Danfoss MPE 70 User manual

Operating guide
Energy Recovery Device
MPE 70
Installation, Operation and
Maintenance Manual
hpp.danfoss.com

Operating guide | MPE 70
2180R9426 | AQ367027814446en-000801 | IOM MPE 70 | 08.2022
Table of Contents 1 Validity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
2 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
2.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.2 Target group. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.3 Symbols. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.4 Manufacturer and customer service address . . . . . . . . . . . . . . . . . . . . . . . 5
2.5 Country specic information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.5.1 United Kingdom . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.6 Additional technical documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3 Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.2 Intended use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.3 Application range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.4 Preferred system design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.5 Initial start-up and settings of safety equipment . . . . . . . . . . . . . . . . . . . . 8
3.6 Over-pressurisation caused by low pressure isolation. . . . . . . . . . . . . . . . . . 8
4 Arrival inspection, handling and storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
4.1 Arrival inspection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
4.2 Return to the supplier. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
4.3 Transport and Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
4.4 Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
5 Technical data and design details . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
5.1 Design details . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
5.2 Sound level of the MPE 70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
5.3 Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
5.4 Temperature and corrosion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
5.5 Dimensions and weights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
5.6 Electrical motor data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
5.7 How does the MPE 70 work?. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
6 Operation and Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
6.1 Initial start-up and ushing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
6.2 Air bubbles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
6.3 Start-up sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
6.4 Shut-down sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
6.5 High pressure remains after shutdown . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
6.6 CIP or membrane cleaning. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
6.7 Flushing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
6.8 Seawater quality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
6.8.1 Pre-ltration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
6.8.2Chemicals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16

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7 On-site installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
7.1 Design details . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
7.2 Assembly MPE 70 to electric motor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
7.3 Danfoss Oers rail and Bracket solution . . . . . . . . . . . . . . . . . . . . . . . . . . 17
7.4 Orientation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
7.5 Piping and joints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
7.6 Accessibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
7.7 Motor and frequency converter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
7.7.1 Electric motor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
7.7.2 Starting torque for the MPE 70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
7.7.3 Frequency converter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
8 Commissioning, start-up and shutdown . . . . . . . . . . . . . . . . . . . . . . . .19
8.1 Safety regulations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
8.2 Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
8.3 Commissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
9 Service/Maintenance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
9.1 Safety regulations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
9.2 Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
9.3 Maintenance schedule . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
9.4 Recommended service intervals for MPE 70 . . . . . . . . . . . . . . . . . . . . . . .21
9.5 Recommended service for electric motor . . . . . . . . . . . . . . . . . . . . . . . . .21
10 Trouble-shooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
10.1 Safety regulations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
11 Appendix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
11 Appendices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
11.1 Data sheet MPE 70 (AI358154451639en-000401)). . . . . . . . . . . . . . . . . . . . .25
11.2 Instruction (AN362429033229en-000201) . . . . . . . . . . . . . . . . . . . . . . . . .39
11.3 Design guide Pipe connections (180R9367) . . . . . . . . . . . . . . . . . . . . . . . .51
11.4 MPE 70 part list (AX361839752024en-000301). . . . . . . . . . . . . . . . . . . . . . .53
11.5 Operating- and maintenance instruction, electric motor (180R9230) . . . . . . . .59

Operating guide | MPE 70
4180R9426 | AQ367027814446en-000801 | IOM MPE 70 | 08.2022
Document information and copyright
Installation, Operation and Maintenance
Manual.
Danfoss can accept no responsibility for
possible errors in the manual and
instructions. Danfoss reserves the right
to alter its products without notice. This
also applies to products already on order
provided that such alterations can be made
without subsequential changes being
necessary in specications already agreed.
All rights reserved. Contents provided
herein must neither be distributed, copied,
reproduced, edited or processed for any
other purpose, nor otherwise translated or
published without Danfoss’express written
consent.
Validity
This manual is valid for MPE 70
Description Code no. Serial no.
MPE 70 without
motor 180F7070 XXXXXX01-XXX
MPE 70 (IEC motor) 180F7066 XXXXXX01-XXX
The serial number is referring to the Serial
no. on the product label. The digits shown
(01) indicate the version number of the
pump.
This document is only valid for MPE version
1 and upwards.
1. Validity
ERD
Type MPE 70
Code no. 180F7070
Serial no. XXXXXX01-XXX
MADE IN DENMARK
Danfoss A/S, 6430 Nordborg, Denmark

