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Wastewater from car washes is the important environmental problem worldwide, both quantitatively and qualitatively. The goal of the article is to investigate the influence of the type and geometry of biofilm carriers on the efficiency of wastewater treatment in moving bed biofilm reactors. The experiments were conducted on laboratory models, in 4 types of biological reactors allowing treatment of 20 L of wastewater each. Three types of biofilter media were used as filling for the bioreactors: Mutag BioChip 30™, BioFLO 9 and Hel-X (H2X36 35/36), and the control group as reference. The tests were carried out for the retention times of wastewater in the bioreactors: 0 h (raw sewage), 1, 3, 6 and 20 h. In each measurement series, the following physical and chemical parameters were measured: organic matter chemical oxygen demand (COD), biochemical oxygen demand (BOD5), total nitrogen (TN) and total phosphorus (TP), colour, turbidity, pH and conductivity. The conducted experiments proved that the application of filter media (as a biological bed) in each of the tested variants resulted the significant reduction of analyzed wastewater parameters. The main research results indicated Mutag BioChip 30™ carriers as the most effective type of biological filter media. Bioreactors with the aforementioned carriers achieved up to 90% color removal and 94% suspended solids reduction in raw sewage. The COD and BOD5 reduction were also highly effective, reaching 66%-73% reduction, respectively. The removal of nutrients was also significant, with a reduction of 58% for TN and 68% for TP. The lowest treatment efficiency and circulation parameters were observed for Hel-X (H2X36 35/36) bed. [ABSTRACT FROM AUTHOR]

The development of effective methods to treat municipal wastewater is the current challenge of sustainable water management, the problem is particularly important and common in developing countries, but also applies to developed countries (e.g., in areas with scattered housing). Constructed wetlands are a solution with a particularly high potential to fulfill this need, especially as they are characterized by simple construction, reliability, economic performance and low electricity consumption. However, a huge challenge in their dissemination is the lack of comprehensive and credible design guidelines, generally reliable sources of knowledge for decision-makers and designers. The article analyzes barriers and needs in this respect and presents an online tool, that is, the Constructed Wetland Knowledge Platform. The article also analyzes the current resources of this platform, especially their potential and usefulness for designers of wastewater treatment solutions. The analyzes carried out in the article have shown that tools of this type can provide significant support in the selection of appropriate design solutions, as well as in professional designing of constructed wetlands. Thus, constituting a valuable tool for popularizing this solution in the world, as well as their practical application in various environmental, climatic, technical and even social conditions. [ABSTRACT FROM AUTHOR]

Fountains are decorative elements that improve the attractiveness and visual qualities of urban environments. They can give refreshment to residents on a hot, sunny day. Despite the prohibitions on bathing in these facilities people often have contact with fountain water. It should be emphasized that poor quality of water from fountains can be dangerous for human health. This study was aimed at evaluating microbial contamination of water in Krakow fountains (fountain from Szczepański Square, fountain on the Groble Square, "Chopin" fountain near the philharmonic, "Stone" fountain on the Maria Magdalena Square and the fountain on the Main Market Square). Microbiological analyses were conducted to determine the total number of microorganisms at 36±2°C after 48 hours (mesophilic bacteria) and the total number of microorganisms at 22±2°C after 74 hours (psychrophilic bacteria). In addition, the coliform bacteria, Escherichia coli and Closridium perfringens were also examined. The results have shown a high degree of microbiological contaminants in the tested water samples. The lowest contamination of water was observed in the fountain on the Szczepański Square and in nozzle water from the fountain on the Groble Square. The highest numbers of bacteria were found in "Stone" fountain at the Maria Magdalena Square. [ABSTRACT FROM AUTHOR]

Water is a significant source of macro -- and microelements, necessary for the proper functioning of a human body. The purpose of this article was to analyze the quality of the selected bottled waters available on the Polish market in terms of the physico-chemical parameters (pH, conductivity, chloride ions, bromide ions), macroelements (sodium, potassium, calcium, magnesium) and trace elements (lead, nickel, antimony, arsenic). 17 brands of the bottled waters available on the Polish market were investigated within the study presented in the article (8 natural mineral waters, 6 spring waters and 3 therapeutic waters). The bottled waters, which were analyzed in the article, characterized with a large diversity of chemical composition. In two samples of therapeutic waters the permissible concentration of nickel was exceeded. [ABSTRACT FROM AUTHOR]

