Dry type molten slag discharging system of melting system

Abstract

The utility model provides a dry type molten slag discharging system of a melting system, which can recover waste heat, reduce energy consumption of the system and realize cyclic utilization of water resources. High-temperature slag discharged by a melting furnace is introduced into a slag extrusion groove between two rollers through a chute, and cooling water provided by a cooling water supply device is introduced into hollow inner cavities of the rollers; the two rollers roll and rotate towards the molten slag extrusion groove correspondingly based on the rolling driving structures, the two rollers extrude the molten slag while cooling the molten slag, the cooled molten slag is prevented from being hung on the wall, and irregular sheet-shaped cooled slag is generated after the molten slag is cooled.

Description

Technical Field

[0001] The utility model relates to the technical field of solid waste pyrometallurgical resource utilization, in particular to a dry slag discharging system for molten slag in a melting system. Background Art

[0002] In the current field of solid waste pyrometallurgical resource utilization, most of the equipment used for pyrometallurgical treatment of materials such as surface-treated metal-containing sludge, waste printed circuit boards, fly ash, and slag are: plasma melting furnaces, oxygen-enriched side-blowing furnaces, oxygen-enriched top-blowing furnaces, and other smelting equipment. The molten slag discharging systems of these melting equipment usually adopt water quenching slag or dry environment cooling for slag discharging. However, in actual use, it is found that the water consumption of water quenching slag in the melting equipment is large, and more than 10 tons of direct cooling water is required for high-pressure slag flushing cooling per ton of slag; not only is the water consumption large, but a high-pressure pump is needed to pressurize the slag flushing cooling water, and the power consumption of the booster pump is large. When the melting equipment uses dry environment cooling for slag discharging, usually a slag ladle is used to temporarily store the molten slag and static cooling is carried out through ambient air. This method has a long cooling time, prolongs the process cycle, and it is difficult to recycle the heat of the molten slag above 1000 degrees Celsius, wasting energy. Summary of the Invention

[0003] In order to solve the problems of high energy consumption and water consumption in the molten slag discharging system in the current field of solid waste pyrometallurgical resource utilization, the utility model provides a dry slag discharging system for molten slag in a melting system, which can recover waste heat to reduce system energy consumption and realize the recycling of water resources.

[0004] The structure of the utility model is as follows: A dry slag discharging system for molten slag in a melting system, which includes: a cooling water supply device, and is characterized in that it further includes: a slag extrusion device and a chute;

[0005] The slag extrusion device includes two rollers arranged in parallel, and between the two rollers is a slag extrusion groove. Above the slag extrusion groove is a hot slag inlet and below is a cooled slag outlet; each of the rollers is connected to a rolling drive structure;

[0006] The roller is a hollow structure, and at both ends of the roller in the length direction are respectively provided with a cooling water inlet and a cooling water outlet. The cooling water outlet and the cooling water inlet are simultaneously connected to the inner cavity of the roller. At the same time, the heights of the cooling water inlet and the cooling water outlet are both higher than the highest point of the upper surface of the roller;

[0007] The cooling water inlet is connected to the cooling water supply device, and the cooling water outlet is connected to the deaerator of the melting furnace;

[0008] The chute is inclined and arranged above the two rollers. The higher end of the chute is connected to the hot molten slag outlet of the melting furnace, and the lower end is arranged above the slag extrusion groove;

[0009] A pulley is provided below the drum.

[0010] It is further characterized in that:

[0011] The chute is a V-shaped opening groove structure;

[0012] The cooling water outlet is connected to the deaerator of the melting furnace through a water outlet pipe, and an automatic exhaust valve, a temperature sensor and a pressure sensor are arranged on the water outlet pipe;

[0013] A flow regulating valve is arranged on the water inlet pipe of the cooling water inlet;

[0014] The cooling water supply device includes: a soft water system, and the soft water system is connected to the water inlet pipe through a centrifugal pump;

[0015] The rolling drive structure includes: a frequency conversion motor and a rotating shaft. The frequency conversion motor drives the drum to rotate through the rotating shaft; the rotating shaft is a hollow shaft and is respectively arranged at both ends of the drum. One end of the rotating shaft is connected to the drum, and the inner cavity of the rotating shaft communicates with the inner cavity of the drum. The other end of the inner cavity of the rotating shaft communicates with the cooling water outlet or the cooling water inlet through a rotary joint.

