CN114873279A - Prevent to carry gaseous reverse biomass material feeding system of cluster of medium - Google Patents

Abstract

The invention discloses a biomass material feeding system for preventing conveying medium gas from reversely crossing, wherein an outlet at the bottom of a hopper is communicated with an inlet of a screw feeder, an outlet of the screw feeder is communicated with an inlet on the side surface of a blanking pipe, an outlet at the bottom of the blanking pipe is communicated with an inlet on the top of the side surface of a throat part of a Venturi tube, and a material conveying pipeline is communicated with the inlet of the Venturi tube; an output shaft of the variable frequency motor is connected with a driving shaft of the screw feeder, a gate plate door is arranged at an outlet at the bottom of the hopper, an observation window is arranged on the side surface of the hopper, and an end top cover plate is arranged at an opening at the top of the blanking pipe; the side of the blanking pipe is provided with a gas sealing device, wherein a sealing air pipeline is communicated with the gas sealing device, and a valve is arranged on the sealing air pipeline.

Description

A biomass material feeding system that prevents the reverse string of conveying medium gas

technical field

The invention belongs to the field of thermal power generation equipment, and relates to a biomass material feeding system for preventing reverse series of conveying medium gas.

Background technique

Biomass energy is a kind of renewable energy with huge reserves, wide distribution, high quality and clean (CO ₂ zero emission), and proper utilization of biomass energy will have a huge effect on CO ₂ emission reduction. Among them, biomass combustion power generation technology is environmentally friendly, Efficient and economical large-scale utilization technology has attracted more and more attention in the energy field at home and abroad. my country is rich in biomass resources. It is estimated that by 2050, the total biomass resources in my country will reach 1.4 billion tons of standard coal. Excluding the use of feed, fertilizers and industrial raw materials, there will be 890 million tons of standard coal biomass resources. for clean energy. As a renewable clean energy, the proportion of biomass in the energy structure is gradually increasing.

Biomass resources have the characteristics of large reserves, renewable, easy to store, and substitutable between different kinds of biomass. At present, in the vast rural areas of our country, most biomass is directly incinerated and returned to the fields, resulting in huge energy waste and environmental pollution. The biomass energy industry's centralized fuel treatment and environmental protection facilities can achieve the emission of flue gas and dust up to the standard. , to achieve the purpose of environmental protection. How to effectively utilize biomass resources has become a common concern.

China has the characteristics of primary energy distribution with more coal, less oil and lack of gas. Therefore, coal-fired thermal power units have always been the main force of power supply and the concentrated emission source of CO ₂ gas emissions. The technical route of coal has become one of the main technical ways to achieve the dual carbon goal. my country's biomass power generation industry originated from 20% biomass coupled power generation of 140MW units in Shiliquan Coal-fired Power Plant in Shandong Province in 2005. After 2006, it turned to a typical 30MW unit pure biomass fuel unit power generation project. It has developed to about 400 projects that have been put into production. Family.

In order to improve the absorption capacity of biomass, large-scale coal-fired power plants coupled with biomass power generation has become the mainstream technology of biomass centralized treatment. Biomass coupled power generation is a new type of renewable energy utilization. Appropriate technological transformation, with the help of the existing high-efficiency thermal power generation system and centralized pollutant control platform, supplements and consumes biomass resources that meet the requirements of agriculture, animal husbandry and land use, not only can guide the transformation and upgrading of traditional coal-fired power, but also enable renewable energy. Renewable energy is more friendly to meet the needs of the power system and reduce pollution emissions from open burning of agricultural and forestry waste residues. Biomass coupled power generation has the characteristics of high operating efficiency, good economic benefits, and low pollution emissions. It is an important measure to optimize the allocation of energy resources, promote the construction of ecological civilization, and promote green economic and social development.

