Method for cleaning titanium sponge oil
By employing multi-stage countercurrent cleaning and distillation recovery methods, and using alkane or halogenated hydrocarbon solvents with ultrasonic-assisted cleaning, the problem of incomplete oil contamination in sponge titanium was solved, achieving efficient cleaning and resource recycling, while reducing energy consumption and costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- YUNNAN GUOTAI TITANIUM METAL CO LTD
- Filing Date
- 2026-02-27
- Publication Date
- 2026-06-05
AI Technical Summary
In existing technologies, sponge titanium oil pollution cleaning is incomplete, resulting in secondary pollution, high energy consumption, and significant cleaning costs and environmental pressures, making it difficult to meet the requirements of downstream titanium material production.
A multi-stage countercurrent cleaning method is adopted, using alkane or halogenated hydrocarbon solvents and ultrasonic-assisted cleaning, combined with mechanical stirring. After cleaning, the cleaning agent is recovered by distillation and the waste oil is utilized as a resource. A programmable logic controller is used for system integration and control.
It achieves efficient and thorough cleaning of oil stains on sponge titanium, with a cleaning efficiency of over 99%, reducing energy consumption and production costs. It also realizes closed-loop circulation of cleaning agents and efficient utilization of resources, which is in line with the concept of green manufacturing.
Smart Images
Figure CN122147345A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of post-processing technology in the production of titanium sponge, specifically a method for cleaning titanium sponge oil. Background Technology
[0002] Titanium sponge is a fundamental raw material in the titanium industry, and its purity directly determines the processing performance and product quality of downstream titanium materials. In the industrial production process of titanium sponge, the massive titanium sponge agglomerates must undergo mechanical rolling, crushing, and other processes to be processed into particle sizes that meet production requirements. During this process, the hydraulic or lubrication systems of the rolling and crushing equipment are at risk of leakage due to seal failure or pipeline rupture. Leaked mineral oil can adhere to the surface of the titanium sponge and penetrate its porous structure, causing oil contamination.
[0003] Mineral oil-contaminated sponge titanium loses its market value and can only be disposed of as waste, causing huge economic losses to enterprises. Downstream titanium smelting and processing enterprises have extremely high requirements for the purity of sponge titanium. The oil in contaminated sponge titanium will decompose and produce hydrocarbon gases during the high-temperature smelting process. These gases will form pores inside the titanium material and trigger a carbonization reaction, which will seriously damage the mechanical properties and metallurgical quality of the titanium material, making it unable to meet the usage standards of downstream production.
[0004] Currently, the industry primarily uses water-based cleaning agents or surfactants to clean oil-contaminated sponge titanium. However, these methods have several intractable drawbacks. Firstly, cleaning is incomplete; water-based cleaning agents have limited penetration capabilities and cannot reach the porous structure of the sponge titanium to dissolve oil, easily leaving residues. Secondly, secondary pollution occurs; the cleaning process generates large amounts of oily wastewater, requiring companies to construct complex wastewater treatment systems, significantly increasing environmental protection investment and production costs. Thirdly, energy consumption is high; residual moisture on the surface and within the pores of the sponge titanium after cleaning must be removed by high-temperature drying in a vacuum oven, consuming significant energy and prolonging the processing cycle. Fourthly, potential quality risks exist; the water washing process may cause localized oxidation of the sponge titanium, introducing other impurities and further reducing the product quality.
[0005] Therefore, developing a highly efficient, thorough, low-energy-consumption, and resource-recoverable method for cleaning oil-contaminated sponge titanium has become an urgent need in the titanium industry. Summary of the Invention
[0006] The purpose of this invention is to provide a cleaning method for sponge titanium oil, so as to solve the problems mentioned in the background art, such as incomplete cleaning, secondary pollution, and high energy consumption of traditional sponge titanium using water-based cleaning methods.
[0007] To achieve the above objectives, the present invention provides the following technical solution:
[0008] A cleaning method for sponge titanium oil, employing a cleaning and recovery system including a cleaning tank, a cleaning agent storage tank, No. 1 to No. 5 liquid collection tanks, a distillation kettle, a condenser, a condensate recovery tank, a concentrated waste oil tank, a ventilation drying oven, and pipelines and control systems connecting each piece of equipment, characterized by the following steps:
[0009] S1 Multi-stage Countercurrent Cleaning: Oil-impregnated titanium sponge is loaded into the cleaning tank. Cleaning agent is injected in stages from the cleaning agent storage tank for at least two cleaning cycles. Each cleaning solution is discharged into the corresponding numbered collection tank. The cleaning agent dosage satisfies the formula... ,in The mass ratio coefficient of the cleaning agent to the titanium sponge is 5-10 L / kg. For the mass of oil-containing sponge titanium, Let be the cross-sectional area of the cleaning tank. The cleaning agent level is 10-20cm above the surface of the titanium sponge pile.
[0010] S2 Evaporation Drying: The cleaned sponge titanium is transferred to a ventilated drying oven and dried by natural evaporation. The drying endpoint meets the residual amount formula. ,in This refers to the residual cleaning agent content on the surface of the titanium sponge, expressed in mg / kg. For the quality of residual cleaning agent, The mass of the dried sponge titanium;
[0011] S3 Solvent Recovery: The high-oil-concentration cleaning solution from collection tanks #1 to #3 is pumped into a distillation kettle, heated and distilled, and then condensed to obtain pure cleaning agent. The cleaning agent recovery rate satisfies the formula:
[0012] ;
[0013] in The single distillation recovery rate of the cleaning agent. To recover the volume of cleaning agent, The volume of cleaning agent in the cleaning solution before distillation is the volume of the cleaning agent. The recovered cleaning agent is returned to the cleaning agent storage tank for recycling, and the distillation residue is discharged into the concentrated waste oil tank.
