Waste heat gradient recovery system and non-ferrous metal smelting system

Abstract

The utility model relates to a waste heat gradient recovery system and a non-ferrous metal smelting system. The waste heat gradient recovery system comprises a heat exchanger, a deaerator, a coal economizer, a fire smelting waste heat boiler, a superheater and a high-pressure pump, and the heat absorption side of the heat exchanger, the deaerator, the coal economizer, a heat absorption side pipeline of the fire smelting waste heat boiler and the superheater are sequentially communicated. The high-pressure pump is arranged between the deaerator and the economizer, so that the demineralized water sequentially exchanges heat and recovers waste heat of the low-temperature area of the sulfuric acid dry absorption section, the low-temperature area of the sulfuric acid conversion section, the pyrometallurgy section and the intermediate-temperature area of the sulfuric acid conversion section. According to the waste heat gradient recovery system, low-grade waste heat in a non-ferrous metal smelting system is recovered, the waste heat recovery efficiency is improved, the steam yield is also improved, superheated steam with high-grade heat energy is finally produced by recovering different grades of waste heat, subsequent steam utilization is facilitated, and the utilization rate of the superheated steam is improved. And the energy consumption in the waste heat gradient recovery system is also reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to a waste heat recovery technical field, concretely relates to a waste heat gradient recovery system and nonferrous metal smelting system. BACKGROUND

[0002] The pyrometallurgical furnace of the pyrometallurgical section of nonferrous metal (copper, lead, tin, nickel) smelting discharges a large amount of high-temperature (800 DEG C-1300 DEG C) flue gas, in order to meet the subsequent flue gas treatment process, it must be cooled to about 350 DEG C or so. The sulfuric acid temperature of the dry absorption section of the flue gas acid making is reduced from about 207 DEG C to about 125 DEG C. In the related technology, a low-temperature heat recovery system (about 0.8 MPa) is arranged, first, the normal temperature desalted water is heated to 104 DEG C by the deaerator, then a part of desalted water is sent to each waste heat boiler of the dry absorption section of the flue gas acid making to produce low-pressure saturated steam, and another part of desalted water is sent to the fire smelting waste heat boiler of the pyrometallurgical section to produce medium-pressure saturated steam. However, the desalted water is heated to 104 DEG C, which increases energy consumption, and the desalted water at 104 DEG C directly enters the boiler heat exchange, so that some low-temperature waste heat cannot be recovered better, and the boiler feed water is raised from 104 DEG C to the saturation temperature under the pressure of the boiler, which needs to consume the heat of the boiler, and indirectly reduces the evaporation capacity of the boiler. UTILIZABLE INNOVATION

[0003] The utility model aims at solving one of the technical problems in the related technology at least to some extent.

[0004] Therefore, the embodiment of the utility model provides a waste heat gradient recovery system, which recovers the low-grade waste heat in the nonferrous metal smelting system, improves the waste heat recovery efficiency, also improves the steam production capacity, recovers the waste heat of different grades and finally produces the superheated steam of high-grade heat energy, which is not only beneficial to the subsequent steam utilization, but also reduces the energy consumption inside the waste heat gradient recovery system.

[0005] The embodiment of the utility model provides a nonferrous metal smelting system.

[0006] The waste heat gradient recovery system according to the embodiment of the utility model, including heat exchanger, deaerator, coal economizer, fire smelting waste heat boiler, superheater and high pressure pump, the heat absorption side of heat exchanger is used to communicate desalted water source, the heat release side of heat exchanger is used to be located in the low temperature area of sulphuric acid dry absorption section of nonferrous metal smelting system, coal economizer is used to be located in the low temperature area of sulphuric acid conversion section of nonferrous metal smelting system, fire smelting waste heat boiler is used to be located in the fire smelting section of nonferrous metal smelting system, fire smelting waste heat boiler has heat absorption side pipeline, superheater is used to be located in the medium temperature area of sulphuric acid conversion section of nonferrous metal smelting system, the heat absorption side of heat exchanger, deaerator, coal economizer, the heat absorption side pipeline of fire smelting waste heat boiler and superheater are sequentially communicated to recover the waste heat of low temperature area of sulphuric acid dry absorption section, low temperature area of sulphuric acid conversion section, fire smelting section and medium temperature area of sulphuric acid conversion section of nonferrous metal smelting system in proper order with the heat exchange of desalted water, high pressure pump is located between deaerator and coal economizer.

