CN108823412B

CN108823412B - Processing and production process of secondary aluminum

Info

Publication number: CN108823412B
Application number: CN201810635071.7A
Authority: CN
Inventors: 王军伟; 孙会彭; 李亚涛; 王进刚; 孙长克; 肖红军
Original assignee: HENAN MINGTAI ALUMINUM INDUSTRY Co Ltd
Current assignee: HENAN MINGTAI ALUMINUM INDUSTRY Co Ltd
Priority date: 2018-06-20
Filing date: 2018-06-20
Publication date: 2020-02-11
Anticipated expiration: 2038-06-20
Also published as: CN108823412A

Abstract

The invention belongs to the technical field of recycling of secondary aluminum. A processing and production process of secondary aluminum comprises a pretreatment processing procedure, a preheating treatment procedure and a melting and casting procedure; the pretreatment processing procedure comprises the steps of crushing the aluminum waste to form regenerated aluminum blocks, screening the regenerated aluminum blocks to obtain regenerated aluminum blocks with different sizes in different sections, and respectively conveying the regenerated aluminum blocks to corresponding eddy current separators to remove impurities; the preheating treatment process comprises the steps of weighing the regenerated aluminum material block after impurity removal, conveying the regenerated aluminum material block into a preheating furnace, and carrying out preheating, surface depainting, demoulding and waste gas treatment on the regenerated aluminum material block to obtain a pure aluminum material block; the melting and casting process comprises the steps of conveying the pure aluminum material block to a melting furnace for melting, conveying the pure aluminum material block to a melting and holding furnace, refining and blending alloy grades, and casting large aluminum plate ingots by a casting machine. The whole production process reduces the production cost, reduces the environment-friendly emission of greenhouse gases and toxic gases, improves the quality of the aluminum alloy, and promotes the development of the field of the recycled aluminum alloy in China.

Description

Processing and production process of secondary aluminum

Technical Field

The invention belongs to the technical field of recycling of secondary aluminum, and particularly relates to a processing and production process of secondary aluminum such as waste extruded sections, ring-pull cans, aluminum radiators, aluminum plates, waste aluminum products and the like.

Background

The recycled aluminum alloy waste has large yield at home and abroad and needs to be recycled. At present, the recycling technology of the regenerated aluminum alloy is relatively immature, the traditional recycling of the aluminum alloy waste has a plurality of defects in the aspects of crushing, sorting, dust removal, waste environment protection and the production efficiency of the whole process, so that the utilization rate of the aluminum alloy waste is low, the purity of the produced product is not up to standard, the product cannot be supplied to the production and use of high-end products, and a large amount of waste gas and waste dust can be generated to cause atmospheric pollution; due to the fact that the whole process is not coordinated, intermittent work exists in the whole production process, continuous and uninterrupted operation cannot be achieved, production efficiency is low, production cost is high, and further exploration and development of the whole process are not facilitated.

Disclosure of Invention

The invention aims to solve the problems and the defects, and provides a processing and production process for recycled aluminum, which has the advantages of reasonable structural design, high production efficiency, capability of ensuring the quality of aluminum alloy, reduction in production cost and waste discharge control.

In order to achieve the purpose, the adopted technical scheme is as follows:

a processing and production process of secondary aluminum comprises a pretreatment processing procedure, a preheating treatment procedure and a melting and casting procedure; wherein: the pretreatment processing procedure comprises the steps of crushing the aluminum waste to form a regenerated aluminum material block, and screening to obtain regenerated aluminum material blocks with different sizes in different sections; respectively conveying the regenerated aluminum blocks of all the size sections to corresponding eddy current separators to remove impurities; the preheating treatment process comprises the steps of weighing the regenerated aluminum material block after impurity removal, conveying the regenerated aluminum material block into a preheating furnace, and carrying out preheating, surface depainting, stripping and waste gas treatment on the regenerated aluminum material block to obtain a pure aluminum material block; and the melting casting process is to convey the pure aluminum material block to a melting furnace for melting, convey the pure aluminum material block to a melting and holding furnace, refine and allocate the alloy grade, and cast the large aluminum plate ingot by a casting machine after the allocation ratio is detected to be qualified.

