RU172520U1 - Fluidized bed solid fuel boiler with liquid fuel burner - Google Patents

Abstract

The utility model relates to the field of heat power. A boiler unit consists of a mechanical furnace device in the form of a narrow, movable, grate inclined to the horizon, realizing the technology of burning fuel in a high-temperature fluidized bed, heating surfaces, fuel feeder, ejector. The supply of solid fuel is carried out by a mechanical feeder on the accelerating plate and further into the furnace. A gas-tight screen is made in the convective beam, which ensures a turn of the gases in a vertical plane. A two-stage air supply is applied. Primary air goes under the grill, and the secondary air goes into the superlayer space. Using an air ejector, the ablation is returned to the furnace for afterburning. In the combustion chamber along the grate, an additional heating surface is installed, a cooling panel included in the boiler circulation circuit. The cooling panel is made of a series of pipes, placed one above the other, and has a U-shaped layout in plan. In the upper screen of the combustion device, a burner is installed to burn liquid fuel. Liquid fuel is supplied to the burner by means of a fuel line.

Description

The technical result of the claimed utility model is to ensure the kindling of the boiler in automatic mode and to enable the boiler to run on liquid and solid fuels.

The utility model relates to the field of heat power engineering.

Known boiler for burning coal [Smirnov A.V. and others. A boiler unit for the combustion of coal in a fluidized bed. Utility Model Patent. Registered in the State Register of Utility Models of the Russian Federation on May 20, 2004 No. 38041, bull. No. 14], consisting of a mechanical furnace device in the form of a narrow movable grate for inclining the horizon to burn solid fuel in a high-temperature fluidized bed, heating surfaces, fuel feeder, ejector. The heating surfaces have gas tight screens that provide a gas turn to organize the ablation return system. Air is supplied under the grate and into the superlayer space, in the combustion chamber along the grate there is an additional heating surface included in the boiler circulation circuit.

This analogue has several disadvantages:

1. The lack of automatic kindling of the furnace after the complete cessation of its operation in the event of a long stop and cooling for repair or preservation of the boiler, or during a short stop and cooling during temporary shutdown of heat energy consumers;

2. There is no possibility of switching to the reserve type of fuel in the absence of the main one, which reduces the reliability of heat supply to consumers;

The disadvantages of the prototype set the task of the utility model:

- increase the level of automation of the boiler and increase the reliability of heat supply to consumers of thermal energy.

The essence of the claimed utility model is that a boiler for burning solid fuel in a fluidized bed with a burner for burning liquid fuel, consisting of a mechanical furnace device in the form of a movable grate for tilting solid fuel in a high temperature fluidized bed, heating surfaces, a feeder, inclined to the horizon fuel, ejector, with heating surfaces in the form of gas-tight screens, providing a gas turn for the organization of the ablation return system, with air supply under the grate and in the suction oa space, with an additional heating surface along the grate included in the boiler circulation circuit. In the furnace device, on the upper screen, a burner for burning liquid fuel is installed, directed towards the blast zones of the primary air of the grate.

The technical result of the claimed utility model is to ensure the kindling of the boiler in automatic mode and to enable the boiler to run on liquid and solid fuels.

Providing the kindling of the boiler in automatic mode and ensuring the possibility of the boiler working on liquid and solid fuel is solved due to the fact that a burner for burning liquid fuel is installed in the upper screen of the combustion device. This decision is due to the fact that, due to the presence of a burner, it becomes possible to carry out automatic ignition of solid fuel due to the torch formed during the combustion of liquid fuel. Secondly, the use of liquid fuel as a backup makes it possible to diversify the supply of fuel and create a reserve, and also increases the reliability of heat supply to the consumer by providing the ability to quickly change the type of fuel for the boiler.

The proposed boiler design is not identified from the existing level of technology. This allows us to conclude that it meets the criterion of "novelty."

