BAKER HUGHES - Drilling Fluids Reference Manual

Water Based Drilling Fluids
Table 3-31
Component
Return permeability on Berea Sandstone for 20% NaCl, 12 lb/gal
PERFORMAX
Concentration
NaOH, lbm/bbl 0.4
NEW-DRILL ® PLUS, lbm/bbl 0.4
XAN-PLEX ® D, lbm/bbl 0.5
BIO-LOSE ® , lbm/bbl 2
MAX-TROL , lbm/bbl 8
MAX-PLEX , lbm/bbl 6
MAX-SHIELD , volume % 3
ALL-TEMP ® , lbm/bbl 1
NaCl, lbm/bbl 61
MIL-BAR ® , lbm/bbl 146
MAX-PLEX in API filtrate, cm 3 /30 min 3.5
% Return permeability, 200°F, 500 psi 97
MAX-PLEX or ALPLEX ® Determination by Fluoride Electrode
The concentration of MAX-PLEX in the filtrate can be determined by using a fluoride selective
electrode procedure. This method indirectly determines the MAX-PLEX concentration by
converting aluminate to aluminum cations,
which then react with fluoride anions to produce
a mixture of aluminum fluoride species. The
fluoride ion excess is correlated to the available
MAX-PLEX concentration by means of a chart.
An FSE probe must be used to accurately
determine the “actual” concentration of MAX-
PLEX in the system because the material is
depleted (consumed) during drilling. The graph
to the right shows a comparison of MAX-PLEX
concentration using a mass balance vs. FSE
method of determining the available
concentration of MAX-PLEX in the system.
This example clearly shows that the “actual” concentration of available aluminate in MAX-PLEX
(or ALPLEX) cannot be accurately determined using a mass balance approach to determine
product concentration. The only accurate method to determine available MAX-PLEX (ALPLEX)
is to use the FSE probe.
Reference Manual
Baker Hughes Drilling Fluids
3-100 Revised 2006