Soil cleaning from PAH
Project in collaboration with GKSS-Forschungszentrum
Geesthacht GmbH .
Polluted soil with PAH is extremally poisonous for living organisms
and human lifes. Such polluted soil remains, e.g., after militar or industrial
activities. For this reason, a reactor for cleaning of dust was constructed
in GKSS (see figure below). Dust consists 30 % of dry phase (soil and PAH)
and 70 % water. The dry phase contains 0.1-10 % oil and 0.5 % PAH.
|The characteristic distribution of diameter of soil particles. Measured
by laser scattering technique using HORIBA LA-910. The blue curve is distribution
of to soil particles before entering into the reactor, while red - after
leaving the reactor tube. Mean diameter of soil before reactor is 17.8
and after - only 6.6 mm. We can interpret it
as soil particles disintegrates into parts during evaporation in the reactor.
|Some basic data of PAH can be obtained from .
The PAH molecules consist of or more benzole rings. In general, the boiling
temperature is higher for molecules with higher molecular weight. The cleaning
efficiency for PAH with higher boiling temperature is much lower. The melting
temperature for more masive PAH molecules is higher than of boiling temperature
Page compiled by Vilnis Frishfelds.
Last update: 03.08.00.
|Spraying process. Soil particle is coated with layer of water. Water
starts to evaporate at the entering of the reactor. Therefore, the radius
of the dust droplet monotonously decreases. Characteristic evaporation
time for particles with 100 mm diameter is approximately
a second. The evaporation time decreases parabolicaly for particles with