Economisers are designed to recover heat from boiler exhaust gasses at the steam, heat or power generation plants. The heating capacity of boiler exhaust gasses are transferred to the incoming boiler feed water, increasing the overall boiler thermal efficiency. The most economical way to improve efficiency of a boiler system is the usage of an economiser behind the boiler. Selnikel has successfully installed almost 7.000 economisers as of today.
Selnikel economiser applications provide;
- Increased boiler efficiency
- Reduced fuel consumption
- Low temperature exhaust gas and reduced emissions
Depending on the fuel type, Selnikel economisers increase boiler thermal efficiency by 3% - 8% and ensure reduced energy consumption, fuel savings and reduced emissions. The end user therefore benefits from a shorter Return on Investment time.
The thermal design of the economiser is performed in accordance with the given parameters of exhaust gas volume and temperature, feedwater volume - temperature and the required flue gas temperature downstream of the economiser. The philosophy of economizer is the same as that of air preheater. According to the size of heating surface and operation conditions, the exhaust gas is cooled down to approximately 50°C.
The economisers can be categorised as follows:
As per economiser material;
- Stainless Steel Economiser
- Carbon Steel Economiser
As per tube type;
- Finned tube type
- Tube type
As per heated fluid type;
- Feed water heater
- Cold/Usage water heater
- Air preheater