EA040131B1 - TESTING DEVICE AND METHOD FOR TESTING A ROTARY PRESSURE FILTER AND METHOD FOR FILTER DESIGN - Google Patents

Description

The field of technology to which the present invention relates

The invention relates to the field of a rotary pressure filter used for the manufacture and production of PTA (purified terephthalic acid, purified terephthalic acid), in particular to a testing device, a testing method and a method for designing a rotary pressure filter.

Background of the Invention

The rotary pressure filter is widely used in many applications, especially in the PTA related industry. Differences in material characteristics significantly affect the choice of pressure filter design and module. Traditionally, in order to test the characteristics of materials during the selection process of a rotary pressure filter design and module, a small-sized rotary pressure filter tester is required. The conventional testing apparatus is designed and manufactured exactly according to a large industrial rotary pressure filter and simply reduced in volume. The conventional testing device contains all the components of a large industrial rotary pressure filter, such as the drive system. Accordingly, the testing apparatus has a complicated structure and a high manufacturing cost. With such a conventional testing apparatus, the testing procedure is very complicated and expensive. In addition, due to the special characteristics of some materials, the washing and drying process may have to be repeated many times. However, since the small-sized rotary pressure filter test apparatus has a small volume, it is not possible to provide sufficient functional areas in the structure. Thus, it is not possible to perform the washing and drying processes many times to accurately mimic the requirements of materials or to obtain accurate design parameters for special materials.

Brief summary of the present invention

One object of the present invention is to provide a testing apparatus, a testing method and a method for designing a rotary pressure filter to overcome the shortcomings of the prior art small rotary pressure filter testing apparatus in which accurate slurry test parameters cannot be obtained.

To achieve the above object, the present invention provides a rotary pressure filter test apparatus, comprising: a pressure stabilization tank configured to be connected to a gas storage tank having a fixed pressure; a buffer tank for receiving sludge connected to the pressure stabilization tank through the first pipe; a filter frame configured to be part of a rotary pressure filter drum, said filter frame located below the buffer tank and connected to the buffer tank via a second tube; a reservoir for receiving liquid discharged from the filter frame, located under the filter frame, and under the filter frame and between the filter frame and the reservoir for receiving liquid is a valve; and an electronic scale located at the bottom of the liquid receiving tank for measuring the mass of liquid discharged into the liquid receiving tank.

In order to achieve the above object, the present invention further provides a method for testing a rotary pressure filter, comprising:

a first step of opening an inlet of the buffer tank, supplying sludge to the buffer tank, and moving the sludge to the filter frame;

the second stage of opening the gas valve in the gas inlet of the buffer tank, introducing gas at a pressure of 0.01-2.0 MPa into the buffer tank through the pressure stabilization tank, opening the valve at the bottom of the filter frame to perform filtration, measuring the filtration time, measuring the mass of the displaced filtrate for the same time by electronic balance and recording the measured mass, closing the valve at the bottom of the filter frame and the gas valve while displacing the filtrate in the filter frame to such an extent that the level of the filtrate is at the same level with the upper surface of the filter cake, venting gas from the filter frame, and then taking a sample of the filtrate to analyze the content of components and impurities contained in the filtrate;

the third stage of introducing the washing solution into the filter frame through the buffer tank to wash the sludge, introducing gas at a pressure of 0.01-2.0 MPa into the buffer tank through the pressure stabilization tank, and then into the filter frame through the buffer tank during the washing process, opening the valve at the bottom of the filter frame, measuring the weight of the displaced wash filtrate by means of an electronic balance until the weight of the displaced wash filtrate is equal to the weight of the injected wash solution, measuring the washing time, and taking a sample of the wash filtrate to analyze the content of components and impurities contained in the wash filtrate;

the fourth stage of introducing dry gas at a pressure of 0.01-2.0 MPa into the pressure stabilization tank, and then into the filter frame through the buffer tank, then opening the valve at the bottom of the filter frame, measuring the mass of the displaced solution using electronic scales, measuring the drying time, and then taking a sample of the dried filtrate to analyze the content of components and impurities contained in the dried filtrate; and a fifth step of opening the filter frame, measuring the thickness of the filter cake, and then taking a sample of the filter cake to analyze the moisture content of the filter cake, as well as the content of components and impurities contained in the filter cake.

