CN110616099A - Device and method for preparing biomass fuel by using crop straws - Google Patents

Abstract

The application provides equipment and a method for preparing biomass fuel by using crop straws. The equipment comprises a crusher, a feeder, a dryer, an extrusion molding machine, a lifter, a carbonization device, a conveyor and a packing machine, wherein the carbonization device comprises a carbonization furnace, a calcining furnace and a cooler. The method adopts the process of raw material → pulverization → drying → molding → carbonization → cooling → packaging to prepare the biomass fuel. In the process of preparing the biomass fuel, the crop straws are subjected to pre-carbonization, carbonization and calcination treatment with reasonable control of temperature and time, and the formed biomass fuel is not easy to break and crack. The biomass fuel prepared by the equipment and the method has the advantages of small volume, convenient storage and transportation, cleanness and sanitation, and lower sulfur content and ash content than pulverized coal, can be directly used for civil and industrial fuel boilers, can be supplied to industrial production, rural greenhouses, poultry houses, vegetable greenhouses, drying chambers and the like, and can also be applied to industries such as metallurgy, chemical industry, environmental protection, electric power and the like.

Description

Device and method for preparing biomass fuel by using crop straws

Technical Field

The invention relates to the technical field of crop recycling, in particular to equipment and a method for preparing biomass fuel by using crop straws.

Background

The crop straws generally mainly comprise grain crop straws, oil crop straws, cotton stalks, hemp stalks, sugar residues, sugar crop stem and leaf tips, tobacco stems, vegetable and melon vines, residues and the like. The crop straw contains rich nitrogen, phosphorus, potassium, calcium, organic matters and the like, and is a renewable biological resource, so the crop straw is usually used for preparing coarse feed for poultry and livestock.

The biomass fuel is the fourth largest energy source second only to coal, petroleum and natural gas, and accounts for 14% of the total energy consumption in the world. The biomass fuel can be prepared from agricultural and forestry wastes such as crop straws, sawdust and rice chaff, wherein the resource amount of the crop straws accounts for about half of the raw material for preparing the biomass fuel.

At present, in the technology of preparing biomass fuel by using crop straws, a preparation process of firstly carbonizing and then molding is generally adopted. The structure of the crop straw is damaged in the carbonization process, the extrusion forming characteristic of the straw can be improved during extrusion forming, and the mechanical abrasion and energy consumption of a forming part can be reduced, so that the preparation process of firstly carbonizing and then forming is a common preparation process. However, as the structure of the crop straws is damaged in the carbonization process, the carbonized straw carbon block is loose and fragile. After the biomass fuel is formed by extrusion molding of the straw carbon blocks, the biomass fuel is difficult to maintain a given shape due to the loose and fragile straw carbon blocks, so that the biomass fuel is easy to crack or break in the storage and transportation processes, and the quality of the biomass fuel is affected.

Disclosure of Invention

The invention provides equipment and a method for preparing biomass fuel by using crop straws, which aim to solve the problem that the biomass fuel prepared by the conventional equipment and method is easy to crack or break.

The invention provides equipment for preparing biomass fuel by using crop straws, which comprises: the device comprises a crusher, a feeder, a dryer, an extrusion molding machine, a lifter, a carbonization device, a conveyor and a packaging machine which are sequentially connected according to the inlet and outlet sequence of crop straws; the carbonization device comprises a pre-carbonization furnace, a calcining furnace and a cooler which are sequentially connected, the pre-carbonization furnace is connected with the hoisting machine, and the cooler is connected with the conveyor.

Preferably, the shredder comprises a shredder housing and a shredding chamber located inside the shredder housing; a crusher rotating shaft and an annular screen are arranged in the crushing chamber, and the crusher rotating shaft is positioned in the center of the annular screen; the outside of rubbing crusher pivot is equipped with the hammer leaf, the annular screen cloth towards one side of rubbing crusher pivot is equipped with the pinion rack.

Preferably, the dryer comprises a dryer shell, and a steam inlet pipe and a steam outlet pipe which are arranged on the surface of the dryer shell; a rotary disc shaft is arranged in the dryer shell, and a hollow disc is arranged on the rotary disc shaft; the rotating disc shaft is respectively communicated with the disc, the steam inlet pipe and the steam outlet pipe.

Preferably, the inner surface of the dryer shell is also provided with a scraper.

Preferably, the extrusion molding machine comprises a molding machine shell and a screw propeller positioned in the molding machine shell, and two ends of the screw propeller are respectively connected into a molding machine driving shaft and an extrusion die.

Preferably, the pre-carbonization furnace comprises a pre-carbonization chamber and a pre-carbonization temperature control chamber arranged on the pre-carbonization chamber; a pre-carbonization burner and a pre-carbonization air inlet pipe are arranged below the pre-carbonization chamber, and the pre-carbonization burner and the pre-carbonization air inlet pipe are symmetrically arranged; the pre-carbonization device is characterized in that a pre-carbonization exhaust pipe is arranged above the pre-carbonization chamber, a pre-carbonization discharge pipe is arranged below the pre-carbonization burner, and a pre-carbonization discharge gate plate is arranged on the pre-carbonization discharge pipe.

Preferably, the carbonization furnace comprises a carbonization chamber and a carbonization temperature control chamber arranged on the carbonization chamber; a carbonization burner and a carbonization air inlet pipe are arranged below the carbonization chamber, and the carbonization burner and the carbonization air inlet pipe are symmetrically arranged; and a carbonization exhaust pipe is arranged above the carbonization chamber, a carbonization discharge pipe is arranged below the carbonization combustor, and a carbonization discharge gate plate is arranged on the carbonization discharge pipe.

