GAS-FIRED POWER PLANTS
Recover efficiency losses in boilers and HRSGs via online cleaning.
Gas-Fired Boilers
CCGT HRSGs
COMBUSTION CHAMBER
Eliminate slagging and improve
heat transfer.
FS12 removes slagging from the tube walls and converts it to dry, friable powder. This results in increased heat transfer and restored capacity.
SUPERHEATERS
Prevent high temperature corrosion
ECONOMISER
Limit fouling and maintain flue gas velocity
BAGHOUSE FILTER
Improve performance and reduce maintenance
AIR PRE-HEATER
Prevent dew point corrosion from sulphuric acid
ESP
Improve particulate removal and reduce cleaning time
STACK
Reduce NOx, SOx and
Carbon emissions
INDUCED DRAFT FAN
Improve performance and
prevent corrosion
After Therma-Chem treatment the hard deposits were removed from the radiant section and all sulphurous deposits were eliminated from the economiser and air pre-heater. As a result, boiler efficiency improved by 0.65% – equivalent to a third of the total efficiency loss prior to treatment.
Therma-Chem’s FS12 is an mildly alkaline solution containing nitrates that is designed specifically to clean boilers online. Using Therma-Chem’s proprietary injection system, the liquid is injected directly into the combustion chamber, vaporises and is carried by the flue gas through the unit, encountering all heat transfer surfaces including the waterwalls, superheaters, economiser and air pre-heater .
FS12 reacts with existing hard deposits and fouling on tubes by increasing their melting point and reduces them to soft powdery ash.
This allows units to maintain high thermal efficiencies or recover capacity (if this was limited by fouling). FS12 also neutralises sulphur deposits on the cold end of the flue gas path preventing cold end corrosion and eases man entry during a maintenance or inspection shutdown.
In addition, FS12 will reduce NOx, SOx and Carbon emissions via efficiency improvements.
Using FS12 ultimately results in improved heat transfer, prevention of both high temperature and low temperature corrosion, improved operating efficiency and reduced emissions.
MAINTENANCE DOSING
Applied daily, FS12 keeps units clean and prevents costly drop offs in performance and avoids the possible need for shutdowns during the operating campaign. This is the most common method of application with some customers having used Therma-Chem every day for 15 years across multiple units.
ON-LINE RECOVERY CLEANING
When a unit is load and/or temperature restricted mid-run and there is no window to shut down for maintenance, FS12 is introduced to recover performance. Injected 3-4 times per day over a period of 30-90 days, depending on the severity of the fouling, FS12 can target any part of the unit loosening deposits and restoring performance. We would then recommend switching to Maintenance Dosing to prevent a drop-off in performance recurring.
PRE-SHUTDOWN CLEANING
Utilised in the run up to a shutdown to facilitate a more effective and easier clean of a unit, FS12 can be applied 3-4 times per day for a period between 30 – 90 days.This ensures that during the shutdown, cleaning is more effective, easier, quicker and any and sulphuric deposits are neutralised, dry, and entry into all areas of the unit is safe and comfortable.