WO2017157278A1

WO2017157278A1 - Metal smelting furnace

Info

Publication number: WO2017157278A1
Application number: PCT/CN2017/076589
Authority: WO
Inventors: 邓长友
Original assignee: 广州众煌电子科技有限公司
Priority date: 2016-03-18
Filing date: 2017-03-14
Publication date: 2017-09-21
Also published as: CN105627745A; CN105627745B

Abstract

A metal smelting furnace includes a furnace bottom (10), a furnace wall (7), a furnace top wall (2), a furnace door (1) and a furnace hearth; wherein the upper half portion of the furnace hearth is a hot smoke gas chamber (4), and the lower half portion of the furnace hearth is used to dispose metals to be heated; a reinforcing heat transfer layer (8) for improving heat absorption rate of the metal is provided between the upper half portion and the lower half portion of the furnace hearth. The metal smelting furnace improves heat transfer intensity of heat of the hot smoke gas in the upper half portion of the furnace hearth transferred to the metal to be heated in the lower half portion of the hearth to more than twice to tens of times, which directly results in a reduced temperature of exhaust smoke and a reduced heat loss, meanwhile increasing the temperature rise rate of the metal and shortening the fuel burning time.

Description

Metal smelting furnace

Technical field

The invention belongs to the technical field of metallurgy and relates to an efficient and energy-saving metal smelting furnace.

Background technique

The metal smelting industry is a high-energy and high-pollution industry. As energy prices continue to rise, fuel consumption costs account for a higher proportion of processing costs, accompanied by large consumption of natural resources, large amounts of carbon emissions, and severe environmental pollution. . In order to reduce the fuel consumption in the production process of metallurgical furnaces, relevant research institutions and production companies are constantly exploring new technologies to reduce costs while reducing environmental pollution.

At present, the new inventions and new technologies in the metallurgical industry's metal smelting furnace energy conservation and efficient use of fuel are mainly concentrated in two aspects: one is to achieve full combustion of fuel through new technology; the other is to recover waste heat as much as possible.

However, in the above-mentioned fuel full combustion and recovery of waste heat, the current technology has been very mature, and has reached the limit, it is difficult to conduct research in such aspects to improve the energy-saving performance of the smelting furnace.

Therefore, it is necessary to carry out development research to provide a new technical solution that is different from fuel full combustion technology or waste heat recovery technology, so as to improve heat energy utilization and achieve more energy saving purposes.

Summary of the invention

In order to solve the above problems, an object of the present invention is to provide a metal smelting furnace to improve the utilization rate of heat energy to achieve more energy saving purposes.

To achieve the above object, the technical solution of the present invention is:

A metal smelting furnace comprises a furnace bottom, a furnace wall, a furnace top wall, a furnace door and a furnace; wherein the upper part of the furnace is a hot smoke chamber, and the lower part is placed with a metal to be heated; Half part and An enhanced heat transfer layer for increasing the heat absorption rate of the metal is provided between the lower portions.

Further, a combustion system is also included, and the combustion system claimed includes a tuyere and a fire mouth.

Further, the thermally conductive material powder is sprayed into the hot flue gas chamber, and the powder gradually accumulates to form an enhanced heat transfer layer.

Further, the reinforcing heat transfer layer is outwardly arranged to be closely connected to the inner small holes.

Further, the powder is sprayed into the hot flue gas chamber by the tuyere of the combustion system, the fire mouth, the hot flue gas chamber or another pipe.

Further, the reinforced heat transfer layer is in close contact with the metal surface.

Further, the heat transfer enhancement ratio of the heat transfer enhancement layer is greater than 0.3.

Further, the enhanced heat transfer layer has a thickness of 0.5 cm to 20 cm.

Another technical solution of the present invention is a method for manufacturing a metal smelting furnace, comprising the following steps:

Providing a metal smelting furnace body, wherein the metal smelting furnace body comprises: a furnace bottom, a furnace wall, a furnace top wall, a furnace, a furnace door, and a combustion system; the upper part of the furnace is a hot smoke chamber, and the lower half Partially placed smelted metal;

An enhanced heat transfer layer for increasing the heat absorption rate of the metal is provided between the upper half and the lower half of the furnace.

Further, a silicon carbide-based powder is sprayed into the hot flue gas chamber, and the powder gradually accumulates to form an enhanced heat transfer layer.

Compared with the prior art, the metal smelting furnace of the present invention transfers the heat of the hot flue gas in the upper half of the furnace to the heat transfer intensity of the heated metal in the lower half to more than double to several tens of times, directly causing the row The reduction of the temperature of the smoke reduces the heat loss, and the speed of the metal heating increases the fuel burning time, which can produce significant energy saving effects.

DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly described below. It is obvious that the drawings in the following description are only some embodiments of the present invention. For those skilled in the art, it is also possible to The figure obtains other figures.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic view showing the principle of a metal smelting furnace of the present invention

Fig. 2 is a view showing a metal smelting furnace when no heat transfer enhancement layer is provided.

Figure 3 is a cross-sectional view taken along line A-A of Figure 1.

detailed description

Embodiments of the present invention provide an energy-efficient metal smelting furnace that enhances heat absorption in a metallurgical process to increase metal heat absorption.

In terms of heat transfer, the endothermic heat of the metal in the metal smelting furnace is completed by the convective heat transfer of the metal surface (ie, the interface between the upper and lower portions of the furnace) and the heat transfer of the metal surface absorbing radiation. In the non-ferrous metallurgy smelting process, since the blackness of non-ferrous metals is generally low (such as the blackness of aluminum and aluminum alloys is less than 0.25), the absorption ratio of heat radiation is also low, and the surface of the heated metal is radiated and heat-transferred. The efficiency of receiving heat is very low (for example, aluminum and aluminum alloys only receive less than 30% of the heat from the top of the furnace and the furnace wall); in addition, the convective heat transfer mode is limited by the limited area of the metal surface and hot smoke. The limited flow velocity of the gas, so the current convection heat transfer intensity of the metal smelting furnace is also very limited.

The invention greatly improves the efficiency and speed of convection and radiation heat transfer through a new heat transfer technology scheme, and can have a significant impact on the energy saving and consumption reduction of the entire metal smelting furnace.

In order to make the object, the features and the advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. The described embodiments are only a part of the embodiments of the invention, and not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention are within the scope of the present invention.

The terms "first", "second" and the like in the specification and claims of the present invention and the above drawings are used to distinguish similar objects, and are not necessarily used to describe a particular order or order. It is to be understood that the terms so used are interchangeable as appropriate, and are merely illustrative of the manner in which the objects of the same. In addition, the terms "including" and "having" and Any variations thereof are intended to cover non-exclusive inclusions, so that a process, method, system, product, or device that comprises a series of units is not necessarily limited to those elements, but may include those not explicitly listed or Other units inherent to the product or equipment.

The details are described below separately.

The metal smelting furnace of the present invention forms an enhanced heat transfer layer by inputting a powder of a heat conductive material to a hot flue gas in a metal smelting furnace and a heated metal (solid or liquid).

As an embodiment of the present invention, the heat transfer layer is closely spaced from the outer surface to the inner portion, and the heat transfer layer is not required to have the same thickness or the same density. When the hot flue gas passes through these small holes, the convective heat transfer area is increased by several times to several hundred times than the original convective heat transfer area (ie, the surface area of the metal and the area of the upper and lower part of the furnace is approximately equal to the area of the furnace), due to the convective heat transfer amount. It is proportional to the convection area and thus enhances the convective heat transfer rate. Secondly, the small holes also increase the convection heat transfer coefficient and the absorption ratio of the heat transfer layer.

As another embodiment of the present invention, the radiation absorption ratio of the heat transfer layer is 2-5 times higher than that of the heated metal (solid or liquid), and the absorption amount of the radiant heat energy is proportional to the absorption ratio of the object itself, and the heat transfer is performed. The layer increases the heat absorption rate of the refractory material of the upper half of the furnace by 2-5 times. Artificial black bodies can also be used. Experiments have shown that energy saving effects can be produced as long as the absorption ratio of the heat transfer layer is higher than the absorption ratio of the metal surface.

As another embodiment of the present invention, the heat transfer layer material is a high thermal conductivity material, and the higher the thermal conductivity is, the better the cost permits, and the absorbed heat energy can be quickly transferred to the heated metal. In the embodiment of the invention, the material of the heat transfer layer is based on silicon carbide. Of course, using a better thermal conductive material such as graphene as the base material will achieve better results. It has been proved that the thermal conductivity of the heat transfer layer material of the present invention can produce an energy-saving effect as long as it is greater than 1 w/mk. If the thermal conductivity of the material is greater than 5 w/mk, a relatively good effect can be obtained. In the embodiment of the invention, the heat transfer layer material The thermal conductivity is 2w/mk-8w/mk.

