SU1699945A1 - Secondary settler of sewage biological treatment system - Google Patents

Abstract

The proposal relates to sanitary engineering and can be used in the biological treatment of wastewater. The purpose of the invention is to increase the cleaning efficiency by improving the quality of the circulating activated sludge while reducing the removal of its particles with the water being cleaned. The goal is achieved by dividing the settling chamber into two sections, in the first of which you see circulating activated sludge in the sediment, and in the second - excess, discharged separately. This makes it possible to reduce the settling time in oxygen starvation regimes of the circulating sludge to increase its quality, to increase the time of settling of the excess sludge to reduce its removal with purified water into the water bodies. 1 hp ff. 3 il.

Description

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The invention relates to sanitary engineering and can be used for the biological treatment of wastewater.

The purpose of the invention is to increase the efficiency by improving the quality of the circulating activated sludge while simultaneously reducing the removal of its particles from the sump with purified water.

Figure 1 shows the sump, a longitudinal section; figure 2 - part of the sump from the inlet side of the source water; on fig.Z - transverse section of the sump.

The sump contains a housing 1 with a supply pipe 2, a redistributor 3 of a mixture of purified waste water with activated sludge over the cross section of the sump, a sump chamber and sludge dust 4, collecting tray 5 with a discharge pipe 6 on the opposite side of the sump, pipelines 7 and 8 circulating and excess activated sludge, the second

Sludge at bottom 9, Rib 10 in the bottom divides the settling chamber into two sections 11 and 12 with the opposite direction of the slopes of their bottoms 13 and 14. The plate 15 above the bottom of the power unit 16 is connected by a pipeline 17 with a pipeline of circulating activated sludge.

The sump works as follows.

Purified wastewater with activated sludge is fed into the housing 1 through the redistributors 3 into the first section 11 of the settling tank, in which predominantly higher quality activated sludge is deposited at an increased rate. This makes it possible to significantly reduce the residence time of the circulating sludge in oxygen starvation regimes in the sump, and thereby maintain its high quality. This cannot be achieved in the secondary settling tanks of well-known cones.

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because of the need to retain low-quality sludge, which requires a multiple increase in the time of settling. The precipitated circulating sludge is displaced by known methods into its location at 4, from where it returns via the pipeline 7 to the aeration tank to continue the purification of new wastewater inflows.

The remaining lower quality surplus sludge enters with the water from section 11 to section 12 of the settler, and the sedimentation process continues. Since, due to the absence of circulating sludge in this section, the settling time can be significantly increased, it is also possible to improve the quality of the clarification due to more complete separation of the sludge from the treated wastewater. Excess sludge is shifted to its location at IC 9 and then piped 8 is diverted for further processing by one of the known Methods.

To further reduce the residence time of the circulating sludge in the settling basin, the first section performs two tiers to reduce the length of the settling path that is in the upper layers of the settling sludge settling tank, which flows to the slab 15, during the washing 16 and through the overflow tpy6onpOBOfl 17 into the circulating sludge pipeline 7.

The invention makes it possible to increase the quality of the circulating active sludge due to the separation from the excess sludge directly in the settling tank and due to the shortening and time of its stay in the Deposition modes. This reduces the time of its oxygen starvation — that is, the composition of the circulating sludge and the conditions for its settling simultaneously improve. Since excess sludge is settled separately in

another section after separation of the circulating sludge — the limitations on the total settling time are removed, which, without compromising the quality of the circulating sludge, can be significantly increased to drastically reduce the removal of sludge from the sedimentation tank with purified water.

Claims (2)

1. The secondary settling tank of the biological wastewater treatment system, comprising a housing with a supply water supply pipe and a redistributor, a settling chamber with sludge dust, collecting tray with discharge pipe of clarified water, circulating and excess sludge pipelines, characterized in that, in order to improve efficiency by improving the quality circulating activated sludge with a simultaneous decrease in the removal of its particles from the sump with treated water, it is equipped with additional sludge dust made in the bottom of the sump housing from the side of the discharge pipe, as well as with an edge installed on the bottom of the settling chamber and dividing it into two sections, the bottoms of the sections are made with the opposite slope to their nails, with By this, the circulating sludge pipeline is connected to the main stream, and the excess sludge pipeline to the additional sediment stream. 2. The sump according to claim 1, that is, it is equipped with a plate placed above the bottom of the first section of the settling chamber with a slope to the main tank, and also attached to the plate with sludge dust, with overflow pipeline attached to the circulating sludge pipeline. T J 13 wfldltsii " FIG. 2 12 L 1 11 V  2 / / eight 9- / B: x .J