阅读说明：本技术 一种含铜固废的分离方法 (Separation method of copper-containing solid waste ) 是由 王云 陈学刚 王书晓 郭亚光 裴忠冶 李冲 祁永峰 于 2020-05-26 设计创作，主要内容包括：本发明公开了一种含铜固废的分离方法,包括如下步骤,a、含铜固废制粒和烘干预处理,得到含铜固废颗粒；b、将所述含铜固废颗粒投入氧化侧吹炉熔池中,氧化侧吹炉熔池温度为1200-1300℃,含铜固废颗粒熔化,形成上层的石膏熔体和下层的含铜熔融炉渣。本发明的方法能够处理高钙、高硫、低硅、低铁特性的含铜固废,对原料预处理要求低,避免了深度烘干预处理的高温、高能耗、大烟尘量、有机物挥发量大等问题,具有显著的节能降耗效果,并且对含铜固废具有较大处理能力。(The invention discloses a separation method of copper-containing solid waste, which comprises the following steps of a, granulating the copper-containing solid waste and drying and pretreating to obtain copper-containing solid waste particles; b. and putting the copper-containing solid waste particles into an oxidation side-blown converter molten pool, wherein the temperature of the oxidation side-blown converter molten pool is 1200-1300 ℃, and the copper-containing solid waste particles are melted to form an upper-layer gypsum melt and a lower-layer copper-containing molten slag. The method can treat the copper-containing solid waste with the characteristics of high calcium, high sulfur, low silicon and low iron, has low requirement on raw material pretreatment, avoids the problems of high temperature, high energy consumption, large smoke amount, large organic matter volatilization amount and the like of deep drying pretreatment, has obvious energy-saving and consumption-reducing effects, and has large treatment capacity on the copper-containing solid waste.)

1. The method for separating the copper-containing solid waste is characterized by comprising the following steps of:

a. granulating and drying the copper-containing solid waste to obtain copper-containing solid waste particles;

b. and putting the copper-containing solid waste particles into an oxidation side-blown converter molten pool, wherein the temperature of the oxidation side-blown converter molten pool is 1200-1300 ℃, and the copper-containing solid waste particles are melted to form an upper-layer gypsum melt and a lower-layer copper-containing molten slag.

2. The method for separating copper-containing solid waste according to claim 1, wherein the moisture content of the copper-containing solid waste particles after the drying pretreatment in the step a is less than 30%.

3. The method for separating copper-containing solid waste according to claim 2, wherein the moisture content of the copper-containing solid waste particles after the drying pretreatment in the step a is 10-30%.

4. The method for separating the copper-containing solid waste according to claim 1, wherein in the step b, the oxidizing side-blown converter molten pool is sequentially provided with a feeding area, an intermediate transition area and a discharging area, spray guns are arranged below and at the bottom of the side wall of the feeding area, spray guns are arranged at the bottom of the intermediate transition area, the discharging area is a standing settling area, and gypsum melt and copper-containing molten slag are settled and separated in the discharging area.

5. The method for separating copper-containing solid waste according to claim 4, wherein the lance is protected by a water-cooled structure.

6. The method for separating the copper-containing solid waste according to claim 1 or 4, wherein in the step b, coal dust or natural gas and oxygen with the volume concentration of 85-100% are injected into the oxidation side-blown converter molten pool.

7. The method for separating the copper-containing solid waste according to claim 1, wherein in the step b, an oxidizing atmosphere is formed above the oxidizing side-blown converter molten pool.

8. The method for separating copper-containing solid waste according to claim 7, wherein in the step b, O in flue gas of the oxidation side-blown converter₂The volume concentration is 5-10%.

9. The method for separating copper-containing solid waste according to claim 1, wherein the gypsum layer obtained in the step b is sent to a rotary kiln for reduction roasting decomposition to obtain lime and SO₂Flue gas.

10. The method for separating the copper-containing solid waste according to claim 1, wherein the copper-containing molten slag obtained in the step b is sent to an electric furnace or a side-blown furnace, and is subjected to reduction smelting to obtain black copper and tailings.

Technical Field

The invention belongs to the technical field of solid waste treatment, and particularly relates to a separation method of copper-containing solid waste.

