CN-117899742-B - Method and system for efficiently granulating and modifying titanium-rich material fine powder

CN117899742BCN 117899742 BCN117899742 BCN 117899742BCN-117899742-B

Abstract

A method and system for high-efficiency granulating and modifying of Ti-enriched fine powder includes granulating subsystem with high-speed shearing granulator, drying subsystem with drying fluidized bed, cyclone dust collector and cloth bag dust collector, solidifying subsystem with cyclone preheater, fume combustion chamber, solidifying bed, combustion heating chamber and cooler. The method comprises the steps of delivering titanium-rich materials, high titanium slag fine powder, binding agent and water into a high-speed shearing granulator for granulation, delivering to a drying fluidized bed for drying treatment, delivering to a multi-stage cyclone preheater, performing heat exchange with the flue gas after combustion deoxidation to realize preheating, delivering to a consolidation bed, and consolidating to obtain the product. The method has the advantages that the system structure is simple, the applicability is strong, the granulating modification method relies on the pyrolysis of Ti/Fe organic binders in the preheating process to obtain the low-valence oxide, the low-valence oxide in the high titanium slag is rapidly oxidized and released in the consolidation process to cause local overheating and liquid phase sintering, the high-efficiency consolidation is realized, and the modified particles with excellent performance are obtained.

Inventors

FAN CHUANLIN
LI XIN
LI HONGZHONG
TANG JIANGUO
YU XUECHENG
ZHU QINGSHAN
JU YELIANG
MA SUGANG
ZHAO BAOKUN
PAN FENG
ZHAO QINGYU
GE YU

Assignees

中信钛业股份有限公司
中国科学院过程工程研究所
中国中信集团有限公司

Dates

Publication Date: 20260508
Application Date: 20231229

Claims (10)

