Low pressure drop static mixing system

• US 10,350,545 B2
• Filed: 11/24/2015
• Issued: 07/16/2019
• Est. Priority Date: 11/25/2014
• Status: Active Grant

• Current Assignee: ARQ Solutions Incorporated
• Original Assignee: ADA-ES, Inc. (Advanced Emissions Solutions, Inc.)
• Inventors: Hanson, Ronald
• Primary Examiner(s): Nassiri-Motlagh, Anita
• Application Number:
  US14/951,211
• Publication Number:
  US 20160144316A1
• Time in Patent Office: 1,330 Days
• Field of Search: None
• CPC Class Codes: B01D 2251/108 Halogens or halogen compounds
• CPC Class Codes: B01D 2251/30 Alkali metal compounds
• CPC Class Codes: B01D 2251/40 Alkaline earth metal or magnesium compounds
• CPC Class Codes: B01D 2251/404 of calcium
• CPC Class Codes: B01D 2251/606 Carbonates
• CPC Class Codes: B01D 2257/2045 Hydrochloric acid
• CPC Class Codes: B01D 2257/2047 Hydrofluoric acid
• CPC Class Codes: B01D 2257/302 Sulfur oxides
• CPC Class Codes: B01D 2257/304 Hydrogen sulfide
• CPC Class Codes: B01D 2257/404 Nitrogen oxides other than dinitrogen oxide
• CPC Class Codes: B01D 2257/602 Mercury or mercury compounds
• CPC Class Codes: B01D 2258/0233 from cement factories
• CPC Class Codes: B01D 2258/025 from metallurgy plants
• CPC Class Codes: B01D 2258/0283 Flue gases
• CPC Class Codes: B01D 2258/0291 from waste incineration plants
• CPC Class Codes: B01D 2259/124 Liquid reactants
• CPC Class Codes: B01D 2259/126 Semi-solid reactants, e.g. slurries
• CPC Class Codes: B01D 2259/128 Solid reactants
• CPC Class Codes: B01D 53/504 characterised by a specific device
• CPC Class Codes: B01D 53/508 by treating the gases with solids
• CPC Class Codes: B01D 53/52 : Hydrogen sulfide
• CPC Class Codes: B01D 53/56 : Nitrogen oxides B01D53/60 takes precedence
• CPC Class Codes: B01D 53/64 : Heavy metals or compounds thereof, e.g. mercury
• CPC Class Codes: B01D 53/68 : Halogens or halogen compounds
• CPC Class Codes: B01D 53/79 : Injecting reactants
• CPC Class Codes: B01D 53/83 : with moving reactants
• CPC Class Codes: F23J 15/003 : for supplying chemicals to fumes, e.g. using injection devices
• CPC Class Codes: F23J 15/006 : Layout of treatment plant
• CPC Class Codes: F23J 2215/10 : Nitrogen; Compounds thereof
• CPC Class Codes: F23J 2215/20 : Sulfur; Compounds thereof
• CPC Class Codes: F23J 2215/30 : Halogen; Compounds thereof
• CPC Class Codes: F23J 2217/101 : Baghouse type
• CPC Class Codes: F23J 2217/102 : electrostatic
• CPC Class Codes: F23J 2219/30 : Sorption devices using carbon, e.g. coke

Abstract

A contaminated gas stream can be passed through an in-line mixing device, positioned in a duct containing the contaminated gas stream, to form a turbulent contaminated gas stream. One or more of the following is true: (a) a width of the in-line mixing device is no more than about 75% of a width of the duct at the position of the in-line mixing device; (b) a height of the in-line mixing device is no more than about 75% of a height of the duct at the position of the in-line mixing device; and (c) a cross-sectional area of the mixing device normal to a direction of gas flow is no more than about 75% of a cross-sectional area of the duct at the position of the in-line mixing device. An additive can be introduced into the contaminated gas stream to cause the removal of the contaminant by a particulate control device.