Specifically, as shown in FIG. 1, the metal smelting furnace of the present invention comprises a furnace bottom 10, a furnace wall 7, a top wall 2, a furnace, a furnace door 1, and a combustion system; wherein the upper part of the furnace is hot smoke In the gas chamber 4, the smelted metal (including the solid metal 11 or the liquid metal 12) is placed in the lower half, and the aluminum melting furnace is used in this example. For example, an enhanced heat transfer layer 8 for increasing the heat absorption rate of the metal is provided between the upper half and the lower half of the furnace, and the thickness of the heat transfer enhancement layer is 0.5 cm to 20 cm, which is in the embodiment of the present invention. It is about 2 cm; the combustion system includes a vent 5 and a crater 3. When feeding, open the furnace door 1. After the feeding is completed, close the furnace door to prevent heat loss. As an embodiment of the present invention, the combustion system is a diffusion type regenerative combustion system, and the flame enters from the fire port 3 into the upper portion of the hot flue gas chamber 4 of the furnace.

As shown in FIG. 2, the combustion system injects fuel and preheated air into the hot flue gas chamber 4 through the fire port 3 and the tuyere 5, respectively, when the hot flue gas generated by the mixed combustion of the gas and the air is in the hot flue gas at a certain speed. The chamber 4 flows, as shown in Fig. 2, and the flame enters the furnace along the arrow 1A in the fire port 3.

When the heat transfer layer is not strengthened, the hot flue gas generated by the flame directly generates convective heat transfer to the surface of the heated metal (solid metal 11 or liquid metal 12) to directly heat the metal (solid metal 11 or liquid metal 12), as shown in FIG. It is shown that the high temperature flue gas approaches the metal in the direction indicated by the arrow 2A, and the low temperature flue gas leaves the metal in the direction indicated by 4A after the heat exchange. Another portion of the high temperature flue gas generated by the flame is convectively heated along the arrow 2A with the hot flue gas chamber side wall 7 and the upper furnace top 2 to heat the side furnace wall 7 and the upper furnace top 2, the side and upper portions of the furnace wall 7 The roof 2 wall is heated to generate infrared rays 6 to radiate heat to the lower half of the metal (solid metal 11 or liquid metal 12).

After the heat transfer layer 8 is strengthened, as shown in FIG. 3, the high temperature flue gas approaches the direction of the arrow 2A and enters the enhanced heat transfer layer 8. After the heat exchange, the low temperature flue gas flows out in the direction indicated by 4A and leaves the enhanced heat transfer layer. 8. Another portion of the high temperature flue gas generated by the flame is convectively heated along the arrow 2A with the hot flue gas chamber side wall 7 and the upper furnace top 2 to heat the side furnace wall 7 and the upper furnace top 2, the side and upper portions of the furnace wall 7 After the wall of the furnace top 2 is heated, infrared rays 6 are generated to radiate heat to the enhanced heat transfer layer 8. The heat is thermally conducted through the enhanced heat transfer layer in the direction indicated by the arrow 3A to heat the metal.

In the embodiment of the present invention, a layer of about 2 cm of heat-enhancing heat transfer layer 8 is disposed between the upper half and the lower half of the furnace, and the heat-transfer layer 8 is reinforced with a small hole communicating with the inside of the heat-transfer layer 8. material (thermal conductivity greater than 1w / mk, a specific gravity 2.0-2.4 tons / m ^3). As shown in Fig. 3, the combustion system provides appropriate power to make the hot flue gas flow velocity in the hot flue gas chamber 4 consistent with the original, when the hot flue gas flows downward and the reinforced heat transfer layer 8 generates convection, and the hot flue gas is enhanced. The innumerable small holes of the hot layer 8 enter and exit, which increases the heat exchange area and greatly increases the heat absorbed by the heat transfer layer.

The reinforcing heat transfer layer 8 is externally connected to the inner dense pores to make the heat transfer layer become an artificial black body, thereby greatly increasing the absorption of the radiant energy by the heat transfer enhancement layer 8. In the embodiment of the invention, the heat transfer layer is strengthened. The absorption ratio of 8 pairs of radiant energy is α>0.6.

The enhanced heat transfer layer 8 is in intimate contact with the surface of the metal (solid metal 11 or liquid metal 12), the distance between them approaches zero, and the heat transfer rate tends to infinity.

