CN112337132A - Ferrous sulfate crystal separation treatment method for titanium dioxide production by sulfuric acid process - Google Patents
Ferrous sulfate crystal separation treatment method for titanium dioxide production by sulfuric acid process Download PDFInfo
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Abstract
The invention discloses a ferrous sulfate crystal separation treatment method for sulfuric acid process titanium dioxide production, which comprises the following steps: s1, introducing the titanium liquid to be cooled, introducing a cold circulating liquid into a heat exchange pipeline, crystallizing and separating; s2, introducing the titanium liquid to be cooled, introducing circulating liquid at 55-75 ℃ into a heat exchange pipeline until ferrous sulfate crystals are dissolved, and then cooling the circulating liquid by the heat exchange pipeline, crystallizing and separating; repeating the step of S2; the cold circulating liquid is water, and comprises water with the temperature of 20-30 ℃ and water with the temperature of 8-15 ℃; specifically, water with the temperature of 20-30 ℃ is introduced into the heat exchange pipeline to cool the titanium liquid to be cooled to 30-40 ℃, and then water with the temperature of 8-15 ℃ is introduced into the heat exchange pipeline to continuously cool the titanium liquid to be cooled to 20-25 ℃. The invention has the advantages of saving manpower, reducing production cost, avoiding splashing of acid washing liquid in the manual cleaning process and simultaneously improving the recovery rate of titanium dioxide in the freezing and crystallizing link.
Description
Technical Field
The invention relates to the technical field of titanium dioxide production by a sulfuric acid method. More specifically, the invention relates to a ferrous sulfate crystallization separation treatment method for titanium dioxide production by a sulfuric acid method.
Background
In the production of titanium white by a sulfuric acid method, ferrous sulfate crystallization in titanium liquid mainly comprises two processes of freezing crystallization and vacuum crystallization, wherein a common method for separating ferrous sulfate by freezing crystallization in the industry comprises the following steps: the settled titanium liquid with the temperature of about 50 ℃ is put into a freezing pot with a heat exchange coil pipe and mechanical stirring, when the titanium liquid put into the pot reaches the specified liquid level, the feeding is stopped, and the mechanical stirring is normally started; introducing cold water with the temperature of about 12 ℃ into the heat exchange coil pipe to cool the titanium liquid in the freezing pot to about 22 ℃; under the continuous stirring, a large amount of ferrous sulfate crystals are separated out to form a uniform solid-liquid mixture with the titanium liquid, so that the requirement of ferrous sulfate crystal separation is met; discharging a solid-liquid mixture of the titanium liquid and the ferrous sulfate crystals in the freezing pot, flowing into a centrifuge for solid-liquid separation, washing ferrous sulfate solids through a proper amount of cold water to be clean into byproducts to be packaged and sold, mixing the titanium-containing washing liquid into the separated titanium liquid, and sending into the next procedure for processing to finish the whole crystallization separation operation of the ferrous sulfate.
In the process of separating ferrous sulfate by freezing crystallization, a freezing pot for discharging a solid-liquid mixture of titanium liquid and ferrous sulfate crystallization is finished, and a layer of compact ferrous sulfate crystallization is firmly adhered to the outer wall of the heat exchange coil pipe, so that the compact ferrous sulfate crystallization is a heat conduction barrier layer, and the coil pipe can be cleaned to recover the good heat exchange performance. In the prior art, the cleaning operation of the coil pipe and the boiler wall mainly comprises two steps, firstly, a small amount of cold water is used for sprinkling ferrous iron of the coil pipe and the boiler wall to recover titanium components adhered to the ferrous iron and the boiler wall and directly mixed into cooling titanium liquid to be separated, the step can increase the recovery rate of titanium, but also reduce the concentration of titanium dioxide in the titanium liquid to be separated; secondly, clean water with the pressure of 0.25MPa is used for cleaning compact ferrous sulfate crystals firmly adhered to the coil pipe, and the operation is carried out on average every ton of TiO produced2It takes 10 minutes, and the water consumption is 0.6m3Increasing the discharge amount of ferrous sulfate heptahydrate by 100kg, and simultaneously losing the recovery rate of titanium dioxide; cleaning the coil pipe, adjusting various valves to required conditions, pumping the settled titanium liquid again, and starting a new round of freezing and crystallizing operation. The cleaning mode reduces the content of titanium dioxide in the titanium liquid to be separated, loses titanium dioxide adhered to ferrous sulfate crystals on the coil pipe to reduce the recovery rate of the titanium dioxide, splashed washing acid water easily hurts people and corrodes surrounding equipment and structures, acid mist chokes people, pollutant discharge amount is increased, the labor intensity of operators is high, and the like. However, no relevant solutions or solutions have been reported or disclosed so far.
Disclosure of Invention
An object of the present invention is to solve at least the above problems and to provide a method for separating ferrous sulfate crystals in titanium white production by sulfuric acid process, which can conveniently and rapidly remove a layer of ferrous sulfate crystals adhered to the outer wall of a heat exchange coil after cooling a titanium liquid to be cooled, completely omit the conventional operation of manually cleaning the heat exchange coil of a freezing pot to recover the heat exchange performance, save manpower, reduce the production cost, improve the recovery rate of titanium dioxide in the freezing crystallization process, avoid splashing of an acid cleaning solution in the manual cleaning process, greatly reduce corrosion of equipment and components around the freezing pot, and eliminate the accident that acidic washing water splashes to hurt people.
To achieve these objects and other advantages in accordance with the present invention, there is provided a method for separating ferrous sulfate crystals in the production of titanium dioxide by a sulfuric acid process, comprising:
s1, introducing the titanium liquid to be cooled, introducing a cold circulating liquid into a heat exchange pipeline, crystallizing and separating;
s2, introducing the titanium liquid to be cooled, introducing circulating liquid at 55-75 ℃ into a heat exchange pipeline until ferrous sulfate crystals are dissolved, and then cooling the circulating liquid by the heat exchange pipeline, crystallizing and separating;
the above step S2 is repeated.