Background

The electroplating industry uses a large amount of sulfuric acid, lime is used for neutralization and sedimentation during sewage treatment, and the obtained sediment contains a large amount of copper oxide and also contains a large amount of calcium sulfate. After the sludge is primarily dried, mainly CuO and CaSO are used₄Mainly, the copper-containing solid waste is generally mixed with other copper-containing solid waste, a flux and the like to be made into blocks or pellets, reduction smelting is carried out in a side-blown furnace or a blast furnace, a part of matte is remained when black copper is generated, the melt is easy to be layered, the separation is not thorough, sulfide is easy to be mixed with tailings, the generated black copper and matte need to be separated again, the black copper is sent to electrolysis, the matte is sent to a converting furnace, the copper content of slag is about 0.8 percent, and the slag is generally used as a building material raw material or is discarded. Therefore, the prior art can only mix a small amount of the copper-containing solid wastes with high calcium and high sulfur on the premise of not influencing the product index, and the prior art has very limited capability of treating the copper-containing solid wastes.

Application No. 201611178461.3 proposes a process for the treatment of copper-containing sludge. The method comprises the steps of drying copper-containing sludge with the sulfur content of less than 2% at low temperature, making bricks, adding the dried sludge, a slagging agent and reduced coking coal into an oxygen-enriched side blowing furnace to produce secondary crude copper, carrying out ore dressing on tailings containing 0.6% of copper and then recovering residual copper, and drying the copper-containing sludge with the sulfur content of more than 2% at low temperature, and then feeding the sludge into an ore copper smelting system for synergistic treatment, wherein the process is the same as that of the conventional copper smelting process. The process can only be used for independently treating the copper-containing sludge with low sulfur content, the S content in most of the copper-containing sludge is higher than 2%, the introduction of organic matters, halogens and other substances in the copper-containing sludge can bring negative effects to a mineral copper smelting system, the copper-containing sludge is difficult to be mixed in a large proportion, the raw material adaptability of the process is poor, and the treatment capacity is limited.

Therefore, it is urgently needed to develop a separation method capable of treating copper-containing solid waste with a sulfur content of more than 2% so as to improve the treatment capacity of the copper-containing solid waste.

Disclosure of Invention

The present application is based on the discovery and recognition by the inventors of the following facts and problems:

the existing copper-containing solid waste fire treatment process generally adopts a blast furnace and a side-blown furnace for reduction smelting.

When the copper-containing solid waste is treated by the blast furnace process, the copper-containing solid waste is mixed with other low-sulfur raw materials to be made into bricks, and the bricks are aired and dehydrated, and then the bricks enter a blast furnace to be reduced and smelted, black copper and matte are generally produced, the black copper needs to be separated again to be sent to electrolysis, the matte is sent to blowing, and tailings contain about 0.8 percent of copper and need to be further subjected to ore dressing and dilution. However, the process needs longer pretreatment processes such as material mixing, briquetting, air drying and the like, a large amount of volatile organic compounds on the top of the blast furnace are difficult to treat, the obtained products need to be separated again in layers and sent to different processes for treatment, and tailings are high in copper content and difficult to utilize. In addition, the blast furnace process also has the problems of small monomer processing capacity, high labor intensity of workers, poor environment-friendly conditions of smelting workshops and the like.

When the side-blown converter process is used for treating copper-containing sludge, the copper-containing sludge needs to be dehydrated to the water content of below 10 percent in advance, the copper-containing sludge is put into a side-blown smelting furnace, heat supply and reduction are carried out in an oxygen-enriched side submerged combustion mode, in order to prevent burning loss of a spray gun, the spray gun needs to be far away from a metal and copper matte layer, the reducibility of a system is ensured in an insufficient combustion mode, meanwhile, sulfides in slag, metal and copper matte below the position of the spray gun are difficult to be oxidized and removed, tailings are easy to clamp miscellaneous copper matte particles, and the tailings still need to be subjected to slow cooling and then subjected to.