The chlorine disinfectants are used to disinfect swimming pool water; in reaction with compounds dissolved in water, they cause the formation of many new substances, which are the disinfection by-products. Inorganic chloramines (mono-, di-, and trichloramine) also belong to this group of problematic substances. In a case of mono- and dichloramine, their negative effect on swimmers’ health has not been observed; however trichloramine can cause skin and eye irritation, as well as cause inflammation of the airways, potentially also asthma. The article presents the dynamics of trichloramine formation from the nitrogen compounds that are introduced into the pool water along with body fluids such as urea, creatinine, glycine, histidine, arginine, uric acid, hippuric acid, and ammonia. Beside the individual human body fluids, their mixture and the sample of swimming pool water were also studied. These studies were conducted for 1–79 h. The research results showed that the dynamics of trichloramine formation differ for particular compounds. Urea, creatinine, ammonia as well as hippuric acid react slowly with chlorine; however trichloramine concentration in water remains at a similar level in up to 6 h. In the case of arginine, despite the rapid depletion of free chlorine, trichloramine concentration remained high up to 24 h of incubation. Glycine, histidine, and uric acid are precursors, for which trichloramine was formed with the highest rate in the first hour of observation, after which the concentration of both trichloramine and free chlorine dropped rapidly. The studies have shown the other compounds present in swimming pool water can reduce the reactivity of free chlorine, and in the consequence the smaller formation potential for trichloramine occurs. [ABSTRACT FROM AUTHOR]

Influence of UV-chlorination sequence application on swimming pool water quality was investigated. In addition, an analysis of operating costs of such system was conducted. The study was based on a real facility, i.e. the swimming pool of AGH University of Science and Technology in Krakow. In the facility, water disinfection with calcium hypochlorite was carried out, assisted by UV irradiation. Switching the UV lamps temporarily off allowed for comparative studies on the quality of pool water disinfected by pure chlorination and by the UV and chlorination sequence. For these two variants of the swimming pool water disinfection several physico-chemical and microbiological parameters were analyzed, including the disinfection by-products. Cost analysis included the consumption of chemical agents and the UV lamp operation. It was established that the UV technology did not contribute to the expected improvement in the pool water quality in terms of the combined chlorine removal, however it did cause an increase in the concentration of selected organic chlorination by-products. Moreover, application of the UV lamp to the pool water treatment system increased the chlorine demand and, consequently, the consumption of calcium hypochlorite. Combined with the need to exchange lamp filaments, it raised the operating costs of the pool water treatment technology. [ABSTRACT FROM AUTHOR]

The article presents the results of experiments on the potential of model solutions of urea, creatinine, glycine, histidine, and arginine to form several organic chlorination by-products. These precursors are the main organic-nitrogen compounds, whose sources in swimming pool water are sweat and urine of bathers. In the article, the formation potential of the following by-products has been presented and discussed: trichloromethane; monochloroacetic acid; dichloroacetic acid; trichloroacetic acid; trichloroacetonitrile; dichloroacetonitrile; 1,1-dichloropropanone; 1,1,1-trichloropropanone; chloral hydrate; and chloropicrin. The test on by-products formation potential was applied to conduct the experiments, and 24-h incubation time was applied for the swimming pool water samples, disinfected in three variants of treatment: (1) chlorination alone; (2) chlorination and Ultraviolet (UV) irradiation (cumulative dose 23.5 kJ/m2); and (3) chlorination and UV irradiation (cumulative dose 47 kJ/m2). The low-pressure UV lamp by Heraeus was used to irradiate the samples. The results of experiments have been discussed and analyzed to study the influence of UV radiation on the reactivity of individual model precursors and their potential to form halogenated organic chlorination by-products. [ABSTRACT FROM PUBLISHER]