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2. Introduction 2.1 General
MPE 70 is manufactured by Danfoss A/S, and
is sold and marketed by a net of authorised
distributors world wide.
This manual contains the necessary instruc-
tions for the installation, operation and
service of the MPE 70.
All personnel who are responsible
for the operation and maintenance of the
MPE 70 unit must read and fully unders-
tand these instructions, especially the
section “Safety” before:
• Transporting of the MPE 70 unit.
• Lifting the unit.
• Installing the MPE 70 unit on a frame.
• Connecting the MPE 70 unit to the uid
system.
• Connecting the electrical motor and
instrumentation.
• Commissioning the unit.
• Servicing the MPE 70 unit, mechanics
and electrics.
• Decommissioning the MPE 70 unit.
Ensure that these instructions are
always readily available to all personnel
concerned.
2.2 Target group
This manual is intended for use by
personnel with qualied training and
experience in the operation and
maintenance of a Sea Water Reverse
Osmosis (SWRO) or Brackish Water Reverse
Osmosis (BWRO) system.
2.3 Symbols
Indicates something to be noted by
the reader.
Indicates a situation which will or
could result in damage to the MPE 70
and its function.
Indicates a situation which will or
could result in personal injury and/or
damage to the MPE 70.
Electrical hazard. Indicates a
high-voltage warning
Safety glasses required
Hearing protection required
Safety shoes required
Safety helmet required
2.4 Manufacturer and customer service
Danfoss A/S
High Pressure Pumps
DK-6430 Nordborg, Denmark
Telephone: [phone]
Email: [e-mail]
Homepage: hpp.danfoss.com
2.5 Country specic information
2.5.1 United Kingdom
UK importer:
Danfoss Ltd.
22 Wycombe End
HP9 1NB Beaconseld
United Kingdom

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2.6 Additional technical documents
Below documents are not present in this Operating guide. Please contact Danfoss.
Document name Content
Service guide: “MPE 70 Disassembling and
assembling”
Description of how to disassemble and as-
semble the MPE 70
Guide line: “P and ID review sheet” Detailed description about the need for
each individual component in the preferred
P&ID
Quick guide for FC51 ; “MG02BC02” Description on how to setup Danfoss
frequency controler type FC 51

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3. Safety 3.1 General
The MPE 70 must not be used for other
purposes than those recommended and
specied without rst consulting your local
MPE 70 distributor.
This manual must be read and completely
understood by the responsible specialist
personnel prior to installation and commis-
sioning.
Use of this manual does not relieve opera-
tion and maintenance personnel of the
responsibility of applying normal good
judgment in the operation and care of this
product and its components.
This manual must be available to all person-
nel concerned at the site at all time.
An MPE 70 must always be installed and
used in accordance with existing national
and local sanitary and safety regulations
and laws. It is the responsibility of the safety
ocer or the chief operator to assure com-
pliance with all local regulations that are not
taken into account in this manual.
The MPE 70 is a rotating machine that typi-
cally operates at high pressure.
Always wear suitable safety and lifting
equipment when handling the MPE 70.
• Bolt the MPE 70 properly to the frame
before start-up to avoid personal
injury and/or damage to the MPE 70.
• The pipe connections to the MPE 70
must be stress-free mounted, securely
fastened to the MPE 70 and well
supported. Improper installation will
or could result in personal injury
and/or damage to the MPE 70.
• Proper installation and care of
shutdown devices and over-pressure
protection equipment is essential.
• All electrical installation work must be
carried out by authorised personnel in
accordance with EN60204-1 and/or
local regulations.
• Install a lockable circuit breaker to
avoid inadvertent starting. Protect the
motor and other electrical equipment
from overloads with suitable
equipment.
• The electric motors must be supplied
with adequate cooling ventilation.
• Improper installation can cause fatal
injuries.
• The MPE 70 must not operate outside
the application range.
• Make sure that the pressure is
released from the MPE 70 before the
MPE 70 is disconnected from any pipe
connections.
• Before intervening in the
MPE 70/system, the power must be
shut o and the starting device must
be locked. When intervening in the
MPE 70 unit, follow the instructions
for Service/Maintenance, chapter 8.
• A failure not to follow the instructions
can result in personal injury and/or
damage to the MPE 70. It will also
invalidate the warranty.
• The MPE 70 must never run dry. Dry
running produces heat and will cause
damage to internal parts.
• If the MPE 70 does not function
satisfactorily, contact your local MPE
70 distributor.
Use of this manual does not relieve
operation and maintenance personnel
of the responsibility of applying normal
good judgment in the operation and
care of this product.

