Section 1: Precipitator Chemical Injection Flashcards
What four parameters do the chemical controllers constantly look at?
Load above 200 MW
Temp above 270 F
Opacity above 14% or Load above 325 MW
Either ID fan Running
Why does the temperature run higher on the “AB” than the “CD”?
AB has a longer run of ductwork
- Which chemical injection has the smallest run of duct work?
CD
- What should an operator check on the chemical system?
Breaker Racked In Valves are open Pumps are On and in Auto Flow thru flow meters Chemical Tank Level Leaks Air Dryer Shield air blowers operating
- List some common problems and solutions.
Breakers not Racked in Shield Air blowers not working Plugged lances/ nozzles Low air pressure Low water pressure Low chemical levels Low Flow Chemical, water, or water booster pumps not working Leaks Supply valves for water and chemical valved in Distribution valves valved in
- What is the purpose of the chemical injection system?
The chemical injection sprays the ash to give it an electrical charge to allow better collection on the precipitator.
- What type of water is used with the injection system?
Condensate
- What are the temperature restrictions for operation of this system?
The system must operate above 270 degrees F
- What would be an indication of a plugged lance?
High Air Flow, Low Water Flow
- What is the purpose of the Atomizing air on this system?
To create a fine mist of the chemical mixture
- If the Control Room Operator calls and is having trouble with Opacity what can be done with the injection system to help?
Breaker Racked In Check Chemical tank level Check injection pumps are operational Check for leaks Check Air Dryer system Check Shield Air Blowers Check for plugged lances
- Why must this system not be operated under the temperature restrictions?
It will cause a buildup of ash inside the ductwork
- At midnight what are the extra duties of the outside operator regarding this system?
The operator must check Chemical Storage Tank levels on the DCS and report them on eLog
- How does this chemical help with opacity?
The chemical gives the ash an electrical charge, helping it stick to the precipitator’s plates and wires allowing for better collection
- How many Chemical Injection pumps do we have?
2 Chemical pumps, 2 water pumps and 1 condensate booster pump
