Biomass pretreatment system

Abstract

The utility model discloses a biomass pretreatment system, which includes a dryer, a milling machine, and a roaster, wherein the discharge port of the dryer is connected to the feed port of the roaster; the discharge port of the roaster is connected to the feed port of the milling machine; the roaster is used to roast the biomass to be milled to remove the moisture of the biomass and destroy the cellulose and hemicellulose structure of the biomass. The biomass pretreatment system provided by the utility model can effectively remove the moisture of the biomass raw material and destroy its cellulose and hemicellulose structure, greatly reducing the difficulty of grinding, and the quality of the biomass carbon powder produced by the system is more stable and controllable.

Description

Technical Field

[0001] The utility model relates to the fields of chemical industry, environmental protection and new energy, and in particular to a biomass pretreatment system. Background Art

[0002] Biomass is a rich renewable resource, including wood, straw, waste plants, crop residues, etc. The processing and utilization of biomass has important economic and environmental significance. Among them, the straw of crops such as wheat and rice, as an important type of biomass resources, is produced in huge quantities during agricultural production, but most of the straw is not fully utilized at present.

[0003] Biomass milling is a process that converts biomass raw materials into powder products. It is usually used in the fields of biomass energy production, animal feed processing, and chemical raw material preparation. However, there are still some problems in the current biomass milling process that limit its widespread application and further development, mainly including the following aspects: (1) Since the quality and properties of biomass raw materials are affected by factors such as the growth environment, harvest season, and storage method, the quality of the raw materials will be unstable, which in turn affects the quality and stability of the milled products; (2) The presence of cellulose and hemicellulose may make the texture of the particles after grinding uneven, resulting in problems such as different particle sizes and irregular shapes in the granular materials, thus affecting the quality and stability of the particles; (3) Due to the high hardness of cellulose and hemicellulose, the equipment used for grinding and crushing is easily subject to severe wear, resulting in a reduction in equipment life and an increase in maintenance costs; (4) The fibers of straw biomass are long and intertwined, which may form fiber clumps or fiber knots in the grinding equipment, leading to equipment blockage and shutdown.

[0004] In view of the above problems, there is an urgent need for a biomass milling system and method with high efficiency, low energy consumption and stable quality, especially for biomass resources such as crop straw such as wheat and rice, so as to improve their utilization rate, reduce resource waste and promote the sustainable use of biomass resources. Utility Model Content

[0005] In order to overcome the above problems, the utility model provides a biomass pretreatment system. The biomass pretreatment system provided by the utility model can effectively remove moisture from biomass raw materials and destroy their cellulose and hemicellulose structures, greatly reducing the difficulty of grinding, and the quality of biomass carbon powder produced by the system is more stable and controllable.

[0006] The utility model solves the above technical problems through the following technical solutions:

[0007] The utility model provides a biomass pretreatment system, comprising a dryer and a powder making machine, characterized in that the biomass pretreatment system also includes a roaster, the discharge port of the dryer is connected to the feed port of the roaster; the discharge port of the roaster is connected to the feed port of the powder making machine; the roaster is used to roast the biomass to be powdered to remove moisture from the biomass and destroy the cellulose and hemicellulose structures of the biomass.

[0008] In this scheme, after the biomass to be powdered is dried by the dryer and input into the roaster, the remaining moisture in the biomass is fully removed, and at the same time the cellulose and hemicellulose structures of the biomass are destroyed, the biomass is carbonized, and the grindability of the material is improved.

[0009] In some preferred embodiments, the biomass pretreatment system also includes a carrier gas circulation module, which includes a circulating fan and a carrier gas heater, the air inlet of the circulating fan is connected to the air outlet of the dryer, the air outlet of the circulating fan is connected to the air inlet of the carrier gas heater, and the air outlet of the carrier gas heater is connected to the air inlet of the dryer.

[0010] In some preferred embodiments, the biomass pretreatment system further comprises a water washing tower, the air inlet of the water washing tower is connected to the air outlet of the dryer, and the air outlet of the water washing tower is connected to the air inlet of the circulating fan.

[0011] In some preferred embodiments, the biomass pretreatment system further comprises a dust collector, the air inlet of the dust collector is connected to the air outlet of the dryer, the air outlet of the dust collector is connected to the air inlet of the water scrubber; and the material outlet of the dust collector is connected to the material inlet of the roaster.

[0012] In some more preferred embodiments, the dust collector is a bag dust collector.

