CZ20033065A3 - Wood waste burning bailer - Google Patents

Abstract

In the present invention, there is disclosed a wood waste burning boiler indented for producing steam or hot water by burning loose or lumpy wood waste. The boiler achieves increased efficiency through utilization of fire tubes (22) with a bundle of tubes (23) inserted therein, wherein cooled water flows in opposite direction to the flow of combustion products within said fire tubes (22).

Description

Technical field ------ - ¹¹

The invention relates to steam and hot water boilers for wood waste incineration.

BACKGROUND OF THE INVENTION

Most steam and hot water boilers are designed to feed fuel to the furnace by screw or belt conveyors, which requires the treatment of wood waste to a loose state / This is best suited to waste from the woodworking industry (sawdust, shavings and small waste).

Wood waste from forest plants must be treated for burning by chipping (larger pieces), or chopping chaotic material (branches, etc.). Because wood chipping is both energy and labor intensive, this method is not of interest to forest plants and most wood waste remains in the forest. According to expert literature, only about 5 million tons of dry matter are used in the Czech Republic in the light of the ongoing climate change in relation to the greenhouse gases generated by the combustion of fossil fuels, the need to burn wood waste is increasingly urgent.

The solution is to develop a boiler with high efficiency and incineration of various types of wood waste: logs, sawdust, bark, shavings and chopped waste of up to 100 mm.

SUMMARY OF THE INVENTION A uniform layer of fine fuel on the sliding grate is provided by a worm mounted in a trough with longitudinal ribs. The height of the layer depends on the screw speed and the grate sliding speed.

Drying the fuel on the grate accelerates the supply of a portion of the flue gas from the boiler outlet chamber to the fan inlet chamber, where it is mixed with primary air and the mixture is blown under the grate.

Drying of the fuel also accelerates the placement of the grate in the focus of the radiant heat of the furnace vault.

The high efficiency of the boiler is ensured by a drum in the upper part of which is a heat pipe with an inserted bundle of pipes. Cooled water from the heating system flows through the pipes upstream of the flue gas. The feed water of the steam boilers can be heated in the same way.

The door can be used for placing larger waste and logs on the grid either manually by hand or by suitable mechanization.

The boiler for efficient and ecological combustion of wood waste in any form of different humidity is shown in Fig. Lyr 3.

DETAILED DESCRIPTION OF THE INVENTION

In Fig. 1 the boiler is shown in longitudinal section. The chain grate 1 is driven by a gearbox 2, a chain gear 3 _x and a sprocket wheel 40. 3. The screw conveyor 5 distributes the fine fuel on the grate X into a layer whose thickness depends on the adjustable screw speed. 5 á Depending on the boiler output required, the feed rate of the grate X is considerable.

The duct 6 ^x FIG. 2 feeds a portion of the flue gas from the outlet chamber 7 to the mixing chamber 8 of the fan 9 which draws in the primary air through the pipe 10 regulated by the flap 28. The flap 11 can control the amount of flue gas. Both flaps 28 and 11 can be adjusted manually or by a servomotor, depending on the boiler output.

V - -V

Mixing the hot flue gas with the primary air _A, yielding a mixture with a low relative humidity, which accelerates the final drying of moist fuel and release of volatile matter.

The recycling of the flue gas into the furnace 12 reduces the temperature in the furnace, thereby extending the lining life and also decreasing the emission ΝΘΧ2 <- - · - -. and ·· The lowering of the flue gas temperature in the furnace has no effect on the overall heat output of the boiler, since it is increased, which increases the flame generator speed <. heat transfer coefficient, thus compensating for the lowered melting / - ^{1 IR} .L'I

The door 13 allows the introduction of lump fuel directly onto the grate. The fan 14 blows secondary air into the furnace / nozzles 15. The amount of secondary air is regulated by the flap 16, according to the boiler output required.

The vault / furnace does not radiate radiant heat to the X-fuel and accelerates gasification and combustion. Spalirjas from the bottom of the heater are blown over the vault by a suction fan 18 where small particles of charcoal carried by the flue gases burn down at low speed.

In the heat pipes 19 of the lower part of the drum 20, the flue gases transfer heat to the water and pass through the chamber 21 into the heat pipes 227. pipes X and max. thermal gradient of cooled water and flue gas reduces the temperature of flue gases and increases the overall efficiency of the boiler up to 85%.

From the outlet chamber 7, the flue gas is blown by the fan 18 through the cyclone ash separator into the chimney. By cooling the flue gas in the heat pipe 22 below 100 (° C), it is possible to use the exhaust fan 18 of the standard design, and at the same time the low flue gas temperature does not reduce the blower pressure.

..................... ....... i

Tubes? (23 ^\? Which are-chamber (24) connected to the inlet (26) cooled in the water chamber (25) and tube (27), the lower space of the drum (20). I '4.

Claims (3)

Claims> 7/7 Wood-burning boiler with increased efficiency and low flue gas temperature, characterized in that the drum (20) is mounted on the furnace (12) so that the lower part of the drum (20) is connected to the furnace (12) and the heat tubes (19) with the transfer chamber (21), in the upper part of the drum (20) are stored the heat tubes (22), which connect the transfer chamber (21) with the outlet chamber (7); (23), which are connected by a chamber (24) to a chilled water inlet (26), a chamber (25) and a pipe (27) with a lower space of the drum (20). A cross-section according to claim 1, characterized in that the mixing chamber (8) of the fan (9) is connected via a conduit (6) to the outlet chamber (7) and the atmospheric air pipe (10) through a discharge port. The fan (9) is connected to the space under the grate (1). V -. ;; ·· '\, ·' 'i-é' -— 3. Apparatus according to Claims 1 and 2, characterized in that the screw conveyor (5) located in front of the furnace (12) and above the grate (1) is provided with an opening at the bottom allowing fuel to fall into the grate (1) and its grate. spreading the screw conveyor (5) on the grate (1) into a layer which is adjustable by changing the speed of the screw conveyor (5) depending on the boiler output, f) n cl; and c Boiler for waste incineration ^ <λ <. ÚIX ': tC'iVt K. (' 'ip tx il The boiler is designed to produce steam or hot water by burning loose or lump wood waste. The boiler achieves increased efficiency by using the heat tubes (22) with an inserted bundle of tubes (23) through which the cooled water flows against the flue gas direction (flame).