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MICRODYN BIO-CEL XS-1 Pilot Plant Manual // Revision: A // Date: Jul. 25, 2018
Cleaning
Depending on the type of fouling and required cleaning, a sodium hypochlorite solution, citric acid
solution or combinations of the two may be required. Sodium hypochlorite is used to remove
organic and biological fouling from the membrane while citric acid is used to remove mineral
scaling such as iron, metal salts or calcium salt and other scaling compounds.
Important Information
SODIUM HYPOCHLORITE
AVOID EXPOSURE TO HEAT AND DIRECT SUNLIGHT!
-
STORE IN COOL (T <15°C or 59°F) AND DARK CONDITIONS
-
PLEASE NOTE THAT THE ACTIVE CHLORINE CONCENTRATION WILL DEGRADE
OVER TIME AND RENDER CLEANING SOLUTIONS LESS EFFECTIVE OVER
TIME.
To safely perform chemical cleanings and safely store chemicals, please follow the in-
structions provided by the chemical manufacturer. The pH range and maximum concen-
tration for chemicals used for cleaning purposes should not exceed the limits of the MI-
CRODYN BIO-CEL
®
MBR module as listed on the module data sheet. For further infor-
mation, please contact the chemical manufacturer.
In full-scale applications, regular cleaning (maintenance cleaning) is done by dosing chemicals
directly into the backwash flow of the permeate pipe. The MICRODYN BIO-CEL
®
XS-1 pilot plant
has no automatic cleaning integrated, cleaning needs to be done manually.
The frequency of cleaning depends on several factors such as:
•
Temperature corrected permeability
•
Type and chemistry of wastewater
•
Scaling and fouling potential
•
Membrane conditions (extent of fouling)
•
Efficiency of production cycles (backwash and relaxation)
•
Operating temperature
•
Pretreatment efficiency
•
Completeness of biological degradation
•
Permeate flow rates
•
Aeration intensity
For all municipal and most industrial applications with systems using MICRODYN BIO-CEL
®
MBR modules, the maintenance cleaning frequencies are 1-2/week with Sodium Hypochlorite
and 1/2week with citric acid.
Please check and note the normalized permeability before and after the chemical cleaning. A
template for a chemical cleaning log book is provided in Chapter
Fehler! Verweisquelle konnte
nicht gefunden werden.
of the MICRODYN BIO-CEL MBR Operation and Maintenance Manual
and is used to collect essential data for continuous improvement of the cleaning strategy.
This maintenance cleaning can be done for a biomass/process. The maintenance cleaning pro-
cedure is summarized below:
Table 5
:
Maintenance Cleaning procedure
*
Steps
Procedure
1
•
Stop feed pump, stop filtration. Continue to aerate membranes for 5 minutes.
2
Backwash clean water manually.
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