Automatic control system and control method for acidolysis premixing process in production of titanium dioxide by sulfuric acid method

Abstract

The invention provides an automatic control system for an acidolysis premixing process in production of titanium dioxide by a sulfuric acid method, which belongs to the technical field of chemical automation control and comprises a concentrated sulfuric acid metering tank, a premixing ore bin, an acidolysis premixing pot and a plurality of acidolysis pots, the bottom of the pre-mixing ore bin is communicated with the top of the acidolysis pre-mixing pot through a pre-mixing ore bin blanking valve and a pre-mixing ore bin star-shaped blanking valve in sequence; an acidolysis premixing pot stirrer is arranged in the acidolysis premixing pot, and the bottom of the acidolysis premixing pot is communicated with a plurality of acidolysis pots through premixing pot bottom valves. According to the invention, errors during manual operation can be reduced; the time of each process can be accurately controlled; operation is easy and convenient, the automation degree is high, the safety coefficient is high, stability is good, automatic control over procedures is truly achieved, labor intensity is relieved, and production cost is reduced. The invention also relates to a control method of the automatic control system for the acidolysis premixing process in the production of the titanium dioxide by the sulfuric acid method.

Description

Technical Field

[0001] This invention relates to the field of chemical automation control technology, and more specifically, to an automated control system for the acidolysis premixing process in the sulfuric acid process for titanium dioxide production. This invention also relates to a control method for this automated control system for the acidolysis premixing process in the sulfuric acid process for titanium dioxide production. Background Technology

[0002] Currently, the automation level of conventional acid hydrolysis premixing processes in the industry is low, with control relying on manual operation on-site and partial remote manual control. The main problems with manual control of the acid hydrolysis premixing process are as follows:

[0003] 1. The acid ore premixing process has strict requirements on the amount of concentrated sulfuric acid and mineral powder added, and strict requirements on temperature control during the premixing process. The weight of ore and concentrated sulfuric acid added is determined by calculation based on the acid ore ratio and reaction concentration formula. If the valve is not closed in time during manual operation, the amount added will be inaccurate, which will affect the product quality. If the valve is not closed or the pump is not stopped, it will cause leakage of hazardous chemicals and material loss, and in severe cases, personnel injury.

[0004] 2. Manual feeding is prone to overflowing or shortages, affecting production efficiency. In addition, concentrated sulfuric acid is a hazardous chemical, and sulfuric acid leakage poses a significant safety hazard.

[0005] Therefore, it is necessary to develop an automated control system for the acidolysis premixing process in the sulfuric acid process for titanium dioxide production. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the above-mentioned background technology and to provide an automated control system for the acidolysis premixing process in the production of titanium dioxide using the sulfuric acid process.

[0007] To achieve the aforementioned objective, the technical solution of the present invention is as follows: an automated control system for the acidolysis premixing process in the sulfuric acid process for titanium dioxide production, characterized in that it includes a concentrated sulfuric acid metering tank, a premixed ore bin, an acidolysis premixing pot, and multiple acidolysis pots; the bottom side of the concentrated sulfuric acid metering tank is connected to the top of the acidolysis premixing pot via a concentrated sulfuric acid metering tank outlet valve; the bottom of the premixed ore bin is connected to the top of the acidolysis premixing pot via a premixed ore bin discharge valve and a premixed ore bin star-shaped discharge valve in sequence.

[0008] The acid hydrolysis premixing pot is equipped with an acid hydrolysis premixing pot stirrer, and the bottom of the acid hydrolysis premixing pot is connected to multiple acid hydrolysis pots through a premixing pot bottom valve.

[0009] In the above technical solution, a concentrated sulfuric acid weight sensor is installed at the bottom of the concentrated sulfuric acid metering tank.

[0010] In the above technical solution, a premixed ore bin weight sensor is provided on the side of the premixed ore bin.

[0011] In the above technical solution, a weight sensor for the acid hydrolysis premixing pot is provided at the bottom, and a temperature sensor for the acid hydrolysis premixing pot is provided on the side.

[0012] In the above technical solution, there are three acid hydrolysis pots: a first acid hydrolysis pot, a second acid hydrolysis pot, and a third acid hydrolysis pot; the bottom valve of the premixing pot is connected to the first acid hydrolysis pot via a transfer ball valve of the first acid hydrolysis pot, to the second acid hydrolysis pot via a transfer ball valve of the second acid hydrolysis pot, and to the third acid hydrolysis pot via a transfer ball valve of the third acid hydrolysis pot.