1. The high-efficiency granulating and modifying system for the titanium-rich material fine powder comprises a titanium-rich material bin, a high-titanium slag fine powder bin and a binder bin, wherein an organic titanium/iron binder or a mixture of the organic titanium/iron binder and the organic binder is arranged in the binder bin, the organic binder is one or two of dextrin and carboxymethyl cellulose, and the organic titanium/iron binder is at least one of titanium oxalate, ferrous oxalate, metatitanic acid, ferric alginate and ferrous alginate; The device is characterized in that the granulating device is a high-speed shearing granulator, the drying device is a drying fluidized bed, an air outlet of the drying device is connected with a cyclone dust collector, a dust collection bin is connected to the air outlet of the cyclone dust collector, an air outlet of the cyclone dust collector is communicated with a bag dust collector, an induced draft fan is connected to the air outlet of the induced draft fan, a blow-down pipe is connected to the air outlet of the induced draft fan, the air outlet of the bag dust collector is communicated with the air inlet of the dust collection bin, an air inlet of the drying device is communicated with an air outlet of a cyclone preheater, an air inlet of the cyclone preheater is communicated with an air outlet of the drying device and an air outlet of a flue gas combustion chamber, the air inlet of the flue gas combustion chamber is respectively communicated with an air outlet of a consolidation bed and a flue gas channel, the air outlet of the consolidation bed is connected with a material inlet of a cooler, the air inlet of the bed is connected with a combustion heating chamber, the air inlet of the combustion chamber is connected with a fuel pipe, the air inlet of the fuel pipe is connected with the air inlet of the cooler, and the air outlet of the fuel pipe is connected with the air inlet of the cooler.
2. The efficient granulating and modifying system for titanium-rich fine powder of claim 1, wherein the dust collection bin discharge port is communicated with the feed port of the high-speed shearing granulator.
3. The efficient granulating and modifying system for titanium-rich fine powder of claim 1, wherein the water inlet of the high-speed shearing granulator is connected with a process water pipeline.
4. The efficient granulating and modifying system for titanium-rich fine powder of claim 1, wherein the cyclone preheater is multi-stage, the lower discharge port of the higher cyclone is connected with the feed port of the lower cyclone, and the top gas outlet of the lower cyclone is connected with the gas inlet of the higher cyclone.
5. A high-efficiency granulating and modifying method for titanium-rich material fine powder by using the system disclosed in claim 1 is characterized by comprising the following steps of (1) feeding titanium-rich material, high titanium slag fine powder and a binder into a high-speed shearing granulator, adding water, and obtaining granules with the particle size of 0.15-2 mm under the action of the high-speed shearing granulator, wherein the rotating speed of a rotor of the granulator is 100-3000 rpm, the rotating speed of a disc is 10-200 rpm, the granulating time is 5-60 min, the binder is an organic titanium/iron binder or a mixture of the organic titanium/iron binder and the organic binder, the organic binder is one or two of dextrin and carboxymethyl cellulose, the organic titanium/iron binder is at least one of titanium oxalate, ferrous oxalate, metatitanic acid, ferric alginate and ferrous alginate, and the mass ratio of the titanium-rich material fine powder, the high titanium slag fine powder, the binder and the water is 1:0.1-0.3:0.005-0.05:0.05-0.1; (2) Sending the granulating material into a drying fluidized bed, and introducing the flue gas of the multi-stage cyclone preheater into the drying fluidized bed to dry the granulating material; (3) The method comprises the steps of drying granulated materials, feeding the dried granulated materials into a multi-stage cyclone preheater, feeding the smoke generated by a drying fluidized bed into a cyclone separator and a bag dust collector, discharging the smoke subjected to dust removal through a draught fan, feeding the obtained dust into a dust collection bin, returning the dust to a high-speed shearing granulator, drying the granulated materials, feeding the dried granulated materials into the multi-stage cyclone preheater, exchanging heat with the smoke generated by a smoke combustion chamber to preheat the granulated materials, feeding fuel into the smoke combustion chamber, feeding hot smoke of a consolidation bed to enable the fuel to burn and consume oxygen in the hot smoke, feeding the preheated granulated materials into the consolidation bed, consolidating the granulated materials in the consolidation bed by means of high-temperature smoke generated by burning in a burning heating chamber, feeding the cooled granulated materials into a cooler, feeding the cooled mixed gas of air and nitrogen into the cooler, exchanging heat with the high-temperature consolidated materials to heat the obtained mixed gas, feeding the heated mixed gas into a burning heating chamber, burning the fuel in the burning heating chamber to generate high-temperature smoke, feeding the consolidation bed, and cooling the high-temperature smoke into the consolidation bed to obtain the consolidated materials.
6. The efficient granulating and modifying method for the titanium-rich material fine powder according to claim 5 is characterized in that the titanium-rich material TiO2 content is 70% -98%, the average particle size is 5% -100 μm, the CaO content is 0% -0.5%, the MgO content is 0% -1.5%, the Gao Tai slag TiO 2 content is 70% -95%, the average particle size is 5% -100 μm, the CaO content is 0% -0.5%, and the MgO content is 0% -1.5%.
7. The efficient granulation modification method of the titanium-rich material fine powder according to claim 5, wherein the temperature in the drying fluidized bed is 80-200 ℃, the gas apparent velocity is 0.5-2.0 m/s, and the average residence time of particles is 5-60 min.
8. The efficient granulating and modifying method of the titanium-rich material fine powder according to claim 5, wherein the multi-stage cyclone preheater has a stage number of 2-6, and the oxygen content of the preheated high-temperature gas subjected to combustion deoxidation is 0% -5%.
9. The efficient granulating and modifying method of the titanium-rich material fine powder according to claim 5, wherein the solidifying bed is a bubbling fluidized bed or a circulating fluidized bed, the temperature in the solidifying bed is 800-1100 ℃, and the average residence time of particles is 15-60 min.
10. The efficient granulating and modifying method for titanium-rich material fine powder according to claim 5, wherein the cooler adopts a bubbling fluidized bed, the apparent gas velocity is 0.5-2.0 m/s, the average particle residence time is 30-120 min, and the volume flow ratio of nitrogen gas to air of the mixed gas of air and nitrogen gas is (0-1): 1.

