Bmst System; Bmsx System - Grundfos BMS hs Assembly, Installation And Operating Instructions

4.4 BMST system

4.4.1 Before startup
Follow these instructions to ensure correct startup of the BMST
system.
WARNING
Description of hazard
Death or serious personal injury
- Make sure that the pump and the system are fully
vented before startup.
For type, amount and interval of greasing, see the
nameplate on the motor.
1. Check that the power supply is according to the nameplate.
2. Check that the installation corresponds to the diagram.
9 10
8
7
4
6
5 6.1
3
2
1
16
Fig. 25 Example of BMST booster system
Pos. Description
1 Raw-water feed pump
2 Pressure gauge (raw water)
3 Filter
4 Low-pressure switch
5 Flowmeter
6 BMT pump
6.1 BMS hs pump
7 Pressure gauge (BMST outlet pressure)
8 Flowmeter
9 Vent
10 High-pressure switch
11 Pressure-relief valve
12 Membrane filter
13 Permeate
14 Pressure gauge (high-pressure concentrate)
15 Pressure gauge (fresh-water pump)
16 Fresh-water flush pump
14
13
12
14
15
4.4.2 Startup
To start up a BMST system, proceed as follows:
1. Start the raw-water feed pump (1), and check that the inlet
pressure (2) of the pump is higher than 2.0 bar (20 metres
head) and lower than 5.0 bar (50 metres head).
2. Vent the BMT pump (6).
The pump is fully vented when liquid runs out of the vent (9).
3. Start the BMS hs pump (6.1). See section
4. Set the outlet pressure (7) of the pump to the desired value.
5. Check that the inlet pressure (2) of the pump is higher than
2.0 bar (20 metres head) and lower than 5.0 bar (50 metres
head).
6. The system is now ready for operation.
Make sure that the BMS hs pump is dry-run
protected.
Ramp up from 0 to 1700 rpm within three seconds.

4.5 BMSX system

4.5.1 Flow control and balancing
Flow rates and pressures in a typical BMSX system vary slightly
over the life of the system due to temperature variations,
membrane fouling and feed salinity variations. The rotor of the
pressure exchanger is powered by the flow of fluid through the
unit. The speed of the rotor is self-adjusting over the operating
range of the pressure exchanger pump.
4.5.2 Before startup
Follow these instructions to ensure correct startup of the BMSX
system.
WARNING
Description of hazard
Death or serious personal injury
- Make sure that the pump and the system are fully
vented before startup.
1. See section 4.2 BMS hs pump
2. Check that the installation corresponds to the diagram.
A pressure gauge should be installed near each pipe
connection of the PX unit or PX unit array to facilitate
monitoring of PX unit performance.
4.2.2 Startup.
and 4.3 BMS hp pump.