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3.2 Intended use
The MPE 70 is designed for use as energy
recovery device in Sea Water Reverse
Osmosis (SWRO) or Brackish Water Reverse
Osmosis (BWRO) system.
The MPE 70 must not be used for other
purposes than recommended and quoted
for without consulting your local MPE 70
distributor.
3.3 Application range
For application range see data sheet
“MPE 70 Pressure exchanger” available in ap-
pendix 11.1.
Applications not suitable for the MPE
70 can cause damages to the
MPE 70 unit, with risk of personal
injury.
3.4 Preferred system design
Danfoss recommends building systems with
a high degree of safety. Our preferred
system design can be found in the data
sheet “MPE 70 Pressure exchanger” in ap-
pendix 11.1.
• It is always the system builders’ re-
sponsibility to ensure that the system
design does not cause any form of
hazard and are adapted to local regu-
lations.
• Proper installation and care of
shutdown devices and over-pressure
protection equipment is essential.
3.5 Initial start-up and settings of safety
equipment
To prevent such over-pressurisation,
appropriate relief valves should be
used or procedures should be
implemented to safeguard the HP
lines and instrumentations in the
RO system.
The system designer is responsible to
design the equipment according to the
local regulations where the equipment
is running. According to PED 2014/68/
EU a risk assessment must be made to
identify and evaluate hazards which
apply to his equipment on account of
pressure.
Where under reasonable foreseeable
conditions, the allowable limits could
be exceeded, the pressure equipment
must be tted with, or provision made
for tting of a suitable protective
device.
3.6 Over-pressurisation caused by low
pressure isolation
If both LP In and LP Out lines of the MPE70 is
blocked and the MPE 70 is exposed to
high-pressure, there is a risk that the LP
piping could be damaged by over-pressuri-
sation.
If positive displacement pumps are
used be aware they can build up
pressure exceeding the mechanical
strength of the membrane vessels,
pipes and other accessories. The pres-
sure rise can be fast and may exceed
the response time for electrical safety
equipment, like pressure switch and
control loop.
To prevent such over-pressurisation,
appropriate relief valves should be
installed in the LP side or procedures
should be implemented to assure that
the HP of the MPE 70 is depressurised
prior to the isolation of the LP side.

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4. Arrival inspection,
handling and storage
4.1 Arrival inspection
The MPE 70 is packed in a wooden box. The
MPE 70 ports connector are protected by
plastic caps that protect the MPE 70 against
dust and particles. Do not remove the caps
before the system have been ushed and
the MPE 70 can be installed.
Remove all packing materials immediately
after delivery. Immediately check the
shipment for damage on arrival and make
sure that the name plate/type designation is
in accordance with the packing slip and your
order.
In case of damage and/or missing parts, a
report should be drawn up and presented
to the carrier at once.
The identication label on the MPE 70 states
the specic type, the serial number and the
code number of the MPE 70; see g. below.
The last three digits of the Serial No. indicate
the week and year of production.
4.2 Return to the supplier
Flush the MPE 70 with clean water. Drain the
MPE 70 and plug the port connections with a
cap/cover.
Pack the MPE 70 into a suitable container
and make sure that it is suitably fastened to
the container.
4.3 Transport and Handling
• Personnel involved in lifting and
transportation of the equipment must be
trained in proper handling and safety
procedures.
• Observe the local regulations regarding
lifting.
• Use suitable, permitted lifting equipment.
• Be aware of individuals located in the
operation area while lifting the
component.
The weight of the MPE 70 including electric
motor can be found in the data sheet.
All parts weighing more than 20 kg (44 lb)
must be lifted using lifting slings and suit-
able lifting devices, e.g. an overhead crane
or fork lift.
Do not use connections/nozzles for lifting.
Do not use only one sling! Make sure that
the load is balanced before attempting the
lift.
ERD
Type MPE 70
Code no. 180F7070
Serial no. XXXXXX01-XXX
MADE IN DENMARK
Danfoss A/S, 6430 Nordborg, Denmark
Please coordinate the shipment with your
local authorized distributor or contact
Danfoss direct to obtain a return shipping
address.
When lifting the ERD use the lifting eyes.

