Copper slag waste heat recovery system and waste heat recovery method thereof

Abstract

The invention belongs to the technical field of slag waste heat recovery and comprehensive utilization, and particularly relates to a copper slag waste heat recovery system and a waste heat recovery method thereof. Comprising a slag ladle, a granulating bin is arranged at a slag outlet of the slag ladle, a spray gun is arranged in the granulating bin, and a revolving cup device is arranged on the spray gun; an outlet of the granulation bin is connected with a boiler, the boiler is connected with a waste heat boiler and a pyrolysis gasification furnace, and the boiler is connected with the waste heat boiler and the pyrolysis gasification furnace; the waste heat boiler is connected with power generation equipment, low-pressure steam generated after power generation of the power generation equipment is used for heating the user heat storage device, and condensate water generated by heating of the user heat storage device enters the boiler. The first hot air in the granulation bin enters the waste heat boiler, and superheated steam generated by the boiler enters the power generation equipment. The granulation method combining gas quenching and centrifugation is adopted, high-temperature gas and superheated steam at different temperatures are obtained through air and water cooling in different environments, the high-temperature gas and the superheated steam are specifically applied to a pyrolysis gasification furnace and a waste heat boiler, and efficient utilization of copper slag waste heat is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of slag waste heat recovery and comprehensive utilization, and in particular relates to a copper slag waste heat recovery system and a waste heat recovery method. Background Art

[0002] The pyrometallurgical copper smelting process is the process of converting copper sulfide concentrate into electrolytic copper through matte smelting, blowing, pyrometallurgical refining, electrolytic refining and other links. High-temperature copper slag mainly refers to the slag produced in the process of matte smelting, copper matte blowing and crude copper refining. The copper slag is mainly composed of fayalite, magnetite, copper sulfide, metallic copper and some gangue, in which the content of iron and copper is about 40% and 2% to 8% respectively.

[0003] The pyrometallurgical copper smelting process produces about 2.2 tons of copper slag for every ton of copper produced. The temperature of the copper slag out of the furnace is about 1200℃~1300℃, and each ton of copper slag contains about 1.13GJ of heat. However, the waste heat of high-temperature copper slag in pyrometallurgical copper smelting enterprises has basically not been recycled. The recycling of waste heat from high-temperature copper slag can not only reduce the energy consumption of copper smelting enterprises, but also reduce pollutant emissions and alleviate environmental pressure. It plays a vital role in energy conservation and emission reduction of enterprises. The technology of waste heat recovery and utilization of high-temperature copper slag needs more in-depth research.

[0004] The current copper slag treatment process adopts the method of slow cooling of slag bags, the main purpose of which is to make the copper slag form a better crystal form during the cooling process, so as to facilitate the subsequent mineral processing process to better recover copper. However, the slow cooling process of the slag bag makes it difficult to utilize the waste heat of the high-temperature copper slag, which not only causes a large amount of waste heat waste, but also forms salt scale attached to the pipes and slag bags due to the evaporation of spray wastewater, resulting in serious corrosion and loss, greatly reducing the cooling efficiency, interfering with production, and increasing the difficulty of subsequent resource utilization of copper slag. Summary of the invention

[0005] In order to solve the above problems, the present invention provides a copper slag waste heat recovery system and a waste heat recovery method. The mutual combination and effective connection of the recyclable energy processing system and the production system are realized. The granulation bin adopts a granulation method combining gas quenching and centrifugation, which has the characteristics of high operation safety and high recovery rate. Through air and water cooling in different environments, high-temperature gases and superheated steam of different temperatures are obtained, which are targeted for use in pyrolysis gasification furnaces and waste heat boilers. It not only solves the serious problem of resource waste, but also effectively realizes the efficient utilization of copper slag waste heat. After the waste heat recovery of this system, the high-temperature copper slag with an original temperature of about 1200℃ to 1400℃ becomes low-temperature slag particles with a temperature of about 80℃ to 150℃. The waste heat recovery effect is obvious and provides convenience for the subsequent flotation process.

[0006] The present invention solves the above technical problems through the following technical solutions.