[0013] In some preferred embodiments, the dust collector is further provided with a gas inlet for introducing gas into the dust collector.

[0014] In some preferred embodiments, the water washing tower is further provided with a water inlet for introducing water for spraying into the water washing tower.

[0015] In some preferred embodiments, a relaxation gas outlet is further provided between the circulation fan and the carrier gas heater for regulating the content of water and gas in the carrier gas circulation module.

[0016] In some preferred embodiments, the biomass pretreatment system also includes a tail gas treatment module, which includes a tail gas incinerator and a waste heat recovery device, the air outlet of the roaster is connected to the air inlet of the tail gas incinerator, and the air outlet of the tail gas incinerator is connected to the air inlet of the heat source pipeline of the waste heat recovery device.

[0017] In this solution, the outer surface or interior of the dryer and the roaster is provided with a pipeline for connecting to the cold source pipeline of the waste heat recovery device. The saturated steam and superheated steam heated by heat exchange in the cold source pipeline can be reused in the dryer and the roaster to meet the heat consumption required by the dryer and the roaster.

[0018] In some preferred embodiments, the tail gas treatment module further comprises a desulfurization and denitration device, and an air inlet of the desulfurization and denitration device is connected to an air outlet of a heat source pipeline of the waste heat recovery device.

[0019] In some preferred embodiments, the exhaust gas treatment module further comprises a separator, the air inlet of the separator is connected to the air outlet of the roaster, and the air outlet of the separator is connected to the air inlet of the exhaust gas incinerator.

[0020] In some more preferred embodiments, the separator is a cyclone separator.

[0021] In some preferred embodiments, the biomass pretreatment system further comprises a slag cooler, the discharge port of the roaster is connected to the feed port of the slag cooler, the discharge port of the slag cooler is connected to the feed port of the powder making machine; the discharge port of the separator is connected to the feed port of the slag cooler.

[0022] On the basis of conforming to the common sense in the art, the above-mentioned preferred conditions can be arbitrarily combined to obtain the preferred embodiments of the present utility model.

[0023] The positive and progressive effects of the utility model are:

[0024] (1) The biomass pretreatment system provided by the utility model can effectively remove moisture from biomass raw materials and destroy their cellulose and hemicellulose structures, greatly reducing the difficulty of grinding and making the quality of the obtained biomass carbon powder more stable and controllable; at the same time, it improves the fluidity of the product, which is conducive to subsequent air flow transportation in industrial production (such as in an entrained bed and a gasification furnace).

[0025] (2) The biomass pretreatment system provided by the utility model can greatly reduce the operating cost. By reasonably setting the circulating carrier gas module and the waste heat recovery device, the utility consumption of the carrier gas and the heat consumption required in the powder making system are greatly reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a schematic diagram of the process flow of the biomass pretreatment system of Example 1 of the utility model.

[0027] Description of reference numerals:

[0028] Dryer 1

[0029] Dust Collector 2

[0030] Water washing tower 3

[0031] Circulation fan 4

[0032] Carrier gas heater 5

[0033] Roaster 6

[0034] Separator 7

[0035] Tail gas incinerator 8

[0036] Waste heat recovery device 9

[0037] Desulfurization and denitrification device 10

[0038] Slag cooler 11

[0039] Flour Milling Machine 12

[0040] Gas inlet 21

[0041] Water inlet 31

[0042] Release gas outlet 41 DETAILED DESCRIPTION

[0043] The specific implementation methods of the present invention are further described below in conjunction with the accompanying drawings. It should be noted that the description of these implementation methods is used to help understand the present invention, but does not constitute a limitation of the present invention. In addition, the technical features involved in each implementation method of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0044] Example 1

[0045] This embodiment provides a biomass pretreatment system, specifically a biomass milling system, such as Figure 1 As shown, the biomass pretreatment system includes a dryer 1 and a powder making machine 12. The system also includes a roaster 6. The discharge port of the dryer 1 is connected to the feed port of the roaster 6. The discharge port of the roaster 6 is connected to the feed port of the powder making machine 12. The roaster 6 is used to roast the biomass to be powdered to remove moisture from the biomass and destroy the cellulose and hemicellulose structures of the biomass.

[0046] In this embodiment, the biomass pretreatment system also includes a carrier gas circulation module, which includes a circulating fan 4 and a carrier gas heater 5. The air inlet of the circulating fan 4 is connected to the air outlet of the dryer 1, the air outlet of the circulating fan 4 is connected to the air inlet of the carrier gas heater 5, and the air outlet of the carrier gas heater 5 is connected to the air inlet of the dryer 1.

