Titanium slag waste gas waste heat utilization system and method thereof

Abstract

The invention relates to a titanium slag waste gas waste heat utilization system and method in the technical field of waste heat recycling. The titanium slag waste gas waste heat utilization system mainly comprises a grate cooler unit, a boiler barrel, an evaporator, a superheater, a coal economizer and a control assembly. Wherein the grate cooler unit is used for cooling titanium slag and transmitting high-temperature flue gas formed in the cooling process into a boiler flue, the grate cooler unit is used for heating an evaporator, a superheater and a coal economizer which are arranged in the boiler flue, and the evaporator, the superheater and the coal economizer are communicated with a boiler barrel to form a heat transmission system for generating superheated steam and transmitting the superheated steam to the outside. The control assembly ensures stable operation of the titanium slag waste gas waste heat utilization system by controlling work of the grate cooler unit and the water supply amount of the boiler barrel. The DCS controller regulates peak shifting operation of the grate cooler and the water supply amount of the boiler barrel according to the heat average value of the grate cooler unit, stable output of titanium slag waste heat within the preset heat value interval value is achieved, stable operation of the waste heat boiler is guaranteed, the utilization efficiency of the waste heat is practically improved, and the energy consumption is reduced. The technical problems that due to intermittent cooling of the titanium slag, system operation is unstable, and external energy needs to be supplemented for assistance are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of waste heat recovery and utilization, specifically, the technical field classification number relates to F24F11 / 70, and more specifically, to a titanium slag waste gas waste heat utilization system and method. Background Art

[0002] In the process of smelting titanium-rich materials, the industry adopts the technology of cooling titanium slag with grate coolers. However, the process of cooling titanium slag with grate coolers is intermittent and discontinuous. The waste heat conditions (flue gas volume, flue gas temperature) emitted during the production process change periodically, and the flue gas volume of a single waste gas fluctuates between 0 and 100%, and the waste heat of the waste gas is always unstable. At present, the industry cannot efficiently utilize this type of waste heat and convert it into waste heat power generation. It can only be cooled and discharged after adding traditional processes such as water cooling or air cooling equipment. This not only causes serious waste of energy, but also causes thermal pollution to the environment. Similarly, other industries also have similar problems with waste heat recovery and treatment of waste gas characteristics.

[0003] The waste heat from the exhaust gas during the cooling process of titanium slag is not only intermittent and discontinuous, but also the flue gas volume and flue gas temperature change periodically. The entire waste heat flue gas conditions have complex working conditions. Therefore, under the existing titanium slag cooling process, how to efficiently and stably utilize this waste heat from the exhaust gas to convert it into electrical energy has become a major problem in the industry.

[0004] For example, the Chinese invention patent with publication number CN103307893A discloses a grate cooler waste heat recovery system, which involves a cement kiln head waste heat recovery device, including a grate cooler, and also a waste heat boiler and a primary economizer in parallel, wherein the waste heat boiler and the primary economizer take air from different positions of the grate cooler and exhaust air from the same waste gas fan, the waste heat boiler takes air from the front and / or middle of the grate cooler, the primary economizer takes air from the rear of the grate cooler, and the water outlet of the primary economizer is connected to the water inlet of the cold end economizer of the waste heat boiler. This patent technology has the above-mentioned corresponding problems. Summary of the invention

[0005] In view of the defects in the prior art, the object of the present invention is to provide a titanium slag waste gas waste heat utilization system and method.

[0006] According to the present invention, a titanium slag waste gas waste heat utilization system includes a grate cooling unit, a boiler drum, an evaporator, a superheater, an economizer and a control component;

[0007] The grate cooling unit is composed of a plurality of grate coolers arranged in parallel, and the plurality of grate coolers are respectively recorded as the first grate cooler, ..., the Nth grate cooler, wherein N is a natural number greater than 1, and the plurality of grate coolers arranged in parallel transfer waste heat to the flue of the waste heat boiler through a heat transfer channel, the evaporator, the superheater and the economizer are arranged in the flue of the boiler, the water outlet of the economizer is communicated with the water inlet of the drum, the water outlet of the drum is communicated with the water inlet of the evaporator, the steam outlet of the evaporator is communicated with the air inlet of the drum, the air outlet of the drum is communicated with the air inlet of the superheater, and the air outlet of the superheater is communicated with an external device;

[0008] The control component includes a DCS controller and a calorific value detection component. The calorific value detection component is provided in each grate cooler. The DCS controller determines the start time of the Nth grate cooler and the water supply amount of the boiler drum according to the collected average calorific values ​​of the first grate cooler to the N-1th grate cooler.