[0007] The waste heat gradient recovery system according to the embodiment of the utility model recovers the low-grade waste heat in the nonferrous metal smelting system, improves the waste heat recovery efficiency, also improves the steam production capacity, recovers the waste heat of different grades and finally produces the superheated steam of high-grade heat energy, which is beneficial to the subsequent steam utilization and reduces the energy consumption inside the waste heat gradient recovery system.

[0008] In some embodiments, the heat exchanger is a feedwater heater.

[0009] In some embodiments, the coal economizer has two and is a first coal economizer and a second coal economizer respectively, the first coal economizer and the second coal economizer are connected in series, and in the flow direction of desalted water, the first coal economizer is located upstream of the second coal economizer.

[0010] In some embodiments, the fire smelting waste heat boiler includes a smelting furnace waste heat boiler and a converting furnace waste heat boiler, and the heat absorption side pipeline of the smelting furnace waste heat boiler and the heat absorption side pipeline of the converting furnace waste heat boiler are connected in parallel.

[0011] In some embodiments, the superheater has two and is a first superheater and a second superheater respectively, and in the flow direction of desalted water, the first superheater is located upstream of the second superheater.

[0012] In some embodiments, the first superheater is arranged at the outlet of a pre-converter in the medium temperature area of the sulphuric acid conversion section, and the second superheater is arranged at the outlet of a first-stage converter in the medium temperature area of the sulphuric acid conversion section.

[0013] In some embodiments, the heat absorption side of the heat exchanger, the deaerator, the high pressure pump, the coal economizer, the fire smelting waste heat boiler and the superheater are sequentially connected by pipelines.

[0014] The non-ferrous metal smelting system of this utility model includes a pyrometallurgical section, a sulfuric acid conversion section, a sulfuric acid dry absorption section, and the aforementioned waste heat gradient recovery system. The heat release side of the heat exchanger is located in the low-temperature zone of the sulfuric acid dry absorption section, the economizer is located in the low-temperature zone of the sulfuric acid conversion section, the pyrometallurgical waste heat boiler is located in the pyrometallurgical section, and the superheater is located in the medium-temperature zone of the sulfuric acid conversion section.

[0015] In some embodiments, the superheater has two superheaters, namely a first superheater and a second superheater, which are connected in series. In the flow direction of the demineralized water, the first superheater is located upstream of the second superheater.

[0016] In some embodiments, the first superheater is located at the outlet of the pre-converter in the intermediate temperature zone of the sulfuric acid conversion section, and the second superheater is located at the outlet of the first stage of the converter in the intermediate temperature zone of the sulfuric acid conversion section. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the waste heat gradient recovery system according to an embodiment of the present invention.

[0018] Figure label:

[0019] Waste heat gradient recovery system 100, heat exchanger 1, deaerator 2, economizer 3, blast furnace waste heat boiler 4, superheater 5, high pressure pump 6. Detailed Implementation

[0020] The embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0021] The following is a reference to the appendix. Figure 1 This document describes in detail the waste heat gradient recovery system 100 and the non-ferrous metal smelting system of this utility model embodiment.

[0022] The non-ferrous metal smelting system of this utility model includes a pyrometallurgical section, a sulfuric acid conversion section, a sulfuric acid dry absorption section, and a waste heat gradient recovery system 100.