Dynamic development of road infrastructure and a significant increase in the number of cars are important challenges making it necessary to rationally treat and manage stormwater polluted with oil derivatives. Ecological engineering can be a source of valuable solutions in this domain, which are in agreement with sustainability principles, friendly to environment and hydrological cycle, convenient and attractive to the users. The article presents the results of research on using constructed wetlands to remove oil derivatives, which have been conducted with the semi-technical scale experimental installation planted withPhragmites australis, treating stormwater from a car service station in Sosnowiec. The results and discussion focus on the concentration of individual aliphatic hydrocarbons, their sum, as well as the efficiency of their removal by the studied installation. Some additional parameters of analysed wastewater such as temperature, suspended solids, pH, conductivity and air temperature have been also presented and discussed. The condition of the reed population has been also evaluated and discussed. The concentration of total aliphatic hydrocarbons (C7–C40) in raw wastewater was on average 2,311.67 μg/L (121.08–17,664.02 μg/L) and much lower in treated wastewater −261.81 μg/L (77.09–532.56 μg/L). All measured hydrocarbons concentrations in wastewater flowing out of the experimental installation were much lower than the standard value, defined by Polish law for wastewater released to the environment or to the sewage system. Some relatively high values of the aliphatic hydrocarbons removal rate were also observed (averagely 67% for C7–C40 and 64% for C7–C30). The analysis of research results in relation to individual aliphatic hydrocarbons showed that most efficiently removed ones were hydrocarbon C20–C33 (on average around 80%), C34–C40 and C12–C19 with slightly lower efficiency (60–70%), and least efficiently—lightest hydrocarbons C7–C11. Common reedP. australisconfirmed its high applicability in constructed wetlands which treat stormwater polluted with oil derivatives. Generally, the experiments confirm high potential of constructed wetlands to remove oil derivatives from wastewater. [ABSTRACT FROM PUBLISHER]

Application of UV radiation for water disinfection becomes more and more popular in Polish treatment plants that supply drinking water. UV disinfection is often sequentially coupled with chemical disinfection to prevent secondary growth of bacteria in water distribution systems. However, there are cases where directly after the UV disinfection water is pumped into a distribution system, without any additional chemical protection. The article presents results of the research on the influence of UV radiation on variations in water microbial stability in the distribution system supplied by Raba water treatment plant. Water samples were irradiated in laboratory conditions in the photochemical reactor (Heraeus) with the UV low-pressure lamp TNN 15/32. The UV doses of 400 J/m2, 1860 J/m2 and 10,000 J/m2 were applied. Water microbial stability was determined on the basis of heterotrophic bacteria growth rate in the period of up to 18 days. An analysis of the results demonstrated that UV radiation could adversely affect water microbial stability in distribution systems. The highest number of heterotrophic bacteria, over three-times higher compared to a purely ozonated sample, was recorded in the water sample irradiated with 400 J/m2. Higher doses of UV radiation as well as ozone/UV sequence improved water microbial stability, most likely due to organic matter mineralization. [ABSTRACT FROM AUTHOR]

The article discusses an impact of the sequence UV irradiation-chlorination on dynamics of by-product formation in water. UV irradiation of raw water can significantly influence the quantity and quality of naturally occurring organic matter (NOM). Consequently, this can affect NOM reactivity with the chlorine. A few publications on this subject show that chlorine produced electrochemically in water treatment plants contains, beside sodium hypochlorite, other strong oxidants, such as ozone, chlorine dioxide and free radicals. Thus it can influence the quality of organic matter and its potential to form water chlorination by-products. As the subject has been studied only recently, most research has been laboratory based. This article presents results of the research conducted on the real facility (the Raba Water Treatment Plant), where the water disinfection method was recently modernized. Water chlorination was replaced with the sequence of low-pressure UV lamp and chlorine produced electrolytically. Water samples collected from six distribution network endings, before and after the modernization, were taken for studies. The following parameters were measured in the samples: trihalomethanes, haloacetic acids, haloacetoni-triles, haloketones, chloropicrin and chloral hydrate. The result analysis showed that the water disinfection modernization caused decrease in the total concentration of analyzed chlorination by-products in Raba water distribution system. However, the increase was observed for chloral hydrate and nitrogen-containing disinfection by-products, especially haloacetonitriles. [ABSTRACT FROM AUTHOR]

