An efficient biomass gas hot blast stove

Abstract

The present invention discloses an efficient biomass gas hot blast stove, which includes an adiabatic combustion chamber, a primary temperature adjustment chamber, and a secondary temperature adjustment chamber formed by partitioning the inner wall of the stove body; the adiabatic combustion chamber is provided with a gas burner, a bottom heat storage layer laid at the bottom, and a central fire baffle wall arranged on the bottom heat storage layer and located in the middle of the adiabatic combustion chamber; the gas burner is installed at the front end of the adiabatic combustion chamber, its inlet is used to introduce biomass gas, and its outlet is aligned with the central fire baffle wall; the inlet of the primary temperature adjustment chamber is communicated with the outlet of the adiabatic combustion chamber, the inlet of the secondary temperature adjustment chamber is communicated with the outlet of the primary temperature adjustment chamber, and the outlet of the hot blast stove is connected to an external heat exchange device at the rear end; primary temperature adjustment air pipes are evenly distributed in the primary temperature adjustment chamber, and secondary temperature adjustment air pipes are evenly distributed in the secondary temperature adjustment chamber. The biomass gas of this hot blast stove is sent into the furnace from the burner, and after combustion in the adiabatic combustion chamber, it passes through the primary temperature adjustment chamber and the secondary temperature adjustment chamber in turn, so that the gas burns sufficiently and the flue gas temperature at the outlet of the hot blast stove is controllable.

Description

Technical Field

[0001] The present invention relates to the technical field of drying equipment, and in particular to an efficient biomass gas hot blast stove using biomass gas as a heat source. Background Art

[0002] With the application and popularization of biomass gasification technology, in addition to industrial boilers, more and more industrial kilns have begun to use biomass gasification technology to provide heat sources, and the hot blast stove is one of them. However, the existing hot blast stoves at present are not designed according to the characteristics of biomass gas, resulting in various problems in actual use. Such as a lot of hot air tar, overheating at the dryer inlet, ignition of dried materials, bag dust removal and ignition of the flue gas cloth bag at the tail of the dryer, etc.

[0003] Traditional gas hot blast stoves burn high-calorific value gas fuels and are designed according to the characteristics of high-calorific value fuels, resulting in insufficient combustion space when using biomass gas, high furnace outlet temperature, and affecting the safety of the subsequent drying equipment, dried materials, and environmental protection facilities. Some biomass gas contains liquid tar, and the tar vapor formed by heating the tar in the hot blast stove cannot be burned cleanly, entering the subsequent equipment to affect the dried materials and even emitting black smoke. Summary of the Invention

[0004] The object of the present invention is to overcome the above-mentioned deficiencies of the prior art and provide an efficient biomass gas hot blast stove.

[0005] The present invention is realized by the following technical solutions: An efficient biomass gas hot blast stove includes an adiabatic combustion chamber, a primary temperature adjustment chamber, and a secondary temperature adjustment chamber formed by dividing the inner wall of the furnace body; with one side of the adiabatic combustion chamber as the front end of the furnace body, the adiabatic combustion chamber is provided with a gas burner, a central fire baffle, and a furnace bottom heat storage layer; the furnace bottom heat storage layer is laid on the inner bottom of the adiabatic combustion chamber, the central fire baffle is arranged on the furnace bottom heat storage layer and located in the middle of the adiabatic combustion chamber, and the top of the central fire baffle does not touch the inner wall of the top side of the adiabatic combustion chamber; the gas burner is installed at the front end of the adiabatic combustion chamber, its inlet is used to introduce biomass gas, and its outlet is aligned with the central fire baffle; the inlet of the primary temperature adjustment chamber is communicated with the outlet of the adiabatic combustion chamber, the inlet of the secondary temperature adjustment chamber is communicated with the outlet of the primary temperature adjustment chamber, the outlet of the secondary temperature adjustment chamber is the outlet of the hot blast stove, and the outlet of the hot blast stove is connected to an external heat exchange device at the back end; the primary temperature adjustment chamber is evenly distributed with primary temperature adjustment air ducts for providing air volume for it, and the secondary temperature adjustment chamber is evenly distributed with secondary temperature adjustment air ducts for providing air volume for it.

