Testing device and method for evaluating chlorine resistance of material

Abstract

The invention provides a test device and method for evaluating chlorine resistance of a material. The test device comprises a water treatment unit; a chlorine dioxide generating unit; the storage tank is used for mixing the purified water and the chlorine dioxide therein to form a test solution; the test system comprises a water tank and a test unit, the test unit comprises at least one sample rack and a test device, the sample rack is used for fixing a test sample, and the test device is used for monitoring the performance of the test sample; the circulating system comprises a circulating pipeline and a circulating pump, the circulating pipeline is used for communicating the storage tank with the water tank to form a circulating path, and the circulating pump is used for enabling the test solution to circularly flow in the circulating path; and the wastewater treatment unit is communicated with the circulating pipeline and is used for reducing the test solution separated from the circulating pipeline and discharging the test solution out of the device. The test device is provided with the circulating system, so that various parameters of the test solution can be kept stable, and meanwhile, the operability, the safety and the environmental protection are obviously improved.

Description

Technical Field

[0001] The invention relates to the field of material chlorine resistance evaluation, and in particular to a test device and method for evaluating the chlorine resistance of a material. Background Art

[0002] In order to ensure water safety, an appropriate amount of disinfectant needs to be added to drinking tap water, swimming pools, public baths, etc., and a certain amount of residual is maintained. Common disinfectants include chlorine (including liquid chlorine, sodium hypochlorite and calcium hypochlorite, etc.), chloramines and chlorine dioxide, etc. At present, chlorine disinfectants are the most widely used. Although existing studies have shown that free chlorine at the limit concentration level will not have harmful effects on the human body, chlorine disinfection will produce a large number of by-products, some of which have pungent odors or are harmful to the human body. Therefore, it is necessary to strictly control the residual amount of free chlorine in the water leaving the factory. In comparison, chloramine and chlorine dioxide disinfection produce fewer by-products, but chloramine has a weaker disinfection ability and is often used as a second disinfectant. Chlorine dioxide has a strong broad-spectrum bactericidal ability in a wider pH range, so it is recommended to use chlorine dioxide for disinfection in many newly built water treatment devices.

[0003] Polyolefin pipe systems, such as polyethylene, cross-linked polyethylene and polypropylene pipes, are often used to transport drinking water and supply hot water. It has been reported that chlorine-containing disinfectants in water have an adverse effect on the service life of pipes. The reason is that chlorine-containing disinfectants are highly oxidizing and will continuously corrode the pipes, causing the inner surface of the pipes to gradually oxidize, chlorinate and degrade, forming a brittle layer and producing many small cracks. Eventually, the cracks extend outward along the pipe wall, causing the pipes to be damaged. In order to evaluate and compare the chlorine oxidation resistance of pipes, ASTM F2023 and ASTM F2263 can be used for experiments, and the material grades can be classified according to the rules of ASTM F876 or ASTM D3350. However, the test medium of the existing standard method is chlorine / hypochlorous acid, and there is no regulation for other disinfectant media. In particular, the effect of the more environmentally friendly chlorine dioxide disinfectant on the long-term performance of polyolefin materials is not easy to study and evaluate. Compared with free chlorine, chlorine dioxide has stronger disinfection ability and oxidation effect, and is more easily reactive with commonly used antioxidants such as hindered phenols, and has a greater impact on the performance of materials in pipelines. However, chlorine dioxide is sensitive to light and temperature, making it difficult to carry out evaluation experiments, and there is also a lack of dedicated testing equipment.

[0004] Based on this background, the present invention has developed a test device and method for evaluating the chlorine resistance of materials. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present invention provides a test device and method for evaluating the chlorine resistance of a material. The test device is provided with a circulation system, which can ensure that various parameters of a test solution remain stable, and at the same time, has obvious improvements in operability, safety and environmental protection, thereby solving the problem that a conventional laboratory solution immersion method cannot control the volatilization of a chlorine dioxide solution and has an unstable concentration.

