EN 14652 2005+A1 2007 64 e stf BRITISH STANDARD BS EN 14652 2005 +A1 2007 Water conditioning equipment inside buildings — Membrane separation devices — Requirements for performance, safety and testing[.]
General
Unless otherwise indicated, the following requirements shall be complied with and tested, if necessary on the complete system (device) as supplied by the manufacturer.
Materials
All membranes, components of the separation device, and additives that come into contact with drinking water must adhere to the applicable European Standards for materials and chemicals used in drinking water applications.
A device made entirely of components that meet the relevant European Standards does not need additional testing for materials in contact with drinking water, unless specified otherwise by national regulations.
The complete device will be tested in its final configuration according to the applicable test method, unless specified otherwise by national regulations, even if one or more components have not been specifically tested.
Products designed for water supply systems must adhere to national regulations and testing protocols to ensure their suitability for contact with drinking water Relevant regulators in member states oversee compliance with these standards.
EC Commission agreed on the principles of a future unique European Acceptance Scheme (EAS), which would provide a common testing and approval arrangement at European level
Upon the adoption of the EAS, European Product Standards will be updated to include an Annex Z/EAS under Mandate M/136, which will outline the testing, certification, and product marking requirements associated with the EAS.
Resistance to temperature
Within the service temperature range indicated by the manufacturer, the device shall not have any operating problems due to temperature exposure
Independently from above temperature range, the device should withstand a water temperature between 5 °C and 30 °C and between 5 °C and 35 °C for ambient air.
Resistance to hydrostatic pressure
The device must withstand a hydrostatic pressure of three times the nominal design pressure, ensuring no damage or leakage occurs This pressure should be at least 1 MPa, or 1.6 MPa if it is connected to a pressure regulating valve, as specified in section A.2.1 during testing.
Resistance to cyclic pressure
The device shall withstand a cyclic pressure fluctuating between 150 kPa and 1,3 times the design nominal pressure, with a minimum of a 1 MPa, when tested as defined in A.2.2.
Backflow prevention
The device shall include an upstream backflow preventer in accordance with EN 1717.
Electrical safety
The device shall comply with the relevant safety regulations.
Noise level
The device shall comply with EN ISO 3822.
Air vent
The device shall ensure that any trapped air is removed in any operating condition.
End connections
The fittings for assembling the device and connecting it to the water main must meet the specifications outlined in the relevant European and International Standards, including EN 1092-1, EN 1092-2, EN 1254-1, ISO 7-1, and EN ISO 228-1.
Drain connections
Any drain fitting of the device shall be disconnected (air gap) from the drainage system in accordance with
Component replacement
Any special tool necessary for routine maintenance shall not come into contact with the water intended for human consumption and shall be provided by the device supplier
The device shall be designed, and suitable instructions shall be provided, such that contamination of the treated water supply is avoided during the component replacement procedure.
Back-washable modules (MF and UF)
Back-washable modules shall be capable of being cleaned automatically without the aid of tools and the mechanism shall not compromise to the quality of the drinking water
After back-washing, the module performance shall be recovered
The back-washable module shall be fitted with a free drain outlet in accordance with EN 1717
General
The membrane module performance shall be specified by the manufacturer
This clause details the minimum acceptable performance level dependent on the type of device, together with appropriate test methods
The performance evaluation will focus solely on the membrane module, excluding any pre-treatment or post-treatment processes Additionally, the challenge water must only include the specific contaminants that the device is designed to eliminate, without any other contaminants typically addressed by pre-treatment or post-treatment methods.
Hydraulic performance (applicable to MF, UF)
The manufacturer shall declare the maximum pressure drop through the membrane module at the recommended flow rate
The claim shall be tested in accordance with the test method defined in A.1.1
The maximum pressure drop shall not exceed the declared value by more than 10 % at the recommended nominal flow rate.
Mechanical performance
7.3.1 Housing resistance to static pressure
When subjected to a static pressure test as defined A.2.1, the module housing shall show no permanent, visible signs of leakage, permanent deformation, cracks or breaks
7.3.2 Cyclic pressure test of housing
When tested in accordance with A.2.2, the filter housing shall satisfy the requirement of resistance cyclic pressure variations without showing permanent deformation or leakage
7.3.3 Module resistance to differential pressure (collapse pressure)
When subjected to continuous and progressive blinding up to a pressure drop of 80% of the nominal pressure rating, the module must show no discontinuity in pressure rise Additionally, after thorough removal and cleaning, there should be no visible damage to either the module or its housing.