[0007] One of the purposes of the present invention is to provide a copper slag waste heat recovery system, comprising a slag ladle, a granulation bin is provided at the slag outlet of the slag ladle, a spray gun is provided in the granulation bin below the slag outlet, a rotating cup device is provided on the spray gun, the rotating cup device is used to centrifuge, crush and granulate the copper slag, and the spray gun is used to air-cool and granulate the copper slag, and heat exchange to form a first hot air;

[0008] The outlet of the granulation bin is connected to a fixed bed boiler, which is connected to a waste heat boiler and a pyrolysis gasification furnace. The fixed bed boiler is used to perform heat exchange on the copper slag to generate second hot air after heat exchange;

[0009] The waste heat boiler is connected to a power generation device, the first hot air and the second hot air enter the waste heat boiler to exchange heat with the waste heat boiler to form a first superheated steam, and the first superheated steam enters the power generation device to generate electricity for the power generation device;

[0010] The low-pressure steam generated by the power generation equipment after power generation is used to heat the user's heat storage device for heating. The condensed water generated by the user's heat storage device for heating enters the fixed bed boiler and is used by the fixed bed boiler to perform heat exchange on the copper slag to generate the second superheated steam. The second superheated steam enters the power generation equipment and is used by the power generation equipment to generate electricity.

[0011] The copper slag in the slag bag is circulated through the granulation bin, fixed bed boiler and waste heat boiler to achieve waste heat recovery of the copper slag.

[0012] Preferably, in the copper slag waste heat recovery system, the spray gun is a gas spray gun, one end of the gas spray gun is connected to an air compressor via a first air pipe, and the first air pipe is provided with a first solenoid valve.

[0013] Preferably, in the above-mentioned copper slag waste heat recovery system, the fixed bed boiler adopts two heat exchange methods, water cooling and air cooling, wherein air cooling is connected to an air compressor through an air pipe, and cold air is provided by the air compressor to enter the fixed bed boiler, and the second hot air is formed through heat exchange in the fixed bed boiler; water cooling is that condensed water generated by heating of the user's heat storage device enters the fixed bed boiler through a drain pipe, and the second superheated steam is formed through heat exchange in the fixed bed boiler.

[0014] Preferably, in the above-mentioned copper slag waste heat recovery system, the granulation bin is provided with an exhaust hole, the exhaust hole is connected to the waste heat boiler through a first hot air exhaust pipe, the waste heat boiler is connected to the power generation equipment through a second hot air exhaust pipe, and the first hot air exhaust pipe is provided with a second solenoid valve.

[0015] Preferably, in the above copper slag waste heat recovery system, the fixed bed boiler is provided with a third hot air exhaust pipe, the third hot air exhaust pipe is connected to the first hot air exhaust pipe, and the third hot air exhaust pipe is provided with a third solenoid valve.

[0016] Preferably, in the above-mentioned copper slag waste heat recovery system, the three hot air exhaust pipes are connected to a connecting pipe, the connecting pipe is connected to a pyrolysis gasification furnace, the second hot air enters the pyrolysis gasification furnace, and is used for pyrolysis reaction in the pyrolysis gasification furnace, a fourth solenoid valve is provided on the connecting pipe, and the pyrolysis gasification furnace is provided with a first exhaust pipe, and the first exhaust pipe is connected to the three hot air exhaust pipes.

[0017] Preferably, in the copper slag waste heat recovery system, the fixed bed boiler is provided with a superheated steam exhaust pipe, the superheated steam exhaust pipe is connected to the power generation equipment, and a fifth solenoid valve is provided on the superheated steam exhaust pipe.

[0018] Preferably, in the above copper slag waste heat recovery system, the discharge outlet of the fixed bed boiler is connected to a flotation recovery device.

[0019] The second object of the present invention is to provide a method for recovering waste heat from copper slag using the above-mentioned waste heat recovery system for copper slag, comprising the following steps:

[0020] The copper slag in the slag bag is discharged from the slag outlet into the granulation bin. At this time, the temperature of the copper slag is 1200℃~1400℃. The copper slag enters the rotary cup device, which centrifuges, crushes and granulates the copper slag. At the same time, the cold air of the spray gun further crushes, granulates and exchanges heat with the copper slag, and falls into the bottom of the granulation bin, where it is cooled to 1000℃~1100℃ and enters the fixed bed boiler.

[0021] The cold air from the spray gun cools the copper slag and exchanges heat with it, forming the first hot air that enters the waste heat boiler;

[0022] After the fixed bed boiler exchanges heat with the copper slag, the second hot air with a temperature of 600°C to 800°C is generated and enters the waste heat boiler and the pyrolysis gasification furnace. At the same time, the condensed water generated by the user's heat storage device for heating enters the fixed bed boiler to exchange heat with the copper slag to generate the second superheated steam, which enters the power generation equipment.

