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PL
Przedstawiono zagadnienia związane z procesem tworzenia się aglo meratów cząstek podczas sedymentacji zawiesiny bentonitowej. Cząstki w zawiesinie powstały poprzez dodanie koagulantu, który wywołał efekt łączenia się frakcji rozproszonej w agregaty cząstek. W pracy przebadano wpływ kilku koagulantów na właściwości fizyczne tworzących się aglomeratów cząstek oraz wpływ użytych koagulantów na separację frakcji stałej.
EN
The bentonite suspension in water was coagulated using Al (PAX XL 19F and PAX XL 10) and Fe (PIX 100 and PIX 100 COP) coagulants. The size and shape of the resulting agglomerates were assessed using a Morphologi analyzer, and the grain size distribution was detd. using a Mastersizer 2000 laser diffractometer. The turbidity of the overlying wa ter was also detd. The best clarification effect and the most extensive structure were obsd. for the PAX XL 10, and the coagulant with the least impact on the formation of particle aggregates from the suspension was the PIX 100 COP. The effect of the coagulants used on the separa tion of the solid fraction were examined.
2
Content available remote Concept of new water tankfor dust collectingequipment controlling thedust hazard
EN
The article reviews the water reservoirs currently in use, working with wet-type dust collection devices. A shortcoming of current water systems is the problem of waste formation in the form of sludge with arelatively high water content. The article presents the concept and directions of further development of the device, in the context of thetreatment of water discharged from the dust collection device, operating in a closed circuit, and the impact of proper operation on theefficiency of the dust collection device, affecting the protection of the upper respiratory tract of workers who are in the area of increased dustiness. The use of a special design of the bottom of the tank makes it possible to separate the resulting pollution and direct it towards a drain hole or an inspection window. An important advantage of the presented solution is its modular design, which allows to adapt the development of the tank in conditions of limited space, and the way of its location and movement.
EN
This paper presents the results of tribological tests of lubricating compositions containing SN150 mineral oil as a base, an additive of solid lubricant in the form of hexagonal boron nitrides (h-BN) of various particle sizes (nano- and micro-) and surfactants: succinic acid imide and sodium di-2-ethylhexyl sulphosuccinate. Particular attention was paid to analysing the properties of hexagonal boron nitrides in the context of their effect on the tribological properties of the friction node under study. The effects of h-BN particle size, shape, specific surface area and porosity were considered. In addition, tests were carried out to check the surfactants' effect on the tested oil's hexagonal boron nitride sedimentation process. These tests confirmed the positive effect of succinic acid imide on maintaining a stable dispersion of h-BN particles in SN-150 mineral oil. Tribological tests were performed on a T-02 tribotester based on the PN-EN ISO 20623:2018-02 standard. The positive effect of hexagonal boron nitride on the lubricating properties of mixtures with SN150 mineral oil was established. In addition, hexagonal boron nitride, with a smaller particle size and a more developed porous structure, had a more favourable effect on improving the lubricity properties evaluated on the T-02 tribotester.
PL
W artykule przedstawiono wyniki badań tribologicznych kompozycji smarowych zawierających jako bazę olej mineralny SN150, dodatek smaru stałego w postaci heksagonalnych azotków boru (h-BN) o różnej granulacji cząstek (nano- i mikro-) oraz surfaktanty: imid kwasu bursztynowego oraz sól sodowa sulfobursztynianu di (2-etyloheksylu). Zwrócono szczególną uwagę na przeanalizowanie właściwości heksagonalnych azotków boru w kontekście oddziaływania na właściwości tribologiczne badanego węzła tarcia. Uwzględniono wpływ rozmiarów oraz kształtu cząstek h-BN, powierzchnię właściwą oraz porowatość. Dodatkowo wykonano testy sprawdzające wpływ surfaktantów na proces sedymentacji heksagonalnego azotku boru w badanym oleju. Testy te potwierdziły pozytywne działanie imidu kwasu bursztynowego na utrzymanie stabilnej dyspersji cząstek h-BN w oleju SN-150. Badania tribologiczne wykonano na tribotesterze T-02, opierając je na normie PN-EN ISO 20623:2018-02. Ustalono pozytywne działanie heksagonalnego azotku boru na właściwości smarnościowe mieszanin z olejem SN150. Ponadto heksagonalny azotek boru o mniejszej granulacji cząstek i bardziej rozbudowanej strukturze porowatej korzystniej wpływał na poprawę właściwości smarnościowych ocenianych na aparacie czterokulowym T-02.