[0014] S4 waste oil reuse: The concentrated waste oil in the concentrated waste oil tank is transported to the titanium tetrachloride production process and mixed into the vanadium removal oil used for crude titanium tetrachloride vanadium removal.
[0015] Preferably, the cleaning process in step S1 is performed five times. The first cleaning solution is discharged into tank #1, the second into tank #2, the third into tank #3, the fourth into tank #4, and the fifth into tank #5. The clarity and transparency of the cleaning solution in tank #5 is used as the criterion for determining whether the sponge titanium is cleaned properly.
[0016] Preferably, the cleaning agent is selected from one or a mixture of several alkane solvents and halogenated hydrocarbon solvents; the alkane solvent is an isoalkane solvent oil with a carbon chain length of C8-C10 and a boiling point range of 80-120℃; the halogenated hydrocarbon solvent is trichloroethylene with a purity of ≥99.5% and a boiling point of 86-88℃; the boiling point of the cleaning agent is 50-200℃ lower than the boiling point of the mineral oil to be removed.
[0017] Preferably, ultrasonic-assisted cleaning is applied during the cleaning process in step S1, with an ultrasonic frequency of 20kHz to 40kHz; the cleaning temperature is 25℃ at room temperature or heated to 60-80% of the boiling point of the cleaning agent, corresponding to a temperature range of 40-60℃; the cleaning time is set in gradients, with the first cleaning time being 30-40min and the second to fifth cleaning times being 20-30min.
[0018] Preferably, the cleaning agent must simultaneously meet the following characteristics: complete miscibility with mineral oil, no chemical reaction with sponge titanium, and moderate saturated vapor pressure at room temperature. The miscibility criterion for the cleaning agent and mineral oil is that no stratification occurs after standing for 12 hours after mixing, and the difference in boiling points between the cleaning agent and mineral oil satisfies the formula... ,in The boiling point of the mineral oil to be removed, The boiling point of the cleaning agent. The value range is 50-200℃; the carbon chain distribution uniformity of the alkane solvent is ≥90%, and the impurity content of the halogenated hydrocarbon solvent is ≤0.5%; the purity of the cleaning agent is detected by gas chromatography, and the detection conditions are capillary column temperature 80-120℃, carrier gas is nitrogen, and flow rate is 1mL / min.
[0019] Preferably, the cleaning process in step S1 is accompanied by a stirring operation at a speed of 30-60 r / min. The stirring paddle has an anchor-type structure, and the distance between the paddle blade and the inner wall of the cleaning tank is 5-10 cm. The cleaning agent level is monitored in real time by a level sensor to ensure that it is always 10-20 cm above the surface of the sponge titanium pile, preventing the sponge titanium from being exposed and causing cleaning dead zones. The oil removal rate of the cleaning effect satisfies the formula:
[0020] ;
[0021] in, To determine the quality of the oil stains adhering to the surface of the sponge titanium before cleaning, The quality of residual oil on the surface of the sponge titanium after cleaning is determined. When the oil content on the surface of the sponge titanium is >5%, the first cleaning time is extended to 40-45 minutes, and the ultrasonic power is increased to 120% of the rated power.
[0022] Preferably, the evaporation drying conditions in step S2 are as follows: the ventilated drying chamber has an internal airflow distribution plate to ensure uniform airflow across the sponge titanium surface; the temperature inside the chamber is controlled by a PID temperature control system with a temperature fluctuation range of ≤±2℃; the ventilation rate is 1-3m / s; and the drying time is 8-24h. The residual amount of cleaning agent on the sponge titanium surface is detected by pyrolysis-gas chromatography. The detection steps are as follows: 10g of sponge titanium sample is placed in a pyrolysis furnace and pyrolyzed at 300℃ for 30min; the pyrolysis gas is separated and detected by a gas chromatograph. The drying uniformity is judged by the difference in residual amount of cleaning agent in different parts of the sponge titanium being ≤2mg / kg. During the drying process, the exhaust gas from the ventilated drying chamber is treated by activated carbon adsorption before being discharged; the adsorbent can be recycled and regenerated after saturation.
[0023] Preferably, the distillation conditions in step S3 are as follows: the heating method is selected according to the processing scale; electric heating is used for small-scale processing, and steam heating is used for large-scale processing; the distillation temperature is ±5℃ of the boiling point of the cleaning agent; the distillation system pressure is at atmospheric pressure or under reduced pressure, with a reduced pressure value of 0.05-0.08MPa; during the distillation process, an explosion-proof temperature sensor is used to monitor the temperature inside the vessel in real time, and the over-temperature alarm threshold is set to the boiling point of the cleaning agent +10℃; the cleaning agent recovery rate is ≥95%, and the purity is ≥99%; the purity is detected by gas chromatography, and the purity is calculated using the area normalization method; the distillation efficiency satisfies the formula... ,in This refers to the volume of cleaning agent recovered per unit time. Where is the feed volume of the distillation vessel. The distillation time is specified; the concentrated waste oil after distillation has a water content of ≤0.1%, which meets the raw material requirements for the titanium tetrachloride vanadium removal process.
