Page 168 - Percolation Models for Transport in Porous Media With

9.3 EXPERIMENT AND THEORETICAL RESULTS 165

K
K. 0 . z
1
-I
;

z

·o to zo .,, w·h/•g
Figure 62: The energy input dependence of the irreversible change of the per-
meability: 1, 2- results given by measurements taken after electric treatment of
a sandy-argillaceous medium with impulse and alternating current; 3- results of
the theoretical calculations

value of w was increased, and the third and the fourth stages were conducted for
the first and the second tubes.
The results of electric treatment showed that for w :$ 0.002 kilowatt-hours per
kilogram, irreversible changes of permeability of the first and the second tubes were
not observed. The production rate of the third tube dropped insignificantly {10%).
For w = 0.005 kilowatt-hours per kilogram, electric treatment with alternating
current did not yield any change in the production rate. At the same time, electric
treatment with impulse current 1 hour after it was terminated made the production
rate grow by 25% (K/Ko = 1.25). With the flow that followed (stage 4), after 3
days the increase of the production rate reached 50%. For w = 0.01 kilowatt-hours
per kilogram, immediately after the electric treatment the production rate in the
first two tubes increased; however, 5 days later the augmentation of the production
rate for the treatment with alternating current made up 50% and impulse current,
120%. For w = 0.02 kilowatt-hours per kilogram, after the electric treatment the
production rate in tubes 1 and 2 fell almost down to zero {3- 5% from its initial
value). However 2 hours after the treatment the augmentation of the production
rate reached 100% for tube 1 and 150% for tube 2 (K / K 0 = 2.5). A day later
the production rates of both tubes grew. For the first tube, the increase reached
130% (K/Ko = 2.3) and for the second tube, 470% (K/Ko = 5.7). Three days
later the production rate of the first tube remained still greater than its initial
value by 130%, while for the second tube, the augmentation of K decreased to
280% (K/Ko = 3.8). Further on (for about 5 days) the production rate of the
tubes remained almost steady. Thus for w = 0.02 kilowatt-hours per kilogram, a
sharp decrease {almost down to zero} of the production rate immediately after the
electric treatment and its substantial increase (K/Ko = 3 + 5} 3- 5 days later,
was observed.