9. Production of solids in a pump-pipeline system
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October 13, 2004 1 oe4625 Dredge Pumps and Slurry Transport Vaclav Matousek Dredge Pumps and Slurry Transport
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Transcript of 9. Production of solids in a pump-pipeline system
October 13, 2004
Vermelding onderdeel organisatie
1
oe4625 Dredge Pumps and Slurry Transport
Vaclav Matousek
Dredge Pumps and Slurry Transport
October 13, 2004 2
9. PRODUCTION OF SOLIDS IN A PUMP-PIPELINE SYSTEM
PRODUCTION RANGE
PRODUCTION LIMITATION BY PIPE LENGTH
PRODUCTION LIMITATION BY PUMP POSITION
Dredge Pumps and Slurry Transport
October 13, 2004 3
Flow Parameters: Production of SolidsThe production of solids is an important parameter from the economic
point of view. It gives the amount of dry solids delivered at the pipeline outlet over a certain time period.
This is defined as the (volumetric) flow rate of solids at the outlet of a slurry pipeline
2 36004s m vdQ D V Cπ
=3m
hour
During a dredging operation the parameters Vm and Cvd are usually measured in a pipeline of known D so that the production of solids given by a solids flow rate can be determined.
Dredge Pumps and Slurry Transport
October 13, 2004 4
Flow Parameters: Production of SolidsThe production of solids is an important parameter from the economic
point of view. It gives the amount of dry solids delivered at the pipeline outlet over a certain time period.
This is defined as the (volumetric) flow rate of solids at the outlet of a slurry pipeline
During a dredging operation the parameters Vm and Cvd are usually measured in a pipeline of known D so that the production of solids given by a solids flow rate can be determined.
s m vd ms f
Q Q C Qρ ρρ ρ
−= =
−
3
secm
m f
Dredge Pumps and Slurry Transport
October 13, 2004 5
PRODUCTION RANGE
OPERATIONAL LIMITS
MAXIMUM ATTAINABLE PRODUCTION
MINIMUM ACCEPTABLE PRODUCTION
Dredge Pumps and Slurry Transport
October 13, 2004 6
MAXIMUM VELOCITY IN THE SYSTEM
( ) 2
2atm vapourd m
Rf f
Vac P P V NPSHg g gρ ρ
−= + −
atm S
f f
P PVacg gρ ρ
−=
Decisive vacuum curve, (Vac)d & vacuum curves of suction pipe, Vac.
Dredge Pumps and Slurry Transport
October 13, 2004 7
EFFECT OF PUMP POSITION ON
OPERATIONAL LIMITS
Dredge Pumps and Slurry Transport
October 13, 2004 8
PRODUCTION RANGE
MAXIMUM ATTAINABLE PRODUCTION
Figure. Production limited by decisive vacuum. Qm-Qs diagram.
Dredge Pumps and Slurry Transport
October 13, 2004 9
PRODUCTION RANGE
OPERATIONAL LIMITS
Decisive vacuum curve & vacuum curves of suction pipe.
Dredge Pumps and Slurry Transport
October 13, 2004 10
PRODUCTION RANGE
MAXIMUM ATTAINABLE PRODUCTION
Figure. Production limited by decisive vacuum. Qm-Qs diagram.
Dredge Pumps and Slurry Transport
October 13, 2004 11
PRODUCTION RANGE
MINIMUM ACCEPTABLE PRODUCTION
Production limited by decisive vacuum and deposition-limit velocity.
Dredge Pumps and Slurry Transport
October 13, 2004 12
PRODUCTION LIMITATIONS
I. Too Short Pipeline: the pump tends to operate outside a normal working range, the pump speed must be lowered to avoid cavitation
II. Pipeline Distance Within a Normal Working Range of a Pump: a pump operates at maximum speed and mixture of maximum attainable density is transported
III. Too Long Pipeline: the pump tends to operate outside a normal working range, the mixture density must be lowered to maintain velocity above the deposition limit in a pipeline
Dredge Pumps and Slurry Transport
October 13, 2004 13
PRODUCTION LIMITATIONS
I. Too Short Pipeline
II. Pipeline Distance Within a Normal Working Range of a Pump
III. Too Long Pipeline
Dredge Pumps and Slurry Transport
October 13, 2004 14
PRODUCTION LIMITATIONS
I. Too Short Pipeline
II. Pipeline Distance Within a Normal Working Range of a Pump
III. Too Long Pipeline
Dredge Pumps and Slurry Transport