[0023] The combustible gas generated by the pyrolysis gasification furnace and the second hot air generated by the fixed bed boiler after the copper slag is heat-exchanged heats the water in the waste heat boiler to form the first superheated steam which enters the power generation equipment. The power generation equipment generates electricity through the first superheated steam and the second superheated steam and provides electric energy to the user. The low-pressure steam generated by the power generation equipment after generating electricity is used to heat the user's heat storage device for heating. The condensed water generated by the heating enters the fixed bed boiler for heat exchange to generate the second superheated steam, thus forming a heat exchange cycle.

[0024] The fixed bed boiler cools the copper slag to 80℃~150℃ through heat exchange and then discharges it for flotation process, realizing waste heat recovery and resource utilization of copper slag.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] The present invention proposes a copper slag waste heat recovery system, which realizes the mutual combination and effective connection of the recyclable energy processing system and the production system. The granulation bin adopts a granulation method combining gas quenching and centrifugation, which has the characteristics of high operation safety and high recovery rate. Through air and water cooling in different environments, high-temperature gases and superheated steam of different temperatures are obtained, which are targetedly applied to pyrolysis gasification furnaces and waste heat boilers, which not only solves the serious problem of resource waste, but also effectively realizes the efficient utilization of copper slag waste heat. After the waste heat recovery of this system, the high-temperature copper slag with an original temperature of about 1200℃~1400℃ is transformed into low-temperature slag particles with a temperature of about 80℃~150℃. The waste heat recovery effect is obvious and provides convenience for the subsequent flotation process. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the overall structure of the copper slag waste heat recovery system of the present invention.

[0029] 1-slag bag, 2-slag outlet, 3-granulation bin, 4-spray gun, 5-rotor device, 6-fixed bed boiler, 7-air compressor, 8-waste heat boiler, 9-pyrolysis gasification furnace, 10-power generation equipment, V1-first solenoid valve, V2-second solenoid valve, V3-third solenoid valve, V4-fourth solenoid valve, V5-fifth solenoid valve, V6-sixth solenoid valve, V7-seventh solenoid valve, V8-eighth solenoid valve, V9-ninth solenoid valve. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] It should be noted that the professional terms used in the present invention are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of the present invention. Certain words are used in the present invention to refer to specific components. Those skilled in the art should understand that technicians will use different nouns to refer to the same component. The present invention does not distinguish between components by the difference in nouns, but by the difference in the functions of the components. As mentioned throughout the specification and claims, "including" is an open term and should be understood as "including but not limited to".

[0032] The current copper slag treatment process adopts the method of slow cooling of slag bags, the main purpose of which is to make the copper slag form a better crystal form during the cooling process, so as to facilitate the subsequent mineral processing process to better recover copper. However, the slow cooling process of the slag bag makes it difficult to utilize the waste heat of the high-temperature copper slag, which not only causes a large amount of waste heat waste, but also forms salt scale attached to the pipes and slag bags due to the evaporation of spray wastewater, resulting in serious corrosion and loss, greatly reducing the cooling efficiency, interfering with production, and increasing the difficulty of subsequent resource utilization of copper slag.

[0033] Based on the above problems, the present invention provides a copper slag waste heat recovery system, such as Figure 1 As shown, it includes a slag bag 1, a granulation bin 3 is provided at the slag outlet 2 of the slag bag 1, a spray gun 4 is provided in the granulation bin 3 below the slag outlet 2, and a rotating cup device 5 is provided on the spray gun 4. The rotating cup device 5 is used to centrifuge, crush and granulate the copper slag, and the spray gun 4 is used to air-cool and granulate the copper slag, and to form a first hot air by heat exchange; the outlet of the granulation bin 3 is connected to a fixed bed boiler 6, and the fixed bed boiler 6 is connected to a waste heat boiler 8 and a pyrolysis gasification furnace 9. The fixed bed boiler 6 is used to perform heat exchange on the copper slag to generate a second hot air after heat exchange; the waste heat boiler 8 is connected to a power generation device 10, and the first hot air and The second hot air enters the waste heat boiler 8, and is used for heat exchange with the waste heat boiler 8 to form the first superheated steam. The first superheated steam enters the power generation equipment 10, and is used for the power generation equipment 1 to generate electricity. The low-pressure steam generated by the power generation equipment 10 after generating electricity is used to heat the user's heat storage device for heating. The condensed water generated by the user's heat storage device for heating enters the fixed bed boiler 6, and is used by the fixed bed boiler 6 to perform heat exchange with the copper slag to generate the second superheated steam. The second superheated steam enters the power generation equipment 10, and is used for the power generation equipment 10 to generate electricity. The copper slag in the slag bag 1 is subjected to a heat exchange cycle through the granulation bin 3, the fixed bed boiler 6 and the waste heat boiler 8 to realize the recovery of the waste heat of the copper slag.