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Incorrect lifting can result in personal
injury and/or damage of the unit.
4.4 Storage
Each MPE 70 is tested in demineralized
water before shipment. When tested the
MPE 70 is emptied and “plugged”, this will
prevent frost damages.
The storage temperature is is:
-40 °C to +70 °C (-40°F to 158 °F) –
provided that the MPE 70 is drained of uid
and stored “plugged”.
Frost protection is required if the MPE 70 is
not completely drained of uids at tempera-
tures below 1 °C
Storage of MPE 70 that have been in opera-
tion:
For shorter periods of storage ush the MPE
70 with permeate and store.
For long term storage (more than 2 months)
Danfoss recommends to clean any biologi-
cal growth of the surfaces. Store the Pres-
sure Exchanger dry without water inside.
Danfoss recommends using DOWFROST
from DOW Chemical Company
or Chillsafe mono propylene glycol from
Arco Chemical Company.
For further information on anti-freeze me-
dia, please contact Danfoss High Pressure
Pumps.
• The MPE 70 is delivered
frost-protected from the factory.
• Only remove caps from the openings
of the MPE 70 at the time of installa
tion.
4.5 Outdoor Storage
For outdoor storage cover the MPE 70
(set) with waterproof material.
When the MPE 70 is mounted with an
electric motor and lifted horizontal it must
be lifted in the lifting eye on the MPE 70.
Some motors have specic lifting eyes -
these should only be used for lifting the mo-
tor. For more information on lifting please
read the installation guide MPE 70 ERD
Installation instruction.
Do not use connections/nozzles for lift-
ing!
For more information see “MPE 70 Installa-
tion instructions” in appendix 11.2.
Lifting the MPE 70 with electric motor
(vertical):
Lift the MPE 70 unit with suitable lifting eyes
mounted in the ange as shown on the pic-
ture. Suitable lifting eys in part of the toolkit
180F4177.

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5.1 Design details5. Technical data and
design details
5.2 Sound level of the MPE 70
The A-weighted sound pressure level @ 1m,
LPA, 1M is for the MPE 70 including the MPE 70
motor.
Measurement are according to EN ISO
3744:2010. The test is made under following
conditions:
1. MPE 70 and electrical motor
mounted together.
2. LP In pressure is 2 barg (29 psig)
3. Rotation speed is max. rpm
4. System pressure is max. allowable
working pressure.
Inuences
The structural noise may aect the noise
level from the MPE 70 system. The sound
level is therefor only given for the MPE 70 in-
cluding the MPE 70 motor. The Sound pres-
sure level can be found in data sheet MPE 70
Pressurre exchanger in appendix 11.1.Struc-
tural noise may aect the noise level.
Use multiple exible Victaulic® couplings on
the hard piping.
The noise level is inuenced by:
• The speed of the MPE 70. High speed
creates more noise than low speed.
• Higher pressure provides higher sound
level. For sound levels in specic duty
point please contact Danfoss High pres-
sure Pumps.
1: 3” Victaulic connections
2: Shaft
3: Low pressure shaft seal
4: Port ange
5: Valve plate
6: Cylinder barrel
7: Port plate (brine)
8: Port plate (feed)
9: Motor ange

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In order to minimise the risk of crevice
corrosion, always ush the MPE 70
according to the specied start/stop
procedure.
5.3 Materials
All critical parts of the MPE 70 are made of
super-duplex 1.4410/UN S32750/1.4462/
UN S32205/S31803 or the like.
Non-critical parts that are not in contact
with sea water are made of AISI 316.
The shaft to the electrical motor is sealed by
a standardised mechanical seal.
5.4 Temperature and corrosion
The chart below illustrates the corrosive
resistance of dierent types of stainless steel
related to NaCl concentration and
temperature.
Depending on the NaCl concentration, the
uid temperature must be between: +2 °C to
+50 °C (+35.6 °F to 122 °F).
5.5 Dimensions and weights
For dimensions and weights please refer to
the MPE 70 data sheet. See appendix 11.1.
5.6 Electrical motor data
See data sheet in appendix 11.1 and
Operating and Maintenance
instructions, electric motor in
appendix 11.5.
316L
Super Duplex
80
ºC
70
60
50
40
30
20
100
160 1600
1000
16000
10 000
160000
100 000 CI -
ppm
NaCI
ppm
Duplex