7.3.4 Module cyclic differential pressure resistance (applicable to MF, UF membranes operating in dead-end mode)
When subjected to a cyclic flow of water sufficient to generate a peak pressure drop of 200 kPa, or greater, at a cycle frequency of 0,05 Hz, for 500 cycles in accordance with A.2.4:
pressure drop at the peak flow rate shall not fall off during the test;
there shall be no visible evidence of damage to the module;
bubble point for the module after the test shall not differ from that measured before the test, by more than
Functional performance
7.4.1 Grade of filtration (particles rating)
Each membrane is claimed by the manufacturer to reject specific substances (e.g particles of given size, organic molecules, different ions) to a specified extent (percentage or log-reduction)
The test procedure shall be appropriate to the manufacturer’s claims and the relevant test methods could need to be adapted for the specific performance being claimed
The following performance requirements are the ones commonly adopted for evaluating different types of membranes
Most manufacturers of microfiltration (MF) membranes do not utilize the testing method outlined in section A.3.1 to assess membrane efficiency based on claimed particle ratings Instead, they typically employ integrity testing methods to evaluate how effectively a membrane device rejects specific particles of interest.
Integrity tests primarily utilize the First Bubble Point principle, where the surface tension of water in a membrane's pores resists air passage when pressure is applied The Bubble Point represents the minimum pressure needed to counteract this surface tension, which is inversely related to pore size Consequently, the First Bubble Point measurement allows for the determination of the membrane's largest pore size.
In practice the application of the test method is limited to the detection of membrane defects (pores larger then
1 àm to 2 àm, i.e bubble points of 200 kPa to 100 kPa) while the integrity (log-reduction value) is directly measured with challenged water
Due to the existence of various proprietary bubble point test methods developed by membrane manufacturers, it is essential to collaborate with the manufacturer and the testing laboratory to determine the appropriate testing methods for microfiltration (MF) membranes.
In principle, the bubble point test methods are applicable to any membrane (MF, UF, NF, RO) for detecting defects
7.4.1.2 Filtration rating (applicable to MF)
The MF module, installed in the recommended pressure vessel by the manufacturer, must demonstrate a filtration efficiency of at least 99.8% at the specified particle rating and maximum pressure drop, as per the testing method outlined in A.3.1.
7.4.1.3 Organic molecule rejection – molecular cut-off (applicable to UF and to NF and RO only, if claimed)
When the membrane module is tested in accordance with A.3.2, the rejection rate shall not be less than 90 % of the manufacturer's stated value
NOTE If the membrane is claimed to reject specific organic molecule(s), the challenge water will be spiked with the relevant contaminant(s) In that case the membrane/device manufacturer declares:
- minimum and/or maximum contaminant concentration in the challenge water;
- minimum rejection rate in the given concentration range;
- other testing conditions, which may affect the rejection rate, to be complied with
In that case, such conditions will be clearly recorded in the performance data sheet of the device (see 8.3)
7.4.1.4 Salinity rejection rate (applicable to NF and RO)
When tested in accordance with the test method described in A.3.3, the membrane module shall achieve a rejection rate of at least 99 % of the manufacturer's stated value
7.4.2 Recovery rate (daily production rate) (applicable to MF, UF, NF, RO operating in cross-flow mode)
The recovery rate shall be calculated when testing the relevant rejection rate (7.4.1.1, 7.4.1.2 and 7.4.1.3) in accordance with the test method described in A.3.4
The actual calculated recovery rate shall be at least 95 % of the claimed recovery rate
The recovery rate should only be calculated if the corresponding rejection rate test has been successfully passed; otherwise, the compliance of the recovery rate is irrelevant if the rejection rate does not meet the specified criteria.
When tested in accordance with A.3.4, the daily production shall be at least 95 % of the value claimed by the manufacturer
Installation, operation and maintenance instructions – Instruction manual
The influent water characteristics, including chlorine, bacteria, pH, temperature, iron, turbidity, hardness, and pressure, must meet specific requirements as outlined by applicable national regulations, ensuring that they do not adversely affect the membrane or other components.
Information setting forth complete, detailed instructions for installation, operation, and maintenance shall be provided with each system Specific instructions shall include:
complete name, address and telephone number of manufacturer;
type of device, model number and trade designation;
production rate in l/d and peak flow rate in l/s for the specified and applicable operating conditions, e.g pressure drop in kPa;
maximum and minimum working pressure in kPa;
maximum and minimum operating temperature in °C;
detailed installation instructions including a description or schematic diagram of proper connection to the installation system as required by national regulations;
operation and maintenance requirements, including user responsibility recommended spare parts, removal and disposal of consumables, etc., and where that maintenance and servicing are provided by a third party;
diagram showing proper air gap installation to drainage system as stated in EN 1717:2000, Clause 9;
statement describing the amount of water discharged as reject water, if applicable.
