Air treatment process for dilute phase injection of dry alkaline materials
View Patent ↗The present disclosure is directed to the introduction of an additive to a contaminated gas stream. An additive introduction system uses a compressor and carbon dioxide separator to provide a treated carrier gas for introduction of an alkaline additive to a contaminated gas stream.
1. A method, comprising:
introducing, by an array of lances, an additive-containing fluid, comprising an additive material and carrier gas, into a contaminated gas stream;
in response to a sensed stimulus associated with an additive deposited in a first lance, terminating flow of the additive material through the first lance of the lance array but not through at least one other lance of the lance array;
while the additive material is not flowing through the first lance, flowing, through the first lance, at least one of a purge gas and a chemical cleaner, to remove at least part of the additive deposited in the first lance; and
thereafter commencing flow of the additive material through the first lance.
2. The method of claim 1 , wherein the stimulus is at least one of passage of a selected time interval and a measured flow resistance of the additive-containing fluid across a carrier gas/additive mixing system and/or carrier gas/additive delivery system, the carrier gas/additive delivery system comprising the lance array, wherein the at least one of a purge gas and a chemical cleaner is the purge gas, wherein the purge gas has a different characteristic from the carrier gas, the characteristic being one or more of a pressure, composition, temperature, and flow velocity, and further comprising:
after termination of flow the additive material through the first lance, continuing to pass the carrier gas through the first lance to remove at least some additive from the first lance; and
before the purge gas is flowed through the first lance, fluidly isolating the first lance from the carrier gas, whereby flow of the carrier gas through the first lance is terminated while the purge gas flows through the first lance.
3. The method of claim 2 , wherein the purge gas is a compressed gas, wherein flow is additive flow is terminated by shutting off a rotary valve supplying additive to the carrier gas, and wherein the first lance is fluidly isolated by closing a valve positioned between the first lance and the at least one other lance.
4. The method of claim 2 , wherein, while the flow of the additive material is terminated, the first lance is placed in fluid communication with a first sensor, wherein the first sensor measures and provides to a controller a magnitude and/or direction of carrier gas flow or the pressure differential of a duct draw, wherein, based on the first sensor measurement, the controller determines whether additive-containing fluid flow through the first lance is acceptable, wherein, when the additive-containing fluid flow through the first lance is not acceptable, the purge gas flowing step is performed, and wherein, when the additive-containing fluid flow through the first lance is acceptable, the purge gas flowing step is not performed.
5. The method of claim 4 , wherein, after the purge gas flowing step, the first sensor measures and provides to a controller a magnitude and/or direction of carrier gas flow or the pressure differential of a duct draw through the first lance, wherein, based on the first sensor measurement, the controller determines whether additive-containing fluid flow through the first lance is now acceptable after purge gas flow, wherein, when the additive-containing fluid flow through the first lance is not yet acceptable, the purge gas flowing step is again performed, and wherein, when the additive-containing fluid flow through the first lance is now acceptable, the purge gas flowing step is not performed again.
6. The method of claim 1 , wherein the at least one of a purge gas and a chemical cleaner is the purge gas, wherein the purge gas has a different characteristic from the carrier gas, the characteristic being one or more of a pressure, composition, temperature, and flow velocity, and further comprising:
before the terminating and thereafter commencing steps, quantifying, parametrically assessing, and/or measuring a duct draw;
quantifying, parametrically assessing and/or measuring an amount of the purge gas flowed through the first lance; and
determining, based on the results of the quantifying, parametrically assessing, and/or measuring steps, a propensity of the first lance to plug or have reduced flow, the stimulus being dependent on the propensity of the first lance to plug or have reduced flow.
7. The method of claim 1 , wherein the stimulus is at least one of passage of a selected time interval and a measured flow resistance of the additive-containing fluid across a carrier gas/additive mixing system and/or carrier gas/additive delivery system, the carrier gas/additive delivery system comprising the lance array, wherein the at least one of a purge gas and a chemical cleaner is the chemical cleaner, and further comprising:
after termination of flow the additive material through the first lance, continuing to pass the carrier gas with the chemical cleaner through the first lance to remove at least some additive from the first lance.
8. The method of claim 7 , wherein the chemical cleaner is a mineral acid or acid gas.
9. A tangible and non transitory computer readable medium comprising microprocessor executable instructions that, when executed, cause performance of the terminating, flowing, and thereafter commencing steps of claim 1 .
