Mechanical grinding equipment for harmless treatment of fly ash

Abstract

The invention belongs to the technical field of fly ash treatment equipment, and discloses mechanical grinding equipment for harmless treatment of fly aste.The mechanical grinding equipment comprises a mixing unit, a grinding unit and a collecting unit, and the mixing unit comprises a first feeding hopper, a second feeding hopper, a stirring machine and a collecting hopper; the grinding unit comprises a first grinding mechanism and a second grinding mechanism which are perpendicular to each other, and the collecting unit comprises a cyclone separator, a bag filter and an induced draft fan. According to the invention, the two grinding assemblies connected in series are used for full grinding, and impact and flow along with high-speed irregular rotation of air under the action of high-speed impact of machinery and high-speed rotational flow and impact of air, so that a mechanical disturbance effect and a chemical effect are formed, and the effect of degrading and removing harmful toxic substances in fly ash is achieved. The fly ash is subjected to harmless treatment through mechanical equipment, the equipment is simple and easy to operate, full-automatic, easy to repair and maintain, small in occupied area, low in construction cost and more suitable for being put into use in a small waste incineration plant.

Description

Technical Field

[0001] The present application relates to the technical field of fly ash processing equipment, and more specifically, to a mechanical grinding equipment for harmlessly processing fly ash. Background Art

[0002] With the widespread application of incineration technology in hazardous waste treatment, fly ash treatment in hazardous waste incineration plants will be a hot topic and a difficult problem in the current environmental field. This is because the fly ash output is large, and it contains a large amount of heavy metal elements, salts, and highly toxic dioxins and other pollutants, which are listed in the HW18 category of the National Hazardous Waste List. Therefore, fly ash must be disposed of in accordance with the standards for hazardous waste, and must be harmlessly disposed of before it can be used as a resource.

[0003] The output of fly ash is related to the type of garbage, incineration conditions, incinerator type and flue gas treatment process, and generally accounts for about 3% to 5% of the amount of garbage incinerated. Due to the continuous generation of urban garbage, domestic garbage incineration power plants maintain high-load operation all year round, increasing the emission and treatment needs of pollutants such as nitrogen oxides, dioxins, fly ash, and odorous gases. If they are not properly handled, it will bring environmental problems and social impacts; measures must be taken to promote the coordinated development of garbage incineration treatment capacity and incineration fly ash harmless disposal technology.

[0004] Municipal waste incineration fly ash is a highly alkaline fly ash with a Ph value of about 13, a surface area of ​​13.05㎡ / g, and a dioxin toxicity equivalent of 87-200 nanograms per kilogram. The Cl content in the fly ash reaches 20-40%.

[0005] At present, there is no effective technology to completely solve the problem of harmless treatment and resource recycling of garbage fly ash in various garbage incineration plants. Existing studies have shown that melting treatment can completely decompose dioxins in fly ash, and the low-boiling heavy metal elements and their compounds contained in the fly ash are volatilized and transferred to the air, while the remaining metals are transferred to glass slag. The high-temperature oxidizing atmosphere melting treatment is either to design special equipment or to use the pelletizing vertical furnace, sintering furnace, steelmaking converter, etc. in the ironmaking equipment. However, when the high-temperature oxidizing atmosphere melting treatment is used, when the melting temperature is above 800°C, the trivalent chromium in the heavy metals will be completely converted into hexavalent chromium, and hexavalent chromium is an ingested poison / inhaled extremely toxic substance. Skin contact may cause sensitivity, and it is more likely to cause hereditary gene defects. Inhalation may cause cancer and has a lasting danger to the environment. This is not allowed in domestic and foreign environmental protection standards. The use of high-temperature reducing atmosphere melting method can effectively avoid this problem, but the current high-temperature reducing atmosphere melting methods at home and abroad all use special high-temperature reducing atmosphere melting equipment, but the construction and operation costs of these equipment are extremely high, making it difficult to implement industrialization. Thereby limiting the harmless treatment of garbage fly ash.

