High-temperature gasification combustion biomass steam generator

Abstract

A high-temperature gasification combustion biomass steam generator comprises a lower furnace body, a main furnace body is located above the front portion of the lower furnace body, a stock bin is arranged on the front portion of the main furnace body, a waste heat recoverer is installed above the rear end of the lower furnace body, a heat exchange water pipe is installed in the waste heat recoverer, and an induced draft fan is connected to a smoke outlet of the preheating recoverer. A high-temperature heat exchanger is arranged in front of the waste heat recoverer, a main boiler body is arranged in front of the high-temperature heat exchanger, a heat exchange pipe is arranged in the high-temperature heat exchanger, a water inlet of the heat exchange pipe is connected to a water outlet of a water pump through a first electronic valve, an outlet of a middle heat exchange pipe is connected to a steam outlet chamber above, and a plurality of snakelike fin heat exchange pipes are arranged on the upper portion in the main boiler body; the lower ends of the snakelike fin heat exchange pipes are connected to the lower collecting pipe, the upper ends of the snakelike fin heat exchange pipes are connected to the upper collecting pipe, steam outlet of the upper collecting pipe is connected to the steam-water separation cavity, and steam outlet of the steam-water separation cavity and steam outlet of the steam outlet chamber are connected to two inlets of the jet device respectively. The steam generator is good in effect.

Description

TECHNICAL FIELD

[0001] The utility model relates to a boiler, especially to a biomass boiler and belongs to the technical field of heat exchange equipment. BACKGROUND

[0002] The biomass steam generator is a heat exchanger using biomass as raw material, and is one of the industries encouraged by the state because of using renewable biomass fuel. The existing biomass steam generator (boiler) generally adopts at least twice air distribution during combustion, so that the biomass combustion is sufficient, but it also brings a problem. Because of excessive air during combustion, a large amount of nitrogen oxides is generated during combustion, resulting in high nitrogen oxide concentration in tail gas. Therefore, how to realize low nitrogen emission of the biomass boiler is a problem to be solved. SUMMARY

[0003] The utility model discloses a high temperature gasification combustion biomass steam generator which overcomes the above problems existing in the prior art.

[0004] In order to realize the purpose of the utility model, the following technical scheme is adopted: a high temperature gasification combustion biomass steam generator, comprising a lower furnace body, a reciprocating or chain type grate is installed in the lower furnace body, a main furnace body is located above the front part of the lower furnace body, a bunker is arranged at the front part of the main furnace body, the discharge end of the bunker is communicated with a feeder, the discharge end of the feeder is located above the grate, an air blower interface is formed in the lower furnace body, the air blower interface is located below the grate in the side view direction, a waste heat recovery device is installed above the rear end of the lower furnace body, a heat exchange water pipe is installed in the waste heat recovery device, an induced draft fan is connected to the smoke outlet of the waste heat recovery device, the water inlet of the heat exchange water pipe of the waste heat recovery device is connected to the water inlet of the steam generator, a high temperature heat exchanger is installed in front of the waste heat recovery device, the main furnace body is in front of the high temperature heat exchanger, a heat exchange pipe is installed in the high temperature heat exchanger, the water inlet of the heat exchange pipe is connected to the water outlet of a water pump through a first electronic valve, the outlet of the intermediate heat exchange pipe is connected to the steam outlet chamber above, a plurality of serpentine fin heat exchange pipes are installed in the main furnace body, the lower end of the serpentine fin heat exchange pipe is connected to a lower header, the upper end is connected to an upper header, the steam outlet of the upper header is connected to a steam-water separation chamber, the steam outlet of the steam-water separation chamber and the steam outlet of the steam outlet chamber are respectively connected to the two inlets of a jet device, wherein the steam-water separation chamber is connected to the jet port, two front and rear distribution baffles are fixedly arranged below the serpentine fin heat exchange pipe in the furnace body, the flue gas generated after combustion on the grate enters between the two baffles, the smoke outlet of the main furnace body is connected to the smoke inlet of the high temperature heat exchanger, the water inlet of the lower header of the main furnace body is connected to the water outlet of the water pump through a second electronic valve, the water inlet of the water pump is connected to the water outlet of the heat exchange water pipe, a heavy hammer safety valve is installed on the steam outlet chamber, a pressure gauge and a safety valve are installed on the upper header.