[0006] In order to achieve the above object, the first aspect of the present invention provides a test device for evaluating the chlorine resistance of a material, the test device comprising:

[0007] a water treatment unit for treating the water supply to provide purified water;

[0008] A chlorine dioxide generating unit, used for providing chlorine dioxide;

[0009] A storage tank, used for mixing the purified water and the chlorine dioxide therein to form a test solution;

[0010] A test system, comprising a water tank and a test unit, wherein the test unit comprises at least one sample rack and a test device, wherein the sample rack is used to fix a test sample, and the test device is used to monitor changes in the performance of the test sample;

[0011] A circulation system, comprising a circulation pipeline and a circulation pump, wherein the circulation pipeline is used to connect the storage tank with the water tank to form a circulation passage, and the circulation pump is used to circulate the test solution in the circulation passage;

[0012] The wastewater treatment unit is connected to the circulation pipeline and is used for reducing and treating the test solution separated from the circulation pipeline and discharging it from the device.

[0013] A second aspect of the present invention provides a test method performed in the above test device, the test method comprising the following steps:

[0014] treating a water supply to obtain purified water, and mixing the purified water with chlorine dioxide to form a test solution;

[0015] Placing the test sample in the device, allowing the test solution to soak and circulate over the surface of the test sample;

[0016] performing a reduction treatment on the discharged test solution;

[0017] The changes in the properties of the test specimens soaked in the test solutions are monitored.

[0018] The effects of the present invention are:

[0019] (1) The test device for evaluating the chlorine resistance of materials proposed in the present invention is provided with a circulation system. By controlling the flow rate of adding and discharging the solution, the test solution can be continuously replaced and updated to ensure that various parameters of the test solution remain stable, reduce the impact of disinfection by-products on the test, and at the same time have obvious improvements in operability, safety and environmental protection.

[0020] (2) The test method for evaluating the chlorine resistance of materials proposed in the present invention solves the problem that the conventional laboratory solution immersion method cannot control the volatilization of chlorine dioxide solution and the concentration is unstable.

[0021] (3) The test device for evaluating the chlorine resistance of a material proposed in the present invention is a multifunctional testing machine, and is provided with a tension sensor and a displacement sensor, so as to facilitate testing the creep performance of a specimen, or testing the crack propagation of a test piece or a specimen, or testing the behavior of a pipe section under a ring tensile load.

[0022] (4) The test device for evaluating the chlorine resistance of materials proposed in the present invention is provided with a pH sensor, a temperature sensor, a chlorine dioxide sensor and a redox potential sensor, which can monitor the pH value, temperature, chlorine dioxide concentration, and redox potential value of the solution in a storage tank, a water tank or a circulation system, so that the test is accurate and controllable.

[0023] (5) The test device for evaluating the chlorine resistance of materials proposed in the present invention is a closed device, which avoids the influence of the external environment on the test solution and ensures the accuracy of the entire test.

[0024] (6) The test device for evaluating the chlorine resistance of a material proposed in the present invention is also provided with a controller for shutting down the device when the chlorine dioxide gas alarm sounds, thereby ensuring the safety and reliability of the test device.

[0025] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The above and other objects, features and advantages of the present invention will become more apparent through a more detailed description of exemplary embodiments of the present invention in conjunction with the accompanying drawings, wherein like reference numerals generally represent like components throughout the exemplary embodiments of the present invention.

[0027] Figure 1 The present invention is a schematic flow chart of a test device for evaluating the chlorine resistance of a material.

[0028] Figure 2A This is a front view schematic diagram of the overall structure of the test device for evaluating the chlorine resistance of materials proposed by the present invention.

[0029] Figure 2BThis is a schematic top view of the overall structure of the test device for evaluating the chlorine resistance of materials proposed in the present invention.

[0030] Figure 3A A schematic diagram of the overall structure of a ring tensile fixture of a test device for evaluating the chlorine resistance of a material proposed in the present invention.

[0031] Figure 3B A schematic diagram of the specific structure of a ring tensile fixture of a test device for evaluating the chlorine resistance of a material proposed in the present invention.