Preferably, the calciner comprises a calciner chamber and flaps located inside the calciner chamber; the calcining chamber is provided with a calcining temperature control chamber and a calcining air inlet pipe respectively, a calcining exhaust pipe is arranged above the calcining chamber, a calcining burner and a calcining discharge pipe are arranged below the calcining chamber, and the calcining burner is positioned between the calcining chamber and the calcining discharge pipe.

Preferably, the cooler comprises a cooler shell and a cooling rotary disc positioned inside the cooler shell, and stirring blades are arranged on the cooling rotary disc; one end of the cooler shell is provided with a cooler driving shaft, and the other end of the cooler shell is provided with a cold air inlet pipe and a combustion-supporting gas injection pipe; the cooler driving shaft is connected with the cooling rotary disc, and the cold air inlet pipe is communicated with the cooling rotary disc.

The invention provides a method for preparing biomass fuel by using crop straws, which comprises the following steps:

putting crop straws into a crusher so that the crusher crushes the crop straws to a length less than or equal to 3cm to obtain straw crushed materials;

conveying the crushed straw into a dryer through a feeder connected with the crusher so that the dryer dries the crushed straw to a water content of 6-12%;

extruding the dried crushed straw materials into block-shaped materials by an extrusion forming machine;

lifting the block materials to a pre-carbonization furnace through a lifter so as to carry out pre-carbonization treatment on the block materials under the conditions that the temperature is 200-270 ℃ and the pre-carbonization time is 3.5 h;

conveying the pre-carbonized block material to a carbonization furnace to perform carbonization treatment on the block material at the temperature of 270-390 ℃ for 2 h;

conveying the block materials after carbonization treatment to a calcining furnace, so that the block materials are calcined at the temperature of 390-;

conveying the calcined blocky materials to a cooler for cooling treatment to form biomass fuel;

and conveying the cooled biomass fuel to a packaging machine through a conveyor for packaging.

The technical scheme provided by the embodiment of the invention can have the following beneficial effects:

the invention provides equipment and a method for preparing biomass fuel by utilizing crop straws. The method adopts the process of raw material → pulverization → drying → molding → carbonization → cooling → packaging to prepare the biomass fuel. In the process of preparing the biomass fuel, the crop straws are subjected to pre-carbonization, carbonization and calcination treatment with reasonable control of temperature and time, and the formed biomass fuel is not easy to break and crack. The biomass fuel prepared by the equipment and the method has the advantages of small volume, convenient storage and transportation, cleanness and sanitation, and lower sulfur content and ash content than pulverized coal, can be directly used for civil and industrial fuel boilers, can be supplied to industrial production, rural greenhouses, poultry houses, vegetable greenhouses, drying chambers and the like, and can also be applied to industries such as metallurgy, chemical industry, environmental protection, electric power and the like.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.

Drawings

In order to more clearly explain the technical solution of the present application, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious to those skilled in the art that other drawings can be obtained according to the drawings without any creative effort.

FIG. 1 is a schematic structural diagram of an apparatus for preparing biomass fuel from crop straws according to an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of a pulverizer provided by an embodiment of the present invention;

FIG. 3 is a schematic diagram of a feeder according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of a dryer provided in an embodiment of the present invention;

FIG. 5 is a schematic structural diagram of an extrusion molding machine according to an embodiment of the present invention;

FIG. 6 is a schematic structural diagram of a carbonization device provided in an embodiment of the present invention;

FIG. 7 is a schematic flow chart of a method for preparing biomass fuel by using crop straws according to an embodiment of the invention;

the symbols represent:

1-pulverizer, 101-pulverizer housing, 102-pulverizing chamber, 103-pulverizer rotating shaft, 104-annular screen, 105-hammer sheet, 106-toothed plate, 107-pulverizing chamber inlet, 108-pulverizing chamber outlet;

2-feeder, 201-feeder housing, 202-spiral, 203-spiral feeder motor, 204-feeder inlet, 205-feeder outlet, 206-spiral blade;

3-dryer, 301-dryer shell, 302-steam inlet pipe, 303-steam outlet pipe, 304-rotating disc shaft, 305-disc, 306-scraper, 307-dryer drive motor, 308-dryer outlet, 309-steam regulating valve, 310-moisture detector;

4-extrusion molding machine, 401-molding machine shell, 402-screw propeller, 403-molding machine driving shaft, 404-extrusion die and 405-molding machine driving motor;

5-an elevator, 6-a carbonization device, 7-a conveyor and 8-a packaging machine;

61-a pre-carbonization furnace, 6101-a pre-carbonization chamber, 6102-a pre-carbonization temperature control chamber, 6103-a pre-carbonization burner, 6104-a pre-carbonization air inlet pipe, 6105-a pre-carbonization exhaust pipe, 6106-a pre-carbonization discharge pipe and 6107-a pre-carbonization discharge gate plate;

62-carbonization furnace, 6201-carbonization chamber, 6202-carbonization temperature control chamber, 6203-carbonization burner, 6204-carbonization air inlet pipe, 6205-carbonization exhaust pipe, 6206-carbonization discharge pipe, 6207-carbonization discharge gate;

63-calcining furnace, 6301-calcining chamber, 6302-folded plate, 6303-calcining temperature control chamber, 6304-calcining air inlet pipe, 6305-calcining exhaust pipe, 6306-calcining burner and 6307-calcining discharge pipe;

64-cooler, 6401-cooler shell, 6402-cooling rotating disk, 6403-stirring blade, 6404-cooler driving shaft, 6405-cold air inlet pipe and 6406-combustion-supporting gas injection pipe.