[0023] The utility model embodiment's one kind waste heat gradient recovery system 100, including heat exchanger 1, deaerator 2, coal economizer 3, fire smelting waste heat boiler 4, superheater 5 and high pressure pump 6, the heat absorption side of heat exchanger 1 is used to communicate desalted water source, and the heat release side of heat exchanger 1 is arranged in the low temperature area of sulphuric acid dry absorption section of nonferrous metal smelting system, and coal economizer 3 is arranged in the low temperature area of sulphuric acid conversion section of nonferrous metal smelting system, and fire smelting waste heat boiler 4 is arranged in the fire smelting section of nonferrous metal smelting system, and fire smelting waste heat boiler 4 has heat absorption side pipeline, and superheater 5 is arranged in the medium temperature area of sulphuric acid conversion section of nonferrous metal smelting system, and the heat absorption side pipeline of heat exchanger 1, deaerator 2, coal economizer 3, fire smelting waste heat boiler 4 and superheater 5 are sequentially communicated by pipeline, so that desalted water sequentially exchanges heat and recovers the waste heat of the low temperature area of sulphuric acid dry absorption section, the low temperature area of sulphuric acid conversion section, fire smelting section and the medium temperature area of sulphuric acid conversion section, and the high pressure pump 6 is arranged between the deaerator 2 and the coal economizer 3.

[0024] The utility model embodiment's waste heat gradient recovery system 100, in use state, normal temperature desalted water enters the heat absorption side of heat exchanger 1, in heat exchanger 1, the normal temperature desalted water of heat absorption side carries out indirect heat exchange with the low temperature area sulphuric acid of acid dry absorption section of heat release side, and the temperature of desalted water after heat exchange rises to about 90 DEG C, and the first time temperature of desalted water is raised, and then desalted water enters deaerator 2, and deaerator 2 heats desalted water to 104 DEG C and carries out deoxidization, and the second time temperature of desalted water is raised. The 104 DEG C desalted water of deaerator 2 enters high pressure pump 6, and the desalted water after pressurization of high pressure pump enters coal economizer 3, and carries out indirect heat exchange with the flue gas of acid conversion section's low temperature area in coal economizer 3, and the temperature rises to about 170 DEG C, and the third time temperature of desalted water is raised. Then, desalted water enters the heat absorption side pipeline of fire smelting waste heat boiler 4, and the flue gas of fire smelting waste heat boiler 4 further heats desalted water to the saturation temperature under boiler pressure, and produces medium pressure saturated steam. Medium pressure saturated steam enters superheater 5, and continues indirect heat exchange with the flue gas of acid conversion section's medium temperature area in superheater 5, and the temperature rises to about 400 DEG C and forms superheated steam.

[0025] The embodiment of the utility model discloses a waste heat gradient recovery system 100, is provided with heat exchanger 1 in the low temperature area of acid making dry absorption section, utilizes the lower temperature acid of the low temperature area of acid making dry absorption section to primary heating to normal temperature oxygen -removing water, not only can recover the partial low temperature waste heat of the low temperature area of acid making dry absorption section, but also can preliminary greatly promote the temperature of desalted water, thereby make oxygen -removing device 2 can consume a small amount of low pressure steam and can heat desalted water to 104 DEG C and carry out oxygen -removing, reduce energy consumption. And, is provided with economizer 3 in the low temperature area of acid making conversion section, is favorable to the low temperature flue gas of the low temperature area of acid making conversion section to heat desalted water, greatly improve the temperature of desalted water, thereby make fire and smelt waste heat boiler 4 can consume relatively less heat and can heat desalted water to the saturation temperature under the boiler pressure, reduce the energy consumption of fire and smelt waste heat boiler 4. After heat exchanger 5 heat exchange, medium pressure saturated steam forms about 400 DEG C superheated steam, can drive steam turbine to work, thereby improve steam utilization efficiency.

[0026] Therefore, the waste heat gradient recovery system 100 of the embodiment of the utility model recovers the low-grade waste heat in the non-ferrous metal smelting system, improves the waste heat recovery efficiency, also improves the steam production, recovers different grades of waste heat and finally produces high-grade heat energy superheated steam, which is not only conducive to subsequent steam utilization, but also reduces the energy consumption inside the waste heat gradient recovery system 100.

[0027] Next, the 25 DEG C normal temperature desalted water entering the waste heat gradient recovery system 100 of the embodiment of the utility model will be taken as an example for detailed description.