[0009] In some implementations, the number of the grate coolers in the grate cooler unit is 2-5.

[0010] In some embodiments, a heat storage body is provided in the heat transfer channel, and the inner layer of the heat storage body is a heat-insulating material, and the outer layer is a refractory material.

[0011] In some embodiments, the heat storage body is a strip body or a mesh body, and a plurality of the heat storage bodies are arranged in a front-to-back staggered manner in the heat transfer channel.

[0012] In some embodiments, the calorific value detection component includes a smoke flow meter and a smoke temperature detector.

[0013] In some embodiments, the boiler drum is provided with a water level gauge main pipe and a water level gauge connecting manifold. The water level gauge main pipe is connected in series with water level gauges arranged at different positions outside the boiler drum through the water level gauge connecting manifold. The water level gauge main pipe measures the water level of the boiler drum and transmits it to the DCS controller.

[0014] The present invention also provides a method for utilizing the waste heat of titanium slag waste gas, which uses the titanium slag waste heat utilization system and includes the following steps:

[0015] S1, multiple grate coolers are connected in parallel to form a grate cooling unit, the grate cooling unit is connected to the boiler flue through a heat transfer channel, an evaporator, a superheater and an economizer are arranged in the boiler flue, the economizer water outlet is connected to the drum water inlet, the drum water outlet is connected to the evaporator water inlet, the evaporator steam outlet is connected to the drum air inlet, the drum air outlet is connected to the superheater air inlet, and the superheater air outlet is connected to an external device;

[0016] S2, titanium slag is transported from the smelting furnace to each of the grate coolers in the grate cooler unit, the DCS controller first controls the first grate cooler to start operation, the flue gas flow meter and the flue gas temperature detector transmit parameters to the DCS controller in real time, and the DCS controller controls the water supply from the economizer to the boiler drum according to the calorific value collected in the first grate cooler;

[0017] S3, when the DCS controller controls the second grate cooler to start when the calorific value in the first grate cooler is lower than a predetermined value, the flue gas in the second grate cooler is mixed with the flue gas in the first grate cooler in the heat transfer channel and then introduced into the boiler flue, and at the same time, the DCS controller controls the water supply of the drum according to the average of the calorific values ​​of the first grate cooler and the second grate cooler obtained by collection and calculation;

[0018] S4, repeat the procedure of step S3 until the DCS controller starts the Nth grate cooler.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] The present invention obtains the staggered operation of the grate cooler and the water supply to the drum according to the heat mean value of the grate cooler unit through the DCS controller, so as to achieve stable output of the waste heat of the titanium slag within a predetermined calorific value range, ensure the stable operation of the waste heat boiler, effectively improve the utilization efficiency of the waste heat, and solve the technical problem of unstable system operation caused by intermittent cooling of the titanium slag and the need to supplement external energy as an auxiliary. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0022] Figure 1 This is a schematic diagram of the overall structure of the titanium slag cooling waste gas waste heat utilization system of the present application;

[0023] Figure 2 yes Figure 1 The structural diagram of the strip heat storage body in the cross-sectional view at AA in the middle;

[0024] Figure 3 yes Figure 2 Section view at BB in the view;

[0025] Figure 4 yes Figure 1 The schematic diagram of the structure of the mesh heat storage body in the cross-sectional view at AA in the middle;

[0026] Figure 5 yes Figure 3 Section view at CC in the figure;

[0027] Figure 6 yes Figure 1 A schematic diagram of the top view of the structure;

[0028] Figure 7 yes Figure 6 Section view at DD in the figure;

[0029] Figure 8 yes Figure 7 Schematic diagram of the left view structure of the view;

[0030] Fig. 9 This is the flow curve diagram of the grate cooler of this application;

[0031] Fig.10 This is a temperature curve diagram of the grate cooler of the present application with a peak shift of 1 hour;

[0032] Fig.11 This is the temperature and flow curve of the grate cooler after staggered mixing for 1 hour in this application. DETAILED DESCRIPTION

[0033] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several changes and improvements can also be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0034] Example 1