[0024] Preferably, in the five-stage cleaning process of step S1, the cleaning agent is injected using a combination of recycled cleaning agent and fresh cleaning agent. For the first to third cleanings, low-oil-content recycled cleaning agent from the No. 4 and No. 5 collection tanks is used first, while for the fourth and fifth cleanings, fresh cleaning agent from the cleaning agent storage tank is injected. The cleaning time gradient is dynamically adjusted according to the oil concentration. When the oil concentration is 1%-3%, the first cleaning time is 30 minutes, and the second to fifth cleaning times are 20 minutes. When the oil concentration is 3%-5%, the first cleaning time is 35 minutes, and the second to fifth cleaning times are 25 minutes. Ultrasonic cleaning and mechanical stirring work together. When the ultrasonic frequency is 20kHz, the stirring speed is matched with 30r / min. When the ultrasonic frequency is 40kHz, the stirring speed is matched with 60r / min to enhance the penetration effect of the cleaning agent in the porous structure of the titanium sponge.
[0025] Preferably, the pipeline and control system employs a programmable logic controller (PLC) for centralized control. The PLC integrates a parameter acquisition module, a logic operation module, and an execution control module. The parameter acquisition module collects real-time data on the temperature and liquid level of the cleaning tank, the temperature and pressure of the distillation kettle, and the temperature and ventilation rate of the ventilation drying chamber. The logic operation module executes data according to a preset algorithm. Automatically adjust cleaning parameters, among which To determine the overall cleaning effect, For cleaning temperature, This refers to the cleaning agent level. The system is designed for cleaning time; the execution control module enables directional delivery of the cleaning agent between the cleaning tank, cleaning agent storage tank, liquid collection tank, and distillation kettle, and the flow rate of the cleaning agent is precisely controlled by an electromagnetic flow meter with a flow error of ≤±2%; the system has a fault alarm function, automatically stopping liquid feeding when the liquid level in the liquid collection tank reaches 80% of the upper limit, and automatically depressurizing when the pressure in the distillation kettle exceeds 0.08MPa; at the same time, the system is equipped with a data storage module, which can record the process parameters and test results of each cleaning, realizing product quality traceability.
[0026] Compared with the prior art, the beneficial effects of the present invention are:
[0027] (1) The cleaning method for oily sponge titanium of the present invention has high cleaning efficiency and thorough cleaning effect, and can effectively restore the product value of oil-contaminated sponge titanium. The present invention selects alkane or halogenated hydrocarbon organic solvents that are completely miscible with mineral oil as cleaning agents. These cleaning agents can quickly penetrate into the porous structure of sponge titanium and fully dissolve the oil stains in the pores. Combined with a multi-stage countercurrent cleaning process, plus the synergistic effect of ultrasonic assistance and mechanical stirring, the oil stain removal efficiency can be significantly improved, and the oil stain removal rate can be achieved at over 99%. The residual amount of cleaning agent on the surface of the cleaned sponge titanium is ≤10mg / kg, and the carbon content can be reduced to 0.022%-0.028%, reaching the second-grade product standard. This successfully transforms the originally wasteful contaminated sponge titanium into a qualified product that meets the requirements of downstream use, greatly reducing the economic losses of enterprises.
[0028] (2) The cleaning method for sponge titanium oil in this invention is free from secondary pollution throughout the entire process, realizing a closed-loop cycle of the cleaning system and efficient utilization of resources. The entire cleaning and recycling process does not require the use of water, eliminating the generation of oily wastewater at the source and avoiding the cost and environmental pressure of subsequent wastewater treatment. The oily cleaning solution achieves efficient recovery of the cleaning agent through a distillation process, with a single recovery rate of ≥95% and a purity of ≥99% after recovery. It can be directly returned to the cleaning system for recycling, significantly reducing the consumption cost of the cleaning agent. The concentrated waste oil generated after distillation can also be transported to the titanium tetrachloride production process as a raw material for vanadium removal oil for resource utilization. This not only solves the problem of hazardous waste disposal but also saves raw material expenses for the upstream production process, fully conforming to the development concept of green manufacturing.
[0029] (3) The cleaning method for oily sponge titanium of the present invention significantly reduces energy consumption and overall production costs, and has strong feasibility for industrial application. After cleaning, the sponge titanium can be dried in a ventilated drying oven by means of the natural volatility of the cleaning agent, eliminating the high-temperature drying step required by the traditional water washing method. The drying energy consumption is reduced by about 70% compared with the traditional method. At the same time, the system adopts a programmable logic controller for centralized control, which can collect and automatically adjust key process parameters such as temperature, liquid level, and pressure in real time, which not only ensures the stability and consistency of the cleaning effect, but also realizes full traceability of product quality. In addition, low-oil-content recycled cleaning agent is used preferentially in the multi-stage cleaning process, which further reduces the amount of fresh cleaning agent used. According to calculations, the comprehensive cleaning cost of the present invention is only 560-600 yuan / ton of oily sponge titanium, which creates higher economic benefits for enterprises while improving product quality. Attached Figure Description
[0030] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are explained in detail together with the embodiments of the invention, but do not constitute a limitation thereof.
[0031] Figure 1 This is a flowchart illustrating the core architecture of the cleaning method for sponge titanium oil according to the present invention. Detailed Implementation
[0032] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.