10. A method, comprising:
introducing, by a plurality of lances, an additive-containing fluid, comprising an additive material and carrier gas, into a contaminated gas stream;
in response to a sensed stimulus associated with an additive deposited in a first lance, fluidly isolating the first lance from at least one other lance of the plurality of lances;
in response to the sensed stimulus, flowing, through the first lance but not through the at least one other lance, at least one of a purge gas and a chemical cleaner to remove at least part of the additive deposited in the first lance; and
while the at least one of a purge gas and a chemical cleaner flows through the first lance, continuing to flow the additive-containing fluid through the at least one other lance.
11. The method of claim 10 , further comprising:
while the first lance is fluidly isolated, suspending flow of the additive material through the first lance of the lance array but not through at least one other lance of the lance array; and
when the at least part of the additive deposited in the first lance is removed, recommencing flow the additive material fluid through the first lance.
12. The method of claim 11 , wherein the stimulus is at least one of passage of a selected time interval and a measured flow resistance of the additive-containing fluid across a carrier gas/additive mixing system and/or carrier gas/additive delivery system, the carrier gas/additive delivery system comprising the plurality of lances, wherein the at least one of a purge gas and a chemical cleaner is the purge gas, wherein the purge gas has a different characteristic from the carrier gas, the characteristic being one or more of a pressure, composition, temperature, and flow velocity, and further comprising:
after termination of flow the additive material through the first lance, continuing to pass the carrier gas through the first lance to remove at least some additive from the first lance; and
before the purge gas is flowed through the first lance, fluidly isolating the first lance from the carrier gas, whereby flow of the carrier gas through the first lance is terminated while the purge gas flows through the first lance.
13. The method of claim 12 , wherein the purge gas is a compressed gas, wherein flow is additive flow is terminated by shutting off a rotary valve supplying additive to the carrier gas, and wherein the first lance is fluidly isolated by closing a valve positioned between the first lance and the at least one other lance.
14. The method of claim 12 , wherein, while the flow of the additive material is terminated, the first lance is placed in fluid communication with a first sensor, wherein the first sensor measures and provides to a controller a magnitude and/or direction of carrier gas flow or the pressure differential of a duct draw, wherein, based on the first sensor measurement, the controller determines whether additive-containing fluid flow through the first lance is acceptable, wherein, when the additive-containing fluid flow through the first lance is not acceptable, the purge gas flowing step is performed, and wherein, when the additive-containing fluid flow through the first lance is acceptable, the purge gas flowing step is not performed.
15. The method of claim 14 , wherein, after the purge gas flowing step, the first sensor measures and provides to a controller a magnitude and/or direction of carrier gas flow or the pressure differential of a duct draw through the first lance, wherein, based on the first sensor measurement, the controller determines whether additive-containing fluid flow through the first lance is now acceptable after purge gas flow, wherein, when the additive-containing fluid flow through the first lance is not yet acceptable, the purge gas flowing step is again performed, and wherein, when the additive-containing fluid flow through the first lance is now acceptable, the purge gas flowing step is not performed again.
16. The method of claim 11 , wherein the at least one of a purge gas and a chemical cleaner is the purge gas, wherein the purge gas has a different characteristic from the carrier gas, the characteristic being one or more of a pressure, composition, temperature, and flow velocity, and further comprising:
before the terminating and thereafter commencing steps, quantifying, parametrically assessing, and/or measuring a duct draw;
quantifying, parametrically assessing and/or measuring an amount of the purge gas flowed through the first lance; and
determining, based on the results of the quantifying, parametrically assessing, and/or measuring steps, a propensity of the first lance to plug or have reduced flow, the stimulus being dependent on the propensity of the first lance to plug or have reduced flow.
17. The method of claim 11 , wherein the stimulus is at least one of passage of a selected time interval and a measured flow resistance of the additive-containing fluid across a carrier gas/additive mixing system and/or carrier gas/additive delivery system, the carrier gas/additive delivery system comprising the lance array, wherein the at least one of a purge gas and a chemical cleaner is the chemical cleaner, and further comprising:
after termination of flow the additive material through the first lance, continuing to pass the carrier gas with the chemical cleaner through the first lance to remove at least some additive from the first lance.