[0035] This embodiment provides a titanium slag waste gas waste heat utilization system, such as Figure 1-11 As shown, it mainly includes a grate cooling unit 100, a drum 200, an evaporator 300, a superheater 400, an economizer 500 and a control component 600. Among them, the grate cooling unit 100 is used to cool the titanium slag and transmit the high-temperature flue gas formed in the cooling process to the boiler flue 700, which is used to heat the evaporator 300, the superheater 400 and the economizer 500 arranged in the boiler flue 700. The evaporator 300, the superheater 400 and the economizer 500 are connected with the drum 200 to form a heat transfer system for generating superheated steam and transmitting it to the outside. The control component 600 ensures the stable operation of the titanium slag waste gas waste heat utilization system by controlling the operation of the grate cooling unit 100 and the water supply of the drum 200.

[0036] The grate cooling unit 100 is composed of a plurality of grate coolers 110 arranged in parallel. In this embodiment, the grate cooling unit 100 includes two groups of grate coolers 110, which are respectively recorded as the first grate cooler 111 and the second grate cooler 112. The first grate cooler 111 and the second grate cooler 112 transfer heat to the boiler flue 700 through the heat transfer channel 120. In this embodiment, a heat storage body 121 is arranged in the heat transfer channel 120, and the inner layer of the heat storage body 121 is a heat-insulating material, and the outer layer is a refractory material. Figure 2-5 As shown, the heat storage bodies 121 are arranged in a staggered manner in the heat transfer channel 120, and the flow field is evenly mixed and the heat storage is sufficient. During the high-temperature period of the flue gas, the outer surface of the heat storage body 121 is flushed, and the heat storage body 121 absorbs heat and stores energy. During the low-temperature period, the heat storage body 121 releases heat from the inside to the outside through heat conduction and radiation. The enthalpy value and hot air temperature provided by the heat storage body 121 change according to the period, and the cycle is cyclical, which ultimately assists in controlling the waste heat and flue gas energy in a relatively gentle area, and plays a role in stabilizing the flue gas working conditions at the boiler inlet. The heat storage body 121 is a strip body or a mesh body. When the dust in the flue gas is low, a mesh body can be used, and when the dust in the flue gas is high, a strip body can be used.

[0037] The water inlet of the drum 200 is connected to the water outlet of the economizer 500, the downcomer of the drum 200 is connected to the inlet of the evaporator 300, the outlet of the evaporator 300 is connected to the upcomer of the drum 200, and the saturated steam outlet of the drum 200 is connected to the steam inlet of the superheater 400. After receiving the hot water from the economizer 500, the drum 200 transports the hot water to the evaporator 300 to form a steam-water mixture, and the steam-water mixture generated in the evaporator 300 is transported to the drum 200. After steam and water are separated by the drum 200, the separated saturated steam is transported to the superheater 400 to form superheated steam and then output to the outside. In this embodiment, the drum 200 is provided with a water level gauge main pipe 210 and a water level gauge connection header 220. The water level gauge main pipe 210 is connected in series with the header 220 and water level gauges arranged at different positions outside the boiler drum 200 through the water level gauge, and the DCS controller 610 reads the data of the water level gauge main pipe 210. The water level gauge main pipe 210 can make the water level reading of the boiler drum 200 more stable and accurate, which is conducive to controlling the adjustment of the water supply amount of the boiler drum 200 through the DCS controller 610.

[0038] The control component 600 includes a DCS controller 610 and a calorific value detection component 620. In this embodiment, the calorific value detection component 620 is composed of a flue gas flow meter 621 and a flue gas temperature detector 622. Each grate cooler 110 in the grate cooling unit 100 is provided with at least one set of calorific value detection components 620, that is, in this embodiment, the first grate cooler 111 and the second grate cooler 112 are provided with a flue gas flow meter 621 and a flue gas temperature detector 622. The DCS controller 610 is electrically connected to the flue gas flow meter 621 and the flue gas temperature detector 622, collects the flue gas temperature and flue gas flow in each grate cooler 110, and obtains the calorific value in each grate cooler 110 through the flue gas temperature and flue gas flow. At the same time, the DCS controller 610 is electrically connected to the feed water pump of the boiler drum 200 and controls the water supply. The so-called feed water pump of the boiler drum 200 refers to the feed water pump that transports hot water from the economizer 500 to the boiler drum 200.

