Waste salt oxidation incinerator and related disposal system

Abstract

The utility model discloses a waste salt oxidation incinerator and a related disposal system. An oxidation reaction area, an air distribution area and a slag falling area are sequentially arranged in a furnace body of the waste salt oxidation incinerator in the direction from the top to the bottom. The oxidation reaction area is provided with a flue gas outlet, and the slag falling area is provided with a salt slag discharge port; a waste salt inlet is formed in the furnace body between the oxidation reaction area and the air distribution area; an air supply device is mounted in the air distribution area, an air supply opening, a material channel and a plurality of air outlets are formed in an air supply device body, the air outlets are distributed in the cross section of the air distribution area, and the air outlet direction of each air outlet faces the oxidation reaction area; and the material channel realizes communication between the oxidation reaction area and the slag falling area. The disposal system adopts the incinerator provided by the utility model. When the incinerator is used, waste salt particles enter the oxidation incinerator through pneumatic conveying, the waste salt particles are in a homogeneous suspension state in the incinerator, heat and mass transfer between the waste salt particles and high-temperature flue gas fed from the bottom of the incinerator is strong, the oxidation incineration speed of organic matter is high, and the organic matter is thoroughly removed.

Description

Technical Field

[0001] The utility model belongs to the technical field of industrial waste salt treatment and relates to a waste salt oxidation incinerator and a system. Background Art

[0002] Industrial waste salt mainly refers to solid waste with inorganic salts (sodium chloride, sodium sulfate, potassium chloride, etc.) as the main components. It can be divided into two categories based on the source: the first category is water treatment, including pure water preparation, chemical preparation (softening), and high-salt wastewater treatment; the second category is by-products of chemical production. Statistics show that my country's waste salt production reached 23.61 million tons in 2021.

[0003] Because waste salt contains a certain amount of organic matter and is water-soluble, the conventional disposal method is rigid landfill. However, this method imposes a heavy economic burden on enterprises, and the landfill method occupies a large amount of land resources. In recent years, resource recycling has become a way to achieve green and sustainable development of waste salt.

[0004] One means of resource disposal of waste salt is through oxidation incineration, that is, the organic matter in the waste salt is rapidly oxidized and decomposed in a rotary kiln at a temperature below the melting point. If the total organic carbon of the treated salt reaches a certain standard, it can be used as a production raw material for the chlor-alkali and other industries.

[0005] However, in the process of rotary kiln oxidation incineration, waste salt is easy to accumulate in the equipment, the material is not fully in contact with the oxygen in the air, the organic matter in the material is not fully oxidized, and even oxygen-free pyrolysis occurs. The organic matter will be carbonized and exist in the product in the form of fixed carbon, affecting the quality of the product. At the same time, the accumulation of waste salt will also cause uneven heating, and local waste salt is easy to overheat and melt, causing contamination of the rotary kiln equipment, seriously affecting the disposal efficiency of the equipment. Utility Model Content

[0006] The defects or shortcomings of the prior art are addressed by the present invention.

[0007] To this end, the waste salt oxidation incinerator provided by the utility model comprises a furnace body, wherein an oxidation reaction zone, an air distribution zone and a slag dropping zone are sequentially arranged in the furnace body from top to bottom; the oxidation reaction zone is provided with a smoke outlet, and the slag dropping zone is provided with a salt slag discharge port;

[0008] A waste salt inlet is provided on the furnace body, and the waste salt inlet is axially located between the oxidation reaction zone and the air distribution zone;

[0009] The air distribution area is equipped with an air supply device, and the air supply device body is provided with an air supply port, a material channel and multiple air outlets. The air supply port is connected with the multiple air outlets, and the multiple air outlets are distributed on the cross-section of the air distribution area, and the air outlet direction of each air outlet is toward the oxidation reaction area; the material channel realizes the connection between the oxidation reaction zone and the slag falling zone.

[0010] An optional solution is that the air supply device body includes an air supply port and multiple pipes, the multiple pipes are arranged in the air distribution area, gaps are left between adjacent pipes to form material channels, and each pipe is provided with a number of air outlets; the multiple pipes are all connected to the air supply port.

