Basic Study on the Remediation Technology
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double that of the quartz sand. While heating the artificially contaminated soils
in our tests, the colors of the quartz and standard sands did not change when
they were heated to 200°C, but the standard sand became red (clearly observable
with the naked eye) when heated to 300°C.
As Fig. 4 showing the results of powder analysis with X-rays demonstrates, the
color change in the artificially contaminated soil made with heated standard sand
is thought to be a function of the generation of Fe2 0 3 (hereinafter referred to as
~ . . . W ~ .... j ~.J 1-... l.A ~
20.0
25.0
30.0
35.0
40.0
45.0
50.0
55.0
28
Standard sand
Before heating
30.0
35.0
40.0
28
Standard sand heated to 300t
Fig. 4. Results of powder analysis with X~rays