CN115502169A

CN115502169A - Solid waste feeding system and feeding process

Info

Publication number: CN115502169A
Application number: CN202211131958.5A
Authority: CN
Inventors: 曹虎子; 贾昀澎; 顾潮冰; 赵博鸿
Original assignee: Shanghai Nuclear Energy Environmental Protection Technology Co ltd
Current assignee: Shanghai Nuclear Energy Environmental Protection Technology Co ltd
Priority date: 2022-09-16
Filing date: 2022-09-16
Publication date: 2022-12-23

Abstract

The invention discloses a solid waste feeding system and a feeding process. The solid waste feeding system comprises a pretreatment unit and a feeding unit, wherein the pretreatment unit is sequentially provided with a chopper, a mixer and an extrusion molding machine from top to bottom; the chopper is connected with the mixer in a skid-mounted manner through a first lock hopper, the mixer is connected with the extrusion molding machine in a skid-mounted manner through a second lock hopper, the first lock hopper and the second lock hopper are respectively provided with a first screen and a second screen, and the first screen and the second screen are used for vibrating and screening passing particles and then feeding the particles into downstream equipment; the feeding unit is sequentially provided with a conveyor, a feeding hopper and an unloader; the outlet of the extrusion molding machine is connected with the inlet of the conveyor, the outlet of the conveyor is connected with the feed inlet of the feed hopper, and the discharge outlet of the feed hopper is connected with the discharger; the feed hopper is provided with a shielding gas inlet. The system and method of the present invention can automatically control the feed rate of solid waste without causing a safety problem due to clogging.

Description

Solid waste feeding system and feeding process

Technical Field

The invention relates to a solid waste feeding system and a feeding process.

Background

With the development of society and industry, the energy demand is increased rapidly, the development of nuclear energy is also advanced rapidly, and the problem of volume reduction treatment of radioactive waste is in urgent need of solution. The fluidized bed steam reforming technology can effectively treat radioactive waste resin, dry miscellaneous solid waste, chemical waste liquid, waste oil and organic pollutant solvent (TPB). However, the solid waste may be clogged in a pipe during the feeding process, thereby causing a safety problem, and the solid waste may be oxidized, resulting in a defect that the efficiency of the solid waste is lowered in the subsequent reforming reaction.

Disclosure of Invention

The method aims to solve the problems that in the feeding process of the prior art, solid waste blocks a pipeline to cause safety problem, and the solid waste is oxidized to cause the efficiency of the solid waste to be reduced in the subsequent reforming reaction. To meet the feed requirements of steam reforming on inactive solid waste, the present invention provides a solid waste feed system and feed process. The system and the method can automatically control the feeding speed of the solid waste, and can not cause the safety problem due to blockage; in addition, the system and the method can provide solid waste particles with uniform size for the reforming furnace, thereby improving the reforming efficiency of the solid waste in the subsequent treatment process.

The present invention solves the above technical problems by the following technical solutions.

The present invention provides a solid waste feeding system, comprising a pre-treatment unit and a feeding unit,

the pretreatment unit is sequentially provided with a chopper, a mixer and an extrusion molding machine from top to bottom; the chopper is connected with the mixing machine in a skid-mounted manner through a first lock hopper, the mixing machine is connected with the extrusion forming machine in a skid-mounted manner through a second lock hopper, the first lock hopper and the second lock hopper are respectively provided with a first screen and a second screen, and the first screen and the second screen are used for vibrating and screening passing particles and then feeding the particles into downstream equipment;

the feeding unit is sequentially provided with a conveyor, a feeding hopper and a discharger; the outlet of the extrusion molding machine is connected with the inlet of the conveyor, the outlet of the conveyor is connected with the feed inlet of the feed hopper, and the discharge outlet of the feed hopper is connected with the discharger; the feeder hopper is provided with a shielding gas inlet.

In the invention, the skid-mounted type refers to an integration mode that the functional components are integrated on an integral base and can be integrally installed and moved.

In the present invention, preferably, the solid waste feeding system further comprises an electric block; the electric block is arranged at the top of the factory building and used for hoisting solid wastes to the chopper.

In the present invention, preferably, the shredder is provided with a shredding device for coarsely shredding the material to obtain a large-particle material.

In the invention, preferably, the first lock hopper is provided with a first screen; more preferably, the aperture of the first screen is 0.5 mm-2 mm.

In the present invention, preferably, the mixer is provided with a crushing device for finely crushing the material to obtain small-particle material.

In the invention, preferably, the second lock hopper is provided with a second screen; more preferably, the aperture of the second screen is 0.5 mm-2 mm.

Wherein, after the coarse chopping by the chopping device and the fine chopping by the crushing device, the particles obtained by mixing are more uniform.

