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Changes in Water Quality for Sprinkler Irrigation in Selected Lakes of the Poznan Lake District

Stachowski Piotr, Rolbiecki Stanisław, Jagosz Barbara, Krakowiak-Bal Anna, Rolbiecki Roman, Figas Anna, Gumus Mehmet, Atilgan Atilgan

Journal of Ecological Engineering

2023

Vol. 24, nr 11

69--81

The rapidly changing quality of irrigation water requires urgent attention to understand and predict the long-term effects on soils and food crops, especially in a situation of global freshwater scarcity. The aim of the research was to assess changes in water quality in two selected lakes located in Poland in 2009–2016. The study was carried out in terms of the possibility of using selected reservoirs as sources of water for sprinkler irrigation of agricultural crops. The presented analysis was compared with a similar one carried out in 1999–2006 and 2004–2009 to determine the historic and present water quality state. Results indicate, that the source of pollution of the lakes is most often outflows from sewerage systems, the precipitation and surface runoff from the catchment areas of these lakes, which are mainly used as agricultural land. In Lake Niepruszewskie, the oxygen conditions, water transparency, phosphorus content, sestone dry matter and coliform titre increased, while the biological oxygen demand (BOD5), nitrogen, and chlorophyll content decreased. According to present research, in the Strykowskie Lake, the phosphorus content and BOD5 decreased, while the sanitary condition, nitrogen content and oxygen conditions deteriorated. The reduction of mineral fertilization in recent years has reduced the degradation of the lakes and allowed the water quality to remain in Class III of purity. Despite the visible improvement in the general condition of both studied lakes, constant monitoring of their quality is necessary, which is obligatory for the water from these reservoirs to be used for sprinkler irrigation of crops.

Monitoring of contamination of coal processing plants and environmental waters using bubble velocity measurements – advantages and limitations

Zawala J., Malysa E., Krzan M., Malysa K.

Physicochemical Problems of Mineral Processing

2014

Vol. 50, iss. 1

143--157

The paper presents fundamentals of a simple physicochemical method (SPMD) and analysis of results obtained when the method was applied for detection of organic contaminations (surface-active substances SAS) in samples of environmental and industrial waters. The method is based on measurements of variations of air bubble local velocities, which can be significantly changed in presence of surface-active contaminants. Lowering of the bubble velocity is a consequence of a motion induced dynamic adsorption layer (DAL) formed over surface of the rising bubble. The DAL formation retards the surface fluidity and the bubble rising velocity can be lowered by over 50% when the bubble surface is completely immobilized. We showed that the SPMD is a very sensitive tool (detection limit even below 1 ppm) for detection of various kinds of surface-active substances (ionic, non-ionic) in water samples. On the basis of results obtained using precise laboratory set-up, an accuracy of the SPMD is discussed. Moreover, effect of inert electrolyte addition on the bubble velocity lowering and value of detection limit of the SPMD is discussed. Simple approach, enabling quantitative analysis of the surface-active contaminants in samples collected, based on “equivalent concentrations” determination, is proposed. Results obtained for industrial (Jankowice and Knurow coal processing plants, Jaslo Refinery channel) and environmental waters (Wisloka and Ropa river) are used for detailed analysis and critical discussion of advantages and limitations of the SPMD.

Ocena wpływu stopnia czystości wody na proces aeracji w mieszalniku

Wesołowski P.

Zeszyty Naukowe. Inżynieria Chemiczna i Procesowa / Politechnika Łódzka

2000

Z. 28

219-224

W pracy dokonano porównania wyników napowietrzania wody o różnym stopniu czystości w reaktorze zbiornikowym podczas barbotażu z mechanicznym mieszaniem. Badania aerowania wody destylowanej, wodociągowej i rzecznej przeprowadzono w identycznych zakresach zmienności parametrów operacyjnych z zachowaniem stałości inwariantów geometrycznych układu mieszadło-zbiornik. Uzyskane wyniki pozwoliły stwierdzić, że nieznaczna różnica w czystości napowietrzanej wody nie wywiera istotnego wpływu na ilość zatrzymywanego w niej powietrza. Występujące w literaturze poważne rozbieżności dotyczące przebiegu procesu aeracji w tego typu układach nie mogą zatem być uzasadniane różnym stopniem czystości wody.

This paper reports the results of the experimental studies performed for three gas-liquid systems. The gas hold-up was measured for dispersion of air in distillate, tap and river water, in cylindrical tank using Rushton turbine. The experimental data obtain for all investigated systems have been compared.