[0033] like Figure 1As shown, the cleaning method for sponge titanium oil of the present invention employs a system including a cleaning tank 2, a cleaning agent storage tank 3, 1# to 5# liquid collection tanks 8 to 12, a distillation kettle 13, a condenser 6, a condensate recovery tank 7, a concentrated waste oil tank 14, a ventilation drying box 4, and pipelines and control systems connecting the various devices. The pipelines and control systems are centrally controlled by a programmable logic controller (PLC). The PLC integrates a parameter acquisition module, a logic operation module, and an execution control module, enabling coordinated operation of the various devices, precise parameter control, fault alarms, and data traceability. The present invention will be described in detail below:
[0034] The method for cleaning sponge titanium oil according to the present invention specifically includes the following steps:
[0035] S1 Multi-stage Countercurrent Cleaning: First, evenly load the oil-containing sponge titanium into the cleaning tank 2, ensuring the sponge titanium is piled up flat and avoiding dead corners. Open the discharge valve of the cleaning agent storage tank 3. Calculate the required amount of cleaning agent according to the mass of the oil-containing sponge titanium and the cross-sectional area of the cleaning tank 2, using the formula V=k×m+S×h. Here, k is the mass ratio coefficient of cleaning agent to sponge titanium, taken as 5-10L / kg, m is the mass of the oil-containing sponge titanium, S is the cross-sectional area of the cleaning tank 2, and h is the height of the cleaning agent above the sponge titanium pile, taken as 10-20cm. Inject the cleaning agent into the cleaning tank 2 in stages for five-stage countercurrent cleaning, ensuring that the sponge titanium is completely submerged in the cleaning agent each time.
[0036] The cleaning agent is selected from one or more of alkane solvents and halogenated hydrocarbon solvents. It must simultaneously meet the following characteristics: complete miscibility with mineral oil, no chemical reaction with sponge titanium, and moderate saturated vapor pressure at room temperature. The miscibility criterion for the cleaning agent and mineral oil is that no stratification occurs after standing for 12 hours after mixing. The boiling point difference between the cleaning agent and mineral oil satisfies the formula ΔT = T. m -T s T m To determine the boiling point of the mineral oil to be removed, T s The boiling point of the cleaning agent is ΔT, which ranges from 50 to 200℃. The alkane solvent is an isoalkane solvent oil with a carbon chain length of C8-C10, a boiling point range of 80-120℃, and a carbon chain distribution uniformity of ≥90%. The halogenated hydrocarbon solvent is trichloroethylene with a purity of ≥99.5%, a boiling point of 86-88℃, and an impurity content of ≤0.5%. The purity of the cleaning agent is determined by gas chromatography under the following conditions: capillary column temperature of 80-120℃, carrier gas of nitrogen, and flow rate of 1 mL / min.
[0037] During the cleaning process, ultrasonic-assisted cleaning and mechanical stirring are applied simultaneously. The ultrasonic frequency is 20kHz to 40kHz, and the cleaning temperature is 25℃ or heated to 60-80% of the boiling point of the cleaning agent, corresponding to a temperature range of 40-60℃. The stirring speed is 30-60r / min, and the stirring paddle has an anchor structure with a distance of 5-10cm between the paddle blade and the inner wall of the cleaning tank 2. The ultrasonic cleaning and mechanical stirring work together, with a stirring speed of 30r / min matched when the ultrasonic frequency is 20kHz and a stirring speed of 60r / min matched when the ultrasonic frequency is 40kHz, to enhance the penetration effect of the cleaning agent in the porous structure of the titanium sponge.
[0038] The cleaning time is set in gradients and dynamically adjusted according to the oil concentration on the titanium sponge surface. When the oil concentration is 1%-3%, the first cleaning time is 30 minutes, and the second to fifth cleanings are 20 minutes each. When the oil concentration is 3%-5%, the first cleaning time is 35 minutes, and the second to fifth cleanings are 25 minutes each. When the oil content on the titanium sponge surface is >5%, the first cleaning time is extended to 40-45 minutes, and the ultrasonic power is increased to 120% of the rated power. The oil removal rate of the cleaning effect satisfies the formula η. o =(m o1 -m o2 ) / m o1 ×100%≥99%, where m o1 To determine the quality of oil stains adhering to the surface of the titanium sponge before cleaning, m o2 The quality of residual oil stains on the surface of the sponge titanium after cleaning.
[0039] After each cleaning cycle, the cleaning solution is discharged into the corresponding numbered collection tanks. The first cleaning solution is discharged into collection tank #1 (8), the second into collection tank #2 (9), the third into collection tank #3 (10), the fourth into collection tank #4 (11), and the fifth into collection tank #5 (12). The cleaning agent is injected using a combination of recycled and fresh cleaning agent. For the first to third cleaning cycles, the low-oil-content recycled cleaning agent in collection tanks #4 and #5 (11 and #12) is used first. For the fourth to fifth cleaning cycles, fresh cleaning agent is injected from the cleaning agent storage tank 3. The clarity and transparency of the cleaning solution in collection tank #5 (12) is used as the criterion for determining whether the sponge titanium cleaning is qualified. The cleaning agent level in cleaning tank 2 is monitored in real time by a level sensor to ensure that it is always 10-20cm above the sponge titanium stack surface to prevent the sponge titanium from being exposed and causing cleaning dead zones. Collection tanks #1 to #5 (8 to #12) are all equipped with level monitoring modules to prevent cleaning solution overflow.
[0040] S2 Evaporation Drying: Remove the cleaned titanium sponge from the cleaning tank 2 and spread it evenly on the tray inside the ventilated drying chamber 4. The thickness of the spread should be controlled at 5-10cm to avoid excessive accumulation that would affect the uniformity of drying. The ventilated drying chamber 4 has an internal airflow distribution plate to ensure that the airflow evenly sweeps the surface of the titanium sponge. The temperature inside the chamber is controlled by a PID temperature control system with a temperature fluctuation range of ≤±2℃. The ventilation rate is 1-3m / s, and the drying time is 8-24h.