[0006] Patent CN106734099A discloses a process for high-temperature harmless disposal of waste incineration fly ash using secondary material composite technology, which includes the following steps: (1) waste incineration fly ash is used as a core material, a reducing agent containing a C raw material is added, or a chlorine absorbent and / or additive containing CaO is further added, and a core is made under the action of an adhesive; the dry weight ratio of the waste incineration fly ash, the reducing agent, the chlorine absorbent, and the additive is 50-80%, 10-30%, 0-6%, and 0-15% respectively; (2) the core and the chlorine absorbent containing CaO are mixed, and a layer of chlorine absorbent is formed on the outside of the core under the action of an adhesive. shielding layer, forming pellets, the amount of chlorine absorbent accounts for 3-10% of the weight of the dry composite ball; (3) the pellets prepared in step (2) and the shell material are wrapped with a shell on the outside under the action of an adhesive through a ball making device to form a secondary material composite pellet; the shell material uses non-toxic and harmless materials and other additives; (4) the secondary material composite pellets are finally incinerated in an incineration device for high-temperature harmless disposal; the incineration device uses a metallurgical sintering machine or a solid waste harmless incineration device; the moisture content of the ball core is controlled to be 18-28%, the diameter of the ball core is 1-3 mm, the compressive strength is greater than 7N / piece, and the drop strength is greater than 20 times / piece. Although this process effectively solves the above problems, it is necessary to add a chlorine absorbent and a C-containing reducing agent or a melting additive before forming the ball core, and it is necessary to form a ball again after pre-coating. The process is relatively complicated and cumbersome, which is not conducive to saving time and space. The required equipment occupies a large area and is not suitable for construction in a waste incineration plant with a small open space area. Summary of the invention

[0007] In order to solve the above problems, the present application provides a mechanical grinding device for harmless treatment of fly ash.

[0008] The present application provides a mechanical grinding device for harmless treatment of fly ash using the following technical solution:

[0009] A mechanical grinding device for harmless treatment of fly ash, comprising:

[0010] A mixing unit, the mixing unit comprising a first upper hopper, a second upper hopper, a mixer and a collecting hopper, the discharge ports of the first upper hopper and the second upper hopper are respectively connected to the feed port of the mixer, and are used to mix the fly ash to be treated and the additive, and the discharge port of the mixer is connected to the collecting hopper;

[0011] A grinding unit, the grinding unit comprising a first grinding mechanism and a second grinding mechanism arranged perpendicular to each other, the feed port of the first grinding mechanism being connected to the discharge port of the collecting hopper for performing preliminary grinding on the mixed material, the feed port of the second grinding mechanism being connected to the discharge port of the first grinding mechanism for performing secondary grinding on the material after preliminary grinding;

[0012] The collecting unit is used to separate and collect the ground products, and the collecting unit includes a cyclone separator, a bag filter and an induced draft fan. The feed port of the cyclone separator is connected to the discharge port of the second grinding mechanism, the exhaust port of the cyclone separator is connected to the air inlet of the bag filter, and the induced draft fan is connected to the exhaust port of the bag filter. The bottom ends of the cyclone separator and the bag filter are both provided with discharge valves, and the final product after grinding is discharged through the discharge valve.

[0013] Furthermore, the first upper hopper and the second upper hopper are arranged side by side, and a first screw feeder is arranged between the bottom discharge ports of the first upper hopper and the second upper hopper. The first screw feeder is a double-end bidirectional feeder, and its discharge port is located in the middle. The mixer is arranged below the discharge port of the first screw feeder.

[0014] Furthermore, a second screw feeder is provided at the bottom discharge port of the mixer, and the discharge port of the second screw feeder is located above the feed port of the collecting hopper.

[0015] Furthermore, the first grinding mechanism includes a laterally arranged cylindrical shell, a cover plate, a grinding assembly and a classifying wheel, a feed port is arranged at the rear of the shell, the grinding assembly is arranged inside the shell, the cover plate and the shell are detachably fixedly connected, a separation chamber is arranged at the center of the cover plate, a discharge port is arranged on the side wall of the separation chamber, the classifying wheel is rotatably connected in the separation chamber, and the rotating shaft of the classifying wheel is connected to an external motor.

