In factory-scale recirculating aquaculture systems, water quality management is the core factor determining the success or failure of aquaculture. The microfiltration machine, as the first line of defense in water treatment, directly affects the health of farmed organisms and the operational efficiency of the system.
However, many farmers have insufficient understanding of its function, principle and common problems, which leads to improper equipment selection and inadequate maintenance, ultimately affecting the breeding benefits! Today, let's take a deep dive into the microfiltration machine and uncover its true colors!
I. The Function of Microfiltration Machines
1. Remove suspended solids
Microfiltration machines can effectively remove suspended solids from water, including feed residues, fish feces, dead aquatic organisms, and sediment, reducing the organic load in water bodies. Its filtration accuracy ranges from 100 microns to 30 microns.
2. Reduce the load on the biological filter
The microfilter intercepts and removes small particles that the vertical flow sedimentation tank cannot remove through mechanical filtration, reducing the organic load of the biological filter, providing a more suitable growth environment for nitrifying bacteria, and improving the treatment efficiency of the entire system.
3. Enhance the effectiveness of ultraviolet disinfection
In recirculating aquaculture systems, microfiltration machines and ultraviolet disinfection equipment usually work in coordination. As a pre-treatment device, the microfiltration machine first removes solid suspended matter and larger impurities from the water, enabling the subsequent ultraviolet disinfection to function more effectively. After being filtered by a microfiltration machine, the transparency of the water increases and the suspended solids in it decrease. As a result, ultraviolet rays can better penetrate the water body and reach the microorganisms in it, thereby enhancing the disinfection efficiency.
Ii. Working Principle of Microfiltration Machine
The principle of a microfiltration machine is actually very simple. The core steps are just two:
1. Physical interception: The aquaculture water passes through the drum filter screen, and the suspended solids are firmly trapped on the inner side of the filter screen. Clear water passes through the filter screen and flows back to the aquaculture ponds, achieving "solid-liquid separation".
2. Automatic backwashing: When the filter screen is clogged, the system automatically starts high-pressure backwashing. The reverse water flow washes the adhering substances into the sewage pipe, restoring the filter screen to its permeability. The entire process requires no manual intervention!
Iii. Minefields for the Use of Microfiltration Machines
Minefield 1: Is higher filter screen precision always better?
Error: Excessively high precision (such as less than 20 microns) is prone to clogging, which instead increases energy consumption and cleaning frequency.
The correct approach: Select based on the farmed species (for example, choose 60-80 microns for prawns and 40-60 microns for sea bass).
Minefield 2: Neglecting the maintenance of the backwashing system
Consequences: Filter screen clogging → Water flow slowing down → Water quality deterioration → Death of fish and shrimp!
Solution: Check whether the backwash nozzles are clogged every month and clean the sewage pipes regularly.
Minefield 3: Disconnected from Biological Filters
Misconception: Believing that microfiltration can solve all water quality problems.
The truth is that it is responsible for removing suspended solids, but ammonia nitrogen and nitrite need to be decomposed by the biological filter, and the two need to be used in combination!