In order to achieve the above object, the present invention further provides a rotary pressure filter, comprising:

a first step of opening an inlet of the buffer tank, supplying sludge to the buffer tank, and moving the sludge to the filter frame;

the second stage of opening the gas valve in the gas inlet of the buffer tank, introducing gas at a pressure of 0.01-2.0 MPa into the buffer tank through the pressure stabilization tank, opening the valve at the bottom of the filter frame to perform filtration, measuring the filtration time, measuring the mass of the displaced filtrate for the same time by electronic balance and recording the measured mass, closing the valve at the bottom of the filter frame and the gas valve while displacing the filtrate in the filter frame to such an extent that the level of the filtrate is at the same level with the upper surface of the filter cake, venting gas from the filter frame, and then taking a sample of the filtrate to analyze the content of components and impurities contained in the filtrate;

the third stage of introducing the washing solution into the filter frame through the buffer tank to wash the sludge, introducing gas at a pressure of 0.01-2.0 MPa into the buffer tank through the pressure stabilization tank, and then into the filter frame through the buffer tank during the washing process, opening the valve at the bottom of the filter frame, measuring the weight of the displaced wash filtrate by means of an electronic balance until the weight of the displaced wash filtrate is equal to the weight of the injected wash solution, measuring the washing time, and taking a sample of the wash filtrate to analyze the content of components and impurities contained in the wash filtrate;

the fourth stage of introducing dry gas at a pressure of 0.01-2.0 MPa into the pressure stabilization tank, and then into the filter frame through the buffer tank, then opening the valve at the bottom of the filter frame, measuring the mass of the displaced solution using electronic scales, measuring the drying time, and then taking a sample of the dried filtrate to analyze the content of components and impurities contained in the dried filtrate; and a fifth step of opening the filter frame, measuring the thickness of the filter cake, and then taking a sample of the filter cake to analyze the moisture content of the filter cake, as well as the content of components and impurities contained in the filter cake.

Brief description of the figures

The drawing shows a block diagram of a rotary pressure filter test apparatus according to the present invention.

Reference designation list:

- pressure stabilization tank;

- buffer tank;

- filter frame;

- a reservoir for receiving liquid;

- electronic balance;

- chronograph;

- gas storage tank.

Detailed disclosure of the present invention

The drawing shows a block diagram of a rotary pressure filter test apparatus according to the present invention. As shown in the drawing, the rotary pressure filter test apparatus according to the present invention may include a pressure stabilization tank 1; a buffer tank 2 connected to the pressure stabilization tank 1 via the first tube; a filter frame 3 located under the buffer tank 2 and connected to the buffer tank 2 via a second tube, with a valve under the filter frame 3; a reservoir 4 for receiving liquid, located under the filter frame 3; and electronic scales 5 located at the bottom of the tank 4 for receiving liquid.

In addition, the rotary pressure filter testing device according to the present invention may include a chronograph 6 for measuring the time to carry out the filtering, washing and drying processes.

In addition, the pressure stabilization tank 1 is connected to a gas storage tank 7 in which nitrogen gas, compressed air or other inert gases are stored. The gas storage tank 7 may be a fixed pressure gas source.

In addition, the present invention provides a method for testing a rotary pressure filter, comprising the steps of 1 opening the inlet of the buffer tank 2, supplying sludge to the buffer tank 2, and moving the sludge to the filter frame 3;

- 2 040131 stage 2 of opening the gas valve in the gas inlet of the buffer tank 2, introducing gas at a pressure of 0.01-2.0 MPa into the buffer tank 2 through the pressure stabilization tank 1, opening the valve at the bottom of the filter frame 3 to perform filtration, measuring time t filtration, measuring the mass m of the displaced filtrate at the same time, closing the valve at the bottom of the filter frame 3 and the gas valve while displacing the filtrate in the filter frame 3 to such an extent that the level of the filtrate is at the same level with the upper surface of the filter cake, gas removal from the filter frame 3, and then taking a sample of the filtrate to analyze the content of components and impurities contained in the filtrate;

stage 3 introducing the washing solution into the filter frame 3 through the buffer tank 2 for washing the filter housing, introducing gas at a pressure of 0.01-2.0 MPa into the buffer tank 2 through the pressure stabilization tank 1, and then into the filter frame 3 during the washing process , opening the valve at the bottom of the filter frame 3, measuring the mass of the displaced wash filtrate by means of the electronic balance 5 until the mass of the displaced wash filtrate is equal to the mass of the injected wash solution, measuring the washing time, and then taking a sample of the wash filtrate to analyze the content of the components and impurities contained in the washing filtrate;