[0028] Specifically, the heat absorption side of the heat exchanger 1, the oxygen remover 2, the high-pressure pump, the coal economizer 3, the fire and smelt waste heat boiler 4 and the superheater 5 are sequentially communicated through pipelines. The inlet of the heat absorption side of the heat exchanger 1 is communicated with the desalted water source, the outlet of the heat absorption side of the heat exchanger 1 is communicated with the inlet of the oxygen remover 2 through the first pipeline, the outlet of the oxygen remover 2 is communicated with the inlet of the high-pressure pump through the second pipeline, the outlet of the high-pressure pump is communicated with the inlet of the coal economizer 3 through the third pipeline, the outlet of the coal economizer 3 is communicated with the inlet of the heat absorption side pipeline of the fire and smelt waste heat boiler 4 through the fourth pipeline, the outlet of the heat absorption side pipeline of the fire and smelt waste heat boiler 4 is communicated with the inlet of the superheater 5 through the fifth pipeline, and the outlet of the superheater 5 is used for communicating with the downstream steam, for example, a steam turbine power generation system.

[0029] Further, the heat exchanger 1 is a feedwater heater. The heat releasing side of the feedwater heater is arranged in the low temperature area of the sulfuric acid dry absorption section. The feedwater heater can more efficiently recover the waste heat of the low temperature sulfuric acid, improve the energy utilization rate, save energy, and reduce production cost. After heat exchange of the feedwater heater, the temperature of the low temperature sulfuric acid is reduced from 152 DEG C to 123 DEG C, and the temperature of the desalted water is increased from 25 DEG C to 85 DEG C, completing the first temperature rise of the desalted water.

[0030] The desalted water discharged from the feed water heater enters the deaerator 2, is heated to 104℃ by 0.5 MPa low pressure saturated steam in the deaerator 2, and removes oxygen in the water, and after the second heating of the desalted water is completed, the desalted water is pressurized by the high pressure pump 6 and then sent to the economizer 3.

[0031] The high pressure pump 6 pressurizes the desalted water, so that the pressure of the pressurized desalted water is greater than the operating pressure of the boiler where the economizer 3 is located. In this embodiment, the flow rate of the high pressure pump is 100 m 3 / h, and the head is 650 m.

[0032] The economizer 3 has two and is respectively a first economizer and a second economizer, and the first economizer and the second economizer are connected in series, and in the flow direction of the desalted water, the first economizer is located upstream of the second economizer.

[0033] Specifically, the first economizer is located at the outlet of the III heat exchanger 1 of the sulfuric acid conversion section, and the second economizer is located at the outlet of the IV heat exchanger 1 of the sulfuric acid conversion section, and the first economizer and the second economizer are connected by the sixth pipeline. After heat exchange through the first economizer, the temperature of the flue gas of the boiler is reduced from 185℃ to 170℃, and the temperature of the desalted water is increased from 104℃ to 109℃. After heat exchange through the second economizer, the temperature of the flue gas of the boiler is reduced from 295℃ to 207℃, and the temperature of the desalted water is increased from 109℃ to 168℃. After the desalted water is sequentially heated by the first economizer and the second economizer, the desalted water is sent to the fire smelting waste heat boiler for heat exchange.

[0034] The fire smelting waste heat boiler 4 includes a smelting furnace waste heat boiler and a converting furnace waste heat boiler, and the heat absorption side pipeline of the smelting furnace waste heat boiler and the heat absorption side pipeline of the converting furnace waste heat boiler are connected in parallel.

[0035] Specifically, the fourth pipeline and the fifth pipeline each have two, one fourth pipeline connects the outlet of the economizer 3 and the inlet of the heat absorption side pipeline of the smelting furnace waste heat boiler, and one fifth pipeline connects the outlet of the heat absorption side pipeline of the smelting furnace waste heat boiler and the inlet of the superheater 5, and the other fourth pipeline connects the outlet of the economizer 3 and the inlet of the heat absorption side pipeline of the converting furnace waste heat boiler, and the other fifth pipeline connects the outlet of the heat absorption side pipeline of the converting furnace waste heat boiler and the inlet of the superheater 5.