[0047] In this embodiment, the biomass pretreatment system also includes a water washing tower 3 and a dust collector 2; the air inlet of the dust collector 2 is connected to the air outlet of the dryer 1, and the air outlet of the dust collector 2 is connected to the air inlet of the water washing tower 3; the air outlet of the water washing tower 3 is connected to the air inlet of the circulating fan 4; the discharge port of the dust collector 2 is connected to the feed port of the roaster 6.

[0048] In other embodiments, when the biomass pretreatment system is not provided with a dust collector 2 , the air inlet of the water washing tower 3 is connected to the air outlet of the dryer 1 .

[0049] In this embodiment, the dust collector 2 is a bag dust collector.

[0050] In this embodiment, the dust collector 2 is further provided with a gas input port 21 for introducing gas into the dust collector 2. The gas input port 21 is used to introduce initial carrier gas and / or supplementary carrier gas into the carrier gas circulation module, and the gas flows through the biomass raw material in the dryer 1 through the carrier gas circulation module, thereby accelerating the drying of the biomass raw material.

[0051] In this embodiment, the water washing tower 3 is further provided with a water inlet 31 for introducing water for spraying into the water washing tower.

[0052] In this embodiment, a relaxation gas outlet 41 is further provided between the circulation fan 4 and the carrier gas heater 5 for regulating the content of water and gas in the carrier gas circulation module.

[0053] In this embodiment, the biomass pretreatment system also includes a tail gas treatment module, which includes a tail gas incinerator 8 and a waste heat recovery device 9. The air outlet of the roaster 6 is connected to the air inlet of the tail gas incinerator 8, and the air outlet of the tail gas incinerator 8 is connected to the air inlet of the heat source pipeline of the waste heat recovery device 9.

[0054] In this embodiment, the outer surface or interior of the dryer 1 and the baking machine 6 is provided with a pipeline for connecting to the cold source pipeline of the waste heat recovery device 9. The saturated steam and superheated steam heated by heat exchange in the cold source pipeline can be reused in the dryer 1 and the baking machine 6 to meet the heat consumption required by the dryer 1 and the baking machine 6.

[0055] In other embodiments, when the tail gas incinerator 8 and the waste heat recovery device 9 are integrated devices, a heat exchange surface is arranged on the flue gas channel in the tail gas incinerator 8, including an evaporator and a superheater. When the flue gas passes through, it exchanges heat with water to produce saturated steam, and exchanges heat with steam to produce superheated steam.

[0056] In this embodiment, the tail gas treatment module further includes a desulfurization and denitration device 10 , and an air inlet of the desulfurization and denitration device 10 is connected to an air outlet of a heat source pipeline of the waste heat recovery device 9 .

[0057] In this embodiment, the tail gas treatment module further includes a separator 7 , the air inlet of the separator 7 is connected to the air outlet of the roaster 6 , and the air outlet of the separator 7 is connected to the air inlet of the tail gas incinerator 8 .

[0058] In this embodiment, the separator 7 is a cyclone separator.

[0059] In this embodiment, the biomass pretreatment system also includes a slag cooler 11, the discharge port of the roaster 6 is connected to the feed port of the slag cooler 11, the discharge port of the slag cooler 11 is connected to the feed port of the powder making machine 12; the discharge port of the separator 7 is connected to the feed port of the slag cooler 11.

[0060] The workflow of the biomass pretreatment system of the utility model is as follows:

[0061] The biomass raw material enters the dryer 1 from the feed port of the dryer 1, and the initial carrier gas (such as nitrogen) enters the biomass pretreatment system from the gas input port 21, and is processed by the bag filter 2, the water scrubber 3, the circulating fan 4 and the carrier gas heater 5 in sequence to form a dry carrier gas. The dry carrier gas enters the dryer 1 from the air inlet of the dryer 1, and the moisture in the biomass raw material is evaporated by heat and is carried out from the air outlet of the dryer 1 by the dry carrier gas and then enters the bag filter 2. The biomass dust carried by the gas in the bag filter 2 is discharged from the discharge port of the bag filter 2 to the roaster 6. The gas in the bag filter 2 enters the water scrubber 3 from the air outlet of the bag filter 2, and the water vapor carried by the gas is discharged from the water scrubber 3. The biomass raw materials entering the dryer will carry a certain amount of air, which will increase the oxygen concentration in the carrier gas. At the same time, the water vapor in the carrier gas after passing through the dryer will inevitably be saturated, and it is necessary to control the moisture content to prevent condensation. The moisture content control depends on the dew point temperature designed in the actual application. The gas in the system is discharged and the carrier gas is supplemented through the relaxation gas outlet 41 and the gas input port 21, respectively, so that the total amount of oxygen and water content in the carrier gas is controlled within 10%.