[0034] Among them, the spray gun 4 surrounds the outside of the rotary cup device 5, and the spray gun 4 and the rotary cup device 5 are both located directly below the slag outlet 2. When the copper slag enters the granulation bin 3 through the slag outlet 2, the copper slag enters the rotary cup device 5, and the copper slag flowing into the slag outlet 2 is centrifuged, crushed and granulated. At the same time, the spray gun 4 air-cools the copper slag and further crushes and granulates it. The cold air is heated by the copper slag to form the first hot air, which is discharged from the granulation bin into the waste heat boiler 8.

[0035] The cold air from the spray gun 4 further crushes, granulates and exchanges heat for the copper slag, which falls into the bottom of the granulation bin 3 and is discharged into the fixed bed boiler 6 through the granulation bin 3. The fixed bed boiler 6 exchanges heat with the copper slag. The heat exchange methods include air cooling and water cooling. The second hot air generated by air cooling enters the waste heat boiler 8 and the pyrolysis gasifier 9, and the first superheated steam generated by water cooling enters the power generation equipment 10. At the same time, the pyrolysis gasifier 9 can generate combustible gas after reaction, which can be further recycled. The hot air generated by the combustible gas enters the waste heat boiler 8 for heat exchange. The electric energy generated by the power generation equipment 10 is transmitted to the user through the wire to provide electric energy for the user, and the low-pressure steam generated by the power generation equipment 10 after power generation is used to heat the user's heat storage device. The condensed water generated by the user's heat storage device heating enters the fixed bed boiler 6 and is used for the fixed bed boiler 6 to exchange heat with the copper slag. This can realize the combination of the recyclable energy processing system and the production system, and has a high-temperature copper slag waste heat recovery system with high operation safety and high recovery rate.

[0036] The present invention proposes a copper slag waste heat recovery system, which realizes the mutual combination and effective connection of the recyclable energy processing system and the production system. The granulation bin adopts a granulation method combining gas quenching and centrifugation, which has the characteristics of high operation safety and high recovery rate. Through air and water cooling in different environments, high-temperature gases and superheated steam of different temperatures are obtained, which are specifically applied to pyrolysis gasification furnaces and waste heat boilers, which not only solves the serious problem of resource waste, but also effectively realizes the efficient utilization of copper slag waste heat.

[0037] The invention is further described below through specific examples.

[0038] Example

[0039] The present invention provides a copper slag waste heat recovery system, such as Figure 1As shown, it includes a slag bag 1, a granulation bin 3 is provided at the slag outlet 2 of the slag bag 1, a spray gun 4 is provided in the granulation bin 3 below the slag outlet 2, and a rotating cup device 5 is provided on the spray gun 4. The rotating cup device 5 is used to centrifuge, crush and granulate the copper slag, and the spray gun 4 is used to air-cool and granulate the copper slag, and to form a first hot air by heat exchange; the outlet of the granulation bin 3 is connected to a fixed bed boiler 6, and the fixed bed boiler 6 is connected to a waste heat boiler 8 and a pyrolysis gasification furnace 9. The fixed bed boiler 6 is used to perform heat exchange on the copper slag to generate a second hot air after heat exchange; the waste heat boiler 8 is connected to a power generation device 10, and the first hot air and The second hot air enters the waste heat boiler 8, and is used for heat exchange with the waste heat boiler 8 to form the first superheated steam. The first superheated steam enters the power generation equipment 10, and is used for the power generation equipment 1 to generate electricity. The low-pressure steam generated by the power generation equipment 10 after generating electricity is used to heat the user's heat storage device for heating. The condensed water generated by the user's heat storage device for heating enters the fixed bed boiler 6, and is used by the fixed bed boiler 6 to perform heat exchange with the copper slag to generate the second superheated steam. The second superheated steam enters the power generation equipment 10, and is used for the power generation equipment 10 to generate electricity. The copper slag in the slag bag 1 is subjected to a heat exchange cycle through the granulation bin 3, the fixed bed boiler 6 and the waste heat boiler 8 to realize the recovery of the waste heat of the copper slag.

[0040] The granulation bin 3 is made of high temperature resistant and corrosion resistant materials, and a slag inlet is provided on the top thereof for receiving high temperature copper slag from the smelting process. Inside the granulation bin, near the slag inlet, a rotating cup device and one or more rows of gas spray guns are installed to ensure that the high temperature copper slag can be subjected to the centrifugal effect of the rotating cup and the impact of the high-speed airflow after entering the granulation bin, so as to achieve cooling and granulation. A slag outlet is provided at the bottom of the granulation bin, and the granulated copper slag is smoothly discharged through a suitable tilt angle and a vibration device.

