ANKOM 200 Series - Manual (Page 20)

Operator’s Manual
pg. 20
Rev C 1/14/15
18. After the third rinse, open the Vessel Lid and remove the Bag Suspender from the Vessel.
19. Remove the bags from the Bag Suspender trays and place them in a 250 ml beaker.
20. With your hands, gently press out excess water from the bags into the
beaker and pour off the water from the beaker.
21. With the bags in a 250 ml beaker, add enough acetone to cover them. Let
the bags soak in acetone for 3 - 5 minutes. Pour off the acetone.
22. With your hands, gently press out excess acetone from the bags into the
beaker and pour off the acetone from the beaker.
23. Remove the bags from the beaker and place them on a wire screen to air-dry.
Hazardous Materials – Do NOT place bags in an oven until all acetone in
the bags has evaporated.
24. Place air-dried bags in the oven and heat at 102°C ± 2° for 2 - 4 hours (depending on the oven).
25. Remove the samples from the oven and place them directly in a Desiccant
Pouch. Flatten the pouch to remove ambient air and zip it tight.
Do NOT use conventional countertop or cabinet desiccators for this
analysis.
26. Allow the samples to cool to room temperature. This should take about 10 - 15 minutes.
27. Remove one filter bag from the Desiccant Pouch. Flatten the pouch to remove ambient air.
To prevent moisture from settling on the filter bags, it is important to keep
ambient air out of the Desiccant Pouch while weighing the bags. This can
be done by holding the pouch flat or zipping it shut after removing filter
bags. Zipping the bags too often can reduce the life of the Desiccant Pouch.
28. Re-weigh the filter bag (W
3
) immediately.
29. Repeat steps 27 and 28 for each filter bag in the Desiccant Pouch.
30. Calculate NDF according to the formula below.
% NDF (as-received basis) = 100 x (W
3
– (W
1
x C
1
))
W
2
Where: W
1
= Bag tare weight
W
2
= Sample weight
W
3
= Dried weight of filter bag with fiber after extraction process
C
1
= Blank bag correction (running average of final oven-dried weight
divided by original blank bag weight)