The goal of this work was to give a comprehensive review on biogas production from microalgae biomass. Different process parameters were summarized in tables which could become comprehensive ...compendium of operation conditions of microalgae preparation for biogas production. Further,, the limitations of the process implementation and commercialization (e.g. high costs of implementation and maintenance, low biomass productivity, limited methane yield due to specific structure of microalgae cell wall) were discussed. It was concluded that the microalgae anaerobic digestion should be incorporated with production of other bioproducts such as biodiesel, bioethanol or volatile fatty acids. Such a biorefinery would open possibility to improve both wastewater treatment and generate valuable products from waste streams.
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•The highest total VFAs concentration at RT=5days was achieved at acidic environment.•Alkaline environment was favorable at long RT due to WAS disintegration.•Acetate dominated all of ...the VFAs most likely due to WAS disintegration.•Caproate concentration doubled with prolonging RT from 5 to 15days.
Mixed culture fermentation consists of stable microbial population hence waste could be potentially used as a substrates. The aim of the work was to investigate the impact of pH and retention time on the anaerobic mixed culture fermentation. Trials at different pH (4–12) in unbuffered systems were conducted for 5, 10 and 15days. The highest VFAs concentration was achieved after 15days at pH 10 (0.62g/gVSadded), promising results were also achieved for pH 11 (0.54g/gVSadded). For pH 4 and short retention time propionic acid was the major product instead of acetic acid. For batches run at 15days (besides pH 6) caproic acid presence was noticed whereas at pH 11 occurrence of succinic was quantified. Significant correlation between operational factors and fermentation’s effluents was proved. Throughout changing simple operating parameters one could design process to produce desirable concentration and composition of VFAs.
The article presents how preschool children (aged 3 to 6) develop word-formation competences in the category of nomina agentis (names of agents). The linguistic material was collected with the ...author’s questionnaire. The tasks in this questionnaire were preceded by an example that led the child to the correct word formation scheme. The quantitative and qualitative analysis was created with the division into verbal formants (-acz and -ator) and nominal formants (-arz and -owiec). The analysis included the coding (creation) and decoding (an indication of the motivating word) of derivatives.The research showed how the process of acquiring word formation skills worked in the case of preschool children (aged 3 to 6) of similar social backgrounds. They confirmed that their word-building competence increased linearly, indicated the age at which they start developing these functions and what strategies they used when they were unable to complete the tasks. Among the 1,280 researched utterances, the most common children’s operations were the creation of tranpositional derivatives (e.g. słuchanie), neologisms (e.g. organizacz, organizek, organizant; dokuczaniec, dokucznik; mydłowiec), alternation and adding connectives (e.g. zabaw-l-owiec; kostk-ow-ek). The conclusions reached after the analysis of the material were compared with the hypotheses found in the literature on the subject matter and with the results of other researchers.
In recent years, groundwater contamination caused by dyes has become an important problem. They enter into wastewater as a result of the textile, automotive, or cosmetics industries. For this reason, ...new methods are being sought, which would aid at the removal of dye impurities with high efficiency and also would be relatively cheap. In the presented study synthesized TiO2-ZrO2 (with TiO2:ZrO2 molar ratio of 8:2) and TiO2-ZrO2-SiO2 (with TiO2:ZrO2:SiO2 molar ratio of 8:1:1) oxide materials were used as supports for enzyme immobilization. Effective synthesis of the carriers was confirmed by results of scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), low-temperature nitrogen sorption and Fourier transform infrared spectroscopy (FTIR). The materials achieve high immobilization efficiency of the laccases from Trametes versicolor (83% and 96% for TiO2-ZrO2-laccase and TiO2-ZrO2-SiO2-laccase, respectively). The effect of selected dye concentrations, pH, temperature, and reusability were also tested. The obtained results showed that after removal of textile dyes, such as Alizarin Red S (ARS), Remazol Brilliant Blue R (RBBR), and Reactive Black 5 (RB5), under optimal process conditions, which were pH 5 and 25 °C, from dye solution of 5 mg/L degradation efficiency reached 100%, 91%, and 77%, respectively, suggesting synergistic mechanism of degradation by simultaneous sorption and catalytic action. Finally, reduction of chemical oxygen demand (COD) of the solution after treatment indicated lower mixture toxicity and effective dye degradation.
The recent trend of turning wastewater treatment plants (WWTPs) into energy self-sufficient resource recovery facilities has led to a constant search for solutions that fit into that concept. One of ...them is chemically enhanced primary treatment (CEPT), which provides an opportunity to increase biogas production and to significantly reduce the amount of sludge for final disposal. Laboratory, pilot, and full-scale trials were conducted for the coagulation and sedimentation of primary sludge (PS) with iron sulphate (PIX). Energy and economic balance calculations were conducted based on the obtained results. Experimental trials indicated that CEPT contributed to an increase in biogas production by 21% and to a decrease in sludge volume for final disposal by 12% weight. Furthermore, the application of CEPT may lead to a decreased energy demand for aeration by 8%. The removal of nitrogen in an autotrophic manner in the side stream leads to a further reduction in energy consumption in WWTP (up to 20%). In consequence, the modeling results showed that it would be possible to increase the energy self-sufficiency for WWTP up to 93% if CEPT is applied or even higher (up to 96%) if, additionally, nitrogen removal in the side stream is implemented. It was concluded that CEPT would reduce the operating cost by over 650,000 EUR/year for WWTP at 1,000,000 people equivalent, with a municipal wastewater input of 105,000 m3/d.
