The effect of shear rate on aggregate size distribution and structure at steady state: a comparison between a Taylor–Couette reactor to a mixing tank

Kód výsledku v IS VaVaI

RIV/67985874:_____/13:00393135 - isvavai.cz

Výsledek na webu

https://iwaponline.com/aqua/article-abstract/62/5/288/29147/The-effect-of-shear-rate-on-aggregate-size?redirectedFrom=fulltext

DOI - Digital Object Identifier

10.2166/aqua.2013.005

Jazyk výsledku

angličtina

Název v původním jazyce

The effect of shear rate on aggregate size distribution and structure at steady state: a comparison between a Taylor–Couette reactor to a mixing tank

Popis výsledku v původním jazyce

The paper deals with the dependence of aggregate properties on the shear rate (G) at steady state. Aggregation of natural raw water and ferric sulphate was carried out in a laboratory Taylor–Couette reactor (TC) and continuous flow mixing tank (MT) with a paddle stirrer. Shear rates in the range of 20–350 s -1 were used.Methods of image and fractal analyses were used to determine the aggregate size and structure, respectively. It was found that the aggregate size decreased with increasing shear rate. There was a small difference in sizes of aggregates formed in TC and MT at G< 150 s -1, but at higher shear rates, almost no difference between TC and MT was observed. The D2 fractal dimension increased with increasing shear rate indicating that aggregates became less porous andmore compact. Moreover, a very closematch in D2 valueswas attained for both mixing devices. The Dpf fractal dimension decreased with increasing shear rate meaning that aggregates were more regular at higher shear rates, but jagged on the surface with irregular shape at lower shear rates. In contrast to D2, aggregates formed in MT were much more irregular (jagged) than those formed in TC.

Název v anglickém jazyce

The effect of shear rate on aggregate size distribution and structure at steady state: a comparison between a Taylor–Couette reactor to a mixing tank

Popis výsledku anglicky

The paper deals with the dependence of aggregate properties on the shear rate (G) at steady state. Aggregation of natural raw water and ferric sulphate was carried out in a laboratory Taylor–Couette reactor (TC) and continuous flow mixing tank (MT) with a paddle stirrer. Shear rates in the range of 20–350 s -1 were used.Methods of image and fractal analyses were used to determine the aggregate size and structure, respectively. It was found that the aggregate size decreased with increasing shear rate. There was a small difference in sizes of aggregates formed in TC and MT at G< 150 s -1, but at higher shear rates, almost no difference between TC and MT was observed. The D2 fractal dimension increased with increasing shear rate indicating that aggregates became less porous andmore compact. Moreover, a very closematch in D2 valueswas attained for both mixing devices. The Dpf fractal dimension decreased with increasing shear rate meaning that aggregates were more regular at higher shear rates, but jagged on the surface with irregular shape at lower shear rates. In contrast to D2, aggregates formed in MT were much more irregular (jagged) than those formed in TC.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10305 - Fluids and plasma physics (including surface physics)

Projekt

GAP105/11/0247: Charakterizace organických látek produkovaných sinicemi a řasami a jejich vliv na koagulaci a flokulaci

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2013

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Water Supply Research and Technology. AQUA

ISSN

0003-7214

e-ISSN

—

Svazek periodika

62

Číslo periodika v rámci svazku

5

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

8

Strana od-do

288-295

Kód UT WoS článku

000322708000004

EID výsledku v databázi Scopus

2-s2.0-84882755412