In the pretreatment processing procedure, the size of the crushed regenerated aluminum block is 0-70mm and more than 70mm, wherein the regenerated aluminum block with the size of more than 70mm is screened and then crushed again, and the regenerated aluminum block with the size of 0-70mm is screened and then divided into at least two size sections.

In the preheating treatment process and the melting casting process, at least two preheating furnaces, at least two smelting furnaces and at least two melting and holding furnaces are arranged in a matched manner; a distributor is arranged between the preheating furnaces and the smelting furnaces and is used for receiving the pure aluminum blocks of each preheating furnace and distributing the pure aluminum blocks to each smelting furnace; and a launder is arranged between the smelting furnaces and the melting and holding furnaces and is used for receiving the aluminum liquid of each smelting furnace and distributing the aluminum liquid to each melting and holding furnace.

The dust removal process is as follows: the workshop dust removal system comprises dust hoods arranged on the crushing and screening devices; the smoke dust removal system comprises smoke discharge pipelines arranged on the preheating furnace, the smelting furnace and the melting and maintaining furnace; wherein, dust excluding hood and exhaust pipe all are connected with dust collecting equipment.

A pre-storing process is arranged between the pre-treating process and the pre-heating process; the pre-storing process comprises the steps of arranging at least two bins, distributing the regenerated aluminum blocks after impurity removal into the bins through a conveying belt, unloading the materials from the bins, and conveying the materials into a preheating furnace.

The regenerated aluminum material blocks after impurity removal are lifted by the large-inclination-angle conveying belt and conveyed in a turning manner by the forward and reverse rotating conveying belt, so that the ingredient storage of each storage bin is realized.

In the pretreatment processing procedure, the aluminum waste is crushed by a double-shaft crusher and a hammer crusher, and simultaneously, iron is removed by arranging a magnetic roller, and finally, the regenerated aluminum blocks in different size sections are screened by a roller screen.

The double-shaft crusher is provided with an overload protection assembly, the torque of a cutter shaft is detected through a sensor, when the torque of the cutter shaft reaches a set peak value, the control system controls the cutter shaft to rotate reversely, and crushing operation is continued after material distribution is carried out again.

Hammer crusher is configured with control early warning subassembly, control early warning subassembly includes: carrying out data acquisition, monitoring and control on the rotating speed, load, thermal power, real-time power and feeding speed of a motor of the hammer crusher; and early warning or alarm is carried out on a software control system for equipment failure, oil pollution and overhaul early warning.

By adopting the technical scheme, the beneficial effects are as follows:

the whole structure of the aluminum alloy plate ingot production line is reasonable in design, the aluminum alloy plate ingot production line obtains the production process of aluminum alloy large plate ingot products through pretreatment processing, preheating processing, melting casting processing and matched dust removal environment-friendly equipment of regenerated aluminum alloy waste materials, realized waste aluminum materials, aluminum-containing waste materials, waste aluminum alloy materials such as extruded sections (door and window materials, curtain wall plate materials and the like), waste pop-top cans, waste aluminum radiators, waste lamp products, waste aluminum plates, waste domestic aluminum products, aluminum delayed pressing processing leftover materials and other waste aluminum recovery, melting and refining, the obtained aluminum alloy is recycled, the whole production process reduces production cost and increases income, energy is saved, aluminum burning loss is reduced, greenhouse gas and toxic gas environment-friendly standard emission is reduced, and aluminum alloy quality is improved. The recycling of aluminum is an important source for obtaining metal aluminum, and promotes the development of the field of recycled aluminum alloy in China.