Preferably, the temperature of the cold circulating liquid is 8-15 ℃.
Preferably, the cold circulating liquid is water.
Preferably, the cold circulation fluid includes: water at 20-30 deg.C and water at 8-15 deg.C; specifically, water with the temperature of 20-30 ℃ is introduced into a heat exchange pipeline to cool the titanium liquid to be cooled to 30-40 ℃, and water with the temperature of 8-15 ℃ is introduced into the heat exchange pipeline to continuously cool the titanium liquid to be cooled to 20-25 ℃ so as to separate out ferrous sulfate crystals.
Preferably, the heat exchange tubes are coils.
Preferably, the flow rate of the cold circulating liquid is as follows: 4.0-4.8 m/s.
Preferably, the flow rate of the circulating liquid at the temperature of 55-75 ℃ is as follows: 5.0-6.0 m/s.
Preferably, the content of ferrous sulfate in the introduced titanium liquid to be cooled is not more than 400 g/L.
Preferably, the height of the coil between each layer is 80 mm.
Preferably, the S1 and S2 steps are performed in a freezing pan, the freezing pan including:
the top of the pot body is provided with a liquid inlet, and the bottom of the pot body is provided with a liquid outlet;
the coil pipe is arranged in the pot body, one end of the coil pipe extends upwards out of the pot body and is rotatably connected with the pot body, and the other end of the coil pipe is connected with a water outlet pipe and is rotatably and hermetically connected with the water outlet pipe; one end of the coil pipe extending out of the pot body is rotatably and hermetically connected with a water inlet pipe, and the water outlet pipe penetrates through the top of the pot body and extends out of the pot body;
the motor assembly is arranged above the freezing pot and comprises a vertical motor, a first gear coaxially and fixedly connected with an output shaft of the motor and a horizontal second gear meshed with the first gear, and the second gear is coaxially and fixedly connected with one end of the coil pipe, which is positioned outside the pot body;
the scraping component is arranged in the pot body and comprises a vertical scraping plate and a pair of supporting rods which are respectively arranged at the upper side and the lower side of the scraping plate; the scraper is positioned outside the coil and close to the outer wall of the coil, and the height of the scraper is greater than that of the coil; one end of each supporting rod penetrates through the pot body and is rotatably connected with the pot body, the other end of each supporting rod is rotatably connected with a vertical supporting plate, the top of each vertical supporting plate is fixedly connected with the inner wall of the top of the pot body, threads are arranged on the outer wall of each supporting rod, sliders are coaxially screwed on the threads, and one surfaces, opposite to the sliders, are fixedly connected with corresponding end portions of the scrapers.
The invention at least comprises the following beneficial effects:
firstly, the titanium liquid to be cooled is added into the freezing pot, and the circulating hot water is introduced into the heat exchange coil, so that ferrous sulfate crystals bonded on the heat exchange coil can be dissolved, the heat exchange efficiency and the service life of the heat exchange coil are improved, the operation of recovering the heat exchange performance of the freezing pot by manually cleaning the heat exchange coil in the prior art is completely omitted, the labor is saved, and the production cost is reduced; the splashing of the acid washing liquid in the manual cleaning process is avoided, the corrosion of the peripheral equipment and components of the freezing pot is greatly reduced, and the accident that the acidic washing water splashes to hurt people is eliminated.
Secondly, the invention firstly uses the circulating water with the temperature of 20-30 ℃ for the first cooling and then uses the circulating cold water with the temperature of 8-15 ℃ for the second cooling, thereby saving the consumption of the circulating water and reducing the production cost.
Thirdly, the invention adopts the titanium liquid to be cooled and the circulating hot water to dissolve the ferrous sulfate crystals adhered on the heat exchange coil, compared with the prior method for cleaning the heat exchange coil of the freezing pot to remove the ferrous sulfate crystals, the invention avoids the dilution of the titanium liquid to be separated caused by the ferrous sulfate crystals on the cleaning coil recovering the titanium adhered on the ferrous sulfate crystals, thereby reducing the condition of reducing the concentration of the titanium dioxide in the titanium liquid to be separated and simultaneously improving the recovery rate of the titanium dioxide in the freezing crystallization link.
Fourthly, the heat exchange coil of the freezing pot does not need to be cleaned, so that the problems that ferrous sulfate for cleaning and dissolving the outer wall of the heat exchange coil is discharged to environment-friendly treatment and the consumption of the environment-friendly treatment is increased do not exist.
Fifthly, the motor assembly and the coil pipe are designed, and the coil pipe is driven to rotate by the motor assembly, so that the coil pipe can play a role in stirring, and titanium liquid in the freezing pot is stirred to accelerate heat exchange; scrape the material subassembly through the design, can utilize the rotation of coil pipe when the titanium liquid cooling or get rid of the ferrous sulfate crystallization on the coil pipe, let the scraper blade strike off the ferrous sulfate crystallization on the coil pipe outer wall, can save operating time, improve the heat exchange efficiency of coil pipe.
And sixthly, the distance between the scraping plate and the outer wall of the coil pipe can be adjusted according to the actual production condition by designing the thread and the sliding block on the support rod, so that the scraping effect of the scraper is improved.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention.
Drawings
Fig. 1 is a schematic structural diagram of a freezing pan according to one embodiment of the present invention;
fig. 2 is a top view of a-a in fig. 1.
Reference numerals: 1-a pot body; 2-a coil pipe; 3-a liquid inlet pipe; 4-water outlet pipe; 5-water inlet pipe; 6-a liquid outlet pipe; 7-a motor; 8-a first gear; 9-a second gear; 10-a scaffold; 11-a support plate; 12-a strut; 13-a thread; 14-a slide block; 15-scraper.
Detailed Description
The present invention is further described in detail below with reference to examples so that those skilled in the art can practice the invention with reference to the description.
