Method for directly and deeply purifying high concentration organic wastewater

A method for directly purifying organic wastewater, comprising steps of:

• (1) fortified precipitation treatment:
• sending the organic wastewater to an enhanced precipitation unit for pretreatment, wherein the enhanced precipitation unit comprises a dosing and coagulation unit, a dosing and flocculation unit and a physical precipitation unit;
• (2) filtration of sediment of suspended solids:
• passing the organic wastewater treated by the enhanced precipitation unit through a filtration unit for the sediment of the suspended solids, wherein a filter material of the filtration unit for the sediment of the suspended solids is selected from the group of gravel, river sand, and combinations thereof, and particle size distribution of a filter bed comprises:
• 2-4 cm of a surface layer, 1-2 cm of a middle and upper layer, and 0.5-1 cm of a lower layer;
• (3) pH adjustment:
• performing alkalinity adjusting pretreatment on the organic wastewater after the filtration of the sediment of the suspended solids in the step (2) and adjusting a pH value of the organic wastewater to a range of 7.5-10.5;
• (4) hydrolysis acidification:
• introducing the organic wastewater after adjusting the pH value into a water distribution unit, and a biological membrane packing is provided in the water distribution unit to strengthen anaerobic hydrolysis acidification effects of the organic wastewater;
• (5) treatment of a bio-filter:
• distributing the organic wastewater into a bio-filter unit by the water distribution unit, so as to achieve direct treatment of the organic wastewater by organic matter degradation ability of biological filler;
• wherein in the step (5), a height of the bio-filter adopted in the step (5) is at a range of 2.0 to 3.5 meters, and is divided into 5 to 10 layers from top to bottom, comprising:
• a top water distribution layer, a secondary water distribution layer, and an intermittent water distribution layer, a gas-water backwashing layer, a bottom water collecting layer, and a blind drain sewage layer;
• a top cloth water layer is provided overheadly with an atomizing water distributor, and an atomizing nozzle is provided on the atomizing water distributor;
• a distance between the secondary water distribution layer and a top of the bio-filter is at a range of 15-25 cm;
• and a diameter of a water distribution pipe of the secondary water distribution layer is ½ of a diameter of a water distribution pipe of the top water distribution layer;
• the gas-water backwashing layer comprises 5 layers, wherein each layer of the 5 layers is 0.1 m;
• and backwashing water pipes and backwashing gas pipes are staggered inside the gas-water backwashing layer;
• sand is provided between each adjacent layer of the 5 layers for serving as partition layers;
• the bottom water collecting layer is made of plastic blind ditch, perforated PVC water pipe or perforated PE water pipe, which are provided in a branch shape.

A method for directly purifying organic wastewater, comprising steps of:

• (1) fortified precipitation treatment:
• sending the organic wastewater to an enhanced precipitation unit for pretreatment, wherein the enhanced precipitation unit comprises a dosing and coagulation unit, a dosing and flocculation unit and a physical precipitation unit;
• (2) filtration of sediment of suspended solids:
• passing the organic wastewater treated by the enhanced precipitation unit through a filtration unit for the sediment of the suspended solids, wherein a filter material of the filtration unit for the sediment of the suspended solids is selected from gravel, river sand, and combinations thereof, and particle size distribution of a filter bed comprises:
• 2-4 cm of a surface layer, 1-2 cm of a middle and upper layer, and 0.5-1 cm of a lower layer;
• (3) pH adjustment:
• performing alkalinity adjusting pretreatment on the organic wastewater after the filtration of the sediment of the suspended solids in the step (2) and adjusting a pH value of the organic wastewater to a range of 7.5-10.5;
• (4) hydrolysis acidification:
• introducing the organic wastewater after adjusting the pH value into a water distribution unit, and a biological membrane packing is provided in the water distribution unit to strengthen anaerobic hydrolysis acidification effects of the organic wastewater;
• (5) treatment of a bio-filter:
• distributing the organic wastewater into a bio-filter unit by the water distribution unit, so as to achieve directly treatment of the organic wastewater by organic matter degradation ability of biological filler;
• wherein a coagulant adopted in the dosing and coagulation unit in the step (1) comprises:
• polyaluminum chloride or polyferric ferrous sulfate;
• a flocculating agent adopted in the dosing and flocculation unit comprises cationic polyacrylamide, anionic polyacrylamide or nonionic polyacrylamide;
• wherein the dosing and flocculation unit specifically adopts a mechanical flocculation tank, a first flocculation time is at a range of 20-30 min, and a flow velocity of the mechanical flocculation tank is designed according to a gradient from large to small, and a starting flow velocity is at a range of 0.5-0.6 m/s, and an end flow velocity is at a range of 0.2-0.3 m/s, and a clearance between partitions is greater than 0.5-1 m.