Detailed Description

Referring to fig. 1, fig. 1 shows a schematic structural diagram of an apparatus for preparing biomass fuel by using crop straws according to an embodiment of the present application. As can be seen from fig. 1, the apparatus for preparing biomass fuel by using crop straws provided by the embodiment of the present application includes a pulverizer 1, a feeder 2, a dryer 3, an extrusion molding machine 4, a lifter 5, a carbonization device 6, a conveyor 7 and a packaging machine 8, and the above components are connected in sequence according to the inlet and outlet sequence of crop straws. The structure, connection, operation, and the like of the respective members of the pulverizer 1 and the like will be described in detail below.

Referring to fig. 2, fig. 2 shows a schematic structural diagram of a pulverizer in an embodiment of the present application. As shown in fig. 2, the pulverizer 1 is a component for pulverizing crop straws, and the pulverizer 1 in the embodiment of the present application is a hammer mill. Specifically, the pulverizer 1 includes a pulverizer housing 101 and a pulverizing chamber 102 located inside the pulverizer housing 101. The top of the shredder housing 101 is provided with a shredder chamber inlet 107. the shredder chamber inlet 107 is used for crop straw to enter the shredder chamber 102 and then be shredded in the shredder chamber 102. The bottom of the shredder housing 101 is also provided with a shredder chamber outlet 108. the shredder chamber outlet 108 is used for discharging shredded crop straw into the feeder 2. A crusher rotating shaft 103 and an annular screen 104 are arranged in the crushing chamber 102, and a hammer 105 is arranged outside the crusher rotating shaft 103. The crusher rotating shaft 103 is driven by the motor to rotate, and further drives the hammer blades 105 on the crusher rotating shaft 103 to rotate at a high speed. The crop straw entering the crushing chamber 102 is crushed to a certain extent by the striking action of the high-speed rotation of the hammer 105. The crusher rotor 103 is located in the centre of the circular screen 104 so that crushed crop straw can fall through the circular screen 104 to the bottom of the crusher housing 101 and then be discharged from the crushing chamber outlet 108 to the feeder 2.

In order to crush the crop straws to a greater extent, a toothed plate 10 is arranged on one side of the annular screen 104 facing the rotating shaft 103 of the crusher. Because the rotating shaft 103 of the crusher is located at the center of the circular screen cloth 104, and the hammer blades 105 can provide a certain centrifugal force to the crop straws under the high-speed rotation, the primarily crushed crop straws can be thrown to the toothed plate 106. The crop straw thrown to the toothed plate 106 is collided and rubbed on the toothed plate 106 and the annular screen 104, so that the crushed crop straw is further crushed, and the straw crushed material is obtained. Because the circular screen 104 has a certain aperture, the straw crushed material with a length greater than the aperture of the circular screen 104 can be crushed in the crushing chamber 102 until the straw crushed material can pass through the circular screen 104. More preferably, the aperture of the ring screen 104 is less than or equal to 3cm, i.e. the length of the straw shatter passing through the ring screen 104 is less than or equal to 3 cm.

Referring to fig. 3, fig. 3 shows a schematic structural view of a feeder in an embodiment of the present application. As can be seen from fig. 3, the feeder 2 comprises a feeder housing 201 and a spiral pipe 202 located inside the feeder housing 201. The feeder housing 201 is externally provided with a screw feeder motor 203, and the screw feeder motor 203 is connected to the screw pipe 202 by a driving shaft so that the screw pipe 202 is rotated by the screw feeder motor 203. The feeder housing 201 is provided with a feeder inlet 204 and a feeder outlet 205, wherein the feeder inlet 204 is located at one end close to the screw feeder motor 203, and the feeder outlet 205 is located at one end far away from the screw feeder motor 203. The spiral pipe 202 is provided with a spiral blade 206, and the spiral blade 206 can preliminarily reduce the volume of the crushed straw in the process of pushing the crushed straw to the outlet 205 of the feeder. In the present embodiment, the feeder 2 is arranged obliquely, and the feeder outlet 205 is located above the feeder inlet 204. More preferably, the angle of inclination of the feeder 2 is 30 °.

The screw feeder motor 203 is activated and the screw 202 rotates, which in turn rotates the screw blade 206. Straw fines enter the feeder housing 201 from the feeder inlet 204 and fall onto the helical blades 206. Because the feeder 2 is arranged obliquely, the crushed straw falling onto the helical blade 206 can be shrunk and accumulated on the helical blade 206 under the action of gravity, and the accumulation volume of the crushed straw is further reduced to a certain extent. The crushed straw is driven by the spiral rising of the spiral blade 206 to the feeder outlet 205, and then discharged into the dryer 3 through the feeder outlet 205.