[0041] During the drying process, the exhaust gas from the ventilated drying chamber 4 is treated by activated carbon adsorption before being discharged. The adsorbent can be recovered and regenerated after saturation. The drying endpoint satisfies the residual amount formula R=m r / m t ×10 6 ≤10, where R is the residual amount of cleaning agent on the surface of the titanium sponge, in mg / kg, m r For residual cleaning agent quality, m t The quality of the dried sponge titanium was determined. The residual amount of cleaning agent on the surface of the sponge titanium was detected by pyrolysis-gas chromatography. The detection steps were as follows: 10g of sponge titanium sample was placed in a pyrolysis furnace and pyrolyzed at 300℃ for 30min. The pyrolysis gas was separated and detected by gas chromatography. The criterion for determining the uniformity of drying was that the difference in residual amount of cleaning agent in different parts of the sponge titanium was ≤2mg / kg.
[0042] S3 Solvent Recovery: After the multi-stage countercurrent cleaning is completed, the high oil concentration cleaning solution in the No. 1 collection tank 8 and No. 2 collection tank 9 is pumped into the distillation kettle 13 first. Then, the cleaning solution in the No. 3 collection tank 10 is processed in sequence according to the oil concentration. The low oil concentration cleaning solution in the No. 4 collection tank 11 and No. 5 collection tank 12 is directly returned to the cleaning agent storage tank 3 for recycling.
[0043] Distillation conditions are selected based on the processing scale: electric heating is used for small-scale processing, while steam heating is used for large-scale processing. The distillation temperature is ±5℃ of the cleaning agent's boiling point. The distillation system pressure is either atmospheric or reduced pressure, with the reduced pressure value being 0.05-0.08 MPa. An explosion-proof temperature sensor is used to monitor the temperature inside the vessel in real time during distillation, and an over-temperature alarm threshold is set at the cleaning agent's boiling point +10℃. The distillation efficiency satisfies the formula η. d =V d / (V f ×t), where V d V is the volume of cleaning agent recovered per unit time. f t represents the feed volume of the distillation vessel 13, and t represents the distillation time.
[0044] The cleaning agent vapor produced by distillation is condensed by condenser 6 and then flows into condensation recovery tank 7 for settling and clarification to obtain pure cleaning agent. The cleaning agent recovery rate satisfies the formula η=V r / V0×100%≥95%, where η is the single distillation recovery rate of the cleaning agent, Vr The volume of the cleaning agent to be recovered is V0, which is the volume of the cleaning agent in the cleaning solution before distillation. The recovered cleaning agent is tested by gas chromatography and its purity is ≥99%. The purity is calculated by the area normalization method. After passing the test, it is returned to the cleaning agent storage tank 3 for recycling. The residual liquid generated after distillation is discharged into the concentrated waste oil tank 14. The concentrated waste oil in the concentrated waste oil tank 14 has a water content ≤0.1%, which meets the raw material requirements of the titanium tetrachloride vanadium removal process.
[0045] S4 Waste Oil Reuse: The concentrated waste oil in the concentrated waste oil tank 14 is transported to the titanium tetrachloride production process through a pipeline and mixed into the vanadium removal oil used for crude titanium tetrachloride in a certain proportion, so as to realize the resource utilization of waste oil, reduce production costs, and reduce pollutant emissions.
[0046] Throughout the cleaning process, the parameter acquisition module of the pipeline and control system collects real-time data on the temperature and liquid level of the cleaning tank 2, the temperature and pressure of the distillation kettle 13, and the temperature and ventilation rate of the ventilation drying box 4. The logic operation module automatically adjusts the cleaning parameters according to the preset algorithm C=f(T,L,t), where C is the comprehensive score of cleaning effect, T is the cleaning temperature, L is the cleaning agent level, and t is the cleaning time. The execution control module precisely controls the flow rate of the cleaning agent through an electromagnetic flow meter, with a flow error ≤±2%. The system has a fault alarm function, automatically stopping liquid feeding when the liquid level in the accumulation tanks 8 to 12 reaches the upper limit of 80%, and automatically depressurizing when the pressure in the distillation kettle 13 exceeds 0.08MPa. At the same time, the system is equipped with a data storage module, which can record the process parameters and test results of each cleaning, realizing product quality traceability.
[0047] Example 1
[0048] System preparation: Ensure that there is sufficient cleaning agent in the cleaning agent storage tank. Use trichloroethylene or isoalkane solvent as the cleaning agent. Confirm that the collection tanks #1 to #5 are empty. Check that all components of the pipeline and control system are operating normally.
[0049] Raw material to be processed: When a titanium plant was crushing a 5-ton sponge titanium block, the hydraulic oil pipe of the crusher ruptured, resulting in about 100 kilograms of sponge titanium blocks being contaminated by hydraulic oil.
[0050] Multi-stage countercurrent cleaning: Oil-containing sponge titanium is fed into the cleaning tank via a feeding mechanism. Cleaning agent is injected into the tank from the cleaning agent storage tank by opening the valve, maintaining the cleaning agent level 15cm above the sponge titanium pile surface. The stirring device is started at a stirring speed of 40 rpm. The first cleaning lasts 40 minutes. After cleaning, the oil-rich waste cleaning solution is pumped into the No. 1 collection tank. For the second cleaning, fresh cleaning agent is injected from the cleaning agent storage tank, and the cleaning lasts 30 minutes. The cleaning solution is then discharged into the No. 2 collection tank. The third to fifth cleanings are performed sequentially, with cleaning times of 25 minutes, 25 minutes, and 20 minutes respectively. The cleaning solutions are then discharged into the No. 3, 4, and 5 collection tanks respectively. The operator samples the liquid discharged into the No. 5 collection tank; when it becomes clear and transparent, the sponge titanium is considered clean.
[0051] Evaporation and drying: Remove the cleaned sponge titanium from the cleaning tank and send it into a ventilated drying oven. Let it stand for 12 hours at 30℃ and a ventilation rate of 2m / s until the cleaning agent has completely evaporated. The residual amount of cleaning agent was tested to be <10mg / kg.
