Device for eliminating float sludge in sludge sedimentation tank of sewage treatment system

Abstract

The utility model relates to the technical field of sewage treatment systems, in particular to a device for eliminating float sludge of a sludge sedimentation tank of a sewage treatment system, which comprises a contact oxidation tank, a flocculation tank, a stirrer, the sludge sedimentation tank and a sludge reflux pump, the contact oxidation tank is arranged in front of the flocculation tank, the flocculation tank is arranged in front of the sludge sedimentation tank, and the stirrer is arranged in front of the sludge sedimentation tank. The contact oxidation tank is provided with an overflow hole I, the flocculation tank is provided with an overflow hole II, the contact oxidation tank overflows sewage into the flocculation tank through the overflow hole I, the flocculation tank overflows sewage into the sludge reflux tank through the overflow hole II, the overflow hole I is higher than the overflow hole II, and three sludge reflux pumps are arranged in the sludge sedimentation tank. An inlet pipeline of each sludge reflux pump is arranged in the sludge sedimentation tank, and an outlet pipeline is arranged at the front end of the contact oxidation tank. The device has a good effect of eliminating the floating sludge of the sludge sedimentation tank, so that the effluent of the sludge sedimentation tank is clear, suspended matters are greatly reduced, and the chemical oxygen demand contained in the discharged water is stable and qualified.

Description

Technical Field

[0001] The utility model relates to the technical field of sewage treatment systems, in particular to a device for eliminating floating sludge in a sludge sedimentation tank of a sewage treatment system. Background Art

[0002] In the methanol-to-ethanol fuel process, the sewage treatment plant treats all biodegradable wastewater generated by the polyoxymethylene dimethyl ether production plant, including three major parts: the flue gas scrubber and air scrubber from the formaldehyde plant, the bottom wastewater from the methylal reaction tower from the methylal plant, and the salt-containing wastewater discharged from the trioxymethylene plant after desalination treatment by the salt-containing wastewater treatment plant (evaporation and crystallization).

[0003] The primary function of the sludge sedimentation tank in a sewage treatment system is to concentrate the mixed liquor from the contact oxidation tank through gravity settling, thereby concentrating the sludge and separating the supernatant. Currently, the sludge sedimentation tanks used in sewage treatment systems feature a stepped bottom with no vertical slope and no sludge storage tanks. Therefore, when designing for single-pump return or sludge discharge, sludge flow is limited to a 1-meter radius around the pump. The 5.4-meter-long sludge sedimentation tank has a blind spot for concentrated sludge return or discharge. The activated sludge accumulates at the bottom of the sedimentation tank due to decomposition, turning black and generating bubbles due to self-decomposition. Due to the low porosity of the decomposed sludge, bubbles accumulate within the tank. When the overall density of the decomposed sludge is lower than that of water, the bubbles rise to the surface and are discharged to the next level via the overflow weir of the sedimentation tank. This results in increased suspended matter and color at the discharge outlet, and significant fluctuations in the chemical oxygen demand (COD) content of the water. This seriously impacts the effluent quality, rendering the discharged water substandard and failing to meet safety and environmental protection requirements. Utility Model Content

[0004] The utility model aims to solve the above problems and provides a device for eliminating floating sludge in a sludge sedimentation tank of a sewage treatment system.

[0005] The utility model is realized through the following technical scheme: a device for eliminating floating sludge in a sludge sedimentation tank of a sewage treatment system, characterized in that it comprises a contact oxidation tank, a flocculation tank, a stirrer, a sludge sedimentation tank and a sludge return pump, wherein the contact oxidation tank is arranged before the flocculation tank, and the flocculation tank is arranged before the sludge sedimentation tank, an overflow hole 1 is provided on the contact oxidation tank, and an overflow hole 2 is provided on the flocculation tank, the contact oxidation tank overflows sewage to the flocculation tank through the overflow hole 1, and the flocculation tank overflows sewage to the sludge return tank through the overflow hole 2, wherein the overflow hole 1 is higher than the overflow hole 2, and three sludge return pumps are provided in the sludge sedimentation tank, the inlet pipe of each sludge return pump is arranged in the sludge sedimentation tank, and the outlet pipe is arranged at the front end of the contact oxidation tank.

[0006] Furthermore, a partition is provided in the middle of the flocculation tank, and two mixers are provided on the flocculation tank.

[0007] Furthermore, the three sludge return pumps include a left sludge return pump, a middle sludge return pump, and a right sludge return pump, which are respectively arranged at 1 / 4, 1 / 2, and 3 / 4 of the longitudinal center line of the sludge return tank.

[0008] The beneficial effects of the utility model are as follows: the utility model configures a sludge return pump on the left, middle and right sides of the sludge sedimentation tank, so that the activated sludge settled in the sludge sedimentation tank can be returned or discharged in time; the activated sludge does not accumulate at the bottom of the sludge sedimentation tank and decompose and float up, thereby eliminating black floating sludge, improving the water quality of the external drainage and stably discharging it to meet the process requirements.