18. The method of claim 17 , wherein the chemical cleaner is a mineral acid or acid gas.
19. A tangible and non transitory computer readable medium comprising microprocessor executable instructions that, when executed, cause performance of the fluidly isolating and flowing steps of claim 10 .
20. A system, comprising:
a mixing system to mix an additive material with a carrier gas;
a delivery system, including an array of lances, configured to introduce an additive-containing fluid, comprising an additive material and carrier gas, into a contaminated gas stream; and
a controller operable, in response to a sensed stimulus associated with an additive deposited in a first lance, to terminate flow of the additive material through the first lance of the lance array but not through at least one other lance of the lance array; while the additive material is not flowing through the first lance, to flow, through the first lance, at least one of a purge gas and a chemical cleaner, to remove at least part of an additive deposited in the first lance; and thereafter commence flow of the additive material through the first lance.
21. The system of claim 20 , wherein the stimulus is at least one of passage of a selected time interval and a measured flow resistance of the additive-containing fluid across a carrier gas/additive mixing system and/or carrier gas/additive delivery system, the carrier gas/additive delivery system comprising the lance array, wherein the at least one of a purge gas and a chemical cleaner is the purge gas, wherein the purge gas has a different characteristic from the carrier gas, the characteristic being one or more of a pressure, composition, temperature, and flow velocity, and wherein the controller is further operable to:
after termination of flow the additive material through the first lance, continue to pass the carrier gas through the first lance to remove at least some additive from the first lance; and
before the purge gas is flowed through the first lance, fluidly isolate the first lance from the carrier gas, whereby flow of the carrier gas through the first lance is terminated while the purge gas flows through the first lance.
22. The system of claim 21 , wherein the purge gas is a compressed gas, wherein flow is additive flow is terminated by shutting off a rotary valve supplying additive to the carrier gas, and wherein the first lance is fluidly isolated by closing a valve positioned between the first lance and the at least one other lance.
23. The system of claim 21 , wherein, while the flow of the additive material is terminated, the first lance is placed in fluid communication with a first sensor, wherein the first sensor measures and provides to a controller a magnitude and/or direction of carrier gas flow or the pressure differential of a duct draw, wherein, based on the first sensor measurement, the controller determines whether additive-containing fluid flow through the first lance is acceptable, wherein, when the additive-containing fluid flow through the first lance is not acceptable, the purge gas flowing operation is performed, and wherein, when the additive-containing fluid flow through the first lance is acceptable, the purge gas flowing operation is not performed.
24. The system of claim 23 , wherein, after the purge gas flowing operation, the first sensor measures and provides to the controller a magnitude and/or direction of carrier gas flow or the pressure differential of a duct draw through the first lance, wherein, based on the first sensor measurement, the controller determines whether additive-containing fluid flow through the first lance is now acceptable after purge gas flow, wherein, when the additive-containing fluid flow through the first lance is not yet acceptable, the purge gas flowing operation is again performed, and wherein, when the additive-containing fluid flow through the first lance is now acceptable, the purge gas flowing operation is not performed again.
25. The system of claim 20 , wherein the at least one of a purge gas and a chemical cleaner is the purge gas, wherein the purge gas has a different characteristic from the carrier gas, the characteristic being one or more of a pressure, composition, temperature, and flow velocity, and wherein the controller is further operable to:
before the terminating and thereafter commencing operations, quantify, parametrically assess, and/or measure a duct draw;
quantify, parametrically assess and/or measure an amount of the purge gas flowed through the first lance; and
determine, based on the results of the quantify, parametrically assess, and/or measure operations, a propensity of the first lance to plug or have reduced flow, the stimulus being dependent on the propensity of the first lance to plug or have reduced flow.
26. The system of claim 20 , wherein the stimulus is at least one of passage of a selected time interval and a measured flow resistance of the additive-containing fluid across the carrier gas/additive mixing system and/or carrier gas/additive delivery system, wherein the at least one of a purge gas and a chemical cleaner is the chemical cleaner, and further comprising:
after termination of flow the additive material through the first lance, continuing to pass the carrier gas with the chemical cleaner through the first lance to remove at least some additive from the first lance.