[0052] Solvent recovery: The distillation process is initiated, pumping the high-concentration waste liquid from collection tanks #1 and #2 into the distillation kettle. The distillation temperature is controlled at 87±2℃, and the system pressure at 0.06MPa. The cleaning agent vapor is liquefied through a pre-condenser heat exchanger and condenser, then enters the condensate recovery tank, and finally returned to the cleaning agent storage tank for recycling. Testing shows that the cleaning agent recovery rate is ≥96%, and the purity is ≥99.2%. The concentrated waste oil at the bottom of the distillation kettle is discharged into the concentrated waste oil tank.
[0053] Waste oil utilization: Waste oil in the concentrated waste oil tank is pumped quantitatively to the titanium tetrachloride vanadium removal section for reuse according to process requirements.
[0054] Example 2
[0055] System preparation: Ensure that there is sufficient trichloroethylene cleaning agent in the cleaning agent storage tank, confirm that the No. 1 and No. 2 collection tanks are empty, and that the No. 3, No. 4 and No. 5 collection tanks contain the remaining cleaning solution after the previous batch of cleaning. Check that the pipeline and control system are operating normally.
[0056] Raw material to be processed: When a titanium plant was rolling a 5-ton sponge titanium block, the hydraulic oil pipe of the crusher ruptured, resulting in about 300 kilograms of sponge titanium block being contaminated by hydraulic oil.
[0057] Multi-stage countercurrent cleaning: Oil-containing titanium sponge is fed into the cleaning tank via a feeding mechanism. Cleaning agent is injected into the cleaning tank from tank #3 by opening the valve. The stirring device is started at a speed of 35 rpm for 30 minutes, and the cleaning solution is discharged into tank #1. For the second cleaning, cleaning agent is injected from tank #4, and the tank is stirred for 25 minutes. The cleaning solution is discharged into tank #2. For the third cleaning, cleaning agent is injected from tank #5, and the tank is stirred for 25 minutes. The cleaning solution is discharged into tank #3. For the fourth cleaning, fresh cleaning agent is injected from the cleaning agent storage tank, and the tank is stirred for 20 minutes. The cleaning solution is discharged into tank #4. For the fifth cleaning, fresh cleaning agent is injected from the cleaning agent storage tank, and the tank is stirred for 20 minutes. The cleaning solution is discharged into tank #5. The operator samples the liquid discharged into tank #5; when it becomes clear and transparent, the titanium sponge is considered clean.
[0058] Evaporation drying: The cleaned sponge titanium was removed from the cleaning tank and sent to a ventilated drying oven. It was dried for 10 hours at 35°C and a ventilation rate of 1.5 m / s. The residual amount of cleaning agent was tested to be <10 mg / kg.
[0059] Solvent recovery: Start the distillation process, pump the high-concentration waste liquid from the No. 1 and No. 2 collection tanks into the distillation kettle, control the distillation temperature at 87±2℃, and the system pressure at 0.06MPa. The cleaning agent vapor is condensed and liquefied and then sent back to the cleaning agent storage tank for recycling. The cleaning agent recovery rate is ≥95%, and the purity is ≥99%. The distillation residue is discharged into the concentrated waste oil tank.
[0060] Waste oil utilization: Waste oil in the concentrated waste oil tank is pumped quantitatively to the titanium tetrachloride vanadium removal section for reuse according to process requirements.
[0061] The results are verified as follows:
[0062] After cleaning, the sponge titanium was tested and found to have carbon contents of 0.022% and 0.028%, respectively, with normal nitrogen and oxygen contents, meeting the second-grade standard. The trichloroethylene recovery rate remained stable at over 95%, and the purity met the requirements for reuse. The concentrated waste oil performed normally in the vanadium removal experiment, indicating its suitability for resource utilization. Compared with traditional water washing methods, this invention generates no wastewater, reduces drying energy consumption by approximately 70%, and has a comprehensive cleaning cost of approximately 560-600 yuan / ton of oil-based sponge titanium, demonstrating good economic and environmental benefits.
[0063] The cleaning method for oily sponge titanium of this invention boasts high cleaning efficiency and thorough cleaning effect, effectively restoring the product value of oil-contaminated sponge titanium. This invention selects alkane or halogenated hydrocarbon organic solvents that are completely miscible with mineral oil as the cleaning agent. These cleaning agents can quickly penetrate into the porous structure of sponge titanium, fully dissolving the oil contaminants within the pores. Combined with a multi-stage countercurrent cleaning process, along with the synergistic effect of ultrasonic assistance and mechanical stirring, the oil removal efficiency is significantly improved, ultimately achieving an oil removal rate of over 99%. The residual cleaning agent on the surface of the cleaned sponge titanium is ≤10mg / kg, and the carbon content can be reduced to 0.022%-0.028%, meeting the secondary product standard. This successfully transforms contaminated sponge titanium, which would otherwise be scrapped, into a qualified product that meets downstream usage requirements, significantly reducing the economic losses for enterprises.
[0064] The cleaning method for sponge titanium oil in this invention produces no secondary pollution throughout the entire process, achieving a closed-loop cycle and efficient resource utilization. The entire cleaning and recycling process requires no water, eliminating the generation of oily wastewater at its source and avoiding subsequent wastewater treatment costs and environmental pressures. The oily cleaning solution achieves efficient recovery of the cleaning agent through distillation, with a single-pass recovery rate of ≥95% and a purity of ≥99%. This recovered cleaning agent can be directly returned to the cleaning system for recycling, significantly reducing the consumption cost of the cleaning agent. The concentrated waste oil generated after distillation can also be transported to the titanium tetrachloride production process as a raw material for vanadium removal oil, thus solving the problem of hazardous waste disposal and saving raw material costs for upstream production processes, fully aligning with the development concept of green manufacturing.