Claims

1. A contaminated gas treatment system, comprising:

a thermal unit to produce a contaminated gas stream comprising a contaminant;

an air heater positioned in a flow path of the contaminated gas stream downstream from the thermal unit to transfer thermal energy from the contaminated gas stream to air prior to introduction of the air into the thermal unit;

an in-line mixing device positioned in the flow path of the contaminated gas stream downstream from the thermal unit to induce turbulent flow in the contaminated gas stream, the in-line mixing device being positioned in a duct defining the flow path of the contaminated gas stream, wherein the in-line mixing device comprises a static mixing device, wherein the static in-line mixing device comprises one or more stationary mixing elements fixed in a housing of the mixing device, wherein the static in-line mixing device rotates relative to a flow direction of the contaminated gas stream, wherein, when the static in-line mixing device is in a first position relative to the flow direction, the contaminated gas stream has a first pressure drop over the in-line mixing device, wherein, when the static in-line mixing device is in a different second position relative to the flow direction, the contaminated gas stream has a second pressure drop over the in-line mixing device, wherein the first and second pressure drops are different, and wherein at least one of the following is true;

(a) a width of the in-line mixing device is no more than about 75% of a width of the duct at the position of the in-line mixing device;

(b) a height of the in-line mixing device is no more than about 75% of a height of the duct at the position of the in-line mixing device; and

(c) a cross-sectional area of the in-line mixing device normal to a direction of gas flow is no more than about 75% of a cross-sectional area of the duct at the position of the in-line mixing device; and

an additive injection system positioned in the flow path of the contaminated gas stream upstream or downstream of the in-line mixing device to introduce an additive into the contaminated gas stream, the additive controlling a contaminate level in a treated gas stream prior to discharge of the treated gas stream into the environment, wherein the in-line mixing device and additive injection system cause the additive-containing gas stream to comprise a substantially homogeneous distribution of the additive in the additive-containing gas stream; and

a particulate control device positioned in the flow path of the contaminated gas stream downstream of the in-line mixing device to remove particulates from the additive-containing gas stream and form the treated gas stream;

a computer;

a rotation sensor to determine a degree of angular rotation of the in-line mixing device and/or a mixing element of the mixing device relative to the flow direction;

one or more gas stream sensors to determine one or more sensed parameters comprising one or more of the pressure drop over the in-line mixing device, an additive consumption level, and a contaminant concentration in the gas stream prior to or after additive injection;

a rotation system to rotate the in-line mixing device and/or mixing element; and

a computer operated control system in communication with the rotation sensor, one or more gas stream sensors, and rotation system and comprising a set of mapping data structures mapping one or more sensed parameters against a degree of angular rotation of the mixing device and/or mixing element and instructions that, when executed by the computer, cause the computer operated control system to;

receive a degree of current angular rotation of the in-line mixing device and/or mixing element and the one or more sensed parameters;

based on the received degree of current angular rotation of the in-line mixing device and/or mixing element and the one or more sensed parameters, determine, from the mapping data structures, a new degree of angular rotation of the in-line mixing device and/or mixing element; and

cause the in-line mixing device and/or mixing element to rotate from the current angular rotation to the new angular rotation.

2. The system of claim 1, wherein the thermal unit combusts the contaminated feed material to produce the contaminated gas stream and wherein (a) is true.

3. The system of claim 2, wherein the width of the in-line mixing device is no more than about 50% of the duct width at the in-line mixing device position.

4. The system of claim 1, wherein the thermal unit combusts the contaminated feed material to produce the contaminated gas stream and wherein (b) is true.

5. The system of claim 4, wherein the height of the in-line mixing device is no more than about 50% of the duct height at the in-line mixing device position.

6. The system of claim 1, wherein the thermal unit combusts the contaminated feed material to produce the contaminated gas stream and wherein (c) is true.

7. The system of claim 6, wherein the in-line static mixing device has a cross-sectional area of the in-line mixing device normal to a direction of gas flow that is no more than about 50% of a cross-sectional area of the duct at the position of the in-line mixing device.

8. The system of claim 7, wherein the in-line mixing device comprises a plurality of mixing elements to induce turbulence of the contaminated gas stream, wherein the in-line static mixing device has a cross-sectional area of the in-line mixing device normal to a direction of gas flow that is no more than about 25% of a cross-sectional area of the duct at the position of the in-line mixing device and wherein a remainder of the cross-sectional area of the duct at the position of the in-line mixing device is free of any mixing elements.

9. The system of claim 1, wherein a distance from an output of the in-line mixing device to an input of the particulate control device is at least about one times but no more than about ten times a hydraulic diameter of the duct, and wherein the additive is injected upstream and/or downstream of the in-line mixing device.

10. The system of claim 1, wherein the additive injection system is positioned upstream of the in-line mixing device, wherein a distance from an input of the in-line mixing device to an output of the additive injection system is at least about 0.1 times but no more than about one times a hydraulic diameter of the duct, wherein the additive is a liquid additive, and wherein the additive is injected downstream of, and in the turbulent contaminated gas stream flow produced by, the in-line mixing device.

