Coupling bioreactor and method for purifying malodorous gases and wastewater

Patent metadata

Field	Value
Publication number	US-9561976-B2
Application number	US-201313911066-A
Country	US
Kind code	B2
Filing date	Jun 5, 2013
Priority date	Oct 10, 2012
Publication date	Feb 7, 2017
Grant date	Feb 7, 2017

Abstract

A coupling bioreactor in the form of a tower type seal structure filled with a suspended carrier. A water inlet pipe, an air inlet pipe, and a first microporous aerator are arranged at the bottom of the coupling reactor. The water inlet pipe is connected to a water distributor. The air inlet pipe is connected to the first microporous aerator. A gas inlet pipe and a second microporous aerator are arranged at the middle part of the coupling bioreactor and are connected with each other. An annular overflow weir is arranged at the upper part of the coupling bioreactor and is connected to a water outlet pipe. A gas outlet pipe is arranged at the top of the coupling bioreactor. The ratio of the height to the diameter of the coupling bioreactor is between 3 and 10.

First claim

The invention claimed is:

1. A coupling bioreactor for treating malodorous gas and wastewater simultaneously, the coupling bioreactor being in the form of a tower type seal structure, and the coupling bioreactor comprising:
a) a water inlet pipe;
b) an air inlet pipe;
c) a gas inlet pipe;
d) a first and a second microporous aerator;
e) a water distributor;
f) a suspended carrier;
g) a gas outlet pipe;
h) a water outlet pipe;
i) an annular overflow weir, the annular overflow weir comprising an annular sidewall and an annular groove;
j) a biofilm; and
k) a net cover, the net cover being in a disc shape and comprising a circular edge;

wherein:
the coupling bioreactor is filled with the suspended carrier;
the biofilm is attached to the suspended carrier;
the suspended carrier is a polyethylene;
a ratio of a volume of the suspended carrier to a capacity of the coupling bioreactor is between 30% and 50%;
a ratio of a height to a diameter of the coupling bioreactor is between 3 and 10;
the water inlet pipe is adapted to receive wastewater;
the gas inlet pipe is adapted to receive malodorous gas;
the water inlet pipe, the air inlet pipe, and the first microporous aerator are arranged at a bottom of the coupling bioreactor; the water inlet pipe is connected to the water distributor; the air inlet pipe is connected to the first microporous aerator;
the gas inlet pipe and the second microporous aerator are arranged at a middle part of the coupling bioreactor and are connected with each other;
the annular overflow weir is arranged at an upper part of the coupling bioreactor and is connected to the water outlet pipe;
the circular edge is connected to a top edge of the annular sidewall;
the gas outlet pipe is arranged at a top of the coupling bioreactor; and
when in use, when the malodorous gas and wastewater are introduced into the coupling bioreactor, the suspended carrier moves randomly in the coupling bioreactor.

2. The coupling bioreactor of claim 1 , wherein the first microporous aerator and the second microporous aerator are disc type membrane microporous aerators.

3. The coupling bioreactor of claim 2 , wherein a density of the suspended carrier before a biofilm formation is between 0.97 and 0.98 g/cm 3 ; and a density of the suspended carrier after the biofilm formation is 1 g/cm 3 .

4. The coupling bioreactor of claim 1 , wherein when an initial concentration of odorous compounds in the malodorous gas is less than 320 mg/m 3 , the ratio of the height to the diameter of the coupling bioreactor is between 3 and 6; the odorous compounds comprise ammonia and hydrogen sulfide.

5. The coupling bioreactor of claim 1 , wherein when an initial concentration of odorous compounds in the malodorous gas is between 320 and 620 mg/m 3 , the ratio of the height to the diameter of the coupling bioreactor is between 7 and 10; the odorous compounds comprise ammonia and hydrogen sulfide.

6. The coupling bioreactor of claim 1 , wherein the ratio of the height to the diameter of the coupling bioreactor is dependent on an initial concentration of odorous compounds in the malodorous gas; the odorous compounds comprise ammonia and hydrogen sulfide.

7. A method for purifying malodorous gas and wastewater using the coupling bioreactor of claim 1 , the method comprising:
1) introducing the wastewater through the water inlet pipe and the water distributor into the coupling bioreactor;
2) introducing air through the air inlet pipe and the first microporous aerator into the coupling bioreactor in the form of microbubbles; controlling an aeration rate for maintaining a dissolved oxygen concentration in the coupling bioreactor between 2 and 6 mg/L; and allowing the air and the wastewater to flow up synchronously;
3) introducing the malodorous gas through the gas inlet pipe and the second microporous aerator into the coupling bioreactor in the form of microbubbles; allowing the wastewater, the malodorous gas, and the air to flow up synchronously so that the suspended carrier moves randomly by the drive of water flow and air flow to facilitate the contact of organic pollutants in the malodorous gas and the wastewater and the oxygen in the air with the biofilm growing on the suspended carrier to degrade the organic pollutants by microbes; and
4) guiding the wastewater after treatment out of the coupling bioreactor through the annular overflow weir and the water outlet pipe; and discharging a gas released from the wastewater via the gas outlet pipe.

8. The method of claim 7 , wherein a density of the suspended carrier before a biofilm formation is between 0.97 and 0.98 g/cm 3 ; and a density of the suspended carrier after the biofilm formation is 1 g/cm 3 .

9. The method of claim 7 , wherein the first microporous aerator and the second microporous aerator are disc type membrane microporous aerators; and the air and the malodorous gas are introduced into the coupling bioreactor in the form of microbubbles having a diameter of about 100 μm.

10. The method of claim 8 , wherein the first microporous aerator and the second microporous aerator are disc type membrane microporous aerators; and the air and the malodorous gas are introduced into the coupling bioreactor in the form of microbubbles having a diameter of about 100 μm.

Assignees

• Nanjing University Of Technology

Inventors

• Ren Hongqiang
• Xu Ke
• Ding Lili
• Geng Jinju

Classifications

• B01D53/52

  Hydrogen sulfide · CPC title

• B01D53/58

  Ammonia · CPC title

• B01D53/84

  Biological processes · CPC title

• B01D2251/11

  Air · CPC title

• B01D2257/90

  Odorous compounds not provided for in groups B01D2257/00 - B01D2257/708 · CPC title