Referring to fig. 4, fig. 4 is a schematic structural diagram of a dryer in an embodiment of the present application. As can be seen from fig. 4, the dryer 3 includes a dryer casing 301, and a steam inlet pipe 302 and a steam outlet pipe 303 provided on a surface of the dryer casing 301. The steam inlet pipe 302 is a pipe for hot steam to enter the dryer 3, and the steam outlet pipe 303 is a pipe for heat-exchanged steam to exit the dryer 3. A rotary disc shaft 304 is provided inside the dryer housing 301, and a hollow disc 305 is provided on the rotary disc shaft 304. A dryer driving motor 307 is provided outside the dryer housing 301, and the dryer driving motor 307 is connected to the rotary disk shaft 304 through a driving shaft. Thus, the rotary shaft 304 is rotated by the driving action of the dryer drive motor 307, and the hollow disc 305 is rotated. In the present embodiment, the rotating disc shaft 304 communicates with the disc 305, the steam inlet pipe 302, and the steam outlet pipe 303, respectively. Based on this, hot steam can enter the rotating disc shaft 304 through the steam inlet pipe 302 and further into the disc 305. Since the rotating disc shaft 304 and the disc 305 both have hot steam inside, the crushed straw discharged into the dryer 3 exchanges heat on the surfaces of the rotating disc shaft 304 and the disc 305, so that the crushed straw is dried by indirect heating of the hot steam. The crushed dried straw is discharged to the extrusion molding machine 4 through a dryer outlet 308 provided in the dryer housing 301. The heat-exchanged gas is discharged through the steam outlet pipe 303.

Further, since the ground straw has a high water content, it tends to adhere to the rotary shaft 304 and the disc 305 during drying in the dryer 3. Based on this, in the apparatus provided in the embodiment of the present application, the scraper 306 is further provided on the inner surface of the dryer housing 301. During the rotation of the rotating disc shaft 304 and the disc 305, the scraper 306 can scrape the straw pulverized material adhered thereon, so that more straw pulverized material is heated. Further, a steam adjusting valve 309 and a humidity detector 310 are further provided inside the dryer casing 301, wherein the steam adjusting valve 309 is provided on the steam inlet pipe 302, and the humidity detector 310 is provided at the dryer outlet 308. The amount of hot steam discharged into the rotating disk shaft 304 can be adjusted by the steam adjusting valve 309. The moisture content of the straw pulverized material can be detected through the moisture detector 310, and then it is determined whether the straw pulverized material is discharged. When the moisture detector 310 detects that the moisture content of the crushed straw does not meet the standard requirement, the steam regulating valve 309 increases the content of hot steam discharged into the rotating disc shaft 304; when the moisture detector 310 detects that the moisture content of the crushed straw meets the standard requirement, the steam regulating valve 309 reduces the content of hot steam discharged into the rotating disc shaft 304, so that the maximum utilization of the hot steam is realized. Preferably, the water content of the straw crushed material is controlled to be 6-12%.

Referring to fig. 5, fig. 5 is a schematic structural view of an extrusion molding machine according to an embodiment of the present invention. As can be seen from fig. 5, the extrusion molding machine 4 includes a molding machine housing 401 and a screw pusher 402 located inside the molding machine housing 401. The outlet 308 of the dryer is a feeding port of the extrusion molding machine 4. Both ends of the screw pusher 402 are connected to a molding machine drive shaft 403 and an extrusion die 404, respectively, and the molding machine drive shaft 403 is connected to a molding machine drive motor 405 provided outside the molding machine housing 401. When the molding machine driving motor 405 is started, the screw pusher 402 pushes the crushed straw toward the extrusion die 404 by the molding machine driving motor 405 under the action of the molding machine driving shaft 403, so that the crushed straw can enter the extrusion die 404. In the process of propelling the straw pulverized material, the stress applied to the straw pulverized material is gradually increased. When the straw shredder reaches the outlet of the extrusion die 404, the straw shredder is subjected to the greatest stress and is extruded into a block-shaped material.

Further, in order to increase the strength of the pressed block-shaped material, a binder is added at the outlet 308 of the dryer to increase the binding degree of the crushed straw. The adhesive in the embodiment of the application adopts humic acid-starch, and the mass ratio of the straw crushed materials to the adhesive is 97: 3. In the present embodiment, the extrusion die 404 has a hexagonal rod shape with an outer diameter of 50mm, an inner diameter of 10mm, and a length of 30 mm. Of course, the shape and size of the extrusion die 404 can be adjusted according to actual production conditions, and the application is not limited thereto.

The lifting machine 5 in the embodiment of the application adopts a conveyor belt mode for transmission. In order to save the space occupation of the whole equipment, the elevator 5 is obliquely arranged. More preferably, the inclination of the hoisting machine 5 is 30 °.

Referring to fig. 6, fig. 6 shows a schematic structural diagram of a carbonization device in an embodiment of the present application. As shown in fig. 6, the carbonization device 6 includes a pre-carbonization furnace 61, a carbonization furnace 62, a calcining furnace 63, and a cooler 64 connected in sequence, wherein the pre-carbonization furnace 61 is connected to the hoist 5, and the cooler 64 is connected to the conveyor 7. The pre-carbonization furnace 61 is a device for preliminarily carbonizing the block-shaped material formed by extruding the straw pulverized material. The carbonization furnace 62 is a device for carbonizing the preliminarily carbonized block-shaped material. The calciner 63 is a device for calcining the carbonized block-shaped material. The cooler 64 is a device for cooling the calcined block material. The pre-carbonization furnace 61, the carbonization furnace 62, the calcining furnace 63, and the cooler 64 will be described in detail below, respectively.