PL
Przedstawiono rozpoznanie możliwości zastosowania koagulantów do separacji układów wielofazowych. Separacja jest procesem stosowanym w różnych obszarach gospodarki, takich jak ochrona środowiska, przemysł metalurgiczny i chemiczny. Przedstawiono badania określające podstawowe właściwości fizykochemiczne zawiesiny ziarnistej oraz koagulantów wpływających na efektywność procesu separacji. Ich celem było uzyskanie szczegółowych informacji na temat wpływu koagulantów na proces przemysłowego rozdzielania zawiesin. Badania dodatkowe pozwoliły sklasyfikować płyny pod względem reologicznym oraz określić ich lepkość.
EN
PAX XL 19F or PAX 16 coagulants were added to a model aq. suspension of PVC of a specific particle size and at various solid phase concns., mixed and left for phase separation. The turbidity of the overlying water after the separation process was detd., and the rheological tests of the hydrated solid phase were performed and its viscosity was detd. The suspensions formed with PAX XL 19F showed higher viscosity.
EN
Microalgae wastewater treatment technology has not only the function of wastewater treatment but also biomass production, resource recovery, and biological carbon fixation with significant economic and environmental benefits. Good sedimentation of microalgae cells is the key to realize wastewater treatment and microalgae cell proliferation. In this study, short settling time in sequence batch reactors (SBRs) was utilizable as an environmental selection pressure to promote the auto-flocculation of Chlorella vulgaris treating synthetic domestic wastewater. After 60 days of operation, bacteria-microalgae consortia formed in the reactors, improving the settling efficiencies. Microalgae cultivation reactor with 30 min settling time had the largest flocs size and highest settling efficiency. Bacteria-microalgae granular sludge had a relatively high content of P, Fe, Mg, and Ca elements that both bacteria and microalgae coexisted and adhered to each other. The dominant bacteria distribution of bacteria-microalgae granular sludge was like that of aerobic granular sludge, which implied bacteria played a vital role in Chlorella vulgaris auto-flocculation. Lastly, the mechanism of Chlorella vulgaris auto-flocculation in wastewater treatment was interpreted.
EN
Sediment deposition is a natural process that occurs in all reservoirs, resulting in significant storage loss, which has an adverse effect on the economic development of the local area. It is necessary to take appropriate action to control the sedimentation and prevent loss of the storage capacity of the reservoir. In the present study, runoff and sediment data collected at the Konijerla hydrometric station of Wyra reservoir for the period of 1991 to 2019 are used. Data from 2011 to 2016 is used to calibrate and the data from 2017 to 2019 is used to validate the SWAT model. The Wyra watershed consists of 26 sub-basins and 47 HRUs (Hydrological Response Units). Out of these sub-basins, one of the sub-basins is contributing 18.8% of sedimentation. It was also observed that two other sub-basins, though less in area, generate high sediments. Seasonal sediment analysis showed that sedimentation increased by 12% in the month of August for wet years. Overall sedimentation increased in wet years by 10.60% and in dry years, it decreased by 18.78%. The SWAT model was satisfactory in the calibration and validation periods for various parameters used. Hence, this model can be used for sedimentation study, as well as a planning tool in the reservoir capacity management.