[0062] The dried biomass is discharged from the discharge port of the dryer 1 and enters the roaster 6. In the roaster 6, the biomass undergoes a pyrolysis reaction to become a biomass roasting product and releases roasting gas. The roasting gas enters the cyclone separator 7 from the air outlet of the roaster 6 to remove solid particles entrained in the roasting gas. The solid particles are discharged from the discharge port of the cyclone separator 7 and enter the slag cooler 11. The roasting gas enters the exhaust gas incinerator 8 from the air outlet of the cyclone separator 7 for incineration. The flue gas after incineration enters the waste heat recovery device 9 to recover heat, and then the cold flue gas enters the desulfurization and denitrification device to remove sulfur, chlorine and nitrogen.

[0063] The biomass roasted product is discharged from the discharge port of the roaster 6 and enters the slag cooler 11 for cooling. The cooled biomass roasted product enters the powder making machine 12 to be made into biomass carbon powder.

[0064] Although the specific embodiments of the present invention are described above, those skilled in the art should understand that these are only examples, and the protection scope of the present invention is defined by the appended claims. Those skilled in the art may make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but these changes and modifications fall within the protection scope of the present invention.

Claims

1. A biomass pretreatment system, comprising a dryer and a pulverizer, characterized in that: The biomass pretreatment system also includes a roaster, the discharge port of the dryer is connected to the feed port of the roaster; the discharge port of the roaster is connected to the feed port of the mill; the roaster is used to roast the biomass to be milled to remove moisture from the biomass and destroy the cellulose and hemicellulose structures of the biomass.

2. The biomass pretreatment system according to claim 1, characterized in that: The biomass pretreatment system also includes a carrier gas circulation module, which includes a circulation fan and a carrier gas heater. The air inlet of the circulation fan is connected to the air outlet of the dryer, the air outlet of the circulation fan is connected to the air inlet of the carrier gas heater, and the air outlet of the carrier gas heater is connected to the air inlet of the dryer.

3. The biomass pretreatment system according to claim 2, characterized in that: The biomass pretreatment system further comprises a water washing tower, an air inlet of the water washing tower is connected to an air outlet of the dryer, and an air outlet of the water washing tower is connected to an air inlet of the circulating fan.

4. The biomass pretreatment system according to claim 3, characterized in that: The biomass pretreatment system further comprises a dust collector, the air inlet of the dust collector is connected to the air outlet of the dryer, and the air outlet of the dust collector is connected to the air inlet of the water washing tower; The discharge port of the dust collector is connected to the feed port of the baking machine.

5. The biomass pretreatment system according to claim 4, characterized in that: The dust collector is also provided with a gas inlet for introducing gas into the dust collector; And / or, the water washing tower is further provided with a water inlet for introducing water for spraying into the water washing tower.

6. The biomass pretreatment system according to claim 2, characterized in that: A relaxation gas outlet is also provided between the circulation fan and the carrier gas heater for regulating the content of water and gas in the carrier gas circulation module.

7. The biomass pretreatment system according to claim 1, characterized in that: The biomass pretreatment system also includes a tail gas treatment module, which includes a tail gas incinerator and a waste heat recovery device. The air outlet of the roaster is connected to the air inlet of the tail gas incinerator, and the air outlet of the tail gas incinerator is connected to the air inlet of the heat source pipeline of the waste heat recovery device.

8. The biomass pretreatment system according to claim 7, characterized in that: The tail gas treatment module further comprises a desulfurization and denitration device, and an air inlet of the desulfurization and denitration device is connected to an air outlet of a heat source pipeline of the waste heat recovery device.

9. The biomass pretreatment system according to claim 7, characterized in that: The tail gas treatment module further comprises a separator, the air inlet of the separator is connected to the air outlet of the roaster, and the air outlet of the separator is connected to the air inlet of the tail gas incinerator.

10. The biomass pretreatment system according to claim 9, characterized in that: The biomass pretreatment system further comprises a slag cooler, the discharge port of the roaster is connected to the feed port of the slag cooler, and the discharge port of the slag cooler is connected to the feed port of the powder making machine; The discharge port of the separator is connected to the feed port of the slag cooler.

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