Novel catalytic cracking flue gas desulfurization wastewater treatment device

Abstract

The invention discloses a novel catalytic cracking flue gas desulfurization wastewater treatment device, which is characterized by comprising a settler; the desulfurization wastewater is sent to the settler, wherein the settler sequentially comprises a clear water area, an inclined tube settling area and a concentration area from top to bottom; the wastewater enters the settler and then upwards enters the inclined tube settling area to complete mud-liquid separation, wherein the separated supernate enters a clear water area, and sludge sinks to a concentration area; the sludge concentration buffer tank is arranged below the settler, is communicated with the concentration area and is used for further settling sludge in the concentration area after the sludge is discharged into the concentration area; the dehydrator is arranged below the sludge concentration buffer tank and is used for dehydrating the sludge discharged from the sludge concentration buffer tank to form a sludge cake; and the oxidation tank is arranged below the settler, is communicated with the clear water area, and is used for discharging the supernatant in the clear water area to finish the oxidation of the supernatant. The settler is good in settling effect and can stably run for a long time, and the external drainage of the oxidation tank meets the SS index requirement.

Description

technical field [0001] The invention relates to a novel catalytic cracking flue gas desulfurization wastewater treatment device. Background technique [0002] The wastewater sent from the catalytic cracking desulfurization unit is first sent to the expansion drum filter for solid-liquid separation, and the separated thick slurry is discharged from the bottom of the expansion drum filter to the slurry buffer tank for concentration. After concentration, the solid content of the slurry increases to 10wt% to 20wt%, and then transported to the dehydrator for dehydration by the slurry pump. After dehydration by the dehydrator, the mud cake with a solid content of about 40% is transported to the factory by car for treatment. The supernatant of the slurry buffer tank and dehydrator is returned to the slurry buffer tank. The supernatant of the expansion drum filter enters the oxidation tank, through the oxidation air pipe and agitator installed in the oxidation tank, the air is used...

AI Technical Summary

Problems solved by technology

[0003] The SS (suspended solids) of the original desulfurization wastewater treatment unit cannot meet the standard stably. With the increasing environmental protection requirements, the SS index of the external drainage is required to be less than 50mg / L. The existing catalytic cracking flue gas desulfurization wastewater treatment device is difficult to meet the SS design. In addition, the difficulty in the treatment of catalytic cracking desulfurization wastewater is the removal of catalyst particles in the wastewater. The wet desulfurization process adopted by conventional power plants and boilers will also discharge desulfurization wastewater, but the suspended solids are mainly limestone, gypsum and smoke. better handling

However, the suspended solids in catalytic cracking regeneration flue gas desulfurization wastewater are catalyst particles, and the particle size of the catalyst particles is small, accounting for more than 80% of which are less than 5 μm, and the hardness of the particles is severe. The filter membrane is easily damaged during the process, which makes it difficult for the outlet SS to meet the standard. Therefore, the desulfurization wastewater treatment unit needs to be modified

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