Kinetic analysis of constructed systems for the recovery of contaminated areas by acid mine drainage.
BACKGROUND
Flowing of the acid mine drainage may contaminate the adjacent water bodies causing substantial changes in the aquatic ecosystem. This aspect is the most relevant problem in the southern of Santa Catarina once the contaminated areas are inserted in the watershed of the Araranguá, Urussanga, and Tubarão rivers, increasing the need for recovery studies. These areas are between Criciúma, Içara, Urussanga, Siderópolis, Lauro Müller, Orleans, and Alfredo Wagner towns where a conservation unit exist called the Environmental Preservation Area of Baleia Franca. Aiming to compare the kinetics of the ash derived from burning coal and to neutralize acid mine drainage, different neutralizer, limestone, fly, and bottom ash, was mounted on a pilot scale experiment.


CONCLUSIONS
The transport parameters showed the same order of infiltration and dispersion: fly ash < bottom ash < limestone. The order of measured alkalinity was: limestone < fly ash < bottom ash, with pH values of 9.34, 12.07, and 12.25, respectively. The limestone kinetics of acidic drainage neutralization was first order with reaction rate constant k = 0.0963 min(-1), bottom ash was 3/4 with k = 0.0723 mol(1/4) L(-1/4) min(-1), and the fly ash had higher order kinetics, 4/3, with reaction rate constant k = 27.122 L(1/3) mol(-1/3) min(-1). However, by mathematical modeling, it was found that due to a combination of transport and kinetics, only limestone treatment reached a pH above 6 within 5 years, corresponding to the ideal as planned.
Environmental and Technology Research Institute-IPAT, University of Southernmost Catarinense (UNESC), Jorge Lacerda Street, km 4,5, Sangão District, 88806-000 Criciúma, SC, Brazil. erlon@unesc.net
Erlon
E
Mendes
Erilson
E
Barros
Jairo José
JJ
Zocche
Nadja Zim
NZ
Alexandre
Sérgio Luciano
SL
Galatto
Marcos
M
Back
Jader Lima
JL
Pereira
Jonathan
J
Frassetto
Elidio
E
Angioletto
D001938:Brazil; D060729:Coal Ash / Q000378:metabolism; D003032:Coal Mining; D052918:Environmental Restoration and Remediation / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D010865:Pilot Projects
D060729:Coal Ash