Weathering of waste rock in different climatic conditions – a kinetic freeze/thaw and humidity cell experiment
نویسندگان
چکیده
Ferrous and ferric sulphates and (oxy)hydroxides can grow on pyrite surfaces and slow oxidation rates. However, in northern climates, repeated freeze/thaw cycles can cause cracks, channeling and exposure of new surfaces. In the present study, weathering in a repeated freeze/thaw experiment was compared to a regular humidity cell experiment. Introductory results (after 17 weeks) show very small changes in pH for the freeze/thaw system (pH around 5), while pH in reference and humidity cell systems decreased rapidly the first weeks (to around 4). An increase in electrical conductivity, sulphate and major ions was noticed in the
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