[0016] A molten slag dry discharging system of a melting system provided by the present application introduces high-temperature molten slag discharged from a melting furnace into a molten slag extrusion groove between two drums through a chute, and the cooling water provided by a cooling water supply device is introduced into the hollow inner cavity of the drum; the two drums respectively perform opposite rolling rotations towards the molten slag extrusion groove based on the rolling drive structure, and while cooling the molten slag, the molten slag is extruded to prevent the cooled molten slag from hanging on the wall, and the molten slag is cooled to generate irregular flaky cooling slag; in the technical solution of the present application, during the extrusion of the molten slag discharged from the melting furnace by the drum, heat exchange occurs between the flaky structure and the cooling water inside the drum. Compared with the dry environment cooling method in the prior art, the cooling speed of the molten slag is greatly improved; in the present application, the cooling water and the molten slag do not come into direct contact, the cooling water does not change its state, and there is no loss during heat exchange. At the same time, the heated cooling water generated after heat exchange enters the deaerator of the melting furnace system for utilization. 1464 MJ of heat can be recovered per ton of slag. Compared with the direct water quenching of molten slag in the prior art, there is no water consumption and heat can be recovered, reducing the steam consumption required for the deaerator to heat and deaerate the boiler feed water. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic front view structure diagram of the molten slag dry discharging system of the melting system in the present application;

[0018] Figure 2 It is a schematic top view structure diagram of the molten slag dry discharging system of the melting system in the present application;

[0019] Figure 3 It is a schematic structural diagram of a drum;

[0020] Figure 4 It is a schematic top - view structural diagram of a chute;

[0021] Figure 5 It is Figure 1 The schematic structural diagram of the B - B cross - section of the chute in

[0022] Figure 6 It is Figure 3 The enlarged schematic diagram at position A in Specific implementation manner

[0023] As Figures 1 to 6 As shown, the present application includes a dry - discharging system for molten slag of a melting system, which includes: a cooling water supply device (not marked in the figure), a slag extrusion device, and a chute 2.

[0024] The cooling water inlet 1 - 1 is connected to the cooling water supply device. In this embodiment, the cooling water supply equipment is based on a soft - water system. The soft - water system is connected to the inlet pipeline through a centrifugal pump and sends cooling water into the cooling water inlet 1 - 1. The cooling water outlet 1 - 2 is connected to the de - aerator of the melting furnace (not marked in the figure) through an outlet pipeline.

[0025] As Figure 4 and 5 As shown, the chute 2 has a V - shaped opening structure. Based on the connecting flange 21, the trough bodies of the chute 2 are connected together, and the length of the chute 2 can be set according to the actual required length. The chute 2 is inclined and arranged above two drums 1. The higher end of the chute 2 is connected to the hot slag outlet of the melting furnace (not marked in the figure), and the lower end is arranged above the slag extrusion trough 3.

[0026] The slag extrusion device includes two drums 1 arranged in parallel. Between the two drums 1 is a slag extrusion trough 3. Above the slag extrusion trough 3 is the hot slag inlet and below is the cooled slag outlet; each drum 1 is connected to a rolling drive structure. As Figure 1 shown, the two drums 1 both roll towards the slag extrusion trough 3 in the middle of the two, and extrude the molten slag.

[0027] As Figures 1 to 3 shown, the drum 1 is a hollow structure. At both ends of the drum 1 in the length direction, a cooling water inlet 1 - 1 and a cooling water outlet 1 - 2 are respectively arranged. The cooling water outlet 1 - 2 and the cooling water inlet 1 - 1 are simultaneously connected to the inner cavity of the drum 1. At the same time, the heights of the cooling water inlet 1 - 1 and the cooling water outlet 1 - 2 are both higher than the highest point of the upper surface of the drum 1 to ensure that the drum is always filled with water, and at the same time, a small part of the high - temperature vaporized steam can be discharged from the system in time to prevent the pressure in the drum 1 from being too high and causing safety problems due to overpressure.