[0041] The fixed bed boiler 6 is used as a system heat exchange device. Its slag particle inlet is connected to the slag particle outlet of the granulation bin 3 to receive the copper slag that has been gas-quenched and granulated. An efficient heat exchange surface is provided inside the fixed bed boiler 6 to absorb the residual heat in the copper slag. The boiler is provided with a hot gas output end and a cold gas input end. The cold gas input end is provided at the bottom of the fixed bed boiler 6 to fully exchange heat; the hot gas output end is directly connected to the waste heat boiler 8 and the pyrolysis gasification furnace 9 to transfer high-temperature hot gas to realize the recycling of hot gas and improve energy utilization. In addition, the fixed bed boiler 6 is also provided with a steam output end, which is connected to the generator set 5 for power generation.

[0042] The waste heat boiler 8 receives high-temperature hot gas from the granulation bin 3 and the fixed bed boiler 6, and converts the heat energy in the hot gas into steam through the internal heat exchange tube bundle. The design of the waste heat boiler 8 should fully consider the thermal efficiency to ensure that as much heat energy as possible is converted into steam. The steam output end of the waste heat boiler 8 is connected to the generator set 5 to provide power for power generation.

[0043] The pyrolysis gasification furnace 7 is an advanced thermochemical conversion device integrated into the entire waste heat recovery system. The device uses a high-temperature heat source to pyrolyze and gasify organic matter or specific materials to generate combustible gas or other high value-added products.

[0044] The generator set 10 adopts a steam turbine or a steam turbine-generator combined cycle mode, receives steam from the waste heat boiler 8 and the fixed bed boiler 6, and drives the generator to generate electricity. The selection of the generator set 10 should be optimized according to the overall thermal efficiency and power demand of the system.

[0045] In a specific embodiment, the spray gun 4 is a gas spray gun, one end of which is connected to an air compressor 7 through a first air pipe, and a first electromagnetic valve V1 is provided on the first air pipe. The flow rate of cold air entering the spray gun 4 can be regulated by the first electromagnetic valve V1, and the particle size of the further broken particles and the temperature of the heat exchange can be controlled. The granulation bin 3 adopts a granulation method combining gas quenching and centrifugation, which has the characteristics of high operation safety and high recovery rate.

[0046] In a specific embodiment, the cup device 5 includes a granulator, and the cup device 5 centrifuges, crushes and granulates the copper slag flowing into the slag outlet 2. When the liquid slag flows from the top into the center of the high-speed rotating granulator in the cup device 5 and spreads on the surface of the granulator to form a liquid film, as the granulator rotates, the slag liquid film gradually advances to the edge of the granulator under the action of centrifugal force, the speed gradually increases, and the thickness of the liquid film gradually decreases. After the slag moves to the outer edge of the granulator, the wall of the granulator no longer has a restraining effect on it. At this time, the liquid slag is crushed under the influence of centrifugal force, surface tension, and gas-liquid interaction, and finally forms fine droplets. At the same time, the spray gun 4 air-cools the copper slag and further crushes and granulates it. The cold air is heated by the copper slag to form the first hot air, which is discharged from the granulation bin into the waste heat boiler 8.

[0047] In a specific embodiment, the fixed bed boiler 6 adopts water cooling and air cooling. The air cooling is connected to the air compressor 7 through an air pipe, and the cold air provided by the air compressor 7 enters the fixed bed boiler 6, and the fixed bed boiler 6 forms the second hot air through heat exchange; the water cooling is that the condensed water generated by the user's heat storage device for heating enters the fixed bed boiler 6 through the drain pipe, and forms the second superheated steam through heat exchange of the fixed bed boiler 6. The seventh solenoid valve V7 is provided on the air pipe, and the eighth solenoid valve V8 is provided on the drain pipe. In addition to providing cold air for the spray gun 4, the air compressor 7 also provides cold air for the fixed bed boiler 6 through the air pipe. The flow rate of cold air in the air pipe is controlled by the seventh solenoid valve V7, thereby controlling the air-cooling heat exchange flow rate of the fixed bed boiler 6; water cooling is the condensed water generated by the user's heat storage device for heating and heating entering the fixed bed boiler 6 through the drain pipe. After the condensed water performs heat exchange with the fixed bed boiler 6, the fixed bed boiler 6 is provided with a second superheated steam exhaust pipe, and the second superheated steam exhaust pipe is connected to the power generation equipment 10. The fixed bed boiler 6 generates second superheated steam by heat exchange with the copper slag. The second superheated steam is discharged into the power generation equipment 10 through the superheated steam exhaust pipe. The superheated steam exhaust pipe is provided with a fifth solenoid valve V5 for controlling the flow rate of superheated steam in the superheated steam exhaust pipe.

