Westfalia OSD 6-91-067, Instruction Manual

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Westfalia Separator
58
Mineraloil Systems GmbH
2058-9001-101 / 0506
3.5 Setting the separation time
When using time-dependent automatic control programs, accurate setting of the
separation time (time between ejection cycles) is only possible if the throughput
capacity and solids loading in the feed remain constant. If this is not the case, it
may be necessary to correct the settings during operation.
The separating time depends on
•
the preselected operating mode (partial or total ejection mode),
•
the solids loading in the feed,
•
the consistency of the solids,
•
the effective solids space volume in the bowl,
•
the separator throughput.
Given constant conditions, the separating time can be determined by calcula-
tion.
The following times have proven appropriate in practice (examples):
Product Total ejection Partial ejection
HFO 1 h to max. 2 h 0,5 h to max. 1 h
MDO 2 h 1 h
LO mild 2 h 1 h
LO HD 1 h to max. 2 h 0,5 h to max. 1 h
3.5.1 Mathematical calculation
Example for mathematical calculation of the separating time:
Given: Solids content
(1)
p = 0.05 %
Solids holding space volume V = 0.9 l
Solids holding space given 75 % utilisation V' = 0.6 l
Throughput capacity
(1)
V
o
= 1 000 l/h
Wanted: Separating time t = ? min
The separating time to be set is calculated as follows:
V’ 0.6
t = ——— • 60 • 100 = —————— • 6 000 = 72 min = 1.2 h
V
°
• p
1 000 • 0.05
(1)
Solids content and throughput capacity must be determined on site or taken from
the order specification.