Method for treating arsenic-containing flue gas

Patent metadata

Field	Value
Publication number	US-12097461-B2
Application number	US-202117546786-A
Country	US
Kind code	B2
Filing date	Dec 9, 2021
Priority date	Sep 13, 2021
Publication date	Sep 24, 2024
Grant date	Sep 24, 2024

Abstract

A method for treating arsenic-containing flue gas is disclosed. In the method, the arsenic-containing flue gas is subjected to a dry pre-dedusting treatment, and the dedusted flue gas is pre-cooled and then introduced into a vortex quenching system. The arsenic-containing flue gas is divided into high-temperature flue gas and low-temperature flue gas through the vortex quenching system. The outlet temperature of the low-temperature flue gas is dropped below the desublimation temperature of gaseous arsenic trioxide. The low-temperature flue gas is subjected to a gas-solid separation to obtain solid arsenic trioxide and treated flue gas.

First claim

What is claimed is:

1. A method for treating arsenic-containing flue gas, comprising:
subjecting the arsenic-containing flue gas to a dry pre-dedusting treatment, to obtain dedusted flue gas;
pre-cooling the dedusted flue gas and introducing the pre-cooled flue gas into a vortex quenching system to obtain high-temperature flue gas and low-temperature flue gas; and
subjecting the low-temperature flue gas to a gas-solid separation to obtain treated flue gas and arsenic trioxide,
wherein the pre-cooled flue gas has a residence time of 1 to 3 seconds in the vortex quenching system, and the low-temperature flue gas has a temperature of ≤150° C.

2. The method as claimed in claim 1 , wherein the dry pre-dedusting treatment is performed in a high temperature-resistant pre-dedusting system.

3. The method as claimed in claim 1 , wherein the gas-solid separation is performed in a bag-type dust collector.

4. The method as claimed in claim 1 , wherein the treated flue gas has an arsenic element content of 0.15 to 0.35 mg/m 3 , and a dust content of 16 to 20 mg/m 3 .

5. The method as claimed in claim 1 , wherein the vortex quenching system comprises a gas inlet pipe, a gas inlet spray nozzle, a vortex chamber, a low-temperature gas outlet, a high-temperature gas buffer chamber, a gas outlet adjustment valve, and a high-temperature gas outlet, wherein the gas inlet spray nozzle is arranged at the top of the vortex chamber; the gas inlet pipe is connected to the gas inlet spray nozzle; the low-temperature gas outlet is arranged on one side of the vortex chamber; the high-temperature gas buffer chamber is arranged on the other side of the vortex chamber; the high-temperature gas outlet is arranged in one end, far away from the vortex chamber, of the high-temperature gas buffer chamber; and the high-temperature gas outlet is provided with the gas outlet adjustment valve.

6. A method for treating arsenic-containing flue gas, comprising:
subjecting the arsenic-containing flue gas to a dry pre-dedusting treatment, to obtain dedusted flue gas;
pre-cooling the dedusted flue gas and introducing the pre-cooled flue gas into a vortex quenching system to obtain high-temperature flue gas and low-temperature flue gas; and
subjecting the low-temperature flue gas to a gas-solid separation to obtain treated flue gas and arsenic trioxide,
wherein pre-cooling the dedusted flue gas comprises introducing the dedusted flue gas into a heat energy utilization system and cooling.

7. The method as claimed in claim 6 , wherein the high-temperature flue gas is recycled to the heat energy utilization system.

8. A method for treating arsenic-containing flue gas, comprising:
subjecting the arsenic-containing flue gas to a dry pre-dedusting treatment, to obtain dedusted flue gas;
pre-cooling the dedusted flue gas and introducing the pre-cooled flue gas into a vortex quenching system to obtain high-temperature flue gas and low-temperature flue gas; and
subjecting the low-temperature flue gas to a gas-solid separation to obtain treated flue gas and arsenic trioxide,
wherein the vortex quenching system comprises a gas inlet pipe, a gas inlet spray nozzle, a vortex chamber, a low-temperature gas outlet, a high-temperature gas buffer chamber, a gas outlet adjustment valve, and a high-temperature gas outlet, wherein the gas inlet spray nozzle is arranged at the top of the vortex chamber; the gas inlet pipe is connected to the gas inlet spray nozzle; the low-temperature gas outlet is arranged on one side of the vortex chamber; the high-temperature gas buffer chamber is arranged on the other side of the vortex chamber; the high-temperature gas outlet is arranged in one end, far away from the vortex chamber, of the high-temperature gas buffer chamber; and the high-temperature gas outlet is provided with the gas outlet adjustment valve.

9. The method as claimed in claim 8 , wherein the gas inlet spray nozzle is arranged in the tangential direction of the vortex chamber.

10. The method as claimed in claim 8 , wherein the relationship between the length L of the high-temperature gas buffer chamber and the diameter H of the vortex chamber is represented by L/H=20-40.

Assignees

• Bgrimm Tech Group
• Univ Kunming Science & Technology

Inventors

• Chen Guoqiang
• Tian Senlin
• Ning Ping
• Yang Xiaosong
• Shao Linan
• Zhao Zhilong

Classifications

• F27D17/10

  Arrangements for using waste heat · CPC title

• F27D17/20 Primary

  Arrangements for treatment or cleaning of waste gases · CPC title

• B01D46/02

  Particle separators, e.g. dust precipitators, having hollow filters made of flexible material · CPC title

• B01D5/0072

  with filtration · CPC title

• B01D5/0021

  Vortex · CPC title