[0006] After the biomass gas enters the furnace, it burns stably in the adiabatic combustion chamber. The heat storage layer at the bottom of the furnace can enable the tar flowing into the furnace to evaporate and burn quickly; the high-temperature flue gas further reduces the temperature of the flue gas step by step through the primary temperature control chamber and the secondary temperature control chamber, controlling the cooling rate of the flue gas, providing process adjustment for denitrification in the furnace, and having sufficient time to mix evenly; the flue gas area formed between the adiabatic combustion chamber, the primary temperature control chamber, and the secondary temperature control chamber forms a tortuous channel, extending the residence time of the flue gas in the furnace, helping to improve the burnout rate, and reducing the temperature of the flue gas leaving the furnace.

[0007] The gas burner is inclined and arranged on the adiabatic combustion chamber, and the height of its inlet is higher than the height of its outlet. The inclined gas burner can enable the tar contained in the gas to flow smoothly into the furnace, avoiding being blocked by tar during the operation of the gas burner. On the other hand, it can give the gas an initial downward combustion velocity, extend the residence time of the gas in the furnace, shorten the flame length, and improve the burnout rate.

[0008] The adiabatic combustion chamber is provided with a bottom air supply pipe, and the bottom air supply pipe is located above the heat storage layer at the bottom of the furnace and is aligned with the central fire baffle. The bottom air supply pipe can supplement the air volume required for tar combustion, avoiding the destruction of the combustion dynamic field in the furnace due to the competition for air between tar vapor and biomass gas.

[0009] The central fire baffle is provided with a number of through holes penetrating its front and back sides. The central fire baffle with through holes can prevent the biomass gas flame from being too long, increase the temperature at the front end of the adiabatic combustion chamber, enable the gas to burn cleanly in the hot blast stove, and play a role in stabilizing combustion.

[0010] The outlet of the adiabatic combustion chamber is located in the upper part of the furnace body, the outlet of the primary temperature control chamber is located in the lower part of the furnace body, and the outlet of the hot blast stove is located in the upper part of the furnace body; a denitrification device is installed in the outlet of the adiabatic combustion chamber. The settings of the positions of the outlet of the adiabatic combustion chamber, the outlet of the primary temperature control chamber, and the outlet of the hot blast stove make the channels formed in the three chambers have a longer path, allowing the flue gas to have a longer residence time, so as to have sufficient time to mix evenly.

[0011] It further includes a air supply device for supplying air volume to the primary temperature control air duct and the secondary temperature control air duct. The setting of the air supply device enables the high-temperature flue gas to be cooled down twice in the primary temperature control chamber and the secondary temperature control chamber.

[0012] The air supply device includes a cold air connection pipe, an air volume regulating valve for the conditioning chamber, a primary air volume distribution valve for regulating the air volume of the primary temperature regulating air duct, and a secondary air volume distribution valve for regulating the air volume of the secondary temperature regulating air duct; the primary temperature regulating air duct and the secondary temperature regulating air duct are respectively connected to the cold air connection pipe, the primary air volume distribution valve is installed on the pipe between the primary temperature regulating air duct and the cold air connection pipe, the secondary air volume distribution valve is installed on the pipe between the secondary temperature regulating air duct and the cold air connection pipe, the air volume regulating valve for the conditioning chamber is installed on the cold air connection pipe, and the cold air connection pipe is installed on the outer wall of the furnace body. The air volume of the primary temperature regulating air duct is adjusted by the primary air volume distribution valve, the air volume of the secondary temperature regulating air duct is adjusted by the secondary air volume distribution valve, and the air volume regulating valve for the conditioning chamber can control the air volume distribution of the primary conditioning chamber and the secondary conditioning chamber to adapt to the load change of the hot blast stove and provide a guarantee for process regulation of auxiliary measures such as denitration.

[0013] There are two layers of the primary temperature regulating air ducts evenly distributed in the upper and lower parts of the primary temperature regulating chamber, namely the first-level primary temperature regulating air duct and the second-level primary temperature regulating air duct, and the first-level primary temperature regulating air duct is located in the upper layer. There are two levels of primary temperature regulating air ducts evenly distributed in the upper and lower parts of the primary temperature regulating chamber, so as to control the flue gas cooling rate, provide process regulation for in-furnace denitration, and have sufficient time to mix evenly.

