OFITE, 11302 Steeplecrest Dr., Houston, TX 77065 USA / Tel: 832-320-7300 / Fax: 713-880-9886 / www.ofite.com
30
Data
Filtrate Volume
The HTHP filter press has a filtration area of 3.55 in
2
(22.9 cm
2
). This is half
the area of a standard filtration test, which is 7.1 in
2
(45.8 cm
2
). To compare
the results of this test to a standard filtration test, double the total filtrate vol
-
ume collected for the full 30 minutes.
V
S
= 2 (V
30
)
Spurt Loss (Optional)
Spurt Loss is the amount of filtrate collected before the filter cake has had a
chance to form and is expressed in millimeters. To calculate the spurt loss,
use the following equation:
V
1
= 2 [V
7.5
- (V
30
-
V
7.5
)] = 2 (2V
7.5
- V
30
) = 4V
7.5
- 2V
30
Where:
V
s
= Standard Filtrate Volume (mL)
V
1
= Spurt Loss
V
7.5
= Filtrate volume in milliliters collected after 7.5 minutes (doubled)
V
30
= Filtrate volume in milliliters collected after 30 minutes (doubled)
Filter Cake
Wash the filter cake on the paper with a gentle stream of water. Measure and
report the thickness of the filter cake to the nearest
1⁄32
" (0.8 mm). A ruler with
the “zero mark” at the very edge of the ruler is useful here. Cake descriptions
may be subjective and such notations such as hard, soft, rubbery, and fine,
etc. convey adequate information on cake quality.