•Different substrates will lead to a similar spectrum of products in the MCF process.•In the acidic pH there is higher diversity of volatile fatty acids.•Pre-adjusted alkaline pH is favorable for ...hydrolysis of complex organic matter.
Volatile fatty acids (VFAs) are obtained during chemical routes from non-renewable petrochemicals. Intensive exploitation of oil resources have renewed the idea of VFAs production during biological routes, mainly throughout anaerobic mixed culture fermentation (MCF). We carried out MCF trials at initial acidic (5.0), neutral (7.0, with addition of specific methanogenesis inhibitor) and alkaline (11.0) pH conditions for four different substrates i.e. maize silage, cheese whey, microalgae biomass and glucose. The goal of the study was to investigate the impact of the substrate complexity on the produced VFAs’ quality and quantity. The highest VFAs concentration occurred in neutral pH proceeded by initial alkaline pH (0.83gVFAs/gSCOD for microalgae biomass, 0.78gVFAs/gSCOD for maize silage and 0.71gVFAs/gSCOD for cheese whey, respectively). In the fermentation of glucose, the highest VFAs concentration was achieved in neutral pH. We demonstrated that the alkaline pH was favorable for hydrolysis of complex organic matter (acidification yield over 71% for maize silage fermentation), while the neutral pH was beneficial for the acidogenesis and the overall VFAs production. Our findings showed that it was possible to carry out efficient and stable MCF process without using a large amounts of acid or base for pH adjustment and that the distribution of VFAs only merely depended on the substrate type.
The article presents how preschool children (aged 3 to 6) develop word-formation competences in the category of nomina agentis (names of agents). The linguistic material was collected with the ...author’s questionnaire. The tasks in this questionnaire were preceded by an example that led the child to the correct word formation scheme. The quantitative and qualitative analysis was created with the division into verbal formants (-acz and -ator) and nominal formants (-arz and -owiec). The analysis included the coding (creation) and decoding (an indication of the motivating word) of derivatives.The research showed how the process of acquiring word formation skills worked in the case of preschool children (aged 3 to 6) of similar social backgrounds. They confirmed that their word-building competence increased linearly, indicated the age at which they start developing these functions and what strategies they used when they were unable to complete the tasks. Among the 1,280 researched utterances, the most common children’s operations were the creation of tranpositional derivatives (e.g. słuchanie), neologisms (e.g. organizacz, organizek, organizant; dokuczaniec, dokucznik; mydłowiec), alternation and adding connectives (e.g. zabaw-l-owiec; kostk-ow-ek). The conclusions reached after the analysis of the material were compared with the hypotheses found in the literature on the subject matter and with the results of other researchers.
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•Decreasing the HRT to achieve high OLR reduces the hydrolysis yield.•Shortening of HRT resulted in decreasing of TVFAs produced from cheese whey.•Changes in HRT and OLR did not ...affect production of TVFAs from sludge.•TVFAs composition was impacted by substrate type and microbial biodiversity.•Microbial community from substrate tended to dominate bioreactor.
The objectives of this study were to investigate the effect of hydraulic retention time (HRT) and organic loading rate (OLR) on the volatile fatty acids (VFAs) production from cheese whey and sludge, and to find the relation between total volatile fatty acids (TVFAs) accumulation at different HRT and OLR and the corresponding bacterial community. The highest concentrations of butyrate (5.0 g COD/L), valerate (3.8 g COD/L), caproate (4.2 g COD/L) and heptate (0.8 g COD/L) were obtained from whey fermentation, where proportion of acetate increased with HRT shortening (from 8.3% to 83.5% for HRT of 20 to 1 day, respectively). The highest concentrations of acetate (1.6 g COD/L), propionate (2.9 g COD/L), iso-butyrate (0.8 g COD/L) and iso-valerate (1.8 g COD/L) were obtained from sludge fermentation, where proportion of acids was independent of HRT. Bacterial communities consisted mostly of the phyla Firmicutes, Cloacimonetes, Proteobacteria and uncultured bacterium clones. The bacterial community originating from the substrate was able to adapt to the applied bioreactor conditions and it had an immense impact on the process performance.
Aim of the study: To evaluate the impact of different types of physical activity on life satisfaction, acceptance of illness and adaptation to breast cancer among women after treatment. Material and ...methods : 36 women after treatment of breast cancer with mean age of 59 years (±10.2) were assessed with the satisfaction of life scale, acceptance of illness scale, and Mental Adjustment to Cancer Scale. Physical activity within the group was evaluated. Results : Those women (81% of the group) who participated in Breast Cancer Survivors' Club meetings had higher scores on the AIS (p = 0.01), which means better acceptance of illness and disability. They also had high awareness of the importance of physical activity for recovery after treatment of breast cancer. 94% of the group confirmed that regular physical training was necessary. 82% of them found that they spent more time on training than before the operation. Within the most active subgroup (more than 5 types of activity) higher scores of the fighting spirit item in the Mini-MAC scale (p = 0.019) were observed. Tourist trips (fighting spirit p < 0.01, positive attitude: p = 0.055, constructive style: p < 0.01) and dance (SWLS: p < 0.05, AIS: p < 0.05) had a significant impact on quality of life. Conclusions : Women after treatment of breast cancer had high awareness of the impact of physical activity on recovery. The study subgroup of women who were most active had a better strategy of fighting spirit. Among many types of physical activity, tourist trips and dance were the most important for quality of life. Physical activity seemed to be profitable also for the subgroup outside the Breast Cancer Survivors' Club.
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