Wherein, preferably, the aperture of the second screen is smaller than the aperture of the first screen.

In the invention, the extrusion molding machine adopts a granulation and feeding integrated design, and the crushed solid waste is extruded and granulated to form high-density particles which are sent to a steam reforming furnace.

In the invention, preferably, the extrusion molding machine is provided with a cooling circulation device to ensure that the material discharging temperature meets the requirement.

In the invention, preferably, the first lock hopper and the second lock hopper are both provided with a weighing scale, and more preferably, the weighing scales are piezoelectric crystal sensor weighing scales; the weighing scale can measure the weight of materials in the first lock hopper and the second lock hopper, and sends signals through the signal controller to control the rotating speed of the chopping device and the mixing device, so that the material blanking amount or the blanking speed is controlled, and the automatic raw material preparation is realized.

In the invention, an operation maintenance platform is preferably arranged below the extrusion molding machine.

In the invention, preferably, the conveyor is a spiral feeding conveyor for rotationally inputting materials into the feed hopper; the feed hopper serves for temporary storage.

In the invention, the discharger is preferably a star discharger which has better sealing performance and is convenient for conveying materials.

In a preferred embodiment, the feed hopper, the star discharger and the feed screw conveyor are used to jointly control the discharge rate.

In the present invention, preferably, the feed hopper includes a cylinder and a cone; the cylinder is located above the cone.

Preferably, the feed inlet is formed in the center of the top of the cylinder, and the discharge outlet is formed in the bottom of the cone.

Wherein, preferably, the top of cylinder is equipped with reserve mouth, level gauge mouth and drain.

Preferably, the cylinder is provided with a manhole, a thermometer port, an ear type support and a grounding plate; the ear type support is arranged on the upper portion of the outer wall of the cylinder, and the grounding plate is arranged in the middle of the cylinder.

Wherein, preferably, the outer wall of the cone is provided with a protective gas inlet; the protective gas inlet is connected with a gas supply device.

Wherein, preferably, the angle of the bottom opening of the cone is 60 ℃.

In the present invention, preferably, a protective cover is disposed outside each of the first lock bottom hopper and the second lock bottom hopper.

The present invention also provides a solid waste feeding process using the above solid waste feeding system, comprising the steps of:

s1: adding the solid waste into a pretreatment unit, and sequentially carrying out crushing, screening and extrusion forming treatment to obtain solid waste particles; the density of the solid waste particles is 1-2 kg/L;

s2: and introducing protective gas into the feed hopper, and adding the solid waste particles into the reactor sequentially through the conveyor, the feed hopper and the discharger.

In the invention, preferably, the solid waste is obtained by sorting; the purpose of the sorting is to remove metal pieces from the solid waste that are not conducive to cutting and pressing.

In the present invention, preferably, the solid waste includes one or more of rubber, cloth, plastic, paper and wood.

In step S1, preferably, the crushing and screening operations include first crushing and first screening, and second crushing and second screening in sequence.

Wherein, preferably, the first crushing is performed in the shredder.

Wherein, preferably, the first sieving is performed using the first sieve; the particles that pass through the first screen enter the mixer and the particles that do not pass through the first screen return to the chopper for continued chopping.

Wherein, preferably, the second crushing is performed in the mixer.

Wherein, preferably, the second sieving is performed using the second screen; and the particles passing through the second screen enter the extrusion molding machine, and the particles not passing through the second screen return to the mixer to be continuously crushed.

In step S1, preferably, the temperature of the solid waste particles is less than 120 ℃.

In step S1, preferably, the size of the solid waste particles is less than 20mm.

In step S2, preferably, the discharging speed of the discharger is less than 300kg/h.

In step S2, preferably, the pressure of the feeding hopper is normal pressure.

In step S2, preferably, the protective gas is nitrogen, the protective gas can fluidize the material to prevent blockage, and the protective gas can cool the solid waste, so as to prevent the surface of the solid waste from being oxidized, which results in a reduction in reforming efficiency.

In step S2, the particle size of the particles entering the reactor is preferably less than or equal to 7mm.

On the basis of the common knowledge in the field, the above preferred conditions can be combined randomly to obtain the preferred embodiments of the invention.

The reagents and starting materials used in the present invention are commercially available.

The positive progress effects of the invention are as follows:

1. in the solid waste feeding system, the skid-mounted design is adopted, so that the solid waste feeding system is convenient to replace and maintain, the structure of the pretreatment unit is compact, and the cost of transportation and related matched equipment and instruments is reduced.

