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EN
Concentrations of suspended sediment transported by rivers are influenced by interactions between multiple drivers that act on a range of spatial and temporal scales. Such levels vary over the year, as well as across multi-year periods. Most conventional approaches to determining suspended load are based upon analyses of total suspended sediment concentration (SSC), i.e., the sum of mineral and organic matter. This approach makes it difficult, if not impossible, to determine the impact of multiple environmental factors on changes in suspension concentration precisely. The present paper focuses on the mineral and organic components of suspended sediment with the aim of determining how our knowledge of the share of each individual component can improve interpretations of SSC fluctuations during a hydrological year. The analysis conducted (personal and other researchers’ results) has shown that mineral and organic suspensions demonstrate mutually incompatible opposite trends under influence of environmental factors. This analysis of organic components identifies clear seasonal trends, which indicates that organic suspensions of autogenous origin have a strong influence on the dynamics of changes in suspension concentration; such analyses are rarely included in assessments of SSC dynamics.
2
Content available remote Warunki przepływu wody z zawiesiną mineralną rurociągami z tworzyw sztucznych
PL
W artykule porównano liniowe straty hydrauliczne generowane w rurach z tworzyw sztucznych przy przepływie wody zawierającej różne stężenia zawiesiny mineralnej (piasku). Parametrami mierzalnymi były: natężenie przepływu, straty ciśnienia oraz temperatura medium. Pomiary wykonywano na stanowisku w rurociągach ciśnieniowych o średnicach 63, 75 i 90 mm, wykonanych z PVC i PE. Rurociągi ułożono w pętle bliskie koła, aby zminimalizować wpływ oporów miejscowych. Wykazano, że dla tych rur w badanym zakresie stężeń piasku (0 – 5568,3 mg/dm3) można uogólnić zależność liniowego współczynnika oporów λ od liczby Reynoldsa. Stwierdzono także, że stężenie piasku nie ma wpływu na współczynnik a we wzorze Fiodorowa [3], natomiast niewielki wpływ ma rodzaj i średnica rur. Wyznaczono szacunkowe wartości współczynnika oporów miejscowych dla połączeń rur PE i PVC.
EN
The article compares the major losses generated In the plastic pipes with a flow of water containing various concentrations of the mineral slurry (sand). Measurable parameters were flow rate, pressure loss and temperature of the fluid. Measurements were performed in pressure pipes made of PVC and PE with diameters of 63, 75 and 90 mm. Pipelines laid in loops close circle to minimalize impact of minor losses. It has been shown that for these pipes and used sand concentration (0 – 5568,3 mg/dm3) general relationship of major losses coefficient λ and Reynolds number can be given. Also it was shown, that sand concentration not has an effect on coefficient a in Fiodorow equation [3] and has a little effect type and diameter of the pipes. Determined the estimated values of the coefficient of minor losses for connections of PE and PVC pipes.
EN
The article presents a study on purifying rainwater pipes with mineral suspension. The study was divided into two stages. In the first stage determined the flow rate of conducive to self-cleaning rainwater pipes. The study was conducted for eight granulated mineral suspension for the straight line and the siphon positioned at an angle of 0°, 30°, 60°, and 90°. Determined the minimum speed at which there was no sedimentation of the slurry flowing in a stream of water and so-called. purification speed at which followed complete purification the measuring section of the accumulated mineral suspension. On the basis of a clear trend can be seen that with the decrease in grain size of grains we observe lower speed needed to remove them. In most cases, particularly for the finer fractions, the difference between the minimum speed and the speed of purification is less than the straight section. Taking as reference the average speed of straight horizontal purification for all the granulation, the speed for the siphon: arranged at an angle of 0° is about 3% higher, at 30° is about 16% higher, at an angle of 60° by about 8% higher, and to siphon arranged at an angle of 90° by about 33% higher. From the above indicates a paradox that the siphon with an inclination of 60° in order to clean the mineral suspensions requires an average water velocity less than the level of the proximal angle of 30°. The results were discussed and compared with the recommendations of [PN EN 1671: 2001]. Even the grain of the largest granulation moved at speeds below the normative 0.7 m/s, so it is a guarantee to achieve the removal of the tested types of suspension. At the second stage for specified speed measured self-cleaning wire flush time specified dose of the suspension. On the straight horizontal and horizontal sections of the siphon the suspension moves in the form of migrant suspension. It was observed that the migration speed of the bottom slurry is variable in time. Therefore, straight horizontal section measuring divided into four sections of equal length and the time of migration suspension by the individual sections. This time depends on the granulation suspension. Finer fractions are characterized by a slowdown in the speed of movement in subsequent sections, with larger fractions of the trend is reversed. Analyzing the cleaning duration of straight horizontal depending on the weight accumulated in the benthic suspension have failed to discern clear trends. This involves a much larger number of repetitions. In the case of the siphon with an inclination angle of 0° it was difficult to identify trends as for the horizontal section. When the siphon slope at 30° and 60° results of the measurements clearing time are common pattern. Higher dose of aggregate requires a longer time for cleaning. For the siphon with a slope of 90 degrees, regardless of the number of suspensions at speeds reaching purifying cleansing followed rapid siphon.
EN
An estimate of potential increase of sewage treatments plants' exploitation cost caused by returning pollution released in the processesraf initial cleansing into technological draft.
PL
Dokonano pomiarów przewodnictwa zawiesiny mineralnej w trakcie jej sedymentacji na różnych poziomach kolumny sedymentacyjnej. Obliczono profile stężeń ciała stałego w trakcie sedymentacji. Wyniki sedymentacyjne skorelowano z pomiarami potencjału dzeta.
EN
The electrical conductivity measurements of mineral suspensions under the different condition have been done. The concentration profiles during the sedimentation were calculated. The conductivity results were compared to the zeta potential of mineral particles.
PL
Treścią pracy są badania adsorpcji flokulantu i surfaktantu na granicy faz ciało stale roztwór. W badaniach stosowano flokulanty typu PEO (politlenek etylenu) o masie cząsteczkowej 300 000 i 5 000000 oraz anionowy surfaktant SDS (dodecylosiarczan sodu). Zawiesinę mineralną stanowiły drobnoziarniste (-40|mikrom) odpady po flotacji rudy Zn-Pb. Głównym składnikiem mineralnym odpadów był dolomit CaMg(CO3)2. Izotermy adsorpcji flokulantu w obecności surfaktantu i odwrotnie wskazują na silne współzawodnictwo w adsorpcji na powierzchni ciała stałego.
EN
The adsorption of both nonionic poly (oxyethylene) flocculants (MW 300,000 and 5,000,000) and surfactant (sodium dodecylsulphate) onto CaMg (CO3) 2 particles was studied. A displacement of the PEO adsorption from the mineral surface by addition of SDS molecules was observed. The plateau adsorption value of PEO decreased at the present of surfactant. In the presence of preadsorbed surfactant the adsorption of PEO 5,000,000 increased.
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