The pre-carbonization furnace 61 includes a pre-carbonization chamber 6101 and a pre-carbonization temperature control chamber 6102 provided in the pre-carbonization chamber 6101. Wherein, the pre-carbonization chamber 6101 is used for pre-carbonization treatment of the bulk material, and the pre-carbonization temperature control chamber 6102 is used for monitoring the temperature in the pre-carbonization chamber 6101. A pre-carbonization burner 6103 and a pre-carbonization air inlet pipe 6104 are arranged below the pre-carbonization chamber 6101, and the pre-carbonization burner 6103 and the pre-carbonization air inlet pipe 6104 are symmetrically arranged. The pre-carbonization burner 6103 can provide heat energy into the pre-carbonization chamber 6101 under the influence of natural gas. The pre-carbonization air inlet pipe 6104 can provide air into the pre-carbonization chamber 6101, thereby providing combustion assistance to the pre-carbonization burner 6103. A pre-carbonization exhaust pipe 6105 is arranged above the pre-carbonization chamber 6101, so that the tail gas generated during the carbonization treatment in the pre-carbonization chamber 6101 is exhausted through the pre-carbonization exhaust pipe 6105. A pre-carbonization discharge pipe 6106 is arranged below the pre-carbonization burner 6103, and a pre-carbonization discharge gate 6107 is further arranged on the pre-carbonization discharge pipe 6106. When the block-shaped material is in the pre-carbonization process, the pre-carbonization discharge gate 6107 is in a closed state to prevent the block-shaped material from leaking out of the pre-carbonization discharge pipe 6106. After the pre-carbonization treatment of the block-shaped material is completed, the pre-carbonization discharge gate 6107 is opened, and the block-shaped material is discharged into the carbonization furnace 62 through the pre-carbonization discharge pipe 6106. In the embodiment of the present application, the temperature in the pre-carbonization chamber 6101 is controlled at 200 ℃ and 270 ℃, and the pre-carbonization time is 3.5 h.

The temperature in the pre-carbonization chamber 6101 is high, so that the block material after the pre-carbonization treatment has a high temperature. Based on this, the casing, the pre-carbonization discharge pipe 6106, and the pre-carbonization discharge gate 6107 of the pre-carbonization chamber 6101 in the embodiment of the present application are all made of a low-alloy carbon steel lining refractory plate, wherein the thickness of the low-alloy carbon steel is 8mm, and the thickness of the lining refractory plate is 16 mm.

The carbonization furnace 62 includes a carbonization chamber 6201, and a carbonization temperature control chamber 6202 provided on the carbonization chamber 6201. Wherein the carbonization chamber 6201 is used for carbonizing the bulk material, and the carbonization temperature control chamber 6202 is used for monitoring the temperature in the carbonization chamber 6201. A carbonization burner 6203 and a carbonization air inlet pipe 6204 are arranged below the carbonization chamber 6201, and the carbonization burner 6203 and the carbonization air inlet pipe 6204 are symmetrically arranged. The char burner 6203, under the influence of natural gas, is capable of providing thermal energy into the char chamber 6201. The charring air inlet tube 6204 can provide air into the charring chamber 6201 to provide combustion assistance to the charring burner 6203. A carbonization exhaust pipe 6205 is arranged above the carbonization chamber 6201, so that tail gas generated in the carbonization treatment in the carbonization chamber 6201 can be conveniently discharged through the carbonization exhaust pipe 6205. A carbonization discharging pipe 6206 is arranged below the carbonization combustor 6203, and a carbonization discharging flashboard 6207 is also arranged on the carbonization discharging pipe 6206. When the block-shaped material is in the carbonization process, the carbonization discharge gate 6207 is in a closed state to prevent the block-shaped material from leaking out of the carbonization discharge pipe 6206. After the carbonization treatment of the block-shaped material is completed, the carbonization discharging gate 6207 is opened, and the block-shaped material is discharged into the calcining furnace 63 through the carbonization discharging pipe 6206. In the embodiment of the application, the temperature in the carbonization chamber 6201 is controlled to be 270-390 ℃, and the carbonization time is 2 h.

The temperature in the carbonization chamber 6201 is higher, so that the block-shaped materials after carbonization treatment have higher temperature. Based on this, the shell, the carbonization discharge pipe 6206 and the carbonization discharge gate 6207 of the carbonization chamber 6201 in the embodiment of the application are all made of low-alloy carbon steel lining refractory plates, wherein the thickness of the low-alloy carbon steel is 8mm, and the thickness of the lining refractory plates is 18 mm.

The calcining furnace 63 includes a calcining chamber 6301 and a flap 6302 located inside the calcining chamber 6301. The calcining chamber 6301 is used to calcine the carbonized block material. The flaps 6302 inside the calcination chamber 6301 can increase the contact area of the lump materials with the natural gas in the calcination chamber 6301. A calcining temperature control chamber 6303 is provided in the calcining chamber 6301, and the calcining temperature control chamber 6303 is used to monitor the temperature in the calcining chamber 6301. A calcining burner 6306 and a calcining discharge pipe 6307 are provided below the calcining chamber 6301, and the calcining burner 6306 is located between the calcining chamber 6301 and the calcining discharge pipe 6307. The calciner burner 6306 is capable of providing heat energy to the calciner 6301 under the influence of natural gas. The calcining discharge pipe 6307 is used to discharge the calcined massive material out of the calcining chamber 6301. The calcining chamber 6301 is further provided with a calcining air inlet pipe 6304, and the calcining air inlet pipe 6304 can supply air into the calcining chamber 6301 to supply combustion assisting power to the calcining burner 6306. A calcining exhaust pipe 6305 is provided above the calcining chamber 6301, so that an exhaust gas calcining exhaust pipe 6305 generated during the calcining treatment in the calcining chamber 6301 is exhausted.

