Sequencing batch reactor for sewage treatment and sewage treatment system comprising same

Patent metadata

Field	Value
Publication number	US-2018297875-A1
Application number	US-201815953399-A
Country	US
Kind code	A1
Filing date	Apr 13, 2018
Priority date	Apr 18, 2017
Publication date	Oct 18, 2018
Grant date	—

Abstract

Disclosed is a sequencing batch reactor (SBR) for sewage treatment. The SBR is applicable to an energy-producing sewage treatment system. The SBR includes a treatment tank and a hybrid bacterial strain screening tank. The treatment tank removes ammonium contained in supernatant liquid using anaerobic ammonium-oxidizing (anammox) bacteria. The hybrid bacterial strain screening tank screen anammox bacteria granules out by passing the supernatant liquid discharged from the treatment tank through the hybrid bacterial strain screening tank. The SBR generates biogas using the anammox bacteria and reduces the nitrogen content in the supernatant liquid. The SBR can separate the anammox bacteria granules with high separation efficiency, thereby shortening sewage treatment time and recycling activated sludge, resulting in a dramatic decrease in the amount of waste sludge.

First claim

What is claimed is:

1 . A sequencing batch reactor (SBR) for sewage treatment, applicable to an energy-producing sewage treatment system, the SBR comprising a treatment tank and a hybrid bacterial strain screening tank as reaction tanks,
wherein the treatment tank removes ammonium contained in supernatant liquid by using anaerobic ammonium-oxidizing (anammox) bacteria, and wherein the hybrid bacterial strain screening tank filters the supernatant liquid discharged from the treatment tank by passing the supernatant liquid through a hybrid bacterial strain screening zone provided in the hybrid bacterial strain screening tank, to screen out ammonium-oxidizing bacteria granules.

2 . The sequencing batch reactor according to claim 1 , wherein the hybrid bacterial strain screening tank comprises:
a housing having a hybrid bacterial strain screening zone therein having a truncated circular conical shape; a feeding unit installed to extend through the housing and the hybrid bacterial strain screening zone, the feeding unit feeding the supernatant liquid to the hybrid bacterial strain screening zone; and a recovery unit for collecting and returning the supernatant liquid passing through the hybrid bacterial strain screening zone.

3 . The sequencing batch reactor according to claim 1 , wherein the hybrid bacterial strain screening zone has a truncated circular conical shape having an upper diameter larger than a lower diameter thereof so that the supernatant liquid introduced into the hybrid bacterial strain screening zone forms a vortex in the bacterial strain screening zone due to a difference between the upper diameter and the lower diameter, thereby swirling downward in the bacterial strain screening zone.

4 . The sequencing batch reactor according to claim 1 , wherein the hybrid bacterial strain screening zone includes a vortex-forming portion and a membrane, and the vortex-forming portion and the membrane are disposed respectively at an upper portion and a lower portion of the truncated circular conical shape.

5 . The sequencing batch reactor according to claim 4 , further comprising an anaerobic ammonium-oxidizing bacteria transport pipe such that anaerobic ammonium-oxidizing bacteria granules contained in the supernatant liquid introduced into the hybrid bacterial strain screening zone are screened out by the membrane and the anaerobic ammonium-oxidizing bacteria granules which are screened out are transported to the treatment tank through the anaerobic ammonium-oxidizing bacteria transport pipe.

6 . The sequencing batch reactor according to claim 4 , wherein the membrane has pores having a pore size between 50 and 150 μm.

7 . The sewage treatment sequencing batch reactor according to claim 1 , wherein activated sludge contains one or more species selected from the group consisting of ammonia oxidizing archaea (AOA), ammonia oxidizing bacteria (AOB), and nitrite oxidizing bacteria (NOB).

8 . The sequencing batch reactor according to claim 1 , wherein the anaerobic ammonium-oxidizing bacteria are planctomycetes.