[0013] To achieve the aforementioned second objective, the technical solution of the present invention is: a control method for an automated control system of the acidolysis premixing process in the sulfuric acid process for titanium dioxide production, characterized by comprising the following steps:

[0014] Step 1: Press the program auto button to reset all timers and the step sequence;

[0015] Step 2: Press the program start button to initialize all devices;

[0016] Step 3: After the concentrated sulfuric acid weight sensor detects that the weight of the concentrated sulfuric acid metering vessel is greater than 27000KG, a judgment is made after 20 seconds;

[0017] Step 4: Open the outlet valve of the concentrated sulfuric acid metering tank. When the weight of acid dispensed in one operation equals the set primary acid ratio multiplied by the total weight of acid dispensed, close the outlet valve of the concentrated sulfuric acid metering tank; the secondary acid ratio + primary acid ratio = 100%.

[0018] Step 5: When the premixed ore bin weight sensor detects that the premixed ore bin weight is greater than the set ore weight, manually click the confirm ore weight button and record the current ore weight of the premixed ore bin as T;

[0019] Step 6: When the temperature sensor of the acidolysis premixing pot detects that the temperature of the acidolysis premixing pot is less than the set temperature by 3, open the premixed ore bin discharge valve.

[0020] Step 7: Change the operating frequency of the agitator in the acid hydrolysis premixing pot to 40Hz;

[0021] Step 8: Start the star-shaped discharge valve of the pre-mineral bin;

[0022] Step 9: When the temperature sensor of the acidolysis premixing pot detects that the temperature of the acidolysis premixing pot is greater than the set temperature by 1, and at the same time, the user manually confirms that the temperature has been reached and presses the "discharge" button to enter the password.

[0023] Step 10: Close the premixed ore bin discharge valve;

[0024] Step 11: When the T-premixed ore bin weight sensor detects that the premixed ore bin weight is ≥ the set ore weight M 矿 Stop the star-shaped discharge valve of the pre-mineral bin, and start the premixing timer;

[0025] Step 12: The premixing time of the acid hydrolysis premixing pot reaches the time set by 1 or the temperature of the acid hydrolysis premixing pot is greater than the temperature set value;

[0026] Step 13: Start the premix transfer program and select the first acid hydrolysis pot, the second acid hydrolysis pot, and the third acid hydrolysis pot;

[0027] Step 14: Taking the selection of the first acid hydrolysis tank as an example;

[0028] Step 15: Determine that the transfer ball valves of the second and third acid hydrolysis pots are in the closed state;

[0029] Step 16: Open the transfer ball valve of the first acid hydrolysis pot;

[0030] Step 17: At the same time the first acidolysis pot transfer ball valve opens, the compressed air flow rate of the acidolysis premix pot reaches the set value;

[0031] Step 18: Open the bottom valve of the premixing pot and change the operating frequency of the agitator of the acid hydrolysis premixing pot to 15Hz, and start the material transfer timing;

[0032] Step 19: After the material transfer time reaches the set time, manually confirm that the material transfer is complete, and the premix material transfer process is completed;

[0033] Step 20: Open the outlet valve of the concentrated sulfuric acid metering tank;

[0034] Step 21: When the weight of the secondary acid supply equals the set secondary acid ratio × the total weight of the acid supply, close the outlet valve of the concentrated sulfuric acid metering tank;

[0035] Step 22: Close the bottom valve of the premixing pot and stop the agitator of the acid hydrolysis premixing pot; close the transfer ball valve of the first acid hydrolysis pot;

[0036] Step 23: Program ends.

[0037] Compared with the prior art, the present invention has the following advantages:

[0038] 1) This invention can reduce errors during manual operation; it can precisely control the time of each process; it is easy to operate, highly automated, safe, and stable, and truly realizes the automated control of the process, which not only reduces labor intensity but also reduces production costs.

[0039] 2) This invention enables one-click start of the acid hydrolysis premixing process; it also enables automatic control and cyclic process of the acid hydrolysis premixing process.

[0040] 3) This invention enables the automatic calculation of sulfuric acid and concentrated waste acid in the acidolysis premixing process, as well as the automatic metering and feeding of sulfuric acid and mineral powder, thus avoiding production instability caused by parameter mismatch. Attached Figure Description

[0041] Figure 1 This is a schematic diagram of the structure of the present invention.