[0005] Further, the high-temperature heat exchanger is a three-pass heat exchanger with flue gas flowing in the up-down direction, and the first pass, the second pass and the third pass are sequentially arranged from front to back; the lower end of the heat exchange pipe in the third pass is connected to the water outlet of the water pump through a first electronic valve, and the heat exchange medium in the third pass flows from bottom to top; the upper end of the heat exchange pipe in the second pass is connected to the upper end of the heat exchange pipe in the third pass, and the lower end of the heat exchange pipe in the second pass is connected to the lower end of the heat exchange pipe in the first pass; the flue gas inlet of the high-temperature heat exchanger is located at the upper end of the front part in the first pass; the flue gas flow port from the first pass to the second pass is located at the lower end of the rear part of the first pass; the flue gas flow port from the second pass to the third pass is located at the upper end of the rear part of the second pass; and the flue gas flow port from the third pass to the waste heat heat exchanger is located at the lower end of the rear part of the third pass.

[0006] Further, the pulse soot blower is connected with compressed air, and the pulse soot blower is divided into a first branch pipe corresponding to the first pass, a second branch pipe corresponding to the second pass and a third branch pipe corresponding to the third pass; and the pulse soot blower blows high-pressure air to clean the intermediate heat exchanger.

[0007] Further, a settling pipe is arranged between the upper header pipe and the lower header pipe, and the two ends of the settling pipe are communicated with the upper header pipe and the lower header pipe respectively.

[0008] Further, the main furnace body is made of refractory bricks.

[0009] The positive and beneficial technical effects of the steam generator are as follows: the first combustion chamber and the second combustion chamber are formed below and above the baffle respectively, the first combustion chamber is combusted under the air distribution of the air blower, the flue gas formed by combustion enters the second combustion chamber from between the two baffles, no air distribution is formed in the second combustion chamber, radiation combustion under high temperature is formed, an oxygen-deficient environment is formed, the amount of nitrogen entering is obviously reduced due to the significant reduction of air entering, the formation of nitrogen oxides is obviously reduced, the emission of nitrogen oxides in tail gas is reduced, high-pressure steam can be formed by combustion in the main furnace body, and the steam outlet chamber of the high-temperature heat exchanger can form a local low pressure (lower than atmospheric pressure) after the high-pressure steam is connected to the jet port, which is beneficial to steam outlet of the steam outlet chamber and increases the steam outlet of the high-temperature heat exchanger and improves the steam outlet of the whole steam evaporator. BRIEF DESCRIPTION OF DRAWINGS

[0010] Figure 1 It is a whole schematic view of the utility model.

[0011] Figure 2 It is a schematic view of a vertical section in the front-rear direction.

[0012] Figure 3 It is a schematic view of the inside of the main furnace body.

[0013] Figure 4 is a front view schematic diagram of the utility model.

[0014] Figure 5 is a schematic diagram of the upper part of the utility model. DETAILED DESCRIPTION

[0015] In order to more fully explain the implementation of the utility model, the implementation examples of the utility model are provided. These implementation examples are only the elaboration of the utility model, and do not limit the scope of the utility model.

[0016] The utility model is further explained in detail in combination with the drawings, and the various marks in the drawings are as follows: 1: lower furnace body; 2: main furnace body; 3: waste heat recovery device; 4: water outlet of heat exchange water pipe; 5: high-temperature heat exchanger; 6: heat exchange pipe; 7: water inlet of high-temperature heat exchanger; 8: steam outlet chamber; 9: first branch pipe; 10: second branch pipe; 11: third branch pipe; 12: heavy hammer type safety valve; 13: water inlet of main furnace body; 14: steam-water separation cavity; 15: jet device; 16: upper header; 17: stock bin; 18: feeding machine; 19: grate; 20: baffle; 21: serpentine fin heat exchange pipe; 22: smoke outlet; 23: first return stroke; 24: second return stroke; 25: third return stroke; 26: lower header; 27: settling pipe; 28: air blower interface; 29: liquid level meter installation pipe; 30: pulse soot blower.

[0017] The reciprocating or chain type grate in the utility model is the prior art, and the technical solutions disclosed in CN 202868700 U and CN 208170415 U can be adopted. In the utility model, the water pump and the electronic valve are common devices in the prior art boiler, and can be purchased in the market, and are not shown in the drawings.