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5.7 How does the MPE 70 work?
The gure below shows the princip in the
MPE 70.
The MPE 70 is a rotating isobaric pressure
exchanger. The device is transferring the
pressure in the Reverse osmosis brine reject
stream to a seawater feed line stream that is
reused in the RO system.
The sketch below shows how the energy is
exchanged.
Skecth showing the principle of MPE pressure exchange
The MPE 70 rotor is rotated by an electric
motor. The rotor spins between two end
covers.
Pressure energy is transferred directly from
the high pressure stream to the low pressure
stream in the ducts of the rotor. Some uid
that remains in the ducts serves as a barrier
that inhibits mixing between the streams.
The speed is controlled by the electric
mothe speed set-point is recommended
to be proportional to the ow given by the
booster pump.the ow and speed will be
proportional. For further ow characteristic
see data sheet section 5.1- MPE ow Curve.

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Loop Nº Control reference Position
number Control element Position number Set points
1Pressure transmitter 21 Seawater intake pumps -2 barg
(29 psig)
2 Low pressure inlet ow 12 Control valve 15 Design ow
3 Booster pump ow 29 Booster pump 30 Design ow
4 Booster pump ow 29 MPE 70 11 Design ow
5Fresh water permeate
ush 12 Control valve 15 Design ow for ushing
6MPE 70 ushing 12 Seawater intake pumps Design ow
7MPE 70 ushing 29 Booster pump & MPE 70 30 & 11 Design fow
8MPE 70 ushing 12 Control valve 15 Design ow
It is recommended to disconnect all connec-
tions to the MPE 70 and to thoroughly ush
the piping before the MPE 70 is connected
to the inlet and outlet connections.
Prior to the initial start-up, all piping
associated with the MPE 70 unit should be
thoroughly ushed to assure that no
impurities enter the MPE 70. Inadequate
pre-ushing will strongly aect the life
of the MPE 70 and may lead to its eventual
breakdown.
It is essential that the water used for
the nal pre-ush is pre-ltered to a
level described in chapter 6.8.
M
HP in
HP out
M
Permeate
F
F
F
MPE 70
M
HP in
HP out
VFD
6
19
17
8
9
27
15
1011
11
12
Drain
4
18
2
M
4
18
LP in
*
*
Second stage lter:
If recommended housing design and cartridges are not used, a second stage lter is
required
1
21
2
PS
PI
PS
PI
14
PI
PI
PI
PI
3
22
22
PS
24
23
25
25
26
26
CIP
28
F
29
M
30
31
MPE 70
VFD
VFD
VFD
VFD
23
LP out
1. Flowmeter
2. Pressure indicator
3. Pressure Switch
4. Motor HP pump
5. Pressure indicator
6. Safety valve
7. Plug valve
8. Venting valve
9. Plug valve
10. Pressure indicator
11. MPE 70
12. Flowmeter
13. Fresh water permeate ush
14. Pressure indicator
15. Controll valve
16. Membrane
17. Flowmeter
18. Check valve
19. Full ow cleaning/CIP
20. Frequency converter
21. Pressure indicator
22. Frequency converter
23. Frequency converter
24. Pressure Indicator
25. HP Hose
26. LP Hose
27. Plug valve
28. Plug valve
29. Flowmeter
30. Booster pump
31. Media lter
32. 5 µm Nominal Melt blown lter
33 Filter 10 micron ABS
13
21
7
5
20
16
32
31
33
1. Flowmeter
2. Pressure indicator
3. Pressure Switch
4. Motor HP pump
5. Pressure switch
6. Safety valve
7. Plug valve
8. Venting valve
9. Plug valve
10. Pressure indicator
11. MPE 70
12. Flowmeter
13. Fresh water permeate ush
14. Pressure indicator
15. Flow control valve
16. Membrane
17. Flowmeter
18. Check valve
19. Full ow cleaning/CIP
20. Frequency converter
21. Pressure indicator
22. Frequency converter
23. Frequency converter
24. Pressure switch
25. HP Hose
26. LP Hose
27. Plug valve
28. Plug valve
29. Flowmeter
30. Booster pump
31. Media lter
32.5 μm Nominal Melt blown lter
33 Filter 10 micron ABS
6. Operation and
Controls
For the startup and shutdown of the MPE
70 the following steps should be followed
for safe operation. The Preferred P&ID and
control loops will be used in the explana-
tions below.
6.1 Initial start-up and ushing Strainers do not eliminate the need for
thoroughly pipe ushing before commis-
sioning.
For more information on the importance
of proper ltration, please consult our
publication data sheet, “Filter solutions for
high-pressure pumps and ERDs”, which also
will provide you with an explanation of ltra-
tion denitions and guidance on
how to select the right lter.
Preferred P&ID
Control loops