[0042] Among them, 100-concentrated sulfuric acid metering tank, 110-concentrated sulfuric acid metering tank outlet valve, 120-concentrated sulfuric acid weight sensor, 200-premixed ore bin, 210-premixed ore bin discharge valve, 220-premixed ore bin star discharge valve, 230-premixed ore bin weight sensor, 300-acidolysis premixing pot, 400-acidolysis pot, 310-acidolysis premixing pot agitator, 320-premixing pot bottom valve, 330-acidolysis premixing pot weight sensor, 340-acidolysis premixing pot temperature sensor, 410-first acidolysis pot, 411-first acidolysis pot transfer ball valve, 420-second acidolysis pot, 421-second acidolysis pot transfer ball valve, 430-third acidolysis pot, 431-third acidolysis pot transfer ball valve. Detailed Implementation

[0043] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings, but these descriptions are not intended to limit the invention and are merely illustrative. The advantages of the present invention will become clearer and easier to understand through this description.

[0044] Referring to the accompanying drawings, an automated control system for the acidolysis premixing process in the sulfuric acid process for titanium dioxide production is characterized by comprising a concentrated sulfuric acid metering tank 100, a premixed ore bin 200, an acidolysis premixing pot 300, and multiple acidolysis pots 400; the bottom side of the concentrated sulfuric acid metering tank 100 is connected to the top of the acidolysis premixing pot 300 via a concentrated sulfuric acid metering tank outlet valve 110; the bottom of the premixed ore bin 200 is connected to the top of the acidolysis premixing pot 300 via a premixed ore bin discharge valve 210 and a premixed ore bin star-shaped discharge valve 220 in sequence;

[0045] The acid hydrolysis premixing pot 300 is equipped with an acid hydrolysis premixing pot stirrer 310, and the bottom of the acid hydrolysis premixing pot 300 is connected to multiple acid hydrolysis pots 400 through a premixing pot bottom valve 320.

[0046] A concentrated sulfuric acid weight sensor 120 is installed at the bottom of the concentrated sulfuric acid metering tank 100.

[0047] A premixed ore bin weight sensor 230 is installed on the side of the premixed ore bin 200.

[0048] The acid hydrolysis premixing pot 300 is equipped with an acid hydrolysis premixing pot weight sensor 330 at the bottom and an acid hydrolysis premixing pot temperature sensor 340 on the side.

[0049] There are three acid hydrolysis pots 400: a first acid hydrolysis pot 410, a second acid hydrolysis pot 420, and a third acid hydrolysis pot 430. The bottom valve 320 of the premixing pot is connected to the first acid hydrolysis pot 410 through the first acid hydrolysis pot transfer ball valve 411, to the second acid hydrolysis pot 421 through the second acid hydrolysis pot transfer ball valve 421, and to the third acid hydrolysis pot 431 through the third acid hydrolysis pot transfer ball valve 431.

[0050] In practical use, the automated control method of the present invention includes the following steps:

[0051] Step 1: Press the program auto button to reset all timers and the step sequence;

[0052] Step 2: Press the program start button to initialize all devices;

[0053] Step 3: After the concentrated sulfuric acid weight sensor 120 detects that the weight of the concentrated sulfuric acid metering tank 100 is greater than 27000KG, a judgment is made after 20 seconds;

[0054] Step 4: Open the outlet valve 110 of the concentrated sulfuric acid metering tank. When the weight of acid dispensed in one operation equals the set primary acid ratio multiplied by the total weight of acid dispensed, close the outlet valve 110 of the concentrated sulfuric acid metering tank; the secondary acid ratio + primary acid ratio = 100%.

[0055] Step 5: When the premixed ore bin weight sensor 230 detects that the weight of the premixed ore bin 200 is greater than the set ore weight, manually click the ore weight confirmation button and record the current ore weight of the premixed ore bin 200 as T;

[0056] Step 6: When the acidolysis premixing pot temperature sensor 340 detects that the temperature of the acidolysis premixing pot 300 is lower than the set temperature 3, open the premixed ore bin discharge valve 210.

[0057] Step 7: Change the operating frequency of the acid hydrolysis premixing tank stirrer 310 to 40Hz;

[0058] Step 8: Start the pre-mineral bin star valve 220;

[0059] Step 9: When the temperature sensor 340 of the acid hydrolysis premixing pot detects that the temperature of the acid hydrolysis premixing pot 300 is greater than the set temperature 1, the user manually confirms that the temperature has been reached and presses the "discharge" button to enter the password.