[0032] Description of reference numerals:

[0033] 1-water treatment unit, 2-chlorine dioxide generation unit, 3-storage tank, 4-test system, 5-circulation system, 6-wastewater treatment unit;

[0034] 101-filtering device, 102-softening device, 103-chlorine dioxide generating device, 104-circulating pipeline, 105-circulating pump, 106-water tank, 107-testing unit, 108-ring tensile fixture;

[0035] 201-upper clamp, 202-lower clamp, 203-stretching guide rod, 204-stretching rod;

[0036] 301-upper clamp, 302-upper sliding piece, 303-lower clamp, 304-lower fixing piece. DETAILED DESCRIPTION

[0037] The preferred embodiments of the present invention will be described in more detail below. Although the preferred embodiments of the present invention are described below, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein.

[0038] In the present disclosure, unless otherwise stated, directional words such as "upper and lower" generally refer to the upper and lower parts of the device in normal use, for example, with reference to the drawing direction of Figure 2a, and "inside and outside" refer to the outline of the device. In addition, the terms "first, second, third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, features defined as "first, second, third" may explicitly or implicitly include one or more of the features. In the description of the present disclosure, "multiple" means two or more, unless otherwise clearly and specifically defined.

[0039] The present invention provides a test device for evaluating the chlorine resistance of a material, such as Figure 1 , Figure 2A , Figure 2B As shown, the test device includes:

[0040] A water treatment unit 1 for treating the supplied water to provide purified water;

[0041] A chlorine dioxide generating unit 2, for providing chlorine dioxide;

[0042] A storage tank 3, used for mixing purified water and chlorine dioxide therein to form a test solution;

[0043] The test system 4 includes a water tank 106 and a test unit 107, wherein the test unit 107 includes at least one sample rack and a test device, wherein the sample rack is used to fix the test sample, and the test device is used to monitor the change of the performance of the test sample;

[0044] The circulation system 5 includes a circulation pipeline 104 and a circulation pump 105. The circulation pipeline 104 is used to connect the storage tank 3 with the water tank 106 to form a circulation path. The circulation pump 105 is used to circulate the test solution in the circulation path.

[0045] The wastewater treatment unit 6 is connected to the circulation pipeline 104 and is used for reducing and treating the test solution separated from the circulation pipeline 104 and discharging it out of the device.

[0046] In the present invention, the test device is provided with a circulation system 5, which can continuously replace and update the test solution by controlling the flow rate of adding and discharging the solution, ensuring that various parameters of the test solution remain stable, while significantly improving operability, safety and environmental protection.

[0047] According to the present invention, the water treatment unit 1 comprises a filtration device 101, a softening device 102 and an optional reverse osmosis device connected in sequence;

[0048] The filtering device 101 is used to filter foreign particles in the water supply, the softening device 102 is used to remove foreign ions that form scale in the water supply, and the reverse osmosis device is used to remove all foreign ions in the water supply.

[0049] Preferably, the chlorine dioxide generating unit 2 comprises a chlorine dioxide generating device 103 and a chlorine dioxide regulating device, and the chlorine dioxide regulating device is used to adjust the amount of chlorine dioxide generated and / or the amount of addition according to the concentration of chlorine dioxide in the storage tank 3 and / or the test system 4;

[0050] The chlorine dioxide generating device 103 is selected from a one-component generating device or a two-component generating device. The one-component generating device is preferably a chlorine dioxide effervescent tablet adding device, and the two-component generating device is preferably a generator that generates chlorine dioxide by the reaction of chlorite and an activator.

[0051] According to a preferred embodiment of the present invention, a liquid level meter is provided in the storage tank 3 for determining the liquid level inside the storage tank 3 and adjusting the amount of purified water and chlorine dioxide solution added accordingly.

[0052] According to the present invention, the test sample is a test piece, a specimen or a pipe section of a polyolefin material;

[0053] Each sample holder is provided with an adaptor fixture, and the adaptor fixture is preferably at least one of an immersion fixture, a stretching fixture, and a ring stretching fixture 108;

[0054] The test device is a multifunctional testing machine equipped with a tension sensor and a displacement sensor, which is used to test the creep performance of the specimen, or to test the crack propagation of the test piece or specimen, or to test the behavior of the pipe section under the condition of ring tensile load.

[0055] Preferably, the circulation system 5 further comprises a circulation flow meter, which is used to monitor the flow rate of the circulating test solution.

[0056] According to the present invention, the storage tank 3 and the water tank 106 are each independently provided with a heater, and the heater is used to control the temperature of the test solution.