[0048] In a specific embodiment, the granulation bin 3 is provided with an exhaust hole, which is connected to the waste heat boiler 8 through a first hot air exhaust pipe, and the waste heat boiler 8 is connected to the power generation equipment 10 through a second hot air exhaust pipe, and a second electromagnetic valve V2 is provided on the first hot air exhaust pipe. When cold air enters the granulation bin 3 through the spray gun 4, that is, during the air cooling and further crushing and granulation of the copper slag, the cold air and the copper slag are heat exchanged, and the crushed and granulated copper slag falls into the bottom of the granulation bin 3. The exhaust hole is set on the upper wall of the granulation bin 3, and the first hot air generated by the heat exchange enters the second hot air exhaust pipe through the exhaust hole, and the flow rate of the first hot air discharged into the waste heat boiler 8 is controlled by the electromagnetic valve V2; the first hot air heats the waste heat boiler 8, and the waste heat boiler 8 is transferred to water through heat exchange to generate steam. After steam-water separation, the steam enters the superheater and is heated again to become the first superheated steam, which is discharged into the power generation equipment 10 through the second hot air exhaust pipe. The second hot air exhaust pipe is provided with a sixth electromagnetic valve V6 for controlling the flow rate of the first superheated steam in the second hot air exhaust pipe. The first superheated steam generated by the water heat exchange in the waste heat boiler 8 is saturated steam. The power generation equipment 10 is a steam power generation equipment. The first superheated steam realizes the conversion of thermal energy into mechanical energy through the steam turbine, thereby driving the generator to rotate and generate electrical energy. The low-pressure steam generated by the power generation equipment 10 after power generation is discharged into the user's heat storage device through the low-pressure steam pipe, which is used to heat the user's heat storage device. A ninth solenoid valve V9 is provided on the low-pressure steam pipe, and the ninth solenoid valve V9 is used to control the flow rate of the low-pressure steam.

[0049] In a specific embodiment, the fixed bed boiler 6 is provided with a third hot air exhaust pipe, the third hot air exhaust pipe is connected to the first hot air exhaust pipe, the third hot air exhaust pipe is provided with a third solenoid valve V3, the third hot air exhaust pipe is connected to a connecting pipe, the connecting pipe is connected to the pyrolysis gasification furnace 9, the second hot air enters the pyrolysis gasification furnace 9, and is used for the pyrolysis gasification furnace 9 to perform pyrolysis reaction, the connecting pipe is provided with a fourth solenoid valve V4, the pyrolysis gasification furnace 9 is provided with a first exhaust pipe, and the first exhaust pipe is connected to the three hot air exhaust pipes. The third hot air exhaust pipe is arranged on the upper end wall of the fixed bed boiler 6, and the outlet end of the third hot air exhaust pipe is connected to the first hot air exhaust pipe. The third hot air exhaust pipe is provided with a third solenoid valve V3, and the third solenoid valve V3 is used to control the flow rate of hot air discharged from the third hot air exhaust pipe into the waste heat boiler 8; the third hot air exhaust pipe is connected to the pyrolysis gasification furnace 9 through a connecting pipe, and the first hot air is discharged into the pyrolysis gasification furnace 9 through the connecting pipe. The pyrolysis gasification furnace can generate combustible gas after the reaction, which can be further recycled and utilized. The generated hot air can enter the third hot air exhaust pipe through the exhaust pipe, and then be discharged into the waste heat boiler 8 for utilization. The connecting pipe is provided with a fourth solenoid valve V4, and the flow rate of the first hot air entering the pyrolysis gasification furnace 9 is controlled by the fourth solenoid valve V4.

[0050] In a specific embodiment, the discharge port of the fixed bed boiler 6 is connected to a flotation recovery device 11. The flotation recovery device 11 is designed to receive and process the slag particles discharged from the fixed bed boiler 6. The flotation recovery device 11 utilizes the flotation principle to effectively separate useful minerals from gangue minerals by adding specific flotation agents and adjusting the pH value of the slurry, thereby realizing the recovery of valuable metals. During the flotation process, useful minerals are separated from gangue minerals due to differences in surface physical and chemical properties to form a concentrate foam layer. After these concentrate foam layers are collected, dehydrated and other post-processing processes, concentrate products containing high-grade valuable metals can be obtained, and the remaining tailings can be further processed or safely disposed of.