Simultaneously, the overall structure design of this application can optimize the crushing and the sorting process of aluminum alloy waste material, improves other metal or non-metallic's sorting efficiency and effect, and through the setting of many sets of preheating processes and melting casting process, continuous uninterrupted operation has been realized simultaneously to improve production efficiency, reduced the idle time of part equipment, reduced energy consumption and manufacturing cost, promoted the further exploration and the development of the technology of secondary aluminium.

Drawings

FIG. 1 is a production process diagram of the present invention.

Detailed Description

The following detailed description of embodiments of the invention refers to the accompanying drawings.

Referring to fig. 1, the processing production process of the secondary aluminum comprises a pretreatment processing procedure, a preheating treatment procedure and a melting casting procedure; the pretreatment processing procedures are specifically as follows: recycled aluminum waste materials are conveyed to a feeding platform area of a plate chain conveyor from a material area by a forklift to cut binding aluminum wires of the packing materials, the packing materials are pushed to an inlet horizontal plate chain feeding area of a plate chain feeding machine by the forklift or a grabbing machine, the plate chain feeding machine is driven by a motor reducer, and the plate chain feeding machine has the characteristics of uniform belt speed, large bearing capacity, strong anti-impact capacity and the like, realizes low-position feeding, prevents slipping, prevents rolling and the like; the plate chain continuously conveys the aluminum waste to the upper end of the double-shaft crusher to enter a storage bin; the main machine of the double-shaft crusher comprises a box body, a movable cutter shaft, a fixed cutter frame, a bin, a No. 1 dust collection cover and a control system, wherein the movable cutter shaft is provided with two main shafts, the two main shafts are independently driven by a hydraulic motor direct reduction gear, each main shaft is provided with a plurality of special blades, the two main shafts rotate oppositely to bite aluminum waste materials and shred small materials with the material size of 200-400mm, the shredded materials fall into the upper bin of the No. 1 belt conveyor from the lower part of the cutter shaft, the control system is provided with an overload automatic protection function, if uncrushable materials or difficultly-shredded materials enter the bin, the cutter shaft automatically rotates reversely when the torque of the cutter shaft reaches a set peak value, the materials are kept for a plurality of seconds, the materials are forced to be redistributed and then rotate reversely to be crushed, and therefore the cutter shaft and the.

The 1# belt conveyor is driven by a motor reducer and conveys materials to an inlet bin of the hammer crushing all-in-one machine, the hammer crushing all-in-one machine consists of a bin, a collecting cover, a fixed frame, a rotor, a screen, a belt conveyer belt, a vibrating feeder, a magnetic roller, a 2# dust collecting cover and a control system, a hydraulic material pusher is arranged below the bin to realize uniform feeding and prevent material blockage, 4 groups of hammers are arranged on the rotor, a basket type lower screen is arranged below the rotor, the rotor is driven by the motor to tap, re-strike and finish grind the materials through centrifugal force, the crushed materials fall into the inner belt conveyer belt and are conveyed to an outlet vibrating feeder to realize forward uniform conveying of the materials, and an upper magnetic roller iron remover can be arranged at an outlet of the vibrating feeder to primarily separate iron materials from the materials; the control system monitors and collects the data of the rotating speed, load, thermal power and current power of the main motor, the speed and real-time position of the material pusher and the like, so as to realize the all-round monitoring and control of the crushing process and the state of the crusher; the motor is also provided with a safety protection setting, namely when a certain speed/torque is reached, the motor can automatically power off and stop, so that self-protection is realized; equipment failure, oil pollution, maintenance early warning and the like, and a software control system can perform early warning or alarm.