Content of the following compounds in water has been examined: trihalomethanes (trichloromethane, bromodichloromethane, dibromochloromethane, tribromomethane), haloacetonitriles (bromochloroacetonitrile, dibromoacetonitrile, dichloroacetonitrile, trichloroacetonitrile), haloketones (1,1-dichloro-2-propanone, 1,1,1-trichloro- 2-propanone), chloropicrin and chloral hydrate. In the period of 2011-2012 samples from terminal ends of the two water distribution systems in Krakow: 'Raba' and 'Bielany' were collected and analyzed. These systems differ in raw water quality, treatment train arrangement as well as distribution network size. Chlorination to disinfect the water is applied in both plants. The result analysis allowed assessment of seasonal variations (spring, summer, autumn, winter) in individual volatile chlorination by-product group content for each of the considered water distribution systems. Research conducted demonstrated significant infl uence of season-related water temperature fluctuations, therefore of the amount and type of precursors present in chlorinated water, on volatile halogen disinfection byproduct content formed in the water distribution system. [ABSTRACT FROM AUTHOR]

Variations in halogen chlorination by-product formation potential after UV disinfection in four water treatment plants were studied. Formation potential of the following compounds has been examined: trihalomethanes (trichloromethane, bromodichloromethane, dibromochloromethane, tribromomethane), haloacetic acids (monochloroacetic acid, monobromoacetic acid, dichloroacetic acid, trichloroacetic acid, bromochloroacetic acid, dibromoacetic acid), haloacetonitriles (trichloroacetonitrile, dichloroacetonitrile, bromochloroacetonitrile, dibromoacetonitrile), haloketones (1,1-dichloropropanone, 1,1,1-trichloropropanone), chloral hydrate and chloropicrin. Water samples prior to and after UV irradiation were chlorinated with sodium hypochlorite at a dose resulting in 3÷5 gCl2/m³ of free residual chlorine after 24 h. The highest increase in the formation potential of all examined chlorination by-products was observed in water where the highest UV irradiation dose was applied. Additionally, it was stated that prior chemical oxidation may lead to increase in the examined product formation potential. It was proved that UV disinfection may also lead to increase in the amount of product bromide derivatives in water of high bromide content. Finally, nitration of organic compounds was demonstrated for water samples after UV irradiation. This phenomenon may lead to increase in nitrogen-containing chlorination byproduct content. [ABSTRACT FROM AUTHOR]

The goal of this paper is to analyze the Krakow water distribution systems regarding the occurrence of volatile halogenated water disinfection by-products from the group of trihalomethanes (trichloromethane, bromodichloromethane, dibromochloromethane, and tribromomethane), haloacetonitriles (bromochloroacetonitrile, dibromoacetonitrile, dichloroacetonitrile, and trichloroacetonitrile), haloketones (1,1-dichloro-2-propanone and 1,1,1-trichloro-2-propanone), chloropicrin (trichloronitromethane), and chloral hydrate. The research was conducted since February 2011 to March 2012; water samples were taken from the ends of the pipe system and analyzed. Two water distribution systems were selected for the research: the first one supplied with water from the water treatment plant (WTP) Raba, and second one--from WTP Bielany. These systems differ in water quality, applied water treatment processes, and the size of the water distribution system, however, in both plants chlorination is applied for the disinfection process. Each month, five samples were taken from the distribution system of WTP Bielany, and six samples from WTP Raba for research. During the entire research period, totally, 154 samples were taken (84 from WTP Raba distribution system and 70 from WTP Bielany one), in which 12 by-products were analyzed. The results of this analysis were used to assess the occurrence of volatile water disinfection by-products in the considered water distribution systems. [ABSTRACT FROM AUTHOR]