[0016] Furthermore, the grinding assembly includes a grinding gear ring and a grinding disc, the grinding gear ring is fixedly connected to the inner wall of the shell, the grinding disc is located inside the grinding gear ring, the edge array of the grinding disc is fixedly connected to a plurality of grinding blades, the center of the grinding disc is fixedly connected to a grinding shaft, the grinding shaft passes through the center position of the rear of the shell and is connected to an external motor.

[0017] Furthermore, the grinding gear ring and the grinding disc are respectively provided in two groups.

[0018] In summary, the present application includes at least one of the following beneficial technical effects:

[0019] (1) The present invention can preliminarily stir and mix the fly ash and additives through a stirring unit, and fully grind them through two grinding components connected in series. Under the high-speed mechanical impact and high-speed rotating flow and impact of air, the high-speed irregular rotation of the air impacts and flows with each other, forming a mechanical disturbance effect and a chemical effect, thereby achieving the effect of degrading and removing harmful and toxic substances in the fly ash;

[0020] (2) The present invention uses mechanical equipment to harmlessly treat fly ash. The equipment is simple and easy to operate, fully automated, and easy to maintain. It has the advantages of high efficiency and short reaction time, no sewage, no smoke, and no dusty exhaust gas discharge. The required equipment occupies a small area and has a low construction cost, making it more suitable for use in small waste incineration plants. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the structure of this application;

[0022] Figure 2 is a cross-sectional view of the first grinding mechanism;

[0023] Figure 3 Schematic diagram of the structure of the grinding disc.

[0024] Description of the numbers in the figure:

[0025] 1. Mixing unit; 11. First feeding hopper; 12. Second feeding hopper; 13. Mixer; 14. Collecting hopper; 15. First screw feeder; 16. Second screw feeder; 2. Grinding unit; 21. First grinding mechanism; 211. Shell; 212. Cover plate; 213. Grinding assembly; 2131. Grinding gear ring; 2132. Grinding disc; 2133. Grinding blade; 2134. Grinding shaft; 214. Classifying wheel; 215. Separation chamber; 22. Second grinding mechanism; 3. Collecting unit; 31. Cyclone separator; 32. Bag filter; 33. Draft fan; 34. Discharge valve. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application; obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments, and all other embodiments obtained by ordinary technicians in this field based on the embodiments in the present application without making creative work are within the scope of protection of the present application.

[0027] In the description of the present application, it should be noted that the terms "upper", "lower", "inner", "outer", "top / bottom" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present application. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0028] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "set / connected", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0029] Embodiment 1:

[0030] The present application is further described in detail below in conjunction with the accompanying drawings.

[0031] The present application embodiment discloses a mechanical grinding device for harmless treatment of fly ash, comprising:

[0032] The mixing unit 1 comprises a first upper hopper 11, a second upper hopper 12, a mixer 13 and a collecting hopper 14. The discharge ports of the first upper hopper 11 and the second upper hopper 12 are respectively connected to the feed port of the mixer 13, and are used to mix the fly ash to be treated and the additive. The discharge port of the mixer 13 is connected to the collecting hopper 14.

[0033] The grinding unit 2 includes a first grinding mechanism 21 and a second grinding mechanism 22 which are arranged perpendicular to each other. The feed port of the first grinding mechanism 21 is connected to the discharge port of the collecting hopper 14, and is used to perform preliminary grinding on the mixed material. The feed port of the second grinding mechanism 22 is connected to the discharge port of the first grinding mechanism 21, and is used to perform secondary grinding on the material after preliminary grinding.

[0034] The collecting unit 3 is used to separate and collect the ground products. The collecting unit 3 includes a cyclone separator 31, a bag filter 32 and an induced draft fan 33. The feed port of the cyclone separator 31 is connected to the discharge port of the second grinding mechanism 22, the exhaust port of the cyclone separator 31 is connected to the air inlet of the bag filter 32, the induced draft fan 33 is connected to the exhaust port of the bag filter 32, and the bottom ends of the cyclone separator 31 and the bag filter 32 are both provided with discharge valves 34, and the final product after grinding is discharged by the discharge valve 34.