< example 1>
S1, introducing the titanium liquid to be cooled, introducing a cold circulating liquid into a heat exchange pipeline, crystallizing and separating;
s2, introducing the titanium liquid to be cooled, introducing circulating liquid at 55-75 ℃ into a heat exchange pipeline until ferrous sulfate crystals are dissolved, and then cooling the circulating liquid by the heat exchange pipeline, crystallizing and separating;
repeating the step S2;
specifically, the temperature of the titanium liquid to be cooled is 50 ℃, the settled titanium liquid is introduced into a freezing pot with a heat exchange coil and mechanical stirring, feeding is stopped when the titanium liquid in the pot reaches a specified liquid level, and the mechanical stirring is normally started, wherein the volume of the titanium liquid to be cooled is 13 cubic meters; introducing cold circulating water with the temperature of 12 ℃ into the heat exchange coil pipe to cool the titanium liquid in the freezing pot to 22 ℃, separating out a large amount of ferrous sulfate crystals in the freezing pot under the continuous stirring, and forming a uniform solid-liquid mixture by the large amount of ferrous sulfate crystals and the cooled titanium liquid to meet the requirement of ferrous sulfate crystal separation; discharging a solid-liquid mixture of titanium liquid and ferrous sulfate crystals in a freezing pot, flowing into a centrifuge for solid-liquid separation, washing ferrous sulfate solids by using a proper amount of cold water to obtain a byproduct, packaging the byproduct for later sale, mixing titanium-containing washing liquid into the separated titanium liquid to obtain an intermediate product titanium liquid, and feeding the intermediate product titanium liquid into the next working procedure for processing, wherein the volume of the cold water for washing the ferrous sulfate solids is 1.2-1.8% of the volume of the separated titanium liquid, and the volume of the intermediate product titanium liquid is 10 cubic meters; the method comprises the steps of enabling titanium liquid to be cooled to reach a normal liquid level through the titanium liquid to be cooled in an evacuated freezing pot, starting stirring, and introducing circulating liquid of 55-75 ℃ into a heat exchange coil, wherein the circulating liquid can be water or some neutral ionic liquids, in the embodiment, the circulating liquid is thermal circulating water, the temperature of the thermal circulating water is 70 ℃, and the thermal circulating water of 70 ℃ is continuously introduced to the heat exchange coil under the condition of continuous stirring to be crystallized and dissolved in ferrous sulfate on the heat exchange coil; stopping introducing hot circulating water, balancing the temperature of hot water in the heat exchange coil and the temperature of titanium liquid in the freezing pot, switching a valve to introduce cold circulating water with the temperature of 12 ℃ into the heat exchange coil, and starting a new round of freezing crystallization operation;
the height between each layer of the heat exchange coil is 80mm, the flow rate of the cold circulating water is 4.0-4.8m/s, the flow rate of the hot circulating water is 5.0-6.0m/s, and the content of ferrous sulfate in the titanium liquid to be cooled is not more than 400 g/L.
< example 2>
S1, introducing the titanium liquid to be cooled, introducing a cold circulating liquid into a heat exchange pipeline, crystallizing and separating;
s2, introducing the titanium liquid to be cooled, introducing circulating liquid at 55-75 ℃ into a heat exchange pipeline until ferrous sulfate crystals are dissolved, and then cooling the circulating liquid by the heat exchange pipeline, crystallizing and separating;
repeating the step S2;
specifically, the temperature of the titanium liquid to be cooled is 50 ℃, the settled titanium liquid is introduced into a freezing pot with a heat exchange coil and mechanical stirring, feeding is stopped when the titanium liquid in the pot reaches a specified liquid level, and the mechanical stirring is normally started, wherein the volume of the titanium liquid to be cooled is 13 cubic meters; introducing cold circulating water with the temperature of 12 ℃ into the heat exchange coil pipe to cool the titanium liquid in the freezing pot to 22 ℃, separating out a large amount of ferrous sulfate crystals in the freezing pot under the continuous stirring, and forming a uniform solid-liquid mixture by the large amount of ferrous sulfate crystals and the cooled titanium liquid to meet the requirement of ferrous sulfate crystal separation; discharging a solid-liquid mixture of titanium liquid and ferrous sulfate crystals in a freezing pot, flowing into a centrifuge for solid-liquid separation, washing ferrous sulfate solids by using a proper amount of cold water to obtain a byproduct, packaging the byproduct for later sale, mixing titanium-containing washing liquid into the separated titanium liquid to obtain an intermediate product titanium liquid, and feeding the intermediate product titanium liquid into the next working procedure for processing, wherein the volume of the cold water for washing the ferrous sulfate solids is 1.2-1.8% of the volume of the separated titanium liquid, and the volume of the intermediate product titanium liquid is 10 cubic meters; the method comprises the steps of enabling titanium liquid to be cooled to reach a normal liquid level through the titanium liquid to be cooled in an evacuated freezing pot, starting stirring, and introducing circulating liquid of 55-75 ℃ into a heat exchange coil, wherein the circulating liquid can be water or some neutral ionic liquids, in the embodiment, the circulating liquid is hot circulating water, the temperature of the hot circulating water is 60 ℃, and under the condition of continuous stirring, 60 ℃ hot circulating water is continuously introduced to the heat exchange coil to be dissolved in ferrous sulfate crystals; stopping introducing hot circulating water, balancing the temperature of hot water in the heat exchange coil and the temperature of titanium liquid in the freezing pot, switching a valve to introduce cold circulating water with the temperature of 12 ℃ into the heat exchange coil, and starting a new round of freezing crystallization operation;
the height between each layer of the heat exchange coil is 80mm, the flow rate of the cold circulating water is 4.0-4.8m/s, the flow rate of the hot circulating water is 5.0-6.0m/s, and the content of ferrous sulfate in the titanium liquid to be cooled is not more than 400 g/L.