Description

Method and system for efficiently granulating and modifying titanium-rich material fine powder Technical Field The invention relates to a method and a system for efficiently granulating and modifying titanium-rich material fine powder. Background Titanium tetrachloride is an intermediate product in the production process of titanium and its compounds, and is an important raw material for the development of titanium industry. Titanium tetrachloride can be used for oxidizing to produce titanium dioxide, or magnesium can be used for reducing to produce titanium sponge, and then titanium, titanium alloy and the like are produced. With the rapid development of the titanium industry in recent years, the demand for titanium raw materials has been expanding. At present, the utilization paths of titanium resources mainly comprise two kinds of technologies, namely a chlorination process and a sulfuric acid process, and the chlorination process comprises fluidization chlorination and molten salt chlorination. The fluidization chlorination process has short flow, low cost, little pollution and large productivity, and is a mainstream advanced titanium resource utilization technology. The fluidized chlorination process is to carry out carbon chlorination on the titanium-containing raw material in a fluidized bed to obtain titanium tetrachloride, wherein the standard of the titanium tetrachloride on the raw material is very high, the grade of titanium dioxide is generally more than 90%, and the particle size is 75-300 mu m and the proportion is more than 90%. Therefore, in the conventional fluidization chlorination process, in order to control the particle size of the raw material, a large amount of fine powder titanium-rich material is generated and cannot be utilized, so that the raw material utilization rate is low, and part of fine-particle-grade titanium-rich material cannot be recovered. The problem that the fine-fraction titanium-rich raw material cannot be utilized is mainly solved around two modes of optimizing a chlorination furnace reactor and raw material granulation treatment at present. CN111908501a discloses a "chlorination furnace for fine-grade titanium-rich material and its boiling chlorination process", the chlorination furnace is provided with a plurality of chlorination units, each unit is provided with an independent air inlet pipe and control system, and the upper portion of each reactor is provided with an expansion section. CN103818951 a discloses a "fluidized bed chlorination furnace adapted to fine-fraction titanium-rich material" which is also provided with an expansion section at the upper part of the chlorination furnace, and the reduction of the gas velocity enables the fine-fraction material to return to the main body of the chlorination furnace, and in addition, chlorine gas enters tangentially, which is favorable for realizing gas-solid separation, thereby reducing the escape of fine-fraction material. In both methods, the structure of the chlorination furnace reactor is optimized, the top of the reactor is mainly provided with an expansion section, in theory, the top of the chlorination furnace is provided with an expansion section, the gas velocity of the part can be reduced, part of fine-fraction titanium-rich raw materials can fall back to the main body of the chlorination furnace, however, the part of the titanium-rich raw materials have too fine particle size, and the reaction area of the chlorination furnace has higher gas velocity due to titanium tetrachloride generated by the reaction in the concentrated phase area of the chlorination reaction. Therefore, even if the enlarged section is present, it is difficult for the fine fraction titanium-rich raw material to return to the dense phase zone, and chlorination reaction is difficult to occur. Therefore, more researches start from the source and carry out granulation treatment on raw materials so as to radically solve the problem of fine powder utilization. For example, US2761760 discloses a process for producing titanium tetrachloride which uses a titanium-rich material of less than 100 mesh in combination with fine carbon powder and a binder to pelletize, uses highly reactive NOCl as a chlorinating agent, and uses a fixed bed reactor to reduce the chlorination temperature to 400 ℃. However, the NOCl used in this process is expensive, the cyclic regeneration cost is high, and the fixed bed reaction efficiency is low, which is difficult to apply on a large scale in production. US4187117 discloses titanium slag-coke pre-agglomerating particles for fluid bed chlorination, wherein the particle size of titanium slag and asphalt is controlled below 325 meshes, a binder is added, a disc granulator is used for granulation, the granularity of pelletizing is controlled between 28 meshes and 100 meshes, thermosetting is carried out at 900-1000 ℃, and ferrous chloride, sodium sulfite, sodium sulfate or nylon is used as the binder. CN106319246