable treatment conditions in a laboratory batch reactor.

The possibility of distinguishing different soil moisture levels by electronic nose (e-nose) was studied. Ten arable soils of various types were investigated. The measurements were performed for air-dry (AD) soils stored for one year, then moistened to field water capacity and finally dried within a period of 180 days. The volatile fingerprints changed during the course of drying. At the end of the drying cycle, the fingerprints were similar to those of the initial AD soils. Principal component analysis (PCA) and artificial neural network (ANN) analysis showed that e-nose results can be used to distinguish soil moisture. It was also shown that different soils can give different e-nose signals at the same moistures.

The time domain reflectometry (TDR) method is commonly used for the measurement of moisture content in soil science. In this study, the method is employed for the measurement of moisture profiles in building materials. The practical applications of the method are presented on an example of water penetration into cellular concrete (aerated autoclaved concrete) samples. The measured results are then used for the determination of moisture diffusivity as a function of moisture content.

The article presents the developed anaerobic-aerobic wastewater treatment technologies. These technologies aimed at removing the organic matter, nitrogen and phosphorus by means of microorganisms immobilized on fibrous carrier surfaces. The results of the laboratory research show the high efficiency of milk wastewater treatment. The following degrees of reduction were achieved for the pollutant indicators: COD -86.7-93 %, total nitrogen - 96.9-97.9 %. Compared to the traditional treatment technologies applied in Ukraine, these values are high. The concentration of organic matters and biomass of not attached bacteria decreased in bioreactor chambers. When the purification process ends, a small amount of excess biomass remains; therefore, its self-oxidation and self-regulation occurs as a result of consumption by the organisms occupying higher levels of trophic chains. The use of anaerobic-aerobic bioreactors system for the treatment of wastewater enables achieving high outflow quality and prevents the suspended substances from slipping. Immobilization of microorganisms on the first stage of the technology prevents the formation of big amount of excessive sludge and removes biomass from the bioreactor, which allows the technology even for the heavily polluted wastewater. In reactors containing immobilized microorganisms, the organic matter compounds used in subsequent reactors for phosphate accumulation are split. The presented biotechnology saves electric energy, provides sufficient quality of treatment, and ensure the compliance of treated wastewater with the effluent standards.

The protists notably ciliates and testate amoebas in the conditions of modernized wastewater treatment plants “Hajdow” (Lublin, Poland) and the nitrogen removal efficiency were studied. Sampling took place every week during the period of August-September 2010. The total of 31 taxa of ciliates and 3 taxa of testate amoebas were identified. Most of the species were registered during the whole research period. Significant abundance reached the following species: Acineria uncinata, Aspidisca cicada, Aspidisca lynceus, Vorticella aquadulcis, Vorticella infusionum, Arcella vulgaris, Euglypha acanthophora and Pyxidicula operculata. In September increase in efficiency of nitrogen removal process was registered. The research shows that the increase of nitrogen reduction efficiency was accompanied by increase of ciliates quantity, mainly due to peritrichid ciliates.