[0011] An optional solution is that each pipeline is provided with a plurality of outlets, each outlet is connected to a branch pipe, and the branch pipe extends toward the oxidation reaction zone, and the outlet of each branch pipe is an air outlet.

[0012] An optional solution is that the pipelines are installed radially along the furnace body and are distributed in parallel and at equal intervals; and the multiple air outlets are distributed at equal intervals on the cross section of the air distribution area.

[0013] An optional solution is that the volume of the oxidation reaction zone is larger than the volume of the air distribution zone and larger than the volume of the slag dropping zone.

[0014] An optional solution is that the axial size and radial size of the oxidation reaction zone are larger than the axial size and radial size of the air distribution zone, and larger than the axial size and radial size of the slag dropping zone.

[0015] An optional solution is that the area of ​​the oxidation reaction zone close to the air distribution zone is an inverted cone structure.

[0016] An optional solution is that a secondary air inlet is provided on the furnace wall of the oxidation reaction zone, and in the axial direction, the secondary air inlet is located above the waste salt inlet.

[0017] An optional solution is that, along the axial direction, a smoke outlet is provided at the top of the furnace body, and a salt slag discharge port is provided at the bottom.

[0018] The utility model also provides a waste salt oxidation incineration disposal system. The disposal system comprises the waste salt oxidation incinerator, a cyclone separator and a flue gas purification system; the waste salt oxidation incinerator, the cyclone separator and the flue gas purification system are connected in sequence.

[0019] The utility model solves the problems in the prior art that organic matter is not fully exposed to oxygen and is easy to be carbonized, and is unevenly heated and is easy to melt and contaminate the equipment during the process of treating waste salt with rotary kiln equipment.

[0020] When the waste salt oxidation incinerator of the utility model is used, the waste salt is ground into small particles and is pneumatically conveyed into the oxidation incinerator. It is in a homogeneous suspended state in the incinerator, and has strong heat and mass transfer with the upward high-temperature flue gas sent into the furnace from the bottom of the incinerator. The oxidation and incineration rate of organic matter is high and the removal is thorough.

[0021] When the waste salt oxidation incinerator of the utility model is used for treatment, the waste salt particles are heated more evenly in the incinerator, and are not prone to local high-temperature melting, and will not contaminate the inner wall of the equipment. In addition, part of the agglomerated salt slag falls into the ash hopper through the gap between the air supply components under the action of gravity, and is put into the furnace for recycling after cooling and grinding, without the need to stop the furnace frequently, and the system operates stably and can achieve long-term operation.

[0022] In addition, after disposal, the waste salt will produce no carbon residue and directly form qualified industrial salt, thus realizing the resource recycling of waste salt.

[0023] The utility model proposes a novel waste salt oxidation incinerator and system in view of the fact that organic matter in conventional rotary kiln equipment is not fully exposed to oxygen and is easily carbonized, and is unevenly heated and easily melted and contaminated by the equipment during the waste salt treatment process. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the internal area distribution of the waste salt oxidation incinerator of the utility model.

[0025] Figure 2 It is a structural schematic diagram of the waste salt oxidation incinerator of the utility model.

[0026] Figure 3 It is a schematic diagram of the structure of the air supply device in the embodiment of the utility model.

[0027] Figure 4 for Figure 3 Top view of the .

[0028] Figure 5 This is a flow chart of the waste salt oxidation incineration disposal system in the embodiment of the utility model.

[0029] Figure 6 This is another flow chart of the waste salt oxidation incineration disposal system in the embodiment of the utility model. DETAILED DESCRIPTION

[0030] Unless otherwise specified, the scientific and technical terms used herein are understood according to the knowledge of ordinary technicians in the relevant fields.

[0031] The axial, radial, up, down, top, bottom and other direction or orientation terms described in this article are consistent with the relevant directions or orientations in the drawings of the specification. It should be noted that the drawings of the specification are intended to explain the utility model. The equivalent schemes obtained by rotation, replacement, etc. based on the contents disclosed in this article are all within the protection scope of the utility model.

