Page 170 - Percolation Models for Transport in Porous Media With

Chapter 10

Changing Well Production

with Electric Treatment

10.1 Calculation of Change in Well Production

after Electric Treatment

The relationships describing the changes in the permeability and the electric con-
ductivity of a medium in time for a given amplitude of the electric field intensity
(§8.2, 8.4} allow to determine the change of the well production after electric
treatment (86).
The result of the electric treatment depends substantially on the diagram of
electric energy supply to the medium. Three most widespread diagrams are pre-
sented in fig. 63. Further calculations are carried out for diagram III, and the
conversion factors are given for the other two.
In this diagram, the first power electrode is a casing column with a metal
filter (the filter column) with the total length Hw. The second power electrode
is at a distance of H,, much greater than the depth of the well, and is grounded.
The equation describing the steady state current flow in the general case has the
following form,

div j = 0 (10.1)
j='EE {10.2}

E = -'V</>e (10.3}

Here j is the current density vector, E(r, t) is the field intensity vector, which
depends on the radius-vector r and time t, 4>e is the electric field potential and E
is the electric conductivity of the medium.

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