The proposed design of the boiler is illustrated by a figure on a sheet of graphic materials. Coal burning boiler, consisting of a mechanical furnace device made in the form of a movable grate grate (1) inclined to the horizon for burning fuel in a high-temperature fluidized bed, heating surfaces (2, 3) having gas tight screens (4, 5), which provide gas reversal for organizing an ablation return system, an air ejector (6), which provides the entrainment feed to the furnace for afterburning, a fuel feeder (7), which provides gravitational fuel supply, and air supply under the grate in the superlayer space, in the combustion chamber along the grate, an additional heating surface (8) is installed, which is included in the boiler circulation circuit, characterized in that a burner for burning liquid fuel (10) is installed in the upper screen (9) of the furnace device.

To burn fuel, a mechanical furnace device is used in the form of a movable grate, inclined to the horizon, which implements the technology of burning fuel in a high-temperature fluidized bed. According to this technology, the fuel layer is blown by an intense stream of air supplied from below through the grate. In this case, the fuel particles begin to mix intensively. Due to the active mixing of coal particles, intensive washing with air, quick removal of the crust of ash from the outer surface of the pieces of fuel, it is possible to burn the combustible mass by 98-99%. High speed of blast air significantly reduces losses from mechanical incompleteness of fuel combustion with failure. This allows this boiler to work with high efficiency on low-grade coals with high ash content, humidity, low heat of combustion, a large number of small fractions.

The narrow grill is less prone to jamming due to distortions and thermal expansions, easier to operate and repair.

A gas-tight screen is made in the convective beam, which ensures a turn of the gases in a vertical plane. This makes it possible to precipitate particles of slag and unburned fuel carried away from the furnace.

An air ejector transports ablation into the furnace for afterburning. This increases the efficiency of fuel burnout, transfers part of the ablation to slag and reduces emissions of particulate matter with flue gases.

A two-stage air supply is applied. Air is directed under the grill and into the superlayer space. The air supplied to the superlayer space forms a screen (air surface) preventing the entrainment of particles of dispersed material, which increases the efficiency of fuel combustion and reduces the loss of heat with entrainment.

Fuel is supplied by a mechanical feeder to the accelerating plate, from where it enters the furnace under the influence of gravitational forces. The exception of the rotary spreader simplifies the design, increases the reliability of the work.

In the combustion chamber along the grate, an additional heating surface is installed, a cooling panel included in the boiler circulation circuit. The cooling panel is made of a series of pipes placed close to each other. Each pipe has a U-shaped layout in plan. An additional heating surface provides active control of the temperature level of the fluidized bed, prevents the ash from melting, slagging of the grate, which ensures an increase in the efficiency of fuel combustion and an increase in heat output.

This device also includes a fuel oil burner (10). With automatic start-up, the boiler will be kindled by a torch directed towards the blast zones of the primary air of the grate (1), which is formed during the combustion of liquid fuel. At the same time, the torch will ignite solid fuel located on the grate (1).

When working on the main type of fuel, it is possible to use automatic ignition using a burner. After the ignition is completed, the oil burner shuts off. When working on a backup fuel (liquid fuel), the burner does not turn off during the entire working cycle of the boiler.

The above allows us to conclude that the criterion of "industrial use".

List of sources used.

1. Smirnov A.V. and others. A boiler unit for the combustion of coal in a fluidized bed. Utility Model Patent. Registered in the State Register of Utility Models of the Russian Federation on May 20, 2004 No. 38041, bull. Number 14

Claims (1)

A boiler for burning solid fuel in a fluidized bed with a burner for burning liquid fuel, consisting of a mechanical furnace device in the form of a movable grate for tilting solid fuel in a high temperature fluidized bed inclined to the horizon, heating surfaces, fuel feeder, ejector, with heating surfaces in the form gas-tight screens providing a gas turn for the organization of the ablation return system, with air supply under the grate and in the superlayer space, with an additional surface eva along the lattice included in the boiler circulation circuit, characterized in that in the combustion apparatus, the upper screen is mounted burner for burning liquid fuel directed toward the blow primary air zones of the grate.

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