[0035] See also Figure 1 The first upper hopper 11 and the second upper hopper 12 are arranged side by side, and a first screw feeder 15 is arranged between the bottom discharge ports of the first upper hopper 11 and the second upper hopper 12. The first screw feeder 15 is a double-end bidirectional feeder, and its discharge port is located in the middle. The mixer 13 is arranged below the discharge port of the first screw feeder.

[0036] See also Figure 1A second screw feeder 16 is provided at the bottom discharge port of the mixer 13 , and the discharge port of the second screw feeder 16 is located above the feed port of the collecting hopper 14 .

[0037] See also Figure 2 The first grinding mechanism 21 includes a laterally arranged cylindrical shell 211, a cover plate 212, a grinding assembly 213 and a classifying wheel 214. A feed port is arranged at the tail of the shell 211, and the grinding assembly 213 is arranged inside the shell 211. The cover plate 212 and the shell 211 are detachably fixedly connected. A separation chamber 215 is arranged at the center of the cover plate 212, and a discharge port is arranged on the side wall of the separation chamber 215. The classifying wheel 214 is rotatably connected in the separation chamber 215, and the rotating shaft of the classifying wheel 214 is connected to an external motor.

[0038] See also Figure 2 and Figure 3 The grinding assembly 213 includes a grinding gear ring 2131 and a grinding disc 2132. The grinding gear ring 2131 is fixedly connected to the inner wall of the shell 211, and the grinding disc 2132 is located inside the grinding gear ring 2131. The edge array of the grinding disc 2132 is fixedly connected to a plurality of grinding blades 2133. The center of the grinding disc 2132 is fixedly connected to a grinding shaft 2134. The grinding shaft 2134 passes through the center position of the rear of the shell 211 and is connected to an external motor.

[0039] Preferably, the grinding gear ring 2131 and the grinding disc 2132 are respectively provided in two groups.

[0040] The implementation principle of a mechanical grinding device for harmless treatment of fly ash in the embodiment of the present application is as follows: when in use, the fly ash material to be ground and the additive are added from the first upper hopper 11 and the second upper hopper 12 respectively, and then stirred evenly by the mixer 13, and the fully stirred material is sent to the first grinding mechanism 21 for grinding, and the material is fully ground by the shearing action between the grinding tooth ring 2131 and the grinding blade 2133 on the grinding disc 2132, and the particles meeting the particle size requirements are sent out from the discharge port under the action of the grading wheel 214, and then enter the second grinding mechanism 22, and the second grinding machine 2131 is used for grinding. The structure of the structure 22 is similar to the internal structure of the first grinding mechanism 21, and its function is to further mix and grind the particles ground by the first grinding mechanism 21. Then, under the action of the induced draft fan 33 set at the rear end, the airflow first sucks the particles into the cyclone separator 31, and the heavier fly ash particles are first discharged from the discharge port below the cyclone separator 31, while the dust-containing gas enters the bag filter 32 from the exhaust port of the cyclone separator 31. Then, the clean gas after filtration is discharged from the exhaust port of the induced draft fan 33, and the tiny particles are discharged from the discharge port below the bag filter 32, completing the collection of the ground materials. Strong mechanical disturbance is generated under the action of the mechanical energy of the stirring equipment and the grinding equipment, so that the fly ash and additives such as citric acid are fully mixed, and they collide and impact with each other repeatedly, and free radicals are generated at the same time. Therefore, under the high-speed mechanical impact and the high-speed rotating flow and impact of the air, the materials, under the action of mechanical energy, impact and flow with each other with the high-speed irregular rotation of the air, forming a mechanical disturbance effect and a chemical effect, so that the materials and fly ash repeatedly impact at high speed, and anions and cations are leached, and at the same time, oxygen atoms continuously attack the C bond, and physical and chemical reactions occur at the same time, achieving the effect of degrading and removing harmful and toxic substances in the fly ash. The present invention utilizes mechanical equipment to perform harmless treatment on fly ash. The equipment is simple and easy to operate, can be fully automated, and is easy to repair and maintain. It has the advantages of high efficiency and short reaction time, no sewage, no smoke, and no dust-containing exhaust gas discharge, the required equipment occupies a small area, and the construction cost is low, which is more suitable for use in small-scale waste incineration plants.