[0065] The cleaning method for oily titanium sponges of this invention significantly reduces energy consumption and overall production costs, demonstrating strong feasibility for industrial application. The cleaned titanium sponges can be dried in a ventilated drying oven thanks to the natural volatility of the cleaning agent, eliminating the high-temperature drying step required by traditional water washing methods. This reduces drying energy consumption by approximately 70% compared to traditional methods. Simultaneously, the system employs a programmable logic controller for centralized control, enabling real-time acquisition and automatic adjustment of key process parameters such as temperature, liquid level, and pressure. This not only ensures the stability and consistency of the cleaning effect but also achieves full traceability of product quality. Furthermore, the multi-stage cleaning process prioritizes the use of recycled cleaning agents with low oil content, further reducing the amount of fresh cleaning agent required. Calculations show that the overall cleaning cost of this invention is only 560-600 yuan / ton of oily titanium sponges, creating higher economic benefits for enterprises while improving product quality.
[0066] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.
Claims
1. A cleaning method for sponge titanium oil, comprising a cleaning and recovery system including a cleaning tank (2), a cleaning agent storage tank (3), 1# to 5# liquid collection tanks (8) to (12), a distillation kettle (13), a condenser (6), a condensate recovery tank (7), a concentrated waste oil tank (14), a ventilation drying oven (4), and pipelines and a control system connecting the various devices, characterized in that, Includes the following steps: S1 Multi-stage Countercurrent Cleaning: The oil-containing sponge titanium is loaded into the cleaning tank (2), and the cleaning agent is injected from the cleaning agent storage tank (3) in stages for at least two cleanings. Each cleaning solution is discharged into the corresponding serial numbered collection tanks (8) to (12); the amount of cleaning agent used satisfies the formula ,in The mass ratio coefficient of the cleaning agent to the titanium sponge is 5-10 L / kg. For the mass of oil-containing sponge titanium, The cross-sectional area of the cleaning tank (2) is... The cleaning agent level is 10-20cm above the surface of the titanium sponge pile. S2 Evaporation Drying: The cleaned sponge titanium was transferred into a ventilated drying oven (4) and dried by natural evaporation. The drying endpoint met the residual amount formula. ,in This refers to the residual cleaning agent content on the surface of the titanium sponge, expressed in mg / kg. For the quality of residual cleaning agent, The mass of the dried sponge titanium; S3 Solvent Recovery: The high-oil-concentration cleaning solution from the 1# to 3# collection tanks (8) to (10) is pumped into the distillation kettle (13), heated and distilled, and then condensed by the condenser (6) to obtain pure cleaning agent. The cleaning agent recovery rate satisfies the formula: ； in The single distillation recovery rate of the cleaning agent. To recover the volume of cleaning agent, The volume of the cleaning agent in the cleaning solution before distillation is the volume of the cleaning agent. The recovered cleaning agent is returned to the cleaning agent storage tank (3) for recycling, and the distillation residue is discharged into the concentrated waste oil tank (14). S4 Waste Oil Reuse: The concentrated waste oil in the concentrated waste oil tank (14) is transported to the titanium tetrachloride production process and mixed into the vanadium removal oil used for crude titanium tetrachloride vanadium removal.
2. The cleaning method for sponge titanium oil according to claim 1, characterized in that, The cleaning process in step S1 is repeated five times. The first cleaning solution is discharged into the No. 1 collection tank (8), the second cleaning solution is discharged into the No. 2 collection tank (9), the third cleaning solution is discharged into the No. 3 collection tank (10), the fourth cleaning solution is discharged into the No. 4 collection tank (11), and the fifth cleaning solution is discharged into the No. 5 collection tank (12). Whether the cleaning solution in the No. 5 collection tank (12) is clear and transparent is used as the criterion for judging whether the sponge titanium is qualified for cleaning.
3. The cleaning method for sponge titanium oil according to claim 1, characterized in that, The cleaning agent is selected from one or a mixture of several alkane solvents and halogenated hydrocarbon solvents; the alkane solvent is an isoalkane solvent oil with a carbon chain length of C8-C10 and a boiling point range of 80-120℃; the halogenated hydrocarbon solvent is trichloroethylene with a purity of ≥99.5% and a boiling point of 86-88℃; the boiling point of the cleaning agent is 50-200℃ lower than the boiling point of the mineral oil to be removed.
4. The cleaning method for sponge titanium oil according to claim 1, characterized in that, In step S1, ultrasonic-assisted cleaning is applied during the cleaning process, with an ultrasonic frequency of 20kHz to 40kHz; the cleaning temperature is 25℃ at room temperature or heated to 60-80% of the boiling point of the cleaning agent, corresponding to a temperature range of 40-60℃; the cleaning time is set in gradients, with the first cleaning time being 30-40min and the second to fifth cleaning times being 20-30min.
5. The cleaning method for sponge titanium oil according to claim 1, characterized in that, The cleaning agent must simultaneously meet the following characteristics: complete miscibility with mineral oil, no chemical reaction with sponge titanium, and moderate saturated vapor pressure at room temperature. The miscibility criterion for the cleaning agent and mineral oil is that no stratification occurs after mixing and standing for 12 hours, and the difference in boiling points between the cleaning agent and mineral oil satisfies the formula... ,in The boiling point of the mineral oil to be removed, The boiling point of the cleaning agent. The value range is 50-200℃; the carbon chain distribution uniformity of the alkane solvent is ≥90%, and the impurity content of the halogenated hydrocarbon solvent is ≤0.5%; the purity of the cleaning agent is detected by gas chromatography, and the detection conditions are capillary column temperature 80-120℃, carrier gas is nitrogen, and flow rate is 1mL / min.