2. Use the charge-in system of this application, carry out the two-stage breakage to solid waste, the first order is the preliminary shearing of mincer, and the second level is that the shearing of blender is smashed and the misce bene, could extrude target size from this, has promoted crushing efficiency and mixing efficiency, provides the even solid waste granule of size for the reformer.

3. The solid waste feed system of the present invention facilitates operation under negative pressure conditions to reduce dust pollution.

4. In the solid waste feeding process, the protective gas is introduced to fluidize the materials to prevent blockage, and the protective gas can cool solid waste particles, so that the surface oxidation of the solid waste particles is prevented, and the reduction of the reforming efficiency is avoided.

Drawings

Fig. 1 is a structural view of a solid waste feeding system of example 1.

Fig. 2 is a schematic structural diagram of a pretreatment unit of embodiment 1.

FIG. 3 is a structural view of a hopper in example 1.

Description of the reference numerals

A pretreatment unit A; a feed unit B;

a chopper 1; a shredding device 101;

a mixer 2; a crushing device 201;

an extrusion molding machine 3; a cooling circulation device 301;

a first lock hopper 4; a second lock hopper 5; a first screen 6; a second screen 7; a helical feed conveyor 8;

a feed hopper 9; DNAW feed port 901; DNAW discharge 902; a cylinder 903; a cone 904; a spare port 905; a level gauge port 906; a vent 907; a manhole 908; a thermometer port 909; an ear mount 910; a ground plate 911; a shielding gas inlet 912;

a discharger 10; an electric hoist 11; a protective cover 12; a gas supply device 13; a steam reformer 14.

Detailed Description

The invention is further illustrated by the following examples, which are not intended to limit the invention thereto. The experimental methods without specifying specific conditions in the following examples were selected according to the conventional methods and conditions, or according to the commercial instructions.

Example 1

Fig. 1 is a structural view of a solid waste feeding system of the present embodiment, which includes a pretreatment unit a and a feeding unit B.

Fig. 2 is a schematic structural diagram of the preprocessing unit a of the present embodiment. The pretreatment unit A is sequentially provided with a chopper 1, a mixer 2, an extrusion molding machine 3 and an electric hoist 11 from top to bottom. The electric block 11 is installed at the top of the factory building and is used for hoisting the solid waste to the chopper 1. The shredder 1 is provided with a shredding means 101 for coarse shredding of the material to obtain large particle material. The mixer 2 is provided with a crushing device 201 for finely chopping the material to obtain a small particle material. The chopper 1 is connected with the mixer 2 in a skid-mounted manner through a first lock hopper 4, the mixer 2 is connected with the extrusion molding machine 3 in a skid-mounted manner through a second lock hopper 5, the first lock hopper 4 and the second lock hopper 5 are respectively provided with a first screen 6 and a second screen 7, the first screen 6 and the second screen 7 are used for vibrating and screening passing particles and then feeding the particles into downstream equipment, and the aperture of the first screen 6 is 0.5-2 mm; the aperture of the second screen 7 is 0.5 mm-2 mm; the aperture of the second screen 7 is smaller than that of the first screen 6; after coarse chopping by the chopping device and fine chopping by the crushing device, the particles obtained by mixing are more uniform. The extrusion molding machine 3 adopts a granulation and feeding integrated design, and performs extrusion granulation on the crushed solid waste to form high-density particles which are sent to a steam reforming furnace 14. The extrusion molding machine 3 is provided with a cooling circulation device 301 to ensure that the material discharging temperature meets the requirements. First lock hopper 4 and second lock hopper 5 all are equipped with piezoelectric crystal sensor weigher, and the weight of material in this weigher measurable first lock hopper 4 and the second lock hopper 5, through the rotational speed of signal controller signals control comminution device 101 and mixing arrangement 201 to control material unloading volume or unloading speed, realize automatic raw materials preparation. An operation and maintenance platform is arranged below the extrusion molding machine 3. The exterior of each of the first lock hopper 4 and the second lock hopper 5 is provided with a protective cover 12.

The feeding unit B is sequentially provided with a spiral feeding conveyor 8, a feeding hopper 9 and a star-shaped discharger 10; the outlet of the extrusion molding machine 3 is connected with the inlet of the spiral feeding conveyor 8, the outlet of the spiral feeding conveyor 8 is connected with a DNAW feeding hole 901 at the top of the feeding hopper 9, and a DNAW discharging hole 902 at the bottom of the feeding hopper 9 is connected with a discharger 10; the screw feed conveyor 8 is used for rotary conveying the material into a feed hopper 9, the feed hopper 9 serving as a temporary storage. The star-shaped discharger 10 has better sealing performance and is convenient for conveying materials. A screw feed conveyor 8, a feed hopper 9 and a star discharger 10 are used to jointly control the discharge rate.