CaSO in the materials mainly processed by the existing blast furnace and side blown furnace₄Low content of CaSO₄Decomposition and reduction in the reduction smelting process are largely endothermic and consume reducing agents, and also require a large amount of silica to adjust the slag basicity, thus resulting in large consumption of flux, reducing agents and energy. For high CaSO₄The copper-containing solid waste with the content can not be treated by the prior process, and only a small amount of copper-containing solid waste can be mixed under the condition of not influencing the smelting index, so that a large amount of copper-containing solid waste can not be well utilized.

The present invention is directed to solving, at least to some extent, one of the technical problems in the related art.

Therefore, an object of the embodiments of the present invention is to provide a method for separating copper-containing solid waste, which can treat copper-containing solid waste with characteristics of high calcium, high sulfur, low silicon, and low iron, has a low requirement for raw material pretreatment, avoids the problems of high temperature, high energy consumption, large smoke amount, large organic matter volatilization amount, and the like of deep drying pretreatment, has significant energy saving and consumption reduction effects, and has a large treatment capacity for copper-containing solid waste.

To this end, an aspect of an embodiment of the present invention provides a method for separating copper-containing solid waste, including the steps of,

a. granulating and drying the copper-containing solid waste to obtain copper-containing solid waste particles;

b. and putting the copper-containing solid waste particles into an oxidation side-blown converter molten pool, wherein the temperature of the oxidation side-blown converter molten pool is 1200-1300 ℃, and the copper-containing solid waste particles are melted to form an upper-layer gypsum melt and a lower-layer copper-containing molten slag.

The method for separating the copper-containing solid waste provided by the embodiment of the invention has the following beneficial effects: the method comprises the steps of putting copper-containing solid waste with high Ca and S content into a molten pool of an oxidation side-blown converter for melting, realizing separation of an upper gypsum melt and lower copper-containing molten slag, directly feeding the copper-containing solid waste into the molten pool, controlling the oxidizing atmosphere and the lower temperature (1200℃) in the molten pool, inhibiting decomposition of calcium sulfate, avoiding massive heat absorption caused by sulfate decomposition, thoroughly decomposing organic pollutants in sludge, separating excessive calcium and sulfur in the copper-containing solid waste in the form of calcium sulfate melt, separating the lower copper-containing molten slag in advance due to massive calcium sulfate, greatly reducing the flux and reduction usage amount of the copper-containing slag in the subsequent smelting process, remarkably reducing the slag amount, reducing the lower molten slag to obtain a black copper product, and comprehensively recovering valuable metals such as Cu, Ni and the like with high recovery rate.

In some embodiments of the present invention, in the step a, the moisture content of the copper-containing solid waste particles after the drying pretreatment is less than 30%, preferably 10 to 30%.

In some embodiments of the invention, in the step b, the oxidizing side-blown converter molten pool is provided with a feeding area, an intermediate transition area and a discharging area in sequence, spray guns are arranged below and at the bottom of the side wall of the feeding area, spray guns are arranged at the bottom of the intermediate transition area, the discharging area is a standing and settling area, and the gypsum melt and the copper-containing molten slag are settled and separated in the discharging area.

In some embodiments of the invention, the lance is protected with a water-cooled structure.

In some embodiments of the invention, in the step b, coal powder or natural gas and oxygen with a volume concentration of 85-100% are injected into the oxidation side-blown converter molten pool.

In some embodiments of the invention, in the step b, an oxidizing atmosphere is provided above the oxidizing side-blown converter molten pool.

In some embodiments of the invention, in the step b, O in the flue gas of the side-blown converter molten pool is oxidized₂The volume concentration is 5-10%.

In some embodiments of the invention, the gypsum layer obtained in step b is sent to a rotary kiln for reduction roasting decomposition to obtain lime and SO₂Flue gas.

In some embodiments of the invention, the copper-containing molten slag obtained in the step b is fed into an electric furnace or a side-blown furnace, and is subjected to reduction smelting to obtain black copper and tailings.

Drawings

FIG. 1 is a process flow diagram of a method for separating copper-containing solid waste in accordance with an embodiment of the present invention;

FIG. 2 is a schematic view of an oxidizing side-blown furnace according to an embodiment of the present invention.

Reference numerals: 10-oxidizing side-blown converter; 1-a molten pool; 2-a spray gun; 3-a feed inlet; 4-a smoke outlet; 5-gypsum discharge port; 6-slag discharge port.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings. The following described embodiments are exemplary and are intended to be illustrative of the invention and are not to be construed as limiting the invention.

