Efficient nitrogen and phosphorus removal process system for mariculture tail water treatment

A nitrogen and phosphorus removal process system for mariculture tail water treatment, comprising a physical filtering device, a biological treatment unit, a flocculation sedimentation tank, a sand filtering tank, a clean water tank and a sludge tank, wherein the physical filtering device, the biological treatment unit, the flocculation sedimentation tank, the sand filtering tank and the clean water tank are sequentially connected;

• the physical filtering device, the biological treatment unit, the flocculation sedimentation tank and the sand filtering tank are all connected with the sludge tank through pipelines;
• and the physical filtering device and the sand filtering tank are both connected with the clean water tank through pipelines;
• wherein the biological treatment unit comprises a biological aerated filter 1, an anaerobic tank, a biological aerated filter 2, a modified hydrophilic wear-resistant filter and a glass fiber reinforced plastic grid cover plate, the biological aerated filter 1, the anaerobic tank and the biological aerated filter 2 are sequentially connected, the modified hydrophilic wear-resistant filter is filled in the biological aerated filter 1, the anaerobic tank and the biological aerated filter 2, the glass fiber reinforced plastic grid cover plate is located at the upper parts of the biological aerated filter 1, the anaerobic tank and the biological aerated filter 2, and the modified hydrophilic wear-resistant filter is pressed to prevent floating;
• wherein the physical filtering device is selected from the group consisting of a microfiltration machine and a curved screen with an automatic backwashing function;
• and in the nitrogen and phosphorus removal process system, except that a water body is lifted by a pump once before the physical filtering device, all subsequent water bodies are realized by gravity.