In the process of coupling biomass of coal-fired units, biomass transportation is a very important link, and it is also the link with the most problems. Because biomass has the characteristics of low density, high water content, high fibrous tissue content, poor fluidity, and easy spontaneous combustion, problems such as reverse flow of the conveying medium gas, poor feeding and blockage, and spontaneous combustion are very likely to occur during the transportation process. In the process of coupling power generation of large-capacity coal-fired generator sets, how to safely, continuously, stably and accurately feed granular or powdered biomass materials into the pneumatic conveying pipeline of power station boilers is an urgent problem that needs to be solved. It is a very mature integrated solution, so it is necessary to develop a biomass feed system that prevents the reverse flow of the conveying medium gas to solve the above problems.

SUMMARY OF THE INVENTION

The purpose of the present invention is to overcome the above-mentioned shortcomings of the prior art, and to provide a biomass material feeding system that prevents the reverse flow of the conveying medium gas. into the power plant boiler pneumatic conveying pipeline.

In order to achieve the above purpose, the biomass material feeding system of the present invention for preventing the reverse string of the conveying medium gas includes a hopper, a screw feeder, a blanking pipe, a venturi pipe, a material conveying pipe, a frequency conversion motor and a sealed air pipe;

The bottom outlet of the hopper is communicated with the inlet of the screw feeder, the outlet of the screw feeder is communicated with the inlet on the side of the blanking tube, and the outlet at the bottom of the blanking tube is communicated with the top inlet on the side of the throat of the venturi tube. The conveying pipeline is communicated with the inlet of the venturi;

The output shaft of the frequency conversion motor is connected with the drive shaft of the screw feeder, a gate door is arranged at the bottom outlet of the hopper, an observation window is arranged on the side of the hopper, and an end top cover is arranged at the top opening of the blanking pipe;

A gas sealing device is arranged on the side of the blanking pipe, wherein the sealing air pipeline is communicated with the gas sealing device, and a valve is arranged on the sealing air pipeline.

The top cover plate and the blanking pipe are connected by threads, flanges or hinges.

A guide plate is set in the venturi tube.

The lower side of the hopper is a conical structure or a hyperbolic structure, and the upper side of the hopper is a cylindrical structure or a cuboid structure.

The end top cover plate is provided with an observation hole.

A scale indication is provided on the observation window.

A second temperature measuring point is arranged on the blanking tube, and the second temperature measuring point is located between the top cover plate and the gas sealing device.

A first temperature measuring point and a material level gauge are arranged in the hopper.

The side of the hopper is provided with a fire fighting device and a rapping device.

The present invention has the following beneficial effects:

During the specific operation of the biomass material feeding system for preventing the reverse flow of the conveying medium gas according to the present invention, a gate is provided at the bottom outlet of the hopper, and the gate can effectively isolate the hopper and the lower equipment. Safe maintenance, and prevent the bottom gas from entering the hopper. In addition, the accurate feeding of biomass materials is realized through the frequency conversion motor and the screw feeder; the medium gas in the material conveying pipeline is isolated by the gas sealing device to prevent the reverse string to the upstream of the material, and at the same time it can It has the effect of purging the material downstream, which makes the material conveying more smoothly and prevents the material from accumulating and blocking in the blanking pipe; the top opening of the blanking pipe is provided with an end top cover. When working, after the top cover is opened It can check the operation status in the blanking pipe, and can also be used as a clearing port when the blanking pipe is blocked. In addition, the venturi tube in the present invention utilizes the flowing gas in the material conveying pipe to generate negative pressure at the bottom of the blanking pipe, so that the blanking of the blanking pipe is smoother, and at the same time, it can effectively prevent the positive pressure in the material conveying pipe from bringing The air flow is reversed, so that the granular or powdered biomass material can be safely, continuously, stably and accurately sent to the pneumatic conveying pipeline of the power station boiler.

Description of drawings

FIG. 1 is a schematic structural diagram of the present invention.