[0018] As shown in the drawings, a high-temperature gasification combustion biomass steam generator comprises a lower furnace body 1, a grate 19 is installed in the lower furnace body, a main furnace body 2 is located above the front part of the lower furnace body, the main furnace body is piled up with refractory bricks, a bunker 17 is arranged at the front part of the main furnace body, the lower end of the bunker is communicated with a feeder 18, the feeder can be a screw feeder, the discharge of the feeder is located above the grate, an air blower interface 28 is opened on the lower furnace body, the air blower interface is located below the grate in the lateral direction, a waste heat recovery device 3 is installed on the upper part of the rear end of the lower furnace body, heat exchange water pipes are installed in the waste heat recovery device, an induced draft fan is connected to the smoke outlet 22 of the waste heat recovery device, the water inlet of the steam generator is connected to the water inlet end of the heat exchange water pipes, a high-temperature heat exchanger 5 is installed in front of the waste heat recovery device, the high-temperature heat exchanger is in front of the main furnace body 2, heat exchange pipes 6 are installed in the high-temperature heat exchanger, the water inlet of the heat exchange pipes is connected to the water outlet of a water pump through a first electronic valve, the outlet of the heat exchange pipes is connected to an upper steam chamber 8, in the embodiment, the high-temperature heat exchanger is a three-pass heat exchanger with the flue gas flowing in the up-down direction, the first pass 23, the second pass 24 and the third pass 25 are sequentially arranged from front to back, the lower end of the heat exchange pipe in the third pass is connected to the water outlet of the water pump through a first electronic valve, the heat exchange medium in the third pass flows from bottom to top, the upper end of the heat exchange water pipe in the second pass is connected to the upper end of the heat exchange water pipe in the third pass, the lower end of the heat exchange water pipe in the second pass is connected to the lower end of the heat exchange water pipe in the first pass, the flue gas inlet of the high-temperature heat exchanger is located at the upper end of the front part of the first pass, the flue gas flow port from the first pass to the second pass is located at the lower end of the rear part of the first pass, the flue gas flow port from the second pass to the third pass is located at the upper end of the rear part of the second pass, and the flue gas flow port from the third pass to the waste heat recovery device is located at the lower end of the rear part of the third pass.

[0019] A pulse soot blower 30 is installed on the intermediate heat exchanger, the pulse soot blower is connected with compressed air, the pulse soot blower is divided into a first branch pipe 9 corresponding to the first pass, a second branch pipe 10 corresponding to the second pass and a third branch pipe 11 corresponding to the third pass, high-pressure air is blown out through the pulse soot blower to clean the intermediate heat exchanger, the first branch pipe, the second branch pipe and the third branch pipe are communicated to the upper part of the corresponding pass. The pulse soot blower is a prior art.

[0020] A plurality of serpentine finned heat exchange tubes 21 are installed in the upper portion of the main furnace body 2, the lower ends of the serpentine finned heat exchange tubes are connected to the lower header 26, and the upper ends are connected to the upper header 16, the upper header is a steam drum, a downcomer 27 is installed between the upper header and the lower header, the downcomer is also called a descending pipe, the two ends of the downcomer are respectively connected to the upper header and the lower header, the steam outlet of the upper header is connected to the steam-water separation chamber 14, a return pipe is connected between the steam-water separation chamber and the lower header, the steam outlets of the steam-water separation chamber 14 and the steam outlet chamber 8 are respectively connected to the two inlets of the jet flow device 15, wherein the steam-water separation chamber is connected to the jet flow port, two front and rear distribution baffles 20 are fixedly arranged below the serpentine finned heat exchange tubes in the furnace body, the flue gas generated after combustion on the grate enters between the two baffles, the smoke outlet of the main furnace body 1 is connected to the smoke inlet of the high-temperature heat exchanger, the lower header 26 of the main furnace body is connected to the water outlet of the water pump through a second electronic valve, the water inlet of the water pump is connected to the water outlet of the heat exchange water pipe, a heavy hammer type safety valve 12 is installed on the steam outlet chamber, a pressure gauge is also installed on the steam outlet chamber, a pressure gauge and a safety valve are installed on the upper header. A liquid level meter is installed on the steam generator, and 29 represents a liquid level meter installation pipe (upper and lower installation pipes).

[0021] The flow of the heat medium (water, steam) of the steam generator is as follows: the water inlet of the steam generator enters the heat exchange water pipe of the waste heat recovery device for preheating, and after the water outlet of the heat exchange water pipe in the waste heat recovery device (4 in the figure represents the water outlet of the heat exchange water pipe), the water enters the water pump, and the water pump is divided into two routes, the first route is connected to the water inlet 7 of the high-temperature heat exchanger through a first electronic valve, and the second route is connected to the water inlet 13 of the main furnace body through a second electronic valve. The heat medium flows in the heat exchange pipe and exchanges heat with the flue gas in the high-temperature heat exchanger to form a micro-pressure (slightly higher than atmospheric pressure) steam close to atmospheric pressure, and then enters the steam outlet chamber; the heat medium exchanges heat with the high-temperature flue gas in the serpentine finned heat exchange pipe to form a mixture of high-pressure steam and water, which enters the upper header, and then the water and steam are separated in the steam-water separation chamber, the water flows into the upper header from the return pipe and falls into the lower header through the downcomer, the steam outlet of the steam-water separation chamber is connected to the jet flow port of the jet flow device, and the jet flow device is a Venturi tube using the Venturi effect to drive the steam in the steam outlet chamber to flow and form a local low pressure (negative pressure, lower than atmospheric pressure) to accelerate the steam output of the high-temperature heat exchanger. The two routes of steam are mixed and output.