stage 4 of introducing dry gas at a pressure of 0.01-2.0 MPa into the buffer tank 2 through the pressure stabilization tank 1, and then into the filter frame 3, opening the valve at the bottom of the filter frame 3, measuring the mass of the displaced liquid by means of electronic scales 5, measuring drying time, and then taking a sample of the dried filtrate to analyze the content of components and impurities contained in the dried filtrate; and step 5 of opening the filter frame 3, measuring the thickness of the filter cake, and then taking a sample of the filter cake to analyze the moisture content of the filter cake, as well as the content of components and impurities contained in the filter cake.

In this case, the sludge can be crude terephthalic acid sludge CTA (crude terephtalic acid), sludge purified terephthalic acid PTA (purified terephthalic acid), catalyst sludge, pulverized coal sludge or any other suspension in which solid and liquid can be freely separated by precipitation. . The gas may be nitrogen gas, compressed air or an inert gas.

In this case, if necessary, the filtration process in step 2 can be performed once or many times. If necessary, the washing process in stage 3 can be performed once or many times. If necessary, the drying process in step 4 can be performed once or multiple times. In addition, the order of the filtration process in step 2, the washing process in step 3, and the drying process in step 4 can be changed depending on the particular process. Preferably, the washing process in step 3 can be performed multiple times.

The filter frame 3 may have a round shape or a rectangular shape. The filter frame 3 can be filled with a filter holder wrapped with a filter cloth or other filter material. The pressure stabilization vessel 1 may be a pressure reducing valve or other pressure stabilization devices. On the other hand, the buffer tank 2 may be other supply buffer devices. On the other hand, the electronic scale 5 may be other weighing devices. On the other hand, the chronograph 6 may be other timing devices.

In addition, the present invention provides a method for designing a rotary pressure filter, including:

step 1 of opening an inlet of the buffer tank, supplying sludge to the buffer tank, and moving the sludge to the filter frame;

step 2 of opening the gas valve at the gas inlet of the buffer tank 2, introducing gas at a pressure of 0.01-2.0 MPa into the buffer tank 2 through the pressure stabilization tank 1, opening the valve at the bottom of the filter frame 3 to perform filtration, measuring the filtration time t, measuring the mass m of the displaced filtrate at the same time, closing the valve at the bottom of the filter frame 3 and the gas valve while displacing the filtrate in the filter frame 3 to such an extent that the level of the filtrate is at the same level with the upper surface of the filter cake, removing gas from the filter frame 3, and then taking a sample of the filtrate to analyze the content of components and impurities contained in the filtrate;

stage 3 introducing the washing solution into the filter frame 3 through the buffer tank 2 for washing the filter housing, introducing gas at a pressure of 0.01-2.0 MPa into the buffer tank 2 through the pressure stabilization tank 1, and then into the filter frame 3 during the washing process , opening the valve at the bottom of the filter frame 3, measuring the mass of the displaced wash filtrate by means of the electronic balance 5 until the mass of the displaced wash filtrate is equal to the mass of the injected wash solution, measuring the washing time, and then taking a sample of the wash filtrate to analyze the content of the components and impurities contained in the washing filtrate;

- 3 040131 stage 4 of introducing dry gas at a pressure of 0.01-2.0 MPa into the buffer tank 2 through the pressure stabilization tank, and then into the filter frame 3, opening the valve at the bottom of the filter frame 3, measuring the mass of displaced liquid by means of electronic scales 5 , measuring the drying time, and then taking a sample of the dried filtrate to analyze the content of components and impurities contained in the dried filtrate; and step 5 of opening the filter frame 3, measuring the thickness of the filter cake, and then taking a sample of the filter cake to analyze the moisture content of the filter cake, as well as the content of components and impurities contained in the filter cake.

Examples

1) Opened the inlet of buffer tank 2 while the other valves were closed. Then, 11.26 kg of STA slurry was introduced into the buffer tank 2, and then transferred to the filter frame 3.