9 . The sequencing batch reactor according to claim 1 , wherein the anaerobic ammonium-oxidizing bacteria are planctomycetes granules.

10 . A sewage treatment system comprising:
a primary settling tank in which pollutants in sewage settle to produce raw sludge and primary treated water; a bioreaction tank in which organic substances contained in the primary treated water discharged from the primary settling tank are adsorbed onto activated sludge to form a flock, the floc is removed, and a denitrification process is performed; a secondary settling tank in which waste sludge contained in biologically treated water discharged from the bioreaction tank is settled; a dehydration tank in which the raw sludge recovered from the primary settling tank and the waste sludge recovered from the secondary settling tank is dehydrated; a digestion tank in which the raw sludge and the waste sludge dehydrated in the dehydration tank undergoes a anaerobic digestion process, thereby generating biogas; and the sequencing batch reactor according to claim 1 , the sequencing batch reactor removing nitrogen contained in supernatant liquid discharged from the digestion tank.

11 . The sewage treatment system according to claim 10 , wherein the sequencing batch reactor comprises a hybrid bacterial strain screening tank for removing ammonium by reacting the supernatant liquid discharged from the digestion tank with anaerobic ammonium-oxidizing bacteria, and separating anaerobic ammonium-oxidizing bacteria granules contained in the supernatant liquid and activate sludge from each other.

12 . The sewage treatment system according to 11 , wherein the hybrid bacterial strain screening tank comprises:
a housing to have a hybrid bacterial strain screening zone of a truncated circular conical shape; a feeding unit installed to extend through the housing and the hybrid bacterial strain screening zone and to feed supernatant liquid to the hybrid bacterial strain screening zone; and a recovery unit to collect and return the supernatant liquid flowing through the hybrid bacterial strain screening zone.

13 . The sewage treatment system according to claim 12 , the hybrid bacterial strain screening zone includes a vortex-forming portion and a membrane, and the vortex-forming portion and the membrane are disposed respectively at an upper portion and a lower portion of the truncated circular conical shape

14 . The sewage treatment system according to claim 12 , wherein the hybrid bacterial strain screening tank further comprises a supernatant liquid feeding unit for transporting supernatant liquid containing activated sludge to the primary settling tank.

15 . The sewage treatment system according to claim 10 , wherein the activated sludge includes one or more species selected from the group consisting of ammonia oxidizing archaea (AOA), ammonia oxidizing bacteria (AOB), and nitrite oxidizing bacteria (NOB).

16 . The sewage treatment system according to claim 10 , wherein the bioreaction tank is equipped with an air feeder for feeding air such that organic substances in sewage are adsorbed onto the activated sludge.

17 . The sewage treatment system according to claim 10 , wherein the bioreaction tank includes a hybrid bacterial strain screening tank for separating the activated sludge onto which the organic substances are adsorbed.

18 . The sewage treatment system according to claim 10 , wherein the anaerobic ammonium-oxidizing bacteria are Planctomycetes.

19 . The sewage treatment system according to claim 10 , wherein the anaerobic ammonium-oxidizing bacteria are planctomycetes granules.

20 . The sewage treatment system according to claim 10 , further comprising a biogas collector for collecting biogas generated from the digestion tank.

Assignees

• Doosan Heavy Ind & Construction Co Ltd

Inventors

• Cho Hwan Chul
• Kim Seong Ju
• Jin Yang Oh
• Lee Chul Woo

Classifications

• C02F1/001

  Processes for the treatment of water whereby the filtration technique is of importance (C02F1/44 takes precedence; construction of filters in general B01D24/00 - B01D41/00) · CPC title

• C02F2101/166

  Nitrites · CPC title

• C02F3/348

  characterised by the way or the form in which the microorganisms are added or dosed · CPC title

• C02F11/04

  Anaerobic treatment; Production of methane by such processes · CPC title

• C02F3/20

  using diffusers · CPC title