21. The system of claim 1, wherein the thermal unit causes generation of electrical power, wherein the one or more gas stream sensors determines the pressure drop over the in-line mixing device, wherein the computer operated control system is in communication with a load profile meter that determines a current demand for electrical power, and wherein the computer operated control system, based on a current electrical power demand, selects a pressure drop over the mixing device, and uses the pressure drop to select the new degree of angular rotation.

11. A contaminated gas treatment system, comprising:

an in-line mixing device positioned in a flow path of a contaminated gas stream, comprising a contaminant, downstream from a thermal unit to induce turbulent flow in the contaminated gas stream, the in-line mixing device being positioned in a duct defining the flow path of the contaminated gas stream, wherein the in-line mixing device comprises a static mixing device, wherein the static in-line mixing device comprises one or more stationary mixing elements fixed in a housing of the in-line mixing device, wherein the static in-line mixing device rotates relative to a flow direction of the contaminated gas stream, wherein, when the in-line mixing device is in a first orientation relative to the flow direction, the contaminated gas stream has a first pressure drop over the in-line mixing device, wherein, when the in-line mixing device is in a different second orientation relative to the flow direction, the contaminated gas stream has a second pressure drop over the in-line mixing device, wherein the first and second pressure drops are different, and wherein at least one of the following is true;

(a) a width of the in-line mixing device is no more than about 75% of a width of the duct at the position of the in-line mixing device;

(b) a height of the in-line mixing device is no more than about 75% of a height of the duct at the position of the in-line mixing device; and

(c) a cross-sectional area of the in-line mixing device normal to a direction of gas flow is no more than about 75% of a cross-sectional area of the duct at the position of the in-line mixing device; and

an additive injection system positioned in the flow path of the contaminated gas stream upstream or downstream of the in-line mixing device to introduce an additive into the contaminated gas stream, the additive controlling a contaminate level in a treated gas stream prior to discharge of the treated gas stream into the environment, wherein the in-line mixing device and additive injection system cause the additive-containing gas stream to comprise a substantially homogeneous distribution of the additive in the additive-containing gas stream; and

a particulate control device positioned in the flow path of the contaminated gas stream downstream of the in-line mixing device to remove particulates from the additive-containing gas stream and form the treated gas stream;

a computer;

a rotation sensor to determine a degree of angular rotation of the mixing device and/or a mixing element of the in-line mixing device relative to the flow direction;

one or more gas stream sensors to determine one or more sensed parameters comprising one or more of the pressure drop, an additive consumption level, and a contaminant concentration in the gas stream prior to or after sorbent injection;

a rotation system to rotate the in-line mixing device and/or mixing element; and

a computer operated control system in communication with the rotation sensor, one or more gas stream sensors, and rotation system and comprising a set of mapping data structures mapping one or more sensed parameters against a degree of angular rotation of the mixing device and/or mixing element and instructions that, when executed by the computer, cause the computer operated control system to;

receive a degree of current angular rotation of the mixing device and/or mixing element and the one or more sensed parameters;

based on the received degree of current angular rotation of the mixing device and/or mixing element and the one or more sensed parameters, determine, from the mapping data structures, a new degree of angular rotation of the in-line mixing device and/or mixing element; and

cause the in-line mixing device and/or mixing element to rotate from the current angular rotation to the new angular rotation.

12. The system of claim 11, wherein a thermal unit combusts a contaminated feed material to produce the contaminated gas stream and wherein (a) is true.

13. The system of claim 12, wherein the contaminated gas stream has a gas velocity ranging from about 5 to about 50 m/s, and wherein the width of the in-line mixing device is no more than about 50% of the duct width at the in-line mixing device position.

14. The system of claim 11, wherein a thermal unit combusts a contaminated feed material to produce the contaminated gas stream and wherein (b) is true.

15. The system of claim 14, wherein the height of the in-line mixing device is no more than about 50% of the duct height at the in-line mixing device position.

16. The system of claim 11, wherein a thermal unit combusts a contaminated feed material to produce the contaminated gas stream and wherein (c) is true.

17. The system of claim 16, wherein the in-line static mixing device has a cross-sectional area of the in-line mixing device normal to a direction of gas flow that is no more than about 50% of a cross-sectional area of the duct at the position of the in-line mixing device, and wherein the in-line mixing device comprises a plurality of mixing elements to induce turbulence of the contaminated gas stream.