[0009] The utility model has a good effect of eliminating floating sludge in the sludge sedimentation tank, making the effluent from the sludge sedimentation tank clear and the suspended matter greatly reduced, and the chemical oxygen demand contained in the external drainage is stable and qualified, thereby improving the sewage quality and achieving the purpose of safety and environmental protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a structural diagram of the present utility model.

[0011] In the attached drawings, 1 is a contact oxidation tank, 11 is an overflow hole 1, 2 is a flocculation tank, 21 is a partition, 22 is an overflow hole 2, 3 is a mixer, 4 is a sludge sedimentation tank, and 5 is a sludge return pump. DETAILED DESCRIPTION

[0012] In order to make the purpose, technical solution and beneficial effects of the present invention more clear, the technical solution of the present invention is further described below in conjunction with embodiments.

[0013] like Figure 1 As shown, a device for eliminating floating sludge in a sludge sedimentation tank 4 of a sewage treatment system includes a contact oxidation tank 1, a flocculation tank 2, a mixer 3, a sludge sedimentation tank 4 and a sludge return pump 5. The contact oxidation tank 1 is arranged before the flocculation tank 2, and the flocculation tank 2 is arranged before the sludge sedimentation tank 4. The contact oxidation tank 1 is provided with an overflow hole 1, and the flocculation tank 2 is provided with an overflow hole 2. The contact oxidation tank 1 overflows sewage into the flocculation tank 2 through the overflow hole 1, and the flocculation tank 2 overflows sewage into the sludge return tank through the overflow hole 2, wherein the overflow hole 1 is higher than the overflow hole 2. Three sludge return pumps 5 are provided in the sludge sedimentation tank 4, and the inlet pipe of each sludge return pump 5 is arranged in the sludge sedimentation tank 4, and the outlet pipe is arranged at the front end of the contact oxidation tank 1. The three sludge return pumps 5 include a left sludge return pump 5, a middle sludge return pump 5, and a right sludge return pump 5, which are respectively arranged at 1 / 4, 1 / 2, and 3 / 4 of the longitudinal center line of the sludge return tank.

[0014] A partition 21 is provided in the middle of the flocculation tank 2, and the height of the partition 21 is lower than the wall of the flocculation tank 2. Two mixers 3 are provided on the flocculation tank 2. The partition 21 divides the flocculation tank 2 into two areas, that is, the sewage overflows from the front area of the flocculation tank 2 to the rear area through the partition 21. The overflow hole 2 is correspondingly arranged on the wall of the flocculation tank 2 in the rear area. The position of the overflow hole 2 is lower than the height of the partition 21. The two mixers 3 are respectively set in the front area and the rear area.

[0015] During use, the sewage in the contact oxidation tank 1 first overflows to the front area of the flocculation tank 2 through the overflow hole 1, overflows to the rear area of the flocculation tank 2 through the partition 21 in the front area, and overflows into the sludge sedimentation tank 4 through the overflow hole 2 in the rear area of the flocculation tank 2. After settling in the sludge sedimentation tank 4, the unsettled activated sludge is sucked into the contact oxidation tank 1 by the sludge return pump 5 for further treatment, and the cycle continues.

[0016] Except for the technical features described in the specification, the remaining technical features are known to those skilled in the art.

Claims

1. A device for removing floating sludge from a sludge sedimentation tank in a sewage treatment system, characterized in that: The invention comprises a contact oxidation tank (1), a flocculation tank (2), a mixer (3), a sludge sedimentation tank (4) and a sludge return pump (5), wherein the contact oxidation tank (1) is arranged before the flocculation tank (2), and the flocculation tank (2) is arranged before the sludge sedimentation tank (4), the contact oxidation tank (1) is provided with an overflow hole 1, and the flocculation tank (2) is provided with an overflow hole 2, the contact oxidation tank (1) overflows sewage to the flocculation tank (2) through the overflow hole 1, and the flocculation tank (2) overflows sewage to the sludge return tank through the overflow hole 2, wherein the overflow hole 1 is higher than the overflow hole 2, and three sludge return pumps (5) are arranged in the sludge sedimentation tank (4), the inlet pipe of each sludge return pump (5) is arranged in the sludge sedimentation tank (4), and the outlet pipe is arranged at the front end of the contact oxidation tank (1).

2. The device for removing floating sludge from a sludge sedimentation tank in a sewage treatment system according to claim 1, characterized in that: A partition (21) is provided in the middle of the flocculation tank (2), and two stirrers (3) are provided on the flocculation tank (2).

3. The device for removing floating sludge from a sludge sedimentation tank in a sewage treatment system according to claim 1, characterized in that: The three sludge return pumps (5) include a left sludge return pump (5), a middle sludge return pump (5), and a right sludge return pump (5), which are respectively arranged at 1 / 4, 1 / 2, and 3 / 4 of the longitudinal center line of the sludge return tank.

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