The method for separating the copper-containing solid waste comprises the following steps,

a. granulating and drying the copper-containing solid waste to obtain copper-containing solid waste particles;

b. and putting the copper-containing solid waste particles into an oxidation side-blown converter molten pool, wherein the temperature of the oxidation side-blown converter molten pool is 1200-1300 ℃, and the copper-containing solid waste particles are melted to form an upper-layer gypsum melt and a lower-layer copper-containing molten slag.

According to the method for separating the copper-containing solid waste, the copper-containing solid waste with high Ca and S content is put into the melting pool of the oxidation side-blown converter to be melted, so that the separation of the upper gypsum melt and the lower copper-containing molten slag is realized, the copper-containing solid waste directly enters the melting pool with the temperature of 1200-1300 ℃, not only is a great amount of heat absorption caused by sulfate decomposition avoided, but also organic pollutants in sludge can be thoroughly decomposed, excessive calcium and sulfur in the copper-containing solid waste are separated out in the form of calcium sulfate melt, the lower copper-containing molten slag is separated out in advance due to the fact that a great amount of calcium sulfate is separated out, the flux and the reduction usage amount of the copper-containing slag in the subsequent melting process are greatly reduced, the slag amount is remarkably reduced, the lower copper-containing molten slag can be reduced to obtain black copper products, and valuable metals such as.

According to some embodiments of the present invention, in the step a, the moisture content of the copper-containing solid waste particles after the drying pretreatment is less than 30%, preferably 10-30%. According to the method provided by the embodiment of the invention, the copper-containing solid waste does not need to be dried to be below 10%, and the copper-containing solid waste only needs to be dried to contain below 30% of water, so that the requirement on raw material drying is low, and the problems of high temperature, high energy consumption, large smoke amount, large organic matter volatilization amount and the like in deep drying pretreatment are avoided.

According to some embodiments of the invention, in the step b, the oxidizing side-blown converter molten pool is provided with a feeding area, an intermediate transition area and a discharging area in sequence, spray guns are arranged below and at the bottom of the side wall of the feeding area, spray guns are arranged at the bottom of the intermediate transition area, the discharging area is a standing and settling area, and the gypsum melt and the copper-containing molten slag are settled and separated in the discharging area. In the method of the embodiment of the invention, the materials are fedSide-blowing and bottom-blowing spray guns are used in the area, the number of the spray guns is large, and the heat supply intensity and the molten pool stirring intensity are high; the middle transition zone mainly supplies heat by injecting fuel through a bottom-blowing spray gun, the temperature of a molten pool is maintained, and the stirring of the molten pool gradually tends to be mild; the discharging area is a standing and settling area, a spray gun is not arranged, and no spray gun blows, and mainly promotes the settling separation of the two phases of the copper-containing molten slag and the gypsum melt. In the middle transition area and the area near the discharging area of the oxidation side-blown converter, the upper layer of gypsum melt and the lower layer of molten slag containing copper are layered, and the slag is Cu₂O-CaO-SiO₂-Fe₂O₃-Al₂O₃the-MgO multicomponent slag system is mainly, and the gypsum is CaSO₄Mainly comprises the following steps.

According to some embodiments of the invention, the lance is protected with a water-cooled structure. In the method of the embodiment of the invention, the contact position of the spray gun is the slag, the spray gun can be protected by using the water-cooling structure, and the water-cooling slag adhering can also reduce the heat loss, thereby being beneficial to prolonging the service life of the spray gun.

According to some embodiments of the invention, in the step b, coal powder or natural gas and oxygen with a volume concentration of 85-100% are injected into the oxidizing side-blown converter molten pool. In the method of the embodiment of the invention, high-concentration oxygen is injected, which is beneficial to reducing the using amount of coal dust injected in the oxidation side-blown furnace, improving the content of valuable metals such as Cu, Ni and the like in the copper-containing molten slag and recovering the valuable metals such as Cu, Ni and the like.

