Method for treating high-concentration wastewater produced by refining technology

Abstract

The invention discloses a method for treating high-concentration wastewater produced by a refining technology. The method comprises the following steps: firstly, high-concentration wastewater enters a mechanical drum screen to remove solid-phase waste in the wastewater; then, the wastewater without the solid-phase waste flows into a circulating water tank and enters a flat composite membrane group treatment pile through a pump group to remove the slurry and oil in the wastewater; and finally, the purification is finished to obtain recyclable water, and the recyclable water enters a recyclable water tank. The method disclosed by the invention has the following advantages: the mechanical drum screen can intercept the solid-phase matters bigger than 5-100mu m in the wastewater, so that the requirement on the suspended solids entering a right-angle filter is raised, and the efficiency of the system equipment is improved; and meanwhile, since a large quantity of solid-phase matters are intercepted, the load on follow-up processing is relieved, the energy saving is facilitated, and the exception handling ability of equipment is enhanced.

Description

technical field [0001] The invention relates to a method for treating wastewater, in particular to a method for treating high-concentration wastewater produced in a scouring process. Background technique [0002] During the refining production process of textile printing and dyeing enterprises, a large amount of discharged wastewater will be generated. The source of wastewater is mainly pretreatment wastewater and washing wastewater. The main pollutants of pretreatment wastewater and washing wastewater are emulsified oil, surfactant, chemical slurry, etc. Among them, the BOD content is low, the COD is about 5000-50000PPM, and the PH is high. The pollutants of this type of wastewater adopt general biochemical processes, which are difficult to degrade and have a long residence time for biochemical treatment. Generally, the following biochemical process steps are used. Treatment: Pre-treatment wastewater enters the grille, regulating tank, demulsification, secondary gas source,...

AI Technical Summary

Problems solved by technology

[0002] During the refining production process of textile printing and dyeing enterprises, a large amount of discharged wastewater will be generated. The source of wastewater is mainly pretreatment wastewater and washing wastewater. The main pollutants of pretreatment wastewater and washing wastewater are emulsified oil, surfactant, chemical slurry, etc. Among them, the BOD content is low, the COD is about 5000-50000PPM, and the PH is high. The pollutants of this type of wastewater adopt general biochemical processes, which are difficult to degrade and have a long residence time for biochemical treatment. Generally, the following biochemical process steps are used. Treatment: Pre-treatment wastewater enters the grille, regulating tank, demulsification, secondary gas source, degradation in contact oxidation tank, sedimentation tank, electro-oxidation tower, and discharges up to the standard. The discharge from the secondary gas source is air-floated sludge. The washing water directly enters the contact oxidation tank for degradation, and then enters the subsequent process. The solids formed in the sedimentation tank and the air-floated sludge are solidified and dehydrated. The solids can also be acidolyzed. Part of the wastewater treated by the electro-oxidation tower It can be refluxed as water for air flotation sludge, and the drainage can meet the GB4287-2012 first-level discharge standard through the above treatment process: COD is less than or equal to 80mg / l, BOD is less than or equal to 20mg / l, SS is less than or equal to 50mg / l, PH6~9, but In this treatment method, due to the presence of organic emulsified oil and surfactant in the wastewater, it is difficult to degrade it by general biochemical oxidation process, so the process of demulsification and flotation is used in the process to remove about 70-80% of the wastewater. COD is then treated in the biological oxidation tank. The process is long and the treatment process is complicated. If the control is abnormal, it is easy to exceed the standard, and the treated discharge water is not considered for reuse, and the utilization of water resources is not very sufficient.

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