Modelling of coalescence in turbulent liquid/liquid dispersions considering droplet charge

• Autorzy: Kamp J. , Nachtigall S. , Maaß S. , Kraume M.

Warianty tytułu

PL

Wzory koalescencji w turbulentnych dyspersjach między płynami w odniesieniu do ładunku kropelki

• Języki publikacji: EN

Abstrakty

EN

Drop size distributions in liquid/liquid systems within a turbulent flow, being an integral part of many technical applications, can be simulated solving population balance equations. Experimental investigations in stirred toluene/water systems at constant ionic strength of 0.1 mol/L showed that with pH values higher than 11, coalescence is hindered considerably due to electrostatic effects. Within this work, two designated models are used to simulate the transient drop size distributions in a stirred tank, showing that the influence of droplet charge due to a change in pH value or ion concentration cannot be predicted satisfactorily by existing models. This finding motivates a new modelling approach implementing the DLVO theory into the population balance framework.

PL

Nierównomierne rozmieszczenie w przepływie turbulentnym w układach między płynami, stanowiących integralną część wielu urządzeń technicznych, można symulować przez rozwiązywanie równań równowagi populacji. Badania doświadczalne w zakresie mieszanych układów toluen/woda przy stałej sile jonowej 0,1 mol/L pokazały, że przy wartościach pH przekraczających 11 koalescencja jest znacznie utrudniona ze względu na efekty elektrostatyczne. W pracy niniejszej wykorzystano dwa przydzielone modele symulujące nierównomierne rozmieszczenie przejściowe w mieszanym zbiorniku. Za pomocą istniejących modeli nie można wiarygodnie prognozować wpływu ładunku kropelki po zmianie wartości pH lub stężenia jonu. Odkrycie to stanowi motywację dla nowej taktyki realizowania teorii DLVO w zakresie równowagi populacji.

Słowa kluczowe

EN

population balance equation; coalescence; electrostatic force; droplet charge

PL

równanie równowagi populacji; koalescencja; siła elektrostatyczna; ładunek kropelki

• Wydawca: Wydawnictwo Politechniki Krakowskiej im. Tadeusza Kościuszki
• Czasopismo: Czasopismo Techniczne. Mechanika
• Rocznik: 2012
• Tom: R. 109, z. 1-M
• Strony: 113--124
• Opis fizyczny: Bibliogr. 28 poz., wz., tab., wykr.

Twórcy

autor

Kamp J.

• Chair of Chemical and Process Engineering, TU Berlin

autor

Nachtigall S.

• Chair of Chemical and Process Engineering, TU Berlin

autor

Maaß S.

• Chair of Chemical and Process Engineering, TU Berlin

autor

Kraume M.

• Chair of Chemical and Process Engineering, TU Berlin

Bibliografia

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