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6.5 High pressure remains after
shutdown
The HP line of the RO system can remain
pressurised for a long time after shutdown.
If more rapid system depressurisation is re-
quired, the system should be bled through a
suitable valve.
Always check the pressure in the
high-pressure lines before making
service in the HP lines or pressurised
equipment.
6.6 CIP or membrane cleaning
During CIP cleaning the ush water coming
out of the membranes may consist of a large
amount of suspended inorganic
particles. It is important to assure that
these particles must not enter the
MPE 70. After CIP Cleaning the system
should be ushed.
6.2 Air bubbles
Large bubbles in a pressurised RO system
can result in damage to piping and
equipment. All air must be bleed from both
the LP and HP before the RO system is
pressurised. Special consideration should
also be given to air bubbles in feed ow,
continuously fed into the HP pump and MPE
70 could cause increased wear.
Following the start sequence of the seawater
intake pumps water must be ushed though
valves and/or brine outlet valves to ensure
constant water ow with no air or particles
entering the RO system.
Booster pumps will be started rst fol-
lowed by the MPE 70 and then the high
pressure pumps (always in that order).
The control valve Pos 15 will open slowly.
Control loop no. 2 is activated to reach the
setpoint value of the design ow. The ow
will be read in owmeter (12). During this the
system bleed valves can remain open.
The Booster pumps is started by the con-
trol loop no. 3. Once all return ows from
Booster pumps have been stabilized and all
the air have been removed, the bleed valves
can be closed and the MPE 70 will be started
through control loop no. 4. During this the
the system bleed valves remain open until
system have been bled.
When the bleed valves have been closed
the high Pressure pump can be started and
the recovery rate can be conrmed by the
owmeters as described:
The recovery rate can be calculated by the
permeate owmeter Pos 17 and the ow
going into the Membrane. The ow to the
membranes can be calculated from the two
owmeters pos 1 and pos 29.
Recovery Rate = (17) / (1+29)
6.3 Start-up sequence
6.4 Shut-down sequence
When the high-pressure pump is shut
down the shutdown sequence starts. When
the high-pressure pump ow measured
at owmeter (1), is lower than a designed
ow value. The Booster pump can be shut
down once the osmotic pressure have been
reached. The MPE 70 will shutdown after the
booster pump.
After the Booster pump and the MPE 70
have been shut down the seawater intake
pumps can be turned o.

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6.7 Flushing
RO membranes require periodic ushing to
limit biological fouling.
There are two types of ushing: feed water
(Seawater) ush and fresh water (Permeate)
ush.
Regardless of the ush water used, the water
must be pre-ltered to the level described in
chapter 6.8. All parts of the MPE 70 must be
ushed, i.e. LP- and HP ow channels.
It is required to ush with permeate:
• After chemical treatment
• For stops lasting more than 1 day the
MPE 70 must be rotated during
permeate ush
• Before long time shut down
It is required to ush with fresh sea water
prior to every shut down , to remove brine in
the MPE70.
Operating at low pressure should be
limited. Operating at low pressure causes
cavitation but is not critical, it is not
recommended to operate at this state for
longer than 30 min.
Failing to ush the MPE 70 with fresh
water before extended shutdowns
may result in extensive biological
growth and cause corrosion in the
MPE 70 and other equipment in the
RO system.
6.8 Seawater quality
6.8.1 Pre-ltration
It is important that the incoming water is
ltered according to the specication given
in the data sheet appendix 11.1 to assure
optimum service life. A true graded density
melt-blown depth lter cartridge is recom-
mended. Poor pre-ltration of the feed
water will result in reduced service life of the
MPE 70.
The MPE 70 may request a dierent
pre-lter of the seawater than the HP
pump and other components in the
RO system.
It is important to use a proper lter
housing that allows a good seal
between housing and lter cartridge.
If there is a high risk of water by-pass it
is recommended to use a second stage
lter solution.
As the various lters on the market
dier greatly, Danfoss High Pressure
Pumps recommends using cartridges
with consistent, reliable performance
and high eciency, in which bres are
blown continuously onto a central
support core.
Danfoss High Pressure Pumps does not
recommend cartridges requiring any
type of binders or resins.
For more information on the importance
of proper ltration, please consult our
data sheet “Filter solutions for high-pressure
pumps and ERDs”, which also will provide
you with an explanation of ltration deni-
tions and guidance on how to select the
right lter.
6.8.2 Chemicals
The MPE 70 can be ushed with biocide
like the membranes. The biocide must be
compatible with the materials used in the
MPE 70. MPE 70 material can be found in the
parts list, appendix 11.4.