[0039] The working principle of the titanium slag waste gas waste heat utilization system of the present application is as follows: the titanium slag is transported from the smelting furnace to the first grate cooler 111, the DCS controller 610 first controls the first grate cooler 111 to start, the titanium slag starts to cool in the first grate cooler 111 and transfers heat to the boiler flue 700 through the heat transfer channel 120, and the DCS controller 610 constantly collects data information from the flue gas flow meter 621 and the flue gas temperature detector 622 set on the first grate cooler 111 and generates calorific value. The economizer 500, evaporator 300, and superheater 400 absorb the flue gas heat from the cooling of the titanium slag in the first grate cooler 111 and form a superheated steam production system with the drum 200, and output the superheated steam to the outside through the outlet of the superheater 400. When the DCS controller 610 detects that the calorific value in the first grate cooler 111 is lower than the predetermined value, the second grate cooler 112 is controlled to be turned on. At this time, the titanium slag in the second grate cooler 112 can be the titanium slag output from the same smelting furnace, or the titanium slag input from other smelting furnaces. The high-temperature flue gas generated by cooling the titanium slag in the second grate cooler 112 and the medium- and low-temperature flue gas generated in the first grate cooler 111 at this time are mixed in the heat transfer channel 120 and then transmitted to the boiler flue 700. At the same time, the DCS controller 610 controls the water supply input from the economizer 500 to the drum 200 according to the collected calorific value of the first grate cooler 111 or the average calorific value of the first grate cooler 111 and the second grate cooler 112, so as to ensure that the water supply of the drum 200 matches the calorific value. When more groups of grate coolers 110 are set up in the system due to actual production needs, according to the cooling rate of the titanium slag in the grate cooler 110, when the calorific value collected in the corresponding grate cooler 110 in the DSC system is lower than the preset value, the next grate cooler 110 is turned on to achieve constant output heat and ensure stable operation of the boiler.

[0040] The present invention obtains the staggered operation of the grate cooler and the water supply to the drum according to the heat mean value of the grate cooler unit through the DCS controller, so as to achieve stable output of the waste heat of the titanium slag within a predetermined calorific value range, ensure the stable operation of the waste heat boiler, effectively improve the utilization efficiency of the waste heat, and solve the technical problem of unstable system operation caused by intermittent cooling of the titanium slag and the need to supplement external energy as an auxiliary.

[0041] Example 2

[0042] This embodiment is a method for utilizing the waste heat of titanium slag waste gas formed on the basis of Embodiment 1, and adopts the titanium slag waste gas waste heat utilization system as described in Embodiment 1, including the following steps:

[0043] S1, multiple grate coolers 110 are connected in parallel to form a grate cooling unit 100, and the grate cooling unit 100 is connected to the boiler flue 700 through the heat transfer channel 120. The boiler flue 700 is provided with an evaporator 300, a superheater 400 and an economizer 500, the water outlet of the economizer 500 is connected to the water inlet of the drum 200, the water outlet of the drum 200 is connected to the water inlet of the evaporator 300, the steam outlet of the evaporator 300 is connected to the air inlet of the drum 200, the air outlet of the drum 200 is connected to the air inlet of the superheater 400, and the air outlet of the superheater 400 is connected to an external device and outputs energy.

[0044] S2, titanium slag is transported from the smelting furnace to each grate cooler 110 in the grate cooler unit 100, the DCS controller 610 first controls the first grate cooler 111 to start operation, and the flue gas flow meter 621 and the flue gas temperature detector 622 transmit the parameters to the DCS controller in real time. The DCS controller 610 controls the water supply from the economizer 500 to the boiler drum 200 according to the collected calorific value in the first grate cooler 111.

[0045] S3, when the DCS controller 610 controls the second grate cooler 112 to start when the calorific value collected in the first grate cooler 111 is lower than the predetermined value, the flue gas in the second grate cooler 112 is mixed with the flue gas in the first grate cooler 111 in the heat transfer channel 120 and then passes into the boiler flue 700. At the same time, the DCS controller 610 controls the water supply of the drum 200 according to the average calorific value of the first grate cooler 111 and the second grate cooler 112.

[0046] S4, repeat the procedure of step S3 until the DCS controller 610 turns on the Nth grate cooler 11N.

