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The Study of Possibilities for Reuse of Washings from Swimming Pool Circulation Systems

Abstract

Swimming pools are very expensive, in terms of operation, sports facilities. Therefore, investors and managers of these facilities are looking for methods of reducing the costs of their use. One of the proposed methods is the managing of washings previously discharged to the sanitary sewage system. The assessment of possibilities for reuse of washings from swimming pool filtration system is based on the limits of basic indicators of pollutants in wastewater discharged to water and soil (temperature, pH, TSS, BOD5, COD, TN, TP, free chlorine). The conducted research of washings quality from 26 tested swimming pools have shown that washings quality is dependent on the operating conditions of the pool circuit, including the filter cycle duration and types of filter bed. A direct discharge to water or soil may be impossible due to excessive amounts of total suspended solids (above 35 mg/dm3) and free chlorine concentration (above 0.2 mg Cl2/dm3). However, the quality of supernatant water of washings subjected to sedimentation in the laboratory shows that the washings are suitable for reuse. The installation of settling tanks in swimming pool facilities could relieve the sewage systems and allow for the discharge of supernatant water to surface waters or for the irrigation of green areas in an environmentally friendly way.

Open access
Unconventionals in Europe: Best Practice vs. Worst Case - The Conflict Between Facts and Public Perception

Abstract

In spite of great progress in energy efficiency and in the development of renewable energy the world is likely to need significant amounts of fossil fuel throughout this century and beyond (the share of fossil fuels in the world mix has remained at about 86% of primary energy from 1990 to today). Gas, being the by far cleanest fossil fuel is the ideal bridging fuel to a world with predominantly renewable supplies. Thanks to the recent perfection of unconventional technologies there is no shortage of gas for this bridging function for at least the next 100-200 years. EASAC and several other European Institutions, notably the German Academy of Technical Sciences (acatech) have in the last few years carried out expert studies to assess the alleged environmental risks of unconventional hydrocarbon exploration and production. All these studies have, in agreement with other competent studies worldwide, come to the conclusion that there exists no scientific reason for a ban on hydraulic fracturing. With good practices, clear standards and adequate control the method causes no enhanced risks to the environment or the health of humans. Special attention has to be paid to the surface handling of drilling and fracking fluids. In Europe alone many thousand frac jobs have been carried out by the industry in the last 60 years without any severe accidents. The mishaps in North America have largely been the cause of unprofessional operations and human error. Especially in places with high air pollution, like many megacities of Asia, natural gas has to be seen as a unique chance to achieve a rapid improvement of the air quality and a significant reduction of CO2 emissions. This is also true for Europe where especially the use of domestic natural gas brings important benefits to the environment. The alternative to gas is in many regions of the world an increased consumption of coal, with all negative consequences.

Open access
Uptake of Metals from Single and Multi-Component Systems by Spirulina Platensis Biomass

Abstract

Spirulina platensis biomass is widely applied for different technological purposes. The process of lanthanum, chromium, uranium and vanadium accumulation and biosorption by Spirulina platensis biomass from single- and multi-component systems was studied. The influence of multi-component system on the spirulina biomass growth was less pronounced in comparison with the single-component ones. To trace the uptake of metals by spirulina biomass the neutron activation analysis was used. In the experiment on the accumulation the efficiency of studied metal uptake changes in the following order: La(V) > Cr(III) > U(VI) > V(V) (single-metal solutions) and Cr(III) > La(V) > V(V) > U(VI) (multi-metal system). The process of metals biosorption was studied during a two-hour experiment. The highest rate of metal adsorption for single-component systems was observed for lanthanum and chromium. While for the multi-component system the significant increase of vanadium and chromium content in biomass was observed. In biosorption experiments the rate of biosorption and the Kd value were calculated for each metal. Fourier transform infrared spectroscopy was used to identify functional groups responsible for metal binding. The results of the present work show that spirulina biomass can be implemented as a low-cost sorbent for metal removal from industrial wastewater.

Open access
Application of algae in active biomonitoring of the selected holding reservoirs in swietokrzyskie province

Abstract

During the years 2014-2015, biomonitoring studies were carried out at three holding reservoirs located in Swietokrzyskie Province (central Poland): Kielce artificial lake, Chancza reservoir and Sielpia reservoir. In sea water algae Palmaria palmata (Linnaeus) Weber & Mohr, exposed in the analysed waters, the increases of concentrations were determined by the atomic absorption spectrometry method (AAS), of the following: Mn, Fe, Cu, Zn, Cd and Pb. Conductivity and pH were also determined in the reservoirs waters. The differences between the increases of heavy metal concentrations in the samples of algae found along the coastline were indicated; they result from different distances from the pollution sources, such as resorts, communication routes and industrial plants.

Open access
Assessment of industrial contamination of agricultural soil adjacent to Sadat City, Egypt

Abstract

Assessment of the environmental impact of El Sadat City, a Cairo satellite, known for its clustered enterprises, on the neighbourhood water supply El Manashi Tawfikia Canal was undertaken through soil analysis. A total of 20 agricultural soil samples were collected along the El Manashi Tawfikia Canal. Neutron activation analysis was implemented to determine heavy metal contents of such elements as As, Ba, Co, Cr, Ni, and Zn. Multivariate statistical analysis was applied to the results obtained. The metal pollution index and enrichment factor were calculated. It was shown that the content of toxic heavy metals in soil samples does not exceed the worldwide-published values, except arsenic which considerably exceeds normalized to the content of the same element in the Upper Continental Crust. The metal pollution index is high compared with the calculated ones for similar soil samples from the Nile Delta, and the enrichment factor varied from moderate to high enrichment (5 < EF > 10).