2) The gas valve at the gas inlet of the buffer tank 2 was opened so that nitrogen gas could be introduced into the buffer tank 2 through the pressure stabilization tank 1 and then into the filter frame 3 at a current pressure of 0.5 MPa. To carry out the filtration, the valve at the bottom of the filter frame 3 was opened. The time t of the filtration process was measured as 33.6 s. The mass m of the displaced filtrate was measured as 4.63 kg. When displacing the filtrate in the filter frame 3 to such an extent that the level of the filtrate was at the same level as the upper surface of the filter cake, the valve at the bottom of the filter frame 3 and the gas valve for nitrogen gas were closed. Then, nitrogen gas was removed from the filter frame 3. Then samples of the filtrate were taken to analyze the content of acetic acid, as well as the content of impurities such as cobalt and manganese contained in the filtrate.

3) To wash the filter cake, 1.87 kg of washing solution was introduced into the filter frame 3 through the buffer tank 2, which was previously obtained by mixing acetic acid with water at an acetic acid concentration of 45%, 23%, 11% and 0%, respectively. During the washing process, nitrogen gas can be introduced into the buffer tank 2 through the pressure stabilization tank 1 and then into the filter frame 3 at a current pressure of 0.5 MPa. A valve at the bottom of the filter frame 3 was opened. During the washing process, the mass of the displaced washing solution was measured by means of an electronic balance 5 until the mass of the displaced washing filtrate was equal to the mass of the injected washing solution. The time of the washing process was measured. The washing process was carried out 4 times in total. In each of the four washing processes, the mass of displaced filtrate was the same, i.e. 1.87 kg. Wash times were 7.5 s, 6.3 s, 5.4 s and 4.8 s, respectively. To analyze the content of acetic acid, as well as the content of impurities such as cobalt and manganese contained in the washing filtrate, samples of the washing filtrate displaced in each of the four washing processes were taken.

4) Dry gas was introduced into the buffer tank 2 through the pressure stabilization tank 1 and then into the filter frame 3 at a current pressure of 0.5 MPa. Then, the valve at the bottom of the filter frame 3 was opened. The mass of the displaced liquid was measured as 2.1 kg by means of an electronic balance 5. The drying process time was measured as 11 seconds. To analyze the content of acetic acid, as well as the content of impurities such as cobalt and manganese contained in the dried filtrate, samples of the dried filtrate were taken.

5) The filter frame 3 was opened. The thickness of the filter cake was measured as 150 mm. In addition, samples of the filter cake were taken to analyze the moisture content of the filter cake as 15%, as well as to analyze the content of acetic acid, as well as the content of impurities such as cobalt and manganese contained in the filter cake.

Compared with the prior art, the present invention has the following advantages.

1) The present invention features a short testing process and a simple structure by adopting a simple testing method. The main component in the rotary pressure filter test apparatus according to the present invention is the filter frame, which may be a small part on the rotary pressure filter drum. Therefore, a simple structure and a low manufacturing cost can be obtained. On the other hand, the main component in the conventional testing apparatus is the rotary pressure filter testing apparatus, which is designed and manufactured exactly according to the large industrial rotary pressure filter, simply with reduced volume, and which contains all the components of the large industrial rotary pressure filter, such as the drive system. , resulting in a complex design and high manufacturing cost.

2) The present invention is able to fully simulate all the processes actually performed by the equipment according to the characteristics of the materials, such as the filtration process, the washing processes of various times, and the drying processes of various times, and provide reliable design parameters such as filtering capacity, results washing and drying results. When using the rotary pressure filter test apparatus according to the present invention for testing, all processes are independent and

- 4 040131 jerky and do not affect each other. In addition, test results of all processes can be analyzed and evaluated independently. Therefore, the results obtained can be accurate and reliable. On the other hand, the traditional rotary pressure filter test apparatus has certain limitations during testing. That is, the conventional testing apparatus operates continuously as an industrial machine, so that the test results of each process cannot be obtained directly. In addition, all processes are performed sequentially and they are related to each other. Consequently, processes can influence each other, making it impossible to obtain accurate and reliable results.

3) The present invention can simplify the complex testing process. That is, the rotary pressure filter test apparatus of the present invention can chain a series of simple blocks in order to fully and realistically simulate one or more running workflows in a complex device, and can obtain accurate and reliable results.

4) The present invention can fully comply with industrial design requirements, and can be applied to testing rotary pressure filters for PTA, CTA or other materials.

5) The present invention is capable of testing material parameters, i.e. Measure leachate and filter cake analysis parameters through filtration, washing and drying steps such as acetic acid content and impurities such as cobalt and manganese contained in CTA materials. In addition, material testing according to the present invention can be used to select and design a module during the manufacture of rotary pressure filters.

