Method for Reducing Release of Resistance Genes during Sludge Anaerobic Treatment

Patent metadata

Field	Value
Publication number	US-2016229727-A1
Application number	US-201514930129-A
Country	US
Kind code	A1
Filing date	Nov 2, 2015
Priority date	Feb 3, 2015
Publication date	Aug 11, 2016
Grant date	—

Abstract

A method for reducing release of resistance genes during sludge anaerobic treatment includes controlling concentration of to-be-treated sludge in a concentration tank to be 12-20 g/L by sedimentation under gravity. The concentrated sludge is transferred to a supersonic pre-treatment device to proceed with supersonic pre-treatment. The supersonic pre-treatment is conducted for 5-30 minutes at a power of 0.1-0.5 kW and a frequency of 10-40 kHz. The pre-treated sludge is then transferred to an anaerobic treatment device for anaerobic treatment. The anaerobic treatment is conducted for 4-12 days at a temperature of 20-37° C. The release amount of resistance genes in the residual sludge and the supernatant liquid in the anaerobic treatment device is detected. A feedback dosage of an alkali liquid is fed into the anaerobic treatment device according to the release amount of the resistance genes, controlling a pH value to be 9.0-11.0 during the anaerobic treatment.

First claim

1 . A method for reducing release of resistance genes during sludge anaerobic treatment, with the method carried out by using a system including a concentration tank ( 1 ), a supersonic pre-treatment device ( 2 ), an anaerobic treatment device ( 3 ), a real-time fluorescent quantitative polymerase chain reaction (PCR) instrument ( 4 ), a computer ( 5 ), an alkali storage tank ( 6 ), an electric valve ( 7 ), and a pH detector ( 8 ), with the concentration tank ( 1 ) including a bottom connected by a conduit and a valve to a sludge inlet in an upper portion of the supersonic pre-treatment device ( 2 ), with the supersonic pre-treatment device ( 2 ) including a sludge outlet connected to the anaerobic treatment device ( 3 ), with the anaerobic treatment device ( 3 ) including a lower portion having an outlet for residual sludge, with the anaerobic treatment device ( 3 ) further including an upper portion having an outlet for a supernatant liquid, with the residual sludge and the supernatant liquid being detected while passing through the real-time fluorescent quantitative PCR instrument ( 4 ), with the alkali storage tank ( 6 ) including a bottom connected by a conduit and the electric valve ( 7 ) to an inlet in a top of the anaerobic treatment device ( 3 ), with the pH detector ( 8 ) mounted on the upper portion of the anaerobic treatment device ( 3 ), with the computer ( 5 ) connected to the real-time fluorescent quantitative PCR instrument ( 4 ), the electric valve ( 7 ), and the pH detector ( 8 ), with the method comprising:
(1) controlling concentration of to-be-treated sludge in the concentration tank ( 1 ) to be 12-20 g/L by sedimentation under gravity; (2) transferring the concentrated sludge into the supersonic pre-treatment device ( 2 ) to proceed with supersonic pre-treatment, with the supersonic pre-treatment conducted for 5-30 minutes at a power of 0.1-0.5 kW and a frequency of 10-40 kHz; (3) transferring the pre-treated sludge into the anaerobic treatment device ( 3 ) for anaerobic treatment, with the anaerobic treatment conducted for 4-12 days at a temperature of 20-37° C.; (4) detecting a release amount of resistance genes in residual sludge and the supernatant liquid in the anaerobic treatment device ( 3 ) with the real-time fluorescent quantitative polymerase chain reaction (PCR) instrument ( 4 ); and (5) controlling a feedback dosage of an alkali liquid according to the release amount of the resistance genes and feeding the feedback dosage of the alkali liquid into the anaerobic treatment device ( 3 ) to control a pH value to be 9.0-11.0 during the anaerobic treatment.

2 . The method for reducing release of resistance genes during sludge anaerobic treatment as claimed in claim 1 , wherein the to-be-treated sludge in step (1) is primary sludge or the excess sludge or a mixture of the primary sludge and the excess sludge at an arbitrary ratio.

3 . The method for reducing release of resistance genes during sludge anaerobic treatment as claimed in claim 1 , wherein the resistance genes to be detected in step (4) include sulfonamide resistance genes sul I and sul II and tetracycline resistance genes tet O and tet Q.

4 . The method for reducing release of resistance genes during sludge anaerobic treatment as claimed in claim 1 , wherein:
the concentration of the to-be-treated sludge in the concentration tank ( 1 ) is controlled to be 15 g/L in step (1); the supersonic pre-treatment in step (2) is conducted for 15 minutes at a power of 0.3 kW and a frequency of 30 kHz; the anaerobic treatment in step (3) is conducted for 8 days at a temperature of 35° C.; and the pH value is controlled to be 10.0.

5 . A method for reducing release of resistance genes during sludge anaerobic treatment, comprising:
(1) controlling concentration of to-be-treated sludge in a concentration tank to be 12-20 g/L by sedimentation under gravity; (2) transferring the concentrated sludge into a supersonic pre-treatment device to proceed with supersonic pre-treatment, with the supersonic pre-treatment conducted for 5-30 minutes at a power of 0.1-0.5 kW and a frequency of 10-40 kHz; (3) transferring the pre-treated sludge into an anaerobic treatment device for anaerobic treatment, with the anaerobic treatment conducted for 4-12 days at a temperature of 20-37° C.; (4) detecting a release amount of resistance genes in residual sludge and the supernatant liquid in the anaerobic treatment device; and (5) feeding a feedback dosage of an alkali liquid into the anaerobic treatment device according to the release amount of the resistance genes, controlling a pH value to be 9.0-11.0 during the anaerobic treatment.

6 . The method for reducing release of resistance genes during sludge anaerobic treatment as claimed in claim 5 , wherein the to-be-treated sludge in the concentration tank is primary sludge or the excess sludge or a mixture of the primary sludge and the excess sludge at an arbitrary ratio.

7 . The method for reducing release of resistance genes during sludge anaerobic treatment as claimed in claim 5 , wherein the release amount of resistance genes in residual sludge and the supernatant liquid in the anaerobic treatment device is detected by using a real-time fluorescent quantitative polymerase chain reaction (PCR) instrument, and wherein the resistance genes to be detected include sulfonamide resistance genes sul I and sul II and tetracycline resistance genes tet O and tet Q.

8 . The method for reducing release of resistance genes during sludge anaerobic treatment as claimed in claim 5 , wherein:
the concentration of the to-be-treated sludge in the concentration tank is controlled to be 15 g/L; the supersonic pre-treatment is conducted for 15 minutes at a power of 0.3 kW and a frequency of 30 kHz; the anaerobic treatment is conducted for 8 days at a temperature of 35° C.; and the pH value is controlled to be 10.0.

Assignees

• Univ Tongji

Inventors

• Chen Yinguang
• Zheng Xiong
• Huang Haining
• Su Yinglong
• Li Mu
• Wu Lijuan

Classifications

• C02F2101/30

  Organic compounds · CPC title

• C02F1/36

  ultrasonic vibrations · CPC title

• C02F2209/36

  Biological material, e.g. enzymes or ATP · CPC title

• C02F2209/06

  pH · CPC title

• C02F2303/06

  Sludge reduction, e.g. by lysis · CPC title