In the embodiment of the present application, the temperature in the calcination chamber 6301 is controlled to be 390-. In the process of calcining the block-shaped material in the calcining furnace 63, the interior of the block-shaped material changes to form a porous medium, and at this time, the specific surface area of the block-shaped material increases. In addition, various impurities remained in the block materials can be removed in the calcining process, and the carbon content of the block materials is improved.

The temperature in the calcination chamber 6301 is high, so that the lump material after calcination has a high temperature. Based on this, the calcining chamber 6301 and the calcining discharge pipe 6307 in the examples of the present application were each prepared using a low-alloy carbon steel-lined refractory plate, wherein the low-alloy carbon steel had a thickness of 10mm and the lined refractory plate had a thickness of 20 mm.

The calcining furnace 63 feeds the calcined lump materials to the cooler 64 through the calcining discharge pipe 6307 to be cooled. In the present embodiment, the cooler 64 includes a cooler housing 6401 and a cooling rotary disk 6402 located inside the cooler housing 6401, and the cooling rotary disk 6402 is connected to a cooler drive shaft 6404 provided at one end of the cooler housing 6401. Thus, the cooler drive shaft 6404 is rotated by the drive of the drive motor, and the cooling rotary disk 6402 connected to the cooler drive shaft 6404 is rotated. The cooling rotating disk 6402 is provided with stirring blades 6403, so that the cooling rotating disk 6402 rotates to drive the stirring blades 6403 to rotate, thereby stirring the block-shaped material in the cooler housing 6401.

In addition, the other end of the cooler shell 6401 is provided with a cold air inlet pipe 6405 and a combustion-supporting gas injection pipe 6406, wherein the cold air inlet pipe 6405 is communicated with the cooling rotary disc 6402, and the combustion-supporting gas injection pipe 6406 is communicated with the inside of the cooler shell 6401. Cold air can enter the cooling rotating disc 6402 through the cold air inlet pipe 6405, and then heat exchange is carried out on the blocky materials on the cooling rotating disc 6402, so that the blocky materials are cooled to normal temperature, and the biomass fuel is obtained. The oxidant can be injected onto the biomass fuel inside the cooler housing 6401 through the oxidant gas injection pipe 6406 so that the oxidant is attached to the surface of the biomass fuel. The biomass fuel with the attached combustion improver can have better combustibility in use. In the embodiment of the application, the combustion improver is a mixture of waste engine oil and waste diesel oil, wherein the mass ratio of the waste engine oil to the waste diesel oil is 1: 5. The addition ratio of the combustion improver is 50g/m when in use³。

The biomass fuel formed after cooling by the cooler 64 is conveyed to the packaging machine 8 through the conveyor 7 for packaging. In the present embodiment, the conveyor 7 employs a horizontal conveyor belt to achieve horizontal conveyance of the biomass fuel.

Referring to fig. 7, an embodiment of the present application provides a method for preparing biomass fuel from crop straws, including:

s01: putting the crop straws into a crusher so that the crusher crushes the crop straws to a length less than or equal to 3cm to obtain straw crushed materials.

Crop straw is placed into the crushing chamber 102 through the crushing chamber inlet 107. The crusher rotating shaft 103 is driven by the motor to rotate, and further drives the hammer blades 105 on the crusher rotating shaft 103 to rotate at a high speed. The crop straw entering the crushing chamber 102 is crushed to a certain extent by the striking action of the high-speed rotation of the hammer 105. The crop straw after the preliminary crushing can be thrown to the toothed plate 106. The crop straw thrown to the toothed plate 106 is collided and rubbed on the toothed plate 106 and the annular screen 104, so that the crushed crop straw is further crushed, and the straw crushed material is obtained. The straw shredder falls through the ring screen 104 to the bottom of the shredder housing 101 and is then discharged from the shredder chamber outlet 108 to the feeder 2.

S02: and conveying the crushed straw into a dryer through a feeder connected with the crusher so that the dryer dries the crushed straw to a moisture content of 6-12%.

The screw feeder motor 203 is activated and the screw 202 rotates, which in turn rotates the screw blade 206. Straw fines enter the feeder housing 201 from the feeder inlet 204 and fall onto the helical blades 206. Because the feeder 2 is arranged obliquely, the crushed straw falling onto the helical blade 206 can be shrunk and accumulated on the helical blade 206 under the action of gravity, and the accumulation volume of the crushed straw is further reduced to a certain extent. The crushed straw is driven by the spiral rising of the spiral blade 206 to the feeder outlet 205, and then discharged into the dryer 3 through the feeder outlet 205.

The rotating disc shaft 304 is rotated by the driving action of the dryer driving motor 307, and the hollow disc 305 is rotated. Since the rotating disc shaft 304 and the disc 305 both have hot steam inside, the crushed straw discharged into the dryer 3 exchanges heat on the surfaces of the rotating disc shaft 304 and the disc 305, so that the crushed straw is dried by indirect heating of the hot steam. During the drying process of the crushed straw, the humidity of the crushed straw is adjusted and controlled through the steam adjusting valve 309 and the humidity detector 310, so that the water content of the crushed straw is controlled to be 6-12% when the crushed straw is discharged. The crushed dried straw is discharged to the extrusion molding machine 4 through a dryer outlet 308 provided in the dryer housing 301.

S03: and extruding the dried crushed straw materials into blocky materials by an extrusion forming machine.

Adhesive is added to the molding machine housing 401 through the dryer outlet 308. The molding machine driving motor 405 is started, and the screw pusher 402 pushes the crushed straw toward the extrusion die 404 by the molding machine driving motor 405 under the action of the molding machine driving shaft 403, so that the crushed straw can enter the extrusion die 404. In the process of propelling the straw pulverized material, the stress applied to the straw pulverized material is gradually increased. When the straw shredder reaches the outlet of the extrusion die 404, the straw shredder is subjected to the greatest stress and is extruded into a block-shaped material.