[0014] There are two layers of the secondary temperature regulating air ducts evenly distributed in the upper and lower parts of the secondary temperature regulating chamber, namely the first-level secondary temperature regulating air duct and the second-level secondary temperature regulating air duct, and the first-level secondary temperature regulating air duct is located in the lower layer. There are two levels of secondary temperature regulating air ducts evenly distributed in the upper and lower parts of the secondary temperature regulating chamber, which can effectively and evenly reduce the flue gas temperature, control the outlet temperature of the hot blast stove, and avoid various problems caused by over-temperature of the flue gas at the rear-end equipment.

[0015] The number of the primary temperature regulating air ducts is greater than that of the secondary temperature regulating air ducts. The temperature in the primary temperature regulating chamber is higher than that in the secondary temperature regulating chamber. Using more temperature regulating air ducts can effectively and quickly cool the high-temperature flue gas.

[0016] Compared with the prior art, the advantages of the present invention are as follows: The biomass gas of this hot blast stove is sent into the furnace from the burner, and after combustion in the adiabatic combustion chamber, it passes through the primary conditioning chamber and the secondary conditioning chamber in turn, so that the gas burns sufficiently and the outlet flue gas temperature of the hot blast stove is controllable; it has higher efficiency, is safe and reliable; it can effectively solve problems such as more hot blast tar, over-temperature at the dryer inlet, ignition of dried materials, bag dust collector clogging and ignition of the flue gas at the dryer tail. Brief Description of the Drawings

[0017] Figure 1 is a structural perspective view of an embodiment of the present invention;

[0018] Figure 2 is a top view of an embodiment of the present invention;

[0019] Figure 3 This is a schematic structural diagram of the air supply device according to an embodiment of the present invention.

[0020] Meanings of the reference numerals in the figure: 1, adiabatic combustion chamber; 2, primary temperature control chamber; 3, secondary temperature control chamber; 101, gas burner; 102, central fire baffle; 103, bottom heat storage layer of the furnace; 104, bottom air supply pipe of the furnace; 201, primary primary temperature control air duct; 202, secondary primary temperature control air duct; 301, primary secondary temperature control air duct; 302, secondary secondary temperature control air duct; 4, hot blast stove outlet; 5, cold air connection pipe; 501, air volume regulating valve for the temperature control chamber; 502, primary air volume distribution valve; 503, secondary air volume distribution valve. Specific embodiments

[0021] The content of the present invention will be further described in detail below in conjunction with the drawings and specific embodiments.

[0022] Embodiment

[0023] Refer to Figures 1 to 3 , which is a high-efficiency biomass gas hot blast stove, including an adiabatic combustion chamber 1, a primary temperature control chamber 2, and a secondary temperature control chamber 3 formed by dividing the inner wall of the furnace body; taking one side of the adiabatic combustion chamber 1 as the front end of the furnace body, the adiabatic combustion chamber 1 is provided with a gas burner 101, a central fire baffle 102, and a bottom heat storage layer 103; the bottom heat storage layer 103 is laid on the inner bottom of the adiabatic combustion chamber 1, the central fire baffle 102 is arranged on the bottom heat storage layer 103 and is located in the middle of the adiabatic combustion chamber 1, and the top of the central fire baffle 102 does not touch the inner wall of the top side of the adiabatic combustion chamber 1; the gas burner 101 is installed at the front end of the adiabatic combustion chamber 1, its inlet is used for introducing biomass gas, and its outlet is aligned with the central fire baffle 102; the inlet of the primary temperature control chamber 2 is communicated with the outlet of the adiabatic combustion chamber 1, the inlet of the secondary temperature control chamber 3 is communicated with the outlet of the primary temperature control chamber 2, the outlet of the secondary temperature control chamber 3 is the hot blast stove outlet 4, and the hot blast stove outlet 4 is connected to the externally connected heat exchange equipment at the rear end; the primary temperature control air ducts for providing air volume for it are evenly distributed in the primary temperature control chamber 2, and the secondary temperature control air ducts for providing air volume for it are evenly distributed in the secondary temperature control chamber 3.