The materials crushed and separated by the hammer crusher fall into the plate chain conveyor, the materials are conveyed to the drum screen, the motor reducer drives the drum screen, the drum body slowly rotates, the materials move from the feeding side to the discharging side along the axial direction, the materials pass through the screen body device and fall out on the screen plate according to the particle size, and the residual materials are discharged from the discharge port of the drum body, so that the effect of screening the materials is achieved. Sorting out materials with the material sizes of 0-30mm, 30-70mm and more than 70mm to meet the feeding requirement of the next procedure; feeding the materials with the size of 0-30mm into a No. 2 belt conveyor, feeding the materials with the size of more than 30-70mm into a No. 3 belt conveyor, collecting the materials with the size of more than 70mm in a material box, and transferring the materials to the hammer type crushing all-in-one machine for crushing again;

the materials separated by the drum screen are conveyed to the 1# combined eddy current separator through the 2# belt conveyor and conveyed to the 2# combined eddy current separator through the 3# belt conveyor, and the combined eddy current separator adopts an eccentric magnetic pole technology, so that the nonmetal, ferromagnetic metal and nonferrous metal can be effectively and automatically separated, the labor force is reduced, the metal is efficiently recovered, and the yield value is increased. And respectively recovering the separated iron, nonferrous metal and nonmetal by a conveying belt to a charging basket.

A dust collecting cover is arranged above a bin of a double-shaft crusher, above a bin of a hammer crushing all-in-one machine and above a discharge port vibrating feeder, equipment such as a rotary screen and a combined eddy current separator is designed, and is collected to a dust removing system in a workshop through a negative pressure pipeline, the dust removing system comprises a multi-cone screen, a cyclone dust collector, a pulse bag filter and the like, air flow sucked in by the dust removing system firstly passes through the multi-cone screen to separate metal and large-piece materials, tiny metal particles in the very small material dust are separated and recovered, the tiny metal particles enter the cyclone dust collector after being filtered by the multi-cone screen, most of dust is collected and then is discharged into a large bag through a wheel valve to be treated, residues enter the pulse bag filter, the tiny particles are discharged through an air lock valve and collected into the large bag after being filtered, and clean air is discharged through a fan, to ensure the quality of the discharged air to reach the standard;

the pre-storing process comprises the following steps: the materials sorted by the 1# and 2# combined eddy current sorting machines are converged into the same parallel conveyer belt and conveyed to the horizontal section of the 1# large-inclination conveyer belt by the parallel conveyer belt, the large-inclination conveyer belt adopts a conveyer belt with wavy flanges and a transverse clapboard, the inclination angle is 0-90 degrees, the conveying capacity is large, the occupied area is small, the noise is low, and the conveying is stable; the material is conveyed to the high-altitude horizontal forward and reverse rotating conveyor belt through the 1# large-inclination-angle conveyor belt, and is conveyed to the 1# bin or the 2# bin through the horizontal forward and reverse rotating conveyor belt to be temporarily stored (two bins are adopted in the method, more bins can be arranged according to actual requirements, and at the moment, more bins can be prepared by arranging the multistage forward and reverse rotating conveyor belt), so that the aim of storing different alloy materials in a classified mode can be achieved, continuous operation can be achieved, and the problem that part of equipment is idle for too long time is avoided; according to the multi-arm unloading machine, the horizontal discharge ports are designed oppositely, continuous uniform unloading and accurate flow regulation are realized through the same walking multi-arm unloading machine, material blockage is avoided, and the problem of poor material flowability is solved; the multi-arm unloader is characterized by a plurality of crab-leg-shaped unloading arms, materials can be respectively and gradually scraped from outlets of storage bins at two sides and pushed to a discharge port, the unloading arms sequentially travel and gradually penetrate into the lower parts of the storage bins, the materials are rotatably drawn, and the materials at the bottom of the storage bins are naturally and additionally drawn; therefore, large-particle materials can be output in a controlled mode at an ordered speed, and the uniformity of material output is ensured.