S04: and lifting the block materials to a pre-carbonization furnace through a lifter so as to carry out pre-carbonization treatment on the block materials under the conditions that the temperature is 200-270 ℃ and the pre-carbonization time is 3.5 h.

The lump materials are lifted into the pre-carbonization furnace 61 by the lifter 5. The pre-carbonization burner 6103 can provide heat energy into the pre-carbonization chamber 6101 under the influence of natural gas. The pre-charring air inlet pipe 6104 provides air into the pre-charring chamber 6101, and further provides combustion assisting power for the pre-charring burner 6103, thereby realizing the pre-charring treatment of the block material under the conditions that the temperature is 200-. The tail gas generated during the carbonization treatment in the pre-carbonization chamber 6101 is discharged through the pre-carbonization gas discharge pipe 6105. When the block-shaped material is in the pre-carbonization process, the pre-carbonization discharge gate 6107 is in a closed state to prevent the block-shaped material from leaking out of the pre-carbonization discharge pipe 6106. After the pre-carbonization treatment of the block-shaped material is completed, the pre-carbonization discharge gate 6107 is opened, and the block-shaped material is discharged into the carbonization furnace 62 through the pre-carbonization discharge pipe 6106.

S05: and conveying the pre-carbonized block material to a carbonization furnace to perform carbonization treatment on the block material at the temperature of 270-390 ℃ for 2 h.

The char burner 6203, under the influence of natural gas, is capable of providing thermal energy into the char chamber 6201. The carbonization air inlet pipe 6204 can provide air for the carbonization chamber 6201, so as to provide combustion assisting power for the carbonization burner 6203, thereby realizing carbonization treatment of the block-shaped materials under the conditions that the temperature is 270-390 ℃ and the carbonization time is 2 h. The tail gas generated during the carbonization treatment in the carbonization chamber 6201 is discharged through a carbonization exhaust pipe 6205. When the block-shaped material is in the carbonization process, the carbonization discharge gate 6207 is in a closed state to prevent the block-shaped material from leaking out of the carbonization discharge pipe 6206. After the carbonization treatment of the block-shaped material is completed, the carbonization discharging gate 6207 is opened, and the block-shaped material is discharged into the calcining furnace 63 through the carbonization discharging pipe 6206.

S06: and conveying the block materials after carbonization treatment to a calcining furnace, so that the block materials are calcined at the temperature of 390-500 ℃ for 4 h.

The calciner burner 6306 is capable of providing heat energy to the calciner 6301 under the influence of natural gas. The calcining air inlet pipe 6304 can provide air for the calcining chamber 6301, and further provide combustion assisting power for the calcining burner 6306, thereby realizing the calcining treatment of the block-shaped material at 390-500 ℃ for 4 h. The exhaust gas duct 6305 is used to exhaust the exhaust gas generated during the calcination process in the calcination chamber 6301. The calcined lump material is discharged into the cooler 64 through the calcination discharge pipe 6307. The tail gas discharged from the pre-carbonization chamber 6101, the carbonization chamber 6201 and the calcining chamber 6301 is collected and then treated in a centralized way.

S07: and conveying the calcined blocky material to a cooler for cooling treatment to form the biomass fuel.

The calcined lump material is discharged into the cooler 64 through the calcination discharge pipe 6307. The cooler drive shaft 6404 is rotated by the drive of the drive motor, and thereby the cooling rotary disk 6402 connected to the cooler drive shaft 6404 and the stirring blades 6403 provided on the cooling rotary disk 6402 are rotated. Cold air enters the cooling rotary disc 6402 through the cold air inlet pipe 6405, and then heat exchange is carried out on the blocky materials on the cooling rotary disc 6402, so that the blocky materials are cooled to normal temperature, and the biomass fuel is obtained.

S08: and conveying the cooled biomass fuel to a packaging machine through a conveyor for packaging.

The biomass fuel formed after cooling by the cooler 64 is conveyed to the packaging machine 8 through the conveyor 7 for packaging.

In the device and the method for preparing the biomass fuel by using the crop straws, provided by the embodiment of the application, the biomass fuel is prepared by adopting a process and corresponding equipment of raw material → crushing → drying → molding → carbonization → cooling → packaging. In the process of preparing the biomass fuel, the crop straws are subjected to pre-carbonization, carbonization and calcination treatment with reasonable control of temperature and time, and the formed biomass fuel is not easy to break and crack. The biomass fuel prepared by the equipment and the method provided by the embodiment of the application has the advantages of small volume, convenience in storage and transportation, cleanness and sanitation, and lower sulfur content and ash content than pulverized coal, can be directly used for civil and industrial fuel boilers, is supplied to industrial production and rural greenhouses, poultry houses, vegetable greenhouses, drying rooms and the like, and can also be applied to industries such as metallurgy, chemical industry, environmental protection, electric power and the like.

Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure herein. This application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.

It is to be understood that relational terms such as "first" and "second," and the like, may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. The invention is not limited to the precise arrangements described above and shown in the drawings, and various modifications and changes may be made without departing from the scope thereof. The scope of the invention is limited only by the appended claims.