EN
The coalbed methane content (CMC) is an important parameter to evaluate the degree of coalbed methane enrichment, and also an important reservoir parameter to calculate coalbed methane resources, productivity prediction and reservoir simulation. Accurately identifying the distribution of CMC is crucial to the exploration of CBM. In this study, we developed a prediction method for the CMC distribution via seismic techniques identification of key geological parameters such as structure, coal thickness and sedimentation. Firstly, the geological factors that control the generation and preservation of CBM in the study area are quantitatively characterized by using five parameters: surface (X1), residual (X2), dip (X3), coal thickness (X4) and the ratio of sand to mud (X5). Secondly, the geological parameters are extracted by seismic structure interpretation and inversion prediction technology. Thirdly, the key geological parameters of CMC are screened out by grey correlation analysis. Finally, the functional relationship of CMC and the key geological parameters is established to predict the CMC distribution. The method is applied to the CMC distribution prediction of two coal seams of a study area in the southern Qinshui Basin, China. Results show that different coal seams differ in key geological parameters of CMC, resulting in various CMC distribution laws. The CMC prediction method based on the key geological factors can effectively delineate the CBM enrichment area in the study area, providing important reference for the CBM exploration and development.
PL
Zamieszczono wyniki badań i analiz procesu oczyszczania zawiesiny pochodzącej z odwadniania kopalń. Prowadzone prace miały na celu określenie parametrów procesu oczyszczania zawiesiny pochodzącej z zakładu górniczego, obejmującego strącanie chemiczne z wykorzystaniem wodorotlenku sodu oraz mleczka wapiennego, a także separacji wytrąconej frakcji w wyniku edymentacji. Przeprowadzono badania sedymentacji w warunkach statycznych w celu określenia przebiegu procesu sedymentacji. W szczególności wyznaczono prędkość sedymentacji zawiesiny po procesach strącania wodorotlenkiem sodu oraz mleczkiem wapiennym.
EN
Slurry samples from two intakes from one of the mining plants were pptd. with 2 M NaOH and then with a 12% Ca(OH)₂ soln. The sedimentation rate of the suspension after pptn. processes under static conditions was studied. The way the process was carried out had a very significant impact on the course of the sedimentation and the degree of sludge concn.
EN
Erosion and sedimentation have a very big influence on flooding. Floods are strongly influenced by land use and population activities that change the river’s physical condition, including erosion and sedimentation. The river upstream was very steep, and the downstream was narrowing and meandering with high rainfall recorded. This study analyses erosion, sedimentation, and its handling using the eco-hydraulic base. The method involves input rainfall data, river hydraulics, land use, watershed area, and land cover. The analysis of hydrology, hydraulics, land use, flood discharge, and eco-hydraulic, inundation height, vegetation diameter, velocity reduced, and riverbank width measured in five bridges cross-sections along the river. The eco-hydraulic compares the width of existing riverbanks and design, high inundation, and the vegetation diameter to minimise flood discharge. Erosion in the right cliff is 22.73% and the left cliff is 37.04%, land erosion was 225.83 Mg∙ha-1∙year -1. The river’s bottom is formed by rocks of 0.18-1.30 mm. The plantation land used around the Lae Kombih River grows mainly an oil palm with a diameter of 0.5-0.7 m. The riverbank design on 100 m for vegetation diameter of 0.1-1.0 m can retain flood discharge for five years return period up to 72.3%, resulting in discharge of 112.04209.43 m3∙s-1. The largest erosion and sedimentation on the river border is Dusun Silak, so it is recommended to plant Vetiveria zizanioides, Ipomoea carnea and Bambusoideae. An inundation height of 0.9 m can be recommended to design an embankment to be used as flood mitigation.
EN
Changing coastal zones in Indonesia, such as coral reefs, seagrass, and mangroves, have an impact on tropical ecosystems. Excessive exploitation and sedimentation, in particular, have threatened the mangrove at Segara Anakan Cilacap. In order to evaluate temporal land cover changes and the impact of high siltation on the Segara Anakan lagoon system in Cilacap, Indonesia, a research was conducted. The land cover data from SPOT 4 was available in 2008, and the Sentinel-2A data was available in 2019. The Normalized Difference Vegetation Index (NDVI) was used to enhance the Macro Class with supervised classification utilizing Maximum Likelihood techniques. Mangroves and water bodies declined between 2009 and 2019, whereas settlements and farmland areas increased, according to this study. In the western part of Segara Anakan, extensive siltation altered the biomass, structure, and composition of mangrove vegetation. At high sedimented habitats, Acanthus and Derris dominate, followed by Nypa. The changes in land cover and land use had an impact on socioeconomic factors. Decreases in water bodies and mangrove areas, as well as an increase in farmland, were significantly linked to a shift in society’s livelihoods from fishermen to farmers. The destruction of mangrove habitats in the Segara Anakan has been accelerated by anthropogenic activity and population pressure. Because this sensitive environment is constantly threatened by anthropogenic activity and climate change, effective management of the Segara Anakan Lagoon mangrove ecosystem is important for its long-term viability.