[0036] After the desalted water is heat exchanged by the smelting furnace waste heat boiler, the temperature of the flue gas of the boiler is reduced from 1280℃ to 353℃, and the desalted water is heated to 271℃ to reach saturation, and then continues to be heated to generate 5.6 MPa pressure saturated steam. After the desalted water is heat exchanged by the converting furnace waste heat boiler, the temperature of the flue gas of the boiler is reduced from 1133℃ to 367℃, and the desalted water is heated to 271℃ to reach saturation, and then continues to be heated to generate 5.6 MPa pressure saturated steam. The 5.6 MPa pressure saturated steam generated by the two waste heat boilers is sent to the superheater 5.

[0037] The superheater 5 has two, and is respectively a first superheater and a second superheater, which are connected in series, and the first superheater is located upstream of the second superheater in the flow direction of the desalted water.

[0038] The first superheater is arranged at the outlet of the pre-converter of the medium-temperature zone of the sulfuric acid conversion section, and the second superheater is arranged at the outlet of the first-stage converter of the medium-temperature zone of the sulfuric acid conversion section. In the first superheater, the flue gas temperature is reduced from 572 DEG C to 425 DEG C, and the saturated steam temperature is increased from 271 DEG C to 314 DEG C. In the second superheater, the flue gas temperature is reduced from 623 DEG C to 430 DEG C, and the steam temperature is increased from 314 DEG C to 400 DEG C.

[0039] The waste heat gradient recovery system 100 according to the embodiment of the present application finally generates superheated steam with a pressure of 5.0 MPa and a temperature of 400 DEG C, and the superheated steam is used to drive a steam turbine to work. Compared with the medium-pressure saturated steam generated by the low-temperature heat recovery system in the related art, the efficiency of steam utilization is increased by about 15%.

[0040] Therefore, the waste heat gradient recovery system 100 according to the embodiment of the present application reasonably organizes the process of the waste heat recovery system according to the different waste heat grades and process requirements of the non-ferrous metal smelting and acid production section and the parameters of the heated medium, performs waste heat gradient recovery, and makes the waste heat of different production sections of the entire non-ferrous metal smelting system be recovered jointly, thereby improving the waste heat recovery efficiency and the steam production capacity of the system.

[0041] In the description of the present application, it should be understood that the orientations or positional relationships indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements indicated must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0042] In addition, the terms "first" and "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first" and "second" can explicitly or implicitly include at least one of the features.

[0043] In the utility model, unless another definite provision and limitation, the terms "mount", "link", "connect", "fix" and so on should do broad sense understanding, for example, can be fixed connection, also can be detachable connection, or be integrated;Can be mechanical connection, also can be electric connection or each other can communicate;Can be direct connection, also can indirectly connect through intermediate medium, can be two element internal communication or two element mutual action relation, unless another definite limitation.For ordinary skilled person in the art, can understand the specific meaning of above terms in the utility model according to specific circumstances.

[0044] In the utility model, unless another definite provision and limitation, first feature is "on" or "under" second feature can be that first and second features directly contact, or first and second features indirectly contact through intermediate medium.Moreover, first feature "over", "above" and "on" second feature can be that first feature is directly above or obliquely above second feature, or just indicates that the horizontal height of first feature is higher than that of second feature.First feature "under", "below" and "under" second feature can be that first feature is directly below or obliquely below second feature, or just indicates that the horizontal height of first feature is less than that of second feature.

[0045] In the utility model, the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model.In the specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example.Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.In addition, the skilled person in the art can combine and combine the different embodiments or examples described in the specification and the features of different embodiments or examples without contradiction.

[0046] Although the embodiments of the utility model have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the utility model.The ordinary skilled person in the art can change, modify, replace and modify the above embodiments within the scope of the utility model.