[0057] Preferably, the materials of the circulation pipeline 104, the circulation pump 105, the inner wall of the storage tank 3 and the water tank 106, and the materials of at least one sample holder and the adapter fixture are independently selected from any one of stainless steel and high temperature and corrosion resistant engineering plastics;

[0058] The stainless steel is preferably 316 stainless steel;

[0059] The high temperature resistant and corrosion resistant engineering plastic is preferably polyvinylidene fluoride.

[0060] According to a preferred embodiment of the present invention, a temperature sensor, a pH sensor, a chlorine dioxide concentration sensor and a redox potential sensor are provided on the storage tank 3 or the water tank 106 or the circulation pipeline 104. The temperature sensor, the pH sensor, the chlorine dioxide concentration sensor and the redox potential sensor are used to detect the temperature, the pH value, the chlorine dioxide concentration and the redox potential value of the test solution, respectively, so that the test experiment is accurate and controllable.

[0061] Preferably, the test device is a closed device and is provided with a chlorine dioxide gas alarm;

[0062] In the present invention, the test device is also provided with a controller for shutting down the chlorine dioxide generator 103 and the circulation pump 105 when the chlorine dioxide gas alarm sounds, thereby ensuring the safety and reliability of the test device.

[0063] According to the present invention, the wastewater treatment device further comprises a valve, a flow meter and a flow pump, wherein the valve is used to control the discharge amount of the test solution entering the wastewater treatment unit 6, the flow meter is used to monitor the discharge amount, and the flow pump is used to add the reducing agent according to the stoichiometric ratio.

[0064] Preferably, the water treatment unit 1, the chlorine dioxide generating unit 2, the storage tank 3 and the wastewater treatment device are integrated in one space as a mixed liquid system;

[0065] like Figure 3A , 3B As shown, the ring stretching fixture 108 includes an upper fixture 201, a lower fixture 202, a pair of stretching guide rods 203 and a stretching rod 204;

[0066] The upper fixture 201 includes an upper clamp 301 and an upper slide 302. The upper clamp 301 is vertically connected to the middle of the upper slide 302 to form a T-shape. The upper clamp 301 is provided with a stretching screw hole and a first sample screw hole at both ends. The upper slide 302 is in a rectangular shape and is provided with a pair of sliding through holes at both ends. The pair of sliding through holes are respectively sleeved on a pair of stretching guide rods 203 for the upper slide 302 to slide along the pair of stretching guide rods 203.

[0067] The lower clamp 202 includes a lower clamp 303 and a lower fixing member 304. The lower clamp 303 is vertically connected to the middle of the lower fixing member 304 to form a T-shape. A second sample screw hole is provided at one end of the lower clamp 303. The lower fixing member 304 is in a rectangular parallelepiped shape and a pair of fixing screw holes are provided at both ends thereof. The pair of fixing screw holes are respectively connected to one end of a pair of stretching guide rods 203, so as to fix the pair of stretching guide rods 203 on the lower fixing member 304.

[0068] One end of the test sample is connected to the upper clamp 301 through the first sample screw hole, and the other end is connected to the lower clamp 303 through the second sample screw hole;

[0069] One end of the stretching rod 204 is connected to the upper clamp 301 through a stretching screw hole, and the other end is connected to the testing device;

[0070] The axes of the upper clamp 301, the lower clamp 303, each stretching guide rod 203, and the stretching rod 204 are parallel to each other;

[0071] The upper clamping head 301 and the lower clamping head 303 may have the same or different shapes and sizes;

[0072] The upper sliding member 302 and the lower fixing member 304 may have the same or different shapes and sizes;

[0073] The test sample is a polyolefin pipe, and the test device is a ring tensile creep test device with multiple independent stations.

[0074] The test device in the present invention is a closed device, which avoids the influence of the external environment on the test solution and ensures the accuracy of the entire test.

[0075] The present invention also provides a test method performed in the above test device, the test method comprising the following steps:

[0076] Treating the water supply to obtain purified water, and mixing the purified water with chlorine dioxide to form a test solution;

[0077] Placing the test sample in the water tank 106, allowing the test solution to soak and circulate over the surface of the test sample;

[0078] Performing reduction treatment on the discharged test solution;

[0079] The changes in properties of the test specimens soaked in the test solution are monitored.