EN
Over a long period of time, a huge amount of technogenic bottom sediments has been accumulating in the Kosva Bay with significant concentrations of amorphous iron and aluminium hydroxides, which, in turn, are active sorbents of pollutants. This study examines the distribution of trace elements and rare earth elements and their toxicity in the Kosva Bay of the Kama Reservoir (Perm Region, Russia). In the middle reach, the Kosva River crosses the Kizel coal basin, where acid mine water is discharged from closed mines. The average content of trace elements in the samples of bottom sediments of the bay varies from 0.10 mg/kg (Se) to 176.36 mg/kg (Ba). The amount of rare earth elements varies from 66.8 to 83.6 mg/kg. The ecological significance of trace elements and rare earth elements was studied using an element-by-element assessment (EF and Igeo), Potential Ecological Risk Index (RI), Mean Probable Effect Concentration Quotient (PECQ), and two bioassays (Daphnia magna Straus and Scenedesmus quadricauda (Turp.) Breb. The highest Hg enrichment was found at two sampling points. Taking into account the average value of Igeo, the pollution by Co, V, Nb, Hg, Sn, Zn, Sm, Ni, Cr, and Gd is the highest and corresponds to extremely contaminated category. The RI values indicate that pollution categories vary from moderate risk to considerable risk. According to mean PECQ values, bottom sediments of the bay have moderate potential toxicity towards biological communities. Results of chronic and acute toxicity on test objects D. magna and Scenedesmus quadricauda Breb show the water extract from bottom sediments having no effects on the test objects. The results of the study show that in order to assess the quality of bottom sediments, an integrated approach, combining chemical and ecotoxicological analyses, is needed.
EN
Water pollution in rivers is still a crucial problem for the countries that use river water as the primary water source. This study aimed to determine the water quality of the Musi river and the content of heavy metals in water, sediment and mussels as well as to predict the water quality of the Musi river in the next five years. The water samples were taken from 18 stations (sampling points) from upstream to downstream to be checked physically, chemically and biologically. Prediction of the river water quality was made using the QUAL2Kw software. The research results show that the Musi River water is categorized as lightly polluted with concentrations of TSS and DO that have passed the threshold. The heavy metals in river water, such as Pb and Cr have also passed the quality standard. The Fe, Mn, and Zn concentrations are pretty high in the sediment. In turn, in mussels, the metals measured were Fe, Cu, and Zn. The prediction results reveal that several values of the river quality parameters will pass the threshold value with the same pattern tendency from each station.
14
PL
W Instytucie Chemii Nieorganicznej w Gliwicach opracowano metodę otrzymywania nano - ZnS na nośnikach nieorganicznych, trwale związanego z nośnikami, charakteryzującego się stosunkowo niską zawartością cynku. Uzyskany materiał o bardzo dobrze rozwiniętej powierzchni, powinien być wielofunkcyjnym materiałem w farbach i tworzywach. Mógłby pełnić w nich role białego pigmentu nieorganicznego, środka opóźniającego palenie, środka powodującego samooczyszczanie zawierających go materiałów, szerokopasmowego półprzewodnika oraz luminoforu. Uzyskane zawiesiny wymagają wstępnego zagęszczenia metodą sedymentacji przed końcową operacją rozdziału faz. Głównym celem było przeprowadzenie testów sedymentacyjnych, które pozwoliło na wyznaczenie krzywych sedymentacyjnych, a na ich podstawie opracowano wyniki rzeczywistych prędkości zawiesin poreakcyjnych nano-siarczku cynku na nośniku krzemionkowym i nano-siarczku cynku na nośniku montmorylonitowym. Analizowano optymalne parametry operacji sedymentacji stosując modele obliczeniowe dla prędkości teoretycznych/ względnych , które są niezbędne podczas doboru lub w projektowaniu odpowiednich odstojników.