Among them, 1 is the hopper, 2 is the observation window, 3 is the frequency conversion motor, 4 is the screw feeder, 5 is the top cover plate, 6 is the blanking pipe, 7 is the gas sealing device, 8 is the valve, and 9 is the sealing air Pipeline, 10 is the material conveying pipeline, 11 is the venturi tube, 12 is the guide plate, 13 is the gate door, 14 is the first temperature measuring point, 15 is the material level gauge, 16 is the rapping device, and 17 is the fire fighting device device.

Detailed ways

In order to make those skilled in the art better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only The embodiments are part of the present invention, not all of the embodiments, and are not intended to limit the scope of the present disclosure. Furthermore, in the following description, descriptions of well-known structures and techniques are omitted to avoid unnecessarily obscuring the concepts disclosed in the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

The accompanying drawings show a schematic structural diagram of an embodiment according to the disclosure of the present invention. The figures are not to scale, some details have been exaggerated for clarity, and some details may have been omitted. The shapes of various regions and layers shown in the figures and their relative sizes and positional relationships are only exemplary, and in practice, there may be deviations due to manufacturing tolerances or technical limitations, and those skilled in the art should Regions/layers with different shapes, sizes, relative positions can be additionally designed as desired.

Referring to FIG. 1 , the biomass material feeding system for preventing the reverse string of the conveying medium gas according to the present invention includes a hopper 1, a screw feeder 4, a blanking pipe 6, a venturi pipe 11, a material conveying pipe 10, a frequency conversion motor 3 and a seal air duct 9;

The bottom outlet of the hopper 1 is communicated with the inlet of the screw feeder 4, the outlet of the screw feeder 4 is communicated with the inlet on the side of the blanking pipe 6, and the outlet at the bottom of the blanking pipe 6 is connected with the side of the throat of the venturi tube 11. The top inlet is communicated, and the material conveying pipeline 10 is communicated with the inlet of the venturi tube 11;

The output shaft of the frequency conversion motor 3 is connected with the drive shaft of the screw feeder 4; the bottom outlet of the hopper 1 is provided with a gate door 13; the hopper 1 is provided with a first temperature measuring point 14 and a material level gauge 15; The side of the hopper 1 is provided with a fire fighting device 17 and a rapping device 16, the side of the hopper 1 is provided with an observation window 2, and the observation window 2 is provided with a scale indication; the top opening of the blanking pipe 6 is provided with an end top cover plate 5, The end top cover plate 5 is provided with an observation hole.

The side surface of the blanking pipe 6 is provided with a gas sealing device 7 , wherein the sealing air pipeline 9 communicates with the gas sealing device 7 , and a valve 8 is provided on the sealing air pipeline 9 .

The lower side of the hopper 1 is a conical structure or a hyperbolic structure, the upper side of the hopper 1 is a cylindrical structure or a cuboid structure, and the medium used by the fire fighting device 17 is gas or liquid.

The top cover plate 5 and the blanking pipe 6 are connected by threads, flanges or hinges. The blanking pipe 6 is provided with a second temperature measuring point, and the second temperature measuring point is located on the top cover plate 5 and the gas seal. between devices 7.

The gas source of the gas sealing device 7 is compressed air and compressed flue gas, and a material guide plate 12 is arranged in the venturi tube 11 .

The concrete working process of the present invention is:

The specific process of the start-up phase is as follows:

11) Check the entire system, confirm that the variable frequency motor 3, valve 8 and gate door 13 are in the closed state; confirm that the top cover 5 is in the closed state; the first temperature measuring point 14 and the second temperature measuring point are normal; the rapping device 16 Normal; the fire fighting device 17 is normal; confirm that the material conveying pipeline 10 is in operation;

12) Turn on the valve 8 in turn, turn on the frequency conversion motor 3, and open the gate door 13 between the hopper 1 and the screw feeder 4, and the hopper 1 starts to be loaded, and the interval between each operation is 1-5 minutes.