27. The system of claim 26 , wherein the chemical cleaner is a mineral acid or acid gas.
28. A system, comprising:
a mixing system to mix an additive material with a carrier gas;
a delivery system, including a plurality of lances, configured to introduce an additive-containing fluid, comprising an additive material and carrier gas, into a contaminated gas stream; and
a controller operable, in response to a sensed stimulus associated with an additive deposited in a first lance, to fluidly isolate the first lance from at least one other lance of the plurality of lances and flow, through the first lance but not through the at least one other lance, at least one of a purge gas and a chemical cleaner to remove at least part of an additive deposited in the first lance, wherein, while the at least one of a purge gas and a chemical cleaner flows through the first lance, the additive-containing fluid continues to flow through the at least one other lance.
29. The system of claim 28 , wherein the controller is further operable to:
while the first lance is fluidly isolated, suspend flow of the additive material through the first lance of the lance array but not through at least one other lance of the lance array; and
when the at least part of the additive deposited in the first lance is removed, recommence flow the additive material fluid through the first lance.
30. The system of claim 29 , wherein the stimulus is at least one of passage of a selected time interval and a measured flow resistance of the additive-containing fluid across the carrier gas/additive mixing system and/or carrier gas/additive delivery system, wherein the at least one of a purge gas and a chemical cleaner is the purge gas, wherein the purge gas has a different characteristic from the carrier gas, the characteristic being one or more of a pressure, composition, temperature, and flow velocity, and wherein the controller is further operable to:
after termination of flow the additive material through the first lance, continue to pass the carrier gas through the first lance to remove at least some additive from the first lance; and
before the purge gas is flowed through the first lance, fluidly isolate the first lance from the carrier gas, whereby flow of the carrier gas through the first lance is terminated while the purge gas flows through the first lance.
31. The system of claim 30 , wherein the purge gas is a compressed gas, wherein flow is additive flow is terminated by shutting off a rotary valve supplying additive to the carrier gas, and wherein the first lance is fluidly isolated by closing a valve positioned between the first lance and the at least one other lance.
32. The system of claim 30 , wherein, while the flow of the additive material is terminated, the first lance is placed in fluid communication with a first sensor, wherein the first sensor measures and provides to the controller a magnitude and/or direction of carrier gas flow or the pressure differential of a duct draw, wherein, based on the first sensor measurement, the controller determines whether additive-containing fluid flow through the first lance is acceptable, wherein, when the additive-containing fluid flow through the first lance is not acceptable, the purge gas flowing operation is performed, and wherein, when the additive-containing fluid flow through the first lance is acceptable, the purge gas flowing operation is not performed.
33. The system of claim 32 , wherein, after the purge gas flowing operation, the first sensor measures and provides to a controller a magnitude and/or direction of carrier gas flow or the pressure differential of a duct draw through the first lance, wherein, based on the first sensor measurement, the controller determines whether additive-containing fluid flow through the first lance is now acceptable after purge gas flow, wherein, when the additive-containing fluid flow through the first lance is not yet acceptable, the purge gas flowing operation is again performed, and wherein, when the additive-containing fluid flow through the first lance is now acceptable, the purge gas flowing operation is not performed again.
34. The system of claim 29 , wherein the at least one of a purge gas and a chemical cleaner is the purge gas, wherein the purge gas has a different characteristic from the carrier gas, the characteristic being one or more of a pressure, composition, temperature, and flow velocity, and wherein the controller is further operable to:
before the terminating and thereafter commencing operations, quantify, parametrically assess, and/or measure a duct draw;
quantify, parametrically assess and/or measure an amount of the purge gas flowed through the first lance; and
determine, based on the results of the quantify, parametrically assess, and/or measure operations, a propensity of the first lance to plug or have reduced flow, the stimulus being dependent on the propensity of the first lance to plug or have reduced flow.
35. The system of claim 29 , wherein the stimulus is at least one of passage of a selected time interval and a measured flow resistance of the additive-containing fluid across a carrier gas/additive mixing system and/or carrier gas/additive delivery system, the carrier gas/additive delivery system comprising the lance array, wherein the at least one of a purge gas and a chemical cleaner is the chemical cleaner, and wherein the controller is further operable to:
after termination of flow the additive material through the first lance, continue to pass the carrier gas with the chemical cleaner through the first lance to remove at least some additive from the first lance.
36. The system of claim 35 , wherein the chemical cleaner is a mineral acid or acid gas.