[0032] The present utility model is described in detail below with reference to the accompanying drawings and specific implementation methods.

[0033] Embodiment 1:

[0034] See also Figure 1 and 2 As shown, the waste salt oxidation incinerator of the utility model comprises a furnace body 1, in which an oxidation reaction zone A, an air distribution zone B and a slag falling zone C are arranged from top to bottom in sequence, wherein a smoke outlet 8 is arranged at the top of the oxidation reaction zone A, and a salt slag discharge port 7 is arranged at the bottom of the slag falling zone;

[0035] A waste salt inlet 4 is provided on the furnace body between the oxidation reaction zone A and the air distribution zone B;

[0036] The air distribution area is provided with an air supply device 5, and the air supply device body is provided with an air supply port, a material channel and multiple air outlets. The multiple air outlets are distributed on the cross-section of the air distribution area, and the air outlet of each air outlet is directed toward the oxidation reaction area. The air supply port is connected to the hot air outside, and after entering the air supply device, it enters the furnace through the air outlet.

[0037] During operation, high-temperature flue gas of 500-900°C (this temperature is determined by the composition of the waste salt, preferably 100°C lower than the melting temperature of the waste salt) is sent into the furnace through the primary air supply port and the air outlet in turn.

[0038] The waste salt is ground into particles with a particle size of less than 500um, and is sent into the furnace through the waste salt inlet 4 by pneumatic conveying. Under the action of the high-temperature flue gas in the furnace below, the waste salt is suspended and undergoes heat and mass transfer reactions with the high-temperature flue gas. The waste salt particles and the oxygen in the flue gas fully contact and react, and the organic matter is burned and treated. The cleaned purified salt particles and flue gas are discharged through the flue gas outlet; some salt particles in the furnace may undergo high-temperature melting and agglomeration due to local temperature unevenness. At this time, the agglomerated large-particle salt slag will fall into the slag falling area C through the material passage under the action of gravity; by regularly opening the agglomerated salt discharge valve 6, the salt slag is discharged from the salt slag discharge port 7. In addition, part of the slag salt re-enters the grinding system after cooling, and after grinding, it is sent to the furnace for treatment together with the waste salt again.

[0039] In the specific scheme, high-temperature flue gas can be generated by burning natural gas or other fuels in the hot blast furnace, or by extracting part of the flue gas discharged from the flue gas outlet through the flue gas ejector (processed by a cyclone separator), and then mixing it with the high-temperature flue gas generated by the hot blast furnace to generate high-temperature flue gas. The recycling of part of the flue gas can reduce the consumption of natural gas and other fuels in the hot blast furnace, thereby reducing the energy consumption of the system.

[0040] In a specific solution, the inner wall material of the furnace body 1 is a refractory structure 2 .

[0041] The air supply device used in some schemes includes multiple pipes and air supply ports. Multiple pipes are arranged in the air distribution area. There are gaps between adjacent pipes to form a material channel (the gap size is reasonably designed to ensure that the material falls smoothly into the slag drop area, such as a gap of not less than 20mm). Each pipe is provided with a number of air outlets; multiple pipes are connected to the air supply port. Hot air is sent into the furnace through the air supply port, pipes, and air outlets in turn. In the specific scheme, valves and other flow control means are used to make the flow of each pipe branch equal.

[0042] There are also some solutions using the air supply device structure such as Figure 3 and 4 As shown, it includes multiple pipes 503 and a bellows 502. The multiple pipes are arranged in the air distribution area. Gaps are left between adjacent pipes to form a material channel. Each pipe is provided with a number of air outlets; the multiple pipes are connected to the bellows, and the bellows is provided with an air supply port 501. The hot air is sent into the furnace through the air supply port 501, the bellows 502, the pipe 503, and the air outlet in sequence. In a further pre-selected scheme, each pipe of the above scheme is provided with a number of outlets, each outlet is connected to a branch pipe 504, and the branch pipe extends toward the oxidation reaction zone, and the outlet of each branch pipe is an air outlet. In order to prevent waste salt particles from falling into the air outlet, each air outlet is installed with a partition net. In order to ensure that the hot air is evenly delivered to the furnace, the multiple pipes in the above scheme are evenly spaced, and the multiple outlets are evenly spaced on the cross-section of the air distribution area. It should be noted that the distribution method of the multiple air outlets is not limited. Figure 4 The distribution shown is an array, but it can also be distributed in an equilateral triangle.

