Why does the filter need frequent backwashing?
Author:
Release time:
2020-05-25
Disc filters are frequently used in water filtration systems. They are popular with users due to their ability to achieve high filtration accuracy. However, during operation, occasionally issues arise where excessive pressure difference at the inlet and outlet of the disc filter leads to continuous backwashing, preventing normal water output and affecting production efficiency. This article will analyze the reasons behind frequent backwashing in disc filters.
A disc filter is a highly efficient filter medium formed by stacking plastic discs with special grooves, creating a large filtration area. Suspended matter is intercepted on the outer surface of the discs.
There are two cleaning methods for the filter:
● Manual cleaning by removing the discs
● Backwashing without removing the discs. The filter is equipped with a drain valve and two pressure gauges (used to detect the pressure difference at the filter inlet and outlet)
System operating pressure: 2.5～10 bar; Backwashing pressure: 1.5～10 bar
Operating temperature: <60℃
pH value: 4-13
Number of filter units: 3'(3-16 units) and 4'(4-16 units)
System backwashing method: Each unit is backwashed sequentially using the effluent from other filter units until all units are complete.
Inlet pipe: Corrosion-resistant carbon steel/stainless steel, flange connection;
Outlet pipe: Corrosion-resistant carbon steel/stainless steel, flange connection;
Drain pipe: Flange connection
Backwashing valve: Cast steel/plastic material
System controller: Fully automatic dedicated controller, insulation grade is IP65 international standard
I. Classification of raw water quality:
A. Excellent water quality: Municipal tap water, well water drawn from stable aquifers;
B. General water quality: Recirculating cooling water, settled surface water, wastewater that has undergone effective sedimentation and complete biological treatment;
C. Poor water quality: Groundwater drawn from aquifers with poor water quality, wastewater that has undergone effective sedimentation but little or no biological treatment, surface water with extensive microbial growth;
D. Very poor water quality: Well water drawn from very dirty or iron- and manganese-rich wells, surface water affected by floods and without sedimentation, wastewater without sedimentation and biological treatment.
Different raw water qualities significantly affect the filter's operating cycle. Typically, system selection should ensure a backwashing interval of no less than 1 hour.
II. The Importance of Filter Accuracy Selection:
Selecting the filter accuracy, i.e., the disc, is crucial for ensuring the disc filter system's effectiveness in the overall water system. Only by making the right choice can subsequent water quality requirements be met. The table below shows the recommended filter accuracy for common centralized filtration applications. If the user selects the wrong accuracy, it can easily lead to the disc filter head becoming clogged. Even with an automatic backwashing disc filter, this can result in incomplete cleaning, necessitating the disassembly of the unit head for manual inspection and removal of blockages. To avoid this problem, a good understanding of the raw water quality is essential. Don't solely focus on high accuracy while ignoring your water quality, as this can lead to such issues.
RELATED INFORMATION
2024/09/18
2024/06/08
2023/10/13
Follow us
Fuzhou Yong Run Irrigation Equipment Co.,Ltd
Address: Hongkuan Industrial Village, Fuqing City
Mobile:+86-15959188079 (Ms. CHAN Mei-fung)
Landline:+86-591-22212272
Fax: +86-591-86392276