Open access
The concept of well integrity in gas production activities

Abstract

Shale gas production in the US, predominantly from the Marcellus shale, has been accused of methane emissions and contaminating drinking water under the suspicion that this is caused by hydraulic fracturing in combination with leaking wells. Misunderstandings of the risks of shale gas production are widespread and are causing communication problems. This paper discusses recent preliminary results from the US Environmental Protection Agency (EPA) draft study, which is revealing fact-based issues: EPA did not find evidence that these mechanisms have led to widespread, systemic impacts on drinking water resources in the United States, which contrasts many broad-brushed statements in media and public. The complex geological situation and extraction history of oil, gas and water in the Marcellus area in Pennsylvania is a good case for learnings and demonstrating the need for proper analysis and taking the right actions to avoid problems. State-of-the-art technology and regulations of proper well integrity are available, and their application will provide a sound basis for shale gas extraction.

Open access
Effect of selected additions on de novo synthesis of polychlorinated dioxins and furans

Abstract

Polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans are generally considered the most dangerous chemical substances known to man. Although they have never been the product of purposeful human activity, yet they are formed in many chemical and virtually all thermal processes. Research on the occurrence of dioxins in the environment, their release into the environment, ways of formation and methods of reducing their emissions lasts since the late seventies of the last century. Currently, we know three basic pathways of dioxins formation in thermal processes, the most important of them being the so called de novo synthesis which occurs outside the combustion zone at 200-400°C in the presence of catalysts (eg copper) and oxygen from the products of incomplete combustion including carbon black and chlorine or chlorinated compounds. It is well known that some metals like copper catalyze the de novo synthesis, while others decompose dioxins and furans formed previously. The formation of dioxins resulting from the de novo synthesis was studied through analysis of the effect of the type of metal on the course of the de novo synthesis. The influence of the addition of sulfur, nitrogen and alkali metals on this synthesis was also examined because some reports in the literature refer to inhibitory effect of these elements.

Open access
Environmental contamination with phthalates and its impact on living organisms

Abstract

The relevant literature was reviewed to identify phthalate sources in the environment and problems resulting from phthalate contamination of soil and water. Phthalate properties responsible for their toxicity for living organisms were identified, and the effects of phthalates on humans and animals were described. Special emphasis was placed on the effects of exposure to phthalates on human health. Phthalates are readily released into the environment and create a risk of exposure for humans and other living organisms. They are characterized by reproductive toxicity in humans and animals, they can cause infertility and reproductive problems in males. Phthalates are more toxic in young children, which are much more susceptible to phthalate exposure, including fetal life. Phthalates are used in numerous industries, and they are very difficult to eliminate from our daily surroundings.

Open access
Evaluation of the possibility of the sewage sludge gasification gas use as a fuel

Abstract

Biomass is one of the major sources of energy that is estimated to contribute between 10% and 14% of the world’s energy supply. Over the past several years, many societies have established policy targets to increase their production of renewable energy from biomass. The thermo-chemical utilization of biomass includes 4 technologies: the most popular combustion and co-firing, and unconventional: pyrolysis and gasification. Gasification is considered to be the perspective technology because has many advantages in comparison to traditional process of combustion: (1) limited emission of the SO2, NOx, oxides of the heavy metals and no risk of the dioxins and furans emission due to reducing atmosphere in the gasification reactor, (2) volume of the gasification gas is smaller in comparison to flue gases from combustion due to the reducing atmosphere, (3) gasification process produce gas which is potential gaseous fuel in power engineering (engines, gas turbines and boilers) and chemistry. Unfortunately, composition of the gasification gas is always described as a variable. Moreover, it depends on the conditions of the process and quality of the base fuel. For this reason, the use of gasification gas can’t be very easy. For this reason, the knowledge of the basic properties of the gas is very important. Laminar burning velocity is assumed as an important quantity for in the process of the design equipment for the gas utilization. The numerical and experimental results of the laminar burning velocity of sewage sludge gasification gases were presented. Experimental Bunsen burner method was used. Cosilab 3© software for numerical analysis was used. GRI-Mech 3.0 mechanism of gas oxidation was implemented. As a result of the work, the set of the parameters where the sewage sludge gasification gas combustion process is stable with effective heat release, were presented.

Open access
Harmfulness of Septoria carvi Syd. towards caraway and preparations limiting occurrence of fungus

Abstract

Septoria carvi is an important pathogen of caraway. With the increasing occurrence of septoriosis of caraway during warm and humid growing seasons, the possibility of limiting the growth and development of the fungus was investigated. In vitro studies included 2 preparations of natural origin, ie Biosept Active, Beta-chikol and 12 fungicides from different chemical groups, as well as one isolate K 1806 S. carvi, obtained from caraway. Tests were performed by poisoning the culture media. The percentage of inhibition of the growth of four- and eight-day-old fungus colonies on the medium with preparations in comparison to the control colonies was a measure of the toxic activity of the preparations. The effectiveness of Beta-chikol in limiting S. carvi colony growth was significantly higher than the efficiency of Biosept Active. All tested fungicides limited the growth of the fungus colony and their inhibitory effect increased with the concentration of the active ingredient in the medium. The most effective preparation in vitro was Signum 33 WG, belonging to the strobilurin compounds. In vivo studies investigated the effect of Beta-chikol, Biosept Active and Dithane NeoTec 75 WG on the health of caraway plants. The occurrence of septoriosis was determined basing on the presence of disease symptoms and the mycological analysis of diseased plants. A significant reduction of septoriosis symptoms on plants and plant colonization by the fungus was caused by Biosept Active and Dithane NeoTec 75WG.

Open access