[0043] In order to reduce the flue gas velocity, increase the residence time of the waste salt in the oxidation reaction zone, and ensure that the waste salt particles are fully heat treated, the volume of the oxidation reaction zone is larger than the volume of the air distribution zone and the volume of the slag falling zone. Figure 1 As shown, the axial size and radial size of the oxidation reaction zone are larger than the axial size and radial size of the air distribution zone, and larger than the axial size and radial size of the slag dropping zone.

[0044] In order to ensure sufficient contact between the material and the hot air, based on the above scheme, the area of ​​the oxidation reaction zone close to the air distribution zone is an inverted cone structure.

[0045] In the specific scheme, in order to ensure the uniformity of material entering the furnace, waste salt inlets can be arranged as needed, and the number is greater than or equal to 1. When the number is greater than 1, they are evenly distributed along the circumference.

[0046] In order to increase the disturbance of waste salt and high-temperature flue gas, a reasonable number of secondary air inlets 3 are added on the furnace wall, and part of the high-temperature flue gas can be sent into the furnace through the secondary air inlets 3. When the number of secondary air inlets is greater than 1, they are evenly distributed along the circumference of the furnace.

[0047] In some other solutions, the furnace wall is provided with a temperature measuring port 9 for monitoring the temperature inside the furnace.

[0048] Embodiment 2:

[0049] The waste salt oxidation incinerator disposal system of this embodiment includes the waste salt oxidation incinerator described in Example 1, a cyclone separator, a flue gas purification system and a hot air furnace. The working process of the system is as follows:

[0050] The hot blast furnace is used to generate high-temperature flue gas, which is supplied to the waste salt oxidation incinerator 1; the purified salt particles treated by the waste salt oxidation incinerator 1 are discharged from the flue gas outlet together with the flue gas, and then enter the cyclone separator, where the purified salt and flue gas are separated, and the purified salt is discharged from the bottom of the cyclone separator, while the flue gas enters the flue gas purification system for further dust removal, denitrification, and deacidification before being discharged after meeting the standards. In a further scheme, the system also includes a flue gas ejector. Based on the above process, part of the flue gas discharged from the cyclone separator is introduced into the waste salt oxidation incinerator 1 through the flue gas ejector for recycling (such as Figure 5 shown).

[0051] Embodiment 3:

[0052] This embodiment utilizes the above embodiment Figure 1-4 (No secondary air vents are provided on the incinerator) and Figure 5 The treatment system treats 30t / d of waste salt, and the components of the treated waste salt are shown in Table 1 below:

[0053] Table 1 Composition of waste salt

[0054] Serial number project unit content 1 Sodium chloride ％ 94.1 2 Moisture ％ 5.74 3 Calcium ％ 0.01 4 Magnesium ion ％ 0.01 5 Sulfate ion ％ 0.06 6 silicon ％ 0.08 7 Total organic carbon mg / kg 14600

[0055] During the treatment, the waste salt is ground into fine particles less than 200um and sent into the furnace by pneumatic conveying; the high-temperature flue gas of 1300℃ generated by the hot blast furnace and the flue gas of 550℃ extracted after the cyclone separator are mixed, and the mixed flue gas with a temperature of 650℃ is sent into the furnace through the primary air component.

[0056] When the system is running, the temperature of the temperature measuring point in the middle of the waste salt oxidation incinerator is 600℃, and the waste salt stays in the furnace for more than 10s; the purified salt discharged from the bottom outlet of the cyclone separator is tested, and the results are shown in Table 2 below:

[0057] Table 2

[0058] NaCl / % Total organic carbon mg / kg Numeric 99.2 90

[0059] It can be seen that the total organic carbon content in the purified salt is less than 100 mg / kg, and can be recycled as a snow-melting agent.

