Dyeing and printing waste clearing, synthetic wastewater advanced treatment circulation production and recycle technique

Abstract

The invention discloses a deep treatment technique used for the printing and dyeing sewage recovery. The technique consists of a BAF pond, an air-bearing system, an ozone contact oxidation tower, a filter, an active carbon filter, an ozone generator and a medicine adding system. The technique is the improvement of the traditional BAF technique, removes the resolvable organism in the sewage through the biological degradation, outtakes the water into the air-bearing system and combines the flocculation medicine adding technique, so as to eliminate the non-solvent organism and colloidal substance in the sewage. The outtaken water enters into the ozone contact oxidation tower and gets mixed with ozone, so that the organism which is difficult to undergo the biological degradation in the printing and dyeing sewage is removed with the help of the strong oxidizing property of the ozone. The water flowing out of the ozone contact oxidation tower enters into the pond at the middle, and 30 percent of the water returns to a gas dissolving can under the action of a pressurizing pump, gets mixed with the pressurized air and then enters into the air-bearing system through utilizing the remaining pressure. The gas-water solution is dispersed into the small and equable drips through a dissolved gas releaser, and the drips drive the suspending substances and the colloidal substance to float up to the water surface so as to achieve the removal. The water coming out of the middle pond enters into the filter to remove the small suspending substances and enters into the ozone / active carbon filtering system so that the reaction of the ozone basic chain is caused under the action of the active carbon, thereby speeding up the decomposition of the ozone into OH and other free radicals, degrades a small amount of organism, eliminates the color and finally ensures that the outtaken water reaches the recovery standard of the printing and dyeing sewage.

Description

technical field [0001] The invention relates to a process for printing and dyeing waste water and comprehensive waste water that has been treated to a certain standard through advanced treatment and recycling, specifically refers to the process of printing and dyeing comprehensive waste water that has been treated to meet the "Discharge Standards for Water Pollutants in Textile Dyeing and Finishing Industry" (GB4287 -92) The waste water of the first or second discharge standard, or a part of the waste water with a cleaner appearance after the cleaning and diversion, can be recycled to the printing and dyeing wastewater advanced treatment process in the printing and dyeing process. Background technique [0002] my country has less water resources, more and more serious water pollution, and the current situation that requires sewage resource utilization. Printing and dyeing wastewater is a large source of water for industrial production, so treatment and reuse has become very i...

AI Technical Summary

Problems solved by technology

[0009] 1. The accumulation of organic pollutants, because it is impossible for any sewage treatment system to remove all pollutants. If it is recycled for a long time, this part of the pollutants that are difficult to remove will accumulate in the circulation system

Accumulated to a certain extent, it will make the sewage treatment system unable to operate

[0010] 2. The accumulation of inorganic salts. The sewage treatment system cannot remove inorganic salts. If the reuse rate is too high and desalination treatment is not carried out, the salts in the system will accumulate to a very high level, making production and sewage treatment impossible.

[0012] 1. Conventional sewage reuse is mostly a coagulation sedimentation filtration process. There is no strong oxidant in this process, which cannot remove the refractory biodegradable organic matter remaining in the sewage, and cannot remove the solute chroma in the water

[0013] 2. After secondary treatment, domestic sewage is mostly impurities with small particle size and low density, which increases the difficulty of treatment by precipitation process

[0014] 3. Due to the slow settling speed of flocs, this process has the problems of long residence time and large floor area, which increases the cost of infrastructure and maintenance

[0015] 4. At present, the conventional recycling water process adopts chlorine disinfection method, which will introduce irritating odor into the effluent water, thereby reducing the water quality of the effluent water, and will also bring by-products harmful to humans and animals such as: chloroform, chlorine Vinyl, etc.

[0016] 5. The high moisture content of the sediment in the coagulation and sedimentation process not only reduces the water yield, but also makes it difficult to treat the sediment

[0017] 6. The filtration process can only remove SS, turbidity, and surface chroma in wastewater, but cannot remove refractory organic matter and soluble chroma in wastewater

[0018] 7. Membrane treatment is currently the most commonly used advanced treatment process at home and abroad, but the effluent after membrane treatment is acidic, and the pH of printing and dyeing water is between 7.3-7.8, so the effluent is not suitable for printing and dyeing water, and membrane treatment requires pretreatment It is very high, and the SDI value is less than 4 to ensure the normal use of the membrane. There are disadvantages such as high total investment, high operating cost, unstable operation, frequent membrane replacement, and troublesome management.

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