< example 3>
S1, introducing the titanium liquid to be cooled, introducing a cold circulating liquid into a heat exchange pipeline, crystallizing and separating; the cold circulating liquid comprises: water at 20-30 deg.C and water at 8-15 deg.C; specifically, water with the temperature of 20-30 ℃ is introduced into a heat exchange pipeline to cool the titanium liquid to be cooled to 30-40 ℃, then water with the temperature of 8-15 ℃ is introduced into the heat exchange pipeline to continuously cool the titanium liquid to be cooled to 20-25 ℃, and ferrous sulfate crystals are separated out;
s2, introducing the titanium liquid to be cooled, introducing circulating liquid at 55-75 ℃ into a heat exchange pipeline until ferrous sulfate crystals are dissolved, and then cooling the circulating liquid by the heat exchange pipeline, crystallizing and separating;
repeating the step S2;
specifically, the temperature of the titanium liquid to be cooled is 50 ℃, the settled titanium liquid is introduced into a freezing pot with a heat exchange coil and mechanical stirring, feeding is stopped when the titanium liquid in the pot reaches a specified liquid level, and the mechanical stirring is normally started, wherein the volume of the titanium liquid to be cooled is 13 cubic meters; introducing water with the temperature of 25 ℃, namely normal-temperature water into the heat exchange coil, cooling the titanium liquid to be cooled to 36 ℃, then switching a valve, introducing cold circulating water with the temperature of 12 ℃ into the heat exchange coil, cooling the titanium liquid in the freezing pot to 22 ℃, separating out a large amount of ferrous sulfate crystals in the freezing pot under continuous stirring, and forming a uniform solid-liquid mixture by the large amount of ferrous sulfate crystals and the cooled titanium liquid to meet the requirement of ferrous sulfate crystal separation; discharging a solid-liquid mixture of titanium liquid and ferrous sulfate crystals in a freezing pot, flowing into a centrifuge for solid-liquid separation, washing ferrous sulfate solids by using a proper amount of cold water to obtain a byproduct, packaging the byproduct for later sale, mixing titanium-containing washing liquid into the separated titanium liquid to obtain an intermediate product titanium liquid, and feeding the intermediate product titanium liquid into the next working procedure for processing, wherein the volume of the cold water for washing the ferrous sulfate solids is 1.2-1.8% of the volume of the separated titanium liquid, and the volume of the intermediate product titanium liquid is 10 cubic meters; the method comprises the steps of enabling titanium liquid to be cooled to reach a normal liquid level through the titanium liquid to be cooled in an evacuated freezing pot, starting stirring, and introducing circulating liquid of 55-75 ℃ into a heat exchange coil, wherein the circulating liquid can be water or some neutral ionic liquids, in the embodiment, the circulating liquid is thermal circulating water, the temperature of the thermal circulating water is 70 ℃, and the thermal circulating water of 70 ℃ is continuously introduced to the heat exchange coil under the condition of continuous stirring to be crystallized and dissolved in ferrous sulfate on the heat exchange coil; stopping introducing hot circulating water, balancing the temperature of hot water in the heat exchange coil and the temperature of titanium liquid in the freezing pot, switching a valve to introduce cold circulating water with the temperature of 12 ℃ into the heat exchange coil, and starting a new round of freezing crystallization operation;
the height between each layer of the heat exchange coil is 80mm, the flow rate of the cold circulating water is 4.0-4.8m/s, the flow rate of the hot circulating water is 5.0-6.0m/s, and the content of ferrous sulfate in the titanium liquid to be cooled is not more than 400 g/L;
by using the technical scheme, the beneficial effects are that the titanium liquid to be cooled is cooled to 30-40 ℃ by using water with the temperature of 20-30 ℃, namely normal temperature water, and then the water with the temperature of 8-15 ℃ is introduced into the heat exchange pipeline, so that the titanium liquid to be cooled is continuously cooled to 20-25 ℃, ferrous sulfate crystals are separated out, the use amount of cold circulating water can be effectively reduced, and the cost is reduced.
< example 4>
S1, introducing the titanium liquid to be cooled, introducing a cold circulating liquid into a heat exchange pipeline, crystallizing and separating;
s2, introducing the titanium liquid to be cooled, introducing circulating liquid at 55-75 ℃ into a heat exchange pipeline until ferrous sulfate crystals are dissolved, and then cooling the circulating liquid by the heat exchange pipeline, crystallizing and separating;
repeating the step S2;
specifically, the temperature of the titanium liquid to be cooled is 50 ℃, the settled titanium liquid is introduced into a freezing pot with a heat exchange coil and mechanical stirring, feeding is stopped when the titanium liquid in the pot reaches a specified liquid level, and the mechanical stirring is normally started, wherein the volume of the titanium liquid to be cooled is 13 cubic meters; introducing water with the temperature of 25 ℃, namely normal-temperature water into the heat exchange coil, cooling the titanium liquid to be cooled to 36 ℃, then switching a valve, introducing cold circulating water with the temperature of 12 ℃ into the heat exchange coil, cooling the titanium liquid in the freezing pot to 22 ℃, separating out a large amount of ferrous sulfate crystals in the freezing pot under continuous stirring, and forming a uniform solid-liquid mixture by the large amount of ferrous sulfate crystals and the cooled titanium liquid to meet the requirement of ferrous sulfate crystal separation; discharging a solid-liquid mixture of titanium liquid and ferrous sulfate crystals in a freezing pot, flowing into a centrifuge for solid-liquid separation, washing ferrous sulfate solids by using a proper amount of cold water to obtain a byproduct, packaging the byproduct for