MICRODYN CAPILLARY MODULES | USER MANUAL
MANN+HUMMEL Water & Fluid Solutions | REVISION DATE: 09/09/2021
19
5.6
CHEMICAL CLEANING
Regular chemical cleanings are recommended to help maintain the module over time. Chemical cleanings require acidic or caustic
solutions with a pH within the range of 0.5 to 14. The cleaning chemical solutions may be flushed through the membrane from the
permeate side. Employing a cross-flow along the membrane surface at low pressure also has a favorable effect on the cleaning
process; it is very effective and saves cleaning agents. In fact, unspent chemicals may be pumped down for further use.
The following steps describe how to properly clean the modules:
1.
Uncouple the filtration system from other systems
2.
Empty the system on both sides of the membrane (feed and filtrate)
3.
Flush the system with clean water and drain again
4.
Fill the system completely with the cleaning solution (e.g. sodium hydroxide) from the filtrate side
5.
The cleaning chemicals must soak in the module for 30 minutes to 1 hour
6.
Drain the complete system
7.
Flush the system with clean water to remove residual cleaning agents
8.
Repeat steps 4-7 with another cleaning solution (e.g. citric acid) if required
9.
Connect the filtration system to the other systems.
Circulation Pump
Feed
SEPRODYN
®
Module
To Drain
(Concentrate Side)
To Drain
(Permeate Side)
Aeration &
Deaeration
Aeration &
Deaeration
Cleaning
Agent
DI Water
Notes to be considered during cleaning:
•
Cleaning temperatures must not exceed those listed on the product data sheets.
•
Detailed cleaning instructions must be determined on-site and are depending on the application.
•
Organic fouling of the membrane is predominantly cleaned by using alkaline cleaning agents. Typically, 1-5% NaOH is
used at a temperature of 20-60°C (68-140°F).
•
Cleaning aids (e.g. surfactants) speed up the dissolution of oily and greasy substances.
•
Inorganic fouling (e.g. mineral salts, ferrous compounds) is removed using acidic agents. Organic acids like citric acid,
oxalic acid, or mixtures of hydrochloric acid and oxalic acid have proven favorable.
•
For more information about cleaning, please consult MANN+HUMMEL WFS.
Figure 16
.
CIP flow diagram