[0080] According to the present invention, treating the water supply comprises filtering, softening and optionally reverse osmosis of the water supply in sequence;

[0081] Filtration is used to filter out impurity particles in the water supply, softening is used to remove scale-forming impurity ions in the water supply, and reverse osmosis is used to remove all impurity ions in the water supply.

[0082] The method according to the present invention further comprises at least one of the following steps:

[0083] i) regulating the amount of chlorine dioxide generated, and / or adjusting the amount of chlorine dioxide added;

[0084] ii) monitoring the temperature, flow rate, pH value, chlorine dioxide concentration and redox potential of the circulating test solution;

[0085] iii) monitoring the state of the reduction treatment and the discharge amount of the test solution after the reduction treatment;

[0086] iv) monitoring the concentration of chlorine dioxide gas inside and / or outside the device.

[0087] Preferably, the properties of the test specimen include the creep properties of a specimen, or the crack growth resistance of a test piece or specimen, or the behavior of a pipe section under annular tension loading.

[0088] According to the present invention, the concentration of chlorine dioxide in the test solution is 1 to 5 ppm;

[0089] The temperature of the circulating test solution is 25°C to 70°C;

[0090] The reducing agent used in the reduction treatment is sodium thiosulfate, sodium sulfite or sodium bisulfite;

[0091] The circulating flow rate of the test solution is 1 to 5 m 3 / h, the replacement rate is 0.1~2m 3 / sky.

[0092] In the present invention, the test method solves the problem that the conventional laboratory solution immersion method cannot control the volatilization of the chlorine dioxide solution and the concentration is unstable.

[0093] The present invention will be described in more detail below by way of examples.

[0094] Example 1

[0095] This embodiment provides a ring tensile creep test device for evaluating the resistance of polyolefin pipes to chlorine dioxide solutions. Figure 1 , Figure 2A and Figure 2B As shown, the test device includes:

[0096] A water treatment unit 1 for treating the supplied water to provide purified water;

[0097] A chlorine dioxide generating unit 2, for providing chlorine dioxide;

[0098] A storage tank 3, used for mixing purified water and chlorine dioxide therein to form a test solution;

[0099] A test system 4, comprising a water tank 106 and a test unit 107 disposed in the water tank 106, the test unit 107 comprising ten ring tensile fixtures 108 and a test device, the ten ring tensile fixtures 108 being used to fix the test sample, and the test device being used to monitor changes in the performance of the test sample;

[0100] The circulation system 5 includes a circulation pipeline 104 and a circulation pump 105. The circulation pipeline 104 is used to connect the storage tank 3 with the water tank 106 to form a circulation path. The circulation pump 105 is used to circulate the test solution in the circulation path.

[0101] The wastewater treatment unit 6 is connected to the circulation pipeline 104 and is used for reducing and treating the test solution separated from the circulation pipeline 104 and discharging it out of the device;

[0102] The water treatment unit 1 comprises a filtering device 101 and a softening device 102 which are connected in sequence;

[0103] The filtering device 101 is used to filter the impurity particles in the water supply, and the softening device 102 is used to remove the impurity ions that form scale in the water supply;

[0104] The chlorine dioxide generating unit 2 includes a chlorine dioxide generating device 103 and a chlorine dioxide regulating device, and the chlorine dioxide regulating device is used to adjust the amount of chlorine dioxide generated and added according to the concentration of chlorine dioxide in the storage tank 3 and the test system 4;

[0105] The chlorine dioxide generating device 103 is a device that generates chlorine dioxide by reacting a binary reagent;

[0106] A liquid level meter (not shown) is provided in the storage tank 3 to determine the liquid level inside the storage tank 3 and adjust the amount of purified water and chlorine dioxide solution added accordingly;

[0107] The test sample is a pipe section made of polyolefin material;

[0108] The test device is a multifunctional testing machine equipped with a tension sensor and a displacement sensor, which is used to test the behavior of the pipe section under the tensile load of the ring;

[0109] The circulation system 5 further includes a circulation flow meter (not shown), which is used to monitor the flow rate of the circulating test solution;