18. The system of claim 17, wherein the plurality of mixing elements are stationary, fixed, and/or static fan-type blades, wherein the in-line static mixing device has a cross-sectional area of the in-line mixing device normal to a direction of gas flow that is no more than about 25% of a cross-sectional area of the duct at the position of the in-line mixing device and wherein a remainder of the cross-sectional area of the duct at the position of the in-line mixing device is free of any mixing elements.

19. The system of claim 11, wherein the additive is injected upstream and/or downstream of the in-line mixing device.

20. The system of claim 11, wherein the additive injection system is positioned downstream of the in-line mixing device, wherein the additive is a liquid additive, and wherein the additive is injected downstream of, and in the turbulent contaminated gas stream flow produced by, the in-line mixing device.

22. The system of claim 11, wherein the thermal unit causes generation of electrical power, wherein the one or more gas stream sensors determines the pressure drop, wherein the computer operated control system is in communication with a load profile meter that determines a current demand for electrical power, and wherein the computer operated control system, based on a current electrical power demand, selects a pressure drop over the mixing device, and uses the pressure drop to select the new degree of angular rotation.

23. A contaminated gas treatment system, comprising:

an in-line mixing device positioned in a flow path of a contaminated gas stream, comprising a contaminant, downstream from a thermal unit to induce turbulent flow in the contaminated gas stream, the in-line mixing device being positioned in a duct defining the flow path of the contaminated gas stream, wherein the in-line mixing device is positioned in only a first portion of a cross-sectional area of the duct normal to a direction of gas flow and a second portion of the cross-sectional area of the duct is free of the in-line mixing device, wherein the in-line mixing device comprises a static mixing device, wherein the static in-line mixing device comprises one or more stationary mixing elements fixed in a housing of the in-line mixing device, wherein the static in-line mixing device rotates relative to a flow direction of the contaminated gas stream, wherein, when the in-line mixing device is in a first position relative to the flow direction, the contaminated gas stream has a first pressure drop over the in-line mixing device, wherein, when the in-line mixing device is in a different second position relative to the flow direction, the contaminated gas stream has a second pressure drop over the in-line mixing device, and wherein the first and second pressure drops are different, and wherein the first portion of the cross-sectional area is no more than about 75% of a cross-sectional area of the duct at the position of the in-line mixing device;

an additive injection system positioned in the flow path of the contaminated gas stream upstream or downstream of the in-line mixing device to introduce an additive into the contaminated gas stream, the additive controlling a contaminate level in a treated gas stream prior to discharge of the treated gas stream into the environment, wherein the in-line mixing device and additive injection system cause the additive-containing gas stream to comprise a substantially homogeneous distribution of the additive in the additive-containing gas stream;

a particulate control device positioned in the flow path of the contaminated gas stream downstream of the in-line mixing device to remove particulates from the additive-containing gas stream and form the treated gas stream;

a computer;

a rotation sensor to determine a degree of angular rotation of the mixing device and/or a mixing element of the mixing device relative to the flow direction;

one or more gas stream sensors to determine one or more sensed parameters comprising one or more of the pressure drop over the in-line mixing device, an additive consumption level, and a contaminant concentration in the gas stream prior to or after additive injection;

a rotation system to rotate the mixing device and/or mixing element; and

a computer operated control system in communication with the rotation sensor, one or more gas stream sensors, and rotation system and comprising a set of mapping data structures mapping one or more sensed parameters against a degree of angular rotation of the mixing device and/or mixing element and instructions that, when executed by the computer, cause the computer operated control system to;

receive a degree of current angular rotation of the in-line mixing device and/or mixing element and the one or more sensed parameters;

based on the received degree of current angular rotation of the in-line mixing device and/or mixing element and the one or more sensed parameters, determine, from the mapping data structures, a new degree of angular rotation of the in-line mixing device and/or mixing element; and

cause the in-line mixing device and/or mixing element to rotate from the current angular rotation to the new angular rotation.

24. The system of claim 23, wherein the thermal unit causes generation of electrical power, wherein the one or more gas stream sensors determines the pressure drop over the in-line mixing device, wherein the computer operated control system is in communication with a load profile meter that determines a current demand for electrical power, and wherein the computer operated control system, based on a current electrical power demand, selects a pressure drop over the in-line mixing device, and uses the pressure drop to select the new degree of angular rotation.