DE29900238U1 - Condensing burner - Google Patents

Description

Bernd Zimmermann
06120 Halle/Saale

Condensing burners

The invention relates to a condensing burner, such as an oil burner, gas burner or a dual fuel burner.

In such burners for heating so-called cryogenic or low-temperature boilers, the combustion air was taken from the environment. These burners with their cryogenic or low-temperature boilers have the disadvantage that they cannot utilize the condensing value or partial condensing value of the fuels in accordance with DIN 5499.

The invention is therefore based on the object of improving the use of calorific value or partial calorific value and achieving a better overall efficiency.

This object is achieved according to the invention by the features of claim 1.

Accordingly, an air preheater is provided for the combustion air in a burner, which is preheated by the exhaust gases from the burner. This is preferably done via a heat exchanger that is located in the exhaust gas flow.

Such a design has the advantage that the temperature of the burner's exhaust gases is even lower. It is also possible to achieve 90% of the annual efficiency with non-designed radiators, eg if the radiators are designed for 55/45 ⁰ C condensing technology.

The heat exchanger in the exhaust gas stream can also be used to increase the return temperature.

The combustion air is sucked in, for example, via the existing combustion air fan and/or by an additional fan.

By utilizing the excess preheated combustion air, it is also possible to ventilate a building with this excess preheated air.

The combustion air in smaller burners no longer has to be taken from the building and preheated again, but can also be taken from the outside air and preheated by the exhaust gases.

The control system for the burner and boiler is equipped with a return temperature limiter to prevent the temperature from falling below the dew point; a possible second burner stage can be controlled via the outside temperature, for example.

The invention is explained in more detail in an embodiment using the drawing. In this:

Figure 1 shows schematically a heating system with a burner according to the

Invention;
Figure 2 is a schematic, partially sectioned view of an exhaust gas heat exchanger for a burner according to the invention.

In Figure 1, 1 is a burner, 2 is a boiler, 3 is an air preheater and 4 is a heat exchanger for raising the return temperature of the heating system. 5 is the flow system for the heating and 6 is the return flow flowing through the heat exchanger 4. According to arrow 7, the exhaust gases from the burner 1 are led through the air preheater 3 and the heat exchanger 4, with excess exhaust gases being discharged via the chimney according to arrow 8.

In the air preheater 3, the combustion air for the burner 1 is preheated by its exhaust gases 7 and fed to the burner via a line 9, only indicated here; the burner sucks in this preheated air through its combustion air fan and/or an additional fan.

Figure 2 shows an exhaust gas heat exchanger for the heating system according to Figure 1; this heat exchanger has an inlet into which the exhaust gases 7 from the burner flow and, after flowing through the heat exchanger, flow in the direction of 8 to the chimney. The heat exchanger raises the return temperature of the return flow 6 from the heating system to the boiler 2 in its part 4 and lowers the exhaust gas temperature; in the part of the heat exchanger that acts as an air preheater 3, the air is led to the burner 1 via an air intake nozzle with a connected line 9.

Fig.1

1: Burner

2: Boiler

3: Air preheater

4: Heat exchanger

5: Heating flow

6: Return

7: Exhaust gas flow

8: Exhaust gas flow chimney

9: preheated combustion air

10: Combustion air intake

11: Return

12: Condensate neutralization Fig. 2

1: preheated combustion air

2: Raising the return temperature

3: Heat exchanger combustion air preheater

4: Heat exchanger return flow increase

5: Boiler connection

6: Connection to pipeline network

7: Boiler exhaust connection

8: Exhaust connection chimney

9: Combustion air connection nozzle preheated exhaust air

10: Combustion air connection nozzle supply air

11: Supply air flow

Claims (4)

Bernd Zimmermann 06120 Halle/Saale Protection claims 1. Condensing burners, such as oil burners, gas burners or dual-fuel burners, in particular for heating cryogenic and low-temperature boilers, characterized in that the burner (1) has an air preheater (3) for the combustion air, which is heated via the exhaust gases (7). 2. Burner according to claim 1, characterized in that the air preheater (3) is designed as a heat exchanger. 3. Burner according to claim 2, characterized in that the heat exchanger has a further region (4) for raising the return temperature of the heating system. 4. Burner according to one of the preceding claims, characterized in that the existing combustion air fan and/or an additional fan is provided for sucking in the burner air.