Piotr Wichowski, Kamila Zalewska
Szkoła Główna Gospodarstwa Wiejskiego, Warszawa
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.
syfon, kanalizacja deszczowa, zawiesina mineralna, prędkość oczyszczająca
099. Experimental Studies on Removal of Mineral Suspension from Siphons in Rain Water Piplines
siphon, storm water drainage, mineral suspension, speed purifying
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Zadanie Czasopismo, Annual Set The Environment Protection Volume 17. Year 2015 (wersja elektroniczna) dofinansowane ze środków Ministerstwa Nauki i Szkolnictwa Wyższego