The preheating treatment process comprises the following steps: the discharging machine uniformly conveys the materials to the horizontal section of the 2# large-inclination-angle conveying belt below the discharging machine; promote the material to the high altitude discharge gate through 2# big inclination conveyer belt, a discharge gate configuration vibrating feeder realizes even unloading, the adjustable division board reposition of redundant personnel of vibrating feeder discharge gate top configuration, the material after the reposition of redundant personnel is through 1# or 2# horizontal weighing conveyer belt, through 1# weighing conveyer belt 1# preheating furnace entry is carried to the material, through 2# weighing conveyer belt 2# preheating furnace entry is carried to the material.

The preheating furnace is mainly used for preheating crushed materials, removing paint on the surface, removing films, burning waste gas again and the like, and the equipment mainly comprises a combustion system, a heating furnace, a rotary preheating furnace, an electric control system and other main parts; the natural gas combustion heating is adopted, materials firstly enter a feeding air lock of a rotary preheating furnace from a weighing conveyer belt, the feeding air lock controls blanking, the materials enter a pipeline after passing through the air lock and are inserted into a horizontally placed rotary preheating furnace drying cylinder, a chain wheel is directly connected with a motor speed reducer to drive a drying cylinder outer wall chain to rotate, a spiral groove is designed on an inner side furnace wall of the drying cylinder, the materials fall into the spiral groove, a hot gas heating pipeline is designed in the middle of the drying cylinder, the tail part of the heating furnace pipeline is communicated with the tail part of the drying cylinder, the heating pipeline performs radiation preheating on the materials in the drying cylinder, the drying cylinder rotates to push the materials to be conveyed forwards, a discharging air lock is designed at the tail end of the drying cylinder, the materials enter a hot material conveyor from the discharging air lock, smoke generated after combustion of organic matters such as a material paint film and the like in the drying cylinder flows from the tail end, and the waste gas enters a circulating fan after passing through a cyclone dust collector, so that the waste gas is combusted again.

Waste gas generated by the heating furnace enters the heat exchanger through the adjustable valve to heat cold air, and heated air enters the combustion system through the combustion fan, so that energy consumption is saved, and the waste gas passing through the heat exchanger enters; enters a pipeline of a dust removal system and leads to a dust removal system outside the workshop.

The material temperature of a discharge port after being treated by the preheating furnace is up to 300 ℃, the hot material treated by the 1# preheating furnace enters a 1# hot material conveyor, the hot material treated by the 2# preheating furnace enters a 2# hot material conveyor, the hot material conveyor adopts a phosphorus plate chain, a roller sliding rail structure, a sealing cover is arranged above the phosphorus plate chain and driven by a motor reducer, and the device has the characteristics of uniform speed, large bearing capacity, high temperature resistance, strong impact resistance and the like, realizes low-level feeding, prevents slipping, prevents rolling and the like; the hot material conveyer carries a big vibration feed branch material sieve to the hot material after the preheater is handled, and the hot material falls on vibrating feeder, even feed, vibrating feeder sets up two exports, one on one side, and the branch material baffle is hung to the top, realizes that the material is single to be carried 1# double-chamber stove or 2# double-chamber stove, perhaps carries two double-chamber stoves simultaneously, and the smelting furnace in this embodiment adopts double-chamber stove.

A melting and casting process: the double-chamber furnace is provided with two hearths, a large hearth and a small hearth, a vortex well is arranged outside the small hearth, a partition wall is arranged between the two hearths, heat can be heated through holes formed in the wall, materials fall into the vortex well to be rapidly melted and circularly enter the small hearth through a mechanical pump, and the two hearths can be both opened to be added with aluminum extension processing leftover materials, so that liquid aluminum liquid is rapidly melted; the two double-chamber furnaces introduce the molten aluminum into a No. 1 melting and retaining furnace or a No. 2 melting and retaining furnace through launders, the maximum aluminum liquid amount of the melting and retaining furnace is 90T, and a large aluminum ingot stub bar or aluminum raw materials can be added through a furnace door for quick melting, and slagging off, refining, heat preservation, alloy proportioning and the like are realized; the double-chamber furnace and the melting and holding furnace are both matched with corresponding flue gas recovery pipelines which are communicated with outdoor flue gas dust removal equipment, and the flue gas dust removal equipment is treated by a dust removal system to reach the environmental protection emission standard; after the alloy proportion in the melting and holding furnace is qualified, the alloy is guided into a casting machine through a launder, an online degassing device and the like to cast large aluminum plate ingots, and 5 large aluminum plate ingots can be produced at most by casting once. And conveying the large plate ingot finished product to other branch plants of the company for hot continuous rolling, cold rolling and the like, thereby realizing the recycling of the two-raw aluminum and the aluminum alloy.