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7.1 Design details
For safety instruction see chapter 3.
7. On-site installation 1: MPE 70
2: Motor
3: Bell housing
4: Flexible coupling
5: Support bracket
6: Rail
The gure above illustrates the major MPE
70 components.
7.4 Orientation
The MPE 70 must be mounted vertically.
When mounted vertically, the electric motor
must be placed above the MPE 70.
7.5 Piping and joints
Hard piping to the MPE 70 must be properly
aligned to avoid stress on the MPE 70 port con-
nections. Don’t use the MPE 70 as a strain for
hard piping.
An unlocked bolt can result in
personal injury and/or damage to the
MPE 70
Misalignment between MPE and
Manifold design may cause stress
and/or damage to the victaulic con-
nection. See guideline “pipe connec-
tion” 180R9367
7.3 Danfoss oers rail and bracket solu-
tion
Danfoss oers rail and bracket solution
for vertical installation. The rail should be
mounted on a steel frame. The base frame
itself must be aligned to avoid bending
caused by bolting to an uneven foundation.
time.
See installation guide for further info.
7.6 Accessibility
With respect to the service and replacement
of the complete MPE 70 unit, it is
recommended to maintain sucient space
around the unit.
The space must be sucient enough to al-
low for safe lifting of the equipment, with no
risk for personal injury and/or damage to the
MPE 70. For more information about lifting
please see the installation guide “MPE 70
Installation instructions” in appendix 11.2.
7.2 Assembly MPE 70 to electric motor
The MPE 70 is mounted to the electric mo-
tor via a bell housing. Its is important to
follow the installation instruction given in
the Installation guide “MPE 70 Installation
instructions” in appendix 11.2. If alternative
mounting is desired, please contact Danfoss
High Pressure Pumps.

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7.7 Motor and frequency converter
7.7.1 Electric motor
The MPE 70 must only be driven by an
electric motor.
The rotation speed on the electric motor
must be controlled by a VFD. The direction
of rotation can be seen on the identication
label.
ERD
Type MPE 70
Code no. 180F7070
Serial no. XXXXXX01-XXX
MADE IN DENMARK
Danfoss A/S, 6430 Nordborg, Denmark
When connecting to the power supply,
check the direction of rotation. The rota-
tion can only be checked with water con-
nected and the transit screw removed.
This can be made by either:
1. Looking at the fan in the end of the
electric motor.
2. Removing the plug in the bell housing
and watch the rotation of coupling.
3. Before assembling the MPE 70 on the
electric motor, check the rotation of the
shaft.
Using anything other than an electric
motor can lead to an irreparable frac-
ture of the MPE 70’s internal parts.
Special attention has to be on NON
PROTECTED - FREE ROTATING shaft on
the electric motor. Ignorance will or
could result in personal injury.
Running the MPE 70 in the wrong
direction for more than a few minutes
can cause un-intended wear on the
MPE 70.
If the electric motor is running at
a lower speed, extra care must be tak-
en to ensure that the electric motor
is NOT overheated. External cooling
may be necessary.
7.7.2 Starting torque for the MPE 70
Because of the inertia and stick-slip friction
of the MPE 70 internal parts, the motor must
be able to provide the specied torque.
Once the MPE 70 is turning the torque will
drop to the operating torque specied for
the MPE 70.
7.7.3 Frequency converter
The frequency converter Must be able to
operate at constant torque over the whole
range of speeds. A special attention should
be taken when dimensioning the Frequency
drive for the MPE 70. The drive must be able
to provide start current enough for the mo-
tor to start. The start current can be found in
the data sheet see apendix 11.1.
If more electric motors are powered by the
same VFD, each electric motor must be
equipped with “torque limit equipment” to
protect the MPE 70 against overload.
The electric motor must always be
protected against overload.