Claims (10)

1. An apparatus for preparing biomass fuel by using crop straws is characterized by comprising: the crop straw drying and carbonizing machine comprises a crusher (1), a feeder (2), a dryer (3), an extrusion molding machine (4), a lifter (5), a carbonizing device (6), a conveyor (7) and a packing machine (8) which are sequentially connected according to the inlet and outlet sequence of crop straws; the carbonization device (6) comprises a pre-carbonization furnace (61), a carbonization furnace (62), a calcining furnace (63) and a cooler (64) which are sequentially connected, the pre-carbonization furnace (61) is connected with the lifting machine (5), and the cooler (64) is connected with the conveyor (7).

2. The apparatus according to claim 1, characterized in that the pulverizer (1) comprises a pulverizer housing (101) and a pulverizing chamber (102) located inside the pulverizer housing (101); a pulverizer rotating shaft (103) and an annular screen (104) are arranged in the pulverizing chamber (102), and the pulverizer rotating shaft (103) is positioned in the center of the annular screen (104); the outer side of the crusher rotating shaft (103) is provided with a hammer sheet (105), and one side of the annular screen (104) facing the crusher rotating shaft (103) is provided with a toothed plate (106).

3. The apparatus according to claim 1, characterized in that the dryer (3) comprises a dryer housing (301) and a steam inlet pipe (302) and a steam outlet pipe (303) arranged at the surface of the dryer housing (301); a rotary disc shaft (304) is arranged in the dryer shell (301), and a hollow disc (305) is arranged on the rotary disc shaft (304); the rotating disc shaft (304) is communicated with the disc (305), the steam inlet pipe (302) and the steam outlet pipe (303) respectively.

4. The apparatus according to claim 3, characterized in that the inner surface of the dryer housing (301) is further provided with scrapers (306).

5. The apparatus according to claim 1, wherein the extrusion molding machine (4) comprises a molding machine housing (401) and a screw pusher (402) located inside the molding machine housing (401), both ends of the screw pusher (402) being connected to a molding machine drive shaft (403) and an extrusion die (404), respectively.

6. The apparatus according to claim 1, wherein the pre-carbonization furnace (61) comprises a pre-carbonization chamber (6101) and a pre-carbonization temperature control chamber (6102) provided on the pre-carbonization chamber (6101); a pre-carbonization burner (6103) and a pre-carbonization air inlet pipe (6104) are arranged below the pre-carbonization chamber (6101), and the pre-carbonization burner (6103) and the pre-carbonization air inlet pipe (6104) are symmetrically arranged; a pre-carbonization exhaust pipe (6105) is arranged above the pre-carbonization chamber (6101), a pre-carbonization discharge pipe (6106) is arranged below the pre-carbonization burner (6103), and a pre-carbonization discharge gate plate (6107) is arranged on the pre-carbonization discharge pipe (6106).

7. The apparatus of claim 1, wherein the carbonization furnace (62) comprises a carbonization chamber (6201) and a carbonization temperature control chamber (6202) disposed on the carbonization chamber (6201); a carbonization burner (6203) and a carbonization air inlet pipe (6204) are arranged below the carbonization chamber (6201), and the carbonization burner (6203) and the carbonization air inlet pipe (6204) are symmetrically arranged; and a carbonization exhaust pipe (6205) is arranged above the carbonization chamber (6201), a carbonization discharge pipe (6206) is arranged below the carbonization combustor (6203), and a carbonization discharge gate plate (6207) is arranged on the carbonization discharge pipe (6206).

8. The plant according to claim 1, characterized in that the calciner (63) comprises a calciner (6301) and flaps (6302) located inside the calciner (6301); calcining temperature control room (6303) and calcining air inlet pipe (6304) are respectively arranged on calcining chamber (6301), calcining exhaust pipe (6305) is arranged above calcining chamber (6301), calcining burner (6306) and calcining discharge pipe (6307) are arranged below calcining chamber (6301), and calcining burner (6306) is located between calcining chamber (6301) and calcining discharge pipe (6307).

9. The apparatus according to claim 1, characterized in that the cooler (64) comprises a cooler housing (6401) and a cooling rotating disc (6402) inside the cooler housing (6401), the cooling rotating disc (6402) being provided with stirring blades (6403); a cooler driving shaft (6404) is arranged at one end of the cooler shell (6401), and a cold air inlet pipe (6405) and a combustion-supporting gas injection pipe (6406) are arranged at the other end of the cooler shell; the cooler driving shaft (6404) is connected with the cooling rotary disc (6402), and the cold air inlet pipe (6405) is communicated with the cooling rotary disc (6402).

10. A method for preparing biomass fuel by utilizing crop straws is characterized by comprising the following steps:

putting crop straws into a crusher so that the crusher crushes the crop straws to a length less than or equal to 3cm to obtain straw crushed materials;

conveying the crushed straw into a dryer through a feeder connected with the crusher so that the dryer dries the crushed straw to a water content of 6-12%;

extruding the dried crushed straw materials into block-shaped materials by an extrusion forming machine;

lifting the block materials to a pre-carbonization furnace through a lifter so as to carry out pre-carbonization treatment on the block materials under the conditions that the temperature is 200-270 ℃ and the pre-carbonization time is 3.5 h;

conveying the pre-carbonized block material to a carbonization furnace to perform carbonization treatment on the block material at the temperature of 270-390 ℃ for 2 h;

conveying the block materials after carbonization treatment to a calcining furnace, so that the block materials are calcined at the temperature of 390-;

conveying the calcined blocky materials to a cooler for cooling treatment to form biomass fuel;

and conveying the cooled biomass fuel to a packaging machine through a conveyor for packaging.