[0028] In this application, an indirect cooling type slag discharging machine with indirect heat exchange is constructed by two drums 1. The normal temperature soft water prepared by the soft water system is pressurized to 0.4 Mpa by a centrifugal pump and transported to the cooling water inlet 1-1 of the drum 1 in the indirect cooling type slag discharging machine. The drum 1 is of a hollow structure, with cooling water flowing inside. The heated cooling water is discharged through the rotary joint at the other end of the drum 1 to the cooling water outlet 1-2.

[0029] The molten slag at the outlet of the melting furnace falls onto the surface on one side between the rolling drums 1 through the chute 2, that is, it falls into the slag extrusion groove 3. By relative rolling, the molten slag contacts the drum 1 on the other side. The two drums 1 extrude the molten slag while cooling it to prevent the cooled molten slag from sticking to the wall. Based on the technical solution of this application, the discharged slag is irregular flakes with an equivalent diameter of 50-100 mm and a thickness of 1-10 mm, and can be crushed to corresponding sizes according to the utilization requirements of the downstream.

[0030] The drum 1 is installed on the bracket 65, and pulleys 5 are arranged at the bottom of the bracket 65. The distance between the two drums of the slag cooler can be adjusted through the rollers to adjust the thickness and size of the slag to meet the uses of the downstream slag.

[0031] A flow regulating valve 1-7 is arranged on the water inlet pipe of the cooling water inlet 1-1; an automatic exhaust valve 4, a temperature sensor 1-5 and a pressure sensor 1-6 are arranged on the water outlet pipe connecting the cooling water outlet 1-2. In specific applications, the flow regulating valve 1-7 on the cooling water inlet 1-1 is interlocked and adjusted through the monitoring of the outlet pressure and temperature of the cooling water outlet 1-2 by the temperature sensor 1-5 and the pressure sensor 1-6, so as to adjust the inlet cooling water volume, and prevent the vaporization of the outlet cooling water and the overpressure caused by the lack of cooling water volume from resulting in too high a temperature of the slag. At the same time, by arranging an automatic exhaust valve 4 on the water outlet pipe to discharge a small amount of vaporized gas in the system, it can play a role in protecting the equipment from steam blockage and high-temperature damage.

[0032] The rolling drive structure includes: a variable frequency motor 6 and a rotating shaft 1-4. The variable frequency motor 6 drives the drum 1 to rotate through the rotating shaft 1-4; the rotating shaft 1-4 is a hollow shaft and is respectively arranged at both ends of the drum 1; one end of the rotating shaft 1-4 is connected to the drum 1, and the inner cavity of the rotating shaft 1-4 is communicated with the inner cavity of the drum 1. The other end of the rotating shaft 1-4 is connected to the cooling water outlet 1-2 or the cooling water inlet 1-1 through a rotary joint 1-3. The inside of the rotary joint 1-3 is a cavity, and at the same time, it is communicated with the cooling water outlet 1-2 or the cooling water inlet 1-1 and the inner cavity of the rotating shaft 1-4. The rotary joint 1-3 is realized based on the existing technology to ensure that the cooling water outlet 1-2 or the cooling water inlet 1-1 can be kept stationary while the rotating shaft 1-4 rotates.

[0033] As Figure 6The figure shows the connection structure diagram of the rotary joint 1-3 and the rotating shaft 1-4 connected to the cold water outlet 1-2 on the right side. The inner cavity of the rotary joint 1-3 connects the rotating shaft 1-4 and the cooling water outlet 1-2, ensuring that the hot water after heat exchange can be discharged from the cooling water outlet 1-2 while the drum 1 rotates.

[0034] like Figure 3 As shown, a driving wheel 63 is arranged at the output end of the variable frequency motor 6, and a driven wheel 64 is coaxially arranged on the rotating shaft 1-4, and the driving wheel 63 and the driven wheel 64 are connected by a belt 62. A rotating shaft 1-4 is arranged at each end of the drum 1, and the rotating shaft 1-4 is rotatably arranged on a bracket 65 based on a bearing seat structure 1-5; Figure 3 In the illustrated embodiment, the variable frequency motor 6 is arranged on the side where the cooling water inlet 1-1 is located, driving the rotating shaft 1-4 on the left side to rotate. The rotating shaft 1-4 on the right side rotates following the rotating shaft 1-4 on the left side.