The specific process of the running phase is as follows:

21) Adjust the feeding amount of the system by adjusting the speed of the variable frequency motor 3;

22) Adjust the sealing effect of the gas sealing device 7 by adjusting the sealing air volume of the valve 8;

23) Check whether the blanking pipe 6 is blocked or the blanking is not smooth through the top cover plate 5;

24) Check the feeding situation of the hopper 1 on the spot through the observation window 2 and determine whether the warehouse is empty;

25) The material level is monitored remotely or locally through the material level meter 15, so as to determine the feeding time of the hopper 1;

26) Determine the sealing effect of the gas sealing device 7 by the second temperature measuring point on the blanking pipe 6 to prevent the reverse string of the conveying medium gas in the material conveying pipe 10 from causing the biomass material to spontaneously ignite before entering the venturi pipe 11;

27) Judging whether the biomass in the hopper 1 spontaneously combusts through the first temperature measuring point 14 on the hopper 1, and if it spontaneously combusts, the fire-fighting device 17 is put into operation automatically or on-site;

28) When the biomass material in the hopper 1 is blocked, the rapping device 16 is put into operation automatically or on the spot.

The specific operations in the outage phase are:

31) Check the entire system, keep the variable frequency motor 3, valve 8 and gate door 13 in a closed state; confirm that the top cover plate 5 is in a closed state; confirm that the material conveying pipeline 10 is in a running state;

32) Stop the feeding of the hopper 1 in turn, turn off the frequency conversion motor 3 after confirming that the hopper 1 is empty through the observation window 2, and close the valve 8 and the gate door 13 at the lower part of the blanking pipe 6 at the same time, and each operation interval is 1-5 minutes;

33) Confirm that the variable frequency motor 3, the valve 8, the gate 13 and the top cover 5 are closed.

The present invention has the following characteristics:

1. Prevent the reverse string of the conveying medium gas

The general pneumatic conveying pipeline is basically in a positive pressure operation state. In order to prevent the conveying medium gas in the pipeline from entering the biomass feeding system, three designs are carried out: 1) The screw feeder 4 is used instead, which can make the material Continuously advance downstream without gaps; 2) Install a gas sealing device 7 at the lower part of the blanking pipe 6 to achieve gas sealing, and then guide the biomass material to advance downward through the direction of the sealed airflow and the design of the flow field; A Venturi tube 11 is installed in the conveying pipeline section below the material pipe 6, which utilizes the flow of gas in the conveying pipeline to generate negative pressure and reduces the kinetic energy of reverse series from the source.

2. High feeding accuracy

The present invention is equipped with a screw feeder 4 with a frequency conversion motor 3 as a power source, the screw feeder 4 can realize uninterrupted and continuous feeding of materials, and the feeding density is uniform; the frequency conversion motor 3 can be flexible according to the material requirements. Adjust the feeding amount, the above two configurations can realize the precise feeding of the system.

3. Multi-level anti-blocking design

Aiming at the problem of anti-clogging of materials, the present invention has carried out a special design: 1) a material level gauge 15 and an observation window 2 are installed on the hopper 1, which can remotely and locally determine the feeding status of the hopper 1 in real time; 2) a vibrator is installed on the hopper 1 The punching device 16 can prevent the material from sticking to the wall in the hopper 1 and the blockage caused by bridging; 3) The top cover plate 5 is provided with an observation hole, which can check on the spot whether the blanking pipe 6 is blocked. When the blanking pipe 6 is blocked , the top cover plate 5 can be opened for processing; 4) The airflow of the gas sealing device 7 has a drainage effect on the biomass material, which can prevent the material from clogging at the lower part of the blanking pipe 6; 5) The negative pressure generated by the venturi pipe 11 can inhibit the The material caused by the reverse flow of the air flow in the conveying pipeline is blocked at the lower part of the blanking pipe 6;

4. High reliability

The main equipment, pipelines, gate 13, valve 8 and other components of the present invention operate under normal temperature and pressure, and individual components operate under low pressure conditions, and the operating state is safe and reliable; the two-stage gate 13 can transport materials in the equipment during the process of Effective isolation within the required time; equipped with a number of biomass material anti-blocking, conveying medium gas anti-reverse series designs; materials can be remotely and locally monitored in real time during the entire process; hopper 1 and blanking pipe 6 are equipped with temperature measuring points, It can predict whether the biomass material spontaneously ignites; the hopper 1 is equipped with a fire fighting device 17, which can put out the fire in time when spontaneous combustion occurs.