later sale, mixing titanium-containing washing liquid into the separated titanium liquid to obtain an intermediate product titanium liquid, and feeding the intermediate product titanium liquid into the next working procedure for processing, wherein the amount of the cold water for washing the ferrous sulfate solids is 1.2-1.8% of the volume of the separated titanium liquid, and the volume of the intermediate product titanium liquid is 10 cubic meters; introducing titanium liquid to be cooled into an evacuated freezing pot until the titanium liquid to be cooled reaches a normal liquid level, starting stirring, and introducing circulating liquid at 55-75 ℃ into a heat exchange coil, wherein the circulating liquid is specifically hot circulating water, the temperature of the hot circulating water is 70 ℃, and the hot circulating water at 70 ℃ is continuously introduced under the condition of continuous stirring until ferrous sulfate crystals on the heat exchange coil are dissolved; stopping introducing hot circulating water, balancing the temperature of hot water in the heat exchange coil and the temperature of titanium liquid in the freezing pot, switching a valve to introduce cold circulating water with the temperature of 12 ℃ into the heat exchange coil, and starting a new round of freezing crystallization operation;
the height between each layer of the heat exchange coil is 80mm, the flow rate of the cold circulating water is 4.0-4.8m/s, the flow rate of the hot circulating water is 5.0-6.0m/s, and the content of ferrous sulfate in the titanium liquid to be cooled is not more than 400 g/L;
the S1 and the S2 steps are performed in a freezer pot comprising:
the pot comprises a pot body 1, wherein a liquid inlet is formed in the top of the pot body 1, and a liquid outlet is formed in the bottom of the pot body; the liquid inlet is coaxially connected with a liquid inlet pipe 3, and the liquid outlet is coaxially connected with a liquid outlet pipe 6;
the coil pipe 2 is arranged in the pot body 1, one end of the coil pipe 2 extends upwards out of the pot body 1 and is rotationally connected with the pot body 1, and the other end of the coil pipe 2 is connected with a water outlet pipe 4 and is rotationally and hermetically connected with the water outlet pipe 4; one end of the coil pipe 2 extending out of the pot body 1 is rotatably and hermetically connected with a water inlet pipe 5, and the water outlet pipe 4 penetrates through the top of the pot body 1 and extends out of the pot body 1; wherein the coil 2 is located in the center of the freezer pan;
the motor assembly is arranged above the freezing pot and comprises a vertical motor 7, a first gear 8 coaxially and fixedly connected with an output shaft of the motor 7 and a horizontal second gear 9 meshed with the first gear 8, the second gear 9 is coaxially and fixedly connected with one end of the coil pipe 2, which is positioned outside the pot body 1, and the motor 7 drives the first gear 8, the second gear 9 and the coil pipe 2 to rotate; the motor 7 is fixed at the top of the freezing pot through an H-shaped bracket 10, and the motor 7 is fixedly arranged on a horizontal plate of the H-shaped bracket;
the scraping component is arranged in the pot body 1 and comprises a vertical scraping plate 15 and a pair of supporting rods 12 which are respectively arranged at the upper side and the lower side of the scraping plate 15; the scraper 15 is positioned outside the coil 2 and close to the outer wall of the coil 2, and the height of the scraper 15 is greater than that of the coil 2, so that the scraper 15 can conveniently scrape ferrous sulfate crystals on the outer wall of the coil 2; one end of the supporting rod 12 penetrates through the pot body 1 and is rotationally connected with the pot body 1, the other end of the supporting rod is rotationally connected with a vertical supporting plate 11, the top of the vertical supporting plate 11 is fixedly connected with the inner wall of the top of the pot body 1, and the supporting rod 12 is supported to rotate; the outer wall of each supporting rod 12 is provided with a thread 13, the thread 13 is coaxially screwed with a sliding block 14, one opposite surface of each pair of sliding blocks 14 is fixedly connected with one corresponding end part of the scraper 15, the sliding blocks 14 on the supporting rods 12 can move forward or backward by rotating the supporting rods 12, and then the scraper 15 is driven to move forward or backward, the distance between the scraper 15 and the outer wall of the coil 2 can be adjusted, and in the actual use process, the distance between the scraper 15 and the coil 2 can be adjusted according to the situation;
in the embodiment, in the specific use process, according to the actual use condition, the support rod 12 is rotated to adjust the distance between the scraper 15 and the outer wall of the coil 2 to a proper position, then the titanium liquid to be cooled is added into the freezing pot to a specified liquid level, the motor 7 is started to drive the coil 2 to rotate, then cold circulating water is introduced into the coil 2, and ferrous sulfate crystals are gradually separated out from the titanium liquid to be cooled; by adopting the technical scheme, the beneficial effects are that the coil pipe 2 is driven to rotate by the motor 7 component through the design of the motor 7 component and the coil pipe 2, so that the coil pipe 2 can play a role in stirring, titanium liquid in the freezing pot is stirred, and the heat exchange of the titanium liquid is accelerated; by designing the scraping component, when the titanium liquid is cooled or ferrous sulfate crystals on the coil 2 are removed, the scraper 15 scrapes the ferrous sulfate crystals on the outer wall of the coil 2 by utilizing the rotation of the coil 2, so that the operation time can be saved, and the heat exchange efficiency of the coil 2 is improved; through design screw thread 13 and slider 14 on branch 12, can be according to the actual production condition, adjust the distance between scraper blade 15 and the coil pipe 2 outer wall, improve its scraper effect, and then improve heat exchange efficiency.
