NOVELTY - Printing and dyeing sewage is recycled by removing non-anaerobic impurities and sand in primary settling tank; discharging sewage into a full-closed anaerobic tank and into a flocculating tank, adding flocculant, and precipitating; discharging into an oxidizing channel, and then into a coagulating tank and adding coagulant; precipitating and feeding supernatant fluid into a photocatalysis oxidizing tank; adding flocculant and decoloring agent; sand filtering; feeding into a modified active carbon absorbing device; sterilizing; and absorbing recycled water with active carbon.    USE - Method for recycling the printing and dyeing sewage.    ADVANTAGE - Quality of the treated water reaches the standard of printing and dyeing technique, which saves a large amount of water and obtains economical and environmental benefits. The biogas from sewage treatment is collected for power generation, thus ensuring self running of the system. The sludge is taken as fuel for boiler, thus saving running cost for printing and dyeing enterprise and avoiding secondary pollution caused by garbage landfill.    DETAILED DESCRIPTION - Recycling the printing and dyeing sewage comprises: (A) removing non-anaerobic impurities and sand in primary settling tank; (B) discharging treated sewage into a full-closed anaerobic tank with multiple baffling plates inside to ensure enough flowing time for sewage, where retention of sewage in anaerobic tank is 20-40 hours, the chemical oxygen demand (COD) removing rate in discharged water is over 70% and pH value is 6.5-8.0, where top of anaerobic tank is connected with a biogas storage tank which is also connected with a biogas power generator via a pipeline, and the power supplied from biogas power generator is provided to whole sewage treatment system; (C) discharging treated sewage into a flocculating tank and adding flocculant and flocculation additive to remove the COD and biological oxygen demand (BOD) chromaticity in the sewage, and precipitating; (D) discharging the sewage into an oxidizing channel, using a diving aerator and an injecting aerator till the ratio of water to gas reaches 1: 10 to 1: 30 to create a good survival condition for aerobic bacteria for high-efficiency oxidization of oxidizing channel; rotating the sewage in the oxidizing channel for 5-6 hours with effect of plug flow device and reducing part of COD and BOD with effect of aerobic bacteria flora, where the nitrogen, phosphorus and potassium contents reach the national discharge standard during the aerobic treatment, where the COD, BOD, pH value are respectively 100, 30 and 6.5-7 mg/L, and the chromaticity is below 100 times, thus the water is free from eutrophication; (E) discharging the sewage into a coagulating tank, adding coagulant to further remove the suspension and fine particles from sewage, promote the flocculating speed and shorten the settling time, where contents of solid suspension (SS) and ammonia nitrogen respectively reach 10-20 mg/L and 8-12 mg/L, thus reaching the standard of primary treatment to recycled water and setting up a foundation for deep treatment; (F) precipitating the sewage to obtain supernatant fluid, then feeding the supernatant fluid into a photocatalysis oxidizing tank for photocatalysis oxidization, thus further removing the residual COD, BOD, ammonia, nitrogen and phosphorus in effects of photocatalysis oxidizing, bio-bacteria and alga; (G) adding flocculant and decoloring agent into the recycled water after photocatalysis oxidization, reducing all the solid and chromaticity to a deep treatment standard with contents of COD, BOD, SS and chromaticity below 70 mg/L, 20 mg/L, 10 mg/L and 30 times and other standards reaching the national index CECS6I-1994; (H) mechanically filtering the recycled water in a sand filter to remove suspension, floater and precipitate for further improving the quality of treated recycled water; (I) feeding the sand filtered recycled water into a modified active carbon absorbing device, where the modified active carbon particle is small with many pores inside and large body surface area, thus absorbing and decoloring water strongly, which effectively removes organic substances from the printing and dyeing wastewater and improves the water quality to standard recycled water; (J) sterilizing the recycled water to oxidize the COD, BOD sulfide and other solutes, strongly oxidizing all the residues and further oxidizing heavy metal, chloride and sulfide and killing the bacteria, thus improving quality of recycled water to the domestic multi-purpose water quality standard CJ 25. 1-89 and regenerative recycled water quality standard CECS61-1994; and (K) absorbing the recycled water with active carbon, then finally treating the dyeing material and solute after primary treatment, where the active carbon decolors well, and further removing the non-dissolvable light yellow and particular small in the primary treatment to improve the water quality to meet the printing and dyeing standard.    DESCRIPTION OF DRAWING(S) - The drawing is a block diagram of a method for recycling printing and dyeing sewage resource (Drawing includes non-English language text).