6. The cleaning method for sponge titanium oil according to claim 1, characterized in that, The cleaning process in step S1 is accompanied by a stirring operation at a speed of 30-60 r / min. The stirring paddle has an anchor structure, and the distance between the paddle blade and the inner wall of the cleaning tank (2) is 5-10 cm. The cleaning agent level is monitored in real time by a level sensor to ensure that it is always 10-20 cm higher than the surface of the sponge titanium pile to prevent the sponge titanium from being exposed and causing cleaning dead corners. The oil removal rate of the cleaning effect satisfies the formula: ； in, To determine the quality of the oil stains adhering to the surface of the sponge titanium before cleaning, The quality of residual oil on the surface of the sponge titanium after cleaning is determined. When the oil content on the surface of the sponge titanium is >5%, the first cleaning time is extended to 40-45 minutes, and the ultrasonic power is increased to 120% of the rated power.
7. The cleaning method for sponge titanium oil according to claim 1, characterized in that, The evaporation drying conditions in step S2 are as follows: the ventilation drying box (4) has an internal airflow distribution plate to ensure that the airflow is uniformly blowing on the surface of the sponge titanium. The temperature inside the box is controlled by a PID temperature control system with a temperature fluctuation range of ≤±2℃. The ventilation rate is 1-3m / s and the drying time is 8-24h. The residual amount of cleaning agent on the surface of the sponge titanium is detected by pyrolysis-gas chromatography. The detection steps are to take 10g of sponge titanium sample and place it in a pyrolysis furnace, pyrolyze it at 300℃ for 30min, and separate and detect the pyrolysis gas by a gas chromatograph. The drying uniformity judgment standard is that the difference in residual amount of cleaning agent in different parts of the sponge titanium is ≤2mg / kg. During the drying process, the tail gas of the ventilation drying box (4) is discharged after being treated by activated carbon adsorption. The adsorbent can be recycled and regenerated after it is saturated.
8. The cleaning method for sponge titanium oil according to claim 1, characterized in that, The distillation conditions in step S3 are as follows: the heating method is selected according to the processing scale; electric heating is used for small-scale processing, and steam heating is used for large-scale processing; the distillation temperature is ±5℃ of the boiling point of the cleaning agent; the distillation system pressure is at atmospheric pressure or under reduced pressure, with the reduced pressure value being 0.05-0.08MPa; during the distillation process, an explosion-proof temperature sensor is used to monitor the temperature inside the vessel in real time, and the over-temperature alarm threshold is set to the boiling point of the cleaning agent +10℃; the cleaning agent recovery rate is ≥95%, and the purity is ≥99%; the purity is detected by gas chromatography, and the purity is calculated using the area normalization method; the distillation efficiency satisfies the formula... ,in This refers to the volume of cleaning agent recovered per unit time. The feed volume of the distillation vessel (13) is... The distillation time is specified; the concentrated waste oil after distillation has a water content of ≤0.1%, which meets the raw material requirements for the titanium tetrachloride vanadium removal process.
9. The cleaning method for sponge titanium oil according to claim 2, characterized in that, In the five-stage cleaning process of step S1, the cleaning agent is injected in a combination of recycled cleaning agent and fresh cleaning agent. The first to third cleaning uses the low-oil-content recycled cleaning agent in the No. 4 and No. 5 liquid collection tanks (11) to (12). The fourth to fifth cleaning uses the fresh cleaning agent in the cleaning agent storage tank (3). The cleaning time gradient is dynamically adjusted according to the oil concentration. When the oil concentration is 1%-3%, the first cleaning time is 30 min and the second to fifth cleaning time is 20 min. When the oil concentration is 3%-5%, the first cleaning time is 35 min and the second to fifth cleaning time is 25 min. The ultrasonic cleaning and mechanical stirring work together. When the ultrasonic frequency is 20 kHz, the stirring speed is matched with 30 r / min. When the ultrasonic frequency is 40 kHz, the stirring speed is matched with 60 r / min to enhance the penetration effect of the cleaning agent in the porous structure of sponge titanium.
10. The cleaning method for sponge titanium oil according to claim 1, characterized in that, The pipeline and control system is centrally controlled by a programmable logic controller (PLC). The PLC integrates a parameter acquisition module, a logic operation module, and an execution control module. The parameter acquisition module collects data in real time, including the temperature and liquid level of the cleaning tank (2), the temperature and pressure of the distillation vessel (13), and the temperature and ventilation rate of the ventilation drying box (4). The logic operation module performs the operation according to a preset algorithm. Automatically adjust cleaning parameters, among which To determine the overall cleaning effect, For cleaning temperature, This refers to the cleaning agent level. The system is designed for cleaning time. The control module enables the directional delivery of cleaning agent between the cleaning tank (2), cleaning agent storage tank (3), liquid collection tank (8) to (12), and distillation kettle (13). The flow rate of the cleaning agent is precisely controlled by an electromagnetic flow meter, with a flow rate error of ≤±2%. The system has a fault alarm function. When the liquid level in the liquid collection tank (8) to (12) reaches the upper limit of 80%, the liquid feeding will automatically stop. When the pressure in the distillation kettle (13) exceeds 0.08MPa, the pressure will automatically be released. At the same time, the system is equipped with a data storage module, which can record the process parameters and test results of each cleaning, and realize product quality traceability.