Marking and data plate
The direction of the water flow through the device shall be indicated by a clear and durable marking and shall be visible after installation
A permanent plate or label shall be affixed to the system in a readily accessible location and shall contain at least the following information:
name and address of manufacturer;
The after-sales service provider's name and address must be clearly stated Additionally, if applicable, a supplementary label should be provided by the third party responsible for maintenance and servicing, including their name and address.
maximum and minimum working pressure in kPa.
Performance data sheet
A performance data sheet shall be made available to potential buyers for each system and shall include the following information:
complete name, address and telephone number of manufacturer;
model number and trade designation;
reduction capabilities for specific contaminants verified to be reduced by test data including, in tabular form:
average influent and product water level during test and resulting percent reduction;
test parameters (temperature, pH and pressure);
maximum and minimum working pressure in kPa;
maximum and minimum operating temperature in °C;
general installation conditions and needs;
general operation and maintenance requirements including, but not limited to:
suggested frequency of element and cartridge(s) replacement or service;
Where applicable and appropriate, the following information shall be included:
model number of replaceable treatment components
Testing the differential pressure is applicable to MF and UF membranes operating in dead-end mode
NOTE The following test should be performed after having tested the compliance of the module (with or without its housing) with the relevant performance test
The test consists of imposing an increasing flow rate of water through the device with the membrane module and measuring the corresponding differential pressure
The test rig consists of several essential components: a pressurized water source that provides a flow rate 20% above the maximum test flow, equipped with a control device for continuous flow variation; a tank designed to prevent air entrapment and particle ingress; a temperature gauge and regulator maintaining (25 ± 2) °C; a clean-up filter with a threshold smaller than 0.2 µm; pressure tappings on a straight pipe positioned approximately 6 times the inside diameter upstream and 4 times downstream of the filter; the test liquid, which is permeate from a reverse osmosis unit, must be freshly prepared within 24 hours prior to testing; and measuring instruments that meet specified precision requirements.
flow rate: ± 2 % of actual value;
1 Tank with test liquid (RO permeate)
Figure A.1 — Typical layout of a rig for determination of the differential pressure of a filter element versus flow rate
To validate the test rig, first install the housing without the membrane module Next, circulate the test liquid at 1.2 times the nominal liquid flow rate (Qv) until the temperature stabilizes within the range of 25 ± 2 °C and, if needed, until the circuit is clean Finally, confirm that there is no air present and that the pressure values remain stable.
To test the module housing, first verify that the water flow remains largely unchanged without the membrane module If flow perturbations occur, use a substitute element, such as a perforated tube, to replicate the flow path of the module, ensuring the substitute's passage section is maximized to reduce pressure drop Document the characteristics of this substitute in the test report Next, adjust the flow rate to 0.2 Qv and record the initial pressure (P1), differential pressure (∆P), and the temperature of the test liquid Repeat this process for increasing flow rates in increments of 0.2 Qv, up to 1.2 Qv, and calculate or record the differential pressure across the filter housing for each increment.
To test the device, first install the module in the housing and mount the assembly on the test rig, ensuring the bypass is fully closed Next, establish circulation to expel air from both the housing and the circuit Finally, repeat the operations outlined in section A.1.4.2 b) to d), carefully maintaining the same flow rate increments throughout the process.
A.1.4.4 Characteristics of the module only
Calculate the pressure drop generated by the filter element only, by deducting the values obtained with the housing only, from those measured on the housing together with its module
Report all test conditions and results Plot curves ∆P = f(Q v) for the housing alone, for the complete assembly and for the module alone
A typical test report is given in C.1 and a typical test curve is shown in Figure C.1
A.2.1 Housing resistance to static pressure (applicable to MF, UF, NF, RO membranes)
The pressure strength and water tightness of the module housing shall be tested by applying a water pressure of 3 times the nominal pressure PN for a period of 10 + 2 0 min
Components exposed to hydrostatic pressure must be designed for a minimum nominal pressure of 1,000 kPa According to EN 1567, devices that include pressure regulating valves should be designed for a nominal pressure of at least 1,600 kPa.
A.2.1.2 Procedure a) Install the housing in a test rig as shown in Figure A.2
The cyclic water pressure test of housing involves several key steps: first, flush the system with water to eliminate air from the circuit Next, increase the pressure to three times the nominal pressure (PN) and sustain this pressure for a duration of 10 ± 2 minutes Finally, inspect the housing for any visible signs of leakage or damage.
A.2.2 Cyclic water pressure test of housing (applicable to MF and UF membranes operating in dead-end mode)
The housing shall be capable of withstanding not less than 100 000 load cycles with a pressure cycling between 150 kPa and 1,3 times the nominal pressure PN, at a frequency of (15 ± 2) min -1
To conduct the procedure, position the separation device in the test rig as illustrated in Figure A.2 Open both solenoid valves fully and adjust the inlet solenoid opening stop to achieve an inlet pressure of 1.3 times the nominal pressure (PN) Next, close the inlet valve and set the closing stop to establish an inlet pressure of 150 kPa Apply 100,000 load cycles, varying the water pressure between 150 kPa and 1.3 times the nominal pressure at a frequency of (15 ± 2) min⁻¹, ensuring that the duration for pressure increase, hold, and decrease is (1 ± 0.2) seconds each Finally, inspect the housing for any visible signs of leakage or damage, noting that the housing used for this test should not be reused for future testing.