< comparative example 1>
The method adopts a traditional cleaning mode to remove ferrous sulfate crystals on the heat exchange coil, and comprises the following specific steps:
s1, pumping the titanium liquid to be cooled at about 50 ℃ after being settled into a freezing pot with a heat exchange coil and mechanical stirring, stopping feeding when the titanium liquid in the pot reaches a specified liquid level, and normally starting the mechanical stirring, wherein the volume of the titanium liquid to be cooled is 13 cubic meters;
s2, circulating cold water with the temperature of about 12 ℃ is introduced into the heat exchange coil pipe to cool the titanium liquid in the freezing pot to about 22 ℃; under continuous stirring, a large amount of ferrous sulfate ions are crystallized and separated out to form a uniform solid-liquid mixture with the titanium liquid, so that the requirement of ferrous crystallization separation is met, and the separated titanium liquid is obtained;
s3, discharging a solid-liquid mixture of the separated titanium liquid and ferrous sulfate crystals, allowing the mixture to flow into a centrifuge for solid-liquid separation, washing ferrous sulfate solids with a proper amount of cold water to obtain a byproduct, packaging the byproduct for sale, wherein the amount of the cold water is 1.2-1.8% of the volume of the separated titanium liquid, and the titanium-containing washing liquid is mixed into the separated titanium liquid to obtain a mixed titanium liquid, so that the whole crystallization separation operation of the ferrous sulfate is completed;
s4, discharging the separated titanium liquid and ferrous sulfate crystal solid-liquid mixture, firmly bonding a layer of compact ferrous sulfate crystal with the thickness of about 5mm on the outer wall of a heat exchange coil, sprinkling a small amount of cold water on the ferrous sulfate crystal on the coil and recovering the titanium component adhered to the ferrous sulfate crystal by the wall of the pot, directly mixing the titanium component into the mixed titanium liquid in S3 to obtain an intermediate product titanium liquid, and sending the intermediate product titanium liquid to the next procedure for processing, wherein the amount of the cold water is 1.5% of the volume of the separated titanium liquid, and the volume of the intermediate product titanium liquid is 10 cubic meters; cleaning compact ferrous sulfate crystals firmly adhered to the coil pipe by using clean water with the pressure of 0.25MPa until the ferrous sulfate crystals on the heat exchange coil pipe are completely removed, and discharging waste liquid generated by cleaning to an environment-friendly place;
s5, cleaning the coil pipe, adjusting various valves to required conditions, pumping the settled titanium liquid to be cooled again, and starting a new round of freezing crystallization operation;
the height between each layer of the heat exchange coil is 80mm, the flow rate of the circulating cold water is 4.0-4.8m/s, and the content of ferrous sulfate in the titanium liquid to be cooled is not more than 400 g/L.
< comparative example 2>
The procedure of example 1 was repeated except that only the titanium solution to be cooled was introduced and the hot circulating water was not introduced.
< Experimental example >
1. Determination of titanium dioxide content in titanium liquid
The method comprises the following steps: the determination is carried out by adopting an aluminum sheet reduction method and a ferric salt redox titration method, and specifically comprises the following steps:
saturated sodium bicarbonate solution: add about 10g of sodium bisulfate to 90ml of water;
ammonium thiocyanate indicator: dissolving 24.5g ammonium bisulfate in 80ml hot water, filtering, cooling to room temperature, diluting to 100ml, and storing in a sealed dark bottle;
taking 10ml of titanium liquid to be measured, placing the titanium liquid in a volumetric flask of 100ml, and diluting the titanium liquid to the scale mark by using distilled water; taking 10ml of a sample with constant volume into a 500ml conical flask, adding 20ml of 20% sulfuric acid, 30ml of concentrated hydrochloric acid and 2g of aluminum sheet, installing a liquid seal tube, plugging a rubber plug, adding a sodium bicarbonate saturated solution into the liquid seal tube to about two thirds of the volume of the liquid seal tube, heating with an electric furnace on a small fire, removing a heat source when the reaction is severe, continuing to heat when the reaction is slow, removing hydrogen in a clean solution, leaving the heat source when the solution is clear, cooling to room temperature with running water, and adding the sodium bicarbonate saturated solution at any time in the cooling process; after cooling, removing the liquid seal tube, quickly pouring the saturated solution of sodium bicarbonate in the liquid seal tube into a conical flask, immediately titrating to nearly colorless with 0.1mol/L ammonium ferric sulfate standard solution, adding 2ml of 40% ammonium thiocyanate indicator, continuously titrating to a light brown yellow end point, and recording the using amount of the ammonium ferric sulfate standard solution;
titanium dioxide content (g/L) 1000 × (N × V × 0.0799 × V)1)/(V2×V3)；
The molar concentration of the N-ammonium ferric sulfate standard solution;
consumption of milliliter of the V-ferric ammonium sulfate standard solution;
V1volumetric flask volume in milliliters;
V2-the number of ml of test solution after dilution;
V3-milliliters of original solution;
0.0799-titanium dioxide millimolar mass.
Sample preparation: the titanium liquid to be cooled and the intermediate product titanium liquid in the examples 1-4 and the comparative examples 1-2 are taken for measurement, the measurement is carried out three times for each example and comparative example, the average value is taken, and the experimental data are shown in the tables 2 and 3.
2. Determination of total iron content in titanium liquid
The method comprises the following steps:
(1) determination of trivalent titanium in titanium liquid
Taking 10ml of titanium liquid to be measured, injecting the titanium liquid into a 500ml conical flask, diluting the titanium liquid to 50ml by using 1:20 sulfuric acid, adding 2ml of 40% ammonium thiocyanate indicator, titrating the titanium liquid to a light brown yellow end point by using 0.1mol/L ferric ammonium sulfate standard solution, and recording the milliliter number of the consumed ferric ammonium sulfate standard solution;
(2) the ferrous sulfate content is determined by potassium permanganate redox titration
Taking 10ml of titanium liquid to be measured, adding the titanium liquid into a 100ml volumetric flask, and diluting the titanium liquid to a scale mark by using distilled water; placing the sample 1oml with constant volume in a 250ml conical flask, adding 20ml of 20% sulfuric acid and 20ml of distilled water, titrating to be micro-powder red by using 0.2mol/L potassium permanganate standard solution, and taking the end point after the solution does not disappear in half a minute;
total iron content (g/L) {1000 × (N)1×V1-N2×V2)×0.05585×V3}/(V4×V5)；
N1-the molar concentration of a standard solution of potassium permanganate;
V1-consumption of milliliters of potassium permanganate solution;
N2-the molar concentration of ferric ammonium sulfate standard solution used in the titration of trivalent titanium;
V2the number of milliliters of ferric ammonium sulfate standard solution consumed in the titration of an equal quantity of trivalent titanium in the test solution;
V3volumetric flask volume in milliliters;
V4-milliliters of test solution after dilution;
V5-milliliters of solution before dilution;
0.05585-millimolar mass of iron;
sample preparation: the titanium liquid to be cooled and the intermediate product titanium liquid in the examples 1-4 and the comparative examples 1-2 are taken for measurement, the measurement is carried out three times for each example and comparative example, the average value is taken, and the experimental data are shown in the tables 2 and 3.