Claims

1. A waste heat gradient recovery system (100), characterized in that, The system includes a heat exchanger (1), a deaerator (2), an economizer (3), a pyrometallurgical waste heat boiler (4), a superheater (5), and a high-pressure pump (6). The heat exchanger (1) has its heat absorption side connected to a demineralized water source, and its heat release side is located in the low-temperature zone of the sulfuric acid dry absorption section of the non-ferrous metal smelting system. The economizer (3) is located in the low-temperature zone of the sulfuric acid conversion section of the non-ferrous metal smelting system. The pyrometallurgical waste heat boiler (4) is located in the pyrometallurgical smelting section of the non-ferrous metal smelting system. The pyrometallurgical waste heat boiler (4) has heat absorption side piping. The superheater (5) is used to be installed in the medium temperature zone of the sulfuric acid conversion section of the non-ferrous metal smelting system. The heat absorption side of the heat exchanger (1), the deaerator (2), the economizer (3), the heat absorption side pipeline of the pyrometallurgical waste heat boiler (4) and the superheater (5) are connected in sequence so that the demineralized water can be used to exchange heat and recover the waste heat of the low temperature zone of the sulfuric acid dry absorption section, the low temperature zone of the sulfuric acid conversion section, the pyrometallurgical section and the medium temperature zone of the sulfuric acid conversion section in sequence. The high pressure pump (6) is installed between the deaerator (2) and the economizer (3).

2. The waste heat gradient recovery system (100) according to claim 1, characterized in that, The heat exchanger (1) is a feedwater heater.

3. The waste heat gradient recovery system (100) according to claim 1, characterized in that, The economizer (3) has two economizers, namely a first economizer and a second economizer, which are connected in series. In the flow direction of the demineralized water, the first economizer is located upstream of the second economizer.

4. The waste heat gradient recovery system (100) according to claim 1, characterized in that, The waste heat boiler (4) of the blast furnace includes a waste heat boiler of the smelting furnace and a waste heat boiler of the blowing furnace. The heat absorption side pipeline of the waste heat boiler of the smelting furnace and the heat absorption side pipeline of the waste heat boiler of the blowing furnace are connected in parallel.

5. The waste heat gradient recovery system (100) according to claim 1, characterized in that, The superheater (5) has two superheaters, namely a first superheater and a second superheater, and in the flow direction of the demineralized water, the first superheater is located upstream of the second superheater.

6. The waste heat gradient recovery system (100) according to claim 5, characterized in that, The first superheater is used at the outlet of the pre-converter located in the medium-temperature zone of the sulfuric acid conversion section, and the second superheater is used at the outlet of the first stage of the converter located in the medium-temperature zone of the sulfuric acid conversion section.

7. The waste heat gradient recovery system (100) according to claim 1, characterized in that, The heat exchanger (1) absorber side, the deaerator (2), the high-pressure pump (6), the economizer (3), the blast furnace waste heat boiler (4), and the superheater (5) are connected in sequence through pipelines.

8. A non-ferrous metal smelting system, characterized in that, The system includes a pyrometallurgical section, a sulfuric acid conversion section, a sulfuric acid dry absorption section, and a waste heat gradient recovery system (100) as described in any one of claims 1 to 7. The heat exchanger (1) is located in the low-temperature zone of the sulfuric acid dry absorption section, the economizer (3) is located in the low-temperature zone of the sulfuric acid conversion section, the pyrometallurgical waste heat boiler (4) is located in the pyrometallurgical section, and the superheater (5) is located in the medium-temperature zone of the sulfuric acid conversion section.

9. The non-ferrous metal smelting system according to claim 8, characterized in that, The superheater (5) has two superheaters, namely a first superheater and a second superheater, which are connected in series. In the flow direction of the demineralized water, the first superheater is located upstream of the second superheater.

10. The non-ferrous metal smelting system according to claim 9, characterized in that, The first superheater is located at the outlet of the pre-converter in the medium-temperature zone of the sulfuric acid conversion section, and the second superheater is located at the outlet of the first stage of the converter in the medium-temperature zone of the sulfuric acid conversion section.

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