The subject of the invention is a high-temperature gas-fired burner. According to the invention, the burner can be used in industrial combustion systems, combustion chambers of power generation boilers, or steam generators.

Patent literature describes a number of types of gas-fired burners, including burners fired with low-calorific gas and pyrolitic gas.

A structural solution in the form of a burner used for powering a rotary furnace which, in turn, produces clinker-based cement, is known from patent description PL190798. In this solution, the pilot burner is located centrally in the burner axis. Fuel is supplied via a middle ring channel, and the air is supplied through two external channels, which are arranged primarily concentrically and around the fuel line; the portion of the air in one of the air lines flows primarily axially, whereas the portion of the air in the second air line contains the air that has a component of rotation around the central axis of the burner, and the amount of primary air in the said two parts is controlled independently.

Patent document PL 296849 describes another known solution used for powering heating furnaces, in which gaseous fuel is supplied via an outer ring, and an oxidizing agent is supplied via an internal channel. This burner has been designed for standardised gaseous fuel, and after ignition, the burner burns in an autonomous manner.

The manner of combustion and the burner for burning pyrolitic gases, described in patent document PL 363413, is also known, characterised in that it contains an internal sleeve with a diffuser, the outer sleeve, and three middle sleeves. The internal sleeve and the external sleeve, as well as the three middle sleeves, form channels, including the internal channel that supplies pyrolitic waste gas for burning, the adjacent middle channel that supplies primary air to the diffuser, and the further two middle channels that supply natural gas and air for burning, whereas the open external channel is used for supplying secondary air. In the described solution, it was assumed that the gas derived from the pyrolysis process is low-calorific, and it is supplied via an internal channel, whereas a high-calorific gas, e.g. methane, is supplied via one of the external rings. The use of the pilot burner is not necessary since the mixture is enriched with methane and burns spontaneously. Process gas flows through the diffuser, the use of which has an adverse effect on contaminated streams, due to their possible clogging.

The solutions used so far, however, pose a problem with clogging of the nozzles by heavy hydrocarbons condensing inside.

The essence of the invention is a high-temperature gas-fired burner having a main burner and a pilot burner, an air inlet pipe and a fuel inlet pipe, and a ring channel that supplies fuel, characterised in that it has a main burner and a pilot burner with adjustable power, positioned centrically on the mounting plate, in the housing of the main burner. In the housing of the main burner, around the pilot burner there is an internal, ring-type fuel inlet channel, and an external, ring-type air inlet channel. At the end of the internal ring-type fuel inlet channel, there is a fuel gap with an adjustment thread, and the said fuel gap is equipped with fuel swirling blades. At the end of the external ring-type air inlet channel, there is an air gap equipped with air swirling blades. The ring-type fuel inlet channel has an electric heating coil.

The main advantage of the subject of the invention is that it provides a continuous, stable flame of hot pyrolitic gas. Due to its simplified structure, the solution is free of problems with nozzle clogging.

An example embodiment of the invention has been schematically presented in the drawing, in which Fig. 1 shows the entire device in side view,

Fig. 2 - the inlet pipes of the device, Fig. 3 - a longitudinal section of the burner, and Fig. 4 - across-section of the burner.

The embodiment of the invention as per Fig. 1-3 applies to the pyrolysis process. As a result of the pyrolysis process conducted in a classical manner, three types of products are obtained: a gaseous stream, a liquid stream, and solid products. When the process is directed so that the maximum possible amount of gaseous products is generated, it is beneficial to direct the entire gaseous stream directly to the gas burner, avoiding cooling of the gaseous stream and condensation of heavy hydrocarbons. Gases with high temperatures in the range of 200-800°C, derived from the pyrolysis process, contain components of varying composition, which include heavy hydrocarbons. These gases, when cooled, partly condense. The use of a high-temperature burner makes it possible to carry out the combustion process at a temperature so high that there is no need for a complicated gas cleaning system, and the waste fraction of heavy hydrocarbons is not formed.

The high-temperature gas-fired burner has a main burner 1a and a pilot burner 1 with adjustable power, positioned centrically on the mounting plate 2 in the housing of the main burner 1a. The air is supplied to the main burner 1a via an air inlet pipe 10, and the fuel is supplied via a fuel inlet pipe 10a. In the housing of the main burner 1a, around the pilot burner 1, there is an internal, ring-type fuel inlet channel 8 and an external, ring-type air inlet channel 9. At the end of the internal ring-type fuel inlet channel 8, there is a fuel gap 4 equipped with fuel swirling blades 6. At the end of the external ring-type air inlet channel 9, there is an air gap 5 equipped with air swirling blades 7. The ring-type fuel inlet channel 8 has an electric heating coil not shown in the drawing. The fuel gap 4 has an adjustment thread 3. Both the gaps 4 and 5 act as nozzles.

The process of combustion of high-temperature gases consists in supplying the gas derived from the pyrolysis process into the gas inlet channel 8, and then into the fuel gap 4 with a flow rate of 5 to 1000 m3. Via air inlet channel 9, the air in the total amount needed for combustion is also supplied, and at the outlet of both the channels, there are fuel swirling blades 6 and air swirling blades 7. The fuel gap 4 is, additionally, resistively heated to avoid condensation of heavy hydrocarbons during starting and extinguishing of the system.

The pilot burner 1 is positioned centrically on the mounting plate 2 in the housing of the main burner, and functions both as the source of ignition, and the element that stabilises the combustion of high-temperature gas. The pilot burner can be fired with natural gas, LPG or fuel oil. Furthermore, the burner allows continuous power adjustment, depending on steam pressure in steam generators or temperature in boilers. The air and the fuel are supplied to the main burner 1a through the inlet pipes 10 and 10a, and through the ring-type fuel inlet channel 8 and the ring-type air inlet channel 9. As for the combustion chamber, the air and the fuel are supplied to the said chamber via two gaps - the external fuel gap 4 and the internal air gap 5. On each of the gaps 4 and 5, swirling blades 6 and 7 are installed. The fuel gap 4 provides the possibility to adjust the opening size with the adjustment thread 3, and this allows for coarse adjustment of the burner's power, thereby ensuring a wide operating range. The main burner 1a, due to the applied continuous power adjustment for the pilot burner 1, allows working with gases with calorific value of less than 1000 kcal/m3 - i.e. the gases that cannot spontaneously combust - as well as with gases with calorific value of more than 1000 kcal/m3, that undergo spontaneous combustion. This feature is essential during starting and extinguishing of the system, when the gases with low heating value are produced, whereas when the process is already underway, the pilot burner 1 can be completely turned off or work at a minimum power. The function of the pilot burner 1 is not only to support and stabilise the work of the main flame, but also to select an adequate level of power - through the continuous power adjustment - so as to provide the required operating parameters (temperature, steam pressure) of the heat receiver, i.e. a boiler or steam generator.

The burner fired with pyrolitic gas worked for 800 hours. No fluctuations in the operation of the burner were detected, and after its disassembly and dismantling, no deposits of heavy hydrocarbons, that result from combustion of low-quality fuel, were observed. After 1000 hours, the burner was not clogged.

According to the invention, the burner is characterised by simple design and absence of complex stabilising and swirling elements, the result of which is simple manufacturing and low production costs. The burner also allows for adjustment of the size of the fuel gap 4 in the main burner. An initial adjustment is all that it takes to adapt the burner to the gas obtained in the system. The ring-type gas inlet channel 8, via which the fuel is supplied, has an electric heating coil installed, which is useful at the stage of starting and extinguishing the operation of the system. Electric resistive heating is aimed at minimising the possibility of clogging the burner by hydrocarbons that undergo condensation.