Of course, the invention may have other embodiments. Those skilled in the art may make various appropriate changes and modifications to the invention without departing from the spirit and spirit of the invention, but such changes and modifications are to be included within the protected scope of the appended claims.

Claims (10)

CLAIM 1. Rotary pressure filter testing device, comprising a pressure stabilization tank configured to be connected to a gas storage tank having a fixed pressure; a buffer tank for receiving sludge connected to the pressure stabilization tank through the first pipe; a filter frame configured to be part of a rotary pressure filter drum, said filter frame located below the buffer tank and connected to the buffer tank via a second tube; a reservoir for receiving liquid discharged from the filter frame, located under the filter frame, and under the filter frame and between the filter frame and the reservoir for receiving liquid is a valve; and an electronic scale located at the bottom of the liquid receiving tank for measuring the mass of liquid discharged into the liquid receiving tank. 2. The rotary pressure filter testing device according to claim 1, further comprising a chronograph for measuring time. 3. The rotary pressure filter test apparatus according to claim 1 or 2, wherein the pressure stabilization tank is connected to the gas storage tank. 4. Method for testing a rotary pressure filter by using a testing device according to any one of paragraphs. 1-3, comprising the first step of opening the inlet of the buffer tank, feeding the sludge into the buffer tank, and moving the sludge into the filter frame; the second stage of opening the gas valve in the gas inlet of the buffer tank, introducing gas at a pressure of 0.01-2.0 MPa into the buffer tank through the pressure stabilization tank, opening the valve at the bottom of the filter frame to perform filtration, measuring the filtration time, measuring the mass of displaced filtrate at the same time by electronic balance and recording the measured mass, closing the valve at the bottom of the filter frame and the gas valve while displacing the filtrate in the filter frame to such an extent that the level of the filtrate is at the same level with the upper surface of the filter cake, venting gas from the filter frame , and then taking a sample of the filtrate to analyze the content of components and impurities contained in the filtrate; the third stage of introducing the washing solution into the filter frame through the buffer tank to wash the sludge, introducing gas at a pressure of 0.01-2.0 MPa into the buffer tank through the pressure stabilization tank, and then into the filter frame through the buffer tank during the washing process, opening the valve at the bottom of the filter frame, measuring the mass of the displaced wash filtrate by means of an electronic balance until the mass of the displaced wash filtrate is equal to the mass of the injected wash solution, measuring the washing time and taking a sample of the wash filtrate to analyze the content of components and impurities contained in the washing filtrate; the fourth stage of introducing dry gas at a pressure of 0.01-2.0 MPa into the pressure stabilization tank, and then into the filter frame through the buffer tank, then opening the valve at the bottom of the filter frame, measuring the mass of the displaced solution using electronic scales, measuring the drying time, and then taking a sample of the dried filtrate to analyze the content of components and impurities contained in the dried filtrate; and a fifth step of opening the filter frame, measuring the thickness of the filter cake, and then taking a sample of the filter cake to analyze the moisture content of the filter cake, as well as the content of components and impurities contained in the filter cake. 5. The test method according to claim 4, wherein the slurry is a suspension in which solid and liquid can be freely separated by settling. 6. The test method according to claim 4 or 5, wherein the sludge is crude terephthalic acid sludge, purified terephthalic acid sludge, catalyst sludge, or pulverized coal sludge. 7. Testing method according to any one of paragraphs. 4-6, wherein the gas is nitrogen gas, compressed air, or an inert gas. 8. Testing method according to any one of paragraphs. 4-7, in which the filtration process in the second stage is performed once or many times; the washing process in the third stage is performed once or many times; the fourth-stage drying process is performed once or many times, and the order of the second-stage filtration process, the third-stage washing process, and the fourth-stage drying process can be changed. 9. The test method according to any one of claims 4 to 8, wherein the pressure stabilization reservoir is a pressure reducing valve. 10. The method of designing a rotary pressure filter, including the application of the testing method according to any one of paragraphs. 4-9 to test the independent processes to be carried out by the designed rotary pressure filter to obtain design parameters for the independent processes; said design parameters include filtering capacity, washing results and/or drying results, and/or for testing the sludge to be filtered by the rotary pressure filter to obtain the parameters of the sludge, and selecting the module of the rotary pressure filter to be designed using the obtained parameters.