[0041] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A mechanical grinding device for harmless treatment of fly ash, characterized in that: include: A mixing unit (1), the mixing unit (1) comprising a first upper hopper (11), a second upper hopper (12), a mixer (13) and a collecting hopper (14), the discharge ports of the first upper hopper (11) and the second upper hopper (12) being respectively connected to the feed port of the mixer (13) for mixing the fly ash to be treated and the additive, and the discharge port of the mixer (13) being connected to the collecting hopper (14); A grinding unit (2), the grinding unit (2) comprising a first grinding mechanism (21) and a second grinding mechanism (22) which are arranged perpendicular to each other, the feed inlet of the first grinding mechanism (21) being connected to the discharge port of the collecting hopper (14) for performing preliminary grinding of the mixed material, the feed inlet of the second grinding mechanism (22) being connected to the discharge port of the first grinding mechanism (21) for performing secondary grinding of the material after preliminary grinding; A collecting unit (3) is used to separate and collect the ground product. The collecting unit (3) comprises a cyclone separator (31), a bag filter (32) and an induced draft fan (33). The feed port of the cyclone separator (31) is connected to the discharge port of the second grinding mechanism (22). The exhaust port of the cyclone separator (31) is connected to the air inlet of the bag filter (32). The induced draft fan (33) is connected to the exhaust port of the bag filter. The bottom ends of the cyclone separator (31) and the bag filter (32) are both provided with discharge valves (34). The final product after grinding is discharged through the discharge valve (34).

2. The mechanical grinding equipment for harmless treatment of fly ash according to claim 1 is characterized in that: The first upper hopper (11) and the second upper hopper (12) are arranged side by side, and a first screw feeder (15) is arranged between the bottom discharge ports of the first upper hopper (11) and the second upper hopper (12). The first screw feeder (15) is a double-end bidirectional feeder, and its discharge port is located in the middle. The mixer (13) is arranged below the discharge port of the first screw feeder (15).

3. The mechanical grinding equipment for harmless treatment of fly ash according to claim 1 is characterized in that: The bottom outlet of the mixer (13) is provided with a second screw feeder (16), and the outlet of the second screw feeder (16) is located above the feed inlet of the collecting hopper (14).

4. The mechanical grinding equipment for harmless treatment of fly ash according to claim 1 is characterized in that: The first grinding mechanism (21) comprises a transversely arranged cylindrical shell (211), a cover plate (212), a grinding assembly (213) and a classifying wheel (214); a feed port is arranged at the rear of the shell (211); the grinding assembly (213) is arranged inside the shell (211); the cover plate (213) and the shell (211) are detachably fixedly connected; a separation chamber (215) is arranged at the center of the cover plate (211); a discharge port is arranged on the side wall of the separation chamber (215); the classifying wheel (214) is rotatably connected in the separation chamber (215); and a rotating shaft of the classifying wheel (214) is connected to an external motor.

5. The mechanical grinding equipment for harmless treatment of fly ash according to claim 4 is characterized in that: The grinding assembly (213) comprises a grinding gear ring (2131) and a grinding disc (2132); the grinding gear ring (2131) is fixedly connected to the inner wall of the housing (211); the grinding disc (2132) is located inside the grinding gear ring (2131); a plurality of grinding blades (2133) are fixedly connected to the edge array of the grinding disc (2132); a grinding shaft (2134) is fixedly connected to the center of the rear of the housing (211) and is connected to an external motor.

6. The mechanical grinding equipment for harmless treatment of fly ash according to claim 5, characterized in that: The grinding gear ring (2131) and the grinding disc (2132) are respectively provided in two groups.

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