According to some embodiments of the invention, in the step b, an oxidizing atmosphere is arranged above the oxidizing side-blown converter molten pool, and O in flue gas₂The volume concentration is 5-10%. In the method provided by the embodiment of the invention, the excess oxygen is controlled in the process of spraying by the spray gun, so that the oxidizing atmosphere is arranged above the molten pool and mainly comprises CO₂、O₂And N₂Mainly O in the flue gas₂The concentration is controlled to be 5-10%, so that the copper-containing solid waste is heated and melted under the oxidizing condition to form a molten gypsum layer and a copper-containing molten slag layer, and the content of valuable metals such as Cu, Ni and the like in the copper-containing molten slag layer is favorably increased.

In some embodiments of the invention, the gypsum of the upper layer obtained in the step b is fed into a rotary kilnReducing, roasting and decomposing to obtain lime and SO₂Flue gas. The gypsum separated in the embodiment of the invention can be reduced and decomposed in the rotary kiln, the energy consumption is reduced when the gypsum is fed into the furnace in a hot state, the produced lime can be recycled, the flue gas can be used for preparing sulfuric acid, and the recycling of calcium and sulfur elements is realized.

Cooling the separated molten gypsum to 900 ℃ of 800-₂And Fe₂O₃Combined with CaO to form calcium silicate (CaO. SiO)₂) And calcium ferrite (CaO. Fe)₂O₃) Promoting the decomposition of gypsum to generate SO₂. The reaction is as follows:

2CaSO₄+2SiO₂＝2CaO·SiO₂+2SO₂+O₂

2CaSO₄+Fe₂O₃＝CaO·Fe₂O₃+2SO₂+O₂

at this time, the electrode supplies heat or the fuel burns, so that the atmosphere in the furnace can be controlled to be a weakly oxidizing atmosphere, and the decomposition of the calcium sulfate can be further promoted. The reaction is as follows:

CaSO₄+SiO₂+CO＝CaO·SiO₂+SO₂+CO₂

2CaSO₄+Fe₂O₃+CO＝CaO·Fe₂O₃+2SO₂+CO₂

CaO-SiO is finally formed in the electric furnace or the side-blown furnace₂-FeO_xThe slag system with low melting point can be used as building material after the tailings are water-quenched.

According to some embodiments of the invention, the copper-containing molten slag obtained in step b is fed into an electric furnace or a side-blown furnace, and is subjected to reduction smelting to obtain black copper and tailings. In the method of the embodiment of the invention, when the obtained molten slag is sent into an electric furnace or a side-blown furnace for reduction smelting, the reduction smelting temperature is 1300-1400 ℃, a black copper product and water-quenched slag can be reduced by adding a reducing agent and a fusing agent, the flue gas is reducibility, the waste heat is recovered by a waste heat boiler after secondary combustion, and the flue gas is discharged after dust removal.

Specific embodiments of the present invention will be described below with reference to fig. 1 and 2.

The copper-containing solid waste used in the following examples is granulated and dried to obtain granules, and the components are shown in table 1, wherein the water content in the materials is 12.5% by mass.

TABLE 1

Cu	TFe	FeO	S	Ni	CaO	SiO2	MgO	Al2O3	C	CO2	H2O
												16.78	7.07	8.76	5.55	1.90	15.64	2.92	1.51	1.62	4.76	16.5	12.5

Wherein sulfur is present predominantly as sulfate; calcium exists mainly in the form of calcium carbonate and calcium silicate; copper exists mainly in the form of copper sulfate and copper oxide; carbon exists mainly in the form of organic carbon, free carbon and carbonate.

As shown in fig. 2, a molten pool 1 of an oxidation side-blown converter 10 adopted in the embodiment of the present invention is sequentially provided with a feeding area I, an intermediate transition area II and a discharging area III, spray guns 2 are arranged below and at the bottom of a side wall of the feeding area I, the spray gun 2 is arranged on a side wall of the intermediate transition area II, the discharging area III is a standing and settling area, a feeding port 3 is arranged above the feeding area I, a smoke outlet 4 is arranged above the discharging area III, a gypsum discharging port 5 is arranged at a middle gypsum layer of a side wall of the discharging area III, and a slag discharging port 6 is arranged below a side wall of the discharging area III. The spray gun 2 in the oxidation side-blown converter 10 adopts a water cooling structure.