Revista Ambiente & Água - An Interdisciplinary Journal of Applied Science

1-10

Authors: Claudio Eduardo Scherer ; Marcio Barreto-Rodrigues

This study characterized and evaluated the potential of a combination of treatment strategies for the removal of phenolic compounds, color, and ecotoxicity of an effluent generated by a laminated wood industry. The characterization of a sample of the effluent generated by the pine lamination process collected in an industry in the Southwest region of the state of Paraná confirmed the potential impact of the effluent, with emphasis on the high content of phenolic compounds (1,530 ±50 mg/L), color (2,159 ±30 units), significant acute toxicity (63% mortality of microcrustaceans Artemia salina) and low biodegradability (BOD/COD=0.53), which, if eventually released into receiving bodies, can cause irreversible and harmful effects to the aquatic microbiota. The treatment processes studied in this work involved catalytic ozonation mediated by ferrous catalytic material based on steel scale and biological process with Pleurotus Florida fungi, evaluated in an individual way and sequentially integrated as follows: Catalytic ozonation>>biological process and vice-versa. The best results were obtained by applying the sequence "catalytic ozonation>>biological process", which resulted in reductions of 96.2% in soluble lignin concentrations, 93.3% in color units and more than 99% reduction in total phenols, in addition to a low mortality rate of A. salina (≈10%). In the integrated process, the application of catalytic ozonation before the biological process presents greater advantages because of the pre-decomposition process of recalcitrant compounds by the chemical action of catalytic ozonation, which can convert these compounds into biodegradable, facilitating the action of the biological process for the remediation of the effluent.

1-12

Authors: Lisiana Crivelenti Voltolini; Reinaldo Gaspar Bastos ; Claudinei Fonseca Souza

The increasing demand for water in food production highlights the need to seek alternative sources of supply. Treated domestic sewage is a way to mitigate this problem, but it must comply with legislation to be used safely in agriculture. Ozone has been used for disinfection of domestic effluents due to its strong oxidizing character, allowing the adjustment of its parameters for agricultural reuse. This study therefore aimed to evaluate the sanitary and agricultural viability of domestic effluent treated with ozone. The experiment was carried out on laboratory benchtops and doses of 0, 8, 15, 30, 45, and 60 mg L−1 of ozone were applied. The application time for each dose was 0, 14, 27, 54, 81, and 108 seconds, respectively. Microbiological, physical, and chemical parameters were evaluated: total coliforms, Escherichia coli, pH, turbidity, dissolved oxygen, electrical conductivity, total organic carbon, total nitrogen, total phosphorus, potassium, magnesium, calcium, and sodium. Ozonation did not significantly alter the physical and chemical composition of wastewater, indicating an important advantage in terms of potential agricultural reuse. However, the pathogenic load of E. coli was not reduced enough for the effluent to be used in agriculture. The results suggest an investigation of the effects of ozone on the efficiency of sewage treatment, seeking to understand these interactions to identify ideal doses and exposure time, making wastewater safe for agricultural reuse.