3. And (3) measuring the iron-titanium ratio in the titanium liquid:
the method comprises the following steps: iron to titanium ratio titanium dioxide content/total iron content
Sample preparation: the titanium dioxide content and the total iron content in the titanium liquid to be cooled and the intermediate product titanium liquid measured in the examples 1 to 4 and the comparative examples 1 to 2 are calculated according to the above calculation formula, each example and comparative example are measured three times, the average value is taken, and the experimental data are shown in the tables 2 and 3.
4. Determination of recovery rate of titanium dioxide in freezing crystallization process
The method comprises the following steps:
(1) quality determination of titanium dioxide in intermediate product titanium liquid
Detecting the content of the titanium dioxide in the intermediate product titanium liquid according to the method for measuring the content of the titanium dioxide in the titanium liquid, and marking the content as C1；
The volume of the intermediate product titanium liquid is marked as V1；
The mass of the titanium dioxide in the intermediate product titanium liquid is recorded as W1, and then W1 ═ C1×V1；
(2) Quality determination of titanium dioxide in titanium liquid to be cooled
Detecting the content of the titanium dioxide in the titanium liquid to be cooled according to the method for measuring the content of the titanium dioxide in the titanium liquid, and marking as C2；
The volume of the titanium liquid to be cooled is marked as V2；
The mass of titanium dioxide in the titanium liquid to be cooled is recorded as W2Then W is2＝C2×V2；
(3) Titanium dioxide recovery (%) > 100 XW1/W2
Sample preparation: the titanium liquid to be cooled and the intermediate product titanium liquid in the examples 1-4 and the comparative examples 1-2 are taken for measurement, the measurement is carried out three times for each example and comparative example, the average value is taken, and the experimental data are shown in the table 3.
5. Ferrous sulfate crystal removing effect on heat exchange coil
The method comprises the following steps: judging according to the table 1;
sample preparation: the removal of ferrous sulfate crystals from the heat exchange coils in examples 1-4 and comparative examples 1-2 was observed and the results are shown in table 3.
TABLE 1 ferrous sulfate crystal removal on coil
| Ferrous sulfate crystal removal effect on coil pipe | Grade |
| Complete removal of | Ⅰ |
| There is ferrous sulfate crystal residue, the residue is no more than 5 | Ⅱ |
| There is ferrous sulfate crystal residue, the residue is more than 5 | Ⅲ |
TABLE 2 analysis table for performance index of titanium liquid to be cooled
| Index (I) | Titanium liquid to be cooled |
| Titanium dioxide content (g/L) | 125.00 |
| Total iron content (g/L) | 125.00 |
| Iron to titanium ratio | 1.0 |
TABLE 3 analysis table of performance indexes of intermediate product titanium liquid in each example and each comparative example
| Index (I) | Example 1 | Example 2 | Example 3 | Example 4 | Comparative example 1 | Comparative example 2 |
| Titanium dioxide content (g/L) | 160.00 | 160.21 | 160.13 | 160.07 | 158.00 | 157.42 |
| Total iron content (g/L) | 53.72 | 53.07 | 53.12 | 53.21 | 53.04 | 53.46 |
| Iron to titanium ratio | 0.33 | 0.33 | 0.33 | 0.33 | 0.34 | 0.34 |
| Recovery ratio of titanium dioxide (%) | 98.46 | 98.59 | 98.54 | 98.50 | 97.23 | 96.87 |
| Ferrous sulfate crystal removal effect on coil pipe | Ⅰ | Ⅰ | Ⅰ | Ⅰ | Ⅰ | Ⅲ |
As can be seen from table 2, compared with the conventional cleaning method, i.e., comparative example 1, the content and recovery rate of titanium dioxide in examples 1 to 4 show obvious advantages, mainly because the method of the present invention is adopted, the titanium dioxide content reduction caused by diluting the titanium liquid to be separated after the washing liquid is directly mixed into the titanium liquid to be separated after the ferrous sulfate crystal on the coil pipe is cleaned by water is avoided, and meanwhile, because the method of the present invention has no cleaning link, the waste liquid after the coil pipe is cleaned in the conventional cleaning method is not lost, i.e., the titanium dioxide in the waste liquid is not lost, the recovery rate of titanium dioxide in the freezing crystallization link of the method of the present invention is improved compared with the conventional cleaning method, and the discharge pressure of the environment-friendly place is also reduced;
compared with the comparative example 2, the examples 1 to 4 and the comparative example 1 show obvious advantages in the removal effect of sulfuric acid topic-pressing crystals on the coil, which is mainly because the bidirectional heating adopted in the invention is adopted, namely the bidirectional heating is respectively carried out inside and outside the coil through titanium liquid at 50 ℃ and hot circulating water at 55-75 ℃, so that ferrous sulfate crystals adhered on the coil can be rapidly dissolved; when 50 ℃ titanium liquid is only introduced into the freezing pot, the dissolution effect is poor and the removal effect of ferrous sulfate crystals is poor due to the fact that the temperature of the titanium liquid is low on one hand and ferrous sulfate crystals on the coil pipe can only be heated in one direction on the other hand;
in conclusion, by adopting the method of the invention, on one hand, ferrous sulfate crystals adhered on the coil can be completely removed, and good heat exchange performance of the coil can be recovered; on the other hand, the content of titanium dioxide in the titanium liquid to be separated and the recovery rate of titanium dioxide in a freezing and crystallizing link are improved, and the subsequent hydrolysis process of the titanium liquid to be separated is facilitated; on the whole, the manpower is saved, the production cost is reduced, the titanium dioxide recovery rate in the freezing crystallization link is improved, the splashing of acid washing liquid in the manual cleaning process is avoided, the corrosion of equipment and components around the freezing pot is greatly reduced, and the accident that the acid washing water splashes to hurt people is eliminated.
While embodiments of the invention have been described above, it is not limited to the applications set forth in the description and the embodiments, which are fully applicable in various fields of endeavor to which the invention pertains, and further modifications may readily be made by those skilled in the art, it being understood that the invention is not limited to the details shown and described herein without departing from the general concept defined by the appended claims and their equivalents.
