Page 250 - Reservoir Formation Damage

230 Reservoir Formation Damage

to a plateau was an indication of simultaneous pore surface deposition
and pore throat plugging, and indicated by "S and P" in Table 10-2. Filter
cake deposition was indicated by "FC" in Table 10-2.
Gruesbeck and Collins carried out experiments under conditions favor-
able for simultaneous surface deposition and pore throat plugging. For
this purpose, suspensions of class beads were injected into columns of
clean sand packs. The effluent glass beads concentration, pressure dif-
ference across the sand pack, and cumulative class bead deposit in the
sand pack were measured as a function of the pore volume of suspension
of glass beads injected at constant rates. The experimental data are
presented in Figure 10-25. Next, they have solved their model equations,
Eqs. 10-121, 111, 112, 114, 115, 116, numerically by assuming trial

5
Q. ._
4
§5
3 0.5 CM/SEC
2 1.5 CM/SEC
cc < 1
O- CC
0
0.20
. 0.16
o
£2
£0.12
| 0.08
>
0.04
0.00
100 200 300 400 500
PORE VOLUMES
Figure 10-25. Deposition and entrainment of 5-10 mm diameter glass beads
in a porous medium of 15.24 cm pack of 250-297 mm diameter sand grains
4
for 9.5 x 10" injection suspension concentration (after Gruesbeck and Collins,
©1982 SPE; reprinted by permission of the Society of Petroleum Engineers).