[0051] The method for recovering waste heat from copper slag using the above-mentioned waste heat recovery system for copper slag comprises the following steps:

[0052] S1. The copper slag in the slag bag 1 is discharged from the slag outlet 2 into the granulation bin 3. At this time, the temperature of the copper slag is 120°C to 1400°C. The copper slag enters the rotary cup device 5, which centrifugally granulates, crushes and granulates the copper slag. At the same time, the cold air from the spray gun 4 further crushes and granulates the copper slag, falls into the bottom of the granulation bin 3, and is cooled to 1000°C to 1100°C before entering the fixed bed boiler 6.

[0053] S2, the cold air from the spray gun 4 cools the copper slag for heat exchange, forming the first hot air which enters the waste heat boiler 8.

[0054] S3. After the fixed bed boiler 6 performs heat exchange on the copper slag, the second hot air with a temperature of 600°C to 800°C is generated, which enters the waste heat boiler 8 and the pyrolysis gasification furnace 9. At the same time, the condensed water generated by the user's heat storage device for heating enters the fixed bed boiler 6 to perform heat exchange on the copper slag, generating the second superheated steam, which enters the power generation equipment 10.

[0055] S4, the combustible gas generated by the pyrolysis gasification furnace 9 and the second air generated by the heat after the fixed bed boiler 6 exchanges heat with the copper slag heats the water in the waste heat boiler 8 to form a first superheated steam which enters the power generation equipment 10. The power generation equipment 10 generates electricity through the first superheated steam and the second superheated steam and provides electric energy to the user. At the same time, the low-pressure steam generated by the power generation equipment 10 after generating electricity is used to heat the user's heat storage device for heating. The condensed water generated by the heating enters the fixed bed boiler 6 for heat exchange to generate a second superheated steam, forming a heat exchange cycle.

[0056] S5 and the fixed bed boiler 6 cool the copper slag to 80°C to 150°C through heat exchange and then discharge it for flotation process, thereby realizing waste heat recovery and resource utilization of the copper slag.

[0057] In summary, the present invention provides a copper slag waste heat recovery system, which realizes the mutual combination and effective connection of the recyclable energy processing system and the production system. The granulation bin adopts a granulation method combining gas quenching and centrifugation, which has the characteristics of high operation safety and high recovery rate. Through air and water cooling in different environments, high-temperature gases and superheated steam of different temperatures are obtained, which are targeted for use in pyrolysis gasification furnaces and waste heat boilers. It not only solves the serious problem of resource waste, but also effectively realizes the efficient utilization of copper slag waste heat. After the waste heat recovery of this system, the high-temperature copper slag with an original temperature of about 1200℃~1400℃ becomes low-temperature slag particles with a temperature of about 80℃~150℃. The waste heat recovery effect is obvious and provides convenience for the subsequent flotation process.

[0058] It should be noted that when the present invention involves a numerical range, it should be understood that the two endpoints of each numerical range and any value between the two endpoints can be selected. Since the steps and methods used are the same as those in the embodiments, in order to avoid redundancy, the present invention describes a preferred embodiment. Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they know the basic creative concept. Therefore, the attached claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0059] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A copper slag waste heat recovery system, comprising a slag bag (1), characterized in that: A granulation bin (3) is provided at the slag outlet (2) of the slag ladle (1), and a spray gun (4) is provided below the slag outlet (2) and in the granulation bin (3). A rotating cup device (5) is provided on the spray gun (4). The rotating cup device (5) is used to centrifuge, crush and granulate the copper slag. At the same time, the spray gun (4) is used to air-cool and granulate the copper slag to form first hot air through heat exchange. The outlet of the granulation bin (3) is connected to a fixed bed boiler (6), the fixed bed boiler (6) is connected to a waste heat boiler (8) and a pyrolysis gasification furnace (9), and the fixed bed boiler (6) is used to perform heat exchange on the copper slag to generate second hot air after the heat exchange; The waste heat boiler (8) is connected to a power generation device (10); the first hot air and the second hot air enter the waste heat boiler (8) to exchange heat with the waste heat boiler (8) to form first superheated steam; the first superheated steam enters the power generation device (10) to generate electricity for the power generation device (10); The low-pressure steam generated by the power generation equipment (10) after power generation is used to heat the user's heat storage device for heating. The condensed water generated by the user's heat storage device for heating enters the fixed bed boiler (6) and is used by the fixed bed boiler (6) to perform heat exchange on the copper slag to generate second superheated steam. The second superheated steam enters the power generation equipment (10) and is used by the power generation equipment (10) to generate electricity. The copper slag in the slag bag (1) is subjected to a heat exchange cycle through a granulation bin (3), a fixed bed boiler (6) and a waste heat boiler (8), thereby realizing waste heat recovery of the copper slag.

