Technical question: What is the filtration efficiency of the recirculating water side filter (Akro disc filter)?
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This post was last edited by hesonchang214 on 2010-1-31 08:37. Our company’s circulating water system handles a flow rate of 60,000 tons per hour; 6 Akzo disc filters are in use, with a total side filtration capacity of 3,000 tons per hour. The operation of these filters is very poor due to severe clogging. Has anyone used disc filters as bypass filters in a circulating water system, and what were the results? Hope to share!
1. The effect should be decent; we used ARKAL in both batches, usually at a side filtration rate of 5%； 2. The filter is clogged. What’s the quality of your water like? Have you just started driving it, or has it been running for some time already?
It depends on your water quality standards. It is commonly used in China, and we take this device into consideration when designing. 1. Tap water, which has good quality; it’s an excellent choice to use this. Many projects have provided evidence of this. II. The water quality is relatively poor; especially when it contains soluble colloids or has a high level of TOC, as well as a high COD value, this device does not perform very well. We can see from Arko’s research and development that initially they used it for filtering Israeli sand, mainly to remove large impurity particles such as sand, but it was very ineffective against soluble organic substances.
What was said upstairs makes a lot of sense – there is no best filtering equipment, only the most suitable one
Clogging is a common problem; on the one hand, it indicates that the SS level in the circulating water is high and requires treatment, and on the other hand, it shows that this system still needs further improvement through practical use. Using a side filter certainly gives good results. However, the requirements for water quality are also high; in some systems, it won’t be a problem if the bypass filter is removed.
When the same device is used in different regions, differences in water quality will inevitably lead to varying performance – some devices work well while others do not. So, in my opinion, it is still the water quality that determines the equipment – the type of water quality requires the use of a suitable product. Things that work well for others may not be suitable for you, and things that don’t work well for others may not fail to work well for you either! The Akko lamella filter is suitable only when there is very little suspended solids in the water and they are mainly in the form of suspended particles. It tends to get clogged in situations where the water quality is poor, with high levels of suspended solids and the presence of colloidal substances, making it less appropriate for such conditions.
Disc filters are self-cleaning filters; if your water contains impurities such as fibers (like hair) or colloidal substances, then good news – the filter will get clogged frequently
Lamellar filters can remove particulate suspended solids. However, in closed-loop water systems, the high concentration leads to a high level of organic matter, which can easily cause the filters to become clogged; therefore, lamellar filters are not suitable for such systems.
Circulating water systems generally have a bypass filtration system, and bypass filters have their own operating conditions. The effectiveness of selecting within its range should be guaranteed.
I recommend using a gravity-fed sand filter; a design capacity of 3% of the circulating water volume in the circulation system is sufficient, and no pumps are needed as a power source
Aren’t there also self-priming filters produced by ELI? It’s not prone to clogging; if the water quality is poor, it just needs to be backwashed frequently.