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8.1 Safety regulations
The operator ensures that all in-
spection and installation work is
performed by authorised, qualied
specialized personnel who are
thoroughly familiar with the manual.
• Before starting up the MPE 70 and
the high-pressure pump, make
sure that the following require-
ments are met:
• The MPE 70 has been properly
connected to the electric power
supply and is quipped with all
protection devices in accordance
with EN 60204-1
• Check that all motor protections
are properly set.
• All safety equipment, auxiliary
equipment and connection re-
quired are properly connected
and operational.
• Check all bolts in all connections
and in the foundation of the MPE
70.
8.2 Support
Danfoss A/S oers commissioning and
service at system manufacturer’s location.
Rated quotes are oered upon request.
8.3 Commissioning
Before starting up the MPE 70 and the high-
pressure pump, make sure the following
requirements are met:
Slowly raise the pressure in the
system and set all pressure switches
to the correct limit and continually
check all connections.
• If pressure relief valve is present,
set pressure relief valve on both
low and high-pressure at the
maximum system pressure.
• Check high-pressure piping for
proper assembly and inspect for
external leakage for all connec-
tions. If there is no pressure relief
valve installed make sure the
brine concentrate valve is open
to allow pressure relief during
commissioning.
8. Commissioning,
start-up and shutdown
• All pipes are ushed, free from
debris and full of water.
• The MPE 70 has been bled and is
full of water.
• At pressure lower that 10 barg,
check the system for leakage.
The MPE 70 has a transit screw installed that
must be removed before startup. Instruc-
tions on this can be found in the installation
guide - Appendix 11.2.

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9.1 Safety regulations
The operator ensures that all main-
tenance, inspection and installation
work is performed by authorised,
qualied specialist personnel who are
thoroughly familiar with the manual.
Before intervening in the MPE 70/
system:
• The power must be shut o and
the main switch must be locked.
• The pressure in the high-pressure
lines must be drained to the low-
pressure side.
• The water in all connected pipes
must be drained.
Always use suitable safety and lifting
equipment when handling the MPE
70, and follow the instructions in
chapter 4.3.
• Assure correct settings of safety
equipment before start-up.
• When the system is re-started
after service and maintenance fol-
low the instruction in chapter 8.
9.2 Support
Danfoss A/S oers commissioning and ser-
vice at the system manufacturer’s location.
Rates/quotes are oered upon request.
9.3 Maintenance schedule
The schedule of preventive maintenance
below will help ensure that the MPE 70 pro-
vides years of trouble-free performance.
One day after commissioning:
1. Re-check bolts in the foundation
and the base plate of the MPE 70
and tighten the bolts to specied
torque if necessary.
2. Visually inspect all pipe con-
nections/couplings for external
leakage.
3. Re-check bolts in all pipe con-
nections/couplings and tighten
the bolts to specied torque if
necessary.
4. Note the operating current of
each individual MPE 70.
Three months after commissioning:
1. Re-check bolts in the foundation
and the base plate of the MPE 70
and tighten the bolts to specied
torque if necessary.
2. Re-check alignment of the MPE
70 base plate and MPE 70.
3. Visually inspect all pipe con-
nections/couplings for external
leakage.
4. Re-check bolts in all pipe con-
nections/couplings and tighten
the bolts to specied torque if
necessary.
5. Note and compare the operating
current at the VFD. If there is any
irregular results inspect varying
more than 25% we recommend
to inspect the internal parts.
Annually:
1. Re-check bolts in the foundation
and the baseplate of the MPE 70
and tighten the bolts to specied
torque if necessary.
2. Re-check alignment of MPE 70
base plate and MPE 70.
3. Visually inspect all pipe con-
nections/couplings for external
leakage.
4. Re-check bolts in all pipe con-
nections/couplings and tighten
the bolts to specied torque if
necessary.
5. Note and compare the operating
current at the VFD. If there is any
irregular results inspect varying
more than 25% we recommend
to inspect the internal parts.
9. Service/Maintenance