[0047] In the description of the present application, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0048] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A titanium slag waste gas waste heat utilization system, characterized in that: It comprises a grate cooling unit (100), a boiler drum (200), an evaporator (300), a superheater (400), an economizer (500) and a control component (600); The grate cooler unit (100) is composed of a plurality of grate coolers (110) arranged in parallel, wherein the plurality of grate coolers (110) are respectively recorded as a first grate cooler (111), ..., an Nth grate cooler (11N), wherein N is a natural number greater than 1, and the plurality of grate coolers (110) arranged in parallel transfer waste heat to a waste heat boiler flue (700) through a heat transfer channel (120), and the evaporator (300), the superheater (400) and the economizer (500) is arranged in the boiler flue (700), the water outlet of the economizer (500) is communicated with the water inlet of the drum (200), the water outlet of the drum (200) is communicated with the water inlet of the evaporator (300), the steam outlet of the evaporator (300) is communicated with the air inlet of the drum (200), the air outlet of the drum (200) is communicated with the air inlet of the superheater (400), and the air outlet of the superheater (400) is communicated with an external device; The control component (600) comprises a DCS controller (610) and a calorific value detection component (620), wherein each of the grate coolers (110) is provided with the calorific value detection component (620), and the DCS controller (610) determines the start time of the Nth grate cooler and the water supply amount of the boiler drum (200) according to the collected average calorific values ​​of the first grate cooler (111) to the N-1th grate cooler.

2. The titanium slag waste gas waste heat utilization system according to claim 1 is characterized in that: The number of the grate coolers (110) in the grate cooler unit (100) is 2-5.

3. The titanium slag waste gas waste heat utilization system according to claim 1, characterized in that: A heat storage body (121) is provided in the heat transfer channel (120); the inner layer of the heat storage body (121) is a heat-insulating material, and the outer layer is a refractory material.

4. The titanium slag waste gas waste heat utilization system according to claim 3 is characterized in that: The heat storage body (121) is a strip-shaped body or a mesh-shaped body, and a plurality of the heat storage bodies (121) are arranged in a staggered manner in front and back in the heat transfer channel (120).

5. The titanium slag waste gas waste heat utilization system according to claim 1, characterized in that: The calorific value detection component (620) comprises a smoke flow meter (621) and a smoke temperature detector (622).

6. The titanium slag waste gas waste heat utilization system according to claim 1, characterized in that: The boiler drum (200) is provided with a water level gauge main pipe (210) and a water level gauge connection header (220); the water level gauge main pipe (210) is connected in series with water level gauges arranged at different positions outside the boiler drum (200) through the water level gauge connection header (220); the water level gauge main pipe (210) measures the water level of the boiler drum (200) and transmits the water level to the DCS controller (610).

7. A method for utilizing waste heat from titanium slag waste gas, characterized in that: The titanium slag waste gas waste heat utilization system as claimed in any one of claims 1 to 6 comprises the following steps: S1, connecting a plurality of grate coolers (110) in parallel to form a grate cooling unit (100), wherein the grate cooling unit (100) is connected to a boiler flue (700) via a heat transfer channel (120), wherein an evaporator (300), a superheater (400) and an economizer (500) are arranged in the boiler flue (700), wherein a water outlet of the economizer (500) is connected to a water inlet of a drum (200), wherein the water outlet of the drum (200) is connected to a water inlet of the evaporator (300), wherein a steam outlet of the evaporator (300) is connected to an air inlet of the drum (200), wherein an air outlet of the drum (200) is connected to an air inlet of the superheater (400), and wherein an air outlet of the superheater (400) is connected to an external device; S2, titanium slag is transported from the smelting furnace to each of the grate coolers (110) in the grate cooler unit (100), the DCS controller (610) first controls the first grate cooler (111) to start operation, the flue gas flow meter (621) and the flue gas temperature detector (622) transmit parameters to the DCS controller (610) in real time, and the DCS controller (610) controls the amount of water supplied from the economizer (500) to the boiler drum (200) according to the calorific value collected in the first grate cooler (111); S3, when the DCS controller (610) controls the second grate cooler (112) to start when the calorific value collected in the first grate cooler (111) is lower than a predetermined value, the flue gas in the second grate cooler (112) is mixed with the flue gas in the first grate cooler (111) in the heat transfer channel (120) and then introduced into the boiler flue (700), and at the same time, the DCS controller (610) controls the water supply of the boiler drum (200) according to the average of the calorific values ​​of the first grate cooler (111) and the second grate cooler (112) collected and calculated; S4, repeat the procedure of step S3 until the DCS controller (610) turns on the Nth grate cooler (11N).

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