5. Low construction cost

The main components such as the hopper 1, the frequency conversion motor 3, the screw feeder 4, the blanking pipe 6, the gate door 13, the valve 8, the pipeline and the temperature measuring point of the present invention operate under the condition of normal pressure and non-corrosive atmosphere, and the materials are free from Special requirements, and the power of the variable frequency motor 3 is small, so the equipment purchase cost is low; in the present invention, each component can be arranged on the ground, and the weight is light, so the installation cost is low.

6. Low operating cost

The present invention has no high-power electrical equipment and has low power consumption; the gas sealing device 7 is compressed air or flue gas at room temperature, with low pressure level and low acquisition cost; the present invention can realize real-time monitoring and program-controlled control, and the operation input labor cost is low.

7. Small maintenance

In the present invention, each component operates under normal temperature and pressure, and the operating environment is good, so the equipment loss is small and the service life is long; each component can be disassembled and repaired separately, and each main turning machine can be manually adjusted, and automatic program control can also be realized; The parts do not need special maintenance after transportation, so the maintenance is small.

Claims (9)

1. A biomass material feeding system for preventing the reverse string of conveying medium gas is characterized in that, comprising a hopper (1), a screw feeder (4), a blanking pipe (6), a venturi pipe (11), a material conveying A pipeline (10), a variable frequency motor (3) and a sealed air pipeline (9); The bottom outlet of the hopper (1) is communicated with the inlet of the screw feeder (4), and the outlet of the screw feeder (4) is communicated with the inlet on the side of the blanking pipe (6). The outlet is communicated with the top inlet on the side of the throat of the venturi tube (11), and the material conveying pipeline (10) is communicated with the inlet of the venturi tube (11); The output shaft of the variable frequency motor (3) is connected with the drive shaft of the screw feeder (4), a gate (13) is arranged at the bottom outlet of the hopper (1), and an observation window (13) is arranged on the side of the hopper (1). 2), the top opening of the blanking pipe (6) is provided with an end top cover plate (5); A gas sealing device (7) is arranged on the side of the blanking pipe (6), wherein the sealing air pipeline (9) is communicated with the gas sealing device (7), and a valve (7) is arranged on the sealing air pipeline (9). 8). 2. The biomass material feeding system according to claim 1, characterized in that a thread, a flange or a hinge is used between the top cover plate (5) and the blanking pipe (6). connect. 3 . The biomass material feeding system according to claim 1 , wherein a material guide plate ( 12 ) is arranged in the venturi tube ( 11 ). 4 . 4. The biomass material feeding system according to claim 1, characterized in that, the lower side of the hopper (1) is a conical structure or a hyperbolic structure, and the upper side of the hopper (1) is a conical structure or a hyperbolic structure. It is a cylindrical structure or a cuboid structure. 5 . The biomass material feeding system according to claim 1 , characterized in that an observation hole is provided on the end top cover plate ( 5 ). 6 . 6 . The biomass material feeding system according to claim 1 , wherein the observation window ( 2 ) is provided with a scale indication. 7 . 7. The biomass material feeding system according to claim 1, characterized in that, the blanking pipe (6) is provided with a second temperature measuring point, and the second temperature measuring point is located on the top cover plate (5) and the gas sealing device (7). 8 . The biomass material feeding system according to claim 1 , wherein the hopper ( 1 ) is provided with a first temperature measuring point ( 14 ) and a material level gauge ( 15 ). 9 . 9 . The biomass material feeding system according to claim 1 , wherein a fire fighting device ( 17 ) and a rapping device ( 16 ) are arranged on the side of the hopper ( 1 ). 10 .

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