Sludge-water fast separating device and application thereof in biological sewage treatment

Abstract

The invention relates to a sludge-water fast separating device for fast separating clear liquid from the surface layer of turbulent flow and sludge mixed liquid and application thereof in biological sewage treatment. The sludge-water fast separating device is characterized in that a sludge-water separating assembly comprises partitioned vertical baffle plates and slag-stopping swash plates, wherein the slag-stopping swash plates are positioned on the peripheries of the partitioned vertical baffle plates; the sludge-water fast separating device is placed in a biological sewage treatment pond; the vertical baffle plates stabilize water flows and can achieve sludge-water separation by forming a thin clear liquid layer on the surface layer in a short time; the vertical surfaces of the surfaces of the partitioned vertical baffle plates are smooth without generating sludge accumulation, therefore microorganism adhesion is effectively prevented; the sludge-water fast separating device can save a second sedimentation pond and sludge external reflux when used inside the biological sewage treatment pond, thereby saving 50 percent of land occupation and 40 percent of civil engineering investment without being limited by solid loads of the traditional second sedimentation pond; the sludge concentration of the biological sewage treatment pond can achieve 7000-10000 mg / l, HRT (Hydraulic Retention Time)can be shortened to 1 / 2-1 / 3 of the traditional process, nominal retention time can be shortened by 40-60 percent, and operating cost is saved by more than 30 percent. The sludge-water fastseparating device disclosed by the invention can be used for the potential tapping and the expansion of the traditional system and enhances the system capability by more than 100 percent.

Description

technical field [0001] The invention relates to a mud-water rapid separation device for rapidly separating clear liquid on the surface layer of turbulent sludge mixed liquid, and its application in sewage biological treatment. Background technique [0002] Sewage biological treatment, such as municipal sewage activated sludge treatment, aims to remove suspended solids and dissolved biodegradable organic matter in sewage, and through the action of microorganisms, complete organic matter decomposition and biosynthesis, and transform organic pollutants into harmless Gas products (CO 2 ), liquid products (water) and solid products rich in organic matter (microbial groups or biological sludge), and then the excess biological sludge is separated from water and removed from the purified sewage. The purpose of mud-water separation is to separate the clear water for discharge, and the sludge still needs to be returned to the biological treatment tank to maintain the required activat...

AI Technical Summary

Problems solved by technology

At the same time, since the sedimentation sludge needs to be returned to the biological tank, it is not possible to promote sedimentation by adding chemicals (adding chemicals will affect the biological activity in the activated sludge system), and at the same time, there are often a large number of microorganisms in the biologically treated sewage, which is very easy to Attaching and growing biofilm in the inclined tube / inclined plate mud-water separation device with narrow channels will not only block the inclined plate / inclined tube after a long time, resulting in the failure of the separation function, and cannot achieve accelerated mud-water separation, but also in the inclined tube / inclined plate The growth of microorganisms dies, and after fermentation and gas production, it will also cause floating mud and affect the quality of effluent water. Therefore, inclined plate / inclined tube accelerated sedimentation devices are rarely used in subsequent sedimentation tanks for activated sludge treatment.

In this way, the separation of mud and water can only be achieved by natural settlement, so the area (volume) of the sedimentation tank is larger, resulting in a larger investment and land occupation.

[0004] Secondly, because the separation of sludge and water in the secondary sedimentation tank usually requires the effluent to be below 20mg / l, the solid load limits the sludge concentration of the incoming water to be below 3500-5000mg / l, which causes the sludge concentration in the activated sludge tank to also be limited to 3500 ~5000mg / l, can not be raised very high, so the concentration of activated sludge tank can not be raised normally

In order to achieve a higher biological treatment capacity, the residence time of sewage in the biological tank must be lengthened, which is also one of the reasons for the larger capacity of the activated sludge treatment tank.

[0005] Furthermore, a large amount of sludge returns after sedimentation in the secondary settling tank, which increases the energy consumption of the system operation and limits the reduction of treatment costs

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