EN
At the Inorganic Chemistry Division in Gliwice a new method has been created for the production of nanoparticles ZnS on inorganic supports, permanently bound to said supports and characterized by relatively low zinc content. The resulting product with highly developed surface should prove to be a multi-purpose component for paints and materials in which it could serve as an inorganic white pigment, a flame retardant, a self-purification trigger, a broadband semiconductor or a phosphor. The obtained suspensions require preconcentration by means of sedimentation prior to the final operation of phase separation. The main objective was to conduct sedimentation tests which allowed for determining the sedimentation curves. Those served as a basis for determining actual post-reaction suspension velocity data for nanoparticles ZnS on silica support and nanoparticles ZnS on montmorillonite support. The optimal parameters for sedimentation operations were analysed with the use of computational methods for theoretical/ relative velocities, which are indispensable during the selection or designing of appropriate settlers.
PL
W kopalniach podziemnych woda pochodząca z naturalnych dopływów oraz woda technologiczna pochodząca głównie z sieci rurociągów przeciwpożarowych gromadzona jest w osadnikach znajdujących się najczęściej na najniższym poziomie kopalni. Zwykle jest to woda zanieczyszczona mechanicznie. Gromadzenie się osadu odbywa się na zasadzie sedymentacji. W artykule przedstawiono metodę oczyszczania osadników wód kopalnianych opartą na zasadzie hydrourabiania i hydrotransportu oraz sposób segregacji na część stałą, czyli osad, i wodę. Konsystencja otrzymanego osadu pozwala na jego transport, np. za pomocą przenośnika, a woda może być ponownie wykorzystana w procesie hydrourabiania osadu. Do tego celu stosuje się urządzenia z serii ZEKO.
EN
In mines, water from natural inflows as well as process water from fire protection systems is usually stored in sedimentation tanks, located primarily at the lowest level of the mine. Such water usually contains mechanical contaminants, undergoing the process of sedimentation. The article presents a method enabling the cleaning of mine water sedimentation tanks. The method involves jet mining, hydrotransport and segregation into sediment (i.e. the solid fraction) and water. The consistence of sediment obtained after segregation makes the former transportable (e.g. using an appropriate conveyor/feeder), whereas water can be reused subsequently in the jet mining of sediment. One of the solutions enabling the performance of the above-named process is a ZEKO series system
EN
In mines, water from natural inflows as well as process water from fire protection systems is usually stored in sedimentation tanks, located primarily at the lowest level of the mine. Such water usually contains mechanical contaminants, undergoing the process of sedimentation. The article presents a method enabling the cleaning of mine water sedimentation tanks. The method involves jet mining, hydrotransport and segregation into sediment (i.e. the solid fraction) and water. The consistence of sediment obtained after segregation makes the former transportable (e.g. using an appropriate conveyor/feeder), whereas water can be reused subsequently in the jet mining of sediment. One of the solutions enabling the performance of the above-named process is a ZEKO series system.
PL
W kopalniach podziemnych woda pochodząca z naturalnych dopływów oraz woda technologiczna pochodząca głównie z sieci rurociągów przeciwpożarowych gromadzona jest w osadnikach znajdujących się najczęściej na najniższym poziomie kopalni. Zwykle jest to woda zanieczyszczona mechanicznie. Gromadzenie się osadu odbywa się na zasadzie sedymentacji. W artykule przedstawiono metodę oczyszczania osadników wód kopalnianych opartą na zasadzie hydrourabiania i hydrotransportu oraz sposób segregacji na część stałą, czyli osad, i wodę. Konsystencja otrzymanego osadu pozwala na jego transport, np. za pomocą przenośnika, a woda może być ponownie wykorzystana w procesie hydrourabiania osadu. Do tego celu stosuje się urządzenia z serii ZEKO.