2. The copper slag waste heat recovery system according to claim 1 is characterized in that: The spray gun (4) is a gas spray gun, one end of which is connected to an air compressor (7) via a first air pipe, and a first solenoid valve (V1) is provided on the first air pipe.

3. The copper slag waste heat recovery system according to claim 1 is characterized in that: The fixed bed boiler (6) adopts two heat exchange methods, namely water cooling and air cooling. The air cooling is connected to an air compressor (7) through an air pipe, and cold air is provided by the air compressor (7) to enter the fixed bed boiler (6), and the fixed bed boiler (6) exchanges heat to form the second hot air. The water cooling is that the condensed water generated by the user's heat storage device for heating enters the fixed bed boiler (6) through a drain pipe, and the fixed bed boiler (6) exchanges heat to form the second superheated steam.

4. The copper slag waste heat recovery system according to claim 1 is characterized in that: The granulating bin (3) is provided with an exhaust hole, the exhaust hole is connected to the waste heat boiler (8) through a first hot air exhaust pipe, the waste heat boiler (8) is connected to the power generation equipment (10) through a second hot air exhaust pipe, and the first hot air exhaust pipe is provided with a second solenoid valve (V2).

5. The copper slag waste heat recovery system according to claim 4 is characterized in that: The fixed bed boiler (6) is provided with a third hot air exhaust pipe, the third hot air exhaust pipe is connected to the first hot air exhaust pipe, and the third hot air exhaust pipe is provided with a third solenoid valve (V3).

6. The copper slag waste heat recovery system according to claim 4, characterized in that: The three hot air exhaust pipes are connected to a connecting pipe, and the connecting pipe is connected to a pyrolysis gasification furnace (9). The second hot air enters the pyrolysis gasification furnace (9) and is used for the pyrolysis gasification furnace (9) to perform a pyrolysis reaction. A fourth solenoid valve (V4) is provided on the connecting pipe. The pyrolysis gasification furnace (9) is provided with a first exhaust pipe, and the first exhaust pipe is connected to the three hot air exhaust pipes.

7. The copper slag waste heat recovery system according to claim 1, characterized in that: The fixed bed boiler (6) is provided with a superheated steam discharge pipe, the superheated steam discharge pipe is connected to the power generation equipment (10), and a fifth solenoid valve (V5) is provided on the superheated steam discharge pipe.

8. The copper slag waste heat recovery system according to claim 1, characterized in that: The discharge outlet of the fixed bed boiler (6) is connected to a flotation recovery device (11).

9. A method for recovering waste heat from copper slag using the copper slag waste heat recovery system according to any one of claims 1 to 8, characterized in that: The following steps are involved: The copper slag in the slag bag (1) is discharged from the slag outlet (2) into the granulation bin (3). At this time, the temperature of the copper slag is 1200° C. to 1400° C. The copper slag enters the rotating cup device (5). The rotating cup device (5) centrifuges, crushes and granulates the copper slag. At the same time, the cold air of the spray gun (4) further crushes, granulates and exchanges heat with the copper slag. The copper slag then falls into the bottom of the granulation bin (3), is cooled to 1000° C. to 1100° C. and enters the fixed bed boiler (6). The cold air from the spray gun (4) cools the copper slag to exchange heat, forming first hot air that enters the waste heat boiler (8); After the fixed bed boiler (6) performs heat exchange on the copper slag, the second hot air with a temperature of 600° C. to 800° C. is generated after the heat exchange and enters the waste heat boiler (8) and the pyrolysis gasification furnace (9). At the same time, condensed water generated by the user's heat storage device for heating enters the fixed bed boiler (6) to perform heat exchange on the copper slag to generate second superheated steam, and the second superheated steam enters the power generation equipment (10); The combustible gas generated by the pyrolysis gasification furnace (9) and the second hot air generated by the fixed bed boiler (6) after heat exchange with the copper slag heat the water in the waste heat boiler (8) to form a first superheated steam which enters the power generation equipment (10). The power generation equipment (10) generates electricity through the first superheated steam and the second superheated steam and provides electric energy to the user. The low-pressure steam generated by the power generation equipment (10) after power generation is used to heat the user's heat storage device for heating. The condensed water generated by the heating enters the fixed bed boiler (6) for heat exchange to generate a second superheated steam, thereby forming a heat exchange cycle. The fixed bed boiler (6) cools the copper slag to 80°C to 150°C through heat exchange and then discharges it for flotation process, thereby realizing waste heat recovery and resource utilization of the copper slag.

Images