1. Conventional Sedimentation Introduction:

It achieve suspends removal by adding PAM/PAC in the settling tank and sediment through natural gravity.

 Conventional clarifier /DAF etc is technology need huge concrete tank and takes very big land area and consumpts too much chemicals.The retention time is too long. The sludge has higher moisture,so it need big capacity dewatering equipment.

2.Magnetic flocculation Introduction：

 The magnetic flocculation equipment is suitable for the treatment of most of the sewage and wastewater with high content of suspended solids and colloidal substances. It uses the high-strength magnetic energy product of rare-earth permanent magnetic materials to achieve high magnetic field strength and high magnetic field gradient through the combination of rare earth disks.

Under the action of the magnetic field force, the magnetic flocs formed can overcome fluid resistance and gravity etc mechanical external forces, and generate rapid directional movement, and adhered on the surface of the rare earth disk, thereby adsorbing and separating the pollutants in the wastewater, and then magnetic isolation and slag unloading device unload the adsorbate and dig it into the spiral groove,outputs it through the slag conveying device to realize continuous purification and recycling of wastewater.

Brief description of process flow:

1) The wastewater enters the coagulation reactor and mixes evenly with a certain concentration of magnetic powder. Under the action of the coagulant and coagulant, the suspended solids and colloidal pollutants in the wastewater form magnetic flocs;

2) After the coagulation reaction, the effluent flows into the magnetic separation equipment. Under the high magnetic field strength, the magnetic flocs are absorbed by the disk and pulled out of the water to realize the separation of the magnetic flocs from the water.The effluent directly discharged;

3) The magnetic flocs separated from the magnetic disk are processed by the magnetic powder recovery system to realize the separation of magnetic substances and non-magnetic sludge. The separated magnetic powder continues to be recycled and the sludge enters the sludge disposal system;

4) The process of wastewater flowing into the coagulation reactor till the purification treatment of the magnetic separation equipment, the total residence time is about 3-5 minutes that the sewage can be quickly clarified.

The magnetic powder recovery rate is over 99%. The technical and economic advantages of the magnetic coagulation sedimentation process have been fully reflected.The technology has been more and more widely used worldly.

Working principle:

Ordinary suspended substance in the water is not magnetic.Magnetic flocculation technology impart non-magnetic suspended matter the magnetism, and then achieve liquid and solids seperation by rare earth disk seperator.

The sludge separated from the water is dispersed by the magnetic seed recovery system and separated from the magnetic powder after demagnetization. The magnetic seed enters the next recycling process。

Magnetic flocculation is that,in the process of flocculation,use magnetic flocculant to condensate and adsorb colloidal contaminants in the waste water.Due to the high density of magnetic flocculant,sludge precipitate instantly with low moisture,minimized the dewatering device and reduced the initial investment.This technology consumpts no or very small amount of chemicals.

Advantages:

 1) It has a good adsorption effect on bacteria, viruses, oil and various small particles.The removal effect is better than conventional.

2) HRT is short.The magnetic force is 640 times of gravity, and the magnetic separation is  over 10 times faster than gravity separation. It can separate pollutants from water quickly.It takes about 3 minutes for the suspension to separate from coagulation and reaction.

3) The sludege is approx 10% of conventional,results to cheaper dewatering cost.

4) Reduced land occupation.Capacity 1000 m³/h equipment need about 14x4 meter land.

5) Excellant effluent.The effluent SS ≤ 5 mg/L and TP <0.1 mg/L.

6) Low M&O cost.Power consumption is approx 0.06Khw/m^3.

7) Fabrication,commissioning and maintenance easy.It can be moved to another plant.