[0024] After the biomass gas enters the furnace, it stably burns in the adiabatic combustion chamber 1, and the bottom heat storage layer 103 can enable the tar flowing into the furnace to evaporate and burn quickly; the high-temperature flue gas further reduces the temperature of the flue gas step by step through the primary temperature control chamber 2 and the secondary temperature control chamber 3, so as to control the cooling speed of the flue gas, provide process adjustment for denitrification in the furnace, and have sufficient time to mix evenly; the flue gas area formed between the adiabatic combustion chamber 1, the primary temperature control chamber 2, and the secondary temperature control chamber 3 forms a tortuous channel, which prolongs the residence time of the flue gas in the furnace, helps to improve the burnout rate, and reduces the temperature of the flue gas leaving the furnace.

[0025] The gas burner 101 is inclined and installed on the adiabatic combustion chamber 1, and the height of its inlet is higher than that of its outlet. The inclined installation of the gas burner 101 can enable the tar contained in the gas to flow smoothly into the furnace, avoiding blockage of the gas burner 101 by tar during operation. On the other hand, it can give the gas an initial downward combustion velocity, prolong the residence time of the gas in the furnace, shorten the flame length and improve the burnout rate.

[0026] The adiabatic combustion chamber 1 is provided with a bottom air supply pipe 104, and the bottom air supply pipe 104 is located above the bottom heat storage layer 103 and aligned with the central fire baffle 102. The bottom air supply pipe 104 can supplement the air volume required for tar combustion, avoiding the destruction of the combustion dynamic field in the furnace due to the competition for air between tar vapor and biomass gas.

[0027] The central fire baffle 102 is provided with a number of through holes that penetrate its front and rear sides. The central fire baffle 102 with through holes can prevent the biomass gas flame from being too long, increase the temperature at the front end of the adiabatic combustion chamber 1, enable the gas to burn cleanly in the hot blast stove, and play a role in stabilizing combustion.

[0028] The outlet of the adiabatic combustion chamber 1 is located in the upper part of the furnace body, the outlet of the primary temperature adjustment chamber 2 is located in the lower part of the furnace body, and the outlet 4 of the hot blast stove is located in the upper part of the furnace body; a denitration device is installed inside the outlet of the adiabatic combustion chamber 1. The settings of the positions of the outlet of the adiabatic combustion chamber 1, the outlet of the primary temperature adjustment chamber 2, and the outlet 4 of the hot blast stove make the channels formed in the three chambers have a longer path, allowing the flue gas to have a longer residence time, so that there is sufficient time to mix evenly.

[0029] It also includes an air supply device for supplying air volume to the primary temperature adjustment air pipe and the secondary temperature adjustment air pipe. The setting of the air supply device enables the high-temperature flue gas to be cooled twice in the primary temperature adjustment chamber 2 and the secondary temperature adjustment chamber 3.

[0030] The air supply device includes a cold air connection pipe 5, a temperature adjustment chamber air volume regulating valve 501, a primary air volume distribution valve 502 for regulating the air volume of the primary temperature adjustment air pipe, and a secondary air volume distribution valve 503 for regulating the air volume of the secondary temperature adjustment air pipe; the primary temperature adjustment air pipe and the secondary temperature adjustment air pipe are respectively connected to the cold air connection pipe 5, the primary air volume distribution valve 502 is installed on the pipe between the primary temperature adjustment air pipe and the cold air connection pipe 5, the secondary air volume distribution valve 503 is installed on the pipe between the secondary temperature adjustment air pipe and the cold air connection pipe 5, the temperature adjustment chamber air volume regulating valve 501 is installed on the cold air connection pipe 5, and the cold air connection pipe 5 is installed on the outer wall of the furnace body. The air volume of the primary temperature adjustment air pipe is adjusted by the primary air volume distribution valve 502, the air volume of the secondary temperature adjustment air pipe is adjusted by the secondary air volume distribution valve 503, and the temperature adjustment chamber air volume regulating valve 501 can control the air volume distribution of the primary temperature adjustment chamber 2 and the secondary temperature adjustment chamber 3 to adapt to the load change of the hot blast stove and provide a guarantee for process adjustment for auxiliary measures such as denitration.

[0031] There are two layers of primary temperature adjustment air ducts evenly distributed in the upper and lower parts of the primary temperature adjustment chamber 2, namely the first-level primary temperature adjustment air duct 201 and the second-level primary temperature adjustment air duct 202. The first-level primary temperature adjustment air duct 201 is located in the upper layer. There are two levels of primary temperature adjustment air ducts evenly distributed in the upper and lower parts of the primary temperature adjustment chamber 2, which controls the cooling speed of the flue gas, provides process adjustment for in-furnace denitration, and has sufficient time to mix evenly.

