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Calculation of Pure Water Permeability(PWP)

Used to check the current state of cleanliness of themembrane

To make the calculation, use the Osmosis record and Correction factorsin Annexes 2 and 3. See example in Annexe 1.

1- When buying a new membrane, start the osmosis system,take the rate of ow (!min ou gal!min) and list it in ColumnC of the "smosis #ecord$

[For a used membrane, soap can be used at the beginning of theseason before calculation]

[If the owmeter doesnt work, note the time required for a certainquantity of water to pass through the membrane. ist the !olume"# and the time "minute# in $olumns % and &. 'o obtain the owrate, di!ide the !olume by the time "% ( & ) *min# and list in$olumn $.]

%- &easure the tem'erature of ltrate and list in Column $

*- With the table (see anne+e 1), nd the correction factorcorres'onding to the tem'erature of ltrate$

['he temperature of the +ltrate can !ary its speed, so a correctionfactor is used to obtain comparable results.]

- &ulti'ly the debit of ltrate by the correction factor andlist the result in Column (C + . / PWP !min)$

['he +rst - result is our // 0. 'his result is used to determinethe loss of e1ciency of the membrane during the season.]

0- o calculate the e2ciency of membrane during theseason, di3ide the PWP result calculated during theseason by our rst 1445 PWP result$ hen, multi'ly thisresult by 144 to obtain a 'ercentage$

2oap can be used when e1ciency is lower than 340.

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5ote6 7ther similar tables e8ist. For some, the +ltrate ow is di!ided"not multiplied# by the correction factor. In such cases, 2chedule 9 isnot representati!e. -e must use another table of correction factors.

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6''endi+e 1

.+am'le of Pure Water Permeability (PWP)Calculation

"2ee the record completed in anne8e :#

6t the beginning of season7

;ebit of

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Date

Activit!Cleanin",rinse#$

%um&er ofhours ofoperation

Cum.'rshrs

6Bolumeused to

+ll

"liters#

8'ime

requiredto +ll

Bolume %

"min#!sec$

CFiltrate

ow"*min#

% * &"l*min#

A() * +

'= at theoutlet of+ltrate

"=$ or F#

.$orrection

Factor

"2ee'able#

-

$ 8 @

9@1ciency

of themembran

e%ctual

- // 0-

-roductused

t ofrinse/aterused

-e

ch

&arch%*

Cleaning 0 4 l!min 14 C 1,4:: *,0% 1445 8iomembrane

;44gal i$b

+++ #ince 0 14 ++ +++ +++ +++ +++

6'ril < Cleaning 0 10 *4 l!min < C 1,1:: *0,; :1,:=5

(*0,;!*,0% >144)

8iomem

brane

;44gal i$b

6nne+e %

"smosis #ecord (.+am'le)

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6nne+e *

Correction actors for all ty'es of membrane>

? ofltrateCelsius

? ofltrate

ahrenheit

Correctionactor

4 *% 1,::1 * 1,*=% *; 1,*=1* *< 1,*: *= 1,*400 1 1,%;;

; * 1,%%;< 0 1,1::: ; 1,100= : 1,1%414 04 1,4::11 0% 1,40