As another embodiment of the present invention, a heat-enhancing heat transfer layer 8 made of a heat-conductive refractory material and increasing the heat absorption rate of the metal is provided between the upper half and the lower half of the furnace. The enhanced heat transfer layer 8 is formed by spraying a silicon carbide-based powder. The powder is sprayed into the hot flue gas chamber 4 from the tuyere 5 of the combustion system, the fire port 3, or the other pipe is directly injected into the hot flue gas chamber 4. At this time, the powder gradually accumulates to form the enhanced heat transfer layer 8. During the accumulation process, the inner portion of the heat transfer layer 8 is partially densely connected with the interconnected pores, and the heat transfer layer 8 is not soft and hard to adhere to the metal (solid metal 11 or liquid). The surface of the metal 12) has an absorption ratio of about 0.6 to 0.7, that is, about 2-3 times that of the aluminum metal. The reinforced heat transfer layer 8 formed in this manner has a minimum of pores 9 between the metal and the metal.

The invention forms a strengthening heat transfer layer 8 between the hot flue gas in the metallurgical furnace and the heated metal (solid 11 or liquid 12) by inputting a powder of a thermally conductive material, thereby creating a technical solution suitable for the heat transfer of the metallurgical furnace. The heat transfer of the upper half of the fuel in the furnace to the hot flue gas can be transferred to the heat transfer intensity of the heated metal in the lower half to more than two times to several tens of times, thereby improving the heat energy utilization rate, directly causing the exhaust gas temperature to decrease and reducing the heat. Loss and accelerated metal heating rate shorten the fuel burning time and produce significant energy saving effects.

Another embodiment of the present invention provides a method of manufacturing a metal smelting furnace, comprising the following steps:

Providing a metal smelting furnace body, wherein the metal smelting furnace body comprises: a furnace bottom 10, a furnace wall 7, a furnace top wall 2, a furnace, a furnace door 1, and a combustion system; the upper part of the furnace is hot flue gas In the lower part of the chamber 4, the metal to be smelted (including the solid metal 11 or the liquid metal 12, in this example, an aluminum melting furnace is taken as an example);

A layer is provided between the upper half and the lower half of the furnace for increasing the heat absorption rate of the metal. The heat transfer layer 8, the thickness of the enhanced heat transfer layer is 0.5cm-20cm, in the embodiment of the present invention is about 2cm;

A crater 3 and a crater are provided in the combustion system for injecting fuel and preheated air into the hot flue gas chamber 4.

When feeding, open the furnace door 1. After the feeding is completed, close the furnace door to prevent heat loss. As shown in Fig. 2, the flame enters into the upper portion of the hot flue gas chamber 4 in the upper portion of the furnace as indicated by arrow 1A in the crater 3.

As shown in FIG. 3, the high temperature flue gas generated by the flame enters the enhanced heat transfer layer 8 as indicated by the arrow 2A, and the heat in the hot flue gas is absorbed by the enhanced heat transfer layer 8. Another portion of the high temperature flue gas generated by the flame is convectively heated along the arrow 2A with the hot flue gas chamber side wall 7 and the upper furnace top 2 to heat the side furnace wall 7 and the upper furnace top 2, the side and upper portions of the furnace wall 7 The top wall 2 is heated to generate infrared rays 6 to radiate heat to the enhanced heat transfer layer 8. The heat-enhancing heat transfer layer 8 thermally conducts the absorbed heat energy in the direction indicated by the arrow 3A to heat the metal (solid metal 11 or liquid metal 12).

In the embodiment of the present invention, an ordinary heat conductive ceramic material (thermal conductivity greater than 1 w/mk, specific gravity 2.0-2.4 ton/m ³ ) may be used in the small hole in which the heat transfer layer 8 is externally connected to the inside. As shown in Fig. 3, the combustion system provides appropriate power to make the hot flue gas flow velocity in the hot flue gas chamber 4 consistent with the original, when the hot flue gas flows downward and the reinforced heat transfer layer 8 generates convection, and the hot flue gas is enhanced. The innumerable small holes of the hot layer 8 enter and exit, which increases the heat exchange area and greatly increases the heat absorbed by the heat transfer layer.

The reinforcing heat transfer layer 8 is externally connected to the inner dense pores to make the heat transfer layer become an artificial black body, thereby greatly increasing the absorption of the radiant energy by the heat transfer enhancement layer 8. In the embodiment of the invention, the heat transfer layer is strengthened. The absorption ratio of 8 pairs of radiant energy is α>0.6. The enhanced heat transfer layer 8 is in intimate contact with the surface of the metal (solid metal 11 or liquid metal 12), the distance between them approaches zero, and the heat transfer rate tends to infinity.