[0060] Embodiment 4:

[0061] This embodiment utilizes Figure 1-4 The incinerator shown (with secondary air outlet) and Figure 6 The system process shown is used for oxidation incineration treatment of 50t / d of waste salt. The composition of the treated waste salt is shown in Table 3:

[0062] Table 3 Chemical composition of waste salt

[0063]

[0064] The waste salt is ground into fine particles less than 280um and pneumatically conveyed into the furnace; the high-temperature flue gas of 680℃ generated by the hot blast furnace is sent into the furnace through the primary air component and the secondary air inlet (primary air accounts for 75% and secondary air accounts for 25%).

[0065] When the system is running, the temperature of the temperature measuring point in the middle of the waste salt oxidation incinerator is 630℃, and the waste salt stays in the furnace for more than 10s. The purified salt discharged from the bottom outlet of the cyclone separator has been tested, and the results are shown in Table 4 below:

[0066] Table 4

[0067] KCL / % KF / % Total organic carbon mg / kg Numeric 84.8 14.4 95

[0068] It can be seen that the total organic carbon content in the purified salt is less than 100 mg / kg, and can be recycled as a snow-melting agent.

Claims

1. A waste salt oxidation incinerator, comprising a furnace body, It is characterized in that The furnace body is provided with an oxidation reaction zone, an air distribution zone and a slag dropping zone in sequence from the top to the bottom; the oxidation reaction zone is provided with a smoke outlet, and the slag dropping zone is provided with a salt slag discharge port; A waste salt inlet is provided on the furnace body, and the waste salt inlet is axially located between the oxidation reaction zone and the air distribution zone; The air distribution area is equipped with an air supply device, and the air supply device body is provided with an air supply port, a material channel and multiple air outlets. The air supply port is connected with the multiple air outlets, and the multiple air outlets are distributed on the cross-section of the air distribution area, and the air outlet direction of each air outlet is toward the oxidation reaction area; the material channel realizes the connection between the oxidation reaction zone and the slag falling zone.

2. The waste salt oxidation incinerator according to claim 1, It is characterized in that The air supply device body comprises an air supply port and a plurality of pipes, wherein the plurality of pipes are arranged in an air distribution area, gaps are left between adjacent pipes to form a material channel, and each pipe is provided with a plurality of air outlets; and the plurality of pipes are all connected to the air supply port.

3. The waste salt oxidation incinerator according to claim 2, It is characterized in that Each pipeline is provided with a plurality of outlets, each outlet is connected with a branch pipe, and the branch pipe extends toward the oxidation reaction zone, and the outlet of each branch pipe is an air outlet.

4. The waste salt oxidation incinerator according to claim 2, It is characterized in that Each pipeline is installed along the radial direction of the furnace body, and is parallel and evenly spaced; the multiple air outlets are evenly spaced on the cross section of the air distribution area.

5. The waste salt oxidation incinerator according to claim 1, It is characterized in that The volume of the oxidation reaction zone is larger than the volume of the air distribution zone and the volume of the slag dropping zone.

6. The waste salt oxidation incinerator according to claim 1, It is characterized in that The axial size and radial size of the oxidation reaction zone are larger than the axial size and radial size of the air distribution zone, and larger than the axial size and radial size of the slag dropping zone.

7. The waste salt oxidation incinerator according to claim 1, 5 or 6, It is characterized in that The area of ​​the oxidation reaction zone close to the air distribution zone is an inverted cone structure.

8. The waste salt oxidation incinerator according to claim 1, It is characterized in that A secondary air inlet is provided on the furnace wall of the oxidation reaction zone, and in the axial direction, the secondary air inlet is located above the waste salt inlet.

9. The waste salt oxidation incinerator according to claim 1, It is characterized in that Along the axial direction, a smoke outlet is provided at the top of the furnace body, and a salt slag discharge port is provided at the bottom.

10. A waste salt oxidation incineration disposal system, It is characterized in that It comprises the waste salt oxidation incinerator, cyclone separator and flue gas purification system as described in claim 1; the waste salt oxidation incinerator, cyclone separator and flue gas purification system are connected in sequence.

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