[0110] The storage tank 3 and the water tank 106 are each independently provided with a heater (not shown), and the heater is used to control the temperature of the test solution;

[0111] The materials of the circulation pipeline 104, the circulation pump 105, the inner wall of the storage tank 3 and the water tank 106, and the ring stretching fixture 108 are all 316 stainless steel;

[0112] The water tank 106 is provided with a temperature sensor (not shown), a pH sensor (not shown), a chlorine dioxide concentration sensor (not shown) and an oxidation-reduction potential sensor (not shown), and the temperature sensor (not shown), the pH sensor (not shown), the chlorine dioxide concentration sensor (not shown) and the oxidation-reduction potential sensor (not shown) are used to detect the temperature, pH value, chlorine dioxide concentration and oxidation-reduction potential value of the test solution, respectively;

[0113] The test device is a closed device and is equipped with a chlorine dioxide gas alarm (not shown);

[0114] The test device also includes a controller (not shown) for shutting down the chlorine dioxide generator 103 and the circulation pump 105 when the chlorine dioxide gas alarm sounds;

[0115] The wastewater treatment device further includes a valve (not shown), a flow meter (not shown) and a flow pump (not shown), wherein the valve (not shown) is used to control the discharge amount of the test solution entering the wastewater treatment unit 6, the flow meter (not shown) is used to monitor the discharge amount, and the flow pump (not shown) is used to add the reducing agent according to the stoichiometric ratio;

[0116] The water treatment unit 1, the chlorine dioxide generating unit 2, the storage tank 3 and the wastewater treatment device are integrated in one space as a mixed liquid system;

[0117] like Figure 3A , 3B As shown, the ring stretching fixture 108 includes an upper fixture 201, a lower fixture 202, a pair of stretching guide rods 203 and a stretching rod 204;

[0118] The upper fixture 201 includes an upper clamp 301 and an upper slide 302. The upper clamp 301 is vertically connected to the middle of the upper slide 302 to form a T-shape. The upper clamp 301 is provided with a stretching screw hole and a first sample screw hole at both ends. The upper slide 302 is in a rectangular shape and is provided with a pair of sliding through holes at both ends. The pair of sliding through holes are respectively sleeved on a pair of stretching guide rods 203 for the upper slide 302 to slide along the pair of stretching guide rods 203.

[0119] The lower clamp 202 includes a lower clamp 303 and a lower fixing member 304. The lower clamp 303 is vertically connected to the middle of the lower fixing member 304 to form a T-shape. A second sample screw hole is provided at one end of the lower clamp 303. The lower fixing member 304 is in a rectangular parallelepiped shape and a pair of fixing screw holes are provided at both ends thereof. The pair of fixing screw holes are respectively connected to one end of a pair of stretching guide rods 203, so as to fix the pair of stretching guide rods 203 on the lower fixing member 304.

[0120] One end of the test sample is connected to the upper clamp 301 through the first sample screw hole, and the other end is connected to the lower clamp 303 through the second sample screw hole;

[0121] One end of the stretching rod 204 is connected to the upper clamp 301 through a stretching screw hole, and the other end is connected to the testing device;

[0122] The axes of the upper clamp 301, the lower clamp 303, each stretching guide rod 203, and the stretching rod 204 are parallel to each other;

[0123] The upper clamping head 301 and the lower clamping head 303 have the same shape and size;

[0124] The upper sliding member 302 and the lower fixing member 304 have the same shape and size;

[0125] The testing device is a ring tensile creep testing device with multiple independent working stations.

[0126] This embodiment provides a test method performed in the above test device, and the test method comprises the following steps:

[0127] The water supply is filtered and softened in sequence to obtain purified water, the amount of chlorine dioxide added is adjusted, and the purified water and chlorine dioxide are mixed to form a test solution;

[0128] Ten polyolefin pipes are respectively fixed on ten ring stretching fixtures 108, and then placed in a water tank 106, so that a test solution with a chlorine dioxide concentration of 3 ppm and a temperature of 40° C. is soaked and circulated through the surface of each polyolefin pipe, and the temperature, flow rate, pH value and chlorine dioxide concentration of the circulating test solution are monitored at the same time;

[0129] The ring tensile creep performance of polyolefin pipes against chlorine dioxide solution was monitored using a test device;

[0130] The flow rate of the test solution circulation is 2.5m 3 / h, replacement rate is about 1m 3 / day, and the discharged test solution is reduced with sodium thiosulfate, while the state of the reduction treatment is monitored and the discharge amount of the test solution after the reduction treatment is monitored.