Fig. 3 is a structural view of the hopper 9 of the present embodiment. The feed hopper 9 comprises a cylinder 903 and a cone 904, the cylinder 903 being located above the cone 904. DNAW feed inlet 901 is arranged at the top center of cylinder 903, and DNAW discharge outlet 902 is arranged at the bottom of cone 904. The top of the feed hopper 9 is provided with a standby port 905, a level gauge port 906 and a vent port 907. The cylinder 903 is provided with a manhole 908, a thermometer port 909, an ear type support 910 and a grounding plate 911; the ear mount 910 is provided on the upper portion of the outer wall of the cylinder 903, and the ground plate 911 is provided in the middle of the cylinder 903. And a protective gas inlet 912 is arranged on the outer wall of the cone 904, and the protective gas inlet 912 is connected with the gas supply device 13. The opening angle at the bottom of cone 904 is 60 deg.c.

Example 2

This example is a solid waste feed process, the solid waste comprising one or more of rubber, cloth, plastic, paper, and wood; the solid waste feeding process used the solid waste feeding system of example 1, comprising the steps of:

s1: adding the sorted solid waste into a pretreatment unit A through an electric hoist 11, and sequentially carrying out primary crushing, primary screening, secondary crushing, secondary screening and extrusion forming treatment to obtain solid waste particles; the density of the solid waste particles is 1-2 kg/L, the temperature is less than 120 ℃, and the size is less than 20mm;

s2: introducing protective gas into a feed hopper 9, and adding solid waste particles into a reactor sequentially through a spiral feed conveyor 8, the feed hopper 9 and a discharger 10, wherein the particle size of the particles entering the reactor is less than or equal to 7mm; the discharging speed of the discharger 10 is less than 300kg/h, the pressure of the feed hopper 9 is normal pressure, and the protective gas is nitrogen.

Claims

1. A solid waste feeding system, characterized in that it comprises a pre-treatment unit and a feeding unit,

2. The solid waste feed system of claim 1, further comprising an electric hoist for hoisting the solid waste to the shredder;

and/or the chopper is provided with a chopping device for coarsely chopping the material;

and/or the first lock hopper is provided with a first screen;

and/or the mixer is provided with a crushing device for finely crushing the material;

and/or the second lock hopper is provided with a second screen;

and/or the extrusion forming machine is provided with a cooling circulation device;

and/or the first lock bottom hopper and the second lock bottom hopper are provided with weighing scales;

and/or protective covers are arranged outside the first lock hopper and the second lock hopper.

3. The solid waste feeding system of claim 2, wherein the first screen has a pore size of 0.5mm to 2mm;

and/or the aperture of the second screen is 0.5 mm-2 mm;

and/or the pore size of the second screen is smaller than the pore size of the first screen;

and/or the weighing scale is a piezoelectric crystal sensor weighing scale.

4. The solid waste feed system of claim 1, wherein the conveyor is a spiral feed conveyor for rotating material into the feed hopper;

and/or the discharger is a star discharger.

5. The solid waste feeding system of claim 1, wherein the feed hopper comprises a cylinder and a cone; the cylinder is located above the cone.

6. The solid waste feeding system of claim 5, wherein said feeding port is provided at the center of the top of said cylindrical body, and said discharging port is provided at the bottom of said conical body;

and/or a standby port, a level indicator port and a vent port are arranged at the top of the cylinder;

and/or the cylinder is provided with a manhole, a thermometer port, an ear type support, a grounding plate and a liquid level switch;

and/or a protective gas inlet is arranged on the outer wall of the cone; the protective gas inlet is connected with a gas supply device;

and/or the angle of the bottom opening of the cone is 60 ℃.

7. A solid waste feeding process, characterized in that it is carried out using a solid waste feeding system according to any one of claims 1 to 6, comprising the following steps:

8. The solid waste feeding process of claim 7, wherein in step S1, the solid waste comprises one or more of rubber, cloth, plastic, paper, and wood;

and/or the crushing and screening operations sequentially comprise primary crushing and primary screening, and secondary crushing and secondary screening;

and/or, the temperature of the solid waste particles is less than 120 ℃;

and/or the solid waste particles are less than 20mm in size.

9. The solid waste feeding process of claim 8, wherein in step S1, the first crushing is performed in the shredder;

and/or, performing the first sieving using the first screen;

and/or, the second crushing is carried out in the mixer;

and/or, performing the second sieving using the second screen.

10. The solid waste feeding process of claim 7, wherein in step S2, the discharging rate of said discharger is less than 300kg/h;

and/or the pressure of the feed hopper is normal pressure;

and/or the protective gas is nitrogen;

and/or the particle size of the particles entering the reactor is less than or equal to 7mm.