A.2.3 Module resistance to differential pressure (collapse pressure) (applicable to MF and UF membranes operating in dead-end mode)
This test aims to evaluate the membrane module's ability to endure the specified differential pressure of liquid in the normal flow direction without experiencing collapse or rupture.
The test involves circulating a contaminated liquid through the module within its housing at a designated flow rate until clogging occurs and a specific pressure loss is achieved Following this, it is essential to confirm that the module remains visibly undamaged.
A.2.3.2.1 Test rig (see Figure A.4) comprising device test circuit and injection circuit
1 Main tank with test liquid (RO permeate) 7 Tap to the control level
8 Clean-up filter A Outlet to sewage
2 Main pump 9 Injection tank C Device test circuit
3 Temperature regulator 10 Recirculation pump D Injection circuit
Figure A.4 — Test rig for the collapse pressure test A.2.3.2.2 Device test circuit
The device test circuit consists of several key components: a conical bottom tank with a cone angle of 90° or less and a volume of approximately 6 liters, designed for liquid entry below the surface to avoid air entrapment; a circulation pump that can achieve the required maximum differential pressure and flow rate while being resistant to concentrated contaminants; instruments for measuring temperature, differential pressure, and flow rate, all compatible with specified connections; appropriately sized piping and connectors to ensure turbulent flow and minimize particle segregation; a temperature regulator to maintain a stable temperature of (25 ± 2) °C; a drain line and valve for controlling the main tank's liquid level; and a clean-up filter with a 0.2 µm rating.
A.2.3.2.3 Circuit for the injection of the contaminant
The injection circuit consists of several key components: a conical bottom tank with a maximum cone angle of 90° and a capacity of approximately 6 liters, equipped with a contents gauge, where the return liquid enters below the surface; a recirculation pump that provides adequate flow for optimal mixing during testing, resistant to the contaminant without degrading its particles; and an injection pump that transfers the contaminated fluid from the recycle pipe at a turbulent flow point, discharging it through a flexible pipe into the main tank of the test circuit.
This can be a housing supplied by the manufacturer or a suitably adapted vessel
Silica dust as defined in ISO 12103-1 (ISO FTD, particle size 0 àm to 80 àm)
The measuring instruments shall have the following accuracy:
flow rate: ± 5 % of actual value;
In addition, they shall be resistant to the anticipated conditions of the test
For the application of this test, the following shall be specified by the manufacturer:
flow rate through the module;
nominal pressure of the housing and of the module alone;
To conduct the test, rinse both circuits three times by circulating the test liquid for 10 minutes at the maximum flow rate, ensuring the clean-up filter is isolated Verify the integrity of the test module and set up the test housing on the rig without the module Circulate the test liquid at a temperature of (25 ± 2) °C and the manufacturer's specified flow rate, noting the test flow rate, differential pressure (∆P h), and liquid temperature Prepare the injection circuit by adding approximately 6 liters of tap water and a contaminant mass 20% greater than the expected mass M to generate the specified ∆P within about 1 hour Adjust the injection pump flow rate to about 5 l/h and install the module in the test housing Subject the module to the specified flow rate and temperature, recording the differential pressure across the clean unit (∆P m) Insert the injection pipe into the main tank and activate the pump while maintaining the test flow rate, and finally, record the differential pressure across the test housing.
If the differential pressure steadily increases, continue injecting the contaminant until the differential pressure is equal to that of the end test differential pressure and proceed as in k)
If the differential pressure remains constant or decreases for at least 3 minutes before reaching the specified end of test differential pressure, it indicates potential issues such as cracking in the cake or structural degradation of the module In such cases, it is essential to follow the outlined procedure Conversely, a steady increase in pressure loss should also be monitored closely.
At the conclusion of the test, once the differential pressure is achieved, cease the operation of the injection pump Activate the clean-up filter and circulate the fluid for 30 minutes, then document the module's ∆P f.
To ensure accurate testing, first stop the main pump and carefully remove the module from the test housing for cleaning, avoiding any damage Inspect the module for visible defects or distortions If a decrease in differential pressure occurs before reaching the test's end point, or if it remains constant, stop the injection pump followed by the main pump Record the differential pressure \(\Delta P_i\) at the inflection point on the curve \(\Delta P = f(t)\), subtracting the differential pressure of the test housing \(\Delta P_h\).