[0032] There are two layers of secondary temperature adjustment air ducts evenly distributed in the upper and lower parts of the secondary temperature adjustment chamber 3, namely the first-level secondary temperature adjustment air duct 301 and the second-level secondary temperature adjustment air duct 302. The first-level secondary temperature adjustment air duct 301 is located in the lower layer. There are two levels of secondary temperature adjustment air ducts evenly distributed in the upper and lower parts of the secondary temperature adjustment chamber 3, which can effectively and evenly reduce the flue gas temperature, control the temperature at the outlet 4 of the hot blast stove, and avoid various problems caused by over-temperature flue gas in the backend equipment.

[0033] The number of primary temperature adjustment air ducts is greater than the number of secondary temperature adjustment air ducts. The temperature in the primary temperature adjustment chamber 2 is higher than that in the secondary temperature adjustment chamber 3. Using more temperature adjustment air ducts can effectively and quickly cool down the high-temperature flue gas.

[0034] The flame of biomass gas combustion is relatively long. When passing through the central fire wall 102 in the adiabatic combustion chamber 1, it forms multiple streams. Part of it passes through the wall through multiple channel holes on the central fire wall 102, and part bypasses the wall from the upper part of the central fire wall 102, increasing the residence time of biomass gas in the furnace, stabilizing the temperature at the front end of the adiabatic combustion chamber 1, enabling the gas to burn cleanly and stably in the hot blast stove, and on the other hand, preventing the biomass gas flame from being too long and avoiding the flame from burning in the primary temperature adjustment chamber 2.

[0035] The flue gas after combustion enters the primary temperature adjustment chamber 2 through the outlet of the adiabatic combustion chamber 1. A denitration device is set at the outlet of the adiabatic combustion chamber 1 to control the generation of combustion pollutants.

[0036] The high-temperature flue gas is cooled by the first-level primary temperature adjustment air duct 201 in the primary temperature adjustment chamber 2, and the flue gas gradually drops to 800 - 850 °C. The preliminarily cooled flue gas is cooled by the second-level primary temperature adjustment air duct 202, further reducing the flue gas temperature. However, the distance between the two temperature adjustment zones controls the cooling speed of the flue gas, provides process adjustment for in-furnace denitration, and has sufficient time to mix evenly. The first-level primary temperature adjustment air duct 201 and the second-level primary temperature adjustment air duct 202 of the temperature adjustment air duct adjust the air volume through the primary air volume distribution valve 502.

[0037] The cooled flue gas coming out of the primary temperature adjustment chamber 2 enters the secondary temperature adjustment chamber 3. The flue gas cooled by the first-level secondary temperature adjustment air duct 301 and the second-level secondary temperature adjustment air duct 302 then enters the drying flue gas pipeline through the outlet 4 of the hot blast stove, and then enters the backend heat exchange equipment to heat the materials that require hot air. The first-level secondary temperature adjustment air duct 301 and the second-level secondary temperature adjustment air duct 302 adjust the air volume through the secondary air volume distribution valve 503.

[0038] After passing through the two-stage secondary temperature adjustment air ducts, the flue gas temperature can be effectively and evenly reduced, and the flue gas temperature at the outlet 4 of the hot blast stove can be controlled to avoid various problems caused by over-temperature of the flue gas in the backend equipment.

[0039] The primary temperature adjustment air duct and the secondary temperature adjustment air duct are connected by a cold air connection pipe 5. The cold air connection pipe 5 is provided with a temperature adjustment chamber air volume regulating valve 501. The air volume distribution of the primary temperature adjustment chamber 2 and the secondary temperature adjustment chamber 3 is controlled through the temperature adjustment chamber air volume regulating valve 501 to adapt to the load change of the hot blast stove and the change of the flue gas temperature requirement at the outlet 4 of the hot blast stove, and to provide a guarantee for process adjustment for auxiliary measures such as denitration.

[0040] The above detailed description is a specific description of the feasible embodiments of the present invention. These embodiments are not intended to limit the patent scope of the present invention. Any equivalent implementation or modification without departing from the present invention shall be included in the patent scope of this case.