[0035] After the variable frequency motor 6 is started, the reducer 61 drives the driving wheel 63 to rotate, and drives the driven wheel 64 to rotate; the driven wheel 64 drives the rotating shaft 1-4 to rotate, thereby realizing the rotation of the drum 1. Each drum 1 is driven by an independent variable frequency motor 6, which can adjust the cooling speed of the slag, and at the same time, the differential speed can be used to increase the spreading area of ​​the slag on the drum surface, thereby enhancing the cooling effect.

[0036] After using the technical solution of the utility model, the specific heat capacity of the slag is about 1.2 kJ / (kg•℃), the temperature is about 1300℃, and the temperature is about 80℃ after indirect cooling with cooling water. The cooling amount required for cooling one ton of slag is 1464 MJ, the cooling water inlet temperature is about 20℃, the outlet temperature is about 95℃, and the specific heat capacity of water is 4.2 kJ / (kg•℃). The cooling water required for cooling one ton of slag is about 4.65 tons, which is more than 2 times less than the water consumption of 8-12 tons of water per ton of slag for direct water quenching. At the same time, the heat recovery rate of the slag reaches 93.8%. The comprehensive heat exchange coefficient of the roller slag cooler based on indirect water cooling in this application is about 180MJ / (m2•h), the cooling area required is about 8.0 m2 / (ton of slag•h), the rated speed of the slag cooler is 1 r / min, and the diameter is 500mm. The 95℃ hot cooling water at the drum outlet enters the deaerator of the melting furnace system for utilization. 1464 MJ of heat can be recovered per ton of slag. Compared with direct water quenching of slag, there is no water consumption and heat can be recovered, which reduces the steam consumption required for thermal deoxidation in the deaerator and realizes rapid cooling of the slag.

Claims

1. A slag dry discharging system for a melting system, comprising: The cooling water supply device is characterized in that it also includes: a slag extrusion device and a chute; The slag extrusion device comprises two rollers arranged in parallel, a slag extrusion groove is provided between the two rollers, a hot slag inlet is provided above the slag extrusion groove and a cooling slag outlet is provided below the slag extrusion groove; each of the rollers is connected to a rolling drive structure; The drum is a hollow structure, and a cooling water inlet and a cooling water outlet are respectively arranged at both ends of the drum in the length direction, and the cooling water outlet and the cooling water inlet are connected to the inner cavity of the drum at the same time, and the heights of the cooling water inlet and the cooling water outlet are both higher than the highest point of the upper surface of the drum; The cooling water inlet is connected to the cooling water supply device, and the cooling water outlet is connected to the deaerator of the melting furnace; The chute is obliquely arranged above the two rollers, the higher end of the chute is connected to the hot slag outlet of the melting furnace, and the lower end is arranged above the slag extrusion trough; A pulley is arranged below the drum.

2. The slag dry discharging system of a melting system according to claim 1, characterized in that: The chute is a V-shaped open chute structure.

3. The slag dry discharging system of a melting system according to claim 1, characterized in that: The cooling water outlet is connected to the deaerator of the melting furnace through a water outlet pipeline, and an automatic exhaust valve, a temperature sensor and a pressure sensor are arranged on the water outlet pipeline.

4. The slag dry discharging system of a melting system according to claim 1, characterized in that: A flow regulating valve is arranged on the water inlet pipe of the cooling water inlet.

5. The slag dry discharging system of a melting system according to claim 4, characterized in that: The cooling water supply equipment comprises: a soft water system, and the soft water system is connected to the water inlet pipe through a centrifugal pump.

6. The slag dry discharging system of a melting system according to claim 1, characterized in that: The rolling drive structure includes: a variable frequency motor and a rotating shaft, the variable frequency motor drives the roller to rotate through the rotating shaft; the rotating shaft is a hollow shaft, which is respectively arranged at both ends of the roller, one end of the rotating shaft is connected to the roller, and the inner cavity of the rotating shaft is connected to the inner cavity of the roller, and the other end of the inner cavity of the rotating shaft is connected to the cooling water outlet or the cooling water inlet through a rotating joint.

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