[0060] Step 10: Close the premixed ore bin discharge valve 210;

[0061] Step 11: When the T-premixed ore bin weight sensor 230 detects that the weight of the premixed ore bin 200 is greater than or equal to the set ore weight M 矿 Stop the star valve 220 in the pre-mineral bin, and start the premixing timer;

[0062] Step 12: The premixing time of the acid hydrolysis premixing pot 300 reaches the time set by 1 or the temperature of the acid hydrolysis premixing pot 300 is greater than the temperature set value;

[0063] Step 13: Start the premix transfer program and select the first acid hydrolysis tank 410, the second acid hydrolysis tank 420 and the third acid hydrolysis tank 430;

[0064] Step 14: Taking the first acid hydrolysis tank 410 as an example;

[0065] Step 15: Determine that the second acid hydrolysis pot transfer ball valve 421 and the third acid hydrolysis pot transfer ball valve 431 are in the closed state;

[0066] Step 16: Open the first acid hydrolysis pot transfer ball valve 411;

[0067] Step 17: At the same time as the first acid hydrolysis pot transfer ball valve 411 is opened, the compressed air flow rate of the acid hydrolysis premixing pot 300 reaches the set value;

[0068] Step 18: Open the bottom valve 320 of the premixing pot and change the operating frequency of the agitator 310 of the acid hydrolysis premixing pot to 15Hz, and start the material transfer timing;

[0069] Step 19: After the material transfer time reaches the set time, manually confirm that the material transfer is complete, and the premix material transfer process is completed;

[0070] Step 20: Open the outlet valve 110 of the concentrated sulfuric acid metering tank;

[0071] Step 21: When the weight of the secondary acid supply is equal to the set secondary acid ratio × the total weight of the acid supply, close the outlet valve 110 of the concentrated sulfuric acid metering tank;

[0072] Step 22: Close the bottom valve 320 of the premixing pot and stop the agitator 310 of the acid hydrolysis premixing pot; close the transfer ball valve 411 of the first acid hydrolysis pot;

[0073] Step 23: Program ends;

[0074] Let the weight of the ore be a given constant, M. 矿 The concentration of sulfuric acid in the acidolysis reaction is set to a given constant, η%. In the next step, the acidolysis reaction is initiated using process water, with a specific gravity of 1 ton / m³. The given acid-ore mass ratio during the reaction is b.

[0075] Assume the required weight of concentrated sulfuric acid is x tons; the required weight of process water is y tons; then

[0076] (1)

[0077] (2)

[0078] Calculate x = b × M_ore / w% from (2). Substitute the calculated result of x into equation 1 to get...

[0079] y = b × M_ore × (1 / η% - 1 / w%)

[0080] The total weight of concentrated sulfuric acid, calculated based on the above, is b × M. 矿 / w% tons, at the set ore weight M 矿 When a constant is given, the total weight of concentrated sulfuric acid can be determined. This invention avoids production instability caused by parameter misalignment by automatically metering and feeding sulfuric acid and mineral powder.

[0081] All other unspecified parts belong to the prior art.

[0082] All other unspecified parts belong to the prior art.

Claims

1. An automated control system for the acidolysis premixing process in the sulfuric acid process for titanium dioxide production, characterized in that: It includes a concentrated sulfuric acid metering tank (100), a premixed ore bin (200), an acidolysis premixing pot (300), and multiple acidolysis pots (400); the bottom side of the concentrated sulfuric acid metering tank (100) is connected to the top of the acidolysis premixing pot (300) through a concentrated sulfuric acid metering tank outlet valve (110); the bottom of the premixed ore bin (200) is connected to the top of the acidolysis premixing pot (300) in sequence through a premixed ore bin discharge valve (210) and a premixed ore bin star discharge valve (220); The acid hydrolysis premixing pot (300) is equipped with an acid hydrolysis premixing pot stirrer (310), and the bottom of the acid hydrolysis premixing pot (300) is connected to multiple acid hydrolysis pots (400) through a premixing pot bottom valve (320).

2. The automated control system for the acidolysis premixing process in the sulfuric acid process for titanium dioxide production according to claim 1, characterized in that: A concentrated sulfuric acid weight sensor (120) is installed at the bottom of the concentrated sulfuric acid metering tank (100).

3. The automated control system for the acidolysis premixing process in the sulfuric acid process for titanium dioxide production according to claim 2, characterized in that: A premixed ore bin weight sensor (230) is installed on the side of the premixed ore bin (200).

