Revamps 2022 Issue

1 Imbalances typically found in combustion process: Extremely variable (loading scenario) Related to unbalanced design and operation of air/fuel supply system Introducing operational limitations in results of optimisation strategies 2 Poor available monitoring: 1 or 2 points for excess oxygen at the exit of the heater: – Measure does not represent actual O values used by burners – Distorted by ‘air in-leakages’ Fuel and combustion air globally supplied

Results

Excess oxygen

Negative eects Eciency Emissions (CO, NO , CO, etc.) Corrosion fouling Tubes overheating, coking Operational safety x

Air

Fuel

Typical monitoring capabilities

Fuel/air global supply

Figure 1 Industrial furnaces and boilers: background

As illustrated in Figure 2 , the following elements are used in this integrated approach: • Advanced monitoring technologies • Regulation capabilities improvement • Expert system for optimised combustion control. Advanced monitoring technologies Monitoring the local in-furnace combustion conditions makes surveillance possible, which is essential for imple - menting optimised operating scenarios. This monitoring guides the operator to obtain the best tuning of any indi - vidual burner and, therefore, overall optimisation of the combustion unit. ABACO-Opticom technology characterises the flue gas concentration profiles (O₂, CO, CO₂, NO X , SO 2 ) in the enve- lope of each burner while avoiding the application of inter - polation software or averaged results. Gas samples are individually taken and are not affected by the fuel typology or boiler configuration. Sampling probes can be fixed, non-cooled, or retractable water-cooled (see Figure 3 ); both are designed to withstand any temperatures within the furnace at the required sampling points. The use of ABACO-Opticom results in the identification of operating issues, such as significant fuel and air imbalances between furnace areas that can give rise to: • High CO levels

1 Combustion monitoring: ABACO-Opticom (O, CO, CO, NO, etc.) Temperatures

3 Expert system for closed- loop combustion control

Air

2 Air / fuel regulation improvement

Fuel

Figure 2 ABACO technology elements: solution for combustion optimisation

This approach turns out to be a cost-effective alterna- tive to the retrofit of the combustion system (for example, burner substitution) or a valuable complementary tool after the retrofit has been completed. Applying this technology to an existing combustion unit requires minimum modifica - tions and a very limited outage period for the new equip - ment implementation.

Figure 3 ABACO-Opticom technology sampling probes (options: fixed non-cooled or retractable water-cooled)

Revamps 2022