Claims (10)
1. The ferrous sulfate crystal separation treatment method for titanium dioxide production by a sulfuric acid method is characterized by comprising the following steps:
s1, introducing the titanium liquid to be cooled, introducing a cold circulating liquid into a heat exchange pipeline, crystallizing and separating;
s2, introducing the titanium liquid to be cooled, introducing circulating liquid at 55-75 ℃ into a heat exchange pipeline until ferrous sulfate crystals are dissolved, and then cooling the circulating liquid by the heat exchange pipeline, crystallizing and separating;
the above step S2 is repeated.
2. The method for separating ferrous sulfate crystal from titanium dioxide produced by sulfuric acid process according to claim 1, wherein the temperature of said cold circulation solution is 8-15 ℃.
3. The method for separating ferrous sulfate crystal from titanium dioxide production by sulfuric acid process according to claim 1, wherein said cold circulating liquid is water.
4. The method for separating ferrous sulfate crystals produced by sulfate process titanium dioxide according to claim 3, wherein the cold circulating liquid comprises: water at 20-30 deg.C and water at 8-15 deg.C; specifically, water with the temperature of 20-30 ℃ is introduced into a heat exchange pipeline to cool the titanium liquid to be cooled to 30-40 ℃, and water with the temperature of 8-15 ℃ is introduced into the heat exchange pipeline to continuously cool the titanium liquid to be cooled to 20-25 ℃ so as to separate out ferrous sulfate crystals.
5. The method for separating and crystallizing ferrous sulfate produced by titanium dioxide through a sulfuric acid process according to claim 1, wherein the heat exchange pipeline is a coil pipe.
6. The method for separating ferrous sulfate crystals produced by sulfate process titanium dioxide according to claim 1, wherein the flow rate of the cold circulating liquid is as follows: 4.0-4.8 m/s.
7. The method for separating and treating the ferrous sulfate crystal produced by the titanium white produced by the sulfuric acid method according to claim 1, wherein the flow rate of the circulating liquid at the temperature of 55-75 ℃ is as follows: 5.0-6.0 m/s.
8. The method for separating and crystallizing ferrous sulfate produced by titanium dioxide through a sulfuric acid process as claimed in claim 1, wherein the content of ferrous sulfate in the introduced titanium solution to be cooled is not more than 400 g/L.
9. The method for separating and treating the ferrous sulfate crystal produced by the titanium dioxide sulfate process according to claim 5, wherein the height between each layer of the coil pipe is 80 mm.
10. The method for separating ferrous sulfate crystal from titanium dioxide production by sulfuric acid process of claim 1, wherein said steps S1 and S2 are performed in a freezing pot, said freezing pot comprising:
the top of the pot body is provided with a liquid inlet, and the bottom of the pot body is provided with a liquid outlet;
the coil pipe is arranged in the pot body, one end of the coil pipe extends upwards out of the pot body and is rotatably connected with the pot body, and the other end of the coil pipe is connected with a water outlet pipe and is rotatably and hermetically connected with the water outlet pipe; one end of the coil pipe extending out of the pot body is rotatably and hermetically connected with a water inlet pipe, and the water outlet pipe penetrates through the top of the pot body and extends out of the pot body;
the motor assembly is arranged above the freezing pot and comprises a vertical motor, a first gear coaxially and fixedly connected with an output shaft of the motor and a horizontal second gear meshed with the first gear, and the second gear is coaxially and fixedly connected with one end of the coil pipe, which is positioned outside the pot body;
the scraping component is arranged in the pot body and comprises a vertical scraping plate and a pair of supporting rods which are respectively arranged at the upper side and the lower side of the scraping plate; the scraper is positioned outside the coil and close to the outer wall of the coil, and the height of the scraper is greater than that of the coil; one end of each supporting rod penetrates through the pot body and is rotatably connected with the pot body, the other end of each supporting rod is rotatably connected with a vertical supporting plate, the top of each vertical supporting plate is fixedly connected with the inner wall of the top of the pot body, threads are arranged on the outer wall of each supporting rod, sliders are coaxially screwed on the threads, and one surfaces, opposite to the sliders, are fixedly connected with corresponding end portions of the scrapers.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101550129A (en) * | 2009-03-06 | 2009-10-07 | 天津金牛电源材料有限责任公司 | Method for refining 1,3-propane sultone |
| CN201543266U (en) * | 2009-09-30 | 2010-08-11 | 安徽丰原化工装备有限公司 | Double-cold crystallizer |
| CN206444230U (en) * | 2016-12-29 | 2017-08-29 | 广州金科水务工程有限公司 | A kind of big flow forced circulation good antiscale property freezing and crystallizing device |
| CN206731091U (en) * | 2017-04-17 | 2017-12-12 | 常州都铂高分子有限公司 | A kind of coiled reactor of convenient cleaning |
-
2020
- 2020-11-20 CN CN202011310719.7A patent/CN112337132A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101550129A (en) * | 2009-03-06 | 2009-10-07 | 天津金牛电源材料有限责任公司 | Method for refining 1,3-propane sultone |
| CN201543266U (en) * | 2009-09-30 | 2010-08-11 | 安徽丰原化工装备有限公司 | Double-cold crystallizer |
| CN206444230U (en) * | 2016-12-29 | 2017-08-29 | 广州金科水务工程有限公司 | A kind of big flow forced circulation good antiscale property freezing and crystallizing device |
| CN206731091U (en) * | 2017-04-17 | 2017-12-12 | 常州都铂高分子有限公司 | A kind of coiled reactor of convenient cleaning |
Non-Patent Citations (2)
| Title |
|---|
| 唐振宁编: "《钛白粉的生产与环境治理》", 31 May 2000, 北京：化学工业出版社 * |
| 黄继红主编: "《抗性淀粉生产技术及其应用》", 31 January 2017, 郑州：河南科学技术出版社 * |
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