Claims

1. An efficient biomass gas hot blast stove, characterized in that: It includes an adiabatic combustion chamber, a primary temperature adjustment chamber, and a secondary temperature adjustment chamber formed by partitioning the inner wall of the furnace body. Taking one side of the adiabatic combustion chamber as the front end of the furnace body, the adiabatic combustion chamber is provided with a gas burner, a central fire baffle, and a furnace bottom heat storage layer. The furnace bottom heat storage layer is laid on the inner bottom of the adiabatic combustion chamber. The central fire baffle is arranged on the furnace bottom heat storage layer and is located in the middle of the adiabatic combustion chamber. The top of the central fire baffle does not touch the inner wall of the top side of the adiabatic combustion chamber. The gas burner is installed at the front end of the adiabatic combustion chamber. Its inlet is used to introduce biomass gas, and its outlet is aligned with the central fire baffle. The inlet of the primary temperature adjustment chamber is communicated with the outlet of the adiabatic combustion chamber. The inlet of the secondary temperature adjustment chamber is communicated with the outlet of the primary temperature adjustment chamber. The outlet of the secondary temperature adjustment chamber is the outlet of the hot blast stove, and the outlet of the hot blast stove is connected to an external heat exchange device at the rear end. The primary temperature adjustment chamber is evenly distributed with primary temperature adjustment air ducts for supplying air volume to it. The secondary temperature adjustment chamber is evenly distributed with secondary temperature adjustment air ducts for supplying air volume to it. The gas burner is inclined and arranged on the adiabatic combustion chamber, and the height of its inlet is higher than the height of its outlet. The adiabatic combustion chamber is provided with a furnace bottom air supply pipe, and the furnace bottom air supply pipe is located above the furnace bottom heat storage layer and is aligned with the central fire baffle.

2. The high-efficiency biomass gas hot blast stove according to claim 1, wherein: The central fire baffle is provided with a number of channel holes penetrating through its front and rear sides.

3. The high-efficiency biomass gas hot blast stove according to claim 1, wherein: The outlet of the adiabatic combustion chamber is located in the upper part of the furnace body. The outlet of the primary temperature adjustment chamber is located in the lower part of the furnace body. The outlet of the hot blast stove is located in the upper part of the furnace body. A denitration device is installed inside the outlet of the adiabatic combustion chamber.

4. The high-efficiency biomass gas hot blast stove according to claim 1, characterized in that: It also includes an air supply device for supplying air volume to the primary temperature adjustment air ducts and the secondary temperature adjustment air ducts.

5. The high-efficiency biomass gas hot blast stove according to claim 4, characterized in that: The air supply device includes a cold air connection pipe, a temperature adjustment chamber air volume regulating valve, a primary air volume distribution valve for regulating the air volume of the primary temperature adjustment air duct, and a secondary air volume distribution valve for regulating the air volume of the secondary temperature adjustment air duct. The primary temperature adjustment air duct and the secondary temperature adjustment air duct are respectively connected to the cold air connection pipe. The primary air volume distribution valve is installed on the pipe between the primary temperature adjustment air duct and the cold air connection pipe. The secondary air volume distribution valve is installed on the pipe between the secondary temperature adjustment air duct and the cold air connection pipe. The temperature adjustment chamber air volume regulating valve is installed on the cold air connection pipe, and the cold air connection pipe is installed on the outer wall of the furnace body.

6. The high-efficiency biomass gas hot blast stove according to claim 1, wherein: There are two layers of the primary temperature adjustment air ducts evenly distributed in the upper and lower parts of the primary temperature adjustment chamber, namely a first-level primary temperature adjustment air duct and a second-level primary temperature adjustment air duct, and the first-level primary temperature adjustment air duct is located in the upper layer.

7. The high-efficiency biomass gas hot-blast stove according to claim 1, wherein: There are two layers of the secondary temperature adjustment air ducts evenly distributed in the upper and lower parts of the secondary temperature adjustment chamber, namely a first-level secondary temperature adjustment air duct and a second-level secondary temperature adjustment air duct, and the first-level secondary temperature adjustment air duct is located in the lower layer.

8. The high-efficiency biomass gas hot blast stove according to claim 1, wherein: The number of the primary temperature adjustment air ducts is greater than the number of the secondary temperature adjustment air ducts.

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