Semitronik has introduced an Oxygen Analyzer for boilers.

Combustion Air Control System (CAT)
Principle of Operation: CAT Control System is online monitoring and trimming of the combustion air using intelligent control circuit. This system uses a rugged Zirconium Oxide Sensor (ZrO₂). The faster response speed of the sensor results in the maximum optimisation of FD (forced draft)/ID (induced draft) fan speed, which controls the combustion air to optimise the air to fuel ratio in efficiency zone

Theory: Excess Air % results in dry flue gas loss in the boiler through the chimney, thus increasing fuel bill significantly. Similarly, increase in deficient oxygen % results in high unburns and excessive fuel bills. These unburns, namely CO is highly corrosive gas that corrodes boiler and chimney internally. This implies eroding capital assets and emitting higher pollutant gases to the atmosphere.

Case Study: As per present practice in industry, excess oxygen in dry flue gas will increase fuel consumption by 2 to 5%. Similarly, deficient oxygen will increase fuel consumption by 2 to 3%. Hence it is very important to maintain optimum value of oxygen in maximum efficiency zone.

Any typical industry using combustion equipment spends higher value in capital cost and also fuel bill. By proper tuning of Combustion Air using Semitronik's CAT Control one can substantially minimise this routine expenditure (Reference graph above).

The CAT Control System is a user-friendly product. No need of any extra operator attention. Installation of the system will tune air/fuel ratio at maximum efficiency zone. It reduces dry flue gas loss at stack, unburns of fuel and harmful oxides like NOx, Sox to the chimney. ROI (Return on Investment) to investment will be paid back in less than year and additionally one reduces harmful pollutants gases to the atmosphere.

Combustion Air Trimming is a standard practice in the developed countries; where it is mandatory. Even the Government of India has made it mandatory for all power plants. Soon it may become mandatory in low pressure boiler plants also.

Fine regulation of excess air; Improves heat transfer rate; Tighter smoke emission control; Substantial fuel saving. Ideal for all types of fuels. Continuously matching fuel to air rates on demand; Reduces harmful emissions, lessens pollution.