As an embodiment of the present invention, the enhanced heat transfer layer 8 is formed by injecting a silicon carbide-based powder. The powder is sprayed into the hot flue gas chamber 4 from the tuyere 5 of the combustion system, the fire port 3, or the other pipe is directly injected into the hot flue gas chamber 4. At this time, the powder gradually accumulates to form the enhanced heat transfer layer 8. During the accumulation process, the inner portion of the heat transfer layer 8 is partially densely connected with the interconnected pores, and the heat transfer layer 8 is not soft and hard to adhere to the metal (solid metal 11 or liquid). The surface of the metal 12) has an absorption ratio of about 0.6 to 0.7, that is, about 2-3 times that of the aluminum metal. The reinforced heat transfer layer 8 formed in this manner has a minimum of pores 9 between the metal and the metal.

The metal smelting furnace manufactured by the method of the invention forms an enhanced heat transfer layer 8 between the hot flue gas in the metallurgical furnace and the heated metal (solid 11 or liquid 12) by inputting the powder of the heat conductive material, thereby creating a heat for strengthening the metallurgical furnace. The technical solution passed. The heat transfer of the upper half of the fuel in the furnace to the hot flue gas can be transferred to the heat transfer intensity of the heated metal in the lower half to more than two times to several tens of times, thereby improving the heat energy utilization rate, directly causing the exhaust gas temperature to decrease and reducing the heat. Loss and accelerated metal heating rate shorten the fuel burning time and produce significant energy saving effects.

The invention can be applied to all non-ferrous metals aluminum, magnesium, potassium, sodium, calcium, barium, strontium, copper, lead, zinc, tin, cobalt, nickel, strontium, mercury, cadmium, strontium, gold, silver, platinum, rhodium, ruthenium , palladium, rhodium, iridium, ruthenium, lithium, osmium, iridium, titanium, zirconium, hafnium, vanadium, niobium, tantalum, tungsten, molybdenum, gallium, indium, lanthanum, cerium, lanthanum, cerium, lanthanum, cerium, lanthanum, cerium , 铕, 钆, 铽, 镝, 钬, 铒, 铥, 镱, 镥, 钪, 钇, silicon, boron, selenium, tellurium, arsenic, antimony. The part that enhances the convective heat transfer can also save energy for ferrous metal iron (steel), manganese, and chromium.

In conclusion, the above embodiments are only used to explain the technical solutions of the present invention, and are not limited thereto; although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still The technical solutions described in the above embodiments are modified, or equivalent to some of the technical features are included; and the modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

A metal smelting furnace comprises a furnace bottom, a furnace wall, a furnace top wall, a furnace door and a furnace, wherein the upper part of the furnace is a hot smoke chamber, and the lower part is placed with a metal to be heated; An enhanced heat transfer layer for increasing the heat absorption rate of the metal is provided between the upper half and the lower half.
A metal smelting furnace according to claim 1, further comprising a combustion system, said combustion system comprising a tuyere and a crater.
The metal smelting furnace according to claim 1, wherein the powder of the heat conductive material is sprayed into the hot flue gas chamber, and the powder gradually accumulates to form the heat transfer enhancement layer.
A metal smelting furnace according to claim 3, wherein said heat-strengthening heat-transfer layer has an outer surface and an inner small hole which communicate with each other.
The metal smelting furnace according to claim 3, wherein the powder is sprayed into the hot flue gas chamber by a tuyere or a fire port of the combustion system, or is injected into the hot flue gas chamber or another pipe.
A metal smelting furnace according to claim 4 or 5, wherein the reinforced heat transfer layer is in close contact with the metal surface (when the metal is in a solid state) or partially immersed in the metal (when the metal is in a liquid state).
A metal smelting furnace according to claim 4 or 5, wherein said heat transfer enhancement layer has a heat radiation absorption ratio α of more than 0.3.
The metal smelting furnace according to claim 4 or 5, wherein the reinforced heat transfer layer has a thickness of 0.5 cm to 20 cm.
A method for manufacturing a metal smelting furnace includes the following steps:

Providing a metal smelting furnace body, wherein the metal smelting furnace body comprises: a furnace bottom, a furnace wall, a furnace top wall, a furnace, a furnace door, and a combustion system; the upper part of the furnace is a hot smoke chamber, and the lower half Partially placed smelted metal;

An enhanced heat transfer layer for increasing the heat absorption rate of the metal is provided between the upper half and the lower half of the furnace.
A method of producing a metal smelting furnace according to claim 9, wherein a graphene-based powder is sprayed into the hot flue gas chamber, and the powder is gradually accumulated to form an enhanced heat transfer layer.
A method of producing a metal smelting furnace according to claim 9, wherein a powder based on silicon carbide is sprayed into the hot flue gas chamber, and the powder is gradually accumulated to form an enhanced heat transfer layer.