[0022] The flue gas flow of the steam generator is as follows: the fuel falls onto the chain grate and is combusted in the first combustion chamber to form a large amount of flue gas, which enters the second combustion chamber through the inlet between the two baffles, and is combusted by high-temperature radiation and under-oxygen combustion in the second combustion chamber. The flue gas is sequentially guided by the induced draft fan to pass through the first return, the second return, and the third return of the high-temperature heat exchanger, and then enters the waste heat recovery device, and is then discharged through the induced draft port.

[0023] After the embodiments of the present application are described in detail, those skilled in the art can clearly understand that various changes and modifications can be made without departing from the above patent application range and spirit, any simple modification, equivalent change and modification made according to the technical essence of the present application to the above embodiments all belong to the range of the technical scheme of the present application, and the present application is also not limited to the implementation modes of the examples shown in the specification.

Claims

1. A high-temperature gasification combustion biomass steam generator, comprising a lower furnace body, a reciprocating or chain grate is installed in the lower furnace body, a main furnace body is located above the front of the lower furnace body, a bunker is arranged at the front of the main furnace body, the lower end of the bunker is communicated with a feeder, the discharge of the feeder is located above the grate, an air blower interface is opened on the lower furnace body, the air blower interface is located below the grate in the side view direction, a waste heat recovery device is not installed on the rear end of the lower furnace body, a heat exchange water pipe is installed in the waste heat recovery device, an induced draft fan is connected to the smoke outlet of the waste heat recovery device, and a water inlet of the steam generator is connected to a water inlet end of the heat exchange water pipe, characterized in that: The intermediate heat exchanger is installed before the waste heat recovery device, and the main furnace body is installed before the intermediate heat exchanger; the intermediate heat exchanger is provided with heat exchange pipes, the water inlet of the heat exchange pipes is connected to the water outlet of the water pump through a first electronic valve, and the outlet of the intermediate heat exchange pipes is connected to the steam chamber; a plurality of serpentine fin heat exchange pipes are installed in the main furnace body; the lower end of the serpentine fin heat exchange pipes is connected to the lower header, and the upper end is connected to the upper header; the steam outlet of the upper header is connected to the steam-water separation chamber; the steam outlet of the steam-water separation chamber and the steam outlet of the steam chamber are respectively connected to the two inlets of the jet device; the steam-water separation chamber is connected to the jet port; two front and rear baffles are fixedly arranged below the serpentine fin heat exchange pipes in the furnace body; the flue gas generated after combustion on the grate enters between the two baffles; the smoke outlet of the main furnace body is connected to the smoke inlet of the intermediate heat exchanger; the lower header of the main furnace body is connected to the water outlet of the water pump through a second electronic valve; the water inlet of the water pump is connected to the water outlet of the heat exchange water pipe; a heavy hammer safety valve is installed on the steam chamber; a pressure gauge and a safety valve are installed on the upper header.

2. A high temperature gasification combustion biomass steam generator according to claim 1, characterized in that: The intermediate heat exchanger is a three-pass heat exchanger for the flue gas flowing in the up-down direction; the intermediate heat exchanger is sequentially provided with a first pass, a second pass and a third pass from front to back; the lower end of the heat exchange pipes in the third pass is connected to the water outlet of the water pump through a first electronic valve; the heat exchange medium in the third pass flows from bottom to top; the upper end of the heat exchange water pipe in the second pass is connected to the upper end of the heat exchange water pipe in the third pass; the lower end of the heat exchange water pipe in the second pass is connected to the lower end of the heat exchange water pipe in the first pass; the flue gas inlet of the intermediate heat exchanger is located at the upper end of the front part of the first pass; the flue gas flow port from the first pass to the second pass is located at the lower end of the rear part of the first pass; the flue gas flow port from the second pass to the third pass is located at the upper end of the rear part of the second pass; and the flue gas flow port from the third pass to the waste heat recovery device is located at the lower end of the rear part of the third pass.

3. A high temperature gasification combustion biomass steam generator according to claim 1, characterized in that: A pulse soot blower is installed on the intermediate heat exchanger; the pulse soot blower is connected to compressed air; the pulse soot blower is divided into a first branch pipe corresponding to the first pass, a second branch pipe corresponding to the second pass and a third branch pipe corresponding to the third pass; the pulse soot blower blows out high-pressure air to clean the intermediate heat exchanger.

4. A high temperature gasification combustion biomass steam generator according to claim 1, characterized in that: A settling pipe is installed between the upper header and the lower header; the two ends of the settling pipe are respectively connected to the upper header and the lower header.

5. A high temperature gasification combustion biomass steam generator according to claim 1, characterized in that: The main furnace body is made of refractory bricks.

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