4. The automated control system for the acidolysis premixing process in the sulfuric acid process for titanium dioxide production according to claim 3, characterized in that: The acid hydrolysis premixing pot (300) is equipped with a weight sensor (330) at the bottom and a temperature sensor (340) on the side.

5. The automated control system for the acidolysis premixing process in the sulfuric acid process for titanium dioxide production according to claim 1, characterized in that: There are three acid hydrolysis pots (400): a first acid hydrolysis pot (410), a second acid hydrolysis pot (420), and a third acid hydrolysis pot (430). The bottom valve (320) of the premixing pot is connected to the first acid hydrolysis pot (410) through the first acid hydrolysis pot transfer ball valve (411), to the second acid hydrolysis pot (420) through the second acid hydrolysis pot transfer ball valve (421), and to the third acid hydrolysis pot (430) through the third acid hydrolysis pot transfer ball valve (431).

6. A control method for an automated control system of the acidolysis premixing process in the sulfuric acid process for titanium dioxide production, characterized in that, Includes the following steps: Step 1: Press the program auto button to reset all timers and the step sequence; Step 2: Press the program start button to initialize all devices; Step 3: When the concentrated sulfuric acid weight sensor (120) detects that the weight of the concentrated sulfuric acid metering vessel (100) is greater than 27000KG, a judgment is made after 20 seconds; Step 4: Open the outlet valve (110) of the concentrated sulfuric acid metering tank. When the weight of acid dispensed in one operation equals the set primary acid ratio multiplied by the total weight of acid dispensed, close the outlet valve (110) of the concentrated sulfuric acid metering tank; the secondary acid ratio + primary acid ratio = 100%. Step 5: When the premixed ore bin weight sensor (230) detects that the weight of the premixed ore bin (200) is greater than the set ore weight, manually click the ore weight confirmation button and record the current ore weight of the premixed ore bin (200) as T; Step 6: When the acidolysis premixing pot temperature sensor (340) detects that the temperature of the acidolysis premixing pot (300) is less than the set temperature 3, open the premixed ore bin discharge valve (210); Step 7: Change the operating frequency of the acid hydrolysis premixing tank stirrer (310) to 40Hz; Step 8: Start the pre-mineral bin star valve (220); Step 9: When the temperature sensor (340) of the acid hydrolysis premixing pot detects that the temperature of the acid hydrolysis premixing pot (300) is greater than the set temperature by 1, and at the same time, manually confirm that the temperature has been reached and press the discharge button to enter the password; Step 10: Close the premixed ore bin discharge valve (210); Step 11: When the T-premixed ore bin weight sensor (230) detects that the weight of the premixed ore bin (200) is greater than or equal to the set ore weight M 矿 Stop the star valve (220) of the pre-mineral bin, and start the premixing time countdown; Step 12: The premixing time of the acid hydrolysis premixing pot (300) reaches the time setting 1 or the temperature of the acid hydrolysis premixing pot (300) is greater than the temperature setting value; Step 13: Start the premix transfer program and select the first acid hydrolysis tank (410), the second acid hydrolysis tank (420), and the third acid hydrolysis tank (430); Step 14: Taking the first acid hydrolysis vessel (410) as an example; Step 15: Determine that the second acid hydrolysis pot transfer ball valve (421) and the third acid hydrolysis pot transfer ball valve (431) are in the closed state; Step 16: Open the transfer ball valve (411) of the first acid hydrolysis pot; Step 17: At the same time as the first acid hydrolysis pot transfer ball valve (411) is opened, the compressed air flow rate of the acid hydrolysis premix pot (300) reaches the set value; Step 18: Open the bottom valve (320) of the premixing pot and change the operating frequency of the acid hydrolysis premixing pot agitator (310) to 15Hz, and start the material transfer timing; Step 19: After the material transfer time reaches the set time, manually confirm that the material transfer is complete, and the premix material transfer process is completed; Step 20: Open the outlet valve (110) of the concentrated sulfuric acid metering tank; Step 21: When the weight of the secondary acid supply is equal to the set secondary acid ratio × the total weight of the acid supply, close the outlet valve (110) of the concentrated sulfuric acid metering tank; Step 22: Close the bottom valve (320) of the premixing pot and stop the agitator (310) of the acid hydrolysis premixing pot; close the transfer ball valve (411) of the first acid hydrolysis pot; Step 23: Program ends.

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