[0131] Embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A test device for evaluating the chlorine resistance of a material, characterized in that: The test device comprises: a water treatment unit for treating the water supply to provide purified water; A chlorine dioxide generating unit, used for providing chlorine dioxide; A storage tank, used for mixing the purified water and the chlorine dioxide therein to form a test solution; A test system, comprising a water tank and a test unit, wherein the test unit comprises at least one sample rack and a test device, wherein the sample rack is used to fix a test sample, and the test device is used to monitor changes in the performance of the test sample; A circulation system, comprising a circulation pipeline and a circulation pump, wherein the circulation pipeline is used to connect the storage tank with the water tank to form a circulation passage, and the circulation pump is used to circulate the test solution in the circulation passage; The wastewater treatment unit is connected to the circulation pipeline and is used for reducing and treating the test solution separated from the circulation pipeline and discharging it from the device.

2. The test device according to claim 1, characterized in that: The water treatment unit comprises a filtering device, a softening device and an optional reverse osmosis device connected in sequence; The filtering device is used to filter foreign particles in the water supply, the softening device is used to remove foreign ions that form scale in the water supply, and the reverse osmosis device is used to remove all foreign ions in the water supply.

3. The test device according to claim 1, characterized in that: The chlorine dioxide generating unit comprises a chlorine dioxide generating device and a chlorine dioxide regulating device, wherein the chlorine dioxide regulating device is used to adjust the amount of chlorine dioxide generated and / or added according to the concentration of chlorine dioxide in the storage tank and / or the test system; The chlorine dioxide generating device is selected from a one-component generating device or a two-component generating device. The one-component generating device is preferably a chlorine dioxide effervescent tablet adding device, and the two-component generating device is preferably a generator that generates chlorine dioxide by the reaction of chlorite and an activator.

4. The test device according to claim 1, characterized in that: A liquid level meter is provided in the storage tank for determining the liquid level inside the storage tank and adjusting the amount of the purified water and the chlorine dioxide solution added accordingly.

5. The test device according to claim 1, characterized in that: The test sample is a test piece, a specimen strip or a pipe section of a polyolefin material; Each sample holder is provided with an adaptor fixture, and the adaptor fixture is preferably at least one of an immersion fixture, a stretching fixture, and a ring stretching fixture; The testing device is preferably a multifunctional testing machine equipped with a tension sensor and a displacement sensor, which is used to test the creep performance of the specimen, or to test the crack propagation of the test piece or specimen, or to test the behavior of the pipe section under the ring tensile load.

6. The test device according to claim 1, characterized in that: The circulation system further comprises a circulation flow meter, which is used for monitoring the flow rate of the circulating test solution.

7. The test device according to claim 1, characterized in that: The storage tank and the water tank are each independently provided with a heater, and the heater is used to control the temperature of the test solution.

8. The test device according to claim 1, characterized in that: The materials of the inner wall of the circulation pipeline, the circulation pump, the storage tank and the water tank, and the materials of the at least one sample holder and the adapter fixture are independently selected from any one of stainless steel and high temperature and corrosion resistant engineering plastics; The stainless steel is preferably 316 stainless steel; The high temperature resistant and corrosion resistant engineering plastic is preferably polyvinylidene fluoride.

9. The test device according to claim 1, characterized in that: The storage tank or the water tank or the circulation pipeline is provided with a temperature sensor, a pH sensor, a chlorine dioxide concentration sensor and an oxidation-reduction potential sensor, and the temperature sensor, the pH sensor, the chlorine dioxide concentration sensor and the oxidation-reduction potential sensor are used to detect the temperature, pH value, chlorine dioxide concentration and oxidation-reduction potential value of the test solution, respectively.