The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are merely illustrative of the principles of the invention, but that various changes and modifications may be made without departing from the spirit and scope of the invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. A processing and producing process for secondary aluminum is characterized by comprising a pretreatment processing procedure, a preheating treatment procedure and a melting and casting procedure; wherein:

the pretreatment processing procedure comprises the steps of crushing the aluminum waste to form a regenerated aluminum material block, and screening to obtain regenerated aluminum material blocks with different sizes in different sections; respectively conveying the regenerated aluminum blocks of all the size sections to corresponding eddy current separators to remove impurities;

the preheating treatment process comprises the steps of weighing the regenerated aluminum material block after impurity removal, conveying the regenerated aluminum material block into a preheating furnace, and carrying out preheating, surface depainting, stripping and waste gas treatment on the regenerated aluminum material block to obtain a pure aluminum material block;

the melting casting process is to convey the pure aluminum material block to a melting furnace for melting, convey the pure aluminum material block to a melting and holding furnace, refine and allocate the alloy grade, and cast the large aluminum plate ingot by a casting machine after the allocation ratio is detected to be qualified;

a pre-storing process is arranged between the pre-treating process and the pre-heating process; the pre-storing process comprises at least two material bins which are arranged, wherein the regenerated aluminum material blocks after impurity removal are lifted by a large-inclination-angle conveying belt and are conveyed in a turning manner by a forward and reverse rotating conveying belt, so that the burdening storage of each material bin is realized, and the material is unloaded from each material bin and is conveyed to a preheating furnace;

2. The secondary aluminum processing and producing process as claimed in claim 1, wherein in the pretreatment process, the size of the crushed secondary aluminum blocks is 0-70mm and more than 70mm, wherein the secondary aluminum blocks with the size of more than 70mm are sieved and crushed again, and the secondary aluminum blocks with the size of 0-70mm are sieved and divided into at least two size sections.

3. The secondary aluminum processing production process according to claim 1, further comprising a dust removal process, wherein the dust removal process is:

the workshop dust removal system comprises dust hoods arranged on the crushing and screening devices;

the smoke dust removal system comprises smoke discharge pipelines arranged on the preheating furnace, the smelting furnace and the melting and maintaining furnace;

wherein, dust excluding hood and exhaust pipe all are connected with dust collecting equipment.

4. The secondary aluminum processing and producing process as claimed in claim 1, wherein in the pretreatment process, the aluminum scrap is crushed by a double-shaft crusher and a hammer crusher, and iron is removed by a magnetic roller, and finally the secondary aluminum lumps in different size sections are screened by a roller screen.

5. The secondary aluminum processing and producing process as claimed in claim 4, wherein the double-shaft crusher is provided with an overload protection assembly, the torque of the cutter shaft is detected through a sensor, when the torque of the cutter shaft reaches a set peak value, the control system controls the cutter shaft to reversely rotate, and the crushing operation is continued after the material is distributed again.

6. A secondary aluminium processing and producing process according to claim 5, wherein the hammer crusher is provided with a monitoring and pre-warning assembly, the monitoring and pre-warning assembly comprising:

carrying out data acquisition, monitoring and control on the rotating speed, load, thermal power, real-time power and feeding speed of a motor of the hammer crusher;

and early warning or alarm is carried out on a software control system for equipment failure, oil pollution and overhaul early warning.