EN
Changes in land use as a result of human activities may generate the alteration of hydrometeorological disasters. Erosion, sedimentation, floods and landslides frequently occur in the Sanenrejo watershed (±292 km2), located in East Java, Indonesia. In this paper, the soil and water assessment tool (SWAT) model is used to evaluate the hydrological processes in this small watershed. The digital elevation model (DEM) is used as the primary input for deriving the topographic and physical properties of the watershed. Other input data used for the modelling processes include soil type, land use, observed discharge data and climate variables. These data are integrated into the SWAT to calculate discharge, erosion and sedimentation processes. The existing observed discharge data used to calibrate the SWAT output at the watershed outlet. The calibration results produce Nash–Sutcliffe efficiency (NSE) of 0.62 and determination coefficient (R2) of 0.75, then the validation result of 0.5 (NSE) and 0.63 (R2). The middle area faced the highest erosion and sedimentation that potentially contribute to hydrometeorological disasters.
EN
The presented study aimed to compare the effectiveness of ultrafiltration and filtration through a sand bed during the water treatment process after the coagulation and sedimentation. The study was conducted in two flow-type water treatment systems: the reference and the test system. Both systems functioned continuously with a throughput of 1 m3/h. The research has shown that both processes ensured a very effective removal of post-coagulation suspensions, however, ultrafiltration was more effective. The filtration process allowed a slightly higher removal of organic substances as compared to ultrafiltration. The effectiveness of the removal of organic substances was determined by the biological activity of sand beds, which is not allowed in the ultrafiltration process. Besides, during the filtration process, aluminum remaining after coagulation was more effectively removed. In turn, the ultrafiltration process ensured an almost 100% effectiveness in reducing the total microorganism cell count, while the effectiveness of the filtration process was approximately half of that. In the end, the possibility of replacing the filtration process with the ultrafiltration process is determined by the costs of both processes.
EN
The stratigraphical interval of the Kimmeridgian between the Bimammatum and the Hypselocylum zones in the SW margin of the Holy Cross Mts. shows a transition from the open shelf deep-neritic sponge megafacies to the shallow-water carbonate platform, including its development and decline. The uniform progradation of the shallow-water carbonate platform occurred at the end of the Planula Chron. Development of the shallow-water carbonate platform was controlled by climatic and tectonic factors. The former induced by orbital cyclicity resulted in changes of sea-level, revealed i.a. by the incoming of open-marine ammonite faunas, the latter were related to the synsedimentary activity of faults which resulted in contrasted facies changes. The episodically occurring strong influx of siliciclastic material was at least partly controlled by the tectonic activity. The newly elaborated formal lithostratigraphic subdivision takes into account the facies development of the succession in relation to climatically and tectonically induced changes. Such is e.g. the Małogoszcz Oolite Formation, corresponding to a single 100-kyr eccentricity cycle from the late Platynota Chron to the earliest Hypselocyclum Chron, bordered from the base and top by two transgressive climatically-controlled levels. The final stage of the shallow-water platform development at the end of the Hypselocyclum Chron was marked by the successive limitation of restricted environments, and the appearance of more open-marine conditions related to tectonic subsidence of the area of study. Comparison between the carbonate platform development of the Holy Cross Mts. in central Poland, and the coeval shallow-water carbonates of the Jura Mts. in northern Switzerland and south-eastern France provides an opportunity to consider similarities in the successions which can be attributed to the climatically-controlled sedimentary cyclicity and/or the wide-ranged tectonic phenomena. The palaeontological part of the study gives comments on the classification and phylogeny of ammonites of the families Ataxioceratidae and Aulacostephanidae.
20
Content available remote Modelowanie parametryczne zapisu krzywych sedymentacyjnych
PL
Podjęto próbę matematycznego modelowania zjawisk zachodzących podczas testu sedymentacyjnego. Omówiono ten test oraz metody wykreślania krzywych sedymentacyjnych. Test sedymentacyjny jest pierwszym, wstępnym narzędziem stosowanym przy modelowaniu procesu zagęszczania zawiesin. Zaproponowano równania opisujące zbiór punktów pomiarowych z wykorzystaniem współczynników równania. Zastosowanie opracowanego narzędzia pokazano na przykładzie krzywych sedymentacyjnych dla procesu zagęszczania zawiesiny węglowej.
EN
Exptl. sedimentation curves were approximated by exponential equations. Coeffs. of the equation were detd. for concentrating the coal dust suspensions. The calcd. curves agreed well with exptl. ones.
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