Tertiary Wastewater Filtration Equipment |CQ9-II Semi-Submerged Disc Filter

Working Principle

After wastewater enters the tank, only the lower half of the discs is submerged. Clear water passes through the filter cloth into the central pipe, trapping suspended solids. When the pressure differential reaches the set point, automatic backwashing begins. The discs rotate, and high-pressure water sprays from the inside out to wash the upper half exposed to the air. This design greatly reduces head loss, making it ideal for tertiary wastewater filtration projects that demand high water quality and energy efficiency.

Application Fields

1.Municipal wastewater upgrades: deep filtration of secondary clarifier effluent, replacing traditional sand filters.
2.Industrial wastewater treatment: final polishing of printing and papermaking wastewater to reduce effluent SS.
3.Water reuse: pre-filtration to protect membrane systems.
4.Surface water purification: removing fine suspended solids from river and reservoir water.

FAQ

Q1: What is the difference between the CQ9-II and a traditional fully submerged unit?
A: Traditional fully submerged units have higher resistance. The semi-submerged design allows water to flow through only the lower half of the discs, significantly reducing head loss. Additionally, you don't need to drain the tank for backwashing—you can spray the exposed surface directly, making maintenance easier.

Q2: What filtration rating can it achieve?
A: Depending on the filter cloth pore size, it typically achieves 10–20 microns. With special cloth, effluent turbidity can be kept below 1 NTU, meeting strict reuse standards.

Q3: Does this tertiary wastewater filtration equipment use a lot of water for backwashing?
A: Not much. The unit draws clean water from the downstream side for high-pressure backwashing. Backwash water usually accounts for only 1%–3% of the production volume, saving significant water.