10. The test device according to claim 1, characterized in that: The test device is a closed device and is provided with a chlorine dioxide gas alarm; The test device also includes a controller, which is used to shut down the chlorine dioxide generating device and the circulation pump when the chlorine dioxide gas alarm sounds.

11. The test device according to claim 1, characterized in that: The wastewater treatment device further comprises a valve, a flow meter and a flow pump, wherein the valve is used to control the discharge amount of the test solution entering the wastewater treatment unit, the flow meter is used to monitor the discharge amount, and the flow pump is used to add a reducing agent according to a stoichiometric ratio.

12. The test device according to claim 1, characterized in that: The water treatment unit, chlorine dioxide generation unit, storage tank and wastewater treatment device are integrated in one space as a mixed liquid system; The ring stretching fixture comprises an upper fixture, a lower fixture, a pair of stretching guide rods and a stretching rod; The upper fixture comprises an upper clamp and an upper sliding member, the upper clamp is vertically connected to the middle of the upper sliding member and forms a T-shape, a stretching screw hole and a first sample screw hole are respectively provided at both ends of the upper clamp, the upper sliding member is in a rectangular parallelepiped shape, and a pair of sliding through holes are respectively provided at both ends thereof, the pair of sliding through holes are respectively sleeved on the pair of stretching guide rods, and are used for the upper sliding member to slide along the pair of stretching guide rods; The lower fixture comprises a lower clamp and a lower fixing member, wherein the lower clamp is vertically connected to the middle of the lower fixing member to form a T-shape, a second sample screw hole is provided at one end of the lower clamp, and the lower fixing member is in a rectangular parallelepiped shape, and a pair of fixing screw holes are respectively provided at both ends thereof, and the pair of fixing screw holes are respectively connected to one end of the pair of stretching guide rods, and are used to fix the pair of stretching guide rods on the lower fixing member; One end of the test sample is connected to the upper clamp through the first sample screw hole, and the other end is connected to the lower clamp through the second sample screw hole; One end of the stretching rod is connected to the upper clamp through a stretching screw hole, and the other end is connected to the testing device; The axes of the upper chuck, the lower chuck, each stretching guide rod, and the stretching rod are parallel to each other; The upper clamping head and the lower clamping head have the same or different shapes and sizes; The upper sliding member and the lower fixing member have the same or different shapes and sizes; The test sample is a polyolefin pipe, and the test device is a ring tensile creep test device with multiple independent stations.

13. A test method for evaluating the chlorine resistance of a material, characterized in that: The test method comprises the following steps: treating a water supply to obtain purified water, and mixing the purified water with chlorine dioxide to form a test solution; Placing the test sample in the device, allowing the test solution to soak and circulate over the surface of the test sample; performing a reduction treatment on the discharged test solution; The changes in the properties of the test specimens soaked in the test solutions are monitored.

14. The test method according to claim 13, characterized in that The treatment of the water supply includes filtering, softening and optionally reverse osmosis of the water supply in sequence; The filtration is used to filter foreign particles in the water supply, the softening is used to remove foreign ions that form scale in the water supply, and the reverse osmosis is used to remove all foreign ions in the water supply.

15. The test method according to claim 13, characterized in that: The method further comprises at least one of the following steps: i) regulating the amount of chlorine dioxide generated, and / or adjusting the amount of chlorine dioxide added; ii) monitoring the temperature, flow rate, pH value, chlorine dioxide concentration and redox potential of the circulating test solution; iii) monitoring the state of the reduction treatment and the discharge amount of the test solution after the reduction treatment; iv) monitoring the concentration of chlorine dioxide gas inside and / or outside the device.

16. The test method according to claim 13, characterized in that: The properties of the test specimens include the creep properties of a specimen, or the crack growth resistance of a test piece or specimen, or the behavior of a pipe section under an annular tensile load.

17. The test method according to any one of claims 13 to 16, characterized in that: The chlorine dioxide concentration in the circulating test solution is 1 to 5 ppm; The temperature of the circulating test solution is 25°C to 70°C; The reducing agent used in the reduction treatment is sodium thiosulfate, sodium sulfite or sodium bisulfite; The test solution